Cirque du Monde en tant qu’intervention en santé

PubMed Central

Fournier, Cynthia; Drouin, Mélodie-Anne; Marcoux, Jérémie; Garel, Patricia; Bochud, Emmanuel; Théberge, Julie; Aubertin, Patrice; Favreau, Gil; Fleet, Richard

2014-01-01

Résumé Objectif Présenter le programme Cirque du Monde du Cirque du Soleil et son potentiel en tant qu’intervention en soins de santé de première ligne pour les médecins de famille. Sources des données Une revue de la littérature menée dans les bases de données PubMed, Cochrane Library, PsycINFO, La Presse, Eureka, Google Scholar et Érudit à l’aide des mots-clés circus, social circus, Cirque du Monde et Cirque du Soleil. Une initiative à Montréal nommée Espace Transition qui s’inspire directement de Cirque du Monde. Communication personnelle avec le conseiller principal en formation en cirque social du Cirque du Soleil. Sélection d’études Les 50 premiers articles ou sites Internet répertoriés pour chaque mot-clé dans chacune des bases de données ciblées ont été révisés sur la base des titres et des résumés, s’il s’agissait d’un article, ou sur la base du titre et du contenu de la page, s’il s’agissait d’une page Internet. Ensuite, les articles et les sites Internet qui étudiaient un aspect du cirque social ou qui présentaient une intervention impliquant le cirque étaient retenus pour une révision. Aucune contrainte d’année de publication n’a été appliquée étant donné qu’on cherchait une littérature générale sur le cirque social. Synthèse Aucun article n’a été trouvé sur le cirque social en tant qu’intervention en santé. Nous avons trouvé une étude sur l’utilisation du cirque en tant qu’intervention en milieu scolaire. Cette étude a démontré une augmentation de l’estime personnelle des enfants grâce à l’intervention. Nous avons trouvé une étude sur l’utilisation du cirque en tant qu’intervention sur une réserve amérindienne. Cette étude présente des résultats qualitatifs non spécifiques au programme du cirque social. Les autres articles répertoriés n’étaient que des descriptions du cirque social. Un site web concernant l’utilisation du cirque social pour

Participation des médecins généralistes de la province de Benimellal (Maroc) dans le dépistage du cancer du col

PubMed Central

Nani, Samira; Benallal, Mohamed; Hassoune, Samira; Kissi, Dounia; Maaroufi, Abderrahmane

2013-01-01

Introduction Au Maroc, chaque année il y aurait environ 2000 nouveaux cas de cancer du col et les 2/3 des cas sont pris en charge à un stade très avancé. Nous avons mené une étude transversale, exhaustive incluant les 71 médecins généralistes exerçant dans les établissements de soins de santé de base du secteur public et privé de la province de Benimellal. Le but était d’évaluer leurs connaissances et leur participation au dépistage du cancer du col. Méthodes Nous avons mené une étude transversale, exhaustive incluant les 71 médecins généralistes exerçant dans les établissements de soins de santé de base du secteur public et privé de la province de Benimellal. Le but était d’évaluer leurs connaissances et leur participation au dépistage du cancer du col. Résultats Le niveau de connaissance était relativement modeste, 22 médecins généraliste avaient répondu à la question sur l'incidence du cancer du col au Maroc, Parmi eux (81,8%) avaient donné une réponse incorrecte. L'Herpes Papilloma virus comme facteur de risque du cancer du col a été identifié par seulement 21% des médecins généralistes. La participation au dépistage était également défaillante, 92,8% n'avaient jamais pratiqué le FCV chez leurs patientes à cause principalement du manque de formation (95,5%). Conclusion Les résultats montrent la nécessité d'améliorer les connaissances théoriques et pratique des médecins généralistes concernant le dépistage du cancer du col. PMID:23785557

Séroprévalence et facteurs associés à l’acceptation du Conseil et Dépistage Volontaire du VIH chez l’enfant à Lubumbashi, République Démocratique du Congo

PubMed Central

Ngwej, Dieudonné Tshikwej; Mukuku, Olivier; Malonga, Françoise Kaj; Luboya, Oscar Numbi; Kakoma, Jean-Baptiste Sakatolo; Wembonyama, Stanis Okitotsho

2017-01-01

Résumé Introduction Malgré le dépistage du VIH proposé lors de la naissance ou au cours des consultations préscolaires, la proportion des enfants qui croissent ou décèdent sous statut sérologique au VIH inconnu est importante en République Démocratique du Congo (RDC). L’objectif de cette étude était de déterminer la séroprévalence au cours d’un dépistage volontaire et d’identifier les facteurs associés à l’acceptation du conseil et dépistage du VIH (CDV) en dehors de la maladie ou de toute exposition au VIH dans une population pédiatrique à Lubumbashi, RDC. Méthodes Il s’agissait d’une étude prospective transversale à visée analytique menée du 1er août 2006 au 31 septembre 2007. Elle avait été réalisée dans 4 centres communautaires de CDV répartis dans 4 zones de santé de la ville de Lubumbashi en RDC (Lubumbashi, Ruashi, Kampemba et de Kenya). L’étude avait consisté à faire le dépistage volontaire du VIH chez les enfants de moins de 15 ans. Les caractéristiques sociodémographiques et les paramètres relatifs au conseil et dépistage volontaire ont été étudiés. Les analyses statistiques descriptives usuelles et une régression logistique ont été réalisées. Résultats Sur 463 enfants dépistés du VIH, 41 (8,9%; IC 95%: 6,5%-11,9%) ont été testés positifs. L’acceptation du conseil et dépistage volontaire du VIH en dehors de la maladie ou de l’exposition au VIH était significativement plus élevée lorsque l’enfant était âgé de plus de 2 ans (Odds ratio ajusté (ORa) = 3,6 [IC 95%: 1,1-12,2]), lorsque le statut sérologique du VIH des parents était négatif ou inconnu (ORa = 27,4 [IC 95%: 9,4-80,0]), lorsque l’un ou l’autre ou les deux parents biologiques étaient en vie (ORa = 24,9 [IC 95%: 2,4-250,8]) et lorsque la connaissance du lieu de dépistage était fait par des moyens autres que le professionnel de santé (ORa = 2,9 [IC 95%: 1,0-7,9]). Conclusion Notre étude montre une forte

Identification des parametres du moteur de l'avion Cessna Citation X pour la phase de croisiere a partir des tests en vol et a base des reseaux de neurones =

NASA Astrophysics Data System (ADS)

Zaag, Mahdi

La disponibilite des modeles precis des avions est parmi les elements cles permettant d'assurer leurs ameliorations. Ces modeles servent a ameliorer les commandes de vol et de concevoir de nouveaux systemes aerodynamiques pour la conception des ailes deformables des avions. Ce projet consiste a concevoir un systeme d'identification de certains parametres du modele du moteur de l'avion d'affaires americain Cessna Citation X pour la phase de croisiere a partir des essais en vol. Ces essais ont ete effectues sur le simulateur de vol concu et fabrique par CAE Inc. qui possede le niveau D de la dynamique de vol. En effet, le niveau D est le plus haut niveau de precision donne par l'autorite federale de reglementation FAA de l'aviation civile aux Etats-Unis. Une methodologie basee sur les reseaux de neurones optimises a l'aide d'un algorithme intitule le "grand deluge etendu" est utilisee dans la conception de ce systeme d'identification. Plusieurs tests de vol pour differentes altitudes et differents nombres de Mach ont ete realises afin de s'en servir comme bases de donnees pour l'apprentissage des reseaux de neurones. La validation de ce modele a ete realisee a l'aide des donnees du simulateur. Malgre la nonlinearite et la complexite du systeme, les parametres du moteur ont ete tres bien predits pour une enveloppe de vol determinee. Ce modele estime pourrait etre utilise pour des analyses de fonctionnement du moteur et pourrait assurer le controle de l'avion pendant cette phase de croisiere. L'identification des parametres du moteur pourrait etre realisee aussi pour les autres phases de montee et de descente afin d'obtenir son modele complet pour toute l'enveloppe du vol de l'avion Cessna Citation X (montee, croisiere, descente). Cette methode employee dans ce travail pourrait aussi etre efficace pour realiser un modele pour l'identification des coefficients aerodynamiques du meme avion a partir toujours des essais en vol. None None None

L'Aventure du LHC

DOE Office of Scientific and Technical Information (OSTI.GOV)

None

2010-06-11

Cette présentation s’adressera principalement aux personnes qui ont construit le LHC. La construction du LHC fut longue et difficile. De nombreux problèmes sont apparus en cours de route. Tous ont été résolus grâce au dévouement et à l’engagement du personnel et des collaborateurs. Je reviendrai sur les coups durs et les réussites qui ont marqués ces 15 dernières années et je vous montrerai combien cette machine, le fruit de vos efforts, est extraordinaire.

Non-destructive analysis of DU content in the NIF hohlraums

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gharibyan, Narek; Moody, Ken J.; Shaughnessy, Dawn A.

2015-12-16

The advantage of using depleted uranium (DU) hohlraums in high-yield deuterium-tritium (DT) shots at the National Ignition Facility (NIF) is addressed by Döppner, et al., in great detail [1]. This DU based hohlraum incorporates a thin layer of DU, ~7 μm thick, on the inner surface along with a thin layer of a gold coating, ~0.7 μm thick, while the outer layer is ~22 μm thick gold. A thickness measurement of the DU layer can be performed using an optical microscope where the total DU weight can be computed provided a uniform DU layer. However, the uniformity of the thicknessmore » is not constant throughout the hohlraum since CAD drawing calculations of the DU weight do not agree with the computed values from optical measurements [2]. Therefore, a non-destructive method for quantifying the DU content in hohlraums has been established by utilizing gamma-ray spectroscopy. The details of this method, along with results from several hohlraums, are presented in this report.« less

Portage vaginal du streptocoque du groupe B chez la femme enceinte au niveau de la région de Marrakech

PubMed Central

Bassir, Ahlam; Dhibou, Hanane; Farah, Majdi; Mohamed, Lharmis; Amal, Addebous; Nabila, Souraa; Abderahim, Aboulfalah; Asmouki, Hamid; Soummani, Abderraouf

2016-01-01

Introduction Le streptocoque du groupe B est le principal agent impliqué dans les infections materno-fœtales, les septicémies et les méningites du nouveau-né à terme. L'objectif est de déterminer le taux de portage maternel du streptocoque du groupe B (SGB) à terme. Méthodes Un prélèvement vaginal a été réalisé de manière prospective chez 275 parturientes lors de l'entrée en salle d'accouchement sur une période de 06 mois. Résultats Le taux de portage était de 20,2%. Le portage était variable en fonction de l’âge gestationnel, il constitue 57.5% entre 37 et 38 semaines d'aménorrhée. Aucun des facteurs de risque n'a était statistiquement prédictif du portage maternel du SGB. Conclusion Le dépistage doit être réalisé à partir de 37 semaines d'aménorrhée, et comme le portage est intermittent, un prélèvement négatif ne garantirait pas que le portage soit négatif à l'accouchement. PMID:27222693

Cirque du Monde as a health intervention

PubMed Central

Fournier, Cynthia; Drouin, Mélodie-Anne; Marcoux, Jérémie; Garel, Patricia; Bochud, Emmanuel; Théberge, Julie; Aubertin, Patrice; Favreau, Gil; Fleet, Richard

2014-01-01

Abstract Objective To present Cirque du Soleil’s social circus program, Cirque du Monde, to explore its potential as a primary health care tool for family physicians. Data sources A review of the literature in PubMed, the Cochrane Library, PsycINFO, LaPresse, Eureka, Google Scholar, and Érudit using the key words circus, social circus, Cirque du Monde, and Cirque du Soleil; a Montreal-based initiative, Espace Transition, modeled on Cirque du Monde; and personal communication with Cirque du Soleil’s Social Circus Training Advisor. Study selection The first 50 articles or websites identified for each key word in each of the databases were examined on the basis of their titles and abstracts in the case of articles, and on the basis of their titles and page content in the case of websites. Articles and websites that explored an aspect of social circuses or that described an intervention that involved circuses were then retained for analysis. Because all literature on social circuses was searched, no criterion for year of publication was used. Synthesis No articles on the social circus as a health intervention were found. One study on the use of the circus as an intervention in schools was identified. It demonstrated an increase in self-esteem in the children who took part. One study on the use of the circus in a First Nations community was found; it contained nonspecific, qualitative findings. The other articles identified were merely descriptions of social circuses. One website was identified on the use of the social circus to help youth who had been treated in a hospital setting for major psychiatric disorders to re-enter the community. The team in the pediatric psychiatry department at Centre Hospitalier Universitaire Sainte-Justine, the children’s hospital in Montreal, Que, was contacted; they were leading this project, called Espace Transition. The unpublished preliminary findings of its pilot project demonstrate substantial improvements in overall patient

L'Aventure du LHC

ScienceCinema

None

2018-05-16

Cette présentation s’adressera principalement aux personnes qui ont construit le LHC. La construction du LHC fut longue et difficile. De nombreux problèmes sont apparus en cours de route. Tous ont été résolus grâce au dévouement et à l’engagement du personnel et des collaborateurs. Je reviendrai sur les coups durs et les réussites qui ont marqués ces 15 dernières années et je vous montrerai combien cette machine, le fruit de vos efforts, est extraordinaire.

Global synthesis of volcano deformation: Results of the Volcano Deformation Task Force

NASA Astrophysics Data System (ADS)

Pritchard, M. E.; Jay, J.; Biggs, J.; Ebmeier, S. K.; Delgado, F.

2013-12-01

Ground deformation in volcanic regions is being observed more frequently -- the number of known deforming volcanoes has increased from 44 in 1997 to more than 210 in 2013 thanks in large part thanks to the availability of satellite InSAR observations. With the launch of new SAR satellites in the coming years devoted to global deformation monitoring, the number of well-studied episodes of volcano deformation will continue to increase. But evaluating the significance of the observed deformation is not always straightforward -- how often do deformation episodes lead to eruption? Are there certain characteristics of the deformation or the volcano that make the linkage between deformation and eruption more robust -- for example the duration or magnitude of the ground deformation and/or the composition and tectonic setting of the volcano? To answer these questions, a global database of volcano deformation events is needed. Recognizing the need for global information on volcano deformation and the opportunity to address it with InSAR and other techniques, we formed the Volcano Deformation Database Task force as part of Global Volcano Model. The three objectives of our organization are: 1) to compile deformation observations of all volcanoes globally into appropriate formats for WOVOdat and the Global Volcanism Program of the Smithsonian Institution. 2) document any relation between deformation events and eruptions for the Global assessment of volcanic hazard and risk report for 2015 (GAR15) for the UN. 3) to better link InSAR and other remote sensing observations to volcano observatories. We present the first results from our global study of the relation between deformation and eruptions, including case studies of particular eruptions. We compile a systematically-observed catalog of >500 volcanoes with observation windows up to 20 years. Of 90 volcanoes showing deformation, 40 erupted. The positive predictive value (PPV = 0.44) linking deformation and eruption on this

Dedicated Caravan Sites for French Gens du Voyage

PubMed Central

2017-01-01

Abstract In France, gens du voyage (“people who travel” or “travellers”) is a term used by the government to categorize various itinerant populations, the majority of which are diverse Romani groups. People categorized as gens du voyage are legally required to reside in particular locations called “dedicated caravan sites.” Parliamentary debates about these dedicated caravan sites have clarified that one of the objectives of such sites is to help fulfill the gens du voyage’s right to health. However, there is a significant gap between the officially stated goals of such sites and the reality of life within them. This paper draws on research finding that the conditions in most dedicated caravan sites do not conform with the rights of gens du voyage to acceptable sanitary conditions and other underlying determinants of health. PMID:29302165

Mechanical Failure Mode of Metal Nanowires: Global Deformation versus Local Deformation

PubMed Central

Ho, Duc Tam; Im, Youngtae; Kwon, Soon-Yong; Earmme, Youn Young; Kim, Sung Youb

2015-01-01

It is believed that the failure mode of metal nanowires under tensile loading is the result of the nucleation and propagation of dislocations. Such failure modes can be slip, partial slip or twinning and therefore they are regarded as local deformation. Here we provide numerical and theoretical evidences to show that global deformation is another predominant failure mode of nanowires under tensile loading. At the global deformation mode, nanowires fail with a large contraction along a lateral direction and a large expansion along the other lateral direction. In addition, there is a competition between global and local deformations. Nanowires loaded at low temperature exhibit global failure mode first and then local deformation follows later. We show that the global deformation originates from the intrinsic instability of the nanowires and that temperature is a main parameter that decides the global or local deformation as the failure mode of nanowires. PMID:26087445

Deformation measurement for a rotating deformable lap based on inverse fringe projection

NASA Astrophysics Data System (ADS)

Liao, Min; Zhang, Qican

2015-03-01

The active deformable lap (also namely stressed lap) is an efficient polishing tool in optical manufacturing. To measure the dynamic deformation caused by outside force on a deformable lap is important and helpful to the opticians to ensure the performance of a deformable lap as expected. In this paper, a manual deformable lap was designed to simulate the dynamic deformation of an active stressed lap, and a measurement system was developed based on inverse projected fringe technique to restore the 3D shape. A redesigned inverse fringe has been projected onto the surface of the measured lap, and the deformations of the tested lap become much obvious and can be easily and quickly evaluated by Fourier fringe analysis. Compared with the conventional projection, this technique is more obvious, and it should be a promising one in the deformation measurement of the active stressed lap in optical manufacturing.

Polymorphisme de l'apolipoprotéine E dans la population du nord du Maroc: fréquence et influence sur les paramètres lipidiques

PubMed Central

Benyahya, Fatiha; Barakat, Amina; Ghailani, Naima; Bennani, Mohcine

2013-01-01

Introduction L'objectif de ce travail est de déterminer les fréquences alléliques et génotypiques des sites polymorphes situés dans le gène de l'apolipoprotéine E (apo E) ainsi que leur impact sur les paramètres cliniques et lipidiques dans un échantillon de la population du nord du Maroc cliniquement diagnostiqué ADH. Méthodes Le génotype de l'apo E a été analysé par séquençage direct chez 46 patients cliniquement diagnostiqués ADH selon les critères standards. Résultats Les fréquences des allèles epsilon 3, epsilon 2 et epsilon 4 ont été respectivement 78.3%, 2.2% et 19.6%. La fréquence de l'allèle epsilon 4 est très élevée chez la population du nord du Maroc en comparaison avec les populations des autres régions marocaines. Elle est similaire à celle rapportée dans les pays de l'Europe du nord. Les taux du cholestérol total, du cholestérol LDL ainsi que la présence des xanthomes et les maladies cardiovasculaires ne différent pas entre les génotypes de l'apoE. En revanche, les résultats ont montré une influence de l'allèle epsilon4 sur le taux des triglycérides chez les sujets obèses. Conclusion Le génotype de l'apoE ne peut expliquer le phénotype clinique et biochimique présenté par des patients du Nord du Maroc cliniquement diagnostiqués ADH. PMID:24396563

Étude des déterminants individuels de l’adoption du dossier de santé électronique du Québec

PubMed Central

Mezni, H; M-P, Gagnon; Duplantie, J

2016-01-01

Résumé Objectif Selon des études précédentes, les dossiers de santé électroniques peuvent améliorer l’efficacité, la sécurité et la qualité de la prise en charge médicale. Cependant, les prestataires de soins restent réticents quant à son utilisation, ce qui limite son impact sur le système de santé. La présente étude avait pour objectif d’évaluer les perceptions des médecins face au dossier de santé du Québec. Méthodes À partir d’une revue de la littérature sur les facteurs influençant l’adoption des nouvelles technologies de l’information et des communications (NTIC) en général et de la cybersanté en particulier, nous avons élaboré un questionnaire semi-structuré. Au total, 12 médecins utilisateurs potentiels du dossier de santé du Québec (DSQ) ont complété et retourné le questionnaire. Par la suite, nous avons opéré une analyse thématique de contenu, suivie par une théorisation des concepts obtenus. Résultats L’intention d’adopter le DSQ est influencée positivement par l’utilité perçue, la facilité d’utilisation perçue, la démonstrabilité des résultats, la compatibilité du système avec la pratique et l’autoefficacité informatique perçue par les médecins. Inversement, la résistance au changement influence négativement l’adoption du DSQ par les médecins. Conclusion L’identification des déterminants de l’adoption du dossier de santé du Québec est cruciale pour les responsables du secteur de la santé au Québec. Il sera ainsi possible de saisir les attentes des utilisateurs potentiels et d’ajuster les stratégies d’implantation en vue de favoriser une meilleure intégration de cette technologie dans les pratiques médicales. PMID:27867453

Deformation twinning in a creep-deformed nanolaminate structure

NASA Astrophysics Data System (ADS)

Hsiung, Luke L.

2010-10-01

The underlying mechanism of deformation twinning occurring in a TiAl-(γ)/Ti3Al-(α2) nanolaminate creep deformed at elevated temperatures has been studied. Since the multiplication and propagation of lattice dislocations in both γ and α2 thin lamellae are very limited, the total flow of lattice dislocations becomes insufficient to accommodate the accumulated creep strains. Consequently, the movement of interfacial dislocations along the laminate interfaces, i.e., interface sliding, becomes an alternative deformation mode of the nanolaminate structure. Pile-ups of interfacial dislocations occur when interfacial ledges and impinged lattice dislocations act as obstacles to impede the movement of interfacial dislocations. Deformation twinning can accordingly take place to relieve a stress concentration resulting from the pile-up of interfacial dislocations. An interface-controlled twinning mechanism driven by the pile-up and dissociation of interfacial dislocations is accordingly proposed.

Le kyste hydatique du cordon spermatique: une localisation exceptionnelle

PubMed Central

Hamdane, Mohamed Moncef; Bougrine, Fethi; Msakni, Issam; Dhaoui-Ghozzi, Amen; Bouziani, Ammar

2011-01-01

L’ hydatidose est une anthropo-zoonose due au développement chez l'homme de la forme larvaire du taenia Echinococcus granulosis. La plupart des kystes hydatiques se localisent dans le foie et les poumons. Le kyste hydatique du cordon spermatique est extrêmement rare avec seulement 4 cas rapportés dans la littérature. Les auteurs rapportent dans cet article un nouveau cas d'hydatidose du cordon spermatique. Il s'agissait d'un homme de 40 ans qui consultait pour des douleurs scrotales évoluant depuis huit mois. L'examen clinique a mis en évidence une tuméfaction mobile, inguino-scrotale, droite. L’échographie testiculaire a objectivé une hernie inguinale droite associée à deux kystes épididymaires bilatéraux. Le patient a été opéré pour cure de son hernie avec découverte en per-opératoire d'un kyste du cordon spermatique qui a été réséqué. L'examen anatomopathologique a conclu à une hydatidose du cordon spermatique. PMID:22384304

Acceptabilité du test VIH proposé aux nourrissons dans les services pédiatriques, en Côte d'Ivoire, Significations pour la couverture du diagnostic pédiatrique

PubMed Central

Oga, Maxime; Brou, Hermann; Dago-Akribi, Hortense; Coffie, Patrick; Amani-Bossé, Clarisse; Ékouévi, Didier; Yapo, Vincent; Menan, Hervé; Ndondoki, Camille; Timité-Konan, M.; Leroy, Valériane

2014-01-01

Résumé Problème: Le dépistage VIH chez les enfants a rarement été au centre des préoccupations des chercheurs. Quand le dépistage pédiatrique a retenu l'attention, cela a été pour éclairer seulement sur les performances diagnostiques en ignorant même que le test pédiatrique comme bien d'autres peut s'accepter ou se refuser. Cet article met au cœur de son analyse les raisons qui peuvent expliquer qu'on accepte ou qu'on refuse de faire dépister son enfant. Objectif: Etudier chez les parents, les mères, les facteurs explicatifs de l'acceptabilité du test VIH des nourrissons de moins de six mois. Méthodes: Entretien semi-directif à passages répétés avec les parents de nourrissons de moins de six mois dans les formations sanitaires pour la pesée/vaccination et les consultations pédiatriques avec proposition systématique d'un test VIH pour leur nourrisson. Résultats: Nous retenons que la réalisation effective du test pédiatrique du VIH chez le nourrisson repose sur trois éléments. Primo, le personnel de santé par son discours (qui dénote de ses connaissances et perceptions même sur l'infection) orienté vers les mères influence leur acceptation ou non du test. Secundo, la mère qui par ses connaissances et perceptions même sur le VIH, dont le statut particulier, l'impression de bien-être chez elle et son enfant influence toute réalisation du test pédiatrique VIH. Tertio, l'environnement conjugal de la mère, particulièrement caractérisé par les rapports au sein du couple, sur la facilité de parler du test VIH et sa réalisation chez les deux parents ou chez la mère seulement sont autant de facteurs qui influencent la réalisation effective du dépistage du VIH chez l'enfant. Le principe préventif du VIH, et le désir de faire tester l'enfant ne suffisent pas à eux seuls pour aboutir à sa réalisation effective, selon certaines mères confrontées au refus du conjoint. A l'opposé, les autres mères refusant la r

The properties of Q-deformed hyperbolic and trigonometric functions in quantum deformation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Deta, U. A., E-mail: utamaalan@yahoo.co.id, E-mail: utamadeta@unesa.ac.id; Suparmi

2015-09-30

Quantum deformation has been studied due to its relation with applications in nuclear physics, conformal field theory, and statistical-quantum theory. The q-deformation of hyperbolic function was introduced by Arai. The application of q-deformed functions has been widely used in quantum mechanics. The properties of this two kinds of system explained in this paper including their derivative. The graph of q-deformed functions presented using Matlab. The special case is given for modified Poschl-Teller plus q-deformed Scarf II trigonometry potentials.

Brain stem hypoplasia associated with Cri-du-Chat syndrome.

PubMed

Hong, Jin Ho; Lee, Ha Young; Lim, Myung Kwan; Kim, Mi Young; Kang, Young Hye; Lee, Kyung Hee; Cho, Soon Gu

2013-01-01

Cri-du-Chat syndrome, also called the 5p-syndrome, is a rare genetic abnormality, and only few cases have been reported on its brain MRI findings. We describe the magnetic resonance imaging findings of a 1-year-old girl with Cri-du-Chat syndrome who showed brain stem hypoplasia, particularly in the pons, with normal cerebellum and diffuse hypoplasia of the cerebral hemispheres. We suggest that Cri-du-Chat syndrome chould be suspected in children with brain stem hypoplasia, particularly for those with high-pitched cries.

Information non précise sur la taille du pénis en République Démocratique du Congo: à propos de 21 sources

PubMed Central

Mulenga, Philippe Cilundika; Kazadi, Alex Bukasa

2016-01-01

Introduction La taille du pénis constitue une préoccupation de beaucoup des gens actuellement et certains ne sont pas satisfaits de la dimension de leur pénis comme le montre l’étude de Tiggemann en 2008. Il existe relativement peu d'études sur le pénis en érection. Cela peut refléter les tabous culturels des chercheurs ou des médecins en interaction avec les hommes qui sont dans un état d’excitation sexuelle. Toutes fois, il est important pour les personnes qui annoncent des détails sur la taille du pénis d’annoncer d’abord les repères de la mesure du pénis puis ensuite donner les chiffres que proposent les chercheurs. Méthodes Notre enquête de type descriptif transversale s’est effectuée dans les deux grandes villes de la République Démocratique du Congo à savoir la ville de Kinshasa et la ville de Lubumbashi, pendant une période de deux ans soit de Mai 2014 à Mai 2016. Au total, 21 sources d’information ont constitué notre échantillon dont 8 à Kinshasa et 13 à Lubumbashi et nous avons trouvé cela suffisant car les sujets à caractère sexuel sont souvent rares chez nous. Les paramètres étudiés étaient: la nature de la source, la précision de la technique de la mesure, la présence de référence bibliographique, la longueur annoncée du pénis. Résultats La majorité des sources d’information sont faites des émissions de radio et de télévision (23,8%), ceci pourra s’expliquer par le fait que dans notre milieu il y a de plus en plus des chaines de radio et télévision et surtout dans les grandes villes. Concernant la précision de la technique de la mesure du pénis lors du partage du message sur la taille du pénis, l’étude nous montre que la majorité des sources d’information ne signale pas cela lorsqu’elles annoncent la taille du pénis au public soit 85,7%. Plusieurs sources ne déclarent pas les références bibliographiques (57,1%). Lorsqu’on regarde même les chiffres de la taille du p

Models of determining deformations

NASA Astrophysics Data System (ADS)

Gladilin, V. N.

2016-12-01

In recent years, a lot of functions designed to determine deformation values that occur mostly as a result of settlement of structures and industrial equipment. Some authors suggest such advanced mathematical functions approximating deformations as general methods for the determination of deformations. The article describes models of deformations as physical processes. When comparing static, cinematic and dynamic models, it was found that the dynamic model reflects the deformation of structures and industrial equipment most reliably.

Cholestéatome du méat acoustique externe

PubMed Central

Azeddine, Lachkar; Aabach, Ahmed; Chouai, Mohamed; Elayoubi, Fahd; Ghailan, Mohamed Rachid

2016-01-01

Le cholestéatome du méat acoustique externe se définit comme une accumulation de kératine en regard d’une érosion osseuse de nature ostéitique. C’est une entité otologique rare ou peut diagnostiquée. Le but de notre travail est d’illustrer sur la base d’un cas un cholestéatome du méat acoustique externe. Il s’agit d’un patient âgé de 65 ans diabétique et hypertendu sous traitement, présentant depuis 3 mois une otalgie droite intense, insomniante, avec hypoacousie, otorrhée purulente minime et paralysie faciale droite grade V. Le diagnostic évoqué était dans un premier temps celui d’otite externe maligne. Il a été mis sous traitement antibiotique sans amélioration. L’examen otologique a trouvé une lésion ulcéro-bourgeonnante de la paroi postérieure du méat acoustique externe droit, une biopsie systématique de la lésion a été pratiquée et a conclu à un cholestéatome. Le patient a bénéficié d’une tympanoplastie en technique ouverte. Le cholestéatome du méat acoustique externe est rare, la symptomatologie clinique n’est pas spécifique, le scanner des rocher est d’un grand apport pour le diagnostic positif montrant un cratère osseux du méat acoustique externe. Le traitement dépend de l’extension des lésions allant des simples soins locaux à une tympanoplastie en technique ouverte. Le cholestéatome du méat acoustique externe peut revêtir plusieurs aspects, et prêter confusion avec d’autres pathologies du méat acoustique externe. PMID:28154624

Cancer du sein au Maroc: profil phénotypique des tumeurs

PubMed Central

Khalil, Ahmadaye Ibrahim; Bendahhou, Karima; Mestaghanmi, Houriya; Saile, Rachid; Benider, Abdellatif

2016-01-01

Le cancer du sein est le plus fréquent chez la femme et figure parmi les principales causes de mortalité liées au cancer. La curabilité de ce type tumoral est en augmentation, grâce aux programmes de dépistage et aux progrès thérapeutiques, qui ont certes augmenté la survie des patients. Mais des défis restent à relever en rapport avec l’instabilité phénotypique des cellules cancéreuses. L’objectif de ce travail est d’étudier le profil phénotypique du cancer du sein chez les patients pris en charge au Centre Mohammed VI pour le traitement des Cancers, durant les années 2013-2014. Il s’agit d’une étude transversale sur deux années, incluant les cas du cancer du sein pris en charge au Centre. Le recueil des données était fait à partir des dossiers des patients et analysés par le logiciel Epi Info. 1277 patients ont été pris en charge au sein de notre centre. 99,5% des cas de sexe féminin, l’âge moyen était 50,20 ± 11,34 ans. Le type histologique le plus fréquent était le carcinome canalaire infiltrant (80,7% des cas). Le stade diagnostic était précoce (56,9%). Le phénotype moléculaire le plus fréquent était le luminal A (41,4% des cas). Le luminal B, le HER2 et les triples négatifs étaient dans respectivement 10,4%, 6,3%, 11,2% des cas. L’étude du phénotype tumoral des patients atteints du cancer du sein permet l’orientation du clinicien dans le choix du traitement, et des décideurs dans la planification de programmes de lutte contre cette pathologie. PMID:28292037

Identification d'une loi thermo-élasto-viscoplastique en vue de la modélisation du laminage à chaud du cuivre

NASA Astrophysics Data System (ADS)

Moureaux, P.; Moto Mpong, S.; Remy, M.; Bouffioux, C.; Lecomte-Beckers, J.; Habraken, A. M.

2002-12-01

la mise au point d'un modèle de simulation de la dernière passe du laminage à chaud du cuivre ne présente à priori pas de problème du point de vue numérique pour un code d'éléments finis non linéaire. La collecte d'informations précises tant sur le procédé industriel que sur le comportement du matériau est par contre une opération non triviale. Cet article présente les diverses méthodes expérimentales mises en œuvre pour caractériser le matériau : essais de compression à chaud, mesures d'analyse thermique différentielle, essais de dilatométrie et de diffusivité. Les méthodes permettant d'identifier les paramètres de la loi élasto-visco-plastique de type Norton-Hoff à partir des essais sont présentées et une analyse bibliographique investigue le problème de la détermination du module de Young à haute température. Tant les hypothèses supplémentaires relatives au procédé et nécessaires au modèle que les résultats finaux sont résumés.

Canonical correlation analysis of factors involved in the occurrence of peptic ulcers.

PubMed

Bayyurt, Nizamettin; Abasiyanik, M Fatih; Sander, Ersan; Salih, Barik A

2007-01-01

The impact of risk factors on the development of peptic ulcers has been shown to vary among different populations. We sought to establish a correlation between these factors and their involvement in the occurrence of peptic ulcers for which a canonical correlation analysis was applied. We included 7,014 patient records (48.6% women, 18.4% duodenal ulcer [DU], 4.6% gastric ulcer [GU]) of those underwent upper gastroendoscopy for the last 5 years. The variables measured are endoscopic findings (DU, GU, antral gastritis, erosive gastritis, pangastritis, pyloric deformity, bulbar deformity, bleeding, atrophy, Barret esophagus and gastric polyp) and risk factors (age, gender, Helicobacter pylori infection, smoking, alcohol, and nonsteroidal anti-inflammatory drugs [NSAIDs] and aspirin intake). We found that DU had significant positive correlation with bulbar deformity (P=2.6 x 10(-23)), pyloric deformity (P=2.6 x 10(-23)), gender (P=2.6 x 10(-23)), H. pylori (P=1.4 x 10(-15)), bleeding (P=6.9 x 10(-15)), smoking (P=1.4 x 10(-7)), aspirin use (P=1.1 x 10(-4)), alcohol intake (P=7.7 x 10(-4)), and NSAIDs (P=.01). GU had a significantly positive correlation with pyloric deformity (P=1,6 x 10(-15)), age (P=2.6 x 10(-14)), bleeding (P=3.7 x 10(-8)), gender (P=1.3 x 10(-7)), aspirin use (P=1.1 x 10(-6)), bulbar deformity (P=7.4 x 10(-4)), alcohol intake (P=.03), smoking (P=.04), and Barret esophagus (P=.03). The level of significance was much higher in some variables with DU than with GU and the correlations with GU in spite of being highly significant the majority, were small in magnitude. In conclusion, Turkish patients with the following endoscopic findings bulbar deformity and pyloric deformity are high-risk patients for peptic ulcers with the risk of the occurrence of DU being higher than that of GU. Factors such as H. pylori, smoking, alcohol use, and NSAIDs use (listed in a decreasing manner) are risk factors that have significant impact on the occurrence of DU

Properties, use and health effects of depleted uranium (DU): a general overview.

PubMed

Bleise, A; Danesi, P R; Burkart, W

2003-01-01

Depleted uranium (DU), a waste product of uranium enrichment, has several civilian and military applications. It was used as armor-piercing ammunition in international military conflicts and was claimed to contribute to health problems, known as the Gulf War Syndrome and recently as the Balkan Syndrome. This led to renewed efforts to assess the environmental consequences and the health impact of the use of DU. The radiological and chemical properties of DU can be compared to those of natural uranium, which is ubiquitously present in soil at a typical concentration of 3 mg/kg. Natural uranium has the same chemotoxicity, but its radiotoxicity is 60% higher. Due to the low specific radioactivity and the dominance of alpha-radiation no acute risk is attributed to external exposure to DU. The major risk is DU dust, generated when DU ammunition hits hard targets. Depending on aerosol speciation, inhalation may lead to a protracted exposure of the lung and other organs. After deposition on the ground, resuspension can take place if the DU containing particle size is sufficiently small. However, transfer to drinking water or locally produced food has little potential to lead to significant exposures to DU. Since poor solubility of uranium compounds and lack of information on speciation precludes the use of radioecological models for exposure assessment, biomonitoring has to be used for assessing exposed persons. Urine, feces, hair and nails record recent exposures to DU. With the exception of crews of military vehicles having been hit by DU penetrators, no body burdens above the range of values for natural uranium have been found. Therefore, observable health effects are not expected and residual cancer risk estimates have to be based on theoretical considerations. They appear to be very minor for all post-conflict situations, i.e. a fraction of those expected from natural radiation.

Analysis of Mining Terrain Deformation Characteristics with Deformation Information System

NASA Astrophysics Data System (ADS)

Blachowski, Jan; Milczarek, Wojciech; Grzempowski, Piotr

2014-05-01

Mapping and prediction of mining related deformations of the earth surface is an important measure for minimising threat to surface infrastructure, human population, the environment and safety of the mining operation itself arising from underground extraction of useful minerals. The number of methods and techniques used for monitoring and analysis of mining terrain deformations is wide and increasing with the development of geographical information technologies. These include for example: terrestrial geodetic measurements, global positioning systems, remote sensing, spatial interpolation, finite element method modelling, GIS based modelling, geological modelling, empirical modelling using the Knothe theory, artificial neural networks, fuzzy logic calculations and other. The aim of this paper is to introduce the concept of an integrated Deformation Information System (DIS) developed in geographic information systems environment for analysis and modelling of various spatial data related to mining activity and demonstrate its applications for mapping and visualising, as well as identifying possible mining terrain deformation areas with various spatial modelling methods. The DIS concept is based on connected modules that include: the spatial database - the core of the system, the spatial data collection module formed by: terrestrial, satellite and remote sensing measurements of the ground changes, the spatial data mining module for data discovery and extraction, the geological modelling module, the spatial data modeling module with data processing algorithms for spatio-temporal analysis and mapping of mining deformations and their characteristics (e.g. deformation parameters: tilt, curvature and horizontal strain), the multivariate spatial data classification module and the visualization module allowing two-dimensional interactive and static mapping and three-dimensional visualizations of mining ground characteristics. The Systems's functionality has been presented on

Le traumatisme du colon: l'expérience du CHU Hassan II de Fès

PubMed Central

Benjelloun, El Bachir; Hafid, Hasnai; Karim, Ibnmajdoub; Ousadden, Abdelmalek; Mazaz, Khalid; Taleb, Kahlid Ait

2012-01-01

Introduction Les traumatismes du colon sont associés à un risque majeur de complications septiques et de mortalité. Le but de notre étude est d’évaluer les circonstances, la prise en charge, le suivi et les facteurs pronostic de morbidité postopératoire des malades victimes d'un traumatisme colique. Méthodes Il s'agit d'une étude rétrospective sur une série de 49 patients opérés pour des plaies coliques aux services de chirurgie viscérale du CHU HASSAN II de Fès sur une période de 8 ans de juillet 2003 à juillet 2011. Résultats L’âge moyen de nos patients était de 25ans (16-70) avec une nette prédominance masculine (93.8%). Les plaies coliques secondaires à un traumatisme par arme blanche représentent 85% des cas (42 patients), suivi par les plaies iatrogènes au cours d'une coloscopie chez 6 patients (13%), puis les contusions abdominales chez 1 patient (2%). Les parties du cadre colique les plus touchées étaient le colon transverse chez 19 patients (38%) et le colon descendant chez 12 patients (24, 5%). Le colon sigmoïde était le segment le plus touché au cours d'une coloscopie4/6. Quarante-deux patients (85%) ont eu une suture primaire des plaies coliques, six patients (13%) une diversion fécale et un patient (2%) une résection-anastomose. Deux patients (4%) sont décédés suite à un choc septique. La morbidité globale était de 38,7% dominé essentiellement par l'infection de la paroi chez 14 patients et une péritonite post opératoire chez 3 patients. L'analyse univarié a montré une différence significatif en terme d'infection de la paroi entre le groupe colostomie versus suture simple (50% vs 20,9% p<0,05). L'atteinte du colon gauche et la réalisation d'une colostomie sont associés à un risque plus élevés de complications postopératoires. Conclusion La suture primaire peut être effectuée avec un faible taux de complications postopératoire chez la majorité des patients suite à un traumatisme du colon. PMID

Deformation mechanisms in experimentally deformed Boom Clay

NASA Astrophysics Data System (ADS)

Desbois, Guillaume; Schuck, Bernhard; Urai, Janos

2016-04-01

Bulk mechanical and transport properties of reference claystones for deep disposal of radioactive waste have been investigated since many years but little is known about microscale deformation mechanisms because accessing the relevant microstructure in these soft, very fine-grained, low permeable and low porous materials remains difficult. Recent development of ion beam polishing methods to prepare high quality damage free surfaces for scanning electron microscope (SEM) is opening new fields of microstructural investigation in claystones towards a better understanding of the deformation behavior transitional between rocks and soils. We present results of Boom Clay deformed in a triaxial cell in a consolidated - undrained test at a confining pressure of 0.375 MPa (i.e. close to natural value), with σ1 perpendicular to the bedding. Experiments stopped at 20 % strain. As a first approximation, the plasticity of the sample can be described by a Mohr-Coulomb type failure envelope with a coefficient of cohesion C = 0.117 MPa and an internal friction angle ϕ = 18.7°. After deformation test, the bulk sample shows a shear zone at an angle of about 35° from the vertical with an offset of about 5 mm. We used the "Lamipeel" method that allows producing a permanent absolutely plane and large size etched micro relief-replica in order to localize and to document the shear zone at the scale of the deformed core. High-resolution imaging of microstructures was mostly done by using the BIB-SEM method on key-regions identified after the "Lamipeel" method. Detailed BIB-SEM investigations of shear zones show the following: the boundaries between the shear zone and the host rock are sharp, clay aggregates and clastic grains are strongly reoriented parallel to the shear direction, and the porosity is significantly reduced in the shear zone and the grain size is smaller in the shear zone than in the host rock but there is no evidence for broken grains. Comparison of microstructures

From progressive to finite deformation, and back: the universal deformation matrix

NASA Astrophysics Data System (ADS)

Provost, A.; Buisson, C.; Merle, O.

2003-04-01

It is widely accepted that any finite strain recorded in the field may be interpreted in terms of the simultaneous combination of a pure shear component with one or several simple shear components. To predict strain in geological structures, approximate solutions may be obtained by multiplying successive small increments of each elementary strain component. A more rigorous method consists in achieving the simultaneous combination in the velocity gradient tensor but solutions already proposed in the literature are valid for special cases only and cannot be used, e.g., for the general combination of a pure shear component and six elementary simple shear components. In this paper, we show that the combination of any strain components is as simple as a mouse click, both analytically and numerically. The finite deformation matrix is given by L=exp(L.Δt) where L.Δt is the time-integrated velocity gradient tensor. This method makes it possible to predict finite strain for any combination of strain components. Reciprocally, L.Δt=ln(D) , which allows to unravel the simplest deformation history that might be liable for a given finite deformation. Given the strain ellipsoid only, it is still possible to constrain the range of compatible deformation matrices and thus the range of strain component combinations. Interestingly, certain deformation matrices, though geologically sensible, have no real logarithm so cannot be explained by a deformation history implying strain rate components with constant proportions, what implies significant changes of the stress field during the history of deformation. The study as a whole opens the possibility for further investigations on deformation analysis in general, the method could be used wathever the configuration is.

TU-H-CAMPUS-JeP1-05: Dose Deformation Error Associated with Deformable Image Registration Pathways

DOE Office of Scientific and Technical Information (OSTI.GOV)

Surucu, M; Woerner, A; Roeske, J

Purpose: To evaluate errors associated with using different deformable image registration (DIR) pathways to deform dose from planning CT (pCT) to cone-beam CT (CBCT). Methods: Deforming dose is controversial because of the lack of quality assurance tools. We previously proposed a novel metric to evaluate dose deformation error (DDE) by warping dose information using two methods, via dose and contour deformation. First, isodose lines of the pCT were converted into structures and then deformed to the CBCT using an image based deformation map (dose/structure/deform). Alternatively, the dose matrix from the pCT was deformed to CBCT using the same deformation map,more » and then the same isodose lines of the deformed dose were converted into structures (dose/deform/structure). The doses corresponding to each structure were queried from the deformed dose and full-width-half-maximums were used to evaluate the dose dispersion. The difference between the FWHM of each isodose level structure is defined as the DDE. Three head-and-neck cancer patients were identified. For each patient, two DIRs were performed between the pCT and CBCT, either deforming pCT-to-CBCT or CBCT-to-pCT. We evaluated the errors associated by using either of these pathways to deform dose. A commercially available, Demons based DIR was used for this study, and 10 isodose levels (20% to 105%) were used to evaluate the errors in various dose levels. Results: The prescription dose for all patients was 70 Gy. The mean DDE for CT-to-CBCT deformation was 1.0 Gy (range: 0.3–2.0 Gy) and this was increased to 4.3 Gy (range: 1.5–6.4 Gy) for CBCT-to-CT deformation. The mean increase in DDE between the two deformations was 3.3 Gy (range: 1.0–5.4 Gy). Conclusion: The proposed DDF was used to quantitatively estimate dose deformation errors caused by different pathways to perform DIR. Deforming dose using CBCT-to-CT deformation produced greater error than CT-to-CBCT deformation.« less

Annealing of (DU-10Mo)-Zr Co-Rolled Foils

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pacheco, Robin Montoya; Alexander, David John; Mccabe, Rodney James

2017-01-20

Producing uranium-10wt% molybdenum (DU-10Mo) foils to clad with Al first requires initial bonding of the DU-10Mo foil to zirconium (Zr) by hot rolling, followed by cold rolling to final thickness. Rolling often produces wavy (DU-10Mo)-Zr foils that should be flattened before further processing, as any distortions could affect the final alignment and bonding of the Al cladding to the Zr co-rolled surface layer; this bonding is achieved by a hot isostatic pressing (HIP) process. Distortions in the (DU-10Mo)-Zr foil may cause the fuel foil to press against the Al cladding and thus create thinner or thicker areas in the Almore » cladding layer during the HIP cycle. Post machining is difficult and risky at this stage in the process since there is a chance of hitting the DU-10Mo. Therefore, it is very important to establish a process to flatten and remove any waviness. This study was conducted to determine if a simple annealing treatment could flatten wavy foils. Using the same starting material (i.e. DU-10Mo coupons of the same thickness), five different levels of hot rolling and cold rolling, combined with five different annealing treatments, were performed to determine the effect of these processing variables on flatness, bonding of layers, annealing response, microstructure, and hardness. The same final thickness was reached in all cases. Micrographs, textures, and hardness measurements were obtained for the various processing combinations. Based on these results, it was concluded that annealing at 650°C or higher is an effective treatment to appreciably reduce foil waviness.« less

An alternative for cost-effective remediation of depleted uranium (DU) at certain environmental restoration sites.

PubMed

Miller, M; Galloway, B; VanDerpoel, G; Johnson, E; Copland, J; Salazar, M

2000-02-01

Numerous sites in the United States and around the world are contaminated with depleted uranium (DU) in various forms. A prevalent form is fragmented DU originating from various scientific tests involving high explosives and DU during weapon development programs, at firing practice ranges, or war theaters where DU was used in armor-piercing projectiles. The contamination at these sites is typically very heterogeneous, with discreet, visually identifiable DU fragments mixed with native soil. That is, the bulk-averaged DU activity is quite low, while specific DU fragments, which are distinct from the soil matrix, have much higher specific activity. DU is best known as a dark, black metal that is nearly twice as dense as lead, but DU in the environment readily weathers (oxidizes) to a distinctive bright yellow color that is readily visible. While the specific activity (amount of radioactivity per mass of soil) of DU is relatively low and presents only a minor radiological hazard, the fact that it is radioactive and visually identifiable makes it desirable to remove the DU "contamination" from the environment. The typical approach to conducting this DU remediation is to use radiation detection instruments to identify the contaminant and separate it from the adjacent soil, packaging it for disposal as radioactive waste. This process can be performed manually or by specialized, automated equipment. Alternatively, in certain situations a more cost-effective approach might be simple mechanical or gravimetric separation of the DU fragments from the host soil matrix. At SNL/NM, both the automated and simple mechanical approaches have recently been employed. This paper discusses the pros/cons of the two approaches.

W.E.B. DuBois and the Concepts of Race and Class.

ERIC Educational Resources Information Center

Green, Dan S.; Smith, Earl

1983-01-01

Summarizes and analyzes W.E.B. DuBois's publications on race and class, particularly as he observed the relationships between White and Black Americans from about 1890 to the 1960s. Contends that DuBois's work has been seriously underrated and cites William J. Wilson's work as corroborating and extending DuBois's theories. (CJM)

Sustainable growth, the DuPont way.

PubMed

Holliday, C

2001-09-01

Like many manufacturers, DuPont traditionally has grown by making more and more "stuff." And its business growth has been proportional to the amount of raw materials and energy used--as well as the resulting waste and emissions from operations. Over the years, though, DuPont became aware that cheap supplies of nonrenewable resources wouldn't be endlessly available and that the earth's ecosystems couldn't indefinitely absorb the waste and emissions of production and consumption. Chad Holliday, chairman and CEO of DuPont, believes strongly in the challenge of sustainable growth and makes the business case for it: By using creativity and scientific knowledge effectively, he says, companies can provide strong returns for shareholders and grow their businesses--while also meeting the human needs of societies around the world and reducing the environmental footprint of their operations and products. In fact, a focus on sustainability can help identify new products, markets, partnerships, and intellectual property and lead to substantial business growth. Holliday describes how DuPont developed a three-pronged strategy to translate the concept of sustainability into nuts-and-bolts business practices. Focusing on integrated science, knowledge intensity, and productivity improvement, the strategy was accompanied by a new way to measure progress quantitatively. Sustainable growth should be viewed not as a program for stepped-up environmental performance but as a comprehensive way of doing business, one that delivers tremendous economic value and opens up new opportunities. Ultimately, companies will find that they can generate substantial business value through sustainability while both enhancing the quality of life around the world and protecting the environment.

Lambeaux autofermants pour le traitement des brulures electriques du scalp par haut voltage

PubMed Central

Hafidi, J.; El Mazouz, S.; El Mejatti, H.; Fejjal, N.; Gharib, N.E.; Abbassi, A.; Belmahi, A.M.

2011-01-01

Summary Les brûlures électriques par haut voltage sont responsables de gros dégâts tissulaires en immédiat et dans les jours suivant l’accident du fait de la chaleur importante dégagée par effet joule et de la thrombose microvasculaire évolutive. Les pertes de substances du scalp secondaires à ces brûlures nécessitent une couverture par lambeaux vu la destruction du périoste et du calvarium en regard. De juin 1997 à juin 2008, 15 patients ont été traités pour des pertes de substance du scalp secondaires à des brûlures électriques par haut voltage de diamètre allant de 8 à 11 cm et siégeant dans la région tonsurale. Ces patients ont été opérés dans la première semaine suivant l’accident. Les pertes de substance du scalp de taille moyenne secondaires à ces brûlures peuvent être couvertes per primam de façon fiable par des lambeaux locaux axialisés et multiples. Nous relatons l’expérience du Service de Chirurgie Plastique du Centre Hospitalier Universitaire Ibn-Sina, Rabat, Maroc, dans la gestion et la prise en charge de ces brûlures. PMID:22262963

Jordanian deformation of SL(2) as a contraction of its Drinfeld-Jimbo deformation

NASA Astrophysics Data System (ADS)

Aghamohammadi, A.; Khorrami, M.; Shariati, A.

1995-04-01

We show that $h$-deformation can be obtained, by a singular limit of a similarity transformation, from $q$-deformation; to be specefic, we obtain $\\GL_h(2)$, its differential structure, its inhomogenous extension, and $\\Uh{\\sl(2)}$ from their $q$-deformed counterparts.

Survie au cancer du sein à Rabat (Maroc) 2005-2008

PubMed Central

Mechita, Nada Bennani; Tazi, Mohammed Adnane; Er-Raki, Abdelouahed; Mrabet, Mustapha; Saadi, Asma; Benjaafar, Noureddine; Razine, Rachid

2016-01-01

Introduction Le cancer du sein représente un problème de santé publique au Maroc. L’objectif de ce travail était d’estimer le taux de survie au cancer du sein chez les patientes habitant la ville de Rabat. Méthodes Etude pronostique réalisée chez les patientes diagnostiquées pour cancer du sein de 2005 à 2008, habitant la ville de Rabat et enregistrées au registre des cancers de Rabat. La date d’inclusion dans l’étude correspondait à la date de confirmation histologique du cancer. L’estimation de la survie a été réalisée par la méthode de Kaplan Meier, et la comparaison entre les différentes classes d’une variable a été réalisée par le test de log rank. L’étude des facteurs associés à la survie a été effectuée par le modèle de Cox. Résultats Durant la période d’étude 628 cas de cancer du sein ont été collectés. Le pourcentage de décès était de 19,9%. La survie globale à un an était de 97,1%, elle était de 89,2% à 3 ans et de 80,6 % à 5 ans. En analyse multivariée la survie au cancer du sein était statistiquement moins bonne chez les patientes âgées de plus de 70 ans (p<0,001), ayantune grande taille de tumeur (p<0,001), un stade avancé d’adénopathies (p=0,007), présentant des métastases (p<0,001) et non traitées par hormonothérapie (p=0,002). Conclusion Une grande taille de la tumeur et la présence de métastases sont des facteurs de mauvais pronostic du cancer du sein d’où la nécessité de renforcer les programmes de dépistage. PMID:28292106

Deformations of superconformal theories

DOE PAGES

Córdova, Clay; Dumitrescu, Thomas T.; Intriligator, Kenneth

2016-11-22

Here, we classify possible supersymmetry-preserving relevant, marginal, and irrelevant deformations of unitary superconformal theories in d ≥ 3 dimensions. Our method only relies on symmetries and unitarity. Hence, the results are model independent and do not require a Lagrangian description. Two unifying themes emerge: first, many theories admit deformations that reside in multiplets together with conserved currents. Such deformations can lead to modifications of the supersymmetry algebra by central and noncentral charges. Second, many theories with a sufficient amount of supersymmetry do not admit relevant or marginal deformations, and some admit neither. The classification is complicated by the fact thatmore » short superconformal multiplets display a rich variety of sporadic phenomena, including supersymmetric deformations that reside in the middle of a multiplet. We illustrate our results with examples in diverse dimensions. In particular, we explain how the classification of irrelevant supersymmetric deformations can be used to derive known and new constraints on moduli-space effective actions.« less

DU Processing Efficiency and Reclamation: Plasma Arc Melting

DOE Office of Scientific and Technical Information (OSTI.GOV)

Imhoff, Seth D.; Aikin, Jr., Robert M.; Swenson, Hunter

The work described here corresponds to one piece of a larger effort to increase material usage efficiency during DU processing operations. In order to achieve this goal, multiple technologies and approaches are being tested. These technologies occupy a spectrum of technology readiness levels (TRLs). Plasma arc melting (PAM) is one of the technologies being investigated. PAM utilizes a high temperature plasma to melt materials. Depending on process conditions, there are potential opportunities for recycling and material reclamation. When last routinely operational, the LANL research PAM showed extremely promising results for recycling and reclamation of DU and DU alloys. The currentmore » TRL is lower due to machine idleness for nearly two decades, which has proved difficult to restart. This report describes the existing results, promising techniques, and the process of bringing this technology back to readiness at LANL.« less

Advantages of formulating an evolution equation directly for elastic distortional deformation in finite deformation plasticity

NASA Astrophysics Data System (ADS)

Rubin, M. B.; Cardiff, P.

2017-11-01

Simo (Comput Methods Appl Mech Eng 66:199-219, 1988) proposed an evolution equation for elastic deformation together with a constitutive equation for inelastic deformation rate in plasticity. The numerical algorithm (Simo in Comput Methods Appl Mech Eng 68:1-31, 1988) for determining elastic distortional deformation was simple. However, the proposed inelastic deformation rate caused plastic compaction. The corrected formulation (Simo in Comput Methods Appl Mech Eng 99:61-112, 1992) preserves isochoric plasticity but the numerical integration algorithm is complicated and needs special methods for calculation of the exponential map of a tensor. Alternatively, an evolution equation for elastic distortional deformation can be proposed directly with a simplified constitutive equation for inelastic distortional deformation rate. This has the advantage that the physics of inelastic distortional deformation is separated from that of dilatation. The example of finite deformation J2 plasticity with linear isotropic hardening is used to demonstrate the simplicity of the numerical algorithm.

Deformations in VLBI antennas

NASA Technical Reports Server (NTRS)

Clark, T. A.; Thomsen, P.

1988-01-01

A study is presented of deformations in antennas with the emphasis on their influence on VLBI measurements. The GIFTS structural analysis program has been used to model the VLBI antenna in Fairbanks (Alaska). The report identifies key deformations and studies the effect of gravity, wind, and temperature. Estimates of expected deformations are given.

Experimental deformation of a mafic rock - interplay between fracturing, reaction and viscous deformation

NASA Astrophysics Data System (ADS)

Marti, Sina; Stünitz, Holger; Heilbronner, Renée; Plümper, Oliver; Drury, Martyn

2016-04-01

Deformation experiments were performed on natural Maryland Diabase (˜ 55% Plg, 42% Px, 3% accessories, 0.18 wt.-% H2O added) in a Griggs-type deformation apparatus in order to explore the brittle-viscous transition and the interplay between deformation and mineral reactions. Shear experiments at strain rates of ˜ 2e-5 /s are performed, at T=600, 700 and 800°C and confining pressures Pc=1.0 and 1.5 GPa. Deformation localizes in all experiments. Below 700°C, the microstructure is dominated by brittle deformation with a foliation formed by cataclastic flow and high strain accommodated along 3-5 major ultracataclasite shear bands. At 700°C, the bulk of the material still exhibits abundant microfractures, however, deformation localizes into an anastomosing network of shear bands (SB) formed from a fine-grained (<< 1 μm) mixture of newly formed Plg and Amph. These reaction products occur almost exclusively along syn-kinematic structures such as fractures and SB. Experiments at 800°C show extensive mineral reactions, with the main reaction products Amph+Plg (+Zo). Deformation is localized in broad C' and C SB formed by a fine-grained (0.1 - 0.8 μm) mixture of Plg+Amph (+Zo). The onset of mineral reactions in the 700°C experiments shows that reaction kinetics and diffusional mass transport are fast enough to keep up with the short experimental timescales. While in the 700°C experiments brittle processes kinematically contribute to deformation, fracturing is largely absent at 800°C. Diffusive mass transfer dominates. The very small grain size within SB favours a grain size sensitive deformation mechanism. Due to the presence of water (and relatively high supported stresses), dissolution-precipitation creep is interpreted to be the dominant strain accommodating mechanism. From the change of Amph coronas around Px clasts with strain, we can determine that Amph is re-dissolved at high stress sites while growing in low stress sites, showing the ability of Amph to

Deformation of second and third quantization

NASA Astrophysics Data System (ADS)

Faizal, Mir

2015-03-01

In this paper, we will deform the second and third quantized theories by deforming the canonical commutation relations in such a way that they become consistent with the generalized uncertainty principle. Thus, we will first deform the second quantized commutator and obtain a deformed version of the Wheeler-DeWitt equation. Then we will further deform the third quantized theory by deforming the third quantized canonical commutation relation. This way we will obtain a deformed version of the third quantized theory for the multiverse.

Cancer du sein bilatéral synchrone au Maroc: caractéristiques épidémiologiques et cliniques

PubMed Central

Boufettal, Houssine; Samouh, Naïma

2015-01-01

Préciser la fréquence, les facteurs de risque et le pronostic du cancer du sein bilatéral, à partir d'une étude rétrospective de 22 cas de cancer du sein bilatéral synchrone dans un pays du Maghreb. De 2002 à 2010, 625 patientes étaient prises en charge pour cancer du sein au service de Gynécologie-Obstétrique «C» du centre hospitalier universitaire de Casablanca. 22 cas de cancer bilatéral synchrone étaient diagnostiqués. Nos résultats sont comparés avec ceux de la littérature. La fréquence de la bilatéralité du cancer du sein synchrone était de 3,52% (22/625). L'intervalle de temps moyen entre les deux cancers est de 4 mois (0 à 6 mois). Les patientes âgées de moins de 40 ans lors du premier cancer avaient six fois plus de risque de développer un cancer au niveau du sein controlatéral que les femmes âgées de plus de 40 ans. Les patientes atteintes d'une tumeur T3 ou T4 avaient un risque neuf fois plus élevé que les autres. 90,9% (2/22) des cas des premiers cancers sont des adénocarcinomes infiltrants. Les types histologiques du premier et du douzième cancer étaient identiques dans 86,4% (19/22) des cas. Quant au pronostic, il dépend à la fois du stade du premier et du deuxième cancer et le traitement de ce dernier doit obéir aux mêmes règles du traitement du premier cancer. L'incidence du cancer bilatéral synchrone du sein est de 3,52% dans notre série. Le cancer du sein unilatéral constitue un facteur de risque de développement d'un cancer du sein controlatéral. Une surveillance à vie est nécessaire au cours d'un cancer du sein pour détecter un cancer controlatéral. PMID:26090066

Deformations of the Almheiri-Polchinski model

NASA Astrophysics Data System (ADS)

Kyono, Hideki; Okumura, Suguru; Yoshida, Kentaroh

2017-03-01

We study deformations of the Almheiri-Polchinski (AP) model by employing the Yang-Baxter deformation technique. The general deformed AdS2 metric becomes a solution of a deformed AP model. In particular, the dilaton potential is deformed from a simple quadratic form to a hyperbolic function-type potential similarly to integrable deformations. A specific solution is a deformed black hole solution. Because the deformation makes the spacetime structure around the boundary change drastically and a new naked singularity appears, the holographic interpretation is far from trivial. The Hawking temperature is the same as the undeformed case but the Bekenstein-Hawking entropy is modified due to the deformation. This entropy can also be reproduced by evaluating the renormalized stress tensor with an appropriate counter-term on the regularized screen close to the singularity.

Les inconvénients de perdre du poids

PubMed Central

Bosomworth, N. John

2012-01-01

Résumé Objectif Explorer les raisons pour lesquelles la perte de poids à long terme échoue la plupart du temps et évaluer les conséquences de diverses trajectoires pondérales, y compris la stabilité, la perte et le gain. Source des données Les études qui évaluent les paramètres pondéraux dans la population sont en majorité observationnelles. Des données probantes de niveau I ont été publiées pour évaluer l’influence des interventions relatives au poids sur la mortalité et la qualité de vie. Message principal Seulement un petit pourcentage des personnes qui désirent perdre du poids réussissent à le faire de manière durable. La mortalité est la plus faible chez les personnes se situant dans la catégorie de poids élevé-normal et surpoids. La trajectoire pondérale la plus sécuritaire est la stabilité du poids avec une optimisation de la condition physique et métabolique. Il est démontré que la mortalité est plus faible chez les personnes ayant des comorbidités reliées à l’obésité si elles perdent du poids. Il est aussi établi que la qualité de vie sur le plan de la santé est meilleure chez les personnes obèses qui perdent du poids. Par contre, la perte de poids chez une personne obèse autrement en santé est associée à une mortalité accrue. Conclusion La perte de poids est recommandable seulement chez les personnes qui ont des comorbidités reliées à l’obésité. Les personnes obèses en santé qui veulent perdre du poids devraient être informées qu’il peut y avoir des risques à le faire. Une stratégie qui se traduit par un indice de masse corporelle stable avec une condition physique et métabolique optimisée, peu importe le poids, est l’option d’intervention la plus sécuritaire en ce qui concerne le poids.

Dépistage précoce des retards du développement moteur

PubMed Central

Harris, Susan R.

2016-01-01

Résumé Objectif Décrire le test HINT (Harris Infant Neuromotor Test), un test d’évaluation du développement neuromoteur chez les nourrissons publié en 2010, qui s’appuie sur les normes canadiennes et peut être utilisé pour dépister les retards du développement moteur durant la première année de la vie. Qualité des données D’abondantes recherches ont été publiées sur la fiabilité intra-évaluateur, inter-évaluateur et test-retest ainsi que sur la validité convergente, prédictive, du contenu et des groupes connus du test HINT, de même que sur la sensibilité, la spécificité et les valeurs prédictives négatives et positives des inquiétudes des parents, telles qu’évaluées par le test HINT. La plupart des données probantes sont de niveau II. Message principal Il est important de diagnostiquer les retards du développement moteur durant la première année de vie, car ils sont souvent le signe de retards du développement généralisés ou de déficiences précises, telles que la paralysie cérébrale. Les inquiétudes des parents quant au développement moteur de leur enfant sont une valeur prédictive robuste de diagnostics subséquents de retard du développement moteur. Conclusion Seul le dépistage précoce des retards du développement moteur, initialement par l’entremise d’outils de dépistage comme le test HINT, permet de recommander le patient à une intervention précoce qui profiterait tant à l’enfant qu’à sa famille. PMID:27521405

Hazardous Waste Cleanup: DuPont Imaging Department in Parlin, New Jersey

EPA Pesticide Factsheets

DuPont has owned and operated a chemical manufacturing plant on Cheesequake Road in Parlin, New Jersey, since 1904. DuPont manufactured a variety of products at the plant including, photographic films, automotive paints, pigments, adhesives, thinners,

SU-E-J-104: Evaluation of Accuracy for Various Deformable Image Registrations with Virtual Deformation QA Software

DOE Office of Scientific and Technical Information (OSTI.GOV)

Han, S; Kim, K; Kim, M

Purpose: The accuracy of deformable image registration (DIR) has a significant dosimetric impact in radiation treatment planning. We evaluated accuracy of various DIR algorithms using virtual deformation QA software (ImSimQA, Oncology System Limited, UK). Methods: The reference image (Iref) and volume (Vref) was first generated with IMSIMQA software. We deformed Iref with axial movement of deformation point and Vref depending on the type of deformation that are the deformation1 is to increase the Vref (relaxation) and the deformation 2 is to decrease the Vref (contraction) .The deformed image (Idef) and volume (Vdef) were inversely deformed to Iref and Vref usingmore » DIR algorithms. As a Result, we acquired deformed image (Iid) and volume (Vid). The DIR algorithms were optical flow (HS, IOF) and demons (MD, FD) of the DIRART. The image similarity evaluation between Iref and Iid was calculated by Normalized Mutual Information (NMI) and Normalized Cross Correlation (NCC). The value of Dice Similarity Coefficient (DSC) was used for evaluation of volume similarity. Results: When moving distance of deformation point was 4 mm, the value of NMI was above 1.81 and NCC was above 0.99 in all DIR algorithms. Since the degree of deformation was increased, the degree of image similarity was decreased. When the Vref increased or decreased about 12%, the difference between Vref and Vid was within ±5% regardless of the type of deformation. The value of DSC was above 0.95 in deformation1 except for the MD algorithm. In case of deformation 2, that of DSC was above 0.95 in all DIR algorithms. Conclusion: The Idef and Vdef have not been completely restored to Iref and Vref and the accuracy of DIR algorithms was different depending on the degree of deformation. Hence, the performance of DIR algorithms should be verified for the desired applications.« less

Deformation Invariant Attribute Vector for Deformable Registration of Longitudinal Brain MR Images

PubMed Central

Li, Gang; Guo, Lei; Liu, Tianming

2009-01-01

This paper presents a novel approach to define deformation invariant attribute vector (DIAV) for each voxel in 3D brain image for the purpose of anatomic correspondence detection. The DIAV method is validated by using synthesized deformation in 3D brain MRI images. Both theoretic analysis and experimental studies demonstrate that the proposed DIAV is invariant to general nonlinear deformation. Moreover, our experimental results show that the DIAV is able to capture rich anatomic information around the voxels and exhibit strong discriminative ability. The DIAV has been integrated into a deformable registration algorithm for longitudinal brain MR images, and the results on both simulated and real brain images are provided to demonstrate the good performance of the proposed registration algorithm based on matching of DIAVs. PMID:19369031

Nearly associative deformation quantization

NASA Astrophysics Data System (ADS)

Vassilevich, Dmitri; Oliveira, Fernando Martins Costa

2018-04-01

We study several classes of non-associative algebras as possible candidates for deformation quantization in the direction of a Poisson bracket that does not satisfy Jacobi identities. We show that in fact alternative deformation quantization algebras require the Jacobi identities on the Poisson bracket and, under very general assumptions, are associative. At the same time, flexible deformation quantization algebras exist for any Poisson bracket.

Project REPONS: Offshore Faults, Tectonic Deformation and Turbidite Record in Response to the January 12 2010 Earthquake, Haiti

NASA Astrophysics Data System (ADS)

McHugh, C. M.; Gulick, S. P.; Cormier, M.; Dieudonne, N.; Diebold, J. B.; Douilly, R.; Hornbach, M.; Johnson, H. E.; Mishkin, K.; Seeber, L.; Sorlien, C. C.; Steckler, M. S.; Symithe, S. J.

2010-12-01

As part of an NSF RAPID response to the January 12, 2010 earthquake, we mapped the underwater continuation of the Enriquillo-Plantain Garden fault zone (EPGF) west of Léogâne. Multibeam bathymetry, sidescan sonar, chirp subbottom profiler, sediment sampling and CTD measurements were conducted in water depths of 2 m to 1750 m from the R/V Endeavor and from a small inflatable boat. The offshore segment of the EPGF is manifested by two steep, 50-80 m high linear ridges and at least two subsurface faults. The submarine EPGF is part of a transition from releasing to restraining segment. To the east, it joins its onshore trace in a releasing bend and continues to the west in a restraining bend that perhaps caused the Tapion ridge. Within the Baies de Petit and Grand Goâve, river outlets are correlated with lateral spreading and/or subsidence where we observed increased local damage to structures. Lateral spreading and/or subsidence appears to have increased tsunami effects locally. Coral uplift NE and SW of offshore fault traces offer evidence of the January 12, 2010 surface deformation. While a seafloor rupture is not evident from the data collected we do image deformation within the upper 20 m in both bays. Mass wasting and gravity flow deposits from the last and older earthquakes were tracked from the Léogâne delta and along the coast to the deepest depocenter. Th-234 and Be-7 with half-lives of 24 and 53 days, respectively verified the January 12 turbidite and indicated an influx of terrigenous sediment mixed with marine sources. Coral debris was sampled in the shelf and upper slope (100-300 m) near the EPGF; basalt sand derived from the highlands and wood fragments at intermediate water depths (1000-1100 m); lastly an ~0.03 km3 and >1 m thick turbidite was deposited over 50 km2 in the Canal du Sud depocenter (1750 m). The sandy parts of all cores recovered from Canal du Sud depocenter have alternate episodes of traction deposition and erosion that reflect

Post Deformation at Room and Cryogenic Temperature Cooling Media on Severely Deformed 1050-Aluminum

NASA Astrophysics Data System (ADS)

Khorrami, M. Sarkari; Kazeminezhad, M.

2018-03-01

The annealed 1050-aluminum sheets were initially subjected to the severe plastic deformation through two passes of constrained groove pressing (CGP) process. The obtained specimens were post-deformed by friction stir processing at room and cryogenic temperature cooling media. The microstructure evolutions during mentioned processes in terms of grain structure, misorientation distribution, and grain orientation spread (GOS) were characterized using electron backscattered diffraction. The annealed sample contained a large number of "recrystallized" grains and relatively large fraction (78%) of high-angle grain boundaries (HAGBs). When CGP process was applied on the annealed specimen, the elongated grains with interior substructure were developed, which was responsible for the formation of 80% low-angle grain boundaries. The GOS map of the severely deformed specimen manifested the formation of 43% "distorted" and 51% "substructured" grains. The post deformation of severely deformed aluminum at room temperature led to the increase in the fraction of HAGBs from 20 to 60%. Also, it gave rise to the formation of "recrystallized" grains with the average size of 13 μm, which were coarser than the grains predicted by Zener-Hollomon parameter. This was attributed to the occurrence of appreciable grain growth during post deformation. In the case of post deformation at cryogenic temperature cooling medium, the grain size was decreased, which was in well agreement with the predicted grain size. The cumulative distribution of misorientation was the same for both processing routes. Mechanical properties characterizations in terms of nano-indentation and tensile tests revealed that the post deformation process led to the reduction in hardness, yield stress, and ultimate tensile strength of the severely deformed aluminum.

Nuclear Deformation at Finite Temperature

NASA Astrophysics Data System (ADS)

Alhassid, Y.; Gilbreth, C. N.; Bertsch, G. F.

2014-12-01

Deformation, a key concept in our understanding of heavy nuclei, is based on a mean-field description that breaks the rotational invariance of the nuclear many-body Hamiltonian. We present a method to analyze nuclear deformations at finite temperature in a framework that preserves rotational invariance. The auxiliary-field Monte Carlo method is used to generate a statistical ensemble and calculate the probability distribution associated with the quadrupole operator. Applying the technique to nuclei in the rare-earth region, we identify model-independent signatures of deformation and find that deformation effects persist to temperatures higher than the spherical-to-deformed shape phase-transition temperature of mean-field theory.

Cosmetic and Functional Nasal Deformities

MedlinePlus

... nasal complaints. Nasal deformity can be categorized as “cosmetic” or “functional.” Cosmetic deformity of the nose results in a less ... taste , nose bleeds and/or recurrent sinusitis . A cosmetic or functional nasal deformity may occur secondary to ...

Hazardous Waste Cleanup: E.I. DuPont de Nemours & Company in Pompton Lakes, New Jersey

EPA Pesticide Factsheets

E.I. DuPont De Nemours & Company is located at 2000 Cannonball Road, Pompton Lakes, New Jersey. The DuPont Pompton Lakes Works site (DuPont) occupies approximately 570 acres of land in Pompton Lakes and Wanaque.

Localisation inhabituelle de la tuberculose: ostéoarthrite tuberculose du pouce

PubMed Central

Mortaji, Aziz; Koulali, Khalid; Galuia, Farid

2014-01-01

L'ostéoarthrite tuberculose est rare au niveau des doigts. Nous rapportons une observation d'atteinte du pouce chez un patient de 55 ans. Il avait présenté une tuméfaction douloureuse du pouce droit suite à un traumatisme du pouce. L’étude bactériologique et une biopsie avaient permis de confirmer le diagnostic. Un traitement antibacillaire de 12 mois avait donné des résultats satisfaisants. Les particularités de la prise en charge sont discutées par rapport aux données de la littérature. PMID:25932075

Etude thermo-hydraulique de l'ecoulement du moderateur dans le reacteur CANDU-6

NASA Astrophysics Data System (ADS)

Mehdi Zadeh, Foad

Etant donne la taille (6,0 m x 7,6 m) ainsi que le domaine multiplement connexe qui caracterisent la cuve des reacteurs CANDU-6 (380 canaux dans la cuve), la physique qui gouverne le comportement du fluide moderateur est encore mal connue de nos jours. L'echantillonnage de donnees dans un reacteur en fonction necessite d'apporter des changements a la configuration de la cuve du reacteur afin d'y inserer des sondes. De plus, la presence d'une zone intense de radiations empeche l'utilisation des capteurs courants d'echantillonnage. En consequence, l'ecoulement du moderateur doit necessairement etre etudie a l'aide d'un modele experimental ou d'un modele numerique. Pour ce qui est du modele experimental, la fabrication et la mise en fonction de telles installations coutent tres cher. De plus, les parametres de la mise a l'echelle du systeme pour fabriquer un modele experimental a l'echelle reduite sont en contradiction. En consequence, la modelisation numerique reste une alternative importante. Actuellement, l'industrie nucleaire utilise une approche numerique, dite de milieu poreux, qui approxime le domaine par un milieu continu ou le reseau des tubes est remplace par des resistances hydrauliques distribuees. Ce modele est capable de decrire les phenomenes macroscopiques de l'ecoulement, mais ne tient pas compte des effets locaux ayant un impact sur l'ecoulement global, tel que les distributions de temperatures et de vitesses a proximite des tubes ainsi que des instabilites hydrodynamiques. Dans le contexte de la surete nucleaire, on s'interesse aux effets locaux autour des tubes de calandre. En effet, des simulations faites par cette approche predisent que l'ecoulement peut prendre plusieurs configurations hydrodynamiques dont, pour certaines, l'ecoulement montre un comportement asymetrique au sein de la cuve. Ceci peut provoquer une ebullition du moderateur sur la paroi des canaux. Dans de telles conditions, le coefficient de reactivite peut varier de maniere

Deformation of crowns during cementation.

PubMed

Wilson, P R; Goodkind, R J; Delong, R; Sakaguchi, R

1990-11-01

Deformation of crowns during cementation was investigated by a simple loading system of defined crowns with silicone fluids as cements. Deformation of the crowns was measured by long stain gauges that encircled the cervical margins. Die spacing was simulated by etching the die. Venting was simulated by removing a small screw. Deformation of the crowns was decreased by decreasing the viscosity of fluid, increasing the thickness of the crowns, and venting. Etching the die decreased the seating times of the crowns, but did not alter the level of deformation. Terminal cementation with zinc phosphate cement confirmed the presence of crown deformation during cementation. The results have consequences for bonded and all-ceramic crowns, and explain several clinical phenomena. It is suggested that low viscosity cements, low seating forces, and die spacing be used to decrease the deformation of crowns during seating. The importance of passive fitting of the crown to the tooth is stressed.

Dealing with difficult deformations: construction of a knowledge-based deformation atlas

NASA Astrophysics Data System (ADS)

Thorup, S. S.; Darvann, T. A.; Hermann, N. V.; Larsen, P.; Ólafsdóttir, H.; Paulsen, R. R.; Kane, A. A.; Govier, D.; Lo, L.-J.; Kreiborg, S.; Larsen, R.

2010-03-01

Twenty-three Taiwanese infants with unilateral cleft lip and palate (UCLP) were CT-scanned before lip repair at the age of 3 months, and again after lip repair at the age of 12 months. In order to evaluate the surgical result, detailed point correspondence between pre- and post-surgical images was needed. We have previously demonstrated that non-rigid registration using B-splines is able to provide automated determination of point correspondences in populations of infants without cleft lip. However, this type of registration fails when applied to the task of determining the complex deformation from before to after lip closure in infants with UCLP. The purpose of the present work was to show that use of prior information about typical deformations due to lip closure, through the construction of a knowledge-based atlas of deformations, could overcome the problem. Initially, mean volumes (atlases) for the pre- and post-surgical populations, respectively, were automatically constructed by non-rigid registration. An expert placed corresponding landmarks in the cleft area in the two atlases; this provided prior information used to build a knowledge-based deformation atlas. We model the change from pre- to post-surgery using thin-plate spline warping. The registration results are convincing and represent a first move towards an automatic registration method for dealing with difficult deformations due to this type of surgery.

Foldover-free shape deformation for biomedicine.

PubMed

Yu, Hongchuan; Zhang, Jian J; Lee, Tong-Yee

2014-04-01

Shape deformation as a fundamental geometric operation underpins a wide range of applications, from geometric modelling, medical imaging to biomechanics. In medical imaging, for example, to quantify the difference between two corresponding images, 2D or 3D, one needs to find the deformation between both images. However, such deformations, particularly deforming complex volume datasets, are prone to the problem of foldover, i.e. during deformation, the required property of one-to-one mapping no longer holds for some points. Despite numerous research efforts, the construction of a mathematically robust foldover-free solution subject to positional constraints remains open. In this paper, we address this challenge by developing a radial basis function-based deformation method. In particular we formulate an effective iterative mechanism which ensures the foldover-free property is satisfied all the time. The experimental results suggest that the resulting deformations meet the internal positional constraints. In addition to radial basis functions, this iterative mechanism can also be incorporated into other deformation approaches, e.g. B-spline based FFDs, to develop different deformable approaches for various applications. Crown Copyright © 2013. Published by Elsevier Inc. All rights reserved.

Le schwannome malin du nerf grand sciatique chez l'enfant

PubMed Central

Lechqar, Maryem; Elbiache, Imad; Atarraf, Karima; Bouabdellah, Youssef; Afifi, My Abderahman

2012-01-01

Le schwannome malin est une tumeur très rare chez l'enfant (1 à 2% des tumeurs des tissus mous), elle se développe au dépend des cellules de schwanne. Dans ce travail, les auteurs rapportent un cas de schwannome malin développé au dépend du nerf grand sciatique. La radiographie de la cuisse de face et de profil était normale. L'imagerie par résonance magnétique a identifié une lésion le long du trajet du nerf grand sciatique. La tumeur a été réséquée en totalité emportant le nerf grand sciatique. L'examen anatomo-pathologique a confirmé le diagnostic. PMID:23133710

Management of Congenital Chest Wall Deformities

PubMed Central

Blanco, Felix C.; Elliott, Steven T.; Sandler, Anthony D.

2011-01-01

Congenital chest wall deformities are considered to be anomalies in chest wall growth. These can be categorized as either rib cage overgrowth or deformities related to inadequate growth (aplasia or dysplasia). Rib cage overgrowth leads to depression of the sternum (pectus excavatum) or protuberance of the sternum (pectus carinatum) and accounts for greater than 90% of congenital chest wall deformities. The remaining deformities are a result of inadequate growth. Evolution in the management of congenital chest wall deformities has made significant progress over the past 25 years. This article will review chest wall deformities and the current management strategies of these interesting anomalies. PMID:22294949

Interfacial Bubble Deformations

NASA Astrophysics Data System (ADS)

Seymour, Brian; Shabane, Parvis; Cypull, Olivia; Cheng, Shengfeng; Feitosa, Klebert

Soap bubbles floating at an air-water experience deformations as a result of surface tension and hydrostatic forces. In this experiment, we investigate the nature of such deformations by taking cross-sectional images of bubbles of different volumes. The results show that as their volume increases, bubbles transition from spherical to hemispherical shape. The deformation of the interface also changes with bubble volume with the capillary rise converging to the capillary length as volume increases. The profile of the top and bottom of the bubble and the capillary rise are completely determined by the volume and pressure differences. James Madison University Department of Physics and Astronomy, 4VA Consortium, Research Corporation for Advancement of Science.

Deformation-induced crystallographic-preferred orientation of hcp-iron: An experimental study using a deformation-DIA apparatus

NASA Astrophysics Data System (ADS)

Nishihara, Yu; Ohuchi, Tomohiro; Kawazoe, Takaaki; Seto, Yusuke; Maruyama, Genta; Higo, Yuji; Funakoshi, Ken-ichi; Tange, Yoshinori; Irifune, Tetsuo

2018-05-01

Shear and uniaxial deformation experiments on hexagonal close-packed iron (hcp-Fe) was conducted using a deformation-DIA apparatus at a pressure of 13-17 GPa and a temperature of 723 K to determine its deformation-induced crystallographic-preferred orientation (CPO). Development of the CPO in the deforming sample is determined in-situ based on two-dimensional X-ray diffraction using monochromatic synchrotron X-rays. In the shear deformation geometry, the <0001> and < 11 2 bar 0 > axes gradually align to be sub-parallel to the shear plane normal and shear direction, respectively, from the initial random texture. In the uniaxial compression and tensile geometry, the <0001> and < 11 2 bar 0 > axes, respectively, gradually align along the direction of the uniaxial deformation axis. These results suggest that basal slip (0001) < 11 2 bar 0 > is the dominant slip system in hcp-Fe under the studied deformation conditions. The P-wave anisotropy for a shear deformed sample was calculated using elastic constants at the inner core condition by recent ab-initio calculations. Strength of the calculated anisotropy was comparable to or higher than axisymmetric anisotropy in Earth's inner core.

Late-Paleozoic-Mesozoic deformational and deformation related metamorphic structures of Kuznetsk-Altai region

NASA Astrophysics Data System (ADS)

Zinoviev, Sergei

2014-05-01

Kuznetsk-Altai region is a part of the Central Asian Orogenic Belt. The nature and formation mechanisms of the observed structure of Kuznetsk-Altai region are interpreted by the author as the consequence of convergence of Tuva-Mongolian and Junggar lithospheric block structures and energy of collision interaction between the blocks of crust in Late-Paleozoic-Mesozoic period. Tectonic zoning of Kuznetsk-Altai region is based on the principle of adequate description of geological medium (without methods of 'primary' state recovery). The initial indication of this convergence is the crust thickening in the zone of collision. On the surface the mechanisms of lateral compression form a regional elevation; with this elevation growth the 'mountain roots' start growing. With an approach of blocks an interblock elevation is divided into various fragments, and these fragments interact in the manner of collision. The physical expression of collision mechanisms are periodic pulses of seismic activity. The main tectonic consequence of the block convergence and collision of interblock units is formation of an ensemble of regional structures of the deformation type on the basis of previous 'pre-collision' geological substratum [Chikov et al., 2012]. This ensemble includes: 1) allochthonous and autochthonous blocks of weakly deformed substratum; 2) folded (folded-thrust) systems; 3) dynamic metamorphism zones of regional shears and main faults. Characteristic of the main structures includes: the position of sedimentary, magmatic and PT-metamorphic rocks, the degree of rock dynamometamorphism and variety rock body deformation, as well as the styles and concentrations of mechanic deformations. 1) block terranes have weakly elongated or isometric shape in plane, and they are the systems of block structures of pre-collision substratum separated by the younger zones of interblock deformations. They stand out among the main deformation systems, and the smallest are included into the

Les accidents du travail dans le transport urbain en commun de la ville province de Kinshasa, République Démocratique du Congo: une étude transversale descriptive

PubMed Central

Wangata, Jemima; Elenge, Myriam; De Brouwer, Christophe

2014-01-01

Introduction Le transport en commun urbain constitue un secteur où les travailleurs sont très exposés aux accidents du travail. Cette étude visait une description épidémiologique des accidents du travail dans le secteur informel du transport en commun à Kinshasa en vue d'apporter les pistes d'amélioration de la sécurité des travailleurs dans cette activité. Méthodes Un questionnaire sur les accidents du travail, administré en Décembre 2012 a permis d'explorer les tendances significatives entre les accidents et leurs circonstances, leurs facteurs associés, leurs conséquences au sein d'une population des travailleurs (n = 472) du transport en commun à Kinshasa. Résultats Durant les 12 derniers précédant l’étude 76.5% des travailleurs ont connu au moins un accident du travail, 54,8% ont connu un arrêt d'au moins 1jour. Les accidents liés à la circulation routière étaient plus important suivis des chutes. Les facteurs ayant montré des différences significatives étaient le travail sous l'influence de l'alcool et le port des équipements de protection individuelle. Les plaies (46,3%) et les contusions (39,4%) étaient les lésions les plus courantes. Les membres supérieurs (51,3%) et inférieurs (30,7%) étaient les plus atteints. 76,6% des travailleurs ont assumé seuls leur prise en charge médicale. Conclusion L'incidence des accidents du travail dans ce secteur est très élevée. La mise en place d'une politique de prévention et gestion de différents facteurs associés ainsi qu'un système de déclaration d'accidents est nécessaire dans ce secteur. Les patrons ainsi que les politiques devraient veiller à une prise en charge médicale correcte pour des travailleurs accidentés. PMID:25667703

Une forme exceptionnelle de la luxation perilunaire du carpe

PubMed Central

Elouakili, Issam; Ouchrif, Younes; Najib, Abdeljaouad; Ouakrim, Redouane; Lamrani, Omar; Kharmaz, Mohammed; Ismael, Farid; Lahlou, Abdo; Elouadghiri, Mohammed; El Bardouni, Ahmed; Mahfoud, Mustapha; Berrada, Mohammed Saleh; El Yaccoubi, Mouradh

2014-01-01

Les luxations périlunaires (LPL) du carpe sont des lésions extrêmement rares, qui peuvent passer inaperçue en raison d'un tableau clinique souvent trompeur, des radiographies en profil non strict ou d'interprétation difficile. Nous rapportons l'observation d'une luxation périlunaire stade III selon la classification de Witvoët et Allieu chez un patient de 32 ans, il s'agit d'une forme encore plus rare voire exceptionnelle et qui peut induire de sérieux problèmes en raison de la sévérité des dommages ligamentaires et du risque de nécrose du semilunaire plus important dans ce type de lésions. Le traitement est toujours chirurgical et doit être réalisé dans les plus brefs délais afin d’éviter les complications. PMID:25404968

Marihuana: A Conversation with NIDA's Robert L. DuPont.

PubMed

Maugh, T H

1976-05-14

Robert L. DuPont, director of the National Institute on Drug Abuse (NIDA), made headlines recently when he became one of the first Administration officials publicly to recommend a liberalization of marihuana laws. The occasion was a press conference accompanying the release of Marihuana and Health, NIDA's fifth annual report to the Congress on marihuana research. Recently, Science talked with DuPont and asked him to elaborate on those views. DuPont, a 40-year-old Harvard M.D., served as Director of the District of Columbia's Narcotics Treatment Administration from 1970 to 1973, where he conducted a comprehensive program for treatment of heroin addiction. In June 1973, Richard Nixon appointed him director of the White House Special Action Office for Drug Abuse Prevention. He held that position until the office was terminated on 30 June 1975. He has been director of NIDA since September 1973.

Niveaux d'étude du cerveau, et sagesse physique

NASA Astrophysics Data System (ADS)

Toulouse, Gérard

1993-02-01

The brain is a complex spatio-temporal affair. Several brain theories propose the definition of three superposed levels of study. But physics, though the experience of condensed matter physics, suggests that it is unwise to enforce onto brain theories a unified hierarchical scheme, the inspiration for which seems to come from the realm of sub-molecular physics. Le cerveau est une affaire spatio-temporelle complexe. Plusieurs théories du cerveau proposent de définir trois niveaux d'études superposés. Mais la physique, à travers l'expérience de la physique de la matière condensée, suggère qu'il n'est pas sage d'imposer sur les théories du cerveau un schéma hiérarchique unifié, dont l'inspiration semble provenir du domaine de la physique sub-moléculaire.

Homogeneous Yang-Baxter deformations as generalized diffeomorphisms

NASA Astrophysics Data System (ADS)

Sakamoto, Jun-ichi; Sakatani, Yuho; Yoshida, Kentaroh

2017-10-01

Yang-Baxter (YB) deformations of string sigma model provide deformed target spaces. We propose that homogeneous YB deformations always lead to a certain class of β-twisted backgrounds and represent the bosonic part of the supergravity fields in terms of the classical r-matrix associated with the YB deformation. We then show that various β-twisted backgrounds can be realized by considering generalized diffeomorphisms in the undeformed background. Our result extends the notable relation between the YB deformations and (non-commuting) TsT transformations. We also discuss more general deformations beyond the YB deformations.

Deformation twinning: Influence of strain rate

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gray, G.T. III

Twins in most crystal structures, including advanced materials such as intermetallics, form more readily as the temperature of deformation is decreased or the rate of deformation is increased. Both parameters lead to the suppression of thermally-activated dislocation processes which can result in stresses high enough to nucleate and grow deformation twins. Under high-strain rate or shock-loading/impact conditions deformation twinning is observed to be promoted even in high stacking fault energy FCC metals and alloys, composites, and ordered intermetallics which normally do not readily deform via twinning. Under such conditions and in particular under the extreme loading rates typical of shockmore » wave deformation the competition between slip and deformation twinning can be examined in detail. In this paper, examples of deformation twinning in the intermetallics TiAl, Ti-48Al-lV and Ni{sub 3}A as well in the cermet Al-B{sub 4}C as a function of strain rate will be presented. Discussion includes: (1) the microstructural and experimental variables influencing twin formation in these systems and twinning topics related to high-strain-rate loading, (2) the high velocity of twin formation, and (3) the influence of deformation twinning on the constitutive response of advanced materials.« less

Polygonal deformation bands in sandstone

NASA Astrophysics Data System (ADS)

Antonellini, Marco; Nella Mollema, Pauline

2017-04-01

We report for the first time the occurrence of polygonal faults in sandstone, which is compelling given that layer-bound polygonal fault systems have been observed so far only in fine-grained sediments such as clay and chalk. The polygonal faults are dm-wide zones of shear deformation bands that developed under shallow burial conditions in the lower portion of the Jurassic Entrada Fm (Utah, USA). The edges of the polygons are 1 to 5 meters long. The shear deformation bands are organized as conjugate faults along each edge of the polygon and form characteristic horst-like structures. The individual deformation bands have slip magnitudes ranging from a few mm to 1.5 cm; the cumulative average slip magnitude in a zone is up to 10 cm. The deformation bands heaves, in aggregate form, accommodate a small isotropic horizontal extension (strain < 0.005). The individual shear deformation bands show abutting T-junctions, veering, curving, and merging where they mechanically interact. Crosscutting relationships are rare. The interactions of the deformation bands are similar to those of mode I opening fractures. Density inversion, that takes place where under-compacted and over-pressurized layers (Carmel Fm) lay below normally compacted sediments (Entrada Sandstone), may be an important process for polygonal deformation bands formation. The gravitational sliding and soft sediment structures typically observed within the Carmel Fm support this hypothesis. Soft sediment deformation may induce polygonal faulting in the section of the Entrada Sandstone just above the Carmel Fm. The permeability of the polygonal deformation bands is approximately 10-14 to 10-13 m2, which is less than the permeability of the host, Entrada Sandstone (range 10-12 to 10-11 m2). The documented fault networks have important implications for evaluating the geometry of km-scale polygonal fault systems in the subsurface, top seal integrity, as well as constraining paleo-tectonic stress regimes.

Occurrence of oral deformities in larval anurans

USGS Publications Warehouse

Drake, D.L.; Altig, R.; Grace, J.B.; Walls, S.C.

2007-01-01

We quantified deformities in the marginal papillae, tooth rows, and jaw sheaths of tadpoles from 13 population samples representing three families and 11 sites in the southeastern United States. Oral deformities were observed in all samples and in 13.5-98% of the specimens per sample. Batrachochytrium dendrobatidis (chytrid) infections were detected in three samples. There was high variability among samples in the pattern and number of discovered deformities. Pairwise associations between oral structures containing deformities were nonrandom for several populations, especially those with B. dendrobatidis infections or high total numbers of deformities. Comparisons of deformities among samples using multivariate analyses revealed that tadpole samples grouped together by family. Analyses of ordination indicated that three variables, the number of deformities, the number of significant associations among deformity types within populations, and whether populations were infected with B. dendrobatidis, were significantly correlated with the pattern of deformities. Our data indicate that the incidence of oral deformities can be high in natural populations and that phylogeny and B. dendrobatidis infection exert a strong influence on the occurrence and type of oral deformities in tadpoles. ?? by the American Society of Ichthyologists and Herperologists.

Kyste épidermoïde du testicule : Étude de cas

PubMed Central

Diarra, Alkadri; Elammari, Jalal Eddine; Kassogue, Amadou; El Fassi, Mohammed Jamal; Farih, My Hassan

2013-01-01

Résumé Le kyste épidermoïde (KE) du testicule est une tumeur bénigne rare. Le diagnostic peut être évoqué par l’échographie et l’IRM. En cas de lésion unique de petite taille, il est possible d’effectuer une chirurgie conservatrice. Ce traitement nécessite une confirmation anatomopathologique. Le présent article fait état de l’observation d’un patient de 34 ans ayant été admis en consultation d’urologie pour désir d’enfant. Le diagnostic de KE associé à une varicocèle gauche a été retenu. L’énucléation du kyste avec cure de varicocèle a été réalisée sans complications postopératoires. Une revue de la littérature nous a permis de mettre en évidence les différents aspects du KE du testicule et les méthodes thérapeutiques envisageables. PMID:24282476

Des proprietes de l'etat normal du modele de Hubbard bidimensionnel

NASA Astrophysics Data System (ADS)

Lemay, Francois

Depuis leur decouverte, les etudes experimentales ont demontre que les supra-conducteurs a haute temperature ont une phase normale tres etrange. Les proprietes de ces materiaux ne sont pas bien decrites par la theorie du liquide de Fermi. Le modele de Hubbard bidimensionnel, bien qu'il ne soit pas encore resolu, est toujours considere comme un candidat pour expliquer la physique de ces composes. Dans cet ouvrage, nous mettons en evidence plusieurs proprietes electroniques du modele qui sont incompatibles avec l'existence de quasi-particules. Nous montrons notamment que la susceptibilite des electrons libres sur reseau contient des singularites logarithmiques qui influencent de facon determinante les proprietes de la self-energie a basse frequence. Ces singularites sont responsables de la destruction des quasi-particules. En l'absence de fluctuations antiferromagnetiques, elles sont aussi responsables de l'existence d'un petit pseudogap dans le poids spectral au niveau de Fermi. Les proprietes du modele sont egalement etudiees pour une surface de Fermi similaire a celle des supraconducteurs a haute temperature. Un parallele est etabli entre certaines caracteristiques du modele et celles de ces materiaux.

Two-generation reproductive toxicity study of implanted depleted uranium (DU) in CD rats.

PubMed

Arfsten, D P; Still, K R; Wilfong, E R; Johnson, E W; McInturf, S M; Eggers, J S; Schaeffer, D J; Bekkedal, M Y-V

2009-01-01

Depleted uranium (DU) munitions and armor plating have been used in several conflicts over the last 17 yr, including the Persian Gulf War and the Iraq War. Because of its effectiveness and availability, DU will continue to be used in military applications into the foreseeable future. There is much controversy over the use of DU in weapons and equipment because of its potential radiological and toxic hazards, and there is concern over the chronic adverse health effects of embedded DU shrapnel in war veterans and bystanders. This study evaluated the effects of long-term implantation of DU on the reproductive success of F0 generation adults and development and survival of subsequent F1 and F2 generations in a two-generation reproductive toxicity study. F0 generation Sprague-Dawley rats, 8 wk of age, were surgically implanted with 0, 4, 8, 12, or 20 DU pellets (1 x 2 mm). Inert implant control animals were implanted with 12 or 20 tantallum (Ta) pellets. The F0 generation was then mated at 120 d post DU implantation. In the F0 generation, when measured on postimplantation d 27 and 117, uranium was present in the urine of DU-implanted animals in a dose-dependent manner. F0 reproductive success was similar across treatment groups and the maternal retrieval test revealed no changes in maternal behavior. DU implantation exerted no effect on the survival, health, or well-being of the F0 generation. Necropsy results of F0 animals were negative with the exception of a marked inflammatory response surrounding the implanted DU pellets. For the F1 generation, measures of F1 development through postnatal day (PND) 20 were unremarkable and no gross abnormalities were observed in F1 offspring. No uranium was detected in whole-body homogenates of PND 4 or PND 20 pups. Necropsy findings of F1 PND 20 pups were negative and no instances of ribcage malformation were observed in F1 PND 20 pups. Body weight and body weight gain of F1 rats through PND 120 were similar across treatment

Facies Analysis of the Tandoǧdu Travertines, Van, Eastern Anatolia, Turkey: implications for the active tectonic deformation behind the formation and evolution of the travertines

NASA Astrophysics Data System (ADS)

Yesilova, Cetin; Yesilova, Pelin; Aclan, Mustafa; Gülyüz, Nilay

2017-04-01

In this study, stratigraphic and sedimentologic characteristics of Tandoǧdu travertines exposing at the 13 km southwest of Başkale, Van were examined. In this respect, we shed light on their formation conditions and depositional environment by determining their morphological characteristics and analyzing their facies distribution. In addition, kinematic studies were conducted by collecting structural data from the structures hosting the travertines. Tandoǧdu travertines having bed type and ridge type travertines have 5 distinct lithofacies based on the studies conducted. These are: (1) crystalline crust facies, (2) coated bubble facies, (3) paper-thin raft type facies, (4) lithoclast - breccia facies and (5) paleosoil facies. According to the examination of their morphologies and lithofacies; lithofacies were developed depending on the temperature of fluids forming the travertines. Distal from the source field of the hydrothermal fluids, paper-thin raft type facies were developed in shallow pools. Proximal to the source field of the hydrothermal fluids, crystalline crust facies and coated bubble facies were deposited. Existence of breccia facies indicates the effects of active tectonism during the formation of travertines. Hot hydrothermal pools on the ridge type travertines prove the still active tectonic activities. On-going studies aim to date growth of the travertines by U-Th dating method which will also shed some light on the tectonic scenario behind the evolution of the travertines.

Speaking Truth to Power: Du Bois as Educator and Community Activist

ERIC Educational Resources Information Center

Grant, Carl A.; Grant, Paul D.

2017-01-01

This article uses W. E. B. Du Bois's work as an education and community activist to discuss race, oppression, and speaking-back to power in this time of racialized policies enacted by the Trump administration. This article centers a comparative discussion of the racialization of democracy by presidents Wilson and Trump to show the ways Du Bois was…

Behavior of lateral-deformation coefficients during elastoplastic deformation of metals

NASA Astrophysics Data System (ADS)

Zimin, B. A.; Smirnov, I. V.; Sudenkov, Yu. V.

2017-06-01

The results of investigations into variation of the coefficients of lateral deformation (the Poisson ratio) during single-axis tension of samples of steel 12Kh18N10T and St3, titanium VT1, the aluminum alloy D16AM, copper M1, and a magnesium alloy are considered. The technique developed on the basis of the optoacoustic effect and simultaneous measurements of the longitudinal and surface speeds of sound in metallic samples during the tension makes it possible to measure the rates at various stages of the deformation process. The data obtained make it possible to construct the dependences of variation of the lateral-deformation coefficients at all stages of the plastic flow. The correlation of these variations both with known processes of structural reconstructions at various stages of plastic flow and with the process of localization of plastic-shear bands in the aluminum alloy is noted.

Evaluation du niveau de connaissance des patients sur la gestion du traitement par les antis vitamines K dans le service de cardiologie de Ouagadougou

PubMed Central

Samadoulougou, André; Temoua Naibe, Dangwé; Mandi, Germain; Yameogo, Relwendé Aristide; Kabore, Elisé; Millogo, Georges; Yameogo, Nobila Valentin; Kologo, Jonas Koudougou; Thiam/Tall, Anna; Toguyeni, Boubacar Jean Yves; Zabsonre, Patrice

2014-01-01

Introduction Les antivitamines K (AVK), traitement anticoagulant oral le plus largement prescrit, posent un réel problème de santé publique du fait de leur risque iatrogène. L'objectif de cette étude était de préciser le niveau de connaissance des patients sur la gestion de leur traitement par les AVK. Méthodes Il s'est agi d'une enquête transversale descriptive réalisée au CHU-Yalgado Ouédraogo, sur une période de 03 mois : du 1er mars au 31 mai 2012. Un questionnaire a été administré aux patients bénéficiant d'un traitement AVK depuis au moins un mois. Résultats Soixante-dix patients ont été inclus dans l'étude dont 30 hommes. L'âge moyen était de 49 ans ± 16 ans. Les cardiopathies et la maladie thromboembolique veineuse justifiant l'institution du traitement AVK étaient retrouvées respectivement dans 58,6% et 41,4% des cas. Le nom de l'AVK et la raison exacte du traitement étaient connus respectivement dans 91,4% et 67,1% des cas. Plus de la moitié des patients (68,6%) savaient que les AVK rendaient le sang plus fluide. Quarante-six patients (65,7%) citaient l'INR comme examen biologique de surveillance du traitement et seulement 28 patients (40%) connaissaient les valeurs cibles. La majorité des patients ne connaissait pas les risques encourus en cas de surdosage (72,8%) et de sous-dosage (71,4%). Une automédication par anti-inflammatoire non stéroïdien était signalée par 18 patients (25,7%). Les choux (74,3%) et la laitue (62,9%), aliments à consommer avec modération, étaient les plus cités. Conclusion Les connaissances des patients sur la gestion des AVK étaient fragmentaires et insuffisantes pour assurer la sécurité et l'efficacité du traitement. La création d'un programme d'éducation thérapeutique sur les AVK s'avère alors nécessaire. PMID:25870741

Deformation-Aware Log-Linear Models

NASA Astrophysics Data System (ADS)

Gass, Tobias; Deselaers, Thomas; Ney, Hermann

In this paper, we present a novel deformation-aware discriminative model for handwritten digit recognition. Unlike previous approaches our model directly considers image deformations and allows discriminative training of all parameters, including those accounting for non-linear transformations of the image. This is achieved by extending a log-linear framework to incorporate a latent deformation variable. The resulting model has an order of magnitude less parameters than competing approaches to handling image deformations. We tune and evaluate our approach on the USPS task and show its generalization capabilities by applying the tuned model to the MNIST task. We gain interesting insights and achieve highly competitive results on both tasks.

Watershed Data Management (WDM) database for West Branch DuPage River streamflow simulation, DuPage County, Illinois, January 1, 2007, through September 30, 2013

USGS Publications Warehouse

Bera, Maitreyee

2017-10-16

The U.S. Geological Survey (USGS), in cooperation with the DuPage County Stormwater Management Department, maintains a database of hourly meteorological and hydrologic data for use in a near real-time streamflow simulation system. This system is used in the management and operation of reservoirs and other flood-control structures in the West Branch DuPage River watershed in DuPage County, Illinois. The majority of the precipitation data are collected from a tipping-bucket rain-gage network located in and near DuPage County. The other meteorological data (air temperature, dewpoint temperature, wind speed, and solar radiation) are collected at Argonne National Laboratory in Argonne, Ill. Potential evapotranspiration is computed from the meteorological data using the computer program LXPET (Lamoreux Potential Evapotranspiration). The hydrologic data (water-surface elevation [stage] and discharge) are collected at U.S.Geological Survey streamflow-gaging stations in and around DuPage County. These data are stored in a Watershed Data Management (WDM) database.This report describes a version of the WDM database that is quality-assured and quality-controlled annually to ensure datasets are complete and accurate. This database is named WBDR13.WDM. It contains data from January 1, 2007, through September 30, 2013. Each precipitation dataset may have time periods of inaccurate data. This report describes the methods used to estimate the data for the periods of missing, erroneous, or snowfall-affected data and thereby improve the accuracy of these data. The other meteorological datasets are described in detail in Over and others (2010), and the hydrologic datasets in the database are fully described in the online USGS annual water data reports for Illinois (U.S. Geological Survey, 2016) and, therefore, are described in less detail than the precipitation datasets in this report.

Rapport sur l'état du patrimoine astronomique dans les observatoires français de la fin du XIXè siècle

NASA Astrophysics Data System (ADS)

Damm, E.; Pécontal, E.

2012-12-01

Suite au colloque sur la sauvegarde du patrimoine astronomique organisé par le MAEE et la SAF, sous l'égide de l'UNESCO, qui a conduit à l'adoption de la Déclaration de Paris, les directeurs d'observatoires institutionnels qui étaient absents du colloque ont ressenti le besoin de discuter de ces conclusions prises en leur nom. L'initiative d'organiser une réunion des directeurs des Observatoires des Sciences de l'Univers (OSU) à ce sujet le 30 janvier 2012 a été prise par François Vernotte, directeur de l'Observatoire de Besançon. Le présent compte-rendu de visite résulte d'une initiative spontanée d'Emmanuel Pécontal, astronome responsable du Patrimoine à l'observatoire de Lyon, et d'Evelyne Damm, membre de la Commission Nationale de classement des Monuments Historiques (CNMH) et élue à la communauté d'agglomération des Portes de l'Essonne oû est sis l'observatoire de Camille Flammarion.

Non-affine deformations in polymer hydrogels

PubMed Central

Wen, Qi; Basu, Anindita; Janmey, Paul A.; Yodh, A. G.

2012-01-01

Most theories of soft matter elasticity assume that the local strain in a sample after deformation is identical everywhere and equal to the macroscopic strain, or equivalently that the deformation is affine. We discuss the elasticity of hydrogels of crosslinked polymers with special attention to affine and non-affine theories of elasticity. Experimental procedures to measure non-affine deformations are also described. Entropic theories, which account for gel elasticity based on stretching out individual polymer chains, predict affine deformations. In contrast, simulations of network deformation that result in bending of the stiff constituent filaments generally predict non-affine behavior. Results from experiments show significant non-affine deformation in hydrogels even when they are formed by flexible polymers for which bending would appear to be negligible compared to stretching. However, this finding is not necessarily an experimental proof of the non-affine model for elasticity. We emphasize the insights gained from experiments using confocal rheoscope and show that, in addition to filament bending, sample micro-inhomogeneity can be a significant alternative source of non-affine deformation. PMID:23002395

Quantifying the Erlenmeyer flask deformity

PubMed Central

Carter, A; Rajan, P S; Deegan, P; Cox, T M; Bearcroft, P

2012-01-01

Objective Erlenmeyer flask deformity is a common radiological finding in patients with Gaucher′s disease; however, no definition of this deformity exists and the reported prevalence of the deformity varies widely. To devise an easily applied definition of this deformity, we investigated a cohort of knee radiographs in which there was consensus between three experienced radiologists as to the presence or absence of Erlenmeyer flask morphology. Methods Using the presence or absence of Erlenmeyer flask morphology as a benchmark, we measured the diameter of the femur at the level of the physeal scar and serially at defined intervals along the metadiaphysis. Results A measured ratio in excess of 0.57 between the diameter of the femoral shaft 4 cm from the physis to the diameter of the physeal baseline itself on a frontal radiograph of the knee predicted the Erlenmeyer flask deformity with 95.6% sensitivity and 100% specificity in our series of 43 independently diagnosed adults with Gaucher′s disease. Application of this method to the distal femur detected the Erlenmeyer flask deformity reproducibly and was simple to carry out. Conclusion Unlike diagnostic assignments based on subjective review, our simple procedure for identifying the modelling deformity is based on robust quantitative measurement: it should facilitate comparative studies between different groups of patients, and may allow more rigorous exploration of the pathogenesis of the complex osseous manifestations of Gaucher′s disease to be undertaken. PMID:22010032

Locke and Du Bois: Two Major Black Voices Muzzled by Philanthropic Organizations.

ERIC Educational Resources Information Center

Fitchue, M. Anthony

1997-01-01

In 1935, the Howard University philosopher Alain Locke asked W. E. B. Du Bois to contribute to an adult education project for African Americans. Censorship by white-controlled foundations forced Locke to reject the Du Bois essay to protect contributions for causes of great importance to blacks. (Author/SLD)

Slow deformation of intervertebral discs.

PubMed

Broberg, K B

1993-01-01

Intervertebral discs exhibit pronounced time-dependent deformations when subjected to load variations. These deformations are caused by fluid flow to and from the disc and by viscoelastic deformation of annulus fibres. The fluid flow is caused by differences between mechanical and osmotic pressure. A mechanical model of lumbar disc functions allows one to calculate both the extent of fluid flow and its implications for disc height as well as the role played by viscoelastic deformation of annulus fibres. From such calculations changes in body height are estimated. Experimental results already documented in the literature offer bases for the determination of the parameters involved. Body height variations are studied, both those related to normal diurnal rhythmicity and those related to somewhat exceptional circumstances. The normal diurnal fluid flow is found to be about +/- 40% of the disc fluid content late in the evening. Viscoelastic deformation of annulus fibres contributes approximately one quarter of the height change obtained after several hours normal activity, but dominates during the first hour.

Patterns of Alloy Deformation by Pulsed Pressure

NASA Astrophysics Data System (ADS)

Chebotnyagin, L. M.; Potapov, V. V.; Lopatin, V. V.

2015-06-01

Patterns of alloy deformation for optimization of a welding regime are studied by the method of modeling and deformation profiles providing high deformation quality are determined. A model of stepwise kinetics of the alloy deformation by pulsed pressure from the expanding plasma channel inside of a deformable cylinder is suggested. The model is based on the analogy between the acoustic and electromagnetic wave processes in long lines. The shock wave pattern of alloy deformation in the presence of multiple reflections of pulsed pressure waves in the gap plasma channel - cylinder wall and the influence of unloading waves from free surfaces are confirmed.

Developing a Virtual Rock Deformation Laboratory

NASA Astrophysics Data System (ADS)

Zhu, W.; Ougier-simonin, A.; Lisabeth, H. P.; Banker, J. S.

2012-12-01

Experimental rock physics plays an important role in advancing earthquake research. Despite its importance in geophysics, reservoir engineering, waste deposits and energy resources, most geology departments in U.S. universities don't have rock deformation facilities. A virtual deformation laboratory can serve as an efficient tool to help geology students naturally and internationally learn about rock deformation. Working with computer science engineers, we built a virtual deformation laboratory that aims at fostering user interaction to facilitate classroom and outreach teaching and learning. The virtual lab is built to center around a triaxial deformation apparatus in which laboratory measurements of mechanical and transport properties such as stress, axial and radial strains, acoustic emission activities, wave velocities, and permeability are demonstrated. A student user can create her avatar to enter the virtual lab. In the virtual lab, the avatar can browse and choose among various rock samples, determine the testing conditions (pressure, temperature, strain rate, loading paths), then operate the virtual deformation machine to observe how deformation changes physical properties of rocks. Actual experimental results on the mechanical, frictional, sonic, acoustic and transport properties of different rocks at different conditions are compiled. The data acquisition system in the virtual lab is linked to the complied experimental data. Structural and microstructural images of deformed rocks are up-loaded and linked to different deformation tests. The integration of the microstructural image and the deformation data allows the student to visualize how forces reshape the structure of the rock and change the physical properties. The virtual lab is built using the Game Engine. The geological background, outstanding questions related to the geological environment, and physical and mechanical concepts associated with the problem will be illustrated on the web portal. In

Coalition Battle Management Language (C-BML) (Language de gestion du champ de bataille (C-BML)

DTIC Science & Technology

2012-02-01

de gestion du champ de bataille (C-BML)) NMSG-048 Final Report. This document...BML) (Langage de gestion du champ de bataille (C-BML)) NMSG-048 Final Report. This document contains information authorized by NATO RTA for...Technical Readiness Level (TRL) that is consistent with an operational deployment. ES - 2 RTO-TR-MSG-048 Langage de gestion du champ de

Deformable mirrors development program at ESO

NASA Astrophysics Data System (ADS)

Stroebele, Stefan; Vernet, Elise; Brinkmann, Martin; Jakob, Gerd; Lilley, Paul; Casali, Mark; Madec, Pierre-Yves; Kasper, Markus

2016-07-01

Over the last decade, adaptive optics has become essential in different fields of research including medicine and industrial applications. With this new need, the market of deformable mirrors has expanded a lot allowing new technologies and actuation principles to be developed. Several E-ELT instruments have identified the need for post focal deformable mirrors but with the increasing size of the telescopes the requirements on the deformable mirrors become more demanding. A simple scaling up of existing technologies from few hundred actuators to thousands of actuators will not be sufficient to satisfy the future needs of ESO. To bridge the gap between available deformable mirrors and the future needs for the E-ELT, ESO started a development program for deformable mirror technologies. The requirements and the path to get the deformable mirrors for post focal adaptive optics systems for the E-ELT is presented.

Variable focal length deformable mirror

DOEpatents

Headley, Daniel [Albuquerque, NM; Ramsey, Marc [Albuquerque, NM; Schwarz, Jens [Albuquerque, NM

2007-06-12

A variable focal length deformable mirror has an inner ring and an outer ring that simply support and push axially on opposite sides of a mirror plate. The resulting variable clamping force deforms the mirror plate to provide a parabolic mirror shape. The rings are parallel planar sections of a single paraboloid and can provide an on-axis focus, if the rings are circular, or an off-axis focus, if the rings are elliptical. The focal length of the deformable mirror can be varied by changing the variable clamping force. The deformable mirror can generally be used in any application requiring the focusing or defocusing of light, including with both coherent and incoherent light sources.

Hématome spontané du méso de l'angle colique droit et du colon transverse compliquant un traitement par anti vitamine K: à propos d'un cas et revue de la littérature

PubMed Central

Traoré, Ibrahim Alain; Zaré, Cyprien; Barro, Sié Drissa; Guibla, Ismaël

2016-01-01

L'hématome spontané du méso de l'angle colique droit et du transverse est une complication rare du traitement anticoagulant par antivitamine K. Nous rapportons un cas d'hématome spontané du méso de l'angle colique droit et du transverse associé à un hémopéritoine de grande abondance chez un patient traité par antivitamine K pour embolie pulmonaire consécutive à une fracture des plateaux tibiaux droits. Le diagnostic doit être fait en urgence. L’échographie abdominale et la tomodensitométrie confirment le diagnostic. Le traitement non opératoire est la règle. Le traitement chirurgical est indiqué en cas de complications telles que la rupture de l'hématome. PMID:27217878

Characterization of FaDu-R, a radioresistant head and neck cancer cell line, and cancer stem cells.

PubMed

Cho, Kwang-Jae; Park, Eun-Ji; Kim, Min-Sik; Joo, Young-Hoon

2018-06-01

The aim of this study was to evaluate the impact of CSC on insensitivity to radiotherapy in HNSCC. A radioresistant cell line, FaDu-R, was established using fractionated ionizing radiation. Cells with high and low CD44/ALDH activity were isolated. FaDu-R cells demonstrated significantly increased cell viability after radiation exposure compared with parental cells. CD44 high /ALDH high FaDu-R cells demonstrated significantly faster wound closure (p<0.05) and more efficient invasion (p<0.05) compared to the CD44 high /ALDH high FaDu cells or the CD44 low /ALDH low FaDu-R cells. There was a significant difference in tumor volume between the CD44 high /ALDH high FaDu-R cells and the CD44 high /ALDH high FaDu cells (p<0.05) as well as the CD44 low /ALDH low FaDu-R cells (p<0.05). Cancer stem cells (CSC) were associated with invasion and tumorigenesis in a radioresistant head and neck squamous cell carcinoma (HNSCC) cell line. This concept might help to improve the understanding of these mechanisms and to develop drugs that can overcome radioresistance during radiotherapy. Copyright © 2017 Elsevier B.V. All rights reserved.

Genetics Home Reference: cri-du-chat syndrome

MedlinePlus

... Pinkel D. High-resolution mapping of genotype-phenotype relationships in cri du chat syndrome using array comparative ... for Links Data Files & API Site Map Subscribe Customer Support USA.gov Copyright Privacy Accessibility FOIA Viewers & ...

Modelisation frequentielle de la permittivite du beton pour le controle non destructif par georadar

NASA Astrophysics Data System (ADS)

Bourdi, Taoufik

Le georadar (Ground Penetrating Radar (GPR)) constitue une technique de controle non destructif (CND) interessante pour la mesure des epaisseurs des dalles de beton et la caracterisation des fractures, en raison de ses caracteristiques de resolution et de profondeur de penetration. Les equipements georadar sont de plus en plus faciles a utiliser et les logiciels d'interpretation sont en train de devenir plus aisement accessibles. Cependant, il est ressorti dans plusieurs conferences et ateliers sur l'application du georadar en genie civil qu'il fallait poursuivre les recherches, en particulier sur la modelisation et les techniques de mesure des proprietes electriques du beton. En obtenant de meilleures informations sur les proprietes electriques du beton aux frequences du georadar, l'instrumentation et les techniques d'interpretation pourraient etre perfectionnees plus efficacement. Le modele de Jonscher est un modele qui a montre son efficacite dans le domaine geophysique. Pour la premiere fois, son utilisation dans le domaine genie civil est presentee. Dans un premier temps, nous avons valide l'application du modele de Jonscher pour la caracterisation de la permittivite dielectrique du beton. Les resultats ont montre clairement que ce modele est capable de reproduire fidelement la variation de la permittivite de differents types de beton sur la bande de frequence georadar (100 MHz-2 GHz). Dans un deuxieme temps, nous avons montre l'interet du modele de Jonscher en le comparant a d'autres modeles (Debye et Debye-etendu) deja utilises dans le domaine genie civil. Nous avons montre aussi comment le modele de Jonscher peut presenter une aide a la prediction de l'efficacite de blindage et a l'interpretation des ondes de la technique GPR. Il a ete determine que le modele de Jonscher permet de donner une bonne presentation de la variation de la permittivite du beton dans la gamme de frequence georadar consideree. De plus, cette modelisation est valable pour differents

Intraplate deformation due to continental collisions: A numerical study of deformation in a thin viscous sheet

NASA Technical Reports Server (NTRS)

Cohen, S. C.; Morgan, R. C.

1985-01-01

A model of crustal deformation from continental collision that involves the penetration of a rigid punch into a deformable sheet is investigated. A linear viscous flow law is used to compute the magnitude and rate of change of crustal thickness, the velocity of mass points, strain rates and their principal axes, modes of deformation, areal changes, and stress. In general, a free lateral boundary reduces the magnitude of changes in crustal thickening by allowing material to more readily escape the advancing punch. The shearing that occurs diagonally in front of the punch terminates in compression or extension depending on whether the lateral boundary is fixed or free. When the ratio of the diameter of the punch to that of the sheet exceeds one-third, the deformation is insenstive to the choice of lateral boundary conditions. When the punch is rigid with sharply defined edges, deformation is concentrated near the punch corners. With non-rigid punches, shearing results in deformation being concentrated near the center of the punch. Variations with respect to linearity and nonlinearity of flow are discussed.

Cooperative deformations of periodically patterned hydrogels.

PubMed

Wang, Zhi Jian; Zhu, Chao Nan; Hong, Wei; Wu, Zi Liang; Zheng, Qiang

2017-09-01

Nature has shown elegant paradigms of smart deformation, which inspired biomimetic systems with controllable bending, folding, and twisting that are significant for the development of soft electronics and actuators. Complex deformations are usually realized by additively incorporating typical structures in selective domains with little interaction. We demonstrate the cooperative deformations of periodically patterned hydrogel sheets, in which neighboring domains mutually interact and cooperatively deform. Nonswelling disc gels are periodically positioned in a high-swelling gel. During the swelling process, the compartmentalized high-swelling gel alternately bends upward or downward to relieve the in-plane compression, but the overall integrated structure remains flat. The synergy between the elastic mismatch and the geometric periodicity selects the outcome pattern. Both experiment and modeling show that various types of cooperative deformation can be achieved by tuning the pattern geometry and gel properties. Different responsive polymers can also be patterned in one composite gel. Under stimulation, reversible transformations between different cooperative deformations are realized. The principle of cooperative deformation should be applicable to other materials, and the patterns can be miniaturized to the micrometer- or nanometer-scale level, providing the morphing materials with advanced functionalities for applications in various fields.

Perceptual transparency from image deformation.

PubMed

Kawabe, Takahiro; Maruya, Kazushi; Nishida, Shin'ya

2015-08-18

Human vision has a remarkable ability to perceive two layers at the same retinal locations, a transparent layer in front of a background surface. Critical image cues to perceptual transparency, studied extensively in the past, are changes in luminance or color that could be caused by light absorptions and reflections by the front layer, but such image changes may not be clearly visible when the front layer consists of a pure transparent material such as water. Our daily experiences with transparent materials of this kind suggest that an alternative potential cue of visual transparency is image deformations of a background pattern caused by light refraction. Although previous studies have indicated that these image deformations, at least static ones, play little role in perceptual transparency, here we show that dynamic image deformations of the background pattern, which could be produced by light refraction on a moving liquid's surface, can produce a vivid impression of a transparent liquid layer without the aid of any other visual cues as to the presence of a transparent layer. Furthermore, a transparent liquid layer perceptually emerges even from a randomly generated dynamic image deformation as long as it is similar to real liquid deformations in its spatiotemporal frequency profile. Our findings indicate that the brain can perceptually infer the presence of "invisible" transparent liquids by analyzing the spatiotemporal structure of dynamic image deformation, for which it uses a relatively simple computation that does not require high-level knowledge about the detailed physics of liquid deformation.

Unclassified congenital deformities of the external ear.

PubMed

Vathulya, Madhubari

2018-01-01

Congenital ear deformities are a common entity. They are found in isolation or as a part of syndrome in patients. They may involve the external, middle or inner ear or in any of these combinations. Three patients of different ages presented with deformities including mirror image duplication of the superior auricle, unclassified deformities of ear lobule (wavy lobule) and deformity of superior auricle with unclassified variety of lateral ear pit. This article highlights that there are further cases of ear deformities that are noticed in the general population who come for cosmetic correction, and hence, there is a need for further modifying the classification of ear deformities.

Deforming regular black holes

NASA Astrophysics Data System (ADS)

Neves, J. C. S.

2017-06-01

In this work, we have deformed regular black holes which possess a general mass term described by a function which generalizes the Bardeen and Hayward mass functions. By using linear constraints in the energy-momentum tensor to generate metrics, the solutions presented in this work are either regular or singular. That is, within this approach, it is possible to generate regular or singular black holes from regular or singular black holes. Moreover, contrary to the Bardeen and Hayward regular solutions, the deformed regular black holes may violate the weak energy condition despite the presence of the spherical symmetry. Some comments on accretion of deformed black holes in cosmological scenarios are made.

L'Abondance du Deutérium, de l'Ultraviolet au Visible

NASA Astrophysics Data System (ADS)

Hébrard, Guillaume

2000-12-01

Dans le cadre du modèle standard du Big Bang, le deutérium est l'élément dont l'abondance primordiale est la plus sensible à la densité baryonique de l'Univers. Cet élément est uniquement créé lors de la nucléosynthèse primordiale, quelques minutes après le Big Bang ; aucune théorie standard n'en prédit actuellement d'autres sources significatives. Au contraire, étant brûlé dans les étoiles, son abondance D/H décroît au cours de l'évolution cosmique. Les mesures de D/H apportent ainsi des contraintes sur les modèles de Big Bang et d'évolution chimique des galaxies. On peut distinguer trois types de mesures de D/H: les abondances primordiale, proto-solaire et interstellaire, respectivement représentatives de l'Univers il y a environ 15 milliards d'années, 4.5 milliards d'années et à l'époque actuelle. Si l'évolution du deutérium semble qualitativement claire, les résultats concernant ces trois types d'abondance ne convergent pas pour l'instant vers trois valeurs bien définies. Les travaux entrepris durant cette thèse sont reliés à la mesure de l'abondance interstellaire du deutérium. Celle-ci s'obtient habituellement par l'observation spectroscopique en absorption des séries de Lyman de l'hydrogène et du deutérium. Ces observations se font dans le domaine ultraviolet, au moyen d'observatoires spatiaux. Les résultats présentés ici ont été obtenus avec le Télescope spatial Hubble puis le satellite FUSE, récemment mis en orbite. D'autre part, une nouvelle méthode d'observation du deutérium a été proposée, dans le domaine visible à partir de télescopes au sol. Ce travail a mené aux premières détections et à l'identification de la série de Balmer du deutérium, observée en émission dans des régions HII avec le Télescope Canada-France-Hawaii et le Very Large Telescope. On-line Thesis, Guillaume Hébrard

Static response of deformable microchannels

NASA Astrophysics Data System (ADS)

Christov, Ivan C.; Sidhore, Tanmay C.

2017-11-01

Microfluidic channels manufactured from PDMS are a key component of lab-on-a-chip devices. Experimentally, rectangular microchannels are found to deform into a non-rectangular cross-section due to fluid-structure interactions. Deformation affects the flow profile, which results in a nonlinear relationship between the volumetric flow rate and the pressure drop. We develop a framework, within the lubrication approximation (l >> w >> h), to self-consistently derive flow rate-pressure drop relations. Emphasis is placed on handling different types of elastic response: from pure plate-bending, to half-space deformation, to membrane stretching. The ``simplest'' model (Stokes flow in a 3D rectangular channel capped with a linearly elastic Kirchhoff-Love plate) agrees well with recent experiments. We also simulate the static response of such microfluidic channels under laminar flow conditions using ANSYSWorkbench. Simulations are calibrated using experimental flow rate-pressure drop data from the literature. The simulations provide highly resolved deformation profiles, which are difficult to measure experimentally. By comparing simulations, experiments and our theoretical models, we show good agreement in many flow/deformation regimes, without any fitting parameters.

Quantifying torso deformity in scoliosis

NASA Astrophysics Data System (ADS)

Ajemba, Peter O.; Kumar, Anish; Durdle, Nelson G.; Raso, V. James

2006-03-01

Scoliosis affects the alignment of the spine and the shape of the torso. Most scoliosis patients and their families are more concerned about the effect of scoliosis on the torso than its effect on the spine. There is a need to develop robust techniques for quantifying torso deformity based on full torso scans. In this paper, deformation indices obtained from orthogonal maps of full torso scans are used to quantify torso deformity in scoliosis. 'Orthogonal maps' are obtained by applying orthogonal transforms to 3D surface maps. (An 'orthogonal transform' maps a cylindrical coordinate system to a Cartesian coordinate system.) The technique was tested on 361 deformed computer models of the human torso and on 22 scans of volunteers (8 normal and 14 scoliosis). Deformation indices from the orthogonal maps correctly classified up to 95% of the volunteers with a specificity of 1.00 and a sensitivity of 0.91. In addition to classifying scoliosis, the system gives a visual representation of the entire torso in one view and is viable for use in a clinical environment for managing scoliosis.

Volcanic deformation in the Andes

NASA Astrophysics Data System (ADS)

Riddick, S.; Fournier, T.; Pritchard, M.

2009-05-01

We present the results from an InSAR survey of volcanic activity in South America. We use data from the Japanese Space Agency's ALOS L-band radar satellite from 2006-2009. The L-band instrument provides better coherence in densely vegetated regions, compared to the shorter wave length C-band data. The survey reveals volcano related deformation in regions, north, central and southern, of the Andes volcanic arc. Since observations are limited to the austral summer, comprehensive coverage of all volcanoes is not possible. Yet, our combined observations reveal volcanic/hydrothermal deformation at Lonquimay, Llaima, Laguna del Maule, and Chaitén volcanoes, extend deformation measurements at Copahue, and illustrate temporal complexity to the previously described deformation at Cerro Hudson and Cordón Caulle. No precursory deformation is apparent before the large Chaitén eruption (VEI_5) of 2 May 2008, (at least before 16 April) suggesting rapid magma movement from depth at this long dormant volcano. Subsidence at Ticsani Volcano occurred coincident with an earthquake swarm in the same region.

State-variable theories for nonelastic deformation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Li, C.Y.

The various concepts of mechanical equation of state for nonelastic deformation in crystalline solids, originally proposed for plastic deformation, have been recently extended to describe additional phenomena such as anelastic and microplastic deformation including the Bauschinger effect. It has been demonstrated that it is possible to predict, based on current state variables in a unified way, the mechanical response of a material under an arbitrary loading. Thus, if the evolution laws of the state variables are known, one can describe the behavior of a material for a thermal-mechanical path of interest, for example, during constant load (or stress) creep withoutmore » relying on specialized theories. Some of the existing theories of mechanical equation of state for nonelastic deformation are reviewed. The establishment of useful forms of mechanical equation of state has to depend on extensive experimentation in the same way as that involved in the development, for example, the ideal gas law. Recent experimental efforts are also reviewed. It has been possible to develop state-variable deformation models based on experimental findings and apply them to creep, cyclic deformation, and other time-dependent deformation. Attempts are being made to correlate the material parameters of the state-variable models with the microstructure of a material. 24 figures.« less

College of DuPage Planning Process: College of DuPage Planning, the Foundation for Decision Making.

ERIC Educational Resources Information Center

College of DuPage, Glen Ellyn, IL. Office of Research and Planning.

At College of DuPage (CD), in Glen Ellyn, Illinois, institutional planning is a multi-level, on-going process involving continuous college-wide input. The nine schematic levels in the CD planning process are interconnected and progress from global and broad-based issues, answering such questions as why the college exists, to concrete levels…

Physics-based deformable organisms for medical image analysis

NASA Astrophysics Data System (ADS)

Hamarneh, Ghassan; McIntosh, Chris

2005-04-01

Previously, "Deformable organisms" were introduced as a novel paradigm for medical image analysis that uses artificial life modelling concepts. Deformable organisms were designed to complement the classical bottom-up deformable models methodologies (geometrical and physical layers), with top-down intelligent deformation control mechanisms (behavioral and cognitive layers). However, a true physical layer was absent and in order to complete medical image segmentation tasks, deformable organisms relied on pure geometry-based shape deformations guided by sensory data, prior structural knowledge, and expert-generated schedules of behaviors. In this paper we introduce the use of physics-based shape deformations within the deformable organisms framework yielding additional robustness by allowing intuitive real-time user guidance and interaction when necessary. We present the results of applying our physics-based deformable organisms, with an underlying dynamic spring-mass mesh model, to segmenting and labelling the corpus callosum in 2D midsagittal magnetic resonance images.

Perioperative Assessment of Myocardial Deformation

PubMed Central

Duncan, Andra E.; Alfirevic, Andrej; Sessler, Daniel I.; Popovic, Zoran B.; Thomas, James D.

2014-01-01

Evaluation of left ventricular performance improves risk assessment and guides anesthetic decisions. However, the most common echocardiographic measure of myocardial function, the left ventricular ejection fraction (LVEF), has important limitations. LVEF is limited by subjective interpretation which reduces accuracy and reproducibility, and LVEF assesses global function without characterizing regional myocardial abnormalities. An alternative objective echocardiographic measure of myocardial function is thus needed. Myocardial deformation analysis, which performs quantitative assessment of global and regional myocardial function, may be useful for perioperative care of surgical patients. Myocardial deformation analysis evaluates left ventricular mechanics by quantifying strain and strain rate. Strain describes percent change in myocardial length in the longitudinal (from base to apex) and circumferential (encircling the short-axis of the ventricle) direction and change in thickness in the radial direction. Segmental strain describes regional myocardial function. Strain is a negative number when the ventricle shortens longitudinally or circumferentially and is positive with radial thickening. Reference values for normal longitudinal strain from a recent meta-analysis using transthoracic echocardiography are (mean ± SD) −19.7 ± 0.4%, while radial and circumferential strain are 47.3 ± 1.9 and −23.3 ± 0.7%, respectively. The speed of myocardial deformation is also important and is characterized by strain rate. Longitudinal systolic strain rate in healthy subjects averages −1.10 ± 0.16 sec−1. Assessment of myocardial deformation requires consideration of both strain (change in deformation), which correlates with LVEF, and strain rate (speed of deformation), which correlates with rate of rise of left ventricular pressure (dP/dt). Myocardial deformation analysis also evaluates ventricular relaxation, twist, and untwist, providing new and noninvasive methods to

Bialgebra cohomology, deformations, and quantum groups.

PubMed Central

Gerstenhaber, M; Schack, S D

1990-01-01

We introduce cohomology and deformation theories for a bialgebra A (over a commutative unital ring k) such that the second cohomology group is the space of infinitesimal deformations. Our theory gives a natural identification between the underlying k-modules of the original and the deformed bialgebra. Certain explicit deformation formulas are given for the construction of quantum groups--i.e., Hopf algebras that are neither commutative nor cocommutative (whether or not they arise from quantum Yang-Baxter operators). These formulas yield, in particular, all GLq(n) and SLq(n) as deformations of GL(n) and SL(n). Using a Hodge decomposition of the underlying cochain complex, we compute our cohomology for GL(n). With this, we show that every deformation of GL(n) is equivalent to one in which the comultiplication is unchanged, not merely on elements of degree one but on all elements (settling in the strongest way a decade-old conjecture) and in which the quantum determinant, as an element of the underlying k-module, is identical with the usual one. PMID:11607053

Helium release during shale deformation: Experimental validation

DOE PAGES

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

2016-07-01

This paper 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 measuredmore » 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.« less

Deformed Palmprint Matching Based on Stable Regions.

PubMed

Wu, Xiangqian; Zhao, Qiushi

2015-12-01

Palmprint recognition (PR) is an effective technology for personal recognition. A main problem, which deteriorates the performance of PR, is the deformations of palmprint images. This problem becomes more severe on contactless occasions, in which images are acquired without any guiding mechanisms, and hence critically limits the applications of PR. To solve the deformation problems, in this paper, a model for non-linearly deformed palmprint matching is derived by approximating non-linear deformed palmprint images with piecewise-linear deformed stable regions. Based on this model, a novel approach for deformed palmprint matching, named key point-based block growing (KPBG), is proposed. In KPBG, an iterative M-estimator sample consensus algorithm based on scale invariant feature transform features is devised to compute piecewise-linear transformations to approximate the non-linear deformations of palmprints, and then, the stable regions complying with the linear transformations are decided using a block growing algorithm. Palmprint feature extraction and matching are performed over these stable regions to compute matching scores for decision. Experiments on several public palmprint databases show that the proposed models and the KPBG approach can effectively solve the deformation problem in palmprint verification and outperform the state-of-the-art methods.

Phase space deformations in phantom cosmology

NASA Astrophysics Data System (ADS)

López, J. L.; Sabido, M.; Yee-Romero, C.

2018-03-01

We discuss the physical consequences of general phase space deformations on the minisuperspace of phantom cosmology. Based on the principle of physically equivalent descriptions in the deformed theory, we investigate for what values of the deformation parameters the arising descriptions are physically equivalent. We also construct and solve the quantum model and derive the semiclassical dynamics.

Deformation Theory and Physics Model Building

NASA Astrophysics Data System (ADS)

Sternheimer, Daniel

2006-08-01

The mathematical theory of deformations has proved to be a powerful tool in modeling physical reality. We start with a short historical and philosophical review of the context and concentrate this rapid presentation on a few interrelated directions where deformation theory is essential in bringing a new framework - which has then to be developed using adapted tools, some of which come from the deformation aspect. Minkowskian space-time can be deformed into Anti de Sitter, where massless particles become composite (also dynamically): this opens new perspectives in particle physics, at least at the electroweak level, including prediction of new mesons. Nonlinear group representations and covariant field equations, coming from interactions, can be viewed as some deformation of their linear (free) part: recognizing this fact can provide a good framework for treating problems in this area, in particular global solutions. Last but not least, (algebras associated with) classical mechanics (and field theory) on a Poisson phase space can be deformed to (algebras associated with) quantum mechanics (and quantum field theory). That is now a frontier domain in mathematics and theoretical physics called deformation quantization, with multiple ramifications, avatars and connections in both mathematics and physics. These include representation theory, quantum groups (when considering Hopf algebras instead of associative or Lie algebras), noncommutative geometry and manifolds, algebraic geometry, number theory, and of course what is regrouped under the name of M-theory. We shall here look at these from the unifying point of view of deformation theory and refer to a limited number of papers as a starting point for further study.

Deformation of Reservoir Sandstones by Elastic versus Inelastic Deformation Mechanisms

NASA Astrophysics Data System (ADS)

Pijnenburg, R.; Verberne, B. A.; Hangx, S.; Spiers, C. J.

2016-12-01

Hydrocarbon or groundwater production from sandstone reservoirs can result in surface subsidence and induced seismicity. Subsidence results from combined elastic and inelastic compaction of the reservoir due to a change in the effective stress state upon fluid extraction. The magnitude of elastic compaction can be accurately described using poroelasticity theory. However inelastic or time-dependent compaction is poorly constrained. Specifically, the underlying microphysical processes controlling sandstone compaction remain poorly understood. We use sandstones recovered by the field operator (NAM) from the Slochteren gas reservoir (Groningen, NE Netherlands) to study the importance of elastic versus inelastic deformation processes upon simulated pore pressure depletion. We conducted conventional triaxial tests under true in-situ conditions of pressure and temperature. To investigate the effect of applied differential stress (σ1 - σ3 = 0 - 50 MPa) and initial sample porosity (φi = 12 - 24%) on instantaneous and time-dependent inelastic deformation, we imposed multiple stages of axial loading and relaxation. The results show that inelastic strain develops at all stages of loading, and that its magnitude increases with increasing value of differential stress and initial porosity. The stress sensitivity of the axial creep strain rate and microstructural evidence suggest that inelastic compaction is controlled by a combination of intergranular slip and intragranular cracking. Intragranular cracking is shown to be more pervasive with increasing values of initial porosity. The results are consistent with a conceptual microphysical model, involving deformation by poro-elasticity combined with intergranular sliding and grain contact failure. This model aims to predict sandstone deformation behavior for a wide range of stress conditions.

W.E.B. Du Bois and Caste Education: Racial Capitalist Schooling from Reconstruction to Jim Crow

ERIC Educational Resources Information Center

Pierce, Clayton

2017-01-01

This essay provides the first account and examination of caste education in the work of W.E.B. Du Bois. In so doing, I argue that caste education plays a central role in realizing the political and social goals of racial capitalist society for Du Bois. Using Du Bois's caste analytic, I take up and articulate three biopolitical governing strategies…

Effect of deformation ratios on grain alignment and magnetic properties of hot pressing/hot deformation Nd-Fe-B magnets

NASA Astrophysics Data System (ADS)

Guo, Zhaohui; Li, Mengyu; Wang, Junming; Jing, Zheng; Yue, Ming; Zhu, Minggang; Li, Wei

2018-05-01

The magnetic properties, microstructure and orientation degrees of hot pressing magnet and hot deformation Nd-Fe-B magnets with different deformation ratios have been investigated in this paper. The remanence (Br) and maximum magnetic energy product ((BH)max) were enhanced gradually with the deformation ratio increasing from 0% to 70%, whereas the coercivity (HCj) decreased. The scanning electron microscopy (SEM) images of fractured surfaces parallel to the pressure direction during hot deformation show that the grains tend to extend perpendicularly to the c-axes of Nd2Fe14B grains under the pressure, and the aspect ratios of the grains increase with the increase of deformation ratio. Besides, the compression stress induces the long axis of grains to rotate and the angle (θ) between c-axis and pressure direction decreases. The X-ray diffraction (XRD) patterns reveal that orientation degree improves with the increase of deformation ratio, agreeing well with the SEM results. The hot deformation magnet with a deformation ratio of 70% has the best Br and (BH)max, and the magnetic properties are as followed: Br=1.40 T, HCj=10.73 kOe, (BH)max=42.30 MGOe.

Anisotropic Ripple Deformation in Phosphorene.

PubMed

Kou, Liangzhi; Ma, Yandong; Smith, Sean C; Chen, Changfeng

2015-05-07

Two-dimensional materials tend to become crumpled according to the Mermin-Wagner theorem, and the resulting ripple deformation may significantly influence electronic properties as observed in graphene and MoS2. Here, we unveil by first-principles calculations a new, highly anisotropic ripple pattern in phosphorene, a monolayer black phosphorus, where compression-induced ripple deformation occurs only along the zigzag direction in the strain range up to 10%, but not the armchair direction. This direction-selective ripple deformation mode in phosphorene stems from its puckered structure with coupled hinge-like bonding configurations and the resulting anisotropic Poisson ratio. We also construct an analytical model using classical elasticity theory for ripple deformation in phosphorene under arbitrary strain. The present results offer new insights into the mechanisms governing the structural and electronic properties of phosphorene crucial to its device applications.

Expression, purification, and characterization of almond (Prunus dulcis) allergen Pru du 4.

PubMed

Zhang, Yuzhu; Du, Wen-Xian; Fregevu, Cécile; Kothary, Mahendra H; Harden, Leslie; McHugh, Tara H

2014-12-31

Biochemical characterizations of food allergens are required for understanding the allergenicity of food allergens. Such studies require a relatively large amount of highly purified allergens. The level of Pru du 4 in almond is low, and its expression in a soluble form in Escherichia coli required an expression tag. An MBP tag was used to enhance its expression and solubility. Sumo was used for the first time as a peptidase recognition site. The expression tag was removed with a sumo protease, and the resulting wild-type Pru du 4 was purified chromatographically. The stability of the allergen was investigated with chemical denaturation. The Gibbs free energy of Pru du 4 folding-unfolding transition was determined to be 5.4 ± 0.7 kcal/mol.

Deformation modes in an Icelandic basalt: From brittle failure to localized deformation bands

NASA Astrophysics Data System (ADS)

Adelinet, M.; Fortin, J.; Schubnel, A.; Guéguen, Y.

2013-04-01

According to the stress state, deformation mode observed in rocks may be very different. Even in the brittle part of the crust a differential stress can induce shear failure but also localized compacting deformation, such as compaction bands in porous sedimentary rocks. The mode of deformation controls many hydrodynamic factors, such as permeability and porosity. We investigate in this paper two different modes of deformation in an Icelandic basalt by using laboratory seismological tools (elastic waves and acoustic emissions) and microstructural observations. First of all, we show that at low effective confining pressure (Peff = 5 MPa) an axial loading induces a shear failure in the basalt with an angle of about 30° with respect to the main stress direction. On the contrary, at high effective confining pressure (Peff ≥ 75 MPa and more) an increase of the axial stress induces a localization of the deformation in the form of subhorizontal bands again with respect to the main stress direction. In this second regime, focal mechanisms of the acoustic emissions reveal an important number of compression events suggesting pore collapse mechanisms. Microstructural observations confirm this assumption. Similar compaction structures are usually obtained for porous sedimentary rocks (20-25%). However, the investigated basalt has an initial total porosity of only about 10% so that compaction structures were not expected. The pore size and the ratio of pore to grain size are likely to be key factors for the particular observed mechanical behavior.

Nouvelles approches en theorie du champ moyen dynamique: le cas du pouvoir thermoelectrique et celui de l'effet orbital d'un champ magnetique

NASA Astrophysics Data System (ADS)

Arsenault, Louis-Francois

Les applications reliees a la generation d'energie motivent la recherche de materiaux ayant un fort pouvoir thermoelectrique (S). De plus, S nous renseigne sur certaines proprietes fondamentales des materiaux, comme, par exemple, la transition entre l'etat coherent et incoherent des quasi-particules lorsque la temperature augmente. Empiriquement, la presence de fortes interactions electron-electron peut mener a un pouvoir thermoelectrique geant. Nous avons donc etudie le modele le plus simple qui tient compte de ces fortes interactions, le modele de Hubbard. La theorie du champ moyen dynamique (DMFT) est tout indiquee dans ce cas. Nous nous sommes concentres sur un systeme tridimensionnel (3d) cubique a face centree (fcc), et ce, pour plusieurs raisons. A) Ce type de cristal est tres commun dans la nature. B) La DMFT donne de tres bons resultats en 3d et donc ce choix sert aussi de preuve de principe de la methode. C) Finalement, a cause de la frustration electronique intrinseque au fcc, celui-ci ne presente pas de symetrie particule-trou, ce qui est tres favorable a l'apparition d'une grande valeur de S. Ce travail demontre que lorsque le materiau est un isolant a demi-remplissage a cause des fortes interactions (isolant de Mott), il est possible d'obtenir de grands pouvoirs thermoelectriques en le dopant legerement. C'est un resultat pratique important. Du point de vue methodologique, nous avons montre comment la limite de frequence infinie de S et l'approche dite de Kelvin, qui considere la limite de frequence nulle avant la limite thermodynamique pour S, donnent des estimations fiables de la vraie limite continue (DC) dans les domaines de temperature appropriee. Ces deux approches facilitent grandement les calculs en court-circuit ant la necessite de recourir a de problematiques prolongements analytiques. Nous avons trouve que la methode de calcul a frequence infinie fonctionne bien lorsque les echelles d'energie sont relativement faibles. En d'autres termes

Mesure de haute resolution de la fonction de distribution radiale du silicium amorphe pur

NASA Astrophysics Data System (ADS)

Laaziri, Khalid

1999-11-01

Cette these porte sur l'etude de la structure du silicium amorphe prepare par irradiation ionique. Elle presente des mesures de diffraction de rayons X sur de la poudre de silicium cristallin, du silicium amorphe relaxe et non relaxe, ainsi que tous les developpements mathematiques et physiques necessaires pour extraire la fonction de distribution radiale correspondant a chaque echantillon. Au Chapitre I, nous presentons une methode de fabrication de membranes minces de silicium amorphe pur. Il y a deux etapes majeures lors du processus de fabrication: l'implantation ionique, afin de creer une couche amorphe de plusieurs microns et l'attaque chimique, pour enlever le reste du materiau cristallin. Nous avons caracterise premierement les membranes de silicium amorphe par spectroscopie Raman pour verifier qu'il ne reste plus de trace de materiau cristallin dans les films amorphes. Une deuxieme caracterisation par detection de recul elastique (ERD-TOF) sur ces memes membranes a montre qu'il y a moins de 0.1% atomique de contaminants tels que l'oxygene, le carbone, et l'hydrogene. Au Chapitre II, nous proposons une nouvelle methode de correction de la contribution inelastique "Compton" des spectres de diffusion totale afin d'extraire les pics de diffusion elastique, responsable de la diffraction de Bragg. L'article presente tout d'abord une description simplifiee d'une theorie sur la diffusion inelastique dite "Impulse Approximation" (IA) qui permet de calculer des profils de Compton en fonction de l'energie et de l'angle de diffusion 2theta. Ces profils sont utilises comme fonction de lissage de la diffusion Compton experimentale. Pour lisser les pics de diffusion elastique, nous avons utilise une fonction pic de nature asymetrique. Aux Chapitre III, nous exposons de maniere detaillee les resultats des experiences de diffraction de rayons X sur les membranes de silicium amorphe et la poudre de silicium cristallin que nous avons preparees. Nous abordons aussi les

DuSable High School Program Flourishes.

ERIC Educational Resources Information Center

Graff, Pat

1995-01-01

Describes the fall and rise of the Panther Press, the scholastic newspaper of the DuSable High School in Chicago. States that despite being located in the midst of public housing projects, the school's newspaper is thriving where others in similar circumstances have failed. Describes how the school's principal and an advisor revitalized and…

Prejudice: From Allport to DuBois.

ERIC Educational Resources Information Center

Gaines, Stanley O., Jr.; Reed, Edward S.

1995-01-01

Examines the differences between Gordon Allport's and W. E. B. DuBois's theories on the origins of prejudice and the impact of discrimination on the personality and social development of blacks. The article argues that prejudice is a historically developed process, not a universal feature of human psychology. Implications for U.S. race relations…

T -folds from Yang-Baxter deformations

NASA Astrophysics Data System (ADS)

Fernández-Melgarejo, José J.; Sakamoto, Jun-ichi; Sakatani, Yuho; Yoshida, Kentaroh

2017-12-01

Yang-Baxter (YB) deformations of type IIB string theory have been well studied from the viewpoint of classical integrability. Most of the works, however, are focused upon the local structure of the deformed geometries and the global structure still remains unclear. In this work, we reveal a non-geometric aspect of YB-deformed backgrounds as T -fold by explicitly showing the associated O( D, D; ℤ) T -duality monodromy. In particular, the appearance of an extra vector field in the generalized supergravity equations (GSE) leads to the non-geometric Q-flux. In addition, we study a particular solution of GSE that is obtained by a non-Abelian T-duality but cannot be expressed as a homogeneous YB deformation, and show that it can also be regarded as a T -fold. This result indicates that solutions of GSE should be non-geometric quite in general beyond the YB deformation.

Accidental degeneracies in nonlinear quantum deformed systems

NASA Astrophysics Data System (ADS)

Aleixo, A. N. F.; Balantekin, A. B.

2011-09-01

We construct a multi-parameter nonlinear deformed algebra for quantum confined systems that includes many other deformed models as particular cases. We demonstrate that such systems exhibit the property of accidental pairwise energy level degeneracies. We also study, as a special case of our multi-parameter deformation formalism, the extension of the Tamm-Dancoff cutoff deformed oscillator and the occurrence of accidental pairwise degeneracy in the energy levels of the deformed system. As an application, we discuss the case of a trigonometric Rosen-Morse potential, which is successfully used in models for quantum confined systems, ranging from electrons in quantum dots to quarks in hadrons.

Instrumentation and fusion for congenital spine deformities.

PubMed

Hedequist, Daniel J

2009-08-01

A retrospective clinical review. To review the use of modern instrumentation of the spine for congenital spinal deformities. Spinal instrumentation has evolved since the advent of the Harrington rod. There is a paucity of literature, which discusses the use of modern spinal instrumentation in congenital spine deformity cases. This review focuses on modern instrumentation techniques for congenital scoliosis and kyphosis. A systematic review was performed of the literature to discuss spinal implant use for congenital deformities. Spinal instrumentation may be safely and effectively used in cases of congenital spinal deformity. Spinal surgeons taking care of children with congenital spine deformities need to be trained in all aspects of modern spinal instrumentation.

Anisotropic ripple deformation in phosphorene

DOE PAGES

Kou, Liangzhi; Ma, Yandong; Smith, Sean C.; ...

2015-04-07

Here, two-dimensional materials tend to become crumpled according to the Mermin-Wagner theorem, and the resulting ripple deformation may significantly influence electronic properties as observed in graphene and MoS 2. Here, we unveil by first-principles calculations a new, highly anisotropic ripple pattern in phosphorene, a monolayer black phosphorus, where compression-induced ripple deformation occurs only along the zigzag direction in the strain range up to 10%, but not the armchair direction. This direction-selective ripple deformation mode in phosphorene stems from its puckered structure with coupled hinge-like bonding configurations and the resulting anisotropic Poisson ratio. We also construct an analytical model using classicalmore » elasticity theory for ripple deformation in phosphorene under arbitrary strain. The present results offer new insights into the mechanisms governing the structural and electronic properties of phosphorene crucial to its device applications.« less

Anisotropic ripple deformation in phosphorene

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kou, Liangzhi; Ma, Yandong; Smith, Sean C.

Here, two-dimensional materials tend to become crumpled according to the Mermin-Wagner theorem, and the resulting ripple deformation may significantly influence electronic properties as observed in graphene and MoS 2. Here, we unveil by first-principles calculations a new, highly anisotropic ripple pattern in phosphorene, a monolayer black phosphorus, where compression-induced ripple deformation occurs only along the zigzag direction in the strain range up to 10%, but not the armchair direction. This direction-selective ripple deformation mode in phosphorene stems from its puckered structure with coupled hinge-like bonding configurations and the resulting anisotropic Poisson ratio. We also construct an analytical model using classicalmore » elasticity theory for ripple deformation in phosphorene under arbitrary strain. The present results offer new insights into the mechanisms governing the structural and electronic properties of phosphorene crucial to its device applications.« less

Facteurs de risque cardiovasculaires au cours du lupus systémique

PubMed Central

Harzallah, Amel; Hajji, Mariem; Kaaroud, Hayet; Hamida, Fethi Ben; Abdallah, Taieb Ben

2015-01-01

Cette étude a pour objectif d’évaluer la fréquence des facteurs de risque cardiovasculaires au cours du lupus et de préciser leur prévalence. Etude rétrospective portant sur 250 patients ayant un lupus, diagnostiqué selon les critères de l'ACR, hospitalisés entre 1970 et 2013. Les données cliniques et para cliniques ont été recueillies à partir des observations médicales. Il s'agit de 228 femmes et 22 hommes d’âge moyen au diagnostic du lupus de 30, 32 ans (extrêmes: 16-69). La durée moyenne du suivi des patients était de 64 mois (extrêmes: 7 jours- 382mois). Quatre vingt dix patients (36%) étaient hypertendus, 74% avaient une hypercholestérolémie et 22% étaient diabétiques. Pour les autres facteurs de risque cardiovasculaire traditionnels, un âge > 50 ans a été retrouvé dans 40% des cas, le sexe masculin dans 8% des cas, l'obésité dans 76% des cas et le tabagisme dans 11% des cas. Les facteurs de risque surajoutés sont représentés par la présence des anticorps antiphospholipides (47% des cas), la néphropathie lupique (49% des cas), l'insuffisance rénale (42% des cas), la corticothérapie au long cours (74% des cas) et la chronicité de la maladie dans 35% des cas. Les complications cardiovasculaires retrouvées dans notre série étaient: les accidents vasculaires cérébraux (2%) et l'insuffisance coronarienne (5,6%). Devant l'importance du risque cardiovasculaire au cours du lupus, une surveillance rapprochée des facteurs de risque cardio-vasculaires semble primordiale chez les lupiques. PMID:27022427

From labyrinthine aplasia to otocyst deformity.

PubMed

Giesemann, Anja Maria; Goetz, Friedrich; Neuburger, Jürgen; Lenarz, Thomas; Lanfermann, Heinrich

2010-02-01

Inner ear malformations (IEMs) are rare and it is unusual to encounter the rarest of them, namely labyrinthine aplasia (LA) and otocyst deformity. They do, however, provide useful pointers as to the early embryonic development of the ear. LA is characterised as a complete absence of inner ear structures. While some common findings do emerge, a clear definition of the otocyst deformity does not exist. It is often confused with the common cavity first described by Edward Cock. Our purpose was to radiologically characterise LA and otocyst deformity. Retrospective analysis of CT and MRI data from four patients with LA or otocyst deformity. Middle and inner ear findings were categorised by two neuroradiologists. The bony carotid canal was found to be absent in all patients. Posterior located cystic structures were found in association with LA and otocyst deformity. In the most severe cases, only soft tissue was present at the medial border of the middle ear cavity. The individuals with otocyst deformity also had hypoplasia of the petrous apex bone. These cases demonstrate gradual changes in the two most severe IEMs. Clarification of terms was necessary and, based on these findings, we propose defining otocyst deformity as a cystic structure in place of the inner ear, with the cochlea, IAC and carotid canal absent. This condition needs to be differentiated from the common cavity described by Edward Cook. A clear definition of inner ear malformations is essential if outcomes following cochlear implantation are to be compared.

World heritage site - Bien du Patrimoine Mondial - Kluane/Wrangell-St. Elias/Glacier Bay/Tatshenshini-Alsek

USGS Publications Warehouse

Labay, Keith A.; Wilson, Frederic H.

2004-01-01

The four parks depicted on this map make up a single World Heritage Site that covers 24.3 million acres. Together, they comprise the largest internationally protected land-based ecosystem on the planet. The United Nations Educational, Scientific and Cultural Organization (UNESCO) established the World Heritage Program in 1972 for the identification and protection of the world?s irreplaceable natural and cultural resources. World Heritage Sites are important as storehouses of memory and evolution, as anchors for sustainable tourism and community, and as laboratories for the study and understanding of the earth and culture. This World Heritage Site protects the prominent mountain ranges of Kluane, Wrangell, Saint Elias, and Chugach. It includes many of the tallest peaks on the continent, the world's largest non-polar icefield, extensive glaciers, vital watersheds, and expanses of dramatic wilderness. [Les quatre parcs figurant sur cette carte ne constituent qu?un seul site du patrimoine mondial recouvrant plus de 99 millions de km2, ce qui en fait le plus grand ecosysteme terrestre protege par loi internationale. En 1972, L?UNESCO (l?organisation des Nations Unies pour les sciences, l'education et la culture) a etabli le programme du patrimoine mondial afin d?identifier et de proteger les ressources naturelles et culturelles irremplacables de notre plan?te. Si les sites du patrimoine mondial sont si importants c'est parce qu'ils representent a la fois des livres ouverts sur l?histoire de la Terre, le point de depart du tourisme durable et du developpement des collectivites, des laboratoires pour etudier et comprendre la nature et la culture. Ce site du patrimoine mondial assure la protection des chaines de montagnes de Kluane, Wrangell, Saint Elias, et Chugach. On y trouve plusieurs des plus hauts sommets du continent, le plus grand champ de glace non-polaire du monde, d?immenses glaciers, des bassins hydrologiques essentiels, et de la nature sauvage a perte de vue.

The level of detail required in a deformable phantom to accurately perform quality assurance of deformable image registration

NASA Astrophysics Data System (ADS)

Saenz, Daniel L.; Kim, Hojin; Chen, Josephine; Stathakis, Sotirios; Kirby, Neil

2016-09-01

The primary purpose of the study was to determine how detailed deformable image registration (DIR) phantoms need to adequately simulate human anatomy and accurately assess the quality of DIR algorithms. In particular, how many distinct tissues are required in a phantom to simulate complex human anatomy? Pelvis and head-and-neck patient CT images were used for this study as virtual phantoms. Two data sets from each site were analyzed. The virtual phantoms were warped to create two pairs consisting of undeformed and deformed images. Otsu’s method was employed to create additional segmented image pairs of n distinct soft tissue CT number ranges (fat, muscle, etc). A realistic noise image was added to each image. Deformations were applied in MIM Software (MIM) and Velocity deformable multi-pass (DMP) and compared with the known warping. Images with more simulated tissue levels exhibit more contrast, enabling more accurate results. Deformation error (magnitude of the vector difference between known and predicted deformation) was used as a metric to evaluate how many CT number gray levels are needed for a phantom to serve as a realistic patient proxy. Stabilization of the mean deformation error was reached by three soft tissue levels for Velocity DMP and MIM, though MIM exhibited a persisting difference in accuracy between the discrete images and the unprocessed image pair. A minimum detail of three levels allows a realistic patient proxy for use with Velocity and MIM deformation algorithms.

Aspects épidémiologiques des traumatismes du rachis: à propos de 139 cas

PubMed Central

Bemora, Joseph Synèse; Rakotondraibe, Willy Francis; Ramarokoto, Mijoro; Ratovondrainy, Willy; Andriamamonjy, Clément

2017-01-01

Les traumatismes du rachis représentent une des lésions les plus fréquemment observées, chez les victimes d’accidents de circulation, d’accident de sportifs, domestique et du travail. Il s’agissait d’une étude rétrospective de 3 ans portant sur 139 cas de traumatismes du rachis hospitalisés et pris en charge dans le service de neurochirurgie du CHUJRA Madagascar. A travers cette étude, 25,17% des traumatisés étaient entre 21 et 30 ans avec une nette prédominance masculine de 69,78% (sexe ratio 2,3). L’étiologie était dominéepar la chute dans 33,09% des cas avec des facteurs de risque dont prise d’alcool (8,63%). Le traumatisme entrait dans le cadre d’un polytraumatisme dont un traumatisme crânien dans 34,63%. Les patients étaient admis dans le service 1 à 5h après le traumatisme dans 31,65% en utilisant comme moyen de transport une voiture personnelle dans 36,69%. Pendant l’hospitalisation 20 patients ont signé une décharge et 6,34% des patients sont décédés. Les traumatismes du rachis posent un problème de santé publique avec une prise en charge lourde surtout pour les patients déficitaires à vie. Devant tout traumatisme du rachis, il faut rechercher systématiquement une lésion crânienne. PMID:28450995

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

NASA Astrophysics Data System (ADS)

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

2005-05-01

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

Association between Fatigue and Autistic Symptoms in Children with Cri du Chat Syndrome

ERIC Educational Resources Information Center

Claro, Anthony; Cornish, Kim; Gruber, Reut

2011-01-01

In the current study, the authors examined whether the fatigue level of children diagnosed with cri du chat syndrome was associated with the expression of autistic symptoms. Sixty-nine children with cri du chat syndrome were compared with 47 children with moderate to severe intellectual disabilities who did not differ on intellectual severity.…

Deformation Measurements of Smart Aerodynamic Surfaces

NASA Technical Reports Server (NTRS)

Fleming, Gary A.; Burner, Alpheus

2005-01-01

Video Model Deformation (VMD) and Projection Moire Interferometry (PMI) were used to acquire wind tunnel model deformation measurements of the Northrop Grumman-built Smart Wing tested in the NASA Langley Transonic Dynamics Tunnel. The F18-E/F planform Smart Wing was outfitted with embedded shape memory alloys to actuate a seamless trailing edge aileron and flap, and an embedded torque tube to generate wing twist. The VMD system was used to obtain highly accurate deformation measurements at three spanwise locations along the main body of the wing, and at spanwise locations on the flap and aileron. The PMI system was used to obtain full-field wing shape and deformation measurements over the entire wing lower surface. Although less accurate than the VMD system, the PMI system revealed deformations occurring between VMD target rows indistinguishable by VMD. This paper presents the VMD and PMI techniques and discusses their application in the Smart Wing test.

Cardiac fluid dynamics meets deformation imaging.

PubMed

Dal Ferro, Matteo; Stolfo, Davide; De Paris, Valerio; Lesizza, Pierluigi; Korcova, Renata; Collia, Dario; Tonti, Giovanni; Sinagra, Gianfranco; Pedrizzetti, Gianni

2018-02-20

Cardiac function is about creating and sustaining blood in motion. This is achieved through a proper sequence of myocardial deformation whose final goal is that of creating flow. Deformation imaging provided valuable contributions to understanding cardiac mechanics; more recently, several studies evidenced the existence of an intimate relationship between cardiac function and intra-ventricular fluid dynamics. This paper summarizes the recent advances in cardiac flow evaluations, highlighting its relationship with heart wall mechanics assessed through the newest techniques of deformation imaging and finally providing an opinion of the most promising clinical perspectives of this emerging field. It will be shown how fluid dynamics can integrate volumetric and deformation assessments to provide a further level of knowledge of cardiac mechanics.

A Deformable Atlas of the Laboratory Mouse

PubMed Central

Wang, Hongkai; Stout, David B.; Chatziioannou, Arion F.

2015-01-01

Purpose This paper presents a deformable mouse atlas of the laboratory mouse anatomy. This atlas is fully articulated and can be positioned into arbitrary body poses. The atlas can also adapt body weight by changing body length and fat amount. Procedures A training set of 103 micro-CT images was used to construct the atlas. A cage-based deformation method was applied to realize the articulated pose change. The weight-related body deformation was learned from the training set using a linear regression method. A conditional Gaussian model and thin-plate spline mapping were used to deform the internal organs following the changes of pose and weight. Results The atlas was deformed into different body poses and weights, and the deformation results were more realistic compared to the results achieved with other mouse atlases. The organ weights of this atlas matched well with the measurements of real mouse organ weights. This atlas can also be converted into voxelized images with labeled organs, pseudo CT images and tetrahedral mesh for phantom studies. Conclusions With the unique ability of articulated pose and weight changes, the deformable laboratory mouse atlas can become a valuable tool for preclinical image analysis. PMID:25049072

Macroscopic modelling of semisolid deformation for considering segregation bands induced by shear deformation

NASA Astrophysics Data System (ADS)

Morita, S.; Yasuda, H.; Nagira, T.; Gourlay, C. M.; Yoshiya, M.; Sugiyama, A.

2012-07-01

In-situ observation was carried out to observe deformation of semi-solid Fe-2mass%C steel with 65% solid and globular morphology by X-ray radiography. Deformation was predominantly controlled by the rearrangement of globules. The solid particles were pushed into each other and rearrangement caused lower solid fraction regions to form. On the basis of the observation, a macroscopic model that introduces a normal stress acting on the solid due to collisions and rearrangement is proposed. The solid particles are treated as a non-Newtonian fluid. The stiffness parameters, which characterize the flow of the solid, are introduced. Stability of semisolid to fluctuations in solid fraction during simple shear was analysed. Shear deformation can be stably localized in the semisolid with a certain solid fraction range. The model essentially reproduces band segregation formation.

14 CFR 23.305 - Strength and deformation.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Strength and deformation. 23.305 Section 23.305 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT..., permanent deformation. At any load up to limit loads, the deformation may not interfere with safe operation...

14 CFR 23.305 - Strength and deformation.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Strength and deformation. 23.305 Section 23.305 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT..., permanent deformation. At any load up to limit loads, the deformation may not interfere with safe operation...

A q-deformation of the Bogoliubov transformations

NASA Astrophysics Data System (ADS)

Arraut, Ivan; Segovia, Carlos

2018-02-01

An approach for q-deformed Bogoliubov transformations is presented. Assuming a left-right module action together with an *-operation and deformed commutation relations, we construct a q-deformation of the nonlinear Bogoliubov transformation. Finally, we introduce a Hopf structure when q is a root of unity.

Self-adjointness of deformed unbounded operators

DOE Office of Scientific and Technical Information (OSTI.GOV)

Much, Albert

2015-09-15

We consider deformations of unbounded operators by using the novel construction tool of warped convolutions. By using the Kato-Rellich theorem, we show that unbounded self-adjoint deformed operators are self-adjoint if they satisfy a certain condition. This condition proves itself to be necessary for the oscillatory integral to be well-defined. Moreover, different proofs are given for self-adjointness of deformed unbounded operators in the context of quantum mechanics and quantum field theory.

A Conversation with Lee Alvin DuBridge - Part I

NASA Astrophysics Data System (ADS)

Goodstein, Judith R.

Physicist Lee A. DuBridge became president of the California Institute of Technology in 1946. In this interview he recalls the immediate problems he faced, including his dealings with Robert A. Millikan, whom he replaced as chief administrator of the institute; institute financing and inadequate salaries. DuBridge also talks about the advent of federal support for peacetime science and Millikan's distaste for it; his close working relationship with Robert F. Bacher, who came to the institute in 1949 as chairman of the Division of Physics, Mathematics, and Astronomy; his recollections of the meteorologist Irving P. Krick, the physicist Alexander Goetz, and the chemist Linus Pauling; and his attempts to build up the Humanities Division.

14 CFR 27.305 - Strength and deformation.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Strength and deformation. 27.305 Section 27.305 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT... deformation. At any load up to limit loads, the deformation may not interfere with safe operation. (b) The...

14 CFR 27.305 - Strength and deformation.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Strength and deformation. 27.305 Section 27.305 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT... deformation. At any load up to limit loads, the deformation may not interfere with safe operation. (b) The...

FEM modeling of postseismic deformation of poroelastic material

NASA Astrophysics Data System (ADS)

Kawamoto, S.; Ito, T.; Hirahara, K.

2004-12-01

Following a large earthquake, postseismic deformation in the focal region has been observed by GPS, leveling measurements and the other geodetic measurements. To explain the postseismic deformation, researchers have proposed and well investigated two physical mechanisms of afterslip and viscoelastic relaxation. In some cases, however, there have been observed postseismic deformation which can not be explained by these mechanisms. Therefore, another mechanism has been proposed, where the crust is treated as "poroelastic material". This concept is called "poroelasticity". In this concept, postseismic deformation is caused by pore fluid flow due to the coseismic stress redistribution. We explored, therefore, the postseismic deformation due to pore fluid flow in a poroelastic material using finite element method (FEM), which can easily handle lateral variations of hydraulic diffusivity and elastic or plastic property. We used the FEM program 'CAMBIOT3D' originally developed by Geotech. Lab. Gunma University, Japan (2003). Because this program was developed for soil mechanics, we must have modified so as to calculate deformation due to earthquake faulting. We implemented the 'split node technique' (Melosh and Refsky, 1981) to calculate the coseismic deformation. In addition to this, we modified the program to calculate the deformation taking into account the Skempton's B. This coefficient B determines what fraction of the coseismic stress due to an earthquake is allotted to pore pressure. Without Skempton's B, coseismic pore pressure becomes too large and hence postseismic deformation is calculated too large. We evaluated the postseismic deformation in a poroelastic material to show that the poroelastic deformation is quite different from that of afterslip and viscoelastic relaxation models. In this presentation, we show the postseismic deformation due to pore fluids flow in a poroelastic material and the effect of Skempton's B. Especially, we discuss what different

Transient deformation from daily GPS displacement time series: postseismic deformation, ETS and evolving strain rates

NASA Astrophysics Data System (ADS)

Bock, Y.; Fang, P.; Moore, A. W.; Kedar, S.; Liu, Z.; Owen, S. E.; Glasscoe, M. T.

2016-12-01

Detection of time-dependent crustal deformation relies on the availability of accurate surface displacements, proper time series analysis to correct for secular motion, coseismic and non-tectonic instrument offsets, periodic signatures at different frequencies, and a realistic estimate of uncertainties for the parameters of interest. As part of the NASA Solid Earth Science ESDR System (SESES) project, daily displacement time series are estimated for about 2500 stations, focused on tectonic plate boundaries and having a global distribution for accessing the terrestrial reference frame. The "combined" time series are optimally estimated from independent JPL GIPSY and SIO GAMIT solutions, using a consistent set of input epoch-date coordinates and metadata. The longest time series began in 1992; more than 30% of the stations have experienced one or more of 35 major earthquakes with significant postseismic deformation. Here we present three examples of time-dependent deformation that have been detected in the SESES displacement time series. (1) Postseismic deformation is a fundamental time-dependent signal that indicates a viscoelastic response of the crust/mantle lithosphere, afterslip, or poroelastic effects at different spatial and temporal scales. It is critical to identify and estimate the extent of postseismic deformation in both space and time not only for insight into the crustal deformation and earthquake cycles and their underlying physical processes, but also to reveal other time-dependent signals. We report on our database of characterized postseismic motions using a principal component analysis to isolate different postseismic processes. (2) Starting with the SESES combined time series and applying a time-dependent Kalman filter, we examine episodic tremor and slow slip (ETS) in the Cascadia subduction zone. We report on subtle slip details, allowing investigation of the spatiotemporal relationship between slow slip transients and tremor and their

Videogrammetric Model Deformation Measurement Technique

NASA Technical Reports Server (NTRS)

Burner, A. W.; Liu, Tian-Shu

2001-01-01

The theory, methods, and applications of the videogrammetric model deformation (VMD) measurement technique used at NASA for wind tunnel testing are presented. The VMD technique, based on non-topographic photogrammetry, can determine static and dynamic aeroelastic deformation and attitude of a wind-tunnel model. Hardware of the system includes a video-rate CCD camera, a computer with an image acquisition frame grabber board, illumination lights, and retroreflective or painted targets on a wind tunnel model. Custom software includes routines for image acquisition, target-tracking/identification, target centroid calculation, camera calibration, and deformation calculations. Applications of the VMD technique at five large NASA wind tunnels are discussed.

Diagnostic et prévalence du syndrome métabolique chez les diabétiques suivis dans un contexte de ressources limitées: cas du Burkina-Faso

PubMed Central

Marceline, Yaméogo Téné; Issiaka, Sombié; Gilberte, Kyélem Carole; Nadège, Rouamba; Macaire, Ouédraogo Sampawindé; Arsène, Yaméogo Aimé; Djingri, Lankoandé; Apollinaire, Sawadogo; Joseph, Drabo Youssouf

2014-01-01

Introduction Les conséquences du syndrome métabolique impliquent son diagnostic effectif pour une prise en charge globale des comorbidités dépistées. Objectif: Déterminer la capacité à diagnostiquer le syndrome métabolique en routine, sa prévalence chez les diabétiques, leurs connaissances et pratiques vis-à-vis du risque cardio-métabolique. Méthodes Il s'est agi d'une étude transversale auprès de 388 diabétiques au CHU de Bobo-Dioulasso. Les critères de la fédération internationale du diabète (2009) ont été utilisés. Résultats l’âge moyen était de 53,5±13,5 ans, le sex ratio de 0,7. L'obésité abdominale était présente dans 61,9% des cas; L'HTA l’était dans 56,4% des cas. La prescription du bilan lipidique a été documentée dans 55,4% des cas pour le HDL et 56,2% pour les triglycérides pour un taux de réalisation de 49,3% et 62,9%. Le taux de dépistage des critères lipidiques était de 26,8%. Un taux de HDL bas a été noté dans 46 cas (43,4%) et une hypertriglycéridémie dans 24 cas (17,6%). In fine, la prévalence du syndrome métabolique était de 48,9% (n = 190). Seuls 27,4% savaient que d'autres facteurs de risque cardiovasculaire pouvaient être associés au diabète et seulement 6,7% pratiquaient une activité physique régulière. Conclusion Malgré la faible contribution du laboratoire, le syndrome métabolique est fréquent parmi nos diabétiques. Les patients sont peu sensibilisés sur le risque vasculaire et la pratique d'une activité physique régulière reste faible. Un programme d’éducation adaptée contribuerait à un meilleur dépistage et à une prise en charge optimale des cas. PMID:25932077

Dynamic Projection Mapping onto Deforming Non-Rigid Surface Using Deformable Dot Cluster Marker.

PubMed

Narita, Gaku; Watanabe, Yoshihiro; Ishikawa, Masatoshi

2017-03-01

Dynamic projection mapping for moving objects has attracted much attention in recent years. However, conventional approaches have faced some issues, such as the target objects being limited to rigid objects, and the limited moving speed of the targets. In this paper, we focus on dynamic projection mapping onto rapidly deforming non-rigid surfaces with a speed sufficiently high that a human does not perceive any misalignment between the target object and the projected images. In order to achieve such projection mapping, we need a high-speed technique for tracking non-rigid surfaces, which is still a challenging problem in the field of computer vision. We propose the Deformable Dot Cluster Marker (DDCM), a novel fiducial marker for high-speed tracking of non-rigid surfaces using a high-frame-rate camera. The DDCM has three performance advantages. First, it can be detected even when it is strongly deformed. Second, it realizes robust tracking even in the presence of external and self occlusions. Third, it allows millisecond-order computational speed. Using DDCM and a high-speed projector, we realized dynamic projection mapping onto a deformed sheet of paper and a T-shirt with a speed sufficiently high that the projected images appeared to be printed on the objects.

Correcting deformity in total knee arthroplasty: Techniques to avoid the release of collateral ligaments in severely deformed knees.

PubMed

Mullaji, A B; Shetty, G M

2016-01-01

Collateral ligament release is advocated in total knee arthroplasty (TKA) to deal with significant coronal plane deformities, but is also associated with significant disadvantages. We describe steps to avoid release of the collateral (superficial medial and lateral collateral) ligaments during TKA in severely deformed knees, while correcting deformity and balancing the knee. ©2016 The British Editorial Society of Bone & Joint Surgery.

Interfacial diffusion aided deformation during nanoindentation

DOE PAGES

Samanta, Amit; E., Weinan

2015-07-06

Nanoindentation is commonly used to quantify the mechanical response of material surfaces. Despite its widespread use, a detailed understanding of the deformation mechanisms responsible for plasticity during these experiments has remained elusive. Nanoindentation measurements often show stress values close to a material’s ideal strength which suggests that dislocation nucleation and subsequent dislocation activity dominates the deformation. However, low strain-rate exponents and small activation volumes have also been reported which indicates high temperature sensitivity of the deformation processes. Using an order parameter aided temperature accelerated sampling technique called adiabatic free energy dynamics [J. B. Abrams and M. E. Tuckerman, J. Phys.more » Chem. B, 112, 15742 (2008)], and molecular dynamics we have probed the diffusive mode of deformation during nanoindentation. Localized processes such as surface vacancy and ad-atom pair formation, vacancy diffusion are found to play an important role during indentation. Furthermore, our analysis suggests a change in the dominant deformation mode from dislocation mediated plasticity to diffusional flow at high temperatures, slow indentation rates and small indenter tip radii.« less

Prevalence of Autism Spectrum Phenomenology in Cornelia de Lange and Cri du Chat Syndromes

ERIC Educational Resources Information Center

Moss, Joanna F.; Oliver, Chris; Berg, Katy; Kaur, Gurmeash; Jephcott, Lesley; Cornish, Kim

2008-01-01

Autism spectrum disorder characteristics have not been evaluated in Cornelia de Lange and Cri du Chat syndromes using robust assessments. The Autism Diagnostic Observation Schedule and Social Communication Questionnaire were administered to 34 participants with Cornelia de Lange syndrome and a comparison group of 23 participants with Cri du Chat…

Deformable Organic Nanowire Field-Effect Transistors.

PubMed

Lee, Yeongjun; Oh, Jin Young; Kim, Taeho Roy; Gu, Xiaodan; Kim, Yeongin; Wang, Ging-Ji Nathan; Wu, Hung-Chin; Pfattner, Raphael; To, John W F; Katsumata, Toru; Son, Donghee; Kang, Jiheong; Matthews, James R; Niu, Weijun; He, Mingqian; Sinclair, Robert; Cui, Yi; Tok, Jeffery B-H; Lee, Tae-Woo; Bao, Zhenan

2018-02-01

Deformable electronic devices that are impervious to mechanical influence when mounted on surfaces of dynamically changing soft matters have great potential for next-generation implantable bioelectronic devices. Here, deformable field-effect transistors (FETs) composed of single organic nanowires (NWs) as the semiconductor are presented. The NWs are composed of fused thiophene diketopyrrolopyrrole based polymer semiconductor and high-molecular-weight polyethylene oxide as both the molecular binder and deformability enhancer. The obtained transistors show high field-effect mobility >8 cm 2 V -1 s -1 with poly(vinylidenefluoride-co-trifluoroethylene) polymer dielectric and can easily be deformed by applied strains (both 100% tensile and compressive strains). The electrical reliability and mechanical durability of the NWs can be significantly enhanced by forming serpentine-like structures of the NWs. Remarkably, the fully deformable NW FETs withstand 3D volume changes (>1700% and reverting back to original state) of a rubber balloon with constant current output, on the surface of which it is attached. The deformable transistors can robustly operate without noticeable degradation on a mechanically dynamic soft matter surface, e.g., a pulsating balloon (pulse rate: 40 min -1 (0.67 Hz) and 40% volume expansion) that mimics a beating heart, which underscores its potential for future biomedical applications. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Deformation compatibility in a single crystalline Ni superalloy

PubMed Central

Zhang, Tiantian; Dunne, Fionn P. E.

2016-01-01

Deformation in materials is often complex and requires rigorous understanding to predict engineering component lifetime. Experimental understanding of deformation requires utilization of advanced characterization techniques, such as high spatial resolution digital image correlation (HR-DIC) and high angular resolution electron backscatter diffraction (HR-EBSD), combined with clear interpretation of their results to understand how a material has deformed. In this study, we use HR-DIC and HR-EBSD to explore the mechanical behaviour of a single-crystal nickel alloy and to highlight opportunities to understand the complete deformations state in materials. Coupling of HR-DIC and HR-EBSD enables us to precisely focus on the extent which we can access the deformation gradient, F, in its entirety and uncouple contributions from elastic deformation gradients, slip and rigid body rotations. Our results show a clear demonstration of the capabilities of these techniques, found within our experimental toolbox, to underpin fundamental mechanistic studies of deformation in polycrystalline materials and the role of microstructure. PMID:26997901

Nanolaminate deformable mirrors

DOEpatents

Papavasiliou, Alexandros P.; Olivier, Scot S.

2009-04-14

A deformable mirror formed out of two layers of a nanolaminate foil attached to a stiff substrate is introduced. Deformation is provided by an electrostatic force between two of the layers. The internal stiffness of the structure allows for high-spatial-frequency shapes. The nanolaminate foil of the present invention allows for a high-quality mirror surface. The device achieves high precision in the vertical direction by using foils with accurately controlled thicknesses, but does not require high precision in the lateral dimensions, allowing such mirrors to be fabricated using crude lithography techniques. Such techniques allow structures up to about the meter scale to be fabricated.

[Herbal textual research of common Mongolian medicine "Du Ge Mo Nong"].

PubMed

Xi, Jie; Zhong, Hua-Rong; Wucharila-Tu; Buhe Bater; Li, Hui-Hu; Zhong, Guo-Yue

2016-11-01

This study is aimed to provide the source for clinical medication by clarifing the common base of Mongolia medicinal materials "Du Ge Mo Nong". In this paper literature research and plant taxonomy method were adopted combined with investigation of the markets and clinical use status to clarify the origin of common traditional Mongolian medicine "Du Ge Mo Nong". The results showed that the Mongolian medicine "Du Ge Mo Nong" and Tibetan medicine "Du Mu Niu" were the same crude drug and originated from the seeds of Holarrhena antidysenteriaca of family Apocynaceae in earliest time. In Mongolian medicine clinic, the seed of Cynanchum thesioides of family Asclepiadaceae and the fruit of Forsythia suspense of family Oleaceae was used respectively about 18 century and recent time, as the substitutes of H. antidysenteriaca. In present standards on Mongolian material medicine, C. thesioides is including only, and H. antidysenterica is not used almost. In Tibetan medicine clinic, H. antidysenterica is being used so far. But there are various substitutes including the seeds, fruits or grass of many species classified to family Apocynaceae, Asclepiadaceae and Onagraceae from ancient time to the present, and C. forrestii and C. komarovii may be used at present. It's necessary to strengthen the arrangement on Mongolian medicine's varieties by the multidisciplinary methods including literature research, investigation of resources and the use state, and comparison of active substances and biological activities between the different substitutes,and so on. Copyright© by the Chinese Pharmaceutical Association.

Localized crustal deformation in the Godavari failed rift, India

NASA Astrophysics Data System (ADS)

Mahesh, P.; Gahalaut, V. K.; Catherine, J. K.; Ambikapathy, A.; Kundu, Bhaskar; Bansal, Amit; Chadha, R. K.; Narsaiah, M.

2012-06-01

Six years of GPS measurements of crustal deformation in the Godavari failed rift (GFR) of stable India plate suggest very localized deformation. Elsewhere, all along the GFR the deformation is very low (<1.5 mm/yr). Localized deformation (up to 3.3±0.5 mm/yr) at least at two sites, implying compression on steep faults located on the southern margin of the GFR, is coincident with the region characterized by high level low-magnitude seismicity of past six years and implies strain accumulation for future moderate to strong magnitude earthquake in the region. The localized deformation is consistent with the view about deformation in such regions where seismicity migrates and deformation rate changes with time.

Riccati Parametric Deformations of the Cornu Spiral

NASA Astrophysics Data System (ADS)

Rosu, Haret C.; Mancas, Stefan C.; Flores-Garduño, Elizabeth

2018-06-01

In this article, a parametric deformation of the Cornu spiral is introduced. The parameter is an integration constant which appears in the general solution of the Riccati equation and is related to the Fresnel integrals. The Argand plots of the deformed spirals are presented and a supersymmetric (Darboux) structure of the deformation is revealed through the factorization approach.

Quantification of abdominal aortic deformation after EVAR

NASA Astrophysics Data System (ADS)

Demirci, Stefanie; Manstad-Hulaas, Frode; Navab, Nassir

2009-02-01

Quantification of abdominal aortic deformation is an important requirement for the evaluation of endovascular stenting procedures and the further refinement of stent graft design. During endovascular aortic repair (EVAR) treatment, the aortic shape is subject to severe deformation that is imposed by medical instruments such as guide wires, catheters, and, the stent graft. This deformation can affect the flow characteristics and morphology of the aorta which have been shown to be elicitors for stent graft failures and be reason for reappearance of aneurysms. We present a method for quantifying the deformation of an aneurysmatic aorta imposed by an inserted stent graft device. The outline of the procedure includes initial rigid alignment of the two abdominal scans, segmentation of abdominal vessel trees, and automatic reduction of their centerline structures to one specified region of interest around the aorta. This is accomplished by preprocessing and remodeling of the pre- and postoperative aortic shapes before performing a non-rigid registration. We further narrow the resulting displacement fields to only include local non-rigid deformation and therefore, eliminate all remaining global rigid transformations. Finally, deformations for specified locations can be calculated from the resulting displacement fields. In order to evaluate our method, experiments for the extraction of aortic deformation fields are conducted on 15 patient datasets from endovascular aortic repair (EVAR) treatment. A visual assessment of the registration results and evaluation of the usage of deformation quantification were performed by two vascular surgeons and one interventional radiologist who are all experts in EVAR procedures.

Epidémiologie et prise en charge des infections du per-partum à la maternité du centre hospitalier départemental de l'Ouémé-Plateau au Bénin

PubMed Central

Saizonou, Jacques; Ouédraogo, Laurent; Paraiso, Moussiliou Noël; Ayélo, Paul; Kpozèhouen, Alphonse; Daraté, René; Traoré, Esther

2014-01-01

Introduction La présente étude avait pour objectif de mesurer l'ampleur des infections du per-partum à la maternité du Centre Hospitalier Départemental de l'Ouémé-Plateau d'analyser les conditions de survenue et de prise en charge dans la perspective de l'amélioration des soins et services maternels et néonataux. Méthodes Une étude descriptive et analytique a été conduite de Août 2009 à Février 2010 et a impliqué 110 mères victimes d'infections du per-partum; elles ont été soumises à un questionnaire durant tout leur séjour hospitalier; des observations des pratiques de prise en charge des prestataires de soins ont été menées et des registres et autres supports de données sanitaires ont été exploités. L'analyse des données a été effectuée à l'aide du logiciel Epi Info 6.4 dans sa version française. Résultats L'incidence des infections du per-partum était de 5,9 pour 100 accouchements (110/ 1875); les types d'infections les plus incriminés étaient les endométrites (27,3%), les chorioamniotites (18,2%), les infections du site opératoire (12,7%) et les infections urinaires (2,7%). Les examens cliniques ont été relativement acceptables. En revanche, les examens biologiques ont été très insuffisants expliquant l'imprécision importante au niveau des diagnostics. L'antibiothérapie a été instaurée systématiquement. Le taux de mortinaissance était de 25,6% et les enfants de petit poids représentaient 23,2%. Conclusion L'incidence des infections du per-partum dans la présente étude était assez élevée. Des efforts de préventions et de dépistage de ces infections sont nécessaire afin d'améliorer la qualité des soins PMID:25120854

Application of Quaternions for Mesh Deformation

NASA Technical Reports Server (NTRS)

Samareh, Jamshid A.

2002-01-01

A new three-dimensional mesh deformation algorithm, based on quaternion algebra, is introduced. A brief overview of quaternion algebra is provided, along with some preliminary results for two-dimensional structured and unstructured viscous mesh deformation.

Meshless Modeling of Deformable Shapes and their Motion

PubMed Central

Adams, Bart; Ovsjanikov, Maks; Wand, Michael; Seidel, Hans-Peter; Guibas, Leonidas J.

2010-01-01

We present a new framework for interactive shape deformation modeling and key frame interpolation based on a meshless finite element formulation. Starting from a coarse nodal sampling of an object’s volume, we formulate rigidity and volume preservation constraints that are enforced to yield realistic shape deformations at interactive frame rates. Additionally, by specifying key frame poses of the deforming shape and optimizing the nodal displacements while targeting smooth interpolated motion, our algorithm extends to a motion planning framework for deformable objects. This allows reconstructing smooth and plausible deformable shape trajectories in the presence of possibly moving obstacles. The presented results illustrate that our framework can handle complex shapes at interactive rates and hence is a valuable tool for animators to realistically and efficiently model and interpolate deforming 3D shapes. PMID:24839614

Highly deformable bones: unusual deformation mechanisms of seahorse armor.

PubMed

Porter, Michael M; Novitskaya, Ekaterina; Castro-Ceseña, Ana Bertha; Meyers, Marc A; McKittrick, Joanna

2013-06-01

Multifunctional materials and devices found in nature serve as inspiration for advanced synthetic materials, structures and robotics. Here, we elucidate the architecture and unusual deformation mechanisms of seahorse tails that provide prehension as well as protection against predators. The seahorse tail is composed of subdermal bony plates arranged in articulating ring-like segments that overlap for controlled ventral bending and twisting. The bony plates are highly deformable materials designed to slide past one another and buckle when compressed. This complex plate and segment motion, along with the unique hardness distribution and structural hierarchy of each plate, provide seahorses with joint flexibility while shielding them against impact and crushing. Mimicking seahorse armor may lead to novel bio-inspired technologies, such as flexible armor, fracture-resistant structures or prehensile robotics. Copyright © 2013 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

W. E. B. Du Bois at the center: from science, civil rights movement, to Black Lives Matter.

PubMed

Morris, Aldon

2017-03-01

I am honoured to present the 2016 British Journal of Sociology Annual Lecture at the London School of Economics. My lecture is based on ideas derived from my new book, The Scholar Denied: W.E.B. Du Bois and the Birth of Modern Sociology. In this essay I make three arguments. First, W.E.B. Du Bois and his Atlanta School of Sociology pioneered scientific sociology in the United States. Second, Du Bois pioneered a public sociology that creatively combined sociology and activism. Finally, Du Bois pioneered a politically engaged social science relevant for contemporary political struggles including the contemporary Black Lives Matter movement. © London School of Economics and Political Science 2017.

Deformation effect on spectral statistics of nuclei

NASA Astrophysics Data System (ADS)

Sabri, H.; Jalili Majarshin, A.

2018-02-01

In this study, we tried to get significant relations between the spectral statistics of atomic nuclei and their different degrees of deformations. To this aim, the empirical energy levels of 109 even-even nuclei in the 22 ≤ A ≤ 196 mass region are classified as their experimental and calculated quadrupole, octupole, hexadecapole and hexacontatetrapole deformations values and analyzed by random matrix theory. Our results show an obvious relation between the regularity of nuclei and strong quadrupole, hexadecapole and hexacontatetrapole deformations and but for nuclei that their octupole deformations are nonzero, we have observed a GOE-like statistics.

Adhesive interaction of elastically deformable spherical particles

NASA Astrophysics Data System (ADS)

D'yachenko, E. N.; Dueck, J. G.

2012-01-01

Two spherical particles that attract each other by van der Waals volume forces and can undergo deformation as a result of the attraction are considered. Small deformations of such particles can be described by the solution of the Hertz problem. The deformation of particles, in turn, alters the force of attraction between them. It has been established that the relationship between the adhesion and elasticity of the indicated particles is determined by the degree to which these particles deform and that the adhesion force acting between the particles depends on their elasticity, size, and the Hamaker constants.

Fluctuations of a q-deformed fermion gas

NASA Astrophysics Data System (ADS)

Zeng, Qijun; Ge, Jing; Luo, Yongsong

2018-05-01

The theory of q-deformed fermions is one of the theories of q-deformed oscillators. Within the framework of this theory and the traditional fluctuation theory, we investigate fluctuations of q-deformed fermion gas and obtain the expressions of fluctuations of the internal energy U, the particle number N and the correlation of fluctuations of the two physical quantities above. Further numerical calculation reveals that fluctuations of such a system have some interesting and particular features. We consider that this work may provide much insight into the theory of q fermions, and may also be helpful for the theory of q-deformed oscillators.

Les traces matérielles de la Carte du Ciel. Le cas des observatoires d'Alger et de Bordeaux.

NASA Astrophysics Data System (ADS)

Le Guet Tully, F.; Davoigneau, J.; Lamy, J.; de La Noë, J.; Rousseau, J.-M.; Sadsaoud, H.

2008-06-01

Le chapitre évoque les traces matérielles de la Carte du ciel subsistant dans les observatoires d'Alger et de Bordeaux. Les auteurs examinent d'abord l'opération d'inventaire du patrimoine astronomique entreprise à partir du milieu des années 1990. Ils examinent ensuite les éléments concrets constituant aujourd'hui le patrimoine de la Carte du Ciel : lunettes, abris, accessoires, laboratoires, réseaux, plaques de verre, registres, machines à mesurer les clichés, et cartes.

A multi-organ biomechanical model to analyze prostate deformation due to large deformation of the rectum

NASA Astrophysics Data System (ADS)

Brock, Kristy K.; Ménard, Cynthia; Hensel, Jennifer; Jaffray, David A.

2006-03-01

Magnetic resonance imaging (MRI) with an endorectal receiver coil (ERC) provides superior visualization of the prostate gland and its surrounding anatomy at the expense of large anatomical deformation. The ability to correct for this deformation is critical to integrate the MR images into the CT-based treatment planning for radiotherapy. The ability to quantify and understand the physiological motion due to large changes in rectal filling can also improve the precision of image-guided procedures. The purpose of this study was to understand the biomechanical relationship between the prostate, rectum, and bladder using a finite element-based multi-organ deformable image registration method, 'Morfeus' developed at our institution. Patients diagnosed with prostate cancer were enrolled in the study. Gold seed markers were implanted in the prostate and MR scans performed with the ERC in place and its surrounding balloon inflated to varying volumes (0-100cc). The prostate, bladder, and rectum were then delineated, converted into finite element models, and assigned appropriate material properties. Morfeus was used to assign surface interfaces between the adjacent organs and deform the bladder and rectum from one position to another, obtaining the position of the prostate through finite element analysis. This approach achieves sub-voxel accuracy of image co-registration in the context of a large ERC deformation, while providing a biomechanical understanding of the multi-organ physiological relationship between the prostate, bladder, and rectum. The development of a deformable registration strategy is essential to integrate the superior information offered in MR images into the treatment planning process.

Differential Calculus on h-Deformed Spaces

NASA Astrophysics Data System (ADS)

Herlemont, Basile; Ogievetsky, Oleg

2017-10-01

We construct the rings of generalized differential operators on the h-deformed vector space of gl-type. In contrast to the q-deformed vector space, where the ring of differential operators is unique up to an isomorphism, the general ring of h-deformed differential operators {Diff}_{h},σ(n) is labeled by a rational function σ in n variables, satisfying an over-determined system of finite-difference equations. We obtain the general solution of the system and describe some properties of the rings {Diff}_{h},σ(n).

Craniofacial neurofibromatosis: treatment of the midface deformity.

PubMed

Singhal, Dhruv; Chen, Yi-Chieh; Tsai, Yueh-Ju; Yu, Chung-Chih; Chen, Hung Chang; Chen, Yu-Ray; Chen, Philip Kuo-Ting

2014-07-01

Craniofacial Neurofibromatosis is a benign but devastating disease. While the most common location of facial involvement is the orbito-temporal region, patients often present with significant mid-face deformities. We reviewed our experience with Craniofacial Neurofibromatosis from June 1981 to June 2011 and included patients with midface soft tissue deformities defined as gross alteration of nasal or upper lip symmetry. Data reviewed included the medical records and photobank. Over 30 years, 52 patients presented to and underwent surgical management for Craniofacial Neurofibromatosis at the Chang Gung Craniofacial Center. 23 patients (43%) demonstrated gross mid-facial deformities at initial evaluation. 55% of patients with lip deformities and 28% of patients with nasal deformities demonstrated no direct tumour involvement. The respective deformity was solely due to secondary gravitational effects from neurofibromas of the cheek subunit. Primary tumour infiltration of the nasal and/or labial subunits was treated with excision followed by various methods of reconstruction including lower lateral cartilage repositioning, forehead flaps, free flaps, and/or oral commissure suspension. Soft tissue deformities of the midface are very common in patients with Craniofacial Neurofibromatosis and profoundly affect overall aesthetic outcomes. Distinguishing primary from secondary involvement of the midface assists in surgical decision making. Copyright © 2013 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.

Ultrasound evaluation of foot deformities in infants.

PubMed

Miron, Marie-Claude; Grimard, Guy

2016-02-01

Foot deformity in infants is the most common congenital musculoskeletal condition. A precise diagnosis can sometimes be impossible to establish clinically. Radiologic imaging plays a major role in the evaluation of musculoskeletal abnormalities. However conventional imaging techniques, such as plain radiographs of the foot, are of very little help in this age group because of the lack of ossification of the tarsal bones. US presents a significant advantage because it permits the visualization of cartilaginous structures. This leads to the detailed assessment of foot deformities in infants. Furthermore, US can also be used as a dynamic imaging modality. Different scanning views are beneficial to evaluate the complete anatomy of the foot; depending on the suspected clinical diagnosis, some planes are more informative to display the pathological features of a specific deformity. We describe the US findings of five of the most common foot deformities referred to our pediatric orthopedic clinic (clubfoot, simple metatarsus adductus, skewfoot, and oblique and vertical talus). For each deformity we propose a specific imaging protocol based on US to provide an accurate diagnosis. US is a complementary tool to the clinical examination for determining the diagnosis and the severity of the deformity and also for monitoring the efficacy of treatment. Radiologists investigating foot deformities in infants should consider using US for the detailed assessment of the foot in this age group.

Cirque du Monde as a health intervention: perceptions of medical students and social circus experts.

PubMed

Fournier, Cynthia; Drouin, Mélodie-Anne; Marcoux, Jérémie; Garel, Patricia; Bochud, Emmanuel; Théberge, Julie; Aubertin, Patrice; Favreau, Gil; Fleet, Richard

2014-11-01

To present Cirque du Soleil's social circus program, Cirque du Monde, to explore its potential as a primary health care tool for family physicians. A review of the literature in PubMed, the Cochrane Library, PsycINFO, LaPresse, Eureka, Google Scholar, and Érudit using the key words circus, social circus, Cirque du Monde, and Cirque du Soleil; a Montreal-based initiative, Espace Transition, modeled on Cirque du Monde; and personal communication with Cirque du Soleil's Social Circus Training Advisor. The first 50 articles or websites identified for each key word in each of the databases were examined on the basis of their titles and abstracts in the case of articles, and on the basis of their titles and page content in the case of websites. Articles and websites that explored an aspect of social circuses or that described an intervention that involved circuses were then retained for analysis. Because all literature on social circuses was searched, no criterion for year of publication was used. No articles on the social circus as a health intervention were found. One study on the use of the circus as an intervention in schools was identified. It demonstrated an increase in self-esteem in the children who took part. One study on the use of the circus in a First Nations community was found; it contained nonspecific, qualitative findings. The other articles identified were merely descriptions of social circuses. One website was identified on the use of the social circus to help youth who had been treated in a hospital setting for major psychiatric disorders to re-enter the community. The team in the pediatric psychiatry department at Centre Hospitalier Universitaire Sainte-Justine, the children's hospital in Montreal, Que, was contacted; they were leading this project, called Espace Transition. The unpublished preliminary findings of its pilot project demonstrate substantial improvements in overall patient functioning. According to Cirque du Soleil, there are several

A Variational Principle for Reconstruction of Elastic Deformations in Shear Deformable Plates and Shells

NASA Technical Reports Server (NTRS)

Tessler, Alexander; Spangler, Jan L.

2003-01-01

A variational principle is formulated for the inverse problem of full-field reconstruction of three-dimensional plate/shell deformations from experimentally measured surface strains. The formulation is based upon the minimization of a least squares functional that uses the complete set of strain measures consistent with linear, first-order shear-deformation theory. The formulation, which accommodates for transverse shear deformation, is applicable for the analysis of thin and moderately thick plate and shell structures. The main benefit of the variational principle is that it is well suited for C(sup 0)-continuous displacement finite element discretizations, thus enabling the development of robust algorithms for application to complex civil and aeronautical structures. The methodology is especially aimed at the next generation of aerospace vehicles for use in real-time structural health monitoring systems.

Deformable image registration for tissues with large displacements

PubMed Central

Huang, Xishi; Ren, Jing; Green, Mark

2017-01-01

Abstract. Image registration for internal organs and soft tissues is considered extremely challenging due to organ shifts and tissue deformation caused by patients’ movements such as respiration and repositioning. In our previous work, we proposed a fast registration method for deformable tissues with small rotations. We extend our method to deformable registration of soft tissues with large displacements. We analyzed the deformation field of the liver by decomposing the deformation into shift, rotation, and pure deformation components and concluded that in many clinical cases, the liver deformation contains large rotations and small deformations. This analysis justified the use of linear elastic theory in our image registration method. We also proposed a region-based neuro-fuzzy transformation model to seamlessly stitch together local affine and local rigid models in different regions. We have performed the experiments on a liver MRI image set and showed the effectiveness of the proposed registration method. We have also compared the performance of the proposed method with the previous method on tissues with large rotations and showed that the proposed method outperformed the previous method when dealing with the combination of pure deformation and large rotations. Validation results show that we can achieve a target registration error of 1.87±0.87  mm and an average centerline distance error of 1.28±0.78  mm. The proposed technique has the potential to significantly improve registration capabilities and the quality of intraoperative image guidance. To the best of our knowledge, this is the first time that the complex displacement of the liver is explicitly separated into local pure deformation and rigid motion. PMID:28149924

Deformable micro torque swimmer

NASA Astrophysics Data System (ADS)

Ishikawa, Takuji; Tanaka, Tomoyuki; Omori, Toshihiro; Imai, Yohsuke

2015-11-01

We investigated the deformation of a ciliate swimming freely in a fluid otherwise at rest. The cell body was modeled as a capsule with a hyper elastic membrane enclosing Newtonian fluid. Thrust forces due to the ciliary beat were modeled as torques distributed above the cell body. Effects of the membrane elasticity, the aspect ratio of cell's reference shape and the density difference between the cell and the surrounding fluid were investigated. The results showed that the cell deformed like heart shape when Capillary number (Ca) was sufficiently large, and the swimming velocity decreased as Ca was increased. The gravity effect on the membrane tension suggested that the upwards and downwards swimming velocities of Paramecium might be reglated by the calcium ion channels distributed locally around the anterior end. Moreover, the gravity induced deformation made a cell directed vertically downwards, which resulted in a positive geotaxis like behavior with physical origin. These results are important to understand physiology of ciliate's biological responses to mechanical stimuli.

Paleoneurosurgical aspects of Proto-Bulgarian artificial skull deformations.

PubMed

Enchev, Yavor; Nedelkov, Grigoriy; Atanassova-Timeva, Nadezhda; Jordanov, Jordan

2010-12-01

Paleoneurosurgery represents a comparatively new developing direction of neurosurgery dealing with archaeological skull and spine finds and studying their neurosurgical aspects. Artificial skull deformation, as a bone artifact, naturally has been one of the main paleoneurosurgical research topics. Traditionally, the relevant neurosurgical literature has analyzed in detail the intentional skull deformations in South America's tribes. However, little is known about the artificial skull deformations of the Proto-Bulgarians, and what information exists is mostly due to anthropological studies. The Proto-Bulgarians originated from Central Asia, and distributed their skull deformation ritual on the Balkan Peninsula by their migration and domination. Proto-Bulgarian artificial skull deformation was an erect or oblique form of the anular type, and was achieved by 1 or 2 pressure bandages that were tightened around a newborn's head for a sufficiently long period. The intentional skull deformation in Proto-Bulgarians was not associated with neurological deficits and/or mental retardation. No indirect signs of chronic elevated intracranial pressure were found on the 3D CT reconstruction of the artificially deformed skulls.

Deformation field heterogeneity in punch indentation

PubMed Central

Murthy, Tejas G.; Saldana, Christopher; Hudspeth, Matthew; M'Saoubi, Rachid

2014-01-01

Plastic heterogeneity in indentation is fundamental for understanding mechanics of hardness testing and impression-based deformation processing methods. The heterogeneous deformation underlying plane-strain indentation was investigated in plastic loading of copper by a flat punch. Deformation parameters were measured, in situ, by tracking the motion of asperities in high-speed optical imaging. These measurements were coupled with multi-scale analyses of strength, microstructure and crystallographic texture in the vicinity of the indentation. Self-consistency is demonstrated in description of the deformation field using the in situ mechanics-based measurements and post-mortem materials characterization. Salient features of the punch indentation process elucidated include, among others, the presence of a dead-metal zone underneath the indenter, regions of intense strain rate (e.g. slip lines) and extent of the plastic flow field. Perhaps more intriguing are the transitions between shear-type and compression-type deformation modes over the indentation region that were quantified by the high-resolution crystallographic texture measurements. The evolution of the field concomitant to the progress of indentation is discussed and primary differences between the mechanics of indentation for a rigid perfectly plastic material and a strain-hardening material are described. PMID:24910521

Orbital shape in intentional skull deformations and adult sagittal craniosynostoses.

PubMed

Sandy, Ronak; Hennocq, Quentin; Nysjö, Johan; Giran, Guillaume; Friess, Martin; Khonsari, Roman Hossein

2018-06-21

Intentional cranial deformations are the result of external mechanical forces exerted on the skull vault that modify the morphology of various craniofacial structures such as the skull base, the orbits and the zygoma. In this controlled study, we investigated the 3D shape of the orbital inner mould and the orbital volume in various types of intentional deformations and in adult non-operated scaphocephaly - the most common type of craniosynostosis - using dedicated morphometric methods. CT scans were performed on 32 adult skulls with intentional deformations, 21 adult skull with scaphocephaly and 17 non-deformed adult skulls from the collections of the Muséum national d'Histoire naturelle in Paris, France. The intentional deformations group included six skulls with Toulouse deformations, eight skulls with circumferential deformations and 18 skulls with antero-posterior deformations. Mean shape models were generated based on a semi-automatic segmentation technique. Orbits were then aligned and compared qualitatively and quantitatively using colour-coded distance maps and by computing the mean absolute distance, the Hausdorff distance, and the Dice similarity coefficient. Orbital symmetry was assessed after mirroring, superimposition and Dice similarity coefficient computation. We showed that orbital shapes were significantly and symmetrically modified in intentional deformations and scaphocephaly compared with non-deformed control skulls. Antero-posterior and circumferential deformations demonstrated a similar and severe orbital deformation pattern resulting in significant smaller orbital volumes. Scaphocephaly and Toulouse deformations had similar deformation patterns but had no effect on orbital volumes. This study showed that intentional deformations and scaphocephaly significantly interact with orbital growth. Our approach was nevertheless not sufficient to identify specific modifications caused by the different types of skull deformations or by scaphocephaly. �

Geodetic deformation monitoring at Pendidikan Diponegoro Dam

NASA Astrophysics Data System (ADS)

Yuwono, Bambang Darmo; Awaluddin, Moehammad; Yusuf, M. A.; Fadillah, Rizki

2017-07-01

Deformation monitoring is one indicator to assess the feasibility of Dam. In order to get the correct result of the deformation, it is necessary to determine appropriate deformation monitoring network and the observation data should be analyse and evaluated carefully. Measurement and analysis of deformation requires relatively accurate data and the precision is high enough, one of the observation method that used is GPS (Global Positioning System). The research was conducted at Pendidikan Undip Dams is Dam which is located in Tembang. Diponegoro Dam was built in 2013 and a volume of 50.86 m3 of water, inundation normal width of up to 13,500 m2. The main purpose of these building is not only for drainage but also for education and micro hydro power plant etc. The main goal of this reasearch was to monitor and analyze the deformation at Pendidikan Undip Dam and to determaine whether GPS measurement could meet accuracy requirement for dam deformation measurements. Measurements were made 2 times over 2 years, 2015 and 2016 using dual frequency GPS receivers with static methods and processed by Scientific Software GAMIT 10.6

Compliant deformable mirror approach for wavefront improvement

NASA Astrophysics Data System (ADS)

Clark, James H.; Penado, F. Ernesto

2016-04-01

We describe a compliant static deformable mirror approach to reduce the wavefront concavity at the Navy Precision Optical Interferometer (NPOI). A single actuator pressing on the back surface of just one of the relay mirrors deforms the front surface in a correcting convex shape. Our design uses the mechanical advantage gained from a force actuator sandwiched between a rear flexure plate and the back surface of the mirror. We superimpose wavefront contour measurements with our finite element deformed mirror model. An example analysis showed improvement from 210-nm concave-concave wavefront to 51-nm concave-concave wavefront. With our present model, a 100-nm actuator increment displaces the mirror surface by 1.1 nm. We describe the need for wavefront improvement that arises from the NPOI reconfigurable array, offer a practical design approach, and analyze the support structure and compliant deformable mirror using the finite element method. We conclude that a 20.3-cm-diameter, 1.9-cm-thick Zerodur® mirror shows that it is possible to deform the reflective surface and cancel out three-fourths of the wavefront deformation without overstressing the material.

Research on wire rope deformation distribution of WR-CVT

NASA Astrophysics Data System (ADS)

Zhang, Wu; Guo, Wei; Zhang, Chuanwei; Lu, Zhengxiong; Xu, Xiaobin

2017-07-01

A wire rope continuously variable transmissions (WR-CVT) has been introduced in the paper, in view of its less research, this paper mainly studied the deformation distribution of 6×7+IWS bending wire rope. The results shown that in the same section, half of the side strands are in a stretched state and half are in a compressed state. When the transmission ratio i=2.35, the maximum deformation and the minimum deformation are decrease when section U1 to U2, U3 transition. Wire deformation distribution when the transmission ratio i=0.42 is similar to that of i=0.2.35. Wire deformation amount and the deformation difference decrease as the transmission ratio decreases, this shows that the increase in the bending radius of the wire will make the wire deformation more uniform, and the reduction of the deformation difference will also reduce the wear. This study provides a basis for the study of fatigue and wears failure of WR-CVT components.

An electromechanical based deformable model for soft tissue simulation.

PubMed

Zhong, Yongmin; Shirinzadeh, Bijan; Smith, Julian; Gu, Chengfan

2009-11-01

Soft tissue deformation is of great importance to surgery simulation. Although a significant amount of research efforts have been dedicated to simulating the behaviours of soft tissues, modelling of soft tissue deformation is still a challenging problem. This paper presents a new deformable model for simulation of soft tissue deformation from the electromechanical viewpoint of soft tissues. Soft tissue deformation is formulated as a reaction-diffusion process coupled with a mechanical load. The mechanical load applied to a soft tissue to cause a deformation is incorporated into the reaction-diffusion system, and consequently distributed among mass points of the soft tissue. Reaction-diffusion of mechanical load and non-rigid mechanics of motion are combined to govern the simulation dynamics of soft tissue deformation. An improved reaction-diffusion model is developed to describe the distribution of the mechanical load in soft tissues. A three-layer artificial cellular neural network is constructed to solve the reaction-diffusion model for real-time simulation of soft tissue deformation. A gradient based method is established to derive internal forces from the distribution of the mechanical load. Integration with a haptic device has also been achieved to simulate soft tissue deformation with haptic feedback. The proposed methodology does not only predict the typical behaviours of living tissues, but it also accepts both local and large-range deformations. It also accommodates isotropic, anisotropic and inhomogeneous deformations by simple modification of diffusion coefficients.

Restauration fonctionnelle du rachis : effet du niveau initial de douleur sur les performances des sujets lombalgiques chroniques

PubMed Central

Caby, Isabelle; Olivier, N; Mendelek, F; Kheir, R Bou; Vanvelcenaher, J; Pelayo, P

2014-01-01

HISTORIQUE : La lombalgie chronique est une douleur lombaire persistante d’origine multifactorielle. Le niveau de douleur initial reste faiblement utilisé pour analyser et comparer les réponses des patients lombalgiques au programme de reconditionnement. OBJECTIFS : Apprécier et évaluer les réponses des sujets lombalgiques chroniques très douloureux à une prise en charge dynamique et intensive. MÉTHODOLOGIE : 144 sujets atteints de lombalgie chronique ont été inclus dans un programme de restauration fonctionnelle du rachis de 5 semaines. Les sujets ont été classés en deux groupes de niveau de douleur: un groupe atteint de douleur sévère (n = 28) et un groupe atteint de douleur légère à modérée (n = 106). L’ensemble des sujets ont bénéficié d’une prise en charge identique comprenant principalement de la kinésithérapie, de l’ergothérapie, du reconditionnement musculaire et cardio-vasculaire ainsi qu’un suivi psychologique. Les paramètres physiques (flexibilité, force musculaire) et psychologiques (qualité de vie) ont été mesurés avant (T0) et après le programme (T5sem). RÉSULTATS : L’ensemble des performances physiques et fonctionnelles des sujets très douloureux sont moins bonnes et le retentissement de la lombalgie sur la qualité de vie, pour ces mêmes sujets, est majoré à T0. Toutes les différences significatives constatées à T0 entre les deux groupes s’effacent à T5sem. CONCLUSIONS : Les sujets lombalgiques chroniques très douloureux répondent favorablement au programme dynamique et intensif. L’intensité douloureuse de la lombalgie n’aurait pas d’effet sur les réponses au programme. La restauration fonctionnelle du rachis apporterait aux sujets la possibilité de mieux gérer leur douleur quel que soit son niveau. PMID:25299476

Etude des facteurs de risque du retard de croissance intra-utérin à Lubumbashi

PubMed Central

Moyambe, Jules Ngwe Thaba; Bernard, Pierre; Khang'Mate, Faustin; Nkoy, Albert Mwembo Tambwe A; Mukalenge, Faustin Chenge; Makanda, Daudet; Twite, Eugene; Ndudula, Arthur Munkana; Lubamba, Cham; Kadingi, Arnauld Kabulu; Kayomb, Mutach; Kayamba, Prosper Kalenga Muenze

2013-01-01

Introduction Dans notre milieu, il n'existe aucune politique de prévention du Retard de Croissance Intra-Utérin (RCIU) clairement défini. L'objectif de ce travail était d'identifier les facteurs de risque de RCIU afin de proposer une stratégie de lutte contre cette pathologie en agissant surtout sur des facteurs pouvant faire l'objet d'une action préventive. Méthodes Une étude cas-témoins a été menée dans 11 centres hospitaliers de Lubumbashi en République Démocratique du Congo, de Janvier 2010 à Juin 2011, dans le but d'identifier les facteurs de risque du retard de croissance intra-utérin (RCIU). Au total 420 gestantes (cas et témoins) avec grossesse monofoetale d'au moins 24 semaines d'aménorrhée ont été inclues dans l'étude. Les cas correspondaient aux gestantes dont le poids du fœtus était resté inférieur au 10 eme percentile des courbes de référence d'Alexander, après 2 échographies successives réalisées à intervalle de 4 semaines. Les témoins correspondaient aux gestantes dont le poids du fœtus était supérieur ou égal au 10 eme percentile de mêmes courbes. A chaque cas a été apparié un témoin de même parité porteur d'une grossesse de même âge. Résultats L'analyse univariée a identifié comme facteurs de risque: la taille maternelle. Conclusion L'amélioration du niveau socio-économique des populations, la lutte contre le paludisme et les consultations prénatales mieux organisées couplées à une meilleure éducation sanitaire et nutritionnelle peuvent contribuer sensiblement à la réduction de la fréquence du RCIU à Lubumbashi. PMID:23504392

Finite Deformation of Magnetoelastic Film

DOE Office of Scientific and Technical Information (OSTI.GOV)

Barham, Matthew Ian

2011-05-31

A nonlinear two-dimensional theory is developed for thin magnetoelastic lms capable of large deformations. This is derived directly from three-dimensional theory. Signi cant simpli cations emerge in the descent from three dimensions to two, permitting the self eld generated by the body to be computed a posteriori. The model is specialized to isotropic elastomers with two material models. First weak magnetization is investigated leading to a free energy where magnetization and deformation are un-coupled. The second closely couples the magnetization and deformation. Numerical solutions are obtained to equilibrium boundary-value problems in which the membrane is subjected to lateral pressure andmore » an applied magnetic eld. An instability is inferred and investigated for the weak magnetization material model.« less

A Bed-Deformation Experiment Beneath Engabreen, Norway

NASA Astrophysics Data System (ADS)

Iverson, N. R.; Hooyer, T. S.; Fischer, U. H.; Cohen, D.; Jackson, M.; Moore, P. L.; Lappegard, G.; Kohler, J.

2001-12-01

Although deformation of sediment beneath ice masses may contribute to their motion and may sometimes enable fast glacier flow, both the kinematics and mechanics of deformation are controversial. This controversy stems, in part, from subglacial measurements that are difficult to interpret. Measurements have been made either beneath ice margins or remotely through boreholes with interpretive limitations caused by uncertain instrument position and performance, uncertain sediment thickness and bed geometry, and unknown disturbance of the bed and stress state by drilling. We have used a different approach made possible by the Svartisen Subglacial Laboratory, which enables human access to the bed of Engabreen, Norway, beneath 230 m of temperate ice. A trough (2 m x 1.5 m x 0.4 m deep) was blasted in the rock bed and filled with sediment (75 percent sand and gravel, 20 percent silt, 5 percent clay). Instruments were placed in the sediment to record shear deformation (tiltmeters), dilation and contraction, total normal stress, and pore-water pressure. Pore pressure was manipulated by feeding water to the base of the sediment with a high-pressure pump, operated in a rock tunnel 4 m below the bed surface. After irregular deformation during closure of ice on the sediment, shear deformation and volume change stopped, and total normal stress became constant at 2.2 MPa. Subsequent pump tests, which lasted several hours, induced pore-water pressures greater than 70 percent of the total normal stress and resulted in shear deformation over most of the sediment thickness with attendant dilation. Ice separated from the sediment when effective normal stress was lowest, arresting shear deformation. Displacement profiles during pump tests were similar to those observed by Boulton and co-workers at Breidamerkurjökull, Iceland, with rates of shear strain increasing upward toward the glacier sole. Such deformation does not require viscous deformation resistance and is expected in a

Deformation Monitoring and Analysis of Lsp Landslide Based on Gbinsar

NASA Astrophysics Data System (ADS)

Zhou, L.; Guo, J.; Yang, F.

2018-05-01

Monitoring and analyzing the deformation of the river landslide in city to master the deformation law of landslide, which is an important means of landslide safety assessment. In this paper, aiming at the stability of the Liu Sha Peninsula Landslide during its strengthening process after the landslide disaster. Continuous and high precision deformation monitoring of the landslide was carried out by GBInSAR technique. Meanwhile, the two-dimensional deformation time series pictures of the landslide body were retrieved by the time series analysis method. The deformation monitoring and analysis results show that the reinforcement belt on the landslide body was basically stable and the deformation of most PS points on the reinforcement belt was within 1 mm. The deformation of most areas on the landslide body was basically within 4 mm, and the deformation presented obvious nonlinear changes. GBInSAR technique can quickly and effectively obtain the entire deformation information of the river landslide and the evolution process of deformation.

Monotonous and stepwise character of deformation accumulation as a hierarchically organized process under high-temperature deformation of aluminum-magnesium alloy

NASA Astrophysics Data System (ADS)

Makarov, S. V.; Plotnikov, V. A.; Lysikov, M. V.

2017-12-01

Stepwise kinetics of deformation accumulation and monotonous and pulsed acoustic emission bear witness to the active role of acoustic emission in deformation processes. A standing acoustic wave in the region of deformation localization determines the effect of self-organization of dislocations on macroscopic scales around the natural resonator of the system.

Deformation associated with continental normal faults

NASA Astrophysics Data System (ADS)

Resor, Phillip G.

Deformation associated with normal fault earthquakes and geologic structures provide insights into the seismic cycle as it unfolds over time scales from seconds to millions of years. Improved understanding of normal faulting will lead to more accurate seismic hazard assessments and prediction of associated structures. High-precision aftershock locations for the 1995 Kozani-Grevena earthquake (Mw 6.5), Greece image a segmented master fault and antithetic faults. This three-dimensional fault geometry is typical of normal fault systems mapped from outcrop or interpreted from reflection seismic data and illustrates the importance of incorporating three-dimensional fault geometry in mechanical models. Subsurface fault slip associated with the Kozani-Grevena and 1999 Hector Mine (Mw 7.1) earthquakes is modeled using a new method for slip inversion on three-dimensional fault surfaces. Incorporation of three-dimensional fault geometry improves the fit to the geodetic data while honoring aftershock distributions and surface ruptures. GPS Surveying of deformed bedding surfaces associated with normal faulting in the western Grand Canyon reveals patterns of deformation that are similar to those observed by interferometric satellite radar interferometry (InSAR) for the Kozani Grevena earthquake with a prominent down-warp in the hanging wall and a lesser up-warp in the footwall. However, deformation associated with the Kozani-Grevena earthquake extends ˜20 km from the fault surface trace, while the folds in the western Grand Canyon only extend 500 m into the footwall and 1500 m into the hanging wall. A comparison of mechanical and kinematic models illustrates advantages of mechanical models in exploring normal faulting processes including incorporation of both deformation and causative forces, and the opportunity to incorporate more complex fault geometry and constitutive properties. Elastic models with antithetic or synthetic faults or joints in association with a master

Microfluidic assay of the deformability of primitive erythroblasts.

PubMed

Zhou, Sitong; Huang, Yu-Shan; Kingsley, Paul D; Cyr, Kathryn H; Palis, James; Wan, Jiandi

2017-09-01

Primitive erythroblasts (precursors of red blood cells) enter vascular circulation during the embryonic period and mature while circulating. As a result, primitive erythroblasts constantly experience significant hemodynamic shear stress. Shear-induced deformation of primitive erythroblasts however, is poorly studied. In this work, we examined the deformability of primitive erythroblasts at physiologically relevant flow conditions in microfluidic channels and identified the regulatory roles of the maturation stage of primitive erythroblasts and cytoskeletal protein 4.1 R in shear-induced cell deformation. The results showed that the maturation stage affected the deformability of primitive erythroblasts significantly and that primitive erythroblasts at later maturational stages exhibited a better deformability due to a matured cytoskeletal structure in the cell membrane.

Structural Transformations in Metallic Materials During Plastic Deformation

NASA Astrophysics Data System (ADS)

Zasimchuk, E.; Turchak, T.; Baskova, A.; Chausov, N.; Hutsaylyuk, V.

2017-03-01

In this paper, the structure formation during the plastic deformation of polycrystalline nickel and aluminum based alloy 2024-T3 is investigated. The possibility of the relaxation and synergetic structure formation is examined. It is shown the deformation softening to be due to the crystallization of the amorphous structure of hydrodynamics flow channels (synergetic structure) HC as micrograins and their subsequent growth. The possible mechanism of micrograins' growth is proposed. The deformation processes change the phase composition of the multiphase alloy 2024-T3. It is shown by the quantitative analysis of the structures which were deformed in different regimes of the alloy samples. A method for increasing of the fatigue life through a dynamic pre-deformation is suggested.

Dielectric elastomer membranes undergoing inhomogeneous deformation

NASA Astrophysics Data System (ADS)

He, Tianhu; Zhao, Xuanhe; Suo, Zhigang

2009-10-01

Dielectric elastomers are capable of large deformation subject to an electric voltage and are promising for use as actuators, sensors, and generators. Because of large deformation, nonlinear equations of states, and diverse modes of failure, modeling the process of electromechanical transduction has been challenging. This paper studies a membrane of a dielectric elastomer deformed into an out-of-plane axisymmetric shape, a configuration used in a family of commercial devices known as the universal muscle actuators. The kinematics of deformation and charging, together with thermodynamics, leads to equations that govern the state of equilibrium. Numerical results indicate that the field in the membrane can be very inhomogeneous, and that the membrane is susceptible to several modes of failure, including electrical breakdown, loss of tension, and rupture by stretch. Care is needed in the design to balance the requirements of averting various modes of failure while using the material efficiently.

Deformable and conformal silk hydrogel inverse opal

PubMed Central

Kim, Sookyoung; Kim, Sunghwan

2017-01-01

Photonic crystals (PhCs) efficiently manipulate photons at the nanoscale. Applying these crystals to biological tissue that has been subjected to large deformation and humid environments can lead to fascinating bioapplications such as in vivo biosensors and artificial ocular prostheses. These applications require that these PhCs have mechanical durability, deformability, and biocompatibility. Herein, we introduce a deformable and conformal silk hydrogel inverse opal (SHIO); the photonic lattice of this 3D PhC can be deformed by mechanical strain. This SHIO is prepared by the UV cross-linking of a liquid stilbene/silk solution, to give a transparent and elastic hydrogel. The pseudophotonic band gap (pseudo-PBG) of this material can be stably tuned by deformation of the photonic lattice (stretching, bending, and compressing). Proof-of-concept experiments demonstrate that the SHIO can be applied as an ocular prosthesis for better vision, such as that provided by the tapeta lucida of nocturnal or deep-sea animals. PMID:28559327

Infinitesimal Deformations of a Formal Symplectic Groupoid

NASA Astrophysics Data System (ADS)

Karabegov, Alexander

2011-09-01

Given a formal symplectic groupoid G over a Poisson manifold ( M, π 0), we define a new object, an infinitesimal deformation of G, which can be thought of as a formal symplectic groupoid over the manifold M equipped with an infinitesimal deformation {π_0 + \\varepsilon π_1} of the Poisson bivector field π 0. To any pair of natural star products {(ast,tildeast)} having the same formal symplectic groupoid G we relate an infinitesimal deformation of G. We call it the deformation groupoid of the pair {(ast,tildeast)} . To each star product with separation of variables {ast} on a Kähler-Poisson manifold M we relate another star product with separation of variables {hatast} on M. We build an algorithm for calculating the principal symbols of the components of the logarithm of the formal Berezin transform of a star product with separation of variables {ast} . This algorithm is based upon the deformation groupoid of the pair {(ast,hatast)}.

Heavy Deformation of Patented Near-Eutectoid Steel

NASA Astrophysics Data System (ADS)

Khanchandani, Heena; Banerjee, M. K.

2018-01-01

Evolution of microstructure in the patented near-eutectoid steel, forged under varying situations, is critically examined in the present investigation. Steel with 0.74 wt.% carbon is isothermally annealed at 500 °C to obtain fine pearlite microstructure. Steel samples, so patented, are subjected to mechanical deformation by forging at various temperatures with different amount of thickness reduction. Microstructural analyses have revealed that mechanical deformation by forging at lower temperatures brings about partial dissolution of cementite, which is followed by the formation of ɛ-carbide in the microstructures. In contrast, cementite is precipitated within ferrite matrix upon warm or hot forging at higher temperatures. It is further observed that increasing deformation percent during low-temperature forging reduces interlamellar spacing of pearlite, whereas an opposite trend is noticed in case of deformation at higher temperature; moreover, deformation induced the change in interlamellar spacing and formation of fine carbide phases in microstructures has caused appreciable enhancement in hardness of the steel.

Deformation of metal brackets: a comparative study.

PubMed

Flores, D A; Choi, L K; Caruso, J M; Tomlinson, J L; Scott, G E; Jeiroudi, M T

1994-01-01

The purpose of this study was to determine the effect of material and design on the force and stress required to permanently deform metal brackets. Fourteen types of metal brackets were categorized according to raw material composition, slot torque degree, and wing type. Five types of raw materials, three types of slot torque degree, and four types of wing design were tested using an archwire torque test developed by Flores. An analysis of variance (ANOVA) and t-test showed that all three categories had a significant effect on the force and stress needed to permanently deform metal brackets. Of the three, raw material had the greatest effect on the amount of force. Results showed that 17-4PH and 303S had higher yield strengths and regular twin brackets had higher resistance to deformation. Also, as slot torque degree increased, brackets deformed with less force. Result confirmed that brackets requiring the greatest stress to permanently deform were made of steel with the greatest hardness.

Dynamic deformation analysis of light-weight mirror

NASA Astrophysics Data System (ADS)

Zhang, Yingtao; Cao, Xuedong; Kuang, Long; Yang, Wei

2012-10-01

In the process of optical dynamic target work, under the effort of the arm of dynamic target, the mirror needs to do circular motion, additional accelerated motion and uniform motion. The maximum acceleration is 10°/s2 and the maximum velocity is 30°/s. In this paper, we mostly analyze the dynamic deformation of a 600 mm honeycomb light-weight mirror of a certain dynamic target. Using the FEA (finite element analysis) method, first of all, we analyze the deformation of the light-weight mirror induced in gravity at different position; later, the dynamic deformation of light-weight mirror is analyzed in detailed. The analysis results indicate that, when the maximum acceleration is 10°/s2 and the maximum velocity is 30°/s, the centripetal force is 5% of the gravity at the equal mass, and the dynamic deformation of the mirror is 6.1% of the deformation induced by gravity.

Core Characteristics Deterioration due to Plastic Deformation

NASA Astrophysics Data System (ADS)

Kaido, Chikara; Arai, Satoshi

This paper discusses the effect of plastic deformation at core manufacturing on the characteristics of cores where non-oriented electrical steel sheets are used as core material. Exciting field and iron loss increase proportionally to plastic deformation in the case of rP<10, where rP is a ratio of plastic deformation to that at yield point. In this region, anomalous eddy currents increase because plastic deformations of crystalline grains are distributed and then the flux distribution is induced. In the case of rP>20, the deterioration tend to saturate, and the increases in magnetic field and iron loss are 1000 to 1500A/m and 2 to 4W/kg. They are related to grain size, and high grade with larger grain may have lager field increase and smaller iron loss increase. Anomalous eddy current losses scarcely increase in this region. In actual motors, the plastic deformation affects iron loss increase although exciting current increases a little.

Thin-skinned deformation of sedimentary rocks in Valles Marineris, Mars

USGS Publications Warehouse

Metz, Joannah; Grotzinger, John P.; Okubo, Chris; Milliken, Ralph

2010-01-01

Deformation of sedimentary rocks is widespread within Valles Marineris, characterized by both plastic and brittle deformation identified in Candor, Melas, and Ius Chasmata. We identified four deformation styles using HiRISE and CTX images: kilometer-scale convolute folds, detached slabs, folded strata, and pull-apart structures. Convolute folds are detached rounded slabs of material with alternating dark- and light-toned strata and a fold wavelength of about 1 km. The detached slabs are isolated rounded blocks of material, but they exhibit only highly localized evidence of stratification. Folded strata are composed of continuously folded layers that are not detached. Pull-apart structures are composed of stratified rock that has broken off into small irregularly shaped pieces showing evidence of brittle deformation. Some areas exhibit multiple styles of deformation and grade from one type of deformation into another. The deformed rocks are observed over thousands of kilometers, are limited to discrete stratigraphic intervals, and occur over a wide range in elevations. All deformation styles appear to be of likely thin-skinned origin. CRISM reflectance spectra show that some of the deformed sediments contain a component of monohydrated and polyhydrated sulfates. Several mechanisms could be responsible for the deformation of sedimentary rocks in Valles Marineris, such as subaerial or subaqueous gravitational slumping or sliding and soft sediment deformation, where the latter could include impact-induced or seismically induced liquefaction. These mechanisms are evaluated based on their expected pattern, scale, and areal extent of deformation. Deformation produced from slow subaerial or subaqueous landsliding and liquefaction is consistent with the deformation observed in Valles Marineris.

Assessment of orofacial characteristics and oral pathology associated with cri-du-chat syndrome.

PubMed

Rodríguez-Caballero, A; Torres-Lagares, D; Yáñez-Vico, R-M; Gutiérrez-Pérez, J-L; Machuca-Portillo, G

2012-03-01

To obtain a deeper insight into the difficulties individuals with cri-du-chat syndrome experience by means of the analysis of the most common features and oral pathology observed in the subjects enrolled in the study. Intra-oral and extra-oral features of a total of 33 patients with cri-du-chat syndrome (the larger sample so far analyzed) through their clinical and photographic examination. Models, orthopantomographies, and teleradiographies have been collected to establish a pattern as accurate as possible of the oral pathology associated with these patients. The present descriptive study shows that patients with cri-du-chat syndrome present with a series of orofacial features such as mandibular retrognathism, high palate, and variable malocclusion, more commonly anterior open-bite. Most patients also present with perioral muscle relaxation with labial incompetence and short philtrum. As regards oral pathology, these patients suffer dental erosions provoked by gastroesophageal reflux and attritions because of intense day-and-night bruxism. The odontologists' familiarity with the orofacial pathology associated with cri-du-chat syndrome and with the specific needs such disorder conveys should improve the quality of the buccodental treatment these professionals may offer to these patients. © 2011 John Wiley & Sons A/S.

Stent Design Affects Femoropopliteal Artery Deformation.

PubMed

MacTaggart, Jason; Poulson, William; Seas, Andreas; Deegan, Paul; Lomneth, Carol; Desyatova, Anastasia; Maleckis, Kaspars; Kamenskiy, Alexey

2018-03-23

Poor durability of femoropopliteal artery (FPA) stenting is multifactorial, and severe FPA deformations occurring with limb flexion are likely involved. Different stent designs result in dissimilar stent-artery interactions, but the degree of these effects in the FPA is insufficiently understood. To determine how different stent designs affect limb flexion-induced FPA deformations. Retrievable markers were deployed into n = 28 FPAs of lightly embalmed human cadavers. Bodies were perfused and CT images were acquired with limbs in the standing, walking, sitting, and gardening postures. Image analysis allowed measurement of baseline FPA foreshortening, bending, and twisting associated with each posture. Markers were retrieved and 7 different stents were deployed across the adductor hiatus in the same limbs. Markers were then redeployed in the stented FPAs, and limbs were reimaged. Baseline and stented FPA deformations were compared to determine the influence of each stent design. Proximal to the stent, Innova, Supera, and SmartFlex exacerbated foreshortening, SmartFlex exacerbated twisting, and SmartControl restricted bending of the FPA. Within the stent, all devices except Viabahn restricted foreshortening; Supera, SmartControl, and AbsolutePro restricted twisting; SmartFlex and Innova exacerbated twisting; and Supera and Viabahn restricted bending. Distal to the stents, all devices except AbsolutePro and Innova exacerbated foreshortening, and Viabahn, Supera, Zilver, and SmartControl exacerbated twisting. All stents except Supera were pinched in flexed limb postures. Peripheral self-expanding stents significantly affect limb flexion-induced FPA deformations, but in different ways. Although certain designs seem to accommodate some deformation modes, no device was able to match all FPA deformations.

Orthopaedic deformities associated with lumbosacral spinal lipomas.

PubMed

Gourineni, Prasad; Dias, Luciano; Blanco, Ronaldo; Muppavarapu, Satheesh

2009-12-01

Lipomeningocele is the most common cause of occult spinal dysraphism and spinal cord tethering. Children with this condition seem normal at birth except for cutaneous signs, and the initial complaints are usually musculoskeletal. We studied the orthopaedic deformities observed in this condition. We reviewed the medical charts of 159 patients with a diagnosis of lipoma of the lumbosacral spine that were examined in the Myelodysplasia Clinic over 25 years. Of these patients, 122 were treated by a single orthopaedic surgeon (L.D.) and were studied in detail. Of these 122 patients, 45 were over 15 years of age at the time of the final follow-up. Most patients had cutaneous stigmata. Foot deformities were the most common orthopaedic problems, followed by scoliosis. In patients over 15 years of age, the incidence of foot deformities was 44.2% (36 feet), with 20 feet requiring surgical treatment. The most common foot deformities were cavovarus, cavus, and equinocavovarus. In 70% of the surgical cases, good correction was achieved with only one procedure. Foot surgeries in patients under the age of 8 years were usually soft tissue procedures, and bony procedures were performed primarily in patients over the age of 11 years. Orthopaedic deformities are common at the initial presentation in patients with occult spinal dysraphism. A careful clinical examination with a high index of suspicion for spinal cord anomalies is indicated in all cases of spinal and lower extremity deformities. Foot deformities are very common and surgical treatment is usually successful. A thorough follow-up evaluation, including manual muscle strength testing, should be performed routinely to detect tethering of the cord in the early stages and to prevent worsening of the orthopaedic deformities. This was a retrospective case study. Level 4.

EPA may modify Du Pont waiver for methanol fuel blends

DOE Office of Scientific and Technical Information (OSTI.GOV)

Anderson, E.V.

1985-09-02

The Environmental Protection Agency (EPA) granted a Clean Air ACt waiver to DuPont's blendstock of methanol and other cosolvent alcohols for use in unleaded gasoline. The waiver included some stringent fuel volatility requirements to control evaporative emissions that have kept the waiver from becoming the marketing tool for fuel alcohols that everyone expected it to be. EPA seems willing to amend the waiver as long as evaporative emissions controls are kept, but there are some difficult procedural issues to resolve first. To date, only small amounts of alcohol blends have been sold under the DuPont waiver because the blendstock tendsmore » to increase the volatility of gasoline.« less

The deformation record of olivine in mylonitic peridotites from the Finero Complex, Ivrea Zone: Separate deformation cycles during exhumation

NASA Astrophysics Data System (ADS)

Matysiak, Agnes K.; Trepmann, Claudia A.

2015-12-01

Mylonitic peridotites from the Finero complex are investigated to detect characteristic olivine microfabrics that can resolve separate deformation cycles at different metamorphic conditions. The heterogeneous olivine microstructures are characterized by deformed porphyroclasts surrounded by varying amounts of recrystallized grains. A well-developed but only locally preserved foam structure is present in recrystallized grain aggregates. This indicates an early stage of dynamic recrystallization and subsequent recovery and recrystallization at quasi-static stress conditions, where the strain energy was reduced such that a reduction in surface energy controlled grain boundary migration. Ultramylonites record a renewed stage of localized deformation and recrystallization by a second generation of recrystallized grains that do not show a foam structure. This second generation of recrystallized grains as well as sutured grain and kink band boundaries of porphyroclasts indicate that these microstructures developed during a stage of localized deformation after development of the foam structure. The heterogeneity of the microfabrics is interpreted to represent several (at least two) cycles of localized deformation separated by a marked hiatus with quasi-static recrystallization and recovery and eventually grain growth. The second deformation cycle did not only result in reactivation of preexisting shear zones but instead also locally affected the host rock that was not deformed in the first stage. Such stress cycles can result from sudden increases in differential stress imposed by seismic events, i.e., high stress-loading rates, during exhumation of the Finero complex.

Local deformation for soft tissue simulation

PubMed Central

Omar, Nadzeri; Zhong, Yongmin; Smith, Julian; Gu, Chengfan

2016-01-01

ABSTRACT This paper presents a new methodology to localize the deformation range to improve the computational efficiency for soft tissue simulation. This methodology identifies the local deformation range from the stress distribution in soft tissues due to an external force. A stress estimation method is used based on elastic theory to estimate the stress in soft tissues according to a depth from the contact surface. The proposed methodology can be used with both mass-spring and finite element modeling approaches for soft tissue deformation. Experimental results show that the proposed methodology can improve the computational efficiency while maintaining the modeling realism. PMID:27286482

Red blood cell-deformability measurement: review of techniques.

PubMed

Musielak, M

2009-01-01

Cell-deformability characterization involves general measurement of highly complex relationships between cell biology and physical forces to which the cell is subjected. The review takes account of the modern technical solutions simulating the action of the force applied to the red blood cell in macro- and microcirculation. Diffraction ektacytometers and rheoscopes measure the mean deformability value for the total red blood cell population investigated and the deformation distribution index of individual cells, respectively. Deformation assays of a whole single cell are possible by means of optical tweezers. The single cell-measuring setups for micropipette aspiration and atomic force microscopy allow conducting a selective investigation of deformation parameters (e.g., cytoplasm viscosity, viscoelastic membrane properties). The distinction between instrument sensitivity to various RBC-rheological features as well as the influence of temperature on measurement are discussed. The reports quoted confront fascinating possibilities of the techniques with their medical applications since the RBC-deformability has the key position in the etiology of a wide range of conditions.

Cancer du sein au Cameroun, profil histo-épidémiologique: à propos de 3044 cas

PubMed Central

Engbang, Jean Paul Ndamba; Essome, Henri; Koh, Valère Mve; Simo, Godefroy; Essam, Jean Daniel Sime; Mouelle, Albert Sone; Essame, Jean Louis Oyono

2015-01-01

Décrire les caractéristiques épidémiologiques et histo-pathologiques des tumeurs malignes du sein au Cameroun. Il s'agissait d'une étude rétrospective descriptive portant sur les tumeurs malignes du sein, colligées, dans les registres des différents laboratoires d'Anatomie Pathologique publiques et privés repartis dans cinq régions (centre, littoral, Ouest, Nord-ouest, Sud-ouest), pendant une période de 10 ans (2004-2013). Les paramètres étudiés étaient la fréquence, l’âge, le sexe, la localisation, le type et le grade histologique, et les récepteurs hormonaux. Un total de 3044 cas de cancers du sein a été recensé, soit une fréquence annuelle de 304,4 cas en moyenne. Le sexe féminin était le plus représenté avec 2971 cas (97,60%) et les hommes avec 73 cas (2,40%), soit un sexe ratio (H/F) de 0,02. L’âge moyen des patients était de 46±15,87 ans, avec des extrêmes de 13 et 95 ans. Selon la localisation, le sein gauche était atteint dans 1244 cas (52%) et le sein droit dans 1115 cas (47%). Au plan histologique, on retrouvait essentiellement des carcinomes avec 96,50% des cas, des sarcomes 1,39%, des lymphomes 1,07% et la maladie de Paget du mamelon, 1,03%. Les tumeurs épithéliales étaient infiltrantes dans 2049 cas (84,46%), avec une prédominance du carcinome canalaire infiltrant (1870 cas) et non infiltrantes dans 377 cas (15,54%). Le grade histo-pronostic de SBR avait révélé une prédominance du grade II dans 66% des cas. Les cancers du sein restent une pathologie fréquente au Cameroun et atteignent principalement la population féminine en âge de procréer. Ils sont caractérisés par la prédominance du carcinome canalaire infiltrant. PMID:26523182

[Adolescent scoliosis : From deformity to treatment].

PubMed

Schulze, A; Schrading, S; Betsch, M; Quack, V; Tingart, M

2015-11-01

Scoliosis affects up to 6 % of the population. The resulting spine deformity, the increasing risk of back pain, cosmetic aspects, pulmonary disorders if the Cobb angle is > 80°, and the progress of the deformity to > 50° after the end of growth indicate non-operative or operative therapy. In daily clinical practice, the classifications of scoliosis allow the therapy to be adapted. Classifications consider deformity, topography of the scoliosis, and the age at diagnosis. This publication gives an overview of the relevant and most common classifications in the treatment of adolescent scoliosis. For evaluation, the deformity measurement on the coronary radiographic projection of the total spine (Cobb angle) is relevant to therapy. The classification of topography, form, and the sagittal profile of the deformity of the spine are useful for preoperative planning of the fusion level. Classifications that take into account the age at the time of the diagnosis of scoliosis differentiate among early onset scoliosis (younger than 10 years of age), adolescent scoliosis (up to the end of growth), and adult scoliosis. Early onset scoliosis is subdivided by age and etiology. Therapy is derived from the classification of clinical and radiological findings. Classifications that take into account clinical and radiological parameters are essential components of modern scoliosis therapy.

κ-deformed Dirac oscillator in an external magnetic field

NASA Astrophysics Data System (ADS)

Chargui, Y.; Dhahbi, A.; Cherif, B.

2018-04-01

We study the solutions of the (2 + 1)-dimensional κ-deformed Dirac oscillator in the presence of a constant transverse magnetic field. We demonstrate how the deformation parameter affects the energy eigenvalues of the system and the corresponding eigenfunctions. Our findings suggest that this system could be used to detect experimentally the effect of the deformation. We also show that the hidden supersymmetry of the non-deformed system reduces to a hidden pseudo-supersymmetry having the same algebraic structure as a result of the κ-deformation.

Deformations of vector-scalar models

NASA Astrophysics Data System (ADS)

Barnich, Glenn; Boulanger, Nicolas; Henneaux, Marc; Julia, Bernard; Lekeu, Victor; Ranjbar, Arash

2018-02-01

Abelian vector fields non-minimally coupled to uncharged scalar fields arise in many contexts. We investigate here through algebraic methods their consistent deformations ("gaugings"), i.e., the deformations that preserve the number (but not necessarily the form or the algebra) of the gauge symmetries. Infinitesimal consistent deformations are given by the BRST cohomology classes at ghost number zero. We parametrize explicitly these classes in terms of various types of global symmetries and corresponding Noether currents through the characteristic cohomology related to antifields and equations of motion. The analysis applies to all ghost numbers and not just ghost number zero. We also provide a systematic discussion of the linear and quadratic constraints on these parameters that follow from higher-order consistency. Our work is relevant to the gaugings of extended supergravities.

Deformation properties of lead isotopes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tolokonnikov, S. V.; Borzov, I. N.; Lutostansky, Yu. S.

2016-01-15

The deformation properties of a long lead isotopic chain up to the neutron drip line are analyzed on the basis of the energy density functional (EDF) in the FaNDF{sup 0} Fayans form. The question of whether the ground state of neutron-deficient lead isotopes can have a stable deformation is studied in detail. The prediction of this deformation is contained in the results obtained on the basis of the HFB-17 and HFB-27 Skyrme EDF versions and reported on Internet. The present analysis reveals that this is at odds with experimental data on charge radii and magnetic moments of odd lead isotopes.more » The Fayans EDF version predicts a spherical ground state for all light lead isotopes, but some of them (for example, {sup 180}Pb and {sup 184}Pb) prove to be very soft—that is, close to the point of a phase transition to a deformed state. Also, the results obtained in our present study are compared with the predictions of some other Skyrme EDF versions, including SKM*, SLy4, SLy6, and UNE1. By and large, their predictions are closer to the results arising upon the application of the Fayans functional. For example, the SLy4 functional predicts, in just the same way as the FaNDF{sup 0} functional, a spherical shape for all nuclei of this region. The remaining three Skyrme EDF versions lead to a deformation of some light lead isotopes, but their number is substantially smaller than that in the case of the HFB-17 and HFB-27 functionals. Moreover, the respective deformation energy is substantially lower, which gives grounds to hope for the restoration of a spherical shape upon going beyond the mean-field approximation, which we use here. Also, the deformation properties of neutron-rich lead isotopes are studied up to the neutron drip line. Here, the results obtained with the FaNDF{sup 0} functional are compared with the predictions of the HFB-17, HFB-27, SKM*, and SLy4 Skyrme EDF versions. All of the EDF versions considered here predict the existence of a region where

Flow characteristics around a deformable stenosis under pulsatile flow condition

NASA Astrophysics Data System (ADS)

Choi, Woorak; Park, Jun Hong; Byeon, Hyeokjun; Lee, Sang Joon

2018-01-01

A specific portion of a vulnerable stenosis is deformed periodically under a pulsatile blood flow condition. Detailed analysis of such deformable stenosis is important because stenotic deformation can increase the likelihood of rupture, which may lead to sudden cardiac death or stroke. Various diagnostic indices have been developed for a nondeformable stenosis by using flow characteristics and resultant pressure drop across the stenosis. However, the effects of the stenotic deformation on the flow characteristics remain poorly understood. In this study, the flows around a deformable stenosis model and two different rigid stenosis models were investigated under a pulsatile flow condition. Particle image velocimetry was employed to measure flow structures around the three stenosis models. The deformable stenosis model was deformed to achieve high geometrical slope and height when the flow rate was increased. The deformation of the stenotic shape enhanced jet deflection toward the opposite vessel wall of the stenosis. The jet deflection in the deformable model increased the rate of jet velocity and turbulent kinetic energy (TKE) production as compared with those in the rigid models. The effect of stenotic deformation on the pulsating waveform related with the pressure drop was analyzed using the TKE production rate. The deformable stenosis model exhibited a phase delay of the peak point in the waveform. These results revealed the potential use of pressure drop waveform as a diagnostic index for deformable stenosis.

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

NASA Astrophysics Data System (ADS)

Savard, Stephane

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

Canny edge-based deformable image registration

NASA Astrophysics Data System (ADS)

Kearney, Vasant; Huang, Yihui; Mao, Weihua; Yuan, Baohong; Tang, Liping

2017-02-01

This work focuses on developing a 2D Canny edge-based deformable image registration (Canny DIR) algorithm to register in vivo white light images taken at various time points. This method uses a sparse interpolation deformation algorithm to sparsely register regions of the image with strong edge information. A stability criterion is enforced which removes regions of edges that do not deform in a smooth uniform manner. Using a synthetic mouse surface ground truth model, the accuracy of the Canny DIR algorithm was evaluated under axial rotation in the presence of deformation. The accuracy was also tested using fluorescent dye injections, which were then used for gamma analysis to establish a second ground truth. The results indicate that the Canny DIR algorithm performs better than rigid registration, intensity corrected Demons, and distinctive features for all evaluation matrices and ground truth scenarios. In conclusion Canny DIR performs well in the presence of the unique lighting and shading variations associated with white-light-based image registration.

Three-dimensional deformation of orthodontic brackets

PubMed Central

Melenka, Garrett W; Nobes, David S; Major, Paul W

2013-01-01

Braces are used by orthodontists to correct the misalignment of teeth in the mouth. Archwire rotation is a particular procedure used to correct tooth inclination. Wire rotation can result in deformation to the orthodontic brackets, and an orthodontic torque simulator has been designed to examine this wire–bracket interaction. An optical technique has been employed to measure the deformation due to size and geometric constraints of the orthodontic brackets. Images of orthodontic brackets are collected using a stereo microscope and two charge-coupled device cameras, and deformation of orthodontic brackets is measured using a three-dimensional digital image correlation technique. The three-dimensional deformation of orthodontic brackets will be evaluated. The repeatability of the three-dimensional digital image correlation measurement method was evaluated by performing 30 archwire rotation tests using the same bracket and archwire. Finally, five Damon 3MX and five In-Ovation R self-ligating brackets will be compared using this technique to demonstrate the effect of archwire rotation on bracket design. PMID:23762201

Three-dimensional deformation of orthodontic brackets.

PubMed

Melenka, Garrett W; Nobes, David S; Major, Paul W; Carey, Jason P

2013-01-01

Braces are used by orthodontists to correct the misalignment of teeth in the mouth. Archwire rotation is a particular procedure used to correct tooth inclination. Wire rotation can result in deformation to the orthodontic brackets, and an orthodontic torque simulator has been designed to examine this wire-bracket interaction. An optical technique has been employed to measure the deformation due to size and geometric constraints of the orthodontic brackets. Images of orthodontic brackets are collected using a stereo microscope and two charge-coupled device cameras, and deformation of orthodontic brackets is measured using a three-dimensional digital image correlation technique. The three-dimensional deformation of orthodontic brackets will be evaluated. The repeatability of the three-dimensional digital image correlation measurement method was evaluated by performing 30 archwire rotation tests using the same bracket and archwire. Finally, five Damon 3MX and five In-Ovation R self-ligating brackets will be compared using this technique to demonstrate the effect of archwire rotation on bracket design.

A ferrofluidic deformable mirror for ophthalmology

NASA Astrophysics Data System (ADS)

Macpherson, J. B.; Thibault, S.; Borra, E. F.; Ritcey, A. M.; Carufel, N.; Asselin, D.; Jerominek, H.; Campbell, M. C. W.

2005-09-01

Optical aberrations reduce the imaging quality of the human eye. In addition to degrading vision, this limits our ability to illuminate small points of the retina for therapeutic, surgical or diagnostic purposes. When viewing the rear of the eye, aberrations cause structures in the fundus to appear blurred, limiting the resolution of ophthalmoscopes (diagnostic instruments used to image the eye). Adaptive optics, such as deformable mirrors may be used to compensate for aberrations, allowing the eye to work as a diffraction-limited optical element. Unfortunately, this type of correction has not been widely available for ophthalmic applications because of the expense and technical limitations of current deformable mirrors. We present preliminary design and characterisation of a deformable mirror suitable for ophthalmology. In this ferrofluidic mirror, wavefronts are reflected from a fluid whose surface shape is controlled by a magnetic field. Challenges in design are outlined, as are advantages over traditional deformable mirrors.

Gravitational Redshift of Deformed Neutron Stars

NASA Astrophysics Data System (ADS)

Romero, Alexis; Zubairi, Omair; Weber, Fridolin

2015-04-01

Non-rotating neutron stars are generally treated in theoretical studies as perfect spheres. Such a treatment, however, may not be correct if strong magnetic fields are present and/or the pressure of the matter in the cores of neutron stars is non-isotropic, leading to neutron stars which are deformed. In this work, we investigate the impact of deformation on the gravitational redshift of neutron stars in the framework of general relativity. Using a parameterized metric to model non-spherical mass distributions, we derive an expression for the gravitational redshift in terms of the mass, radius, and deformity of a neutron star. Numerical solutions for the redshifts of sequences of deformed neutron stars are presented and observational implications are pointed out. This research is funded by the NIH through the Maximizing Access to Research Careers (MARC), under Grant Number: 5T34GM008303-25 and through the National Science Foundation under grant PHY-1411708.

A homogeneous 2D deformation of geological interest: Rotation shear

NASA Astrophysics Data System (ADS)

Bastida, Fernando; Bobillo-Ares, Nilo C.; Aller, Jesús; Lisle, Richard J.

2018-07-01

We define a simple two-dimensional deformation called "rotation shear". It has one line of no finite longitudinal strain with invariant direction and another one that rotates with the deformation. An analysis of this deformation is carried out. Rotation shear superficially resembles simple shear but the analysis reveals that the two deformations have very different properties. In general, lines deformed by simple shear show a more complex deformation history and undergo greater longitudinal strain, i.e. are more extended, than lines deformed by rotation shear. Rotation shear is used to explain the development of geological structures such as kink bands, ideal similar folds, crenulation and crenulation cleavage and shear zones.

Simulation of Deformation, Momentum and Energy Coupling Particles Deformed by Intense Shocks

NASA Astrophysics Data System (ADS)

Lieberthal, B.; Stewart, D. S.; Bdzil, J. B.; Najjar, F. M.; Balachandar, S.; Ling, Y.

2011-11-01

Modern energetic materials have embedded solids and inerts in an explosive matrix. A detonation in condensed phase materials, generates intense shocks that deform particles as the incident shock diffracts around them. The post-shock flow generates a wake behind the particle that is influenced by the shape changes of the particle. The gasdynamic flow in the explosive products and its interaction with the deformation of the particle must be treated simultaneously. Direct numerical simulations are carried out that vary the particle-to-surrounding density and impedance ratios to consider heavier and lighter particle. The vorticity deposited on the interface due to shock interaction with the particle, the resulting particle deformation and the net momentum and energy transferred to the particle, on the acoustic and longer viscous time scale are considered. The LLNL multi-physics hydrodynamic code ALE3D is used to carry out the simulations. BL, DSS and JBB supported by AFRL/RW AF FA8651-10-1-0004 & DTRA, HDTRA1-10-1-0020 Off Campus. FMN's work supported by the U.S. DOE/ LLNL, Contract DE-AC52-07NA27344. LLNL-ABS-491794.

Unexpected angular or rotational deformity after corrective osteotomy

PubMed Central

2014-01-01

Background Codman’s paradox reveals a misunderstanding of geometry in orthopedic practice. Physicians often encounter situations that cannot be understood intuitively during orthopedic interventions such as corrective osteotomy. Occasionally, unexpected angular or rotational deformity occurs during surgery. This study aimed to draw the attention of orthopedic surgeons toward the concepts of orientation and rotation and demonstrate the potential for unexpected deformity after orthopedic interventions. This study focused on three situations: shoulder arthrodesis, femoral varization derotational osteotomy, and femoral derotation osteotomy. Methods First, a shoulder model was generated to calculate unexpected rotational deformity to demonstrate Codman’s paradox. Second, femoral varization derotational osteotomy was simulated using a cylinder model. Third, a reconstructed femoral model was used to calculate unexpected angular or rotational deformity during femoral derotation osteotomy. Results Unexpected external rotation was found after forward elevation and abduction of the shoulder joint. In the varization and derotation model, closed-wedge osteotomy and additional derotation resulted in an unexpected extension and valgus deformity, namely, under-correction of coxa valga. After femoral derotational osteotomy, varization and extension of the distal fragment occurred, although the extension was negligible. Conclusions Surgeons should be aware of unexpected angular deformity after surgical procedure involving bony areas. The degree of deformity differs depending on the context of the surgical procedure. However, this study reveals that notable deformities can be expected during orthopedic procedures such as femoral varization derotational osteotomy. PMID:24886469

Preferred orientation in experimentally deformed stishovite: implications for deformation mechanisms

DOE PAGES

Kaercher, Pamela M.; Zepeda-Alarcon, Eloisa; Prakapenka, Vitali B.; ...

2014-11-07

Although the crystal structure of the high pressure SiO 2 polymorph stishovite has been studied in detail, little is known about the development of crystallographic preferred orientation (CPO) during deformation in stishovite. Insight into CPO and associated deformation mechanics of stishovite would provide important information for understanding subduction of quartz-bearing crustal rocks into the mantle. To study CPO development, we converted a natural sample of flint to stishovite in a laser heated diamond anvil cell and compressed the stishovite aggregate up to 38 GPa. We collected diffraction patterns in radial geometry to examine in situ development of crystallographic preferred orientationmore » and find that (001) poles preferentially align with the compression direction. Viscoplastic self-consistent modeling suggests the most likely slip systems at high pressure and ambient temperature are pyramidal and basal slip.« less

Profil anatomopathologique du cancer du sein dans le cap bon tunisien

PubMed Central

Sahraoui, Ghada; Khanchel, Fatma; Chelbi, Emna

2017-01-01

Le cancer du sein est le cancer le plus fréquent de la femme en Tunisie et dans le monde. Dans le Cap Bon tunisien, les particularités anatomopathologiques de ce cancer n'ont pas été précisées auparavant. Leur connaissance est nécessaire pour l'adaptation des systèmes de prévention et de soins dans la région. Le but de notre étude était de déterminer le profil anatomopathologique des carcinomes mammaires dans l'unique laboratoire d'anatomie pathologique publique de la région. Il s'agissait d'une étude descriptive rétrospective des carcinomes mammaires diagnostiqués chez 116 malades dans notre laboratoire sur une période de 5 ans de Juillet 2010 à Juillet 2015. Notre étude a inclus 116 patientes. L'âge moyen était de 51 ans. La taille tumorale histologique moyenne était de 31 mm. Le diagnostic initial était posé sur pièce de tumorectomie dans 83% des cas. Le carcinome infiltrant de type non spécifique était le type histologique le plus fréquent. Le grade SBR III était majoritaire. L'invasion lympho-vasculaire était présente dans 33% des cas. Le curage axillaire était positif dans 72% des cas. Les récepteurs hormonaux étaient positifs dans 73% des cas. Les récepteurs de l'Her2-Neu étaient surexprimés dans 19% des cas. Le ki67 était ≥ 14% dans 38%. Le sous-type moléculaire le plus fréquent était le luminal A. Le carcinome mammaire dans la région du Cap Bon se caractérise par sa survenue à un âge jeune, son importante taille tumorale et la fréquence de facteurs histopronostiques péjoratifs. PMID:28450990

Pollybeak Deformity in Middle Eastern Rhinoplasty: Prevention and Treatment.

PubMed

Hussein, Wael K A; Foda, Hossam M T

2016-08-01

The pollybeak deformity is one of the commonest causes of revision rhinoplasty. The Middle Eastern nose has certain criteria that predispose to the development of pollybeak deformity. The aim of this study is to detect the factors contributing to the development of pollybeak deformity in the Middle Eastern nose and methods used to prevent as well as to treat such deformity. Out of the 1,160 revision patients included in this study, 720 (62%) patients had a pollybeak deformity. The commonest contributing factors included underprojected tip with poor support in 490 (68%) patients, excessive supratip scarring in 259 (36%) patients, overresected bony dorsum in 202 (28%) patients, and high anterior septal angle in 173 (24%) patients. The methods used by the authors to treat the pollybeak deformity are described, along with the local steroid injection protocol used to guard against the recurrence of pollybeak deformity. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

Differential calculus and gauge transformations on a deformed space

NASA Astrophysics Data System (ADS)

Wess, Julius

2007-08-01

We consider a formalism by which gauge theories can be constructed on noncommutative space time structures. The coordinates are supposed to form an algebra, restricted by certain requirements that allow us to realise the algebra in terms of star products. In this formulation it is useful to define derivatives and to extend the algebra of coordinates by these derivatives. The elements of this extended algebra are deformed differential operators. We then show that there is a morphism between these deformed differential operators and the usual higher order differential operators acting on functions of commuting coordinates. In this way we obtain deformed gauge transformations and a deformed version of the algebra of diffeomorphisms. The deformation of these algebras can be clearly seen in the category of Hopf algebras. The comultiplication will be twisted. These twisted algebras can be realised on noncommutative spaces and allow the construction of deformed gauge theories and deformed gravity theory.

1. Historic American Buildings Survey, drawn by Pierre du Simitiere ...

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

1. Historic American Buildings Survey, drawn by Pierre du Simitiere (papers in Philadelphia Library) DRAWING OF REDWOOD LIBRARY IN 1768. - Redwood Library, 50 Bellevue Avenue, Newport, Newport County, RI

Etude de facteurs de risque de la transmission du VIH de la mère à l'enfant dans la stratégie « option A » à Lubumbashi, République Démocratique du Congo

PubMed Central

Ngwej, Dieudonné Tshikwej; Mukuku, Olivier; Mudekereza, Rachel; Karaj, Eugénie; Odimba, Etienne Bwana Fwamba; Luboya, Oscar Numbi; Kakoma, Jean-Baptiste Sakatolo; Wembonyama, Stanis Okitotshio

2015-01-01

Introduction L'infection à VIH chez la femme enceinte a pour principal risque la contamination du nouveau-né. L'objectif est de déterminer le taux de transmission du VIH de la mère à l'enfant (TME) dans la ville de Lubumbashi et en évaluer les facteurs de risque. Méthodes Il s'agissait d'une étude prospective transversale à visée analytique de 157 accouchées séropositives au VIH et de leurs enfants dans 12 structures sanitaires de Lubumbashi (RDCongo) du 1er octobre 2012 au 31 décembre 2013. Les paramètres sociodémographiques, cliniques et les données relatives aux activités de PTME du VIH ont été étudiés. Les statistiques usuelles ont été utilisées pour analyser les résultats. Le seuil de significativité a été fixé à une valeur de p < 0,05. Résultats Le taux de transmission verticale du VIH était de 12,7% (20/157). Il n'y avait pas d'association significative entre les caractéristiques sociodémographiques maternelles telles que l’âge, la parité, le niveau d’étude, la profession et l’état-civil et la TME (p>0,05). La transmission verticale du VIH était significativement associée aux facteurs suivants: le stade clinique 3 de l'OMS (OR=5,18 (1,5-18,1)), la présence d'infection opportuniste (OR=8,7 (2,7-27,8)), le dépistage lors de l'accouchement (OR=6,3 (1,0-39,0)) ou au cours de l'allaitement (OR=7,1 (1,1-76,7)), au taux de CD4 maternel <350/mm3 (OR=2,9 (1,1-7,7)), l'absence de thérapie antirétrovirale chez la mère (OR=19,9 (4,8-81,9)), la naissance avant terme (OR=4,7 (1,4-16,0)), la rupture prématurée de membranes (OR=45,0 (7,4-454,6)), le faible poids de naissance (OR=5,6 (1,9-16,7)), la notion de réanimation néonatale (OR=12,4 (3,8-40,1)), la non administration de la névirapine à la naissance (OR=26,4 (7,6-92,3)) et l'alimentation mixte (OR=12,6 (1,3-115,9)). Le sexe du nourrisson et le mode d'accouchement n’étaient pas non plus associés à la transmission verticale du VIH (p>0,05). Conclusion Le taux

Mechanisms of strain accommodation in plastically-deformed zircon under simple shear deformation conditions during amphibolite-facies metamorphism

NASA Astrophysics Data System (ADS)

Kovaleva, Elizaveta; Klötzli, Urs; Wheeler, John; Habler, Gerlinde

2018-02-01

This study documents the strain accommodation mechanisms in zircon under amphibolite-facies metamorphic conditions in simple shear. Microstructural data from undeformed, fractured and crystal-plastically deformed zircon crystals are described in the context of the host shear zone, and evaluated in the light of zircon elastic anisotropy. Our work challenges the existing model of zircon evolution and shows previously undescribed rheological characteristics for this important accessory mineral. Crystal-plastically deformed zircon grains have axis oriented parallel to the foliation plane, with the majority of deformed grains having axis parallel to the lineation. Zircon accommodates strain by a network of stepped low-angle boundaries, formed by switching between tilt dislocations with the slip systems <100>{010} and < 1 bar 10>{110} and rotation axis [001], twist dislocations with the rotation axis [001], and tilt dislocations with the slip system <100>{001} and rotation axis [010]. The slip system < 1 bar 10>{110} is newly described for zircon. Most misorientation axes in plastically-deformed zircon grains are parallel to the XY plane of the sample and have [001] crystallographic direction. Such behaviour of strained zircon lattice is caused by elastic anisotropy that has a direct geometric control on the rheology, deformation mechanisms and dominant slip systems in zircon. Young's modulus and P wave velocity have highest values parallel to zircon [001] axis, indicating that zircon is elastically strong along this direction. Poisson ratio and Shear modulus demonstrate that zircon is also most resistant to shearing along [001]. Thus, [001] axis is the most common rotation axis in zircon. The described zircon behaviour is important to take into account during structural and geochronological investigations of (poly)metamorphic terrains. Geometry of dislocations in zircon may help reconstructing the geometry of the host shear zone(s), large-scale stresses in the

Foam rheology at large deformation

NASA Astrophysics Data System (ADS)

Géminard, J.-C.; Pastenes, J. C.; Melo, F.

2018-04-01

Large deformations are prone to cause irreversible changes in materials structure, generally leading to either material hardening or softening. Aqueous foam is a metastable disordered structure of densely packed gas bubbles. We report on the mechanical response of a foam layer subjected to quasistatic periodic shear at large amplitude. We observe that, upon increasing shear, the shear stress follows a universal curve that is nearly exponential and tends to an asymptotic stress value interpreted as the critical yield stress at which the foam structure is completely remodeled. Relevant trends of the foam mechanical response to cycling are mathematically reproduced through a simple law accounting for the amount of plastic deformation upon increasing stress. This view provides a natural interpretation to stress hardening in foams, demonstrating that plastic effects are present in this material even for minute deformation.

Miners, masculinity and the "Bataille du Charbon" in France, 1944-1948.

PubMed

Diamond, Hanna

2011-01-01

In 1944, the French provisional government, backed by the Parti communiste français and the Confédération générale du travail, undertook an aggressive propaganda campaign to persuade miners to embark upon a 'battle for coal' which raised their efforts in extracting coal to that of a national endeavour. At the same time, miners had great hopes that nationalisation of the coal industry, under discussion at this time, would bring significant improvement to their working lives. In identifying the ways in which publicists posited miners as an ideal of working-class manhood, this article will argue that "la bataille du charbon" marks a crucial moment in the celebration of working-class masculinity and that the "statut des mineurs" which was passed in 1946 as a part of nationalisation enshrined many of the existing gender assumptions about mining life. What does an incorporation of gender to an analysis of the treatment of miners in the years 1944-1948 add to our understandings of the various economic, political and social dynamics around "la bataille du charbon"? How do these insights inform our perceptions of French coalfield societies in the mid-twentieth century?

Syn-deformational features of Carlin-type Au deposits

USGS Publications Warehouse

Peters, S.G.

2004-01-01

Syn-deformational ore deposition played an important role in some Carlin-type Au deposits according to field and laboratory evidence, which indicates that flow of Au-bearing fluids was synchronous with regional-scale deformation events. Gold-related deformation events linked to ore genesis were distinct from high-level, brittle deformation that is typical of many epithermal deposits. Carlin-type Au deposits, with brittle-ductile features, most likely formed during tectonic events that were accompanied by significant fluid flow. Interactive deformation-fluid processes involved brittle-ductile folding, faulting, shearing, and gouge development that were focused along illite-clay and dissolution zones caused by hydrothermal alteration. Alteration along these deformation zones resulted in increased porosity and enhancement of fluid flow, which resulted in decarbonated, significant dissolution, collapse, and volume and mass reduction. Carlin-type Au deposits commonly are hosted in Paleozoic and Mesozoic sedimentary rocks (limestone, siltstone, argillite, shale, and quartzite) on the margins of cratons. The sedimentary basins containing the host rocks underwent tectonic events that influenced the development of stratabound, structurally controlled orebodies. Published by Elsevier Ltd.

Deformation cycles of subduction earthquakes in a viscoelastic Earth.

PubMed

Wang, Kelin; Hu, Yan; He, Jiangheng

2012-04-18

Subduction zones produce the largest earthquakes. Over the past two decades, space geodesy has revolutionized our view of crustal deformation between consecutive earthquakes. The short time span of modern measurements necessitates comparative studies of subduction zones that are at different stages of the deformation cycle. Piecing together geodetic 'snapshots' from different subduction zones leads to a unifying picture in which the deformation is controlled by both the short-term (years) and long-term (decades and centuries) viscous behaviour of the mantle. Traditional views based on elastic models, such as coseismic deformation being a mirror image of interseismic deformation, are being thoroughly revised.

Race towards Freedom: W.E.B. Du Bois and the Tradition of Fugitive Black Study

ERIC Educational Resources Information Center

Tinson, Christopher M.

2017-01-01

This essay centers the defense of black educational possibility in the work of historian, pioneering sociologist, and scholar, W.E.B. Du Bois (1868-1963) as a conduit igniting what critical social theorists Stefano Harney and Fred Moten (2013) call Fugitive Black Study. The critical appreciation of Du Bois forces us to consider the weight of…

Analyse de la dégradation thermique du Poly(éther éther cétone)

NASA Astrophysics Data System (ADS)

Courvoisier, Emilie; Bicaba, Yoann; Colin, Xavier

2018-03-01

La dégradation thermique du PEEK a été étudiée à l'état caoutchoutique dans de larges intervalles de température (entre 180 et 320 °C) et de pression partielle d'oxygène (entre 0,21 et 50 bars). Tout d'abord, les mécanismes de vieillissement thermique ont été analysés et élucidés par spectroscopie IRTF et par calorimétrie différentielle (DSC) sur des films de PEEK suffisamment minces (entre 10 et 60 μm d'épaisseur) pour s'affranchir totalement des effets de la diffusion d'oxygène. L'oxydation se produit sur les cycles aromatiques provoquant la croissance de cinq nouvelles bandes d'absorption IR centrées à 3650, 3525, 1780, 1740 et 1718 cm-1 et attribuées aux vibrations d'élongation des liaisons O-H du phénol et de l'acide benzoïque, et des liaisons C-O de l'anhydride benzoïque, du benzoate de phényle et de la fluorénone respectivement. De plus, l'oxydation conduit à une large prédominance de la réticulation sur les coupures de chaîne (augmentation de Tg) empêchant le recuit du PEEK, en particulier lorsque la température d'exposition est supérieure au pied du pic de fusion. Enfin, les conséquences de l'oxydation sur les propriétés élastiques ont été analysées et élucidées par micro-indentation sur des sections droites préalablement polies de plaquettes de PEEK de 3 mm d'épaisseur. Les variations du module d'Young et du taux de cristallinité se corrèlent parfaitement, vérifiant ainsi la relation de Tobolsky.

Partial purification and characterization of bacteriocin produced by Enterococcus faecalis DU10 and its probiotic attributes.

PubMed

Perumal, Venkatesh; Repally, Ayyanna; Dasari, Ankaiah; Venkatesan, Arul

2016-10-02

A novel bacteriocin produced by avian duck isolated lactic acid bacterium Enterococcus faecalis DU10 was isolated. This bacteriocin showed a broad spectrum of antibacterial activity against important food-borne pathogens and was purified by size exclusion chromatography followed by reverse-phase high-performance liquid chromatography in a C-18 column. Tricine-SDS PAGE revealed the presence of a band with an estimated molecular mass of 6.3 kDa. The zymogram clearly linked the antimicrobial activity with this band. This result was further confirmed by mass-assisted laser desorption ionization time-of-flight mass spectrometry, since a sharp peak corresponding to 6.313 kDa was detected and the functional groups were revealed by Fourier transform infrared spectroscopy. Bacteriocin DU10 activity was found sensitive to proteinase-K and pepsin and partially affected by trypsin and α-chymotrypsin. The activity of bacteriocin DU10 was partially resistant to heat treatments ranging from 30 to 90°C for 30 min. It also withstood a treatment at 121°C for 10 min. Cytotoxicity of bacteriocin DU10 by methyl-thiazolyl-diphenyl-tetrazolium bromide assay showed that the viability of HT-29 and HeLa cells decreased 60 ± 0.7% and 43 ± 4.8%, respectively, in the presence of 3,200 AU/mL of bacteriocin. The strain withstood 0.3% w/v of bile oxgall and pH 2 affected the bacterial growth between 2 and 4 hr of incubation. Adhesion properties examined with HT-29 cell line showed 69.85% initial population of strain E. faecalis DU10, which was found to be strongly adhered to this cell line. These results conclude bacteriocin DU10 may be used as a potential biopreservative and E. faecalis DU10 may be used as a potential probiont to control Salmonella infections.

Dysplasie fibreuse polyostotique unilatérale du membre supérieur

PubMed Central

Boufettal, Monsef; Azouz, Mohamed; Mahfoud, Mustapha; El Bardouni, Ahmed; Berrada, Mohamed Saleh; El Yaacoubi, Moradh

2014-01-01

La dysplasie fibreuse est une maladie osseuse sporadique rare d’étiologie inconnue qui représente environ 2,5% des maladies osseuses et 7% des tumeurs osseuses bénignes. Cette lésion bénigne pseudotumorale se caractérise par la présence dans l'os d'une prolifération de tissu fibreux et de tissu osseux immature dépourvu de couronne ostéoblastique. Elle peut atteindre un ou plusieurs os; l'atteinte du membre supérieur est rarement décrite, nous rapportons ici un cas rare de dysplasie fibreuse polyostotique unilatérale du membre supérieure. PMID:25709739

Surface dislocation nucleation controlled deformation of Au nanowires

DOE Office of Scientific and Technical Information (OSTI.GOV)

Roos, B.; Kapelle, B.; Volkert, C. A., E-mail: volkert@ump.gwdg.de

2014-11-17

We investigate deformation in high quality Au nanowires under both tension and bending using in-situ transmission electron microscopy. Defect evolution is investigated during: (1) tensile deformation of 〈110〉 oriented, initially defect-free, single crystal nanowires with cross-sectional widths between 30 and 300 nm, (2) bending deformation of the same wires, and (3) tensile deformation of wires containing coherent twin boundaries along their lengths. We observe the formation of twins and stacking faults in the single crystal wires under tension, and storage of full dislocations after bending of single crystal wires and after tension of twinned wires. The stress state dependence of themore » deformation morphology and the formation of stacking faults and twins are not features of bulk Au, where deformation is controlled by dislocation interactions. Instead, we attribute the deformation morphologies to the surface nucleation of either leading or trailing partial dislocations, depending on the Schmid factors, which move through and exit the wires producing stacking faults or full dislocation slip. The presence of obstacles such as neutral planes or twin boundaries hinder the egress of the freshly nucleated dislocations and allow trailing and leading partial dislocations to combine and to be stored as full dislocations in the wires. We infer that the twins and stacking faults often observed in nanoscale Au specimens are not a direct size effect but the result of a size and obstacle dependent transition from dislocation interaction controlled to dislocation nucleation controlled deformation.« less

The minimally invasive spinal deformity surgery algorithm: a reproducible rational framework for decision making in minimally invasive spinal deformity surgery.

PubMed

Mummaneni, Praveen V; Shaffrey, Christopher I; Lenke, Lawrence G; Park, Paul; Wang, Michael Y; La Marca, Frank; Smith, Justin S; Mundis, Gregory M; Okonkwo, David O; Moal, Bertrand; Fessler, Richard G; Anand, Neel; Uribe, Juan S; Kanter, Adam S; Akbarnia, Behrooz; Fu, Kai-Ming G

2014-05-01

Minimally invasive surgery (MIS) is an alternative to open deformity surgery for the treatment of patients with adult spinal deformity. However, at this time MIS techniques are not as versatile as open deformity techniques, and MIS techniques have been reported to result in suboptimal sagittal plane correction or pseudarthrosis when used for severe deformities. The minimally invasive spinal deformity surgery (MISDEF) algorithm was created to provide a framework for rational decision making for surgeons who are considering MIS versus open spine surgery. A team of experienced spinal deformity surgeons developed the MISDEF algorithm that incorporates a patient's preoperative radiographic parameters and leads to one of 3 general plans ranging from MIS direct or indirect decompression to open deformity surgery with osteotomies. The authors surveyed fellowship-trained spine surgeons experienced with spinal deformity surgery to validate the algorithm using a set of 20 cases to establish interobserver reliability. They then resurveyed the same surgeons 2 months later with the same cases presented in a different sequence to establish intraobserver reliability. Responses were collected and tabulated. Fleiss' analysis was performed using MATLAB software. Over a 3-month period, 11 surgeons completed the surveys. Responses for MISDEF algorithm case review demonstrated an interobserver kappa of 0.58 for the first round of surveys and an interobserver kappa of 0.69 for the second round of surveys, consistent with substantial agreement. In at least 10 cases there was perfect agreement between the reviewing surgeons. The mean intraobserver kappa for the 2 surveys was 0.86 ± 0.15 (± SD) and ranged from 0.62 to 1. The use of the MISDEF algorithm provides consistent and straightforward guidance for surgeons who are considering either an MIS or an open approach for the treatment of patients with adult spinal deformity. The MISDEF algorithm was found to have substantial inter- and

Fentes labiopalatines dans la province du Katanga en République Démocratique du Congo: Aspects épidémiologiques, anatomocliniques et thérapeutiques

PubMed Central

Sangwa, Cedrick Milindi; Mukuku, Olivier; Tshisuz, Christian; Panda, Jules Mulefu; Kakinga, Mireille; Kitembo, Marius Feruzi; Mutomb, Jean-Felix; Odimba, Bwana Fwamba

2014-01-01

Les fentes labiopalatines sont les malformations les plus rencontrées de la sphère orofaciale. L'objectif est de décrire le profil épidémiologique, anatomoclinique et thérapeutique des fentes labiopalatines observées dans la province minière du Katanga au sud-est de la République Démocratique du Congo. Il s'agit d'une étude transversale réalisée dans quatre institutions hospitalières de la province du Katanga dans des districts sanitaires différents (Hôpital Jason Sendwe à Lubumbashi, Hôpital Gécamines Panda à Likasi, Hôpital Gécamines du personnel à Kolwezi, Hôpital General de référence de Kamina) et qui a porté sur 154 cas de fentes labiopalatines enregistrés au cours de la période allant du 1er mai 2010 au 30 septembre 2012. L'âge moyen de consultation était de 11,8 ans et une prédominance masculine (55,2%) était notée. Un pic était noté chez les deux premiers nés de la famille (55,8%). Nous avons enregistré 20,7% des cas de consanguinité dont 54,2% de premier degré. La fréquence des différents types de fentes labiopalatines diminue au fur à mesure que la fente s'étend de la lèvre supérieure au palais en passant par l'alvéole : 72% (labiales), 21,4% (labiopalatines) et 7,7% (palatines). Les variétés unilatérales sont plus fréquentes (76,7%) que les bilatérales (16,1%). Dans les formes unilatérales, le côté gauche est plus concerné (47,1%) par rapport au côté droit (38,6%). L'évaluation de la gravité selon Anastassov montre que 50,6% de nos patients étaient de degré moyen et 16,2% étaient à un degré sévère. Les malformations associées ont été retrouvées dans 5% des cas et elles sont à prédominance squelettique. C'est la technique de Millard qui a été la plus pratiquée (72/130). Les résultats étaient excellents dans 71,5% contre 1,5% de mauvais. Le séjour d'hospitalisation était de 3 jours et le taux de complications post opératoire était de 2,98%. PMID:25328615

Deformation mechanisms of nanotwinned Al

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhang, Xinghang

The objective of this project is to investigate the role of different types of layer interfaces on the formation of high density stacking fault (SF) in Al in Al/fcc multilayers, and understand the corresponding deformation mechanisms of the films. Stacking faults or twins can be intentionally introduced (via growth) into certain fcc metals with low stacking fault energy (such as Cu, Ag and 330 stainless steels) to achieve high strength, high ductility, superior thermal stability and good electrical conductivity. However it is still a major challenge to synthesize these types of defects into metals with high stacking fault energy, suchmore » as Al. Although deformation twins have been observed in some nanocrystalline Al powders by low temperature, high strain rate cryomilling or in Al at the edge of crack tip or indentation (with the assistance of high stress intensity factor), these deformation techniques typically introduce twins sporadically and the control of deformation twin density in Al is still not feasible. This project is designed to test the following hypotheses: (1) Certain type of layer interfaces may assist the formation of SF in Al, (2) Al with high density SF may have deformation mechanisms drastically different from those of coarse-grained Al and nanotwinned Cu. To test these hypotheses, we have performed the following tasks: (i) Investigate the influence of layer interfaces, stresses and deposition parameters on the formation and density of SF in Al. (ii) Understand the role of SF on the deformation behavior of Al. In situ nanoindentation experiments will be performed to probe deformation mechanisms in Al. The major findings related to the formation mechanism of twins and mechanical behavior of nanotwinned metals include the followings: 1) Our studies show that nanotwins can be introduced into metals with high stacking fault energy, in drastic contrast to the general anticipation. 2) We show two strategies that can effectively introduce growth

Localization in Naturally Deformed Systems - the Default State?

NASA Astrophysics Data System (ADS)

Clancy White, Joseph

2017-04-01

Based on the extensive literature on localized rock deformation, conventional wisdom would interpret it to be a special behaviour within an anticipated background of otherwise uniform deformation. The latter notwithstanding, the rock record is so rife with transient (cyclic), heterogeneous deformation, notably shear localization, as to characterize localization as the anticipated 'normal' behaviour. The corollary is that steady, homogeneous deformation is significantly less common, and if achieved must reflect some special set of conditions that are not representative of the general case. An issue central to natural deformation is then not the existance of localized strain, but rather how the extant deformation processes scale across tectonic phenomena and in turn organize to enable a coherent(?) descripion of Earth deformation. Deformation is fundamentally quantized, discrete (diffusion, glide, crack propagation) and reliant on the defect state of rock-forming minerals. The strain energy distribution that drives thermo-mechanical responses is in the first instance established at the grain-scale where the non-linear interaction of defect-mediated micromechanical processes introduces heterogeneous behaviour described by various gradient theories, and evidenced by the defect microstructures of deformed rocks. Hence, the potential for non-uniform response is embedded within even quasi-uniform, monomineralic materials, seen, for example, in the spatially discrete evolution of dynamic recrystallization. What passes as homogeneous or uniform deformation at various scales is the aggregation of responses at some characteristic dimension at which heterogeneity is not registered or measured. Nevertheless, the aggregate response and associated normalized parameters (strain, strain rate) do not correspond to any condition actually experienced by the deforming material. The more common types of macroscopic heterogeneity promoting localization comprise mechanically contrasting

Study on optical 3D angular deformations measurement

NASA Astrophysics Data System (ADS)

Gao, Yang; Wang, Xingshu; Huang, Zongsheng; Yang, Jinliang

2013-12-01

3D angular deformations will be inevitable when ships are sailing, due to the changes of the environmental temperature and external stresses. The measurement of 3D angular deformations is one of the most critical and difficult issues in navy and shipbuilding industry around the world. In this paper, we propose an optical method to measure 3D ship angular deformations and discuss the measurement errors in detail. Theoretical analysis shows that the measured errors of the pitching and yawing deformations are induced by the installation errors of the image aperture, and the measured error of the rolling deformation depends on the subpixel location algorithm in image processing. It indicates that the measured errors of the optical measurement proposed in this paper are at the magnitude of angular seconds, when the elaborated installation and precise image processing technology are both performed.

Correcting for deformation in skin-based marker systems.

PubMed

Alexander, E J; Andriacchi, T P

2001-03-01

A new technique is described that reduces error due to skin movement artifact in the opto-electronic measurement of in vivo skeletal motion. This work builds on a previously described point cluster technique marker set and estimation algorithm by extending the transformation equations to the general deformation case using a set of activity-dependent deformation models. Skin deformation during activities of daily living are modeled as consisting of a functional form defined over the observation interval (the deformation model) plus additive noise (modeling error). The method is described as an interval deformation technique. The method was tested using simulation trials with systematic and random components of deformation error introduced into marker position vectors. The technique was found to substantially outperform methods that require rigid-body assumptions. The method was tested in vivo on a patient fitted with an external fixation device (Ilizarov). Simultaneous measurements from markers placed on the Ilizarov device (fixed to bone) were compared to measurements derived from skin-based markers. The interval deformation technique reduced the errors in limb segment pose estimate by 33 and 25% compared to the classic rigid-body technique for position and orientation, respectively. This newly developed method has demonstrated that by accounting for the changing shape of the limb segment, a substantial improvement in the estimates of in vivo skeletal movement can be achieved.

Quantum deformations of conformal algebras with mass-like deformation parameters

DOE Office of Scientific and Technical Information (OSTI.GOV)

Frydryszak, Andrzej; Lukierski, Jerzy; Mozrzymas, Marek

1998-12-15

We recall the mathematical apparatus necessary for the quantum deformation of Lie algebras, namely the notions of coboundary Lie algebras, classical r-matrices, classical Yang-Baxter equations (CYBE), Froebenius algebras and parabolic subalgebras. Then we construct the quantum deformation of D=1, D=2 and D=3 conformal algebras, showing that this quantization introduce fundamental mass parameters. Finally we consider with more details the quantization of D=4 conformal algebra. We build three classes of sl(4,C) classical r-matrices, satisfying CYBE and depending respectively on 8, 10 and 12 generators of parabolic subalgebras. We show that only the 8-dimensional r-matrices allow to impose the D=4 conformal o(4,2){approx_equal}su(2,2)more » reality conditions. Weyl reflections and Dynkin diagram automorphisms for o(4,2) define the class of admissible bases for given classical r-matrices.« less

Imaging of congenital chest wall deformities

PubMed Central

Bhaludin, Basrull N; Naaseri, Sahar; Di Chiara, Francesco; Jordan, Simon; Padley, Simon

2016-01-01

To identify the anatomy and pathology of chest wall malformations presenting for consideration for corrective surgery or as a possible chest wall “mass”, and to review the common corrective surgical procedures. Congenital chest wall deformities are caused by anomalies of chest wall growth, leading to sternal depression or protrusion, or are related to failure of normal spine or rib development. Cross-sectional imaging allows appreciation not only of the involved structures but also assessment of the degree of displacement or deformity of adjacent but otherwise normal structures and differentiation between anatomical deformity and neoplasia. In some cases, CT is also useful for surgical planning. The use of three-dimensional reconstructions, utilizing a low-dose technique, provides important information for the surgeon to discuss the nature of anatomical abnormalities and planned corrections with the patient and often with their parents. In this pictorial essay, we discuss the radiological features of the commonest congenital chest wall deformities and illustrate pre- and post-surgical appearances for those undergoing surgical correction. PMID:26916279

Paleohydrologic controls on soft-sediment deformation in the Navajo Sandstone

NASA Astrophysics Data System (ADS)

Bryant, Gerald; Cushman, Robert; Nick, Kevin; Miall, Andrew

2016-10-01

Many workers have noted the presence of contorted cross-strata in the Navajo Sandstone and other ancient eolianites, and have recognized their significance as indicators of sediment saturation during the accumulation history. Horowitz (1982) proposed a general model for the production of such features in ancient ergs by episodic, seismically induced liquefaction of accumulated sand. A key feature of that popular model is the prevalence of a flat water table, characteristic of a hyper-arid climatic regime, during deformation. Under arid climatic conditions, the water table is established by regional flow and liquefaction is limited to the saturated regions below the level of interdune troughs. However, various paleohydrological indicators from Navajo Sandstone outcrops point toward a broader range of water table configurations during the deformation history of that eolianite. Some outcrops reveal extensive deformation complexes that do not appear to have extended to the contemporary depositional surface. These km-scale zones of deformation, affecting multiple sets of cross-strata, and grading upward into undeformed crossbeds may represent deep water table conditions, coupled with high intensity triggers, which produced exclusively intrastratal deformation. Such occurrences contrast with smaller-scale complexes formed within the zone of interaction between the products of soft-sediment deformation and surface processes of deposition and erosion. The Horowitz model targets the smaller-scale deformation morphologies produced in this near-surface environment. This study examines the implications of a wet climatic regime for the Horowitz deformation model. It demonstrates how a contoured water table, characteristic of humid climates, may have facilitated deformation within active bedforms, as well as in the accumulation. Intra-dune deformation would enable deflation of deformation features during the normal course of dune migration, more parsimoniously accounting for

Deformation processes in forging ceramics

NASA Technical Reports Server (NTRS)

Cannon, R. M.; Rhodes, W. H.

1973-01-01

The deformation processes involved in the forging of refractory ceramic oxides were investigated. A combination of mechanical testing and forging was utilized to investigate both the flow and fracture processes involved. Deformation studies of very fine grain Al203 revealed an apparent transition in behavior, characterized by a shift in the strain rate sensitivity from 0.5 at low stresses to near unity at higher stresses. The behavior is indicative of a shift in control between two dependent mechanisms, one of which is indicated to be cation limited diffusional creep with significant boundary enhancement. The possible contributions of slip, indicated by crystallographic texture, interface control of the diffusional creep and inhomogeneous boundary sliding are also discussed. Additional experiments indicated an independence of deformation behavior on MgO doping and retained hot pressing impurities, at least for ultrafine grained material, and also an independence of test atmosphere.

Transport diffusion in deformed carbon nanotubes

NASA Astrophysics Data System (ADS)

Feng, Jiamei; Chen, Peirong; Zheng, Dongqin; Zhong, Weirong

2018-03-01

Using non-equilibrium molecular dynamics and Monte Carlo methods, we have studied the transport diffusion of gas in deformed carbon nanotubes. Perfect carbon nanotube and various deformed carbon nanotubes are modeled as transport channels. It is found that the transport diffusion coefficient of gas does not change in twisted carbon nanotubes, but changes in XY-distortion, Z-distortion and local defect carbon nanotubes comparing with that of the perfect carbon nanotube. Furthermore, the change of transport diffusion coefficient is found to be associated with the deformation factor. The relationship between transport diffusion coefficient and temperature is also discussed in this paper. Our results may contribute to understanding the mechanism of molecular transport in nano-channel.

The thermal and mechanical deformation study of up-stream pumping mechanical seal

NASA Astrophysics Data System (ADS)

Chen, H. L.; Xu, C.; Zuo, M. Z.; Wu, Q. B.

2015-01-01

Taking the viscosity-temperature relationship of the fluid film into consideration, a 3-D numerical model was established by ANSYS software which can simulate the heat transfer between the upstream pumping mechanical seal stationary and rotational rings and the fluid film between them as well as simulate the thermal deformation, structure deformation and the coupling deformation of them. According to the calculation result, thermal deformation causes the seal face expansion and the maximum thermal deformation appears at the inside of the seal ring. Pressure results in a mechanical deformation, the maximum deformation occurs at the top of the spiral groove and the overall trend is inward the mating face, opposite to the thermal deformation. The coupling deformation indicate that the thermal deformation can be partly counteracted by pressure deformation. Using this model, the relationship between deformation and shaft speed and the sealing liquid pressure was studied. It's found that the shaft speed will both enhance the thermal and structure deformation and the fluid pressure will enhance the structure deformation but has little to do with the thermal deformation. By changing the sealing material, it's found that material with low thermal expansion coefficient and low elastic modulus will suffer less thermal-pressure deformation.

The DuPont Conference: Implications for the Chemical Technology Curriculum

NASA Astrophysics Data System (ADS)

Kenkel, John; Rutledge, Sue; Kelter, Paul B.

1998-05-01

Southeast Community College (SCC) hosted the first DuPont Conference for Chemical Technology Education at its Lincoln, Nebraska campus October 4-6, 1997. The conference brought together fourteen practicing chemists and chemistry technicians and five college and university faculty members for the express purpose of suggesting new laboratory activities that would help relate the real world of work to the education of chemical laboratory technicians in community colleges. Participants included seven men and seven women from DuPont, Procter & Gamble, Eastman Chemical, Eastman Kodak, Dow Chemical, Air Products and Chemicals, Monsanto, Union Carbide, the Nebraska Agriculture Laboratory, and the University of Nebraska Biological Process Development Facility, Department of Food Science. The conference, sponsored by the E. I. DuPont DeNemours & Company through a grant awarded to SCC in June 1997, was intended to help further the goals of the two major projects underway at SCC, funded by the National Science Foundation's Advanced Technological Education Program. These projects, dubbed "Assignment: Chemical Technology I and II", or ACT-I and ACT-II, are curriculum and materials development projects. The invited scientists had between 2 and 32 years of experience that ranged from bench work to management levels. Many are or have been active on the national scene as members and officers of the American Chemical Society's Division of Chemical Technicians and the ACS Committee on Technician Activities.

Dedicated Caravan Sites for French Gens du Voyage: Public Health Policy or Construction of Health and Environmental Inequalities?

PubMed

Foisneau, Lise

2017-12-01

In France, gens du voyage ("people who travel" or "travellers") is a term used by the government to categorize various itinerant populations, the majority of which are diverse Romani groups. People categorized as gens du voyage are legally required to reside in particular locations called "dedicated caravan sites." Parliamentary debates about these dedicated caravan sites have clarified that one of the objectives of such sites is to help fulfill the gens du voyage 's right to health. However, there is a significant gap between the officially stated goals of such sites and the reality of life within them. This paper draws on research finding that the conditions in most dedicated caravan sites do not conform with the rights of gens du voyage to acceptable sanitary conditions and other underlying determinants of health.

Guideline on Scenario Development for (Distributed) Simulation Environments (Guide en vue du developpement de scenario dans le cadre de simulation distribuee)

DTIC Science & Technology

2015-01-01

des lacunes de M&S du MORS du NMSG a déterminé que le manque d’interopérabilité de la simulation constituait la lacune prioritaire à combler en...matière de capacité, une équipe exploratoire (ET-027) a été constituée au sein du NMSG pour étudier l’interopérabilité de la simulation. L’ET-027 a...élevés (autrement dit, aux niveaux pratique, dynamique et conceptuel) de même que l’automatisation relative du développement, de

Deformation at Lava Lake Volcanoes: Lessons from Karthala

NASA Astrophysics Data System (ADS)

Biggs, J.; Rust, A.; Owens, C.

2014-12-01

To remain hot, permanent lava lakes require a continuous connection to a magma reservoir. Depending on the state of the conduit, changes in magma pressure could result in changes in the lake level (hydraulic head) or be accommodated elastically leading to surface deformation. Observing deformation is therefore key to understanding the plumbing system associated with lava lakes. However, the majority of the world's lava lakes lie in difficult socio-economic or remote locations meaning that there are few ground-based observations, and it is often necessary to rely on satellite imagery. Karthala volcano experienced a sequence of eruptions in April 2005, Nov 2005, May 2006 and Jan 2007. The first 3 took place at the Choungou Chahale crater, which typically contains either a water or lava lake; the last formed a new pit crater to the north. Satellite thermal imagery (Hirn et al, 2008) does not show an anomaly during the first eruption, which had a phreatomagmatic component, but large thermal anomalies, associated with an ephemeral lava lake were detected during the Nov 2005 and May 2006 eruptions. The final eruption produced a smaller anomaly attributed to a minor lava flow. Here we present InSAR observations from 2004-2010. We find no significant deformation associated with the first three eruptions, but the January 2007 eruption was associated with ~25 cm of deformation near the volcano's summit, characteristic of a dyke intrusion aligned with the northern rift zone. We also observe an unusual pattern deformation along the coast which may be attributed to rapid settling of soft sediment or recent volcanic deposits triggered by seismic activity. We propose that the first eruption cleared the reservoir-summit connection and interacted with the water in Choungou Chahale. The following eruptions formed a lava lake, but without causing deformation. By the final eruption, the conduit had become blocked and magma intruded along the rift zone causing deformation but no

Fibres Optiques En Therapie Laser Au Contact Du Tissu

NASA Astrophysics Data System (ADS)

Lenz, P.; Sabben, G.; Lambert, R.; Berger, F.

1984-03-01

Les fibres en quartz, non protegees par un courant de gaz et placees au contact du tissu, peuvent etre utilisees pratiquement indefiniment grace a un "autonettoyage" et une "regenera-tion". Elles provoquent des lesions tissulaires semblables a celles obtenues avec les fibres conventionnelles.

Equilibrium Droplets on Deformable Substrates: Equilibrium Conditions.

PubMed

Koursari, Nektaria; Ahmed, Gulraiz; Starov, Victor M

2018-05-15

Equilibrium conditions of droplets on deformable substrates are investigated, and it is proven using Jacobi's sufficient condition that the obtained solutions really provide equilibrium profiles of both the droplet and the deformed support. At the equilibrium, the excess free energy of the system should have a minimum value, which means that both necessary and sufficient conditions of the minimum should be fulfilled. Only in this case, the obtained profiles provide the minimum of the excess free energy. The necessary condition of the equilibrium means that the first variation of the excess free energy should vanish, and the second variation should be positive. Unfortunately, the mentioned two conditions are not the proof that the obtained profiles correspond to the minimum of the excess free energy and they could not be. It is necessary to check whether the sufficient condition of the equilibrium (Jacobi's condition) is satisfied. To the best of our knowledge Jacobi's condition has never been verified for any already published equilibrium profiles of both the droplet and the deformable substrate. A simple model of the equilibrium droplet on the deformable substrate is considered, and it is shown that the deduced profiles of the equilibrium droplet and deformable substrate satisfy the Jacobi's condition, that is, really provide the minimum to the excess free energy of the system. To simplify calculations, a simplified linear disjoining/conjoining pressure isotherm is adopted for the calculations. It is shown that both necessary and sufficient conditions for equilibrium are satisfied. For the first time, validity of the Jacobi's condition is verified. The latter proves that the developed model really provides (i) the minimum of the excess free energy of the system droplet/deformable substrate and (ii) equilibrium profiles of both the droplet and the deformable substrate.

Adiabatically describing rare earths using microscopic deformations

NASA Astrophysics Data System (ADS)

Nobre, Gustavo; Dupuis, Marc; Herman, Michal; Brown, David

2017-09-01

Recent works showed that reactions on well-deformed nuclei in the rare-earth region are very well described by an adiabatic method. This assumes a spherical optical potential (OP) accounting for non-rotational degrees of freedom while the deformed configuration is described by couplings to states of the g.s. rotational band. This method has, apart from the global OP, only the deformation parameters as inputs, with no additional fit- ted variables. For this reason, it has only been applied to nuclei with well-measured deformations. With the new computational capabilities, microscopic large-scale calculations of deformation parameters within the HFB method based on the D1S Gogny force are available in the literature. We propose to use such microscopic deformations in our adi- abatic method, allowing us to reproduce the cross sections agreements observed in stable nuclei, and to reliably extend this description to nuclei far from stability, describing the whole rare-earth region. Since all cross sections, such as capture and charge exchange, strongly depend on the correct calculation of absorption from the incident channel (from direct reaction mechanisms), this approach significantly improves the accuracy of cross sections and transitions relevant to astrophysical studies. The work at BNL was sponsored by the Office of Nuclear Physics, Office of Science of the US Department of Energy, under Contract No. DE-AC02-98CH10886 with Brookhaven Science Associates, LLC.

Active Beam Shaping System and Method Using Sequential Deformable Mirrors

NASA Technical Reports Server (NTRS)

Pueyo, Laurent A. (Inventor); Norman, Colin A. (Inventor)

2015-01-01

An active optical beam shaping system includes a first deformable mirror arranged to at least partially intercept an entrance beam of light and to provide a first reflected beam of light, a second deformable mirror arranged to at least partially intercept the first reflected beam of light from the first deformable mirror and to provide a second reflected beam of light, and a signal processing and control system configured to communicate with the first and second deformable mirrors. The first deformable mirror, the second deformable mirror and the signal processing and control system together provide a large amplitude light modulation range to provide an actively shaped optical beam.

Optical Deformability as New Diagnostic Cell Marker

NASA Astrophysics Data System (ADS)

Guck, Jochen; Lincoln, Bryan; Schinkinger, Stefan; Wottawah, Falk; Moore, Samantha; Ananthakrishnan, Revathi; Kas, Josef

2002-03-01

The optical stretcher is a novel laser tool that can deform individual cells in rapid succession. When a cell is trapped between two counterpropagating laser beams the optically induced surface forces stretch the cell along the laser axis. The degree of stretching depends on the optical properties, which determine the forces, as well as the mechanical properties, which govern the response of the cell to the forces. Our results show that different cells can be distinguished based on their optical deformability, which naturally suggests using the optical deformability of cells as a novel cell marker. Many diseases are reflected in an altered cytoskeleton, which leads to a different optical deformability. An important example is the malignant transformation of cells, which is accompanied by a decrease in cytoskeletal integrity and, consequently, cell elasticity. Using optical deformability as cell marker holds the promise of earlier detection and improved diagnosis of cancer. In this context, the optical stretcher can be used as a diagnostic device to detect and sort abnormal cells. Future applications in the study of the normal differentiation of cells from stem cells to mature cells are envisioned.

Acoustic emission study of deformation behavior of nacre

NASA Astrophysics Data System (ADS)

Luo, Shunfei; Luo, Hongyun; Han, Zhiyuan

2016-02-01

A study on the acoustic emission (AE) characteristics during deformation of nacre material was performed. We found that intermittent AE events are generated during nacre deformation. These avalanches may be attributed to microfracture events of the aragonite (CaCO3) nano-asperities and bridges during tablet sliding. These events show several critical features, such as the power-law distributions of the avalanche sizes and interval. These results suggest that the underlying fracture dynamics during nacre deformation display a self-organized criticality (SOC). The results also imply that the disorder and long-range correlation between local microfracture events may play important roles in nacre deformation.

Block versus continuum deformation in the Western United States

USGS Publications Warehouse

King, G.; Oppenheimer, D.; Amelung, F.

1994-01-01

The relative role of block versus continuum deformation of continental lithosphere is a current subject of debate. Continuous deformation is suggested by distributed seismicity at continental plate margins and by cumulative seismic moment sums which yield slip estimates that are less than estimates from plate motion studies. In contrast, block models are favored by geologic studies of displacement in places like Asia. A problem in this debate is a lack of data from which unequivocal conclusions may be reached. In this paper we apply the techniques of study used in regions such as the Alpine-Himalayan belt to an area with a wealth of instrumental data-the Western United States. By comparing plate rates to seismic moment release rates and assuming a typical seismogenic layer thickness of 15 km it appears that since 1850 about 60% of the Pacific-North America motion across the plate boundary in California and Nevada has occurred seismically and 40% aseismically. The San Francisco Bay area shows similar partitioning between seismic and aseismic deformation, and it can be shown that within the seismogenic depth range aseismic deformation is concentrated near the surface and at depth. In some cases this deformation can be located on creeping surface faults, but elsewhere it is spread over a several kilometer wide zone adjacent to the fault. These superficial creeping deformation zones may be responsible for the palaeomagnetic rotations that have been ascribed elsewhere to the surface expression of continuum deformation in the lithosphere. Our results support the dominant role of non-continuum deformation processes with the implication that deformation localization by strain softening must occur in the lower crust and probably the upper mantle. Our conclusions apply only to the regions where the data are good, and even within the Western United States (i.e., the Basin and Range) deformation styles remain poorly resolved. Nonetheless, we maintain that block motion is the

Dynamic soft tissue deformation estimation based on energy analysis

NASA Astrophysics Data System (ADS)

Gao, Dedong; Lei, Yong; Yao, Bin

2016-10-01

The needle placement accuracy of millimeters is required in many needle-based surgeries. The tissue deformation, especially that occurring on the surface of organ tissue, affects the needle-targeting accuracy of both manual and robotic needle insertions. It is necessary to understand the mechanism of tissue deformation during needle insertion into soft tissue. In this paper, soft tissue surface deformation is investigated on the basis of continuum mechanics, where a geometry model is presented to quantitatively approximate the volume of tissue deformation. The energy-based method is presented to the dynamic process of needle insertion into soft tissue based on continuum mechanics, and the volume of the cone is exploited to quantitatively approximate the deformation on the surface of soft tissue. The external work is converted into potential, kinetic, dissipated, and strain energies during the dynamic rigid needle-tissue interactive process. The needle insertion experimental setup, consisting of a linear actuator, force sensor, needle, tissue container, and a light, is constructed while an image-based method for measuring the depth and radius of the soft tissue surface deformations is introduced to obtain the experimental data. The relationship between the changed volume of tissue deformation and the insertion parameters is created based on the law of conservation of energy, with the volume of tissue deformation having been obtained using image-based measurements. The experiments are performed on phantom specimens, and an energy-based analytical fitted model is presented to estimate the volume of tissue deformation. The experimental results show that the energy-based analytical fitted model can predict the volume of soft tissue deformation, and the root mean squared errors of the fitting model and experimental data are 0.61 and 0.25 at the velocities 2.50 mm/s and 5.00 mm/s. The estimating parameters of the soft tissue surface deformations are proven to be useful

Monitoring of Deformation in Ground Before and After Tunnel Excavation

NASA Astrophysics Data System (ADS)

Eren, Mehmet; Hilmi Erkoç, Muharrem

2017-04-01

As population increase in metropolitan city, we need transportation and transmission tunnel. In this context, the engineers and administors attach impotance to building and planning underground-tunnel. Moreover, we must at regular intervals monitoring to deformation in underground-tunnel for quality and safety. Firstly, a deformation monitoring network is designed as perpendicular to the tunnel main axis. Secondly, the prescribed number of deformation measurements must be made. Finally, the deformation analysis is evaluated and its results is interpreted. This study investigates how deformation in monitoring network during and after tunnel excavate change.For this purpose, a deformation monitoring network of 18 object point and 4 reference point was established. Object points networks was designed steeply to the tunnel main axis as 3 cross section. Each cross section consisted of 3 point left, 2 point right and 1 point at the flowing line. Initial conditional measurement was made before tunnel excavation. Then the deformation measurement was made 5 period (1 period measured after tunnel excavate). All data sets were adjusted according to free adjustment method. The results from the investigation considering the tunnel line, a symmetrical subsidence was observed. The following day of tunnel excavation, we were observed %68 per of the total deformation. At the end of the last period measurements, %99 per of the total deformation was detected. Keywords: Tunnel, Deformation, Subsidence, Excavation

Numerical Investigations on Aerodynamic Forces of Deformable Foils in Hovering Motions

NASA Astrophysics Data System (ADS)

Zhao, Yong; Yin, Zhen; Su, Xiaohui; Zhang, Jiantao; Cao, Yuanwei

2017-09-01

The aerodynamic effects of wing deformation for hover flight are numerically investigated by a two-dimensional finite-volume (FV) Arbitrary Langrangian Eulerian (ALE) Navier-Stokes solver. Two deformation models are employed to study these effects in this paper, which are a full deformation model and a partial deformation one. Attentions are paid to the generation and development of leading edge vortex (LEV) and trailing edge vortex (TEV) which may illustrate the differences of lift force generation mechanisms from those of rigid wings. Moreover, lift coefficient Cl, drag coefficient Cd, and figure of merit, as well as energy consumption in hovering motion for different deformation foil models, are also studied. The results show that the deformed amplitude, 0.1*chord, among the cases simulated is an optimized camber amplitude for full deformation. The results obtained from the partial deformation foil model show that both Cl and Cd decrease with the increase of camber amplitude. It is found that the effect of deformation in the partial deformation model does not enhance lift force due to unfavorable camber. But TEV is significantly changed by the local AOA due to the deformation of the foil. Introduction.

Cenozoic Spatio-temporal Variations of Tian Shan Deformation

NASA Astrophysics Data System (ADS)

Sobel, E. R.; Bande, A.; Chen, J.; Thiede, R. C.; Macaulay, E. A.; Mikolaichuk, A.; Gilder, S. A.; Kley, J.

2016-12-01

The Cenozoic deformation of the Tian Shan is driven by north-vergent compression caused by the India-Asia collision, the indentation of the Pamir, and/or right-lateral transpression driven by the indentation of Arabia into Eurasia. The Talas-Fergana fault (TFF) region corresponds to the widest portion of high topography of the Tianshan Mountains. The width of the range tapers both east and west, albeit the geometry is more complex to the west. We synthesize published AFT, apatite (U-Th)/He, magnetostratigraphic and paleomagnetically-determined rotation data combined with our own work from the Tianshan domain to map spatial patterns of exhumation and deformation. Prior to middle Cenozoic deformation, the area of the present range was characterized by low relief; adjacent sedimentary basins record very low accumulation rates or hiatuses. Localized Eocene deformation events have been proposed but do not appear to reflect significant shortening. The first large pulse of deformation commenced in the Late Oligocene or Early Miocene, represented by isolated range uplifts, often related to reactivation of older structures, and pulses of clastic sedimentation. Perhaps the most significant deformation at this time occurred north of the Pamir along the NW-SE trending dextral TFF, in the Chatkal ranges at its NW end, and the Kokshaal and At-Bashi ranges at the SE end of the fault. The Fergana basin, west of the TFF, underwent significant counter-clockwise rotation that was accommodated by these structures. Relatively rapid slip along the TFF persisted from ca. 25 Ma until at least 13.5 Ma. A second, larger deformation episode commenced in the Middle-Late Miocene along the length of the Tian Shan. Similar-aged deformation is reported from the Tadjik depression and within the Pamir. Important questions to address include whether the drivers for the two episodes were the same and what were the relative roles of the Tarim block and the Pamir indenter in producing the deformation.

Dysfonctionnements radio-induits du transport colique chez le rat

NASA Astrophysics Data System (ADS)

François, A.; Lebrun, F.; Ksas, B.; Aigueperse, J.; Gourmelon, P.; MacNaughton, W. K.; Griffiths, N. M.

1998-04-01

The symptom commonly associated with whole body irradiation is diarrhoea, a still quite obscure phenomenon, which leads to decreased chance of cure of irradiated people. The aim of this study was to provide evidence for dysfunction of intestinal water and electrolyte transport regulation by the enteric nervous system after exposure to ionising radiation. This study shows decreased capacity of enteric nervous system to influence colonic transport 3days after irradiation, correlated to a diminished response to a neurotransmitter: serotonin. Radio-induced diarrhea may result from epithelial structural injury but also from impaired regulatory processes of intestinal transport. L'un des symptômes majeurs d'une irradiation corporelle totale ou abdominale est l'apparition de diarrhées, dont les causes sont encore mal connues, et qui mettent en jeu le pronostique vital de l'individu irradié. Cette étude vise à mettre en évidence l'atteinte de la régulation du transport intestinal d'eau et d'électrolytes par les rayonnements ionisants. On observe une diminution de la capacité du système nerveux entérique à influencer le transport colique 3jours après irradiation, corrélée à une diminution de la réponse épithéliale à un neurotransmetteur : la sérotonine. Les diarrhées radio-induites résulteraient d'une atteinte structurelle de l'épithélium mais également des processus de régulation du transport intestinal.

Kyste épidermoïde du quatrième ventricule: à propos d’un cas

PubMed Central

El Saqui, Abderrazzak; Aggouri, Mohamed; Benzagmout, Mohamed; Chakour, Khalid; Chaoui, Mohamed El Faiz

2017-01-01

Les kystes épidermoïdes sont des tumeurs bénignes rares développées à partir d'inclusions ectodermiques. Ils siègent habituellement au niveau de l'angle ponto-cérébelleux, la région para-sellaire et la fosse temporale. Leur siège au niveau du quatrième ventricule est exceptionnel. Nous rapportons le cas d'une patiente de 47 ans admise pour un syndrome d'hypertension intracrânienne associé à des troubles de la marche. Le diagnostic de kyste épidermoïde du V4 fut évoqué sur les données de l'IRM en séquences de diffusion puis confirmé en per opératoire et en histologie. L'exérèse chirurgicale a été subtotale en raison d'une adhérence de la capsule à la partie supérieure du plancher du V4. Après un recul de 36 mois, la patiente ne manifeste aucun signe de ré-évolution tumorale. PMID:28690753

Non-commutative geometry of the h-deformed quantum plane

NASA Astrophysics Data System (ADS)

Cho, S.; Madore, J.; Park, K. S.

1998-03-01

The h-deformed quantum plane is a counterpart of the q-deformed one in the set of quantum planes which are covariant under those quantum deformations of GL(2) which admit a central determinant. We have investigated the non-commutative geometry of the h-deformed quantum plane. There is a two-parameter family of torsion-free linear connections, a one-parameter sub-family of which are compatible with a skew-symmetric non-degenerate bilinear map. The skew-symmetric map resembles a symplectic 2-form and induces a metric. It is also shown that the extended h-deformed quantum plane is a non-commutative version of the Poincaré half-plane, a surface of constant negative Gaussian

Diagnostic et prise en charge du psoriasis

PubMed Central

Kim, Whan B.; Jerome, Dana; Yeung, Jensen

2017-01-01

Résumé Objectif Présenter aux cliniciens en soins primaires un aperçu pratique et à jour du diagnostic et de la prise en charge du psoriasis. Sources des données Une recension a été effectuée dans les bases de données de PubMed, MEDLINE, EMBASE et Cochrane pour trouver des méta-analyses, des études randomisées contrôlées, des revues systématiques et des études observationnelles pertinentes portant sur le diagnostic et la prise en charge du psoriasis. Message principal Le psoriasis est une maladie inflammatoire chronique et multisystémique qui affecte principalement la peau et les articulations. En plus des dimensions physiques de la maladie, le psoriasis a des répercussions émotionnelles et psychosociales considérables sur les patients, et nuit au fonctionnement social et aux relations interpersonnelles. En tant que maladie inflammatoire systémique, le psoriasis est associé à de multiples comorbidités, dont les maladies cardiovasculaires et les cancers. Le diagnostic est principalement d’ordre clinique et une biopsie de la peau est rarement nécessaire. Selon la sévérité de la maladie, un traitement approprié peut être amorcé. Pour les cas de légers à modérés, le traitement de première intention comporte des thérapies topiques, dont les corticostéroïdes, les analogues de la vitamine D3 et des produits combinés. Ces traitements topiques sont efficaces et peuvent être initiés et prescrits en toute sécurité par des médecins de soins primaires. Les patients dont les symptômes sont plus graves et réfractaires pourraient devoir être envoyés en consultation auprès d’un dermatologue pour une évaluation plus approfondie et une thérapie systémique. Conclusion De nombreux patients atteints de psoriasis consultent leur médecin de soins primaires pour une évaluation initiale et pour recevoir un traitement. La reconnaissance du psoriasis, de même que des comorbidités médicales et psychiatriques qui lui sont associ

Évolution nycthémérale des composantes biochimiques du phytoplancton de la retenue du barrage Idriss premier (Fès, Maroc)

NASA Astrophysics Data System (ADS)

Bahhou, J.; Alaoui Mhamdi, M.

1999-03-01

The diel changes of the biochemical composition of the phytoplankton were studied in the Idriss first reservoir (located on the Inaouen river at thirty Km from the city of Fes, Morrocco) during September 1994. Several biomass and metabolic indicators (proteins, carbohydrates, lipids, chlorophyll a and primary production) were assessed every fourth hour over tow days (7, 8 and 9 September). Since the Protein/Carbohydrates ratio (P/C) is largely recognised as a good integrator of the metabolic functions of the cells, we examined its distribution pattern concomitantly with aforementioned parameters. The results demonstrated enhanced P/C ratios clearly indicating that nutrients were sufficiently available for growth. In addition, this index showed a diel significant variation with levels higher in the night than in the day. Moreover, these results suggest that phytoplankton species during the night used the day-synthesised carbohydrates to insure the cell metabolic functioning. The P/C presents relatively high values in proposition to the ones that have been recorded in temperate regions, and seems to be related to azotic inputs of the Inaouen river. Dans le but de parfaire nos connaissances sur le fonctionnement du sous écosystème phytoplancton, nous nous sommes intéressés à étudier son cycle nycthéméral et son métabolisme cellulaire dans la retenue du barrage Idriss premier. Cette dernière, construite sur l'Oued Inaouène, est située à une trentaine de Km de la ville de Fès. Au cours de ce cycle, les prélèvements ont été effectués selon une séquence temporelle de 4 heures pendant 48 heures, les 7, 8 et 9 septembre 1994. L'étude de l'évolution des composantes biochimiques des cellules phytoplanctoniques à savoir les protéines, les glucides et les lipides a permis de mettre en évidence des variations nycthémérales importantes. Ces variations sont d'autant plus importantes que les variations spatiales observées entre les profondeurs. De plus

Inter and intra-modal deformable registration: continuous deformations meet efficient optimal linear programming.

PubMed

Glocker, Ben; Paragios, Nikos; Komodakis, Nikos; Tziritas, Georgios; Navab, Nassir

2007-01-01

In this paper we propose a novel non-rigid volume registration based on discrete labeling and linear programming. The proposed framework reformulates registration as a minimal path extraction in a weighted graph. The space of solutions is represented using a set of a labels which are assigned to predefined displacements. The graph topology corresponds to a superimposed regular grid onto the volume. Links between neighborhood control points introduce smoothness, while links between the graph nodes and the labels (end-nodes) measure the cost induced to the objective function through the selection of a particular deformation for a given control point once projected to the entire volume domain, Higher order polynomials are used to express the volume deformation from the ones of the control points. Efficient linear programming that can guarantee the optimal solution up to (a user-defined) bound is considered to recover the optimal registration parameters. Therefore, the method is gradient free, can encode various similarity metrics (simple changes on the graph construction), can guarantee a globally sub-optimal solution and is computational tractable. Experimental validation using simulated data with known deformation, as well as manually segmented data demonstrate the extreme potentials of our approach.

Deformation mechanisms and resealing of damage zones in experimentally deformed cemented and un-cemented clay-rich geomaterials, at low bulk strain

NASA Astrophysics Data System (ADS)

Desbois, Guillaume; Urai, Janos L.; Schuck, Bernhardt; Hoehne, Nadine; Oelker, Anne; Bésuelle, Pierre; Viggiani, Gioacchino; Schmatz, Joyce; Klaver, Jop

2017-04-01

A microphysics-based understanding of mechanical and fluid flow properties in clay-rich geomaterials is required for extrapolating better constitutive equations beyond the laboratory's time scales, so that predictions over the long term can be made less uncertain. In this contribution, we present microstructural investigations of rocks specimens sheared in triaxial compression at low bulk strain, by using the combination of broad-ion-beam (BIB) milling and scanning electron microscopy (SEM) to infer deformation mechanisms based on microstructures imaged at sub-micron resolution. Two end-member clay-rich geomaterials from European Underground Laboratories (URL) were analysed: (i) the poorly cemented Boom Clay sediment (BC from URL at Mol/Dessel, Belgium; confining pressure [CP] = 0.375 & 1.5 MPa) and (ii) the Callovo-Oxfordian claystone (COx from the URL at Bure, France; CP = 2 & 10 MPa). Although as a first approximation the inelastic bahvior of cemented and uncemented clay-rich geomaterials can be described by similar pressure-dependent hardening plasticity models, deformed samples in this contribution show very contrasting micro-scale behaviour: microstructures reveal brittle-ductile transitional behaviour in BC, whereas deformation in COx is dominantly cataclastic. In Boom Clay, at meso-scale, shear bands exhibit characteristics that are typical of uncemented small-grained clay-rich materials deformed at high shear strains, consisting of anastomosing shears interpreted as Y- and B-shears, which bound the passively deformed microlithons. At micro- down to nano-scale, the strong shape preferential orientation of clay aggregates in the anastomosing shears is interpreted to be responsible of the shear weakness. More over, the reworking of clay aggregates during deformation contributes to the collapsing of porosity in the shear band. Ductile deformation mechanisms represented by grain-rotation, grain-sliding, bending and granular flow mechanisms are strongly involved

Investigation of Deformation Dynamics in a Wrought Magnesium Alloy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wu, Wei; Qiao, Hua; An, Ke

2014-11-01

In the present research, the deformation dynamics and the effect of the deformation history on plastic deformation in a wrought magnesium alloy have been studied using real-time in-situ neutron diffraction measurements under a continuous loading condition and elastic-viscoplastic self-consistent (EVPSC) polycrystal modeling. The experimental results reveal that the pre-deformation delayed the activation of the tensile twinning during subsequent compression, mainly resulting from the residual strain. No apparent detwinning occurred during unloading and even in the elastic region during reverse loading. It is believed that the grain rotation played an important role in the elastic region during reverse loading. The EVPSCmore » model, which has been recently updated by implementing the twinning and detwinning model, was employed to characterize the deformation mechanism during the strain-path changes. The simulation result predicts well the experimental observation from the real-time in-situ neutron diffraction measurements. The present study provides a deep insight of the nature of deformation mechanisms in a hexagonal close-packed structured polycrystalline wrought magnesium alloy, which might lead to a new era of deformation-mechanism research.« less

Timescale dependent deformation of orogenic belts?

NASA Astrophysics Data System (ADS)

Hoth, S.; Friedrich, A. M.; Vietor, T.; Hoffmann-Rothe, A.; Kukowski, N.; Oncken, O.

2004-12-01

The principle aim to link geodetic, paleoseismologic and geologic estimates of fault slip is to extrapolate the respective rates from one timescale to the other to finally predict the recurrence interval of large earthquakes, which threat human habitats. This approach however, is based on two often implicitly made assumptions: a uniform slip distribution through time and space and no changes of the boundary conditions during the time interval of interest. Both assumptions are often hard to verify. A recent study, which analysed an exceptionally complete record of seismic slip for the Wasatch and related faults (Basin and Range province), ranging from 10 yr to 10 Myr suggests that such a link between geodetic and geologic rates might not exist, i.e., that our records of fault displacement may depend on the timescale over which they were measured. This view derives support from results of scaled 2D sandbox experiments, as well as numerical simulations with distinct elements, both of which investigated the effect of boundary conditions such as flexure, mechanic stratigraphy and erosion on the spatio-temporal distribution of deformation within bivergent wedges. We identified three types of processes based on their distinct spatio-temporal distribution of deformation. First, incremental strain and local strain rates are very short-lived are broadly distributed within the bivergent wedge and no temporal pattern could be established. Second, footwall shortcuts and the re-activation of either internal thrusts or of the retro shear-zone are irregularly distributed in time and are thus not predictable either, but last for a longer time interval. Third, the stepwise initiation and propagation of the deformation front is very regular in time, since it depends on the thickness of the incoming layer and on its internal and basal material properties. We consider the propagation of the deformation front as an internal clock of a thrust belt, which is therefore predictable. A

Deformation processes within wheel-rail adhesion in contact area

NASA Astrophysics Data System (ADS)

Albagachiev, A. Yu; Keropyan, A. M.

2018-03-01

The study of working surface deformation during interaction of open-pit locomotive tires allowed defining outstanding features of phenomena occurring in the contact area of interacting surfaces. It was found that processes typical for plastic saturated contact occur in the area of wheel-rail interaction of industrial railway transport. In case of plastic deformation exposed to heavy loads typical for open-pit locomotives, upon all rough surfaces of the contour contact area being fully deformed, the frame on which they are found is exposed to plastic deformation. Plastic deformation of roughness within the contact area of interacting surfaces leads to the increase in the actual area of their contact and, therefore, increases the towing capacity of mining machines. Finally, the available data on deformation characteristics with regard to processes occurring in the contact area of wheel-rail interaction will allow making theoretical forecasts on the expected design value of friction coefficient and, therefore, the towing capacity of open-pit locomotives.

Effectiveness of Ear Splint Therapy for Ear Deformities

PubMed Central

2017-01-01

Objective To present our experience with ear splint therapy for babies with ear deformities, and thereby demonstrate that this therapy is an effective and safe intervention without significant complications. Methods This was a retrospective study of 54 babies (35 boys and 19 girls; 80 ears; age ≤3 months) with ear deformities who had received ear splint therapy at the Center for Torticollis, Department of Physical Medicine and Rehabilitation, Ajou University Hospital between December 2014 and February 2016. Before the initiation of ear splint therapy, ear deformities were classified with reference to the standard terminology. We compared the severity of ear deformity before and after ear splint therapy by using the physician's ratings. We also compared the physician's ratings and the caregiver's ratings on completion of ear splint therapy. Results Among these 54 babies, 41 children (58 ears, 72.5%) completed the ear splint therapy. The mean age at initiation of therapy was 52.91±18.26 days and the treatment duration was 44.27±32.06 days. Satyr ear, forward-facing ear lobe, Darwinian notch, overfolded ear, and cupped ear were the five most common ear deformities. At the completion of therapy, the final physician's ratings of ear deformities were significantly improved compared to the initial ratings (8.28±1.44 vs. 2.51±0.92; p<0.001). There was no significant difference between the physician's ratings and the caregiver's ratings at the completion of ear splint therapy (8.28±1.44 vs. 8.0±1.61; p=0.297). Conclusion We demonstrated that ear splint therapy significantly improved ear deformities in babies, as measured by quantitative rating scales. Ear splint therapy is an effective and safe intervention for babies with ear deformities. PMID:28289646

Numerical modeling of the Indo-Australian intraplate deformation

NASA Astrophysics Data System (ADS)

Brandon, Vincent; Royer, Jean-Yves

2014-05-01

The Indo-Australian plate is perhaps the best example of wide intraplate deformation within an oceanic plate. The deformation is expressed by an unusual level of intraplate seismicity, including magnitude Mw > 8 events, large-scale folding and deep faulting of the oceanic lithosphere and reactivation of extinct fracture zones. The deformation pattern and kinematic data inversions suggest that the Indo-Australian plate can be viewed as a composite plate made of three rigid component plates - India, Capricorn, Australia - separated by wide and diffuse boundaries undergoing either extensional or compressional deformation. We tested this model using the SHELLS numerical code (Kong & Bird, 1995). The Indo-Australian plate is modeled by a mesh of 5281 spherical triangular finite elements. Mesh edges parallel the major extinct fracture zones so that they can be reactivated by reducing their friction rates. Strength of the plate is defined by the age of the lithosphere and seafloor topography. Model boundary conditions are only defined by the plate velocities predicted by the rotation vectors between rigid components of the Indo-Australian plate and their neighboring plates. Since the mesh limits all belong to rigid plates with fully defined Euler vectors, no conditions are imposed on the location, extent and limits of the diffuse and deforming zones. Using MORVEL plate velocities (DeMets et al., 2010), predicted deformation patterns are very consistent with that observed. Pre-existing structures of the lithosphere play an important role in the intraplate deformation and its distribution. The Chagos Bank focuses most of the extensional deformation between the Indian and Capricorn plates. Agreement between models and observation improves by weakening fossil fracture zones relative to the surrounding crust; however only limited sections of FZ's accommodate deformation. The reactivation of the Eocene FZ's in the Central Indian Basin (CIB) and Wharton Basin (WB) explains the

a Triangular Deformation of the Two-Dimensional POINCARÉ Algebra

NASA Astrophysics Data System (ADS)

Khorrami, M.; Shariati, A.; Abolhassani, M. R.; Aghamohammadi, A.

Contracting the h-deformation of SL(2, ℝ), we construct a new deformation of two-dimensional Poincaré's algebra, the algebra of functions on its group and its differential structure. It is seen that these dual Hopf algebras are isomorphic to each other. It is also shown that the Hopf algebra is triangular, and its universal R-matrix is also constructed explicitly. We then find a deformation map for the universal enveloping algebra, and at the end, give the deformed mass shells and Lorentz transformation.

HSR Model Deformation Measurements from Subsonic to Supersonic Speeds

NASA Technical Reports Server (NTRS)

Burner, A. W.; Erickson, G. E.; Goodman, W. L.; Fleming, G. A.

1999-01-01

This paper describes the video model deformation technique (VMD) used at five NASA facilities and the projection moire interferometry (PMI) technique used at two NASA facilities. Comparisons between the two techniques for model deformation measurements are provided. Facilities at NASA-Ames and NASA-Langley where deformation measurements have been made are presented. Examples of HSR model deformation measurements from the Langley Unitary Wind Tunnel, Langley 16-foot Transonic Wind Tunnel, and the Ames 12-foot Pressure Tunnel are presented. A study to improve and develop new targeting schemes at the National Transonic Facility is also described. The consideration of milled targets for future HSR models is recommended when deformation measurements are expected to be required. Finally, future development work for VMD and PMI is addressed.

All Madelung deformities are not endocrine

PubMed Central

Kumar, Ajay; Rai, Gopal K.; Akhtar, Javed; Phillip, Rajeev; Gutch, Manish; Arya, T. V. S.

2013-01-01

Madelung deformity is a rare inherited disorder associated with endocrine disorders like Turner's syndrome, pseudohypoparathyroidism, but can be seen with short stature homeobox deficiency conditions such as Leri-Weill dyschondrosteosis (LWD) and Langers mesomelic dysplasia. It has also been reported following trauma to the distal radius epiphysis neoplasia mucopolysaccharidosis (MPS) and achondroplasia. Madelung deformity is an abnormality of distal radial epiphysis where in progressive ulnar and volar tilt of the articular surface occurring in association with distal subluxation of ulna. A 13-year-old girl was referred to us for evaluation of bilateral deformity of wrist and short stature. There was ulnar deviation and dorsal tilt of bilateral hands without history of pain to the joint trauma and family history of similar illness. On X-ray, wrist showed malformed distal radial epiphysis with dorsal and ulnar shift and with increased length of phalanges suggestive of Madelung deformity. X-ray spine was normal. Ultrasound abdomen showed normal uterus and ovary and her follicle stimulating hormone. Luteinizing hormone was normal and so was urine MPS screening. Based on the above points the diagnosis of LWD was made. PMID:24251169

All Madelung deformities are not endocrine.

PubMed

Kumar, Ajay; Rai, Gopal K; Akhtar, Javed; Phillip, Rajeev; Gutch, Manish; Arya, T V S

2013-10-01

Madelung deformity is a rare inherited disorder associated with endocrine disorders like Turner's syndrome, pseudohypoparathyroidism, but can be seen with short stature homeobox deficiency conditions such as Leri-Weill dyschondrosteosis (LWD) and Langers mesomelic dysplasia. It has also been reported following trauma to the distal radius epiphysis neoplasia mucopolysaccharidosis (MPS) and achondroplasia. Madelung deformity is an abnormality of distal radial epiphysis where in progressive ulnar and volar tilt of the articular surface occurring in association with distal subluxation of ulna. A 13-year-old girl was referred to us for evaluation of bilateral deformity of wrist and short stature. There was ulnar deviation and dorsal tilt of bilateral hands without history of pain to the joint trauma and family history of similar illness. On X-ray, wrist showed malformed distal radial epiphysis with dorsal and ulnar shift and with increased length of phalanges suggestive of Madelung deformity. X-ray spine was normal. Ultrasound abdomen showed normal uterus and ovary and her follicle stimulating hormone. Luteinizing hormone was normal and so was urine MPS screening. Based on the above points the diagnosis of LWD was made.

Viscoelastic deformation of lipid bilayer vesicles.

PubMed

Wu, Shao-Hua; Sankhagowit, Shalene; Biswas, Roshni; Wu, Shuyang; Povinelli, Michelle L; Malmstadt, Noah

2015-10-07

Lipid bilayers form the boundaries of the cell and its organelles. Many physiological processes, such as cell movement and division, involve bending and folding of the bilayer at high curvatures. Currently, bending of the bilayer is treated as an elastic deformation, such that its stress-strain response is independent of the rate at which bending strain is applied. We present here the first direct measurement of viscoelastic response in a lipid bilayer vesicle. We used a dual-beam optical trap (DBOT) to stretch 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC) giant unilamellar vesicles (GUVs). Upon application of a step optical force, the vesicle membrane deforms in two regimes: a fast, instantaneous area increase, followed by a much slower stretching to an eventual plateau deformation. From measurements of dozens of GUVs, the average time constant of the slower stretching response was 0.225 ± 0.033 s (standard deviation, SD). Increasing the fluid viscosity did not affect the observed time constant. We performed a set of experiments to rule out heating by laser absorption as a cause of the transient behavior. Thus, we demonstrate here that the bending deformation of lipid bilayer membranes should be treated as viscoelastic.

Pneumatic tyres interacting with deformable terrains

NASA Astrophysics Data System (ADS)

Bekakos, C. A.; Papazafeiropoulos, G.; O'Boy, D. J.; Prins, J.

2016-09-01

In this study, a numerical model of a deformable tyre interacting with a deformable road has been developed with the use of the finite element code ABAQUS (v. 6.13). Two tyre models with different widths, not necessarily identical to any real industry tyres, have been created purely for research use. The behaviour of these tyres under various vertical loads and different inflation pressures is studied, initially in contact with a rigid surface and then with a deformable terrain. After ensuring that the tyre model gives realistic results in terms of the interaction with a rigid surface, the rolling process of the tyre on a deformable road was studied. The effects of friction coefficient, inflation pressure, rebar orientation and vertical load on the overall performance are reported. Regarding the modelling procedure, a sequence of models were analysed, using the coupling implicit - explicit method. The numerical results reveal that not only there is significant dependence of the final tyre response on the various initial driving parameters, but also special conditions emerge, where the desired response of the tyre results from specific optimum combination of these parameters.

Seismic Attenuation Structure and Intraplate Deformation

NASA Astrophysics Data System (ADS)

Bezada, M.; Kowalke, S.; Smale, J.

2017-12-01

It has been suggested that intraplate deformation and seismicity is localized at weak zones in the lithosphere and at rheological boundaries. Comparisons of intraplate deformation regions with mantle seismic velocity structure suggest a correlation, but are not universally accepted as compelling evidence. We present P-wave attenuation models built from records of teleseismic deep-focus earthquakes in three different regions that show significant correlation between attenuation structure and intraplate seismicity and deformation. In the eastern United States, the New Madrid, Wabash Valley, Eastern Tennessee, Central Virginia, and Carolina seismic zones all occur at or near the edges of high-Q (low attenuation) regions. In Spain, intraplate seismicity is absent from high-Q regions but relatively abundant in surrounding low-Q regions where intraplate orogeny is also observed. In Australia, where our model resolution is relatively poor owing to sparse and uneven station coverage, the Petermann and Alice Springs intraplate orogens occur near the edge of a high-Q feature roughly coinciding with the undeformed Amadeus basin. Our results suggest that lithospheric structure exerts important controls on the localization of intraplate deformation and seismicity and that seismic attenuation is a useful proxy for lithospheric strength.

SU-E-T-237: Deformable Image Registration and Deformed Dose Composite for Volumetric Evaluation of Multimodal Gynecological Cancer Treatments

DOE Office of Scientific and Technical Information (OSTI.GOV)

Albani, D; Sherertz, T; Ellis, R

2015-06-15

Purpose: Radiotherapy plans for patients with cervical cancer treated with EBRT followed by HDR brachytherapy are optimized by constraining dose to organs at risk (OARs). Risk of treatment related toxicities is estimated based on the dose received to the hottest 2cc (D2cc) of the bladder, bowel, rectum, and sigmoid. To account for intrafractional variation in OAR volume and positioning, a dose deformation method is proposed for more accurate evaluation of dose distribution for these patients. Methods: Radiotherapy plans from five patients who received 50.4Gy pelvic EBRT followed by 30Gy in five fractions of HDR brachytherapy, using split-ring and tandem applicators,more » were retrospectively evaluated using MIM Software version 6.0. Dose accumulation workflows were used for initial deformation of EBRT and HDR planning CTs onto a common HDR planning CT. The Reg Refine tool was applied with user-specified local alignments to refine the deformation. Doses from the deformed images were transferred to the common planning CT. Deformed doses were scaled to the EQD2, following the linear-quadratic BED model (considered α/β ratio for tumor as 10, and 3 for rest of the tissues), and then combined to create the dose composite. MIM composite doses were compared to the clinically-reported plan assessments based upon the American Brachytherapy Society (ABS) guidelines for cervical HDR brachytherapy treatment. Results: Bladder D2cc exhibited significant reduction (−11.4%±3.85%, p< 0.02) when evaluated using MIM deformable dose composition. Differences observed for bowel, rectum, and sigmoid D2cc were not significant (−0.58±7.37%, −4.13%±13.7%, and 8.58%±4.71%, respectively and p>0.05 for all) relative to the calculated values used clinically. Conclusion: Application of deformable dose composite techniques may lead to more accurate total dose reporting and can allow for elevated dose to target structures with the assurance of not exceeding dose to OARs. Further

Particularités de la cardiomyopathie du péripartum en Afrique: le cas du Togo sur une étude prospective de 41 cas au Centre Hospitalier et Universitaire Sylvanus Olympio de Lomé

PubMed Central

Pio, Machihude; Afassinou, Yaovi; Baragou, Soodougoua; Akue, Edem Goeh; Péssinaba, Souleymane; Atta, Borgatia; Ehlan, Koffi; Alate, Amouzou; Damorou, Findibe

2014-01-01

Introduction La cardiomyopathie du péripartum (CMPP) est une défaillance cardiaque dont l’étiologie demeure encore méconnue. Méthodes Il s'agit d'une étude prospective descriptive réalisée dans le service de cardiologie du CHU Sylvanus olympio de Lomé du 1er janvier 2010 au 30 avril 2012. Elle a concerné 41 patientes ayant présenté une insuffisance cardiaque entre le 8eme mois de la grossesse et les 5 premiers mois du post-partum. Résultats L’âge moyen des patientes était de 31,47 ans (extrêmes 21 et 44ans). L'incidence de la CMPP était de 1/362 grossesses. La parité moyenne était de 3,07 (extrêmes 1 et 6). Les symptômes étaient apparus dans le post-partum dans 90,24% des cas. Un retard important de diagnostic était observé. L'insuffisance cardiaque globale était le mode de décompensation dans 65,85%. Les signes électrocardiographiques étaient essentiellement la tachycardie sinusale (97,56%) et l'hypertrophie ventriculaire gauche (97,56%). L’échographie cardiaque a montré dans tous les cas une cardiomyopathie dilatée. Quatre cas de thrombus intraventriculaire gauche étaient notés. La FEVG était sévèrement altérée. L'HTAP était importante dans 56,09%. Conclusion La cardiomyopathie du péripartum est une complication cardiaque grave de la grossesse de cause inconnue, fréquente dans la population africaine. PMID:25309645

Large-scale deformation associated with ridge subduction

USGS Publications Warehouse

Geist, E.L.; Fisher, M.A.; Scholl, D. W.

1993-01-01

Continuum models are used to investigate the large-scale deformation associated with the subduction of aseismic ridges. Formulated in the horizontal plane using thin viscous sheet theory, these models measure the horizontal transmission of stress through the arc lithosphere accompanying ridge subduction. Modelling was used to compare the Tonga arc and Louisville ridge collision with the New Hebrides arc and d'Entrecasteaux ridge collision, which have disparate arc-ridge intersection speeds but otherwise similar characteristics. Models of both systems indicate that diffuse deformation (low values of the effective stress-strain exponent n) are required to explain the observed deformation. -from Authors

Red blood cell dynamics: from cell deformation to ATP release.

PubMed

Wan, Jiandi; Forsyth, Alison M; Stone, Howard A

2011-10-01

The mechanisms of red blood cell (RBC) deformation under both static and dynamic, i.e., flow, conditions have been studied extensively since the mid 1960s. Deformation-induced biochemical reactions and possible signaling in RBCs, however, were proposed only fifteen years ago. Therefore, the fundamental relationship between RBC deformation and cellular signaling dynamics i.e., mechanotransduction, remains incompletely understood. Quantitative understanding of the mechanotransductive pathways in RBCs requires integrative studies of physical models of RBC deformation and cellular biochemical reactions. In this article we review the physical models of RBC deformation, spanning from continuum membrane mechanics to cellular skeleton dynamics under both static and flow conditions, and elaborate the mechanistic links involved in deformation-induced ATP release. This journal is © The Royal Society of Chemistry 2011

Mechanical biocompatibility of highly deformable biomedical materials.

PubMed

Mazza, Edoardo; Ehret, Alexander E

2015-08-01

Mismatch of mechanical properties between highly deformable biomedical materials and adjacent native tissue might lead to short and long term health impairment. The capability of implants to deform at the right level, i.e. similar to the macroscopic mechanical response of the surrounding biological materials, is often associated with dissimilar microstructural deformation mechanisms. This mismatch on smaller length scales might lead to micro-injuries, cell damage, inflammation, fibrosis or necrosis. Hence, the mechanical biocompatibility of soft implants depends not only on the properties and composition of the implant material, but also on its organization, distribution and motion at one or several length scales. The challenges related to the analysis and attainment of mechanical biocompatibility are illustrated with two examples: prosthetic meshes for hernia and pelvic repair and electrospun scaffolds for tissue engineering. For these material systems we describe existing methods for characterization and analysis of the non-linear response to uniaxial and multiaxial stress states, its time and history dependence, and the changes in deformation behavior associated with tissue in-growth and material resorption. We discuss the multi-scale deformation behavior of biomaterials and adjacent tissue, and indicate major interdisciplinary questions to be addressed in future research. Copyright © 2015 Elsevier Ltd. All rights reserved.

Comparative study on DuPont analysis and DEA models for measuring stock performance using financial ratio

NASA Astrophysics Data System (ADS)

Arsad, Roslah; Shaari, Siti Nabilah Mohd; Isa, Zaidi

2017-11-01

Determining stock performance using financial ratio is challenging for many investors and researchers. Financial ratio can indicate the strengths and weaknesses of a company's stock performance. There are five categories of financial ratios namely liquidity, efficiency, leverage, profitability and market ratios. It is important to interpret the ratio correctly for proper financial decision making. The purpose of this study is to compare the performance of listed companies in Bursa Malaysia using Data Envelopment Analysis (DEA) and DuPont analysis Models. The study is conducted in 2015 involving 116 consumer products companies listed in Bursa Malaysia. The estimation method of Data Envelopment Analysis computes the efficiency scores and ranks the companies accordingly. The Alirezaee and Afsharian's method of analysis based Charnes, Cooper and Rhodes (CCR) where Constant Return to Scale (CRS) is employed. The DuPont analysis is a traditional tool for measuring the operating performance of companies. In this study, DuPont analysis is used to evaluate three different aspects such as profitability, efficiency of assets utilization and financial leverage. Return on Equity (ROE) is also calculated in DuPont analysis. This study finds that both analysis models provide different rankings of the selected samples. Hypothesis testing based on Pearson's correlation, indicates that there is no correlation between rankings produced by DEA and DuPont analysis. The DEA ranking model proposed by Alirezaee and Asharian is unstable. The method cannot provide complete ranking because the values of Balance Index is equal and zero.

Deformation interplay at Hawaii Island

NASA Astrophysics Data System (ADS)

Shirzaei, M.; Walter, T. R.

2009-12-01

Volcanoes are known to be closely related to the tectonic environment, including vent locations and eruptions resulting from faults and earthquakes. Similarly, adjacent volcanoes interact with each other in time and space, as suggested for the Hawaiian volcanoes Kilauea and Mauna Loa. New satellite radar data imply even more complex deformation interplay in Hawaii than previously thought, involving magma chamber pressure changes, dike intrusions, slow earthquakes and ground subsidence. The affected regions are the Mauna Loa and Kilauea volcano summits, their active rift zones, the island’s unstable southeast flank and even the capital city of Hilo. Based on the data acquired by the European satellite ENVISAT, we present in this work a five-year spatio-temporal analysis of the deformation signals recorded between 2003 and 2008. The data suggests that most of the deformation sources are acting in chorus. The magma intrusion at the Mauna Loa chamber and the intrusion into the Kilauea rift dike are correlated in time while also interacting with gravity-driven flank movement events. Some of the events occur silently underneath the Kilauea south flank, such as slow earthquakes that may largely affect all of the active magmatic systems and reverse their sign of correlation. This study of the interplay between multiple deformations and inherently coupled systems provides a better understanding of Hawaiian volcano activity and may lead to new methods for assessing the hazards that arise during volcano-tectonic activities elsewhere.

Multiple deformation mechanisms operating at seismogenic depths: Tectonic pseudotachylyte and associated deformation from the central Sierra Nevada, California

NASA Astrophysics Data System (ADS)

Prante, M. R.; Evans, J. P.

2012-12-01

Description and identification of fault-related deformation products that are diagnostic of seismic slip have implications for the energy budget of earthquakes, fault strength, and fault-rock assemblages. We describe tectonic pseduotachylyte, cataclastic rocks, crystal-plastic deformation, and hydrothermal alteration form faults exhumed from seismogenic depths in the Volcanic Lakes area, in northern Sequoia and Kings Canyon National Park, CA, USA. Fault rock protoliths include Mesozoic granite and granodiorite plutonic and limited metasedimentary and metavolcanic rocks. These plutonic and metamorphic rocks are cross-cut by the E-W striking, steeply dipping, left-lateral strike-slip Granite Pass (GPF) and Glacier Lakes faults (GLF). Cross-cutting relationships and microstructural data suggest that the GPF is the oldest fault in the area and preserves evidence for coeval brittle and plastic crystal deformation, and hydrothermal fluid-flow. Tectonic pseudotachylyte from the area has been dated using the 40Ar/39Ar method at 76.6 ± 0.3 Ma; when placed into a thermochronologic framework for the plutonic host rock it can be inferred that the pseudotachylyte formed at depths between 2.4-6.0 km with ambient temperatures between 110-160°C. Exceptionally well preserved tectonic pseudotachylyte from the GLF and GPF contain evidence for a frictional melt origin including: 1) plagioclase spherulites and microlites, 2) injection vein morphology, 3) amygdules, 4) viscous flow banding and folds, and 5) embayed and corroded clasts. Pseudotachylyte from the GPF and GLF is associated with brittle and plastic deformation in the damage zone of the faults. Evidence for plastic deformation includes undulose extinction, deformation lamellae, subgrain development, and grain boundary bulging in quartz; and limited undulose extinction in feldspar. Additionally, abundant hydrothermal alteration and mineralization has been documented in the GPF and GLF fault zones, including, chlorite

Loading Deformation Characteristic Simulation Study of Engineering Vehicle Refurbished Tire

NASA Astrophysics Data System (ADS)

Qiang, Wang; Xiaojie, Qi; Zhao, Yang; Yunlong, Wang; Guotian, Wang; Degang, Lv

2018-05-01

The paper constructed engineering vehicle refurbished tire computer geometry model, mechanics model, contact model, finite element analysis model, did simulation study on load-deformation property of engineering vehicle refurbished tire by comparing with that of the new and the same type tire, got load-deformation of engineering vehicle refurbished tire under the working condition of static state and ground contact. The analysis result shows that change rules of radial-direction deformation and side-direction deformation of engineering vehicle refurbished tire are close to that of the new tire, radial-direction and side-direction deformation value is a little less than that of the new tire. When air inflation pressure was certain, radial-direction deformation linear rule of engineer vehicle refurbished tire would increase with load adding, however, side-direction deformation showed linear change rule, when air inflation pressure was low; and it would show increase of non-linear change rule, when air inflation pressure was very high.

Overview of deformable mirror technologies for adaptive optics and astronomy

NASA Astrophysics Data System (ADS)

Madec, P.-Y.

2012-07-01

From the ardent bucklers used during the Syracuse battle to set fire to Romans’ ships to more contemporary piezoelectric deformable mirrors widely used in astronomy, from very large voice coil deformable mirrors considered in future Extremely Large Telescopes to very small and compact ones embedded in Multi Object Adaptive Optics systems, this paper aims at giving an overview of Deformable Mirror technology for Adaptive Optics and Astronomy. First the main drivers for the design of Deformable Mirrors are recalled, not only related to atmospheric aberration compensation but also to environmental conditions or mechanical constraints. Then the different technologies available today for the manufacturing of Deformable Mirrors will be described, pros and cons analyzed. A review of the Companies and Institutes with capabilities in delivering Deformable Mirrors to astronomers will be presented, as well as lessons learned from the past 25 years of technological development and operation on sky. In conclusion, perspective will be tentatively drawn for what regards the future of Deformable Mirror technology for Astronomy.

Amniotic Constriction Bands: Secondary Deformities and Their Treatments.

PubMed

Drury, Benjamin T; Rayan, Ghazi M

2018-01-01

The purpose of this study was to report the surgical treatment experience of patients with amniotic constriction bands (ACB) over a 35-year interval and detail consequential limb deformities with emphasis on hands and upper extremities, along with the nature and frequency of their surgical treatment methods. Fifty-one patients were identified; 26 were males and 25 females. The total number of deformities was listed. The total number of operations, individual procedures, and operations plus procedures that were done for each patient and their frequency were recorded. The total number of operations was 117, and total number of procedures was 341. More procedures were performed on the upper extremity (85%) than the lower extremity (15%). Including the primary deformity ACB, 16 different hand deformities secondary to ACB were encountered. Sixteen different surgical methods for the upper extremity were utilized; a primary procedure for ACB and secondary reconstructions for all secondary deformities. Average age at the time of the first procedure was 9.3 months. The most common procedures performed, in order of frequency, were excision of ACB plus Z-plasty, release of partial syndactyly, release of fenestrated syndactyly, full-thickness skin grafts, resection of digital bony overgrowth from amputation stumps, and deepening of first and other digital web spaces. Many hand and upper extremity deformities secondary to ACB are encountered. Children with ACB may require more than one operation including multiple procedures. Numerous surgical methods of reconstruction for these children's secondary deformities are necessary in addition to the customary primary procedure of excision of ACB and Z-plasty.

Island of stability for consistent deformations of Einstein's gravity.

PubMed

Berkhahn, Felix; Dietrich, Dennis D; Hofmann, Stefan; Kühnel, Florian; Moyassari, Parvin

2012-03-30

We construct deformations of general relativity that are consistent and phenomenologically viable, since they respect, in particular, cosmological backgrounds. These deformations have unique symmetries in accordance with their Minkowski cousins (Fierz-Pauli theory for massive gravitons) and incorporate a background curvature induced self-stabilizing mechanism. Self-stabilization is essential in order to guarantee hyperbolic evolution in and unitarity of the covariantized theory, as well as the deformation's uniqueness. We show that the deformation's parameter space contains islands of absolute stability that are persistent through the entire cosmic evolution.

Analytical volcano deformation source models

USGS Publications Warehouse

Lisowski, Michael; Dzurisin, Daniel

2007-01-01

Primary volcanic landforms are created by the ascent and eruption of magma. The ascending magma displaces and interacts with surrounding rock and fluids as it creates new pathways, flows through cracks or conduits, vesiculates, and accumulates in underground reservoirs. The formation of new pathways and pressure changes within existing conduits and reservoirs stress and deform the surrounding rock. Eruption products load the crust. The pattern and rate of surface deformation around volcanoes reflect the tectonic and volcanic processes transmitted to the surface through the mechanical properties of the crust.

Study of Deformation Bands in Ignimbrites in Shihtiping, Eastern Taiwan

NASA Astrophysics Data System (ADS)

Lin, S. T.; Huang, W. J.

2014-12-01

Shihtiping is located at the coast of eastern Taiwan, where rocks are the products of subaerial eruption by Chimei Volcano in late Miocene. The major lithology is ignimbrite along with pyroclasts in various sizes. Deformation bands ubiquitously appear in such loose, high-porosity, rocks. This study aims at documenting the occurrence of the deformation bands, understanding their formation mechanism and discussing their tectonic implications. There are two sets of deformation bands with orientations of N60°~80°E and N50°~70°W, respectively, in Shihtiping. The dip angles of both range from 70° to 90°. Commonly, the deformation bands are exposed as single trace or braided trace composed of several individuals. They can be traced easily because they are protruding owning to more weathering-resistant than the host rock. Thickness and separation of single deformation band are in the order of millimeter and millimeter to centimeter, respectively. Thickness of zone of deformation band ranges from few mm to tens of cm and total separation is commonly tens of cm. Based on microscopic examination, mineral assemblages in deformation bands usually include plagioclase, hornblende and augite. Although mineral assemblages are the same as host rock, clasts in deformation bands are rounder and smaller. Thus, it results in closed packing and porosity reduction within deformation bands. Summed up the observations, the deformation bands in Shihtiping were formed by cataclasis and can be classified as cataclastic band. They may reflect the regional paelostress state but not accompanied with any tectonic fault.

Large poroelastic deformation of a soft material

NASA Astrophysics Data System (ADS)

MacMinn, Christopher W.; Dufresne, Eric R.; Wettlaufer, John S.

2014-11-01

Flow through a porous material will drive mechanical deformation when the fluid pressure becomes comparable to the stiffness of the solid skeleton. This has applications ranging from hydraulic fracture for recovery of shale gas, where fluid is injected at high pressure, to the mechanics of biological cells and tissues, where the solid skeleton is very soft. The traditional linear theory of poroelasticity captures this fluid-solid coupling by combining Darcy's law with linear elasticity. However, linear elasticity is only volume-conservative to first order in the strain, which can become problematic when damage, plasticity, or extreme softness lead to large deformations. Here, we compare the predictions of linear poroelasticity with those of a large-deformation framework in the context of two model problems. We show that errors in volume conservation are compounded and amplified by coupling with the fluid flow, and can become important even when the deformation is small. We also illustrate these results with a laboratory experiment.

PHOTOMETRIC ANALYSIS OF HS Aqr, EG Cep, VW LMi, AND DU Boo

DOE Office of Scientific and Technical Information (OSTI.GOV)

Djurasevic, G.; Latkovic, O.; Bastuerk, Oe.

2013-03-15

We analyze new multicolor light curves for four close late-type binaries: HS Aqr, EG Cep, VW LMi, and DU Boo, in order to determine the orbital and physical parameters of the systems and estimate the distances. The analysis is done using the modeling code of G. Djurasevic, and is based on up-to-date measurements of spectroscopic elements. All four systems have complex, asymmetric light curves that we model by including bright or dark spots on one or both components. Our findings indicate that HS Aqr and EG Cep are in semi-detached, while VW LMi and DU Boo are in overcontact configurations.

Differents aspects du fer dans l'organisme

PubMed Central

Bessis, Marcel; Breton-Gorius, Janine

1959-01-01

On voit des molécules de ferritine apparaitre dans le cytoplasme des cellules réticulaires au cours de la digestion des érythrocytes, autour des stromas phagocytés. Cette ferritine s'accumule en amas dans lesquels entrent d'autres substances, en particulier des lipides, provenant aussi des stromas globulaires et qui apparaissent sous forme myélinique. Souvent la ferritine se dispose d'une manière cristalline. Parfois la ferritine et l'apoferritine alternent dans ces cristaux. Parfois l'hémosidérine contient des cristaux qui semblent bien être de l'apoferritine pure. L'injection de sels de fer donne lieu à l'apparition de ferritine dans les cellules réticulaires. Dans les conditions de nos expériences, la plus grande partie du fer injecté était sous forme de ferritine dans un délai de 3 jours. Un aspect intermédiaire entre celui du fer injecté et celui de la ferritine a été trouvé. Dans le cas des injections de saccharate de fer ce sont de fines aiguilles; dans le cas des injections de lactate de fer, il s'agit de masses fibreuses. PMID:13800106

Finite Element Analysis of Plastic Deformation During Impression Creep

NASA Astrophysics Data System (ADS)

Naveena; Ganesh Kumar, J.; Mathew, M. D.

2015-04-01

Finite element (FE) analysis of plastic deformation associated with impression creep deformation of 316LN stainless steel was carried out. An axisymmetric FE model of 10 × 10 × 10 mm specimen with 1-mm-diameter rigid cylindrical flat punch was developed. FE simulation of impression creep deformation was performed by assuming elastic-plastic-power-law creep deformation behavior. Evolution of the stress with time under the punch during elastic, plastic, and creep processes was analyzed. The onset of plastic deformation was found to occur at a nominal stress about 1.12 times the yield stress of the material. The size of the developed plastic zone was predicted to be about three times the radius of the punch. The material flow behavior and the pile-up on specimen surface have been modeled.

Large Scale Deformation of the Western US Cordillera

NASA Technical Reports Server (NTRS)

Bennett, Richard A.

2001-01-01

Destructive earthquakes occur throughout the western US Cordillera (WUSC), not just within the San Andreas fault zone. But because we do not understand the present-day large-scale deformations of the crust throughout the WUSC, our ability to assess the potential for seismic hazards in this region remains severely limited. To address this problem, we are using a large collection of Global Positioning System (GPS) networks which spans the WUSC to precisely quantify present-day large-scale crustal deformations in a single uniform reference frame. Our work can roughly be divided into an analysis of the GPS observations to infer the deformation field across and within the entire plate boundary zone and an investigation of the implications of this deformation field regarding plate boundary dynamics.

Nonaxial hexadecapole deformation effects on the fission barrier

NASA Astrophysics Data System (ADS)

Kardan, A.; Nejati, S.

2016-06-01

Fission barrier of the heavy nucleus 250Cf is analyzed in a multi-dimensional deformation space. This space includes two quadrupole (ɛ2,γ) and three hexadecapole deformation (ɛ40,ɛ42,ɛ44) parameters. The analysis is performed within an unpaired macroscopic-microscopic approach. Special attention is given to the effects of the axial and non-axial hexadecapole deformation shapes. It is found that the inclusion of the nonaxial hexadecapole shapes does not change the fission barrier heights, so it should be sufficient to minimize the energy in only one degree of freedom in the hexadecapole space ɛ4. The role of hexadecapole deformation parameters is also discussed on the Lublin-Strasbourg drop (LSD) macroscopic and the Strutinsky shell energies.

Micromechanisms of deformation in shales

NASA Astrophysics Data System (ADS)

Bonnelye, A.; Gharbi, H.; Hallais, S.; Dimanov, A.; Bornert, M.; Picard, D.; Mezni, M.; Conil, N.

2017-12-01

One of the envisaged solutions for nuclear wastes disposal is underground repository in shales. For this purpose, the Callovo Oxfordian (Cox) argillaceous formation is extensively studied. The hydro-mechanical behavior of the argillaceous rock is complex, like the multiphase and multi-scale structured material itself. The argilaceous matrix is composed of interstratified illite-smectite particles, it contains detritic quartz and calcite, accessory pyrite, and the rock porosity ranges from micrometre to nanometre scales. Besides the bedding anisotropy, structural variabilities exist at all scales, from the decametric-metric scales of the geological formation to the respectively millimetric and micrometric scales of the aggregates of particles and clay particles Our study aims at understanding the complex mechanisms which are activated at the micro-scale and are involved in the macroscopic inelastic deformation of such a complex material. Two sets of experiments were performed, at two scales on three bedding orientations (90°, 45° and 0°). The first set was dedicated to uniaxial deformation followed with an optical set-up with a pixel resolution of 0.55µm. These experiments allowed us to see the fracture propagation with different patterns depending on the bedding orientation. For the second set of experiments, an experimental protocol was developed in order to perform uniaxial deformation experiment at controlled displacement rate, inside an environmental scanning electron microscope (ESEM), under controlled relative humidity, in order to preserve as much as possible the natural state of saturation of shales. We aimed at characterizing the mechanical anisotropy and the mechanisms involved in the deformation, with an image resolution below the micormeter. The observed sample surfaces were polished by broad ion beam in order to reveal the fine microstructures of the argillaceous matrix. In both cases, digital images were acquired at different loading stages during

Preliminary deformation model for National Seismic Hazard map of Indonesia

DOE Office of Scientific and Technical Information (OSTI.GOV)

Meilano, Irwan; Gunawan, Endra; Sarsito, Dina

Preliminary deformation model for the Indonesia’s National Seismic Hazard (NSH) map is constructed as the block rotation and strain accumulation function at the elastic half-space. Deformation due to rigid body motion is estimated by rotating six tectonic blocks in Indonesia. The interseismic deformation due to subduction is estimated by assuming coupling on subduction interface while deformation at active fault is calculated by assuming each of the fault‘s segment slips beneath a locking depth or in combination with creeping in a shallower part. This research shows that rigid body motion dominates the deformation pattern with magnitude more than 15 mm/year, except inmore » the narrow area near subduction zones and active faults where significant deformation reach to 25 mm/year.« less

Corneal biomechanical properties from air-puff corneal deformation imaging

NASA Astrophysics Data System (ADS)

Marcos, Susana; Kling, Sabine; Bekesi, Nandor; Dorronsoro, Carlos

2014-02-01

The combination of air-puff systems with real-time corneal imaging (i.e. Optical Coherence Tomography (OCT), or Scheimpflug) is a promising approach to assess the dynamic biomechanical properties of the corneal tissue in vivo. In this study we present an experimental system which, together with finite element modeling, allows measurements of corneal biomechanical properties from corneal deformation imaging, both ex vivo and in vivo. A spectral OCT instrument combined with an air puff from a non-contact tonometer in a non-collinear configuration was used to image the corneal deformation over full corneal cross-sections, as well as to obtain high speed measurements of the temporal deformation of the corneal apex. Quantitative analysis allows direct extraction of several deformation parameters, such as apex indentation across time, maximal indentation depth, temporal symmetry and peak distance at maximal deformation. The potential of the technique is demonstrated and compared to air-puff imaging with Scheimpflug. Measurements ex vivo were performed on 14 freshly enucleated porcine eyes and five human donor eyes. Measurements in vivo were performed on nine human eyes. Corneal deformation was studied as a function of Intraocular Pressure (IOP, 15-45 mmHg), dehydration, changes in corneal rigidity (produced by UV corneal cross-linking, CXL), and different boundary conditions (sclera, ocular muscles). Geometrical deformation parameters were used as input for inverse finite element simulation to retrieve the corneal dynamic elastic and viscoelastic parameters. Temporal and spatial deformation profiles were very sensitive to the IOP. CXL produced a significant reduction of the cornea indentation (1.41x), and a change in the temporal symmetry of the corneal deformation profile (1.65x), indicating a change in the viscoelastic properties with treatment. Combining air-puff with dynamic imaging and finite element modeling allows characterizing the corneal biomechanics in-vivo.

Evaluation of various deformable image registrations for point and volume variations

NASA Astrophysics Data System (ADS)

Han, Su Chul; Lee, Soon Sung; Kim, Mi-Sook; Ji, Young Hoon; Kim, Kum Bae; Choi, Sang Hyun; Park, Seungwoo; Jung, Haijo; Yoo, Hyung Jun; Yi, Chul Young

2015-07-01

The accuracy of deformable image registration (DIR) has a significant dosimetric impact in radiationtreatment planning. Many groups have studied the accuracy of DIR. In this study, we evaluatedthe accuracy of various DIR algorithms by using variations of the deformation point and volume.The reference image (I ref ) and volume (V ref ) were first generated by using virtual deformation QAsoftware (ImSimQA, Oncology System Limited, UK). We deformed I ref with axial movement of thedeformation point and V ref , depending on the type of deformation (relaxation and contraction) inImSimQA software. The deformed image (I def ) and volume (V def ) acquired by using the ImSimQAsoftware were inversely deformed relative to I ref and V ref by using DIR algorithms. As a result,we acquired a deformed image (I id ) from I def and volume (V id ) from V ref . Four intensity-basedalgorithms were tested by following the horn-schunk optical flow (HS), iterative optical flow (IOF),modified demons (MD) and fast demons (FD) with the Deformable Image Registration and AdaptiveRadiotherapy Toolkit (DIRART) of MATLAB. The image similarity between I ref and I id wascalculated to evaluate the accuracy of DIR algorithms using by Normalized Mutual Information(NMI) and Normalized Cross Correlation (NCC) metrics, when the distance of point deformationwas moved 4 mm, the value of NMI was above 1.81 and that of NCC was above 0.99 in all DIRalgorithms. As the degree of deformation was increased, the degree of image similarity decreased.When the V ref was increased or decreased by about 12%, the difference between V ref and V id waswithin ±5% regardless of the type of deformation, the deformation was classified into two types:deformation 1 increased the V ref (relaxation) and deformation 2 decreased the V ref (contraction).The value of the Dice Similarity Coefficient (DSC) was above 0.95 in deformation 1 except for theMD algorithm. In the case of deformation 2, the value of the DSC was above 0.95 in

Monitoring Bridge Dynamic Deformation in Vibration by Digital Photography

NASA Astrophysics Data System (ADS)

Yu, Chengxin; Zhang, Guojian; Liu, Xiaodong; Fan, Li; Hai, Hua

2018-01-01

This study adopts digital photography to monitor bridge dynamic deformation in vibration. Digital photography in this study is based on PST-TBPM (photographing scale transformation-time baseline parallax method). Firstly, we monitor the bridge in static as a zero image. Then, we continuously monitor the bridge in vibration as the successive images. Based on the reference points on each image, PST-TBPM is used to calculate the images to obtain the dynamic deformation values of these deformation points. Results show that the average measurement accuracies are 0.685 pixels (0.51mm) and 0.635 pixels (0.47mm) in X and Z direction, respectively. The maximal deformations in X and Z direction of the bridge are 4.53 pixels and 5.21 pixels, respectively. PST-TBPM is valid in solving the problem that the photographing direction is not perpendicular to the bridge. Digital photography in this study can be used to assess bridge health through monitoring the dynamic deformation of a bridge in vibration. The deformation trend curves also can warn the possible dangers over time.

A position-dependent mass harmonic oscillator and deformed space

NASA Astrophysics Data System (ADS)

da Costa, Bruno G.; Borges, Ernesto P.

2018-04-01

We consider canonically conjugated generalized space and linear momentum operators x^ q and p^ q in quantum mechanics, associated with a generalized translation operator which produces infinitesimal deformed displacements controlled by a deformation parameter q. A canonical transformation (x ^ ,p ^ ) →(x^ q,p^ q ) leads the Hamiltonian of a position-dependent mass particle in usual space to another Hamiltonian of a particle with constant mass in a conservative force field of the deformed space. The equation of motion for the classical phase space (x, p) may be expressed in terms of the deformed (dual) q-derivative. We revisit the problem of a q-deformed oscillator in both classical and quantum formalisms. Particularly, this canonical transformation leads a particle with position-dependent mass in a harmonic potential to a particle with constant mass in a Morse potential. The trajectories in phase spaces (x, p) and (xq, pq) are analyzed for different values of the deformation parameter. Finally, we compare the results of the problem in classical and quantum formalisms through the principle of correspondence and the WKB approximation.

Treating the Proximal Interphalangeal Joint in Swan Neck and Boutonniere Deformities.

PubMed

Fox, Paige M; Chang, James

2018-05-01

Swan neck and boutonniere deformities of the proximal interphalangeal (PIP) joint are challenging to treat. In a swan neck deformity, the PIP joint is hyperextended with flexion at the distal interphalangeal (DIP) joint. In a boutonniere deformity, there is flexion the PIP joint with hyperextension of the DIP joint. When the deformities are flexible, treatment begins with splinting. However, when the deformity is fixed, serial casting or surgery is often necessary to restore joint motion before surgical correction. Many surgical techniques have been described to treat both conditions. Unfortunately, incomplete correction and deformity recurrence are common. Published by Elsevier Inc.

Optico-photographic measurements of airplane deformations

NASA Technical Reports Server (NTRS)

Kussner, Hans Georg

1931-01-01

The deformation of aircraft wings is measured by photographically recording a series of bright shots on a moving paper band sensitive to light. Alternating deformations, especially vibrations, can thus be measured in operation, unaffected by inertia. A handy recording camera, the optograph, was developed by the static division of the D.V.L. (German Experimental Institute for Aeronautics) for the employment of this method of measurement on airplanes in flight.

Application of the Deformation Information System for automated analysis and mapping of mining terrain deformations - case study from SW Poland

NASA Astrophysics Data System (ADS)

Blachowski, Jan; Grzempowski, Piotr; Milczarek, Wojciech; Nowacka, Anna

2015-04-01

Monitoring, mapping and modelling of mining induced terrain deformations are important tasks for quantifying and minimising threats that arise from underground extraction of useful minerals and affect surface infrastructure, human safety, the environment and security of the mining operation itself. The number of methods and techniques used for monitoring and analysis of mining terrain deformations is wide and expanding with the progress in geographical information technologies. These include for example: terrestrial geodetic measurements, Global Navigation Satellite Systems, remote sensing, GIS based modelling and spatial statistics, finite element method modelling, geological modelling, empirical modelling using e.g. the Knothe theory, artificial neural networks, fuzzy logic calculations and other. The presentation shows the results of numerical modelling and mapping of mining terrain deformations for two cases of underground mining sites in SW Poland, hard coal one (abandoned) and copper ore (active) using the functionalities of the Deformation Information System (DIS) (Blachowski et al, 2014 @ http://meetingorganizer.copernicus.org/EGU2014/EGU2014-7949.pdf). The functionalities of the spatial data modelling module of DIS have been presented and its applications in modelling, mapping and visualising mining terrain deformations based on processing of measurement data (geodetic and GNSS) for these two cases have been characterised and compared. These include, self-developed and implemented in DIS, automation procedures for calculating mining terrain subsidence with different interpolation techniques, calculation of other mining deformation parameters (i.e. tilt, horizontal displacement, horizontal strain and curvature), as well as mapping mining terrain categories based on classification of the values of these parameters as used in Poland. Acknowledgments. This work has been financed from the National Science Centre Project "Development of a numerical method of

Fluid flow in deforming media: interpreting stable isotope signatures of marbles

NASA Astrophysics Data System (ADS)

Bond, C. E.

2016-12-01

Fluid flow in the crust is controlled by permeable networks. These networks can be created and destroyed dynamically during rock deformation. Rock deformation is therefore critical in controlling fluid pathways in the crust and hence the location of mineral and other resources. Here, evidence for deformation-enhanced fluid infiltration shows that a range of deformation mechanisms control fluid flow and chemical and isotopic equilibration. The results attest to localised fluid infiltration within a single metamorphic terrain (12km) over a range of metamorphic grades; ecologite- blueschist to greenschist. For fluid infiltrating marbles during ductile deformation, chemical and isotopic signatures are now homogenous; whilst fluid infiltration associated with brittle deformation results in chemical and isotopic heterogeneity at a microscale. The findings demonstrate how ductile deformation enhances equilibration of δ18O at a grain scale whilst brittle deformation does not. The control of deformation mechanisms in equilibrating isotopic and chemical heterogeneities have implications for the understanding of fluid-rock interaction in the crust. Interpretation of bulk stable isotope data, particularly in the use of isotope profiles to determine fluid fluxes into relatively impermeable units that have been deformed need to be used with care when trying to determine fluid fluxes and infiltration mechanisms.

The Pic du Midi solar survey

NASA Astrophysics Data System (ADS)

Koechlin, L.

2015-12-01

We carry a long term survey of the solar activity with our coronagraphic system at Pic du Midi de Bigorre in the French Pyrenees (CLIMSO). It is a set of two solar telescopes and two coronagraphs, taking one frame per minute for each of the four channels : Solar disk in H-α (656.28 nm), prominences in H-α, disk in Ca II (393.3 nm), prominences in He I (1083 nm), all year long, weather permitting. Since 2015 we also take images of the FeXIII corona (1074.7 nm) at the rate of one every 10 minutes. These images cover a large field: 1.25 solar diameter, 2k*2K pixels, and are freely downloadable form a database. The improvements made since 2015 concern an autoguiding system for better centering of the solar disk behind the coronagraphic masks, and a new Fe XIII channel at λ=1074.7 nm. In the near future we plan to provide radial velocity maps of the disc and polarimetry maps of the disk and corona. This survey took its present form in 2007 and we plan to maintain image acquisition in the same or better experimental conditions for a long period: one or several solar cycles if possible. During the partial solar eclipse of March 20, 2015, the CLIMSO instruments and the staff at Pic du Midi operating it have provided several millions internet users with real time images of the Sun and Moon during all the phenomenon.

Thermoplastic composite parts manufacture at Du Pont

NASA Astrophysics Data System (ADS)

Medwin, Steven J.; Coyle, Edward J.

1993-01-01

Low-cost routes to the manufacture of complex shaped composite parts have been defined using metal forming techniques and Du Pont's long discontinuous fiber (LDF) Technology. These manufacturing techniques include roll forming, stretch forming, and press forming. Near equivalence between the static, dynamic, and damage tolerance properties of LDF and continuous fiber composites have been demonstrated. Several examples are cited which demonstrate the potential for this technology to significantly reduce the cost of aerospace components.

Deformation and evolution of an experimental drainage network subjected to oblique deformation: Insight from chi-maps

NASA Astrophysics Data System (ADS)

Guerit, Laure; Goren, Liran; Dominguez, Stéphane; Malavieille, Jacques; Castelltort, Sébastien

2017-04-01

The morphology of a fluvial landscape reflects a balance between its own dynamics and external forcings, and therefore holds the potential to reveal local or large-scale tectonic patterns. Commonly, particular focus has been cast on the longitudinal profiles of rivers as they constitute sensitive recorders of vertical movements, that can be recovered based on models of bedrock incision. However, several recent studies have suggested that maps of rescaled distance along channel called chi (χ), derived from the commonly observed power law relation between the slope and the drainage area , could reveal transient landscapes in state of reorganization of basin geometry and location of water divides. If river networks deforms in response to large amount of distributed strain, then they might be used to reconstruct the mode and rate of horizontal deformation away from major active structures through the use of the parameter χ. To explore how streams respond to tectonic horizontal deformation, we develop an experimental model for studying river pattern evolution over a doubly-vergent orogenic wedge growing in a context of oblique convergence. We use a series of sprinklers located about the experimental table to activate erosion, sediment transport and river development on the surface of the experimental wedge. At the end of the experiment, the drainage network is statistically rotated clockwise, confirming that rivers can record the distribution of motion along the wedge. However, the amount of rotation does not match with the imposed deformation, and thus we infer that stream networks are not purely passive markers. Based on the comparison between the observed evolution of the fluvial system and the predictions made from χ maps, we show that the plan-view morphology of the streams results from the competition between the imposed deformation and fluvial processes of drainage reorganization.

Deformability of Oxide Inclusions in Tire Cord Steels

NASA Astrophysics Data System (ADS)

Zhang, Lifeng; Guo, Changbo; Yang, Wen; Ren, Ying; Ling, Haitao

2018-04-01

The deformation of oxide inclusions in tire cord steels during hot rolling was analyzed, and the factors influencing their deformability at high and low temperatures were evaluated and discussed. The aspect ratio of oxide inclusions decreased with the increasing reduction ratio of the steel during hot rolling owing to the fracture of the inclusions. The aspect ratio obtained after the first hot-rolling process was used to characterize the high-temperature deformability of the inclusions. The deformation first increased and then decreased with the increasing (MgO + Al2O3)/(SiO2 + MnO) ratio of the inclusions. It also increased with the decreasing melting temperatures of the inclusions. Young's modulus was used to evaluate the low-temperature deformability of the inclusions. An empirical formula was fitted to calculate the Young's moduli of the oxides using the mean atomic volume. The moduli values of the inclusions causing wire fracture were significantly greater than the average. To reduce fracture in tire cord steel wires during cold drawing, it is proposed that inclusions be controlled to those with high SiO2 content and extremely low Al2O3 content. This proposal is based on the hypothesis that the deformabilities of oxides during cold drawing are inversely proportional to their Young's moduli. The future study thus proposed includes an experimental confirmation for the abovementioned predictions.

Measuring Viscoelastic Deformation with an Optical Mouse

ERIC Educational Resources Information Center

Ng, T. W.

2004-01-01

The feasibility of using an optical mouse to track the viscoelastic deformation of low-density polyethylene films that have a fixed attached load is presented. It is seen that using an optical mouse and with rudimentary experiment paraphernalia and arrangement, it is possible to get good measurements of viscoelastic deformation.

Ear molding in newborn infants with auricular deformities.

PubMed

Byrd, H Steve; Langevin, Claude-Jean; Ghidoni, Lorraine A

2010-10-01

A review of a single physician's experience in managing over 831 infant ear deformities (488 patients) is presented. The authors' methods of molding have advanced from the use of various tapes, glues, and stents, to a comprehensive yet simple system that shapes the antihelix, the triangular fossa, the helical rim, and the overly prominent conchal-mastoid angle (EarWell Infant Ear Correction System). The types of deformities managed, and their relative occurrence, are as follows: (1) prominent/cup ear, 373 ears (45 percent); (2) lidding/lop ear, 224 ears (27 percent); (3) mixed ear deformities, 83 ears (10 percent) (all had associated conchal crus); (4) Stahl's ear, 66 ears (8 percent); (5) helical rim abnormalities, 58 ears (7 percent); (6) conchal crus, 25 ears (3 percent); and (7) cryptotia, two ears (0.2 percent). Bilateral deformities were present in 340 patients (70 percent), with unilateral deformities in 148 patients (30 percent). Fifty-eight infant ears (34 patients) were treated using the final version of the EarWell Infant Ear Correction System with a success rate exceeding 90 percent (good to excellent results). The system was found to be most successful when begun in the first week of the infant's life. When molding was initiated after 3 weeks from birth, only approximately half of the infants had a good response. Congenital ear deformities are common and only approximately 30 percent self-correct. These deformities can be corrected by initiating appropriate molding in the first week of life. Neonatal molding reduces the need for surgical correction with results that often exceed what can be achieved with the surgical alternative.

Mechanics of deformations in terms of scalar variables

NASA Astrophysics Data System (ADS)

Ryabov, Valeriy A.

2017-05-01

Theory of particle and continuous mechanics is developed which allows a treatment of pure deformation in terms of the set of variables "coordinate-momentum-force" instead of the standard treatment in terms of tensor-valued variables "strain-stress." This approach is quite natural for a microscopic description of atomic system, according to which only pointwise forces caused by the stress act to atoms making a body deform. The new concept starts from affine transformation of spatial to material coordinates in terms of the stretch tensor or its analogs. Thus, three principal stretches and three angles related to their orientation form a set of six scalar variables to describe deformation. Instead of volume-dependent potential used in the standard theory, which requires conditions of equilibrium for surface and body forces acting to a volume element, a potential dependent on scalar variables is introduced. A consistent introduction of generalized force associated with this potential becomes possible if a deformed body is considered to be confined on the surface of torus having six genuine dimensions. Strain, constitutive equations and other fundamental laws of the continuum and particle mechanics may be neatly rewritten in terms of scalar variables. Giving a new presentation for finite deformation new approach provides a full treatment of hyperelasticity including anisotropic case. Derived equations of motion generate a new kind of thermodynamical ensemble in terms of constant tension forces. In this ensemble, six internal deformation forces proportional to the components of Irving-Kirkwood stress are controlled by applied external forces. In thermodynamical limit, instead of the pressure and volume as state variables, this ensemble employs deformation force measured in kelvin unit and stretch ratio.

Introduction of a deformable x-ray CT polymer gel dosimetry system

NASA Astrophysics Data System (ADS)

Maynard, E.; Heath, E.; Hilts, M.; Jirasek, A.

2018-04-01

This study introduces the first 3D deformable dosimetry system based on x-ray computed tomography (CT) polymer gel dosimetry and establishes the setup reproducibility, deformation characteristics and dose response of the system. A N-isopropylacrylamide (NIPAM)-based gel formulation optimized for x-ray CT gel dosimetry was used, with a latex balloon serving as the deformable container and low-density polyethylene and polyvinyl alcohol providing additional oxygen barrier. Deformable gels were irradiated with a 6 MV calibration pattern to determine dosimetric response and a dosimetrically uniform plan to determine the spatial uniformity of the response. Wax beads were added to each gel as fiducial markers to track the deformation and setup of the gel dosimeters. From positions of the beads on CT images the setup reproducibility and the limits and reproducibility of gel deformation were determined. Comparison of gel measurements with Monte Carlo dose calculations found excellent dosimetric accuracy, comparable to that of an established non-deformable dosimetry system, with a mean dose discrepancy of 1.5% in the low-dose gradient region and a gamma pass rate of 97.9% using a 3%/3 mm criterion. The deformable dosimeter also showed good overall spatial dose uniformity throughout the dosimeter with some discrepancies within 20 mm of the edge of the container. Tracking of the beads within the dosimeter found that sub-millimetre setup accuracy is achievable with this system. The dosimeter was able to deform and relax when externally compressed by up to 30 mm without sustaining any permanent damage. Internal deformations in 3D produced average marker movements of up to 12 mm along the direction of compression. These deformations were also shown to be reproducible over 100 consecutive deformations. This work has established several important characteristics of a new deformable dosimetry system which shows promise for future clinical applications, including the

Comparative study on different types of segmented micro deformable mirrors

NASA Astrophysics Data System (ADS)

Qiao, Dayong; Yuan, Weizheng; Li, Kaicheng; Li, Xiaoying; Rao, Fubo

2006-02-01

In an adaptive-optical (AO) system, the wavefront of optical beam can be corrected with deformable mirror (DM). Based on MicroElectroMechanical System (MEMS) technology, segmented micro deformable mirrors can be built with denser actuator spacing than continuous face-sheet designs and have been widely researched. But the influence of the segment structure has not been thoroughly discussed until now. In this paper, the design, performance and fabrication of several micromachined, segmented deformable mirror for AO were investigated. The wavefront distorted by atmospheric turbulence was simulated in the frame of Kolmogorov turbulence model. Position function was used to describe the surfaces of the micro deformable mirrors in working state. The performances of deformable mirrors featuring square, brick, hexagonal and ring segment structures were evaluated in criteria of phase fitting error, the Strehl ratio after wavefront correction and the design considerations. Then the micro fabrication process and mask layout were designed and the fabrication of micro deformable mirrors was implemented. The results show that the micro deformable mirror with ring segments performs the best, but it is very difficult in terms of layout design. The micro deformable mirrors with square and brick segments are easy to design, but their performances are not good. The micro deformable mirror with hexagonal segments has not only good performance in terms of phase fitting error, the Strehl ratio and actuation voltage, but also no overwhelming difficulty in layout design.

Contour junctions defined by dynamic image deformations enhance perceptual transparency.

PubMed

Kawabe, Takahiro; Nishida, Shin'ya

2017-11-01

The majority of work on the perception of transparency has focused on static images with luminance-defined contour junctions, but recent work has shown that dynamic image sequences with dynamic image deformations also provide information about transparency. The present study demonstrates that when part of a static image is dynamically deformed, contour junctions at which deforming and nondeforming contours are connected facilitate the deformation-based perception of a transparent layer. We found that the impression of a transparent layer was stronger when a dynamically deforming area was adjacent to static nondeforming areas than when presented alone. When contour junctions were not formed at the dynamic-static boundaries, however, the impression of a transparent layer was not facilitated by the presence of static surrounding areas. The effect of the deformation-defined junctions was attenuated when the spatial pattern of luminance contrast at the junctions was inconsistent with the perceived transparency related to luminance contrast, while the effect did not change when the spatial luminance pattern was consistent with it. In addition, the results showed that contour completions across the junctions were required for the perception of a transparent layer. These results indicate that deformation-defined junctions that involve contour completion between deforming and nondeforming regions enhance the perception of a transparent layer, and that the deformation-based perceptual transparency can be promoted by the simultaneous presence of appropriately configured luminance and contrast-other features that can also by themselves produce the sensation of perceiving transparency.

[Babies with cranial deformity].

PubMed

Feijen, Michelle M W; Claessens, Edith A W M Habets; Dovens, Anke J Leenders; Vles, Johannes S; van der Hulst, Rene R W J

2009-01-01

Plagiocephaly was diagnosed in a baby aged 4 months and brachycephaly in a baby aged 5 months. Positional or deformational plagio- or brachycephaly is characterized by changes in shape and symmetry of the cranial vault. Treatment options are conservative and may include physiotherapy and helmet therapy. During the last two decades the incidence of positional plagiocephaly has increased in the Netherlands. This increase is due to the recommendation that babies be laid on their backs in order to reduce the risk of sudden infant death syndrome. We suggest the following: in cases of positional preference of the infant, referral to a physiotherapist is indicated. In cases of unacceptable deformity of the cranium at the age 5 months, moulding helmet therapy is a possible treatment option.

Hot compression deformation behavior of AISI 321 austenitic stainless steel

NASA Astrophysics Data System (ADS)

Haj, Mehdi; Mansouri, Hojjatollah; Vafaei, Reza; Ebrahimi, Golam Reza; Kanani, Ali

2013-06-01

The hot compression behavior of AISI 321 austenitic stainless steel was studied at the temperatures of 950-1100°C and the strain rates of 0.01-1 s-1 using a Baehr DIL-805 deformation dilatometer. The hot deformation equations and the relationship between hot deformation parameters were obtained. It is found that strain rate and deformation temperature significantly influence the flow stress behavior of the steel. The work hardening rate and the peak value of flow stress increase with the decrease of deformation temperature and the increase of strain rate. In addition, the activation energy of deformation ( Q) is calculated as 433.343 kJ/mol. The microstructural evolution during deformation indicates that, at the temperature of 950°C and the strain rate of 0.01 s-1, small circle-like precipitates form along grain boundaries; but at the temperatures above 950°C, the dissolution of such precipitates occurs. Energy-dispersive X-ray analyses indicate that the precipitates are complex carbides of Cr, Fe, Mn, Ni, and Ti.

Estimation of contour motion and deformation for nonrigid object tracking

NASA Astrophysics Data System (ADS)

Shao, Jie; Porikli, Fatih; Chellappa, Rama

2007-08-01

We present an algorithm for nonrigid contour tracking in heavily cluttered background scenes. Based on the properties of nonrigid contour movements, a sequential framework for estimating contour motion and deformation is proposed. We solve the nonrigid contour tracking problem by decomposing it into three subproblems: motion estimation, deformation estimation, and shape regulation. First, we employ a particle filter to estimate the global motion parameters of the affine transform between successive frames. Then we generate a probabilistic deformation map to deform the contour. To improve robustness, multiple cues are used for deformation probability estimation. Finally, we use a shape prior model to constrain the deformed contour. This enables us to retrieve the occluded parts of the contours and accurately track them while allowing shape changes specific to the given object types. Our experiments show that the proposed algorithm significantly improves the tracker performance.

New Deformation-Induced Nanostructure in Silicon.

PubMed

Wang, Bo; Zhang, Zhenyu; Chang, Keke; Cui, Junfeng; Rosenkranz, Andreas; Yu, Jinhong; Lin, Cheng-Te; Chen, Guoxin; Zang, Ketao; Luo, Jun; Jiang, Nan; Guo, Dongming

2018-06-18

Nanostructures in silicon (Si) induced by phase transformations have been investigated during the past 50 years. Performances of nanostructures are improved compared to that of bulk counterparts. Nevertheless, the confinement and loading conditions are insufficient to machine and fabricate high-performance devices. As a consequence, nanostructures fabricated by nanoscale deformation at loading speeds of m/s have not been demonstrated yet. In this study, grinding or scratching at a speed of 40.2 m/s was performed on a custom-made setup by an especially designed diamond tip (calculated stress under the diamond tip in the order of 5.11 GPa). This leads to a novel approach for the fabrication of nanostructures by nanoscale deformation at loading speeds of m/s. A new deformation-induced nanostructure was observed by transmission electron microscopy (TEM), consisting of an amorphous phase, a new tetragonal phase, slip bands, twinning superlattices, and a single crystal. The formation mechanism of the new phase was elucidated by ab initio simulations at shear stress of about 2.16 GPa. This approach opens a new route for the fabrication of nanostructures by nanoscale deformation at speeds of m/s. Our findings provide new insights for potential applications in transistors, integrated circuits, diodes, solar cells, and energy storage systems.

Viscoelastic deformation of lipid bilayer vesicles†

PubMed Central

Wu, Shao-Hua; Sankhagowit, Shalene; Biswas, Roshni; Wu, Shuyang; Povinelli, Michelle L.

2015-01-01

Lipid bilayers form the boundaries of the cell and its organelles. Many physiological processes, such as cell movement and division, involve bending and folding of the bilayer at high curvatures. Currently, bending of the bilayer is treated as an elastic deformation, such that its stress-strain response is independent of the rate at which bending strain is applied. We present here the first direct measurement of viscoelastic response in a lipid bilayer vesicle. We used a dual-beam optical trap (DBOT) to stretch 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC) giant unilamellar vesicles (GUVs). Upon application of a step optical force, the vesicle membrane deforms in two regimes: a fast, instantaneous area increase, followed by a much slower stretching to an eventual plateau deformation. From measurements of dozens of GUVs, the average time constant of the slower stretching response was 0.225 ± 0.033 s (standard deviation, SD). Increasing the fluid viscosity did not affect the observed time constant. We performed a set of experiments to rule out heating by laser absorption as a cause of the transient behavior. Thus, we demonstrate here that the bending deformation of lipid bilayer membranes should be treated as viscoelastic. PMID:26268612

Deformation of a micro-torque swimmer

PubMed Central

Ishikawa, Takuji; Tanaka, Tomoyuki; Imai, Yohsuke; Omori, Toshihiro; Matsunaga, Daiki

2016-01-01

The membrane tension of some kinds of ciliates has been suggested to regulate upward and downward swimming velocities under gravity. Despite its biological importance, deformation and membrane tension of a ciliate have not been clarified fully. In this study, we numerically investigated the deformation of a ciliate swimming freely in a fluid otherwise at rest. The cell body was modelled as a capsule with a hyperelastic membrane enclosing a Newtonian fluid. Thrust forces due to the ciliary beat were modelled as torques distributed above the cell body. The effects of membrane elasticity, the aspect ratio of the cell's reference shape, and the density difference between the cell and the surrounding fluid were investigated. The results showed that the cell deformed like a heart shape, when the capillary number was sufficiently large. Under the influence of gravity, the membrane tension at the anterior end decreased in the upward swimming while it increased in the downward swimming. Moreover, gravity-induced deformation caused the cells to move gravitationally downwards or upwards, which resulted in a positive or negative geotaxis-like behaviour with a physical origin. These results are important in understanding the physiology of a ciliate's biological responses to mechanical stimuli. PMID:26997893

An algorithmic approach to crustal deformation analysis

NASA Technical Reports Server (NTRS)

Iz, Huseyin Baki

1987-01-01

In recent years the analysis of crustal deformation measurements has become important as a result of current improvements in geodetic methods and an increasing amount of theoretical and observational data provided by several earth sciences. A first-generation data analysis algorithm which combines a priori information with current geodetic measurements was proposed. Relevant methods which can be used in the algorithm were discussed. Prior information is the unifying feature of this algorithm. Some of the problems which may arise through the use of a priori information in the analysis were indicated and preventive measures were demonstrated. The first step in the algorithm is the optimal design of deformation networks. The second step in the algorithm identifies the descriptive model of the deformation field. The final step in the algorithm is the improved estimation of deformation parameters. Although deformation parameters are estimated in the process of model discrimination, they can further be improved by the use of a priori information about them. According to the proposed algorithm this information must first be tested against the estimates calculated using the sample data only. Null-hypothesis testing procedures were developed for this purpose. Six different estimators which employ a priori information were examined. Emphasis was put on the case when the prior information is wrong and analytical expressions for possible improvements under incompatible prior information were derived.

W.E.B. DuBois's Challenge to Scientific Racism.

ERIC Educational Resources Information Center

Taylor, Carol M.

1981-01-01

Proposes that a direct and authoritative challenge to the scientific racism of the late eighteenth and early twentieth centuries was urgently needed, and was one of the leading rhetorical contributions of W.E.B. DuBois. Specifically examines three issues: social Darwinism, the eugenics movement, and psychologists' measurement of intelligence.…

L’effet du yoga chez les patients atteints de cancer

PubMed Central

Côté, Andréanne; Daneault, Serge

2012-01-01

Résumé Objectif Déterminer si le yoga thérapeutique améliore la qualité de vie de patients atteints de cancer. Sources des données Recherche effectuée avec la base de données MEDLINE (1950–2010) en utilisant les mots-clés yoga, cancer et quality of life. Sélection des études Priorité accordée aux études cliniques randomisées contrôlées évaluant l’effet du yoga sur différents symptômes susceptibles de se présenter chez des patients atteints de cancer en Amérique du Nord. Synthèse Quatre études cliniques randomisées contrôlées ont d’abord été analysées, puis 2 études sans groupe-contrôle. Trois études réalisées en Inde et au Proche-Orient ont également apporté des éléments intéressants au plan méthodologique. Les interventions proposées comprenaient des séances de yoga d’une durée et d’une fréquence variables. Les paramètres mesurés variaient également d’une étude à l’autre. Plusieurs symptômes ont connu des améliorations significatives avec le yoga (meilleure qualité du sommeil, diminution des symptômes anxieux ou dépressifs, amélioration du bien-être spirituel, etc.). Il a aussi semblé que la qualité de vie, dans sa globalité ou dans certaines de ses composantes spécifiques, s’améliorait. Conclusion La variété des effets bénéfiques produits, l’absence d’effet secondaire et le rapport coût-bénéfice avantageux du yoga thérapeutique en fait une intervention intéressante à suggérer par les médecins de famille aux patients atteints de cancer. Certaines lacunes méthodologiques ont pu diminuer la puissance statistique des études présentées, à commencer par la taille restreinte des échantillons et par l’assiduité variable des patients soumis à l’intervention. Il est également possible que les échelles de mesure utilisées ne convenaient pas à ce type de situation et de clientèle pour qu’en soit dégagé un effet significatif. Toutefois, les commentaires

Efavirenz DuPont Pharmaceuticals Co.

PubMed

Dong, B J

1998-10-01

Efavirenz is the lead compound of a series of benzoxazinones originally developed by DuPont Merck. It is a non-nucleoside reverse transcriptase inhibitor (NNRTI) under development for the potential treatment of viral infections, including HIV. In June 1998, the company submitted an NDA to the US FDA for the use of efavirenz (as Sustiva) for the treatment of HIV infection [289361]. In July 1998, DuPont purchased Merck's interest in DuPont Merck and the company's name changed to DuPont Pharmaceuticals. The two companies decided to continue to share marketing rights to Sustiva (to be marketed by Merck as Stocrin outside the US, Canada, and certain European countries) [291738]. As of October 1997, triple combination studies of efavirenz were ongoing, or planned, with nelfinavir, indinavir or ritonavir, or other retroviral inhibitors, for the treatment of opportunistic and pediatric viral infections [265945]. Efavirenz is also being evaluated as monotherapy and in combination with zidovudine (Retrovir, AZT) and lamivudine (Epivir, 3TC) (qv). Results of a study in eight HIV-infected patients, reported at the 12th World AIDS Conference in July 1998, showed that efavirenz administration, in dual and triple combinations, achieved HIV-RNA levels in plasma and cerebrospinal fluid (CSF) below the level of detection (fewer than 400 copies/ml) [290881,293994]. In March 1998, Merck signed a letter of intent with Trimeris to conduct a trial of efavirenz in combination with Trimeris's HIV fusion inhibitor, T-20, (qv). The trial will enroll up to 48 HIV-infected individuals at three sites in the US. All enrolled patients will be those who have begun to fail their existing triple combination therapy. Prior exposure to NNRTIs and protease inhibitors, other than indinavir, will be among the exclusion criteria for the study. The first 10 days of the study were planned as a dose-optimization period to assess the safety, pharmacokinetics and antiviral activity of multiple ascending doses

Up-regulating of RASD1 and apoptosis of DU-145 human prostate cancer cells induced by formononetin in vitro.

PubMed

Liu, Xiao-Jia; Li, Yun-Qian; Chen, Qiu-Yue; Xiao, Sheng-Jun; Zeng, Si-En

2014-01-01

Prostate cancer is one of the most prevalent malignant cancers in men. The isoflavone formononetin is a main active component of red clover plants. In the present study, we assessed the effect of formononetin on human prostate cancer DU-145 cells in vitro, and elucidated possible mechanisms. DU-145 cells were treated with different concentrations of formononetin and cell proliferation was assessed by MTT assay, cell apoptosis by Hoechst 33258 and flow cytometry, and protein levels of RASD1, Bcl-2 and Bax by Western blotting. The results showed that formononetin inhibited the proliferation of DU-145 cells in a dose-dependent manner. DU-145 cells treated with different concentrations of formononetin displayed obvious morphological changes of apoptosis under fluorescence microscopy. In addition, formononetin increased the proportion of early apoptotic DU-145 cells, down-regulated the protein levels of Bcl-2 and up-regulated those of RASD1 and Bax. The level of RASD1 reached its maximum at 48 h post-treatment, and rapidly decreased thereafter. Together, we present evidence that formononetin triggered cell apoptosis through the mitochondrial apoptotic pathway by up-regulating RASD1.

Droplet Deformation Prediction With the Droplet Deformation and Breakup Model (DDB)

NASA Technical Reports Server (NTRS)

Vargas, Mario

2012-01-01

The Droplet Deformation and Breakup Model was used to predict deformation of droplets approaching the leading edge stagnation line of an airfoil. The quasi-steady model was solved for each position along the droplet path. A program was developed to solve the non-linear, second order, ordinary differential equation that governs the model. A fourth order Runge-Kutta method was used to solve the equation. Experimental slip velocities from droplet breakup studies were used as input to the model which required slip velocity along the particle path. The center of mass displacement predictions were compared to the experimental measurements from the droplet breakup studies for droplets with radii in the range of 200 to 700 mm approaching the airfoil at 50 and 90 m/sec. The model predictions were good for the displacement of the center of mass for small and medium sized droplets. For larger droplets the model predictions did not agree with the experimental results.

Lateral column length in adult flatfoot deformity.

PubMed

Kang, Steve; Charlton, Timothy P; Thordarson, David B

2013-03-01

In adult acquired flatfoot deformity, it is unclear whether the lateral column length shortens with progression of the deformity, whether it is short to begin with, or whether it is short at all. To our knowledge, no previous study has examined the lateral column length of patients with adult acquired flatfoot deformity compared to a control population. The purpose of our study was to compare the lateral column length in patients with and without adult acquired flatfoot deformity to see if there was a significant difference. The study was a retrospective radiographic review of 2 foot and ankle fellowship-trained orthopaedic surgeons' patients with adult flatfoot deformity. Our study population consisted of 75 patients, 85 feet (28 male, 57 female) with adult flatfoot deformity with a mean age of 64 (range, 23-93). Our control population consisted of 57 patients and 70 feet (23 male, 47 female) without flatfoot deformity with a mean age of 61 (range, 40-86 years). Weightbearing anteroposterior (AP) and lateral foot radiographs were analyzed for each patient, and the following measurements were made: medial and lateral column lengths, talonavicular uncoverage angle, talus-first metatarsal angle, calcaneal pitch angle, and medial and lateral column heights. An unpaired t test was used to analyze the measurements between the groups. Ten patients' radiographs were remeasured, and correlation coefficients were obtained to assess the reliability of the measuring techniques. For the flatfoot group, the mean medial and lateral column lengths on the AP radiograph were 108.6 mm and 95.8 mm, respectively; the mean talo-navicular uncoverage angle was 26.2 degrees; and the mean talus-first metatarsal angle was 20.0 degrees. In the control group, the mean medial and lateral column lengths on the AP radiograph were 108.8 mm and 96.5 mm, respectively; the mean talo-navicular uncoverage angle was 8.2 degrees; and the mean talus-first metatarsal angle was 7.7 degrees. On the lateral

Lattice preferred orientation of hcp-iron induced by shear deformation

NASA Astrophysics Data System (ADS)

Nishihara, Y.; Ohuchi, T.; Kawazoe, T.; Maruyama, G.; Higo, Y.; Funakoshi, K. I.; Seto, Y.

2015-12-01

Many hypotheses have been proposed for origin of seismic anisotropy in the Earth's inner core which consists of solid metal. Plastic deformation of constituent material (most probably hexagonal-close-packed (hcp) iron) is one of the candidate processes to form the inner core anisotropy. Thus knowledge of deformation-induced lattice preferred orientation (LPO) of hcp-iron is important for understanding of nature of the inner core. In this study, we have carried out shear deformation experiments on hcp-iron and determined its deformation induced LPO. Since it is impossible to recover hcp-iron to ambient condition, both deformation and measurement of LPO have to be done at high-pressure conditions. Shear deformation experiments of hcp-iron were carried out using a deformation-DIA apparatus at high-pressure and high-temperature condition where hcp-iron is stable (9-18 GPa, 723 K). Development of LPO in the deforming sample was observed in-situ based on two-dimensional X-ray diffraction using an imaging plate detector and monochromatized synchrotron X-ray. In shear deformation of hcp-iron, <0001> and <112‾0> axes gradually aligned to be sub-parallel to shear plane normal and shear direction, respectively, from initial random orientation. The <0001> and <112‾0> axes are back-rotated from shear direction by 30°. The above results suggest basal slip <112‾0>{0001} is the dominant slip system under the studied deformation conditions. It has been shown that Earth's inner core has an axisymmetric anisotropy with P-wave traveling 3% faster along polar paths than along equatorial directions. Although elastic anisotropy of hcp-iron at the inner core conditions is still controversial, recent theoretical studies consistently shows that P-wave velocity of hcp-iron is fastest along <0001> direction at least at low-temperatures. Our experimental results could be suggesting that most part of the inner core deforms with shear plane sub-parallel to equatorial plane.

L’identification et traitement du trouble panique avec ou sans agoraphobie

PubMed Central

Foldes-Busque, Guillaume; Marchand, André; Landry, Pierre

2007-01-01

RÉSUMÉ OBJECTIF Renseigner les médecins de première ligne au sujet de l’identification précoce, du diagnostic et du traitement du trouble panique avec ou sans agoraphobie (TP/A). QUALITÉ DES DONNÉES Les données et recommandations présentées proviennent d’une recension des écrits scientifiques réalisée via les banques de données PsycLIT, PsyINFO et MEDLINE (1985 à 2006) en utilisant les descripteurs panic disorder, psychotherapy, psychosocial treatment, treatment et pharmacotherapy. Les recommandations formulées par les auteurs s’appuient sur des données probantes provenant d’études d’excellente qualité. Les informations concernant le diagnostic et l’évaluation du TP/A proviennent d’études épidémiologiques récentes, de consensus et d’opinions d’experts. PRINCIPAL MESSAGE Le TP/A est un trouble psychiatrique souvent rencontré en médecine de première ligne, mais il est fréquemment sous-diagnostiqué et sous-traité. L’identification précoce de ce trouble demande une attention particulière aux symptômes médicalement inexpliqués et, le cas échéant, le médecin doit utiliser des questions spécifiques permettant d’identifier d’éventuelles attaques de panique et de cerner leur signification pour le patient. Le traitement de premier choix pour ce trouble est une psychothérapie d’orientation cognitivo-comportementale administrée par un psychologue ou un psychiatre spécialisé. Si de telles ressources ne sont pas disponibles, le médecin peut opter pour un traitement psychopharmacologique. CONCLUSION Les médecins de famille peuvent jouer un rôle central dans l’identification et le traitement des patients souffrant d’un TP/A. PMID:17934032

How deformed are the TSD bands in odd Lu isotopes?

NASA Astrophysics Data System (ADS)

Ragnarsson, I.

2017-12-01

The experimental fingerprints for large deformation in the triaxial strongly deformed (TSD) bands of 163,165,167Lu are discussed. It is argued that these fingerprints are not very convincing. On the contrary, especially the fact that there exist strong interactions between the TSD bands and normal-deformed (ND) bands indicates that the deformation of the TSD bands cannot be very different from that of the ND bands. The need for detailed new experimental data is underlined.

Deformation and Breakup of Two Fluid Jets

NASA Astrophysics Data System (ADS)

Doshi, Pankaj; Ramkrishna, Doraiswamy; Basaran, Osman

2001-11-01

Two fluid jets consists of an inner liquid core surrounded by an annulus of outer immiscible liquid. The perturbation in the inner and outer interphase could cause capillary instability resulting in large deformation and breakup of the jet into drops. The jet breakup and drop size distribution is largely influenced by the properties of inner and outer fluid phases. Out of the various jet breakup phenomena one with most technological importance is the one in which inner interphase ruptures followed by the outer interphase resulting in the formation of compound drops. The compound drop formation is very useful for the microencapsulation technology, which find use in diverse pharmaceutical and chemical industry applications. In this paper we present a computational analysis of non-linear deformation and breakup of two fluid jets of Newtonian fluids. The analysis involves study of capillary instability driven deformation of a free jet with periodic boundary conditions. Although small amplitude deformation of two fluid jets have previously been studied, large amplitude deformation exhibiting interesting nonlinear dynamics and eventual breakup of the two fluid jets have been beyond the reach of previously used analytical and computational techniques. The computational difficulties result from the facts that (1) the inner and outer interphase can overturn during the motion and (2) pressure and normal stress are discontinuous at the inner interphase. We overcome both of these difficulties by using a new Galerkin/finite element algorithm that relies on a powerful elliptic mesh generation technique. The results to be presented includes jet deformation and breakup time as a function of inner and outer fluid phase properties. The highlight of the results will be prediction of drop size distribution which is of critical importance for microencapsulation technology.

Global tectonic reconstructions with continuously deforming and evolving rigid plates

NASA Astrophysics Data System (ADS)

Gurnis, Michael; Yang, Ting; Cannon, John; Turner, Mark; Williams, Simon; Flament, Nicolas; Müller, R. Dietmar

2018-07-01

Traditional plate reconstruction methodologies do not allow for plate deformation to be considered. Here we present software to construct and visualize global tectonic reconstructions with deforming plates within the context of rigid plates. Both deforming and rigid plates are defined by continuously evolving polygons. The deforming regions are tessellated with triangular meshes such that either strain rate or cumulative strain can be followed. The finite strain history, crustal thickness and stretching factor of points within the deformation zones are tracked as Lagrangian points. Integrating these tools within the interactive platform GPlates enables specialized users to build and refine deforming plate models and integrate them with other models in time and space. We demonstrate the integrated platform with regional reconstructions of Cenozoic western North America, the Mesozoic South American Atlantic margin, and Cenozoic southeast Asia, embedded within global reconstructions, using different data and reconstruction strategies.

Crustal deformation along the San Andreas, California

NASA Technical Reports Server (NTRS)

Li, Victor C.

1992-01-01

The goal is to achieve a better understanding of the regional and local deformation and crustal straining processes in western North America, particularly the effects of the San Andreas and nearby faults on the spatial and temporal crustal deformation behavior. Construction of theoretical models based on the mechanics of coupled elastic plate, viscoelastic foundation and large scale crack mechanics provide a rational basis for the interpretation of seismic and aseismic anomalies and expedite efforts in forecasting the stability of plate boundary deformation. Special focus is placed on the three dimensional time dependent surface deformation due to localized slippage in a elastic layer coupled to a visco-elastic substrate. The numerical analysis is based on a 3-D boundary element technique. Extension to visco-elastic coupling demands the derivation of 3-D time dependent Green's function. This method was applied to analyze the viscoelastic surface displacements due to a dislocated embedded patch. Surface uplift as a function of time and position are obtained. Comparisons between surface uplift for long and short dislocated patches are made.

Research in rock deformation: Report of the Second Rock Deformation Colloquium, 1989 AGU Spring Meeting

NASA Astrophysics Data System (ADS)

Green, Harry

In response to the considerable interest expressed at the first Rock Deformation Colloquium held at the Fall 1988 AGU meeting in San Francisco, a second dinner meeting was held on Monday evening, May 8, 1989, at the Omni Hotel in Baltimore. The principal business items were a report by Steve Kirby (U.S. Geological Survey, Menlo Park, Calif.) concerning the meeting the previous day of the rock deformation steering committee and an after dinner presentation by Steve Freiman of the National Institute of Standards and Technology in Gaithersburg, Md., entitled “The Environmental Effects on Subcritical Crack Growth.” Kirby reported that a technical committee for rock deformation has been established within the Tectonophysics Section of AGU; the steering committee will attempt to establish constructive working relations with allied societies and disciplines, such as ceramics, metallurgy, materials science, structural geology, and surface science. Brian Evans of the Massachusetts Institute of Technology in Cambridge, Terry Tullis of Brown University in Providence, R.I., and Harry Green of the University of California at Davis agreed to be a subcommittee to propose a name for the technical committee, for discussion at the next steering committee meeting to be held before the 1989 Fall AGU meeting. Green also agreed to investigate the possibility of convening a special session at the Fall Meeting on the nature and mechanism of deep-focus earthquakes. (The session is Deep Slab Deformation and Faulting, T21B and T22A, organized by Harry and Ken Creager of the University of Washington, Seattle; it will be all day on Tuesday, December 5.)

Swinging motion of active deformable particles in Poiseuille flow

NASA Astrophysics Data System (ADS)

Tarama, Mitsusuke

2017-08-01

Dynamics of active deformable particles in an external Poiseuille flow is investigated. To make the analysis general, we employ time-evolution equations derived from symmetry considerations that take into account an elliptical shape deformation. First, we clarify the relation of our model to that of rigid active particles. Then, we study the dynamical modes that active deformable particles exhibit by changing the strength of the external flow. We emphasize the difference between the active particles that tend to self-propel parallel to the elliptical shape deformation and those self-propelling perpendicularly. In particular, a swinging motion around the centerline far from the channel walls is discussed in detail.

Intrafraction Variability and Deformation Quantification in the Breast

DOE Office of Scientific and Technical Information (OSTI.GOV)

Glide-Hurst, Carri K., E-mail: churst2@hfhs.org; Shah, Mira M.; Price, Ryan G.

2015-03-01

Purpose: To evaluate intrafraction variability and deformation of the lumpectomy cavity (LC), breast, and nearby organs. Methods and Materials: Sixteen left-sided postlumpectomy and 1 bilateral breast cancer cases underwent free-breathing CT (FBCT) and 10-phase 4-dimensional CT (4DCT). Deformable image registration was used for deformation analysis and contour propagation of breast, heart, lungs, and LC between end-exhale and end-inhale 4DCT phases. Respiration-induced motion was calculated via centroid analysis. Two planning target volumes (PTVs) were compared: PTV{sub FBCT} from the FBCT volume with an isotropic 10 mm expansion (5 mm excursion and 5 mm setup error) and PTV{sub 4DCT} generated from themore » union of 4DCT contours with isotropic 5 mm margin for setup error. Volume and geometry were evaluated via percent difference and bounding box analysis, respectively. Deformation correlations between breast/cavity, breast/lung, and breast/heart were evaluated. Associations were tested between cavity deformation and proximity to chest wall and breast surface. Results: Population-based 3-dimensional vector excursions were 2.5 ± 1.0 mm (range, 0.8-3.8 mm) for the cavity and 2.0 ± 0.8 mm (range, 0.7-3.0 mm) for the ipsilateral breast. Cavity excursion was predominantly in the anterior and superior directions (1.0 ± 0.8 mm and −1.8 ± 1.2 mm, respectively). Similarly, for all cases, LCs and ipsilateral breasts yielded median deformation values in the superior direction. For 14 of 17 patients, the LCs and breast interquartile ranges tended toward the anterior direction. The PTV{sub FBCT} was 51.5% ± 10.8% larger (P<.01) than PTV{sub 4DCT}. Bounding box analysis revealed that PTV{sub FBCT} was 9.8 ± 1.2 (lateral), 9.0 ± 2.2 (anterior–posterior), and 3.9 ± 1.8 (superior–inferior) mm larger than PTV{sub 4DCT}. Significant associations between breast and cavity deformation were found for 6 of 9 axes. No dependency was found between

Aerodynamic effects of corrugation and deformation in flapping wings of hovering hoverflies.

PubMed

Du, Gang; Sun, Mao

2012-05-07

We investigated the aerodynamic effects of wing deformation and corrugation of a three-dimensional model hoverfly wing at a hovering condition by solving the Navier-Stokes equations on a dynamically deforming grid. Various corrugated wing models were tested. Insight into whether or not there existed significant aerodynamic coupling between wing deformation (camber and twist) and wing corrugation was obtained by comparing aerodynamic forces of four cases: a smooth-plate wing in flapping motion without deformation (i.e. a rigid flat-plate wing in flapping motion); a smooth-plate wing in flapping motion with deformation; a corrugated wing in flapping motion without deformation (i.e. a rigid corrugated wing in flapping motion); a corrugated wing in flapping motion with deformation. There was little aerodynamic coupling between wing deformation and corrugation: the aerodynamic effect of wing deformation and corrugation acting together was approximately a superposition of those of deformation and corrugation acting separately. When acting alone, the effect of wing deformation was to increase the lift by 9.7% and decrease the torque (or aerodynamic power) by 5.2%, and that of wing corrugation was to decrease the lift by 6.5% and increase the torque by 2.2%. But when acting together, the wing deformation and corrugation only increased the lift by ~3% and decreased the torque by ~3%. That is, the combined aerodynamic effect of deformation and corrugation is rather small. Thus, wing corrugation is mainly for structural, not aerodynamic, purpose, and in computing or measuring the aerodynamic forces, using a rigid flat-plate wing to model the corrugated deforming wing at hovering condition can be a good approximation. Copyright © 2012 Elsevier Ltd. All rights reserved.

Plastic deformation in a metallic granular chain

NASA Astrophysics Data System (ADS)

Musson, Ryan W.; Carlson, William

2016-03-01

Solitary wave response was investigated in a metallic granular chain-piston system using LS-DYNA. A power law hardening material model was used to show that localized plastic deformation is present in a metallic granular chain for an impact velocity of 0.5 m/s. This loss due to plastic deformation was quantified via impulse, and it was shown that the loss scales nearly linearly with impact velocity. Therefore, metallic grains may not be suitable for devices that require high-amplitude solitary waves. There would be too much energy lost to plastic deformation. One can assume that ceramics will behave elastically; therefore, the response of an aluminum oxide granular chain was compared to that of a steel chain.

Impacts de l`élévation du niveau de la mer sur l'évolution future d'une côte basse à lagune de la péninsule du Cap Bon (Nord-Est de la Tunisie): approche cartographique

NASA Astrophysics Data System (ADS)

Brahmi, Noura; Dhieb, Mohsen; Chedly Rabia, Mohamed

2018-05-01

La submersion marine est l'une des principales menaces qui pèsent sur les zones humides littorales de la péninsule du Cap Bon. Or, cette menace est amenée à se renforcer en raison du réchauffement climatique qui entraînera une élévation du niveau marin et vraisemblablement un renforcement de l'intensité des tempêtes et des cyclones tropicaux d'ici à l'horizon 2100. L'objectif a donc été d'évaluer la vulnérabilité de la lagune face à la submersion. Dans cette optique, après avoir identifié les enjeux liés à l'élévation du niveau de la mer pour la lagune, nous avons dressé une cartographie prévisionnelle des risques de submersion par l'intermédiaire d'une application cartographique basée sur une modélisation numérique de terrain et analysé les impacts potentiels de ce phénomène. La cartographie est donc amenée à devenir centrale pour l'étude de l'impact du risque de la submersion marine sur les lagunes côtières et la gestion de ces espaces dans les décennies à venir. La cartographie de l'aléa submersion marine a montré que l'ouverture épisodique de brèches lors des tempêtes pourrait entraîner la submersion de l'ensemble du domaine lagunaire et aurait un impact morphogénique essentiel. En effet, le phénomène d'une accélération de l'élévation du niveau marin et d'un renforcement des tempêtes génère le morcellement du cordon littoral qui sépare la lagune de la mer. Par ailleurs, les pertes de matériel sédimentaire pour la plage augmenteront, dans la mesure où, lors d'une tempête, une grande partie des matériaux déplacés par les vagues dans les étangs par submersion ou par ouverture d'une brèche, ne peut être récupérée par la suite. Tout ceci constitue un facteur d'accélération du recul ou de disparition de la plage déjà très érodée. Les impacts de cette submersion pourraient être importants en absence de mesures préventives. Elle aurait ainsi des répercussions profondes sur les syst

Structural defects in natural plastically deformed diamonds: Evidence from EPR spectroscopy

NASA Astrophysics Data System (ADS)

Mineeva, R. M.; Titkov, S. V.; Speransky, A. V.

2009-06-01

Structural defects formed as a result of plastic deformation in natural diamond crystals have been studied by EPR spectroscopy. The spectra of brown, pink-brown, black-brown, pink-purple, and gray plastically deformed diamonds of type Ia from deposits in Yakutia and the Urals were recorded. The results of EPR spectroscopy allowed us to identify various deformation centers in the structure of natural diamonds and to show that nitrogen centers were transformed under epigenetic mechanical loading. Abundant A centers, consisting of two isomorphic nitrogen atoms located in neighboring structural sites, were destroyed as a result of this process to form a series of N1, N4, W7, M2, and M3 nitrogen centers. Such centers are characterized by an anisotropic spatial distribution and a positive charge, related to the mechanism of their formation. In addition, N2 centers (probably, deformation-produced dislocations decorated by nitrogen) were formed in all plastically deformed diamonds and W10 and W35 centers (the models have not been finally ascertained) were formed in some of them. It has been established that diamonds with various types of deformation-induced color contain characteristic associations of these deformation centers. The diversity of associations of deformation centers indicates appreciable variations in conditions of disintegration of deep-seated rocks, transfer of diamonds to the Earth’s surface, and formation of kimberlitic deposits. Depending on the conditions of mechanical loading, the diamond crystals were plastically deformed by either dislocation gliding or mechanical twinning. Characteristic features of plastic deformation by dislocation gliding are the substantial prevalence of the N2 centers over other deformation centers and the occurrence of the high-spin W10 and W35 centers. The attributes of less frequent plastic deformation by mechanical twinning are unusual localization of the M2 centers and, in some cases, the N1 centers in microtwinned

Deformation of phospholipid vesicles in an optical stretcher.

PubMed

Delabre, Ulysse; Feld, Kasper; Crespo, Eleonore; Whyte, Graeme; Sykes, Cecile; Seifert, Udo; Guck, Jochen

2015-08-14

Phospholipid vesicles are common model systems for cell membranes. Important aspects of the membrane function relate to its mechanical properties. Here we have investigated the deformation behaviour of phospholipid vesicles in a dual-beam laser trap, also called an optical stretcher. This study explicitly makes use of the inherent heating present in such traps to investigate the dependence of vesicle deformation on temperature. By using lasers with different wavelengths, optically induced mechanical stresses and temperature increase can be tuned fairly independently with a single setup. The phase transition temperature of vesicles can be clearly identified by an increase in deformation. In the case of no heating effects, a minimal model for drop deformation in an optical stretcher and a more specific model for vesicle deformation that takes explicitly into account the angular dependence of the optical stress are presented to account for the experimental results. Elastic constants are extracted from the fitting procedures, which agree with literature data. This study demonstrates the utility of optical stretching, which is easily combined with microfluidic delivery, for the future serial, high-throughput study of the mechanical and thermodynamic properties of phospholipid vesicles.

Optimizing Cubature for Efficient Integration of Subspace Deformations

PubMed Central

An, Steven S.; Kim, Theodore; James, Doug L.

2009-01-01

We propose an efficient scheme for evaluating nonlinear subspace forces (and Jacobians) associated with subspace deformations. The core problem we address is efficient integration of the subspace force density over the 3D spatial domain. Similar to Gaussian quadrature schemes that efficiently integrate functions that lie in particular polynomial subspaces, we propose cubature schemes (multi-dimensional quadrature) optimized for efficient integration of force densities associated with particular subspace deformations, particular materials, and particular geometric domains. We support generic subspace deformation kinematics, and nonlinear hyperelastic materials. For an r-dimensional deformation subspace with O(r) cubature points, our method is able to evaluate subspace forces at O(r2) cost. We also describe composite cubature rules for runtime error estimation. Results are provided for various subspace deformation models, several hyperelastic materials (St.Venant-Kirchhoff, Mooney-Rivlin, Arruda-Boyce), and multimodal (graphics, haptics, sound) applications. We show dramatically better efficiency than traditional Monte Carlo integration. CR Categories: I.6.8 [Simulation and Modeling]: Types of Simulation—Animation, I.3.5 [Computer Graphics]: Computational Geometry and Object Modeling—Physically based modeling G.1.4 [Mathematics of Computing]: Numerical Analysis—Quadrature and Numerical Differentiation PMID:19956777

Place du traitement chirurgical sous circulation extracorporelle à cœur battant dans les cancers du rein avec envahissement cave supra-diaphragmatique: à propos de sept cas

PubMed Central

Lahyani, Mounir; Karmouni, Tarik; Elkhader, Khalid; Koutani, Abdellatif; Andaloussi, Ahmed Ibn Attya

2014-01-01

Ce travail vise à analyser les résultats de la néphrectomie avec thrombectomie atrio-cave sous circulation extracorporelle (CEC) chez sept patients ayant un cancer du rein avec envahissement cave supra-diaphragmatique et de discuter les indications opératoires. Sept patients, six hommes et une femme dont l’âge varie entre 46ans et 65ans, ont été opérés d'un cancer du rein avec extension atrio-cave. L’écho-doppler a toujours permis la mise en évidence de l'extension veineuse mais la limite supérieure du thrombus était formellement identifiée par l'examen tomodensitométrique quatre fois, et par la résonance magnétique nucléaire dans tous les cas. Tous les patients ont été opérés sous CEC à cœur battant en normothermie. Un seul décès postopératoire est survenu. La durée du séjour en réanimation a été de 4,5 jours. Cinq patients ont eu à distance une dissémination métastatique. Cinq malades ont eu une médiane de survie de 11,5 mois (de 7 à16). Un malade a subi une métastasectomie pulmonaire 6 mois après la néphrectomie. L'exérèse des thrombi atrio-caves a été facilitée par la CEC avec une mortalité et une morbidité postopératoires acceptables mais les résultats à distance ont été décevants. Cette intervention ne peut être proposée qu'aux patients n'ayant aucune extension locorégionale et générale décelable, ce qui souligne l'importance des examens morphologiques préopératoires. PMID:25995777

Measurement of shape and deformation of insect wing

NASA Astrophysics Data System (ADS)

Yin, Duo; Wei, Zhen; Wang, Zeyu; Zhou, Changqiu

2018-01-01

To measure the shape and deformation of an insect wing, a scanning setup adopting laser triangulation and image matching was developed. Only one industry camera with two light sources was employed to scan the transparent insect wings. 3D shape and point to point full field deformation of the wings could be obtained even when the wingspan is less than 3 mm. The venation and corrugation could be significantly identified from the results. The deformation of the wing under pin loading could be seen clearly from the results as well. Calibration shows that the shape and deformation measurement accuracies are no lower than 0.01 mm. Laser triangulation and image matching were combined dexterously to adapt wings' complex shape, size, and transparency. It is suitable for insect flight research or flapping wing micro-air vehicle development.

Approches pour la reduction de l'impact de defaut dans le transport d'energie du parc eolien offshore via VSC-HVDC =

NASA Astrophysics Data System (ADS)

Benadja, Mounir

Dans ce travail est presente un systeme de generation d'energie d'un parc eolien offshore et un systeme de transport utilisant les stations VSC-HVDC connectees au reseau principal AC onshore. Trois configurations ont ete etudiees, modelisees et validees par simulation. Dans chacune des configurations, des contributions ameliorant les cotes techniques et economiques sont decrites ci-dessous : La premiere contribution concerne un nouvel algorithme MPPT (Maximum Power Point Tracking) utilise pour l'extraction de la puissance maximale disponible dans les eoliennes des parcs offshores. Cette technique d'extraction du MPPT ameliore le rendement energetique de la chaine de conversion des energies renouvelables notamment l'energie eolienne a petite et a grande echelles (parc eolien offshore) qui constitue un probleme pour les constructeurs qui se trouvent confrontes a developper des dispositifs MPPT simples, moins couteux, robustes, fiables et capable d'obtenir un rendement energetique maximal. La deuxieme contribution concerne la reduction de la taille, du cout et de l'impact des defauts electriques (AC et DC) dans le systeme construit pour transporter l'energie d'un parc eolien offshore (OWF) vers le reseau principal AC onshore via deux stations 3L-NPC VSCHVDC. La solution developpee utilise des observateurs non-lineaires bases sur le filtre de Kalman etendu (EKF). Ce filtre permet d'estimer la vitesse de rotation et la position du rotor de chacune des generatrices du parc eolien offshore et de la tension du bus DC de l'onduleur DC-AC offshore et des deux stations 3L-NPC-VSC-HVDC (offshore et onshore). De plus, ce developpement du filtre de Kalman etendu a permis de reduire l'impact des defauts AC et DC. Deux commandes ont ete utilisees, l'une (commande indirect dans le plan abc) avec EKF integre destinee pour controler le convertisseur DC-AC offshore et l'autre (commande d-q) avec EKF integre pour controler les convertisseurs des deux stations AC-DC et DC-AC tout en

Computing Fault Displacements from Surface Deformations

NASA Technical Reports Server (NTRS)

Lyzenga, Gregory; Parker, Jay; Donnellan, Andrea; Panero, Wendy

2006-01-01

Simplex is a computer program that calculates locations and displacements of subterranean faults from data on Earth-surface deformations. The calculation involves inversion of a forward model (given a point source representing a fault, a forward model calculates the surface deformations) for displacements, and strains caused by a fault located in isotropic, elastic half-space. The inversion involves the use of nonlinear, multiparameter estimation techniques. The input surface-deformation data can be in multiple formats, with absolute or differential positioning. The input data can be derived from multiple sources, including interferometric synthetic-aperture radar, the Global Positioning System, and strain meters. Parameters can be constrained or free. Estimates can be calculated for single or multiple faults. Estimates of parameters are accompanied by reports of their covariances and uncertainties. Simplex has been tested extensively against forward models and against other means of inverting geodetic data and seismic observations. This work

GPS-derived crustal deformation in Azerbaijan

NASA Astrophysics Data System (ADS)

Safarov, Rafig; Mammadov, Samir; Kadirov, Fakhraddin

2017-04-01

Crustal deformations of the Earth's crust in Azerbaijan were studied based on GPS measurements. The GPS velocity vectors for Azerbaijan, Iran, Georgia, and Armenia were used in order to estimate the deformation rates. It is found that compression is observable along the Greater Caucasus, in Gobustan, the Kura depression, Nakhchyvan Autonomous Republic, and adjacent areas of Iran. The axes of compression/contraction of the crust in the Greater Caucasus region are oriented in the S-NE direction. The maximum strain rate is observed in the zone of mud volcanism at the SHIK site (Shykhlar), which is marked by a sharp change in the direction of the compression axes (SW-NE). It is revealed that the deformation field also includes the zones where strain rates are very low. These zones include the Caspian-Guba and northern Gobustan areas, characterized by extensive development of mud volcanism. The extension zones are confined to the Lesser Caucasus and are revealed in the Gyadabei (GEDA) and Shusha (SHOU) areas. The analysis of GPS data for the territory of Azerbaijan and neighboring countries reveals the heterogeneous patterns of strain field in the region. This fact suggests that the block model is most adequate for describing the structure of the studied region. The increase in the number of GPS stations would promote increasing the degree of detail in the reconstructions of the deformation field and identifying the microplate boundaries.It is concluded that the predominant factor responsible for the eruption of mud volcanoes is the intensity of gasgeneration processes in the earth's interior, while deformation processes play the role of a trigger. The zone of the epicenters of strong earthquakes is correlated to the gradient zone in the crustal strain rates.

Analyses of Deformation and Stress of Oil-free Scroll Compressor Scroll

NASA Astrophysics Data System (ADS)

Peng, Bin; Li, Yaohong; Zhao, Shenxian

2017-12-01

The solid model of orbiting and fixed scroll is created by the Solidworks The deformation and stress of scrolls under gas force, temperature field, inertia force and the coupling field are analyzed using the Ansys software. The deformation for different thickness and height scroll tooth is investigated. The laws of deformation and stress for scrolls are gotten. The research results indicate that the stress and deformation of orbiting scroll are mainly affected by the temperature field. The maximum deformation occurs in the tooth head of scroll wrap because of the largest gas forces and the highest temperature in the tooth head of scroll wrap. The maximum stress is located in the end of the tooth, and the maximum stress of the coupling field is not the sum of loads. The scroll tooth is higher, and the deformation is bigger. The scroll tooth is thicker, and the deformation is smaller.

T\\overline{T} -deformations, AdS/CFT and correlation functions

NASA Astrophysics Data System (ADS)

Giribet, Gaston

2018-02-01

A solvable irrelevant deformation of AdS3/CFT2 correspondence leading to a theory with Hagedorn spectrum at high energy has been recently proposed. It consists of a single trace deformation of the boundary theory, which is inspired by the recent work on solvable T\\overline{T} deformations of two-dimensional CFTs. Thought of as a worldsheet σ-model, the interpretation of the deformed theory from the bulk viewpoint is that of string theory on a background that interpolates between AdS3 in the IR and a linear dilaton vacuum of little string theory in the UV. The insertion of the operator that realizes the deformation in the correlation functions produces a logarithmic divergence, leading to the renormalization of the primary operators, which thus acquire an anomalous dimension. We compute this anomalous dimension explicitly, and this provides us with a direct way of determining the spectrum of the theory. We discuss this and other features of the correlation functions in presence of the deformation.

How the continents deform: The evidence from tectonic geodesy

USGS Publications Warehouse

Thatcher, Wayne R.

2009-01-01

Space geodesy now provides quantitative maps of the surface velocity field within tectonically active regions, supplying constraints on the spatial distribution of deformation, the forces that drive it, and the brittle and ductile properties of continental lithosphere. Deformation is usefully described as relative motions among elastic blocks and is block-like because major faults are weaker than adjacent intact crust. Despite similarities, continental block kinematics differs from global plate tectonics: blocks are much smaller, typically ∼100–1000 km in size; departures from block rigidity are sometimes measurable; and blocks evolve over ∼1–10 Ma timescales, particularly near their often geometrically irregular boundaries. Quantitatively relating deformation to the forces that drive it requires simplifying assumptions about the strength distribution in the lithosphere. If brittle/elastic crust is strongest, interactions among blocks control the deformation. If ductile lithosphere is the stronger, its flow properties determine the surface deformation, and a continuum approach is preferable.

[Which foot deformities should be radiologist be familiar with?

PubMed

von Stillfried, E

2018-05-01

Most deformities of the foot are visible at birth and can be diagnosed without imaging. They can be divided into congenital flexible, congenital structural and acquired foot deformities. The most common congenital flexible foot deformity in children is the metatarsus adductus, which usually requires no long-term therapy. Regarding congenital structural deformities, such as the clubfoot and talus verticalis, plaster therapy should be started during the first week of life, so that by the end of the first year of life and the beginning of the verticalization, a pain-free resilient foot with normal function is present. Imaging is usually only necessary if a relapse arises. Coalitio of the tarsal bones is often visible only in the course of growth through the development of a rigid flatfoot and always requires imaging to confirm the diagnosis. This article is intended to give the radiologist an overview of the most important deformities and to inform about their course and therapy.

Dynamics of Deformable Active Particles under External Flow Field

NASA Astrophysics Data System (ADS)

Tarama, Mitsusuke

2017-10-01

In most practical situations, active particles are affected by their environment, for example, by a chemical concentration gradient, light intensity, gravity, or confinement. In particular, the effect of an external flow field is important for particles swimming in a solvent fluid. For deformable active particles such as self-propelled liquid droplets and active vesicles, as well as microorganisms such as euglenas and neutrophils, a general description has been developed by focusing on shape deformation. In this review, we present our recent studies concerning the dynamics of a single active deformable particle under an external flow field. First, a set of model equations of active deformable particles including the effect of a general external flow is introduced. Then, the dynamics under two specific flow profiles is discussed: a linear shear flow, as the simplest example, and a swirl flow. In the latter case, the scattering dynamics of the active deformable particles by the swirl flow is also considered.

Deformation behavior of TC6 alloy in isothermal forging

NASA Astrophysics Data System (ADS)

Li, Xiaoli; Li, Miaoquan; Zhu, Dasong; Xiong, Aiming

2005-10-01

Isothermal compression of the TC6 alloy was carried out in a Thermecmaster-Z (Wuhan Iron and Steel Corporation, P.R. China) simulator at deformation temperatures of 800˜1040 °C, strain rates of 0.001˜50.0 s-1, and maximum height reduction of 50%. The deformation behavior of the TC6 alloy in isothermal forging was characterized based on stress-strain behavior and kinetic analysis. The activation energy of deformation obtained in the isothermal forging of the TC6 alloy was 267.49 kJ/mol in the β phase region and 472.76 kJ/mol in the α+β phase region. The processing map was constructed based on the dynamic materials model, and the optimal deformation parameters were obtained. Constitutive equations describing the flow stress as a function of strain rate, strain, and deformation temperature were proposed for the isothermal forging of the TC6 alloy, and a good agreement between the predicted and experimental stress-strain curves was achieved.

Residual stresses and plastic deformation in GTA-welded steel

DOE Office of Scientific and Technical Information (OSTI.GOV)

Brand, P.C.; Keijser, T.H. de; Ouden, G. den

1993-03-01

Residual stresses and plastic deformation in single pass GTA welded low-carbon steel were studied by means of x-ray diffraction in combination with optical microscopy and hardness measurements. The residual stresses and the amount of plastic deformation (microstrain) were obtained from x-ray diffraction line positions and line broading. Since the plates were polished before welding, it was possible to observe in the optical microscope two types of Lueders bands. During heating curved Lueders bands and during cooling straight Lueders bands perpendicular to the weld are formed. The curved Lueders bands extend over a larger distance from the weld than the straightmore » Lueders bands. The amount of plastic deformation as obtained from the x-ray diffraction analysis is in agreement with these observations. An explanation is offered for the stresses measured in combination with plastic deformations observed. It is concluded that in the present experiments plastic deformation is the main cause of the residual stresses.« less

Tension-dependent structural deformation alters single-molecule transition kinetics.

PubMed

Sudhanshu, B; Mihardja, S; Koslover, E F; Mehraeen, S; Bustamante, C; Spakowitz, A J

2011-02-01

We analyze the response of a single nucleosome to tension, which serves as a prototypical biophysical measurement where tension-dependent deformation alters transition kinetics. We develop a statistical-mechanics model of a nucleosome as a wormlike chain bound to a spool, incorporating fluctuations in the number of bases bound, the spool orientation, and the conformations of the unbound polymer segments. With the resulting free-energy surface, we perform dynamic simulations that permit a direct comparison with experiments. This simple approach demonstrates that the experimentally observed structural states at nonzero tension are a consequence of the tension and that these tension-induced states cease to exist at zero tension. The transitions between states exhibit substantial deformation of the unbound polymer segments. The associated deformation energy increases with tension; thus, the application of tension alters the kinetics due to tension-induced deformation of the transition states. This mechanism would arise in any system where the tether molecule is deformed in the transition state under the influence of tension.

Deformation in the mantle wedge associated with Laramide flat-slab subduction and implications for surface deformation during the Laramide orogeny

NASA Astrophysics Data System (ADS)

Behr, W. M.; Smith, D.

2016-12-01

Laramide crustal deformation in the Rocky Mountains of the west-central United States is often considered to relate to a narrow segment of shallow subduction of the Farallon slab, but there is no consensus as to how deformation along the slab-mantle lithosphere interface was accommodated. Here we investigate deformation in mantle rocks associated with hydration and shear above the flat-slab at its contact with the base of the North American plate. The rocks we focus on are deformed, hydrated, ultramafic inclusions hosted within diatremes of the Navajo Volcanic Field in the central Colorado Plateau that erupted during the waning stages of the Laramide orogeny. We document a range of deformation textures, including granular peridotites, porphyroclastic peridotites, mylonites, and cataclasites, which we interpret to reflect different proximities to a slab-mantle-interface shear zone. Mineral assemblages and chemistries constrain deformation to hydrous conditions in the temperature range 550-750 C. Despite the presence of hydrous phyllosilicates in modal percentages of up to 30%, deformation was dominated by dislocation creep in olivine. The mylonites exhibit an uncommon lattice preferred orientation (LPO) in olivine, known as B-type LPO in which the a-axes are aligned perpendicular to the flow direction. The low temperature, hydrated setting in which these fabrics formed is consistent with laboratory experiments that indicate B-type LPOs form under conditions of high stress and high water contents; furthermore, the mantle wedge context of these LPOs is consistent with observations of trench-parallel anisotropy in the mantle wedge above many modern subduction zones. Differential stress magnitudes in the mylonitic rocks estimated using paleopiezometry range from 290 to 444 MPa, and calculated effective viscosities using a wet olivine flow law are on the order of 10^19 to 10^23 Pa s. The high stress magnitudes, high effective viscosities, and high strains recorded in

Gas Release as a Deformation Signal

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bauer, Stephen J.

Radiogenic noble gases are contained in crustal rock at inter and intra granular sites. The gas composition depends on lithology, geologic history, fluid phases, and the aging effect by decay of U, Th, and K. The isotopic signature of noble gases found in rocks is vastly different than that of the atmosphere which is contributed by a variety of sources. When rock is subjected to stress conditions exceeding about half its yield strength, micro-cracks begin to form. As rock deformation progresses a fracture network evolves, releasing trapped noble gases and changing the transport properties to gas migration. Thus, changes inmore » gas emanation and noble gas composition from rocks could be used to infer changes in stress-state and deformation. The purpose of this study has been to evaluate the effect of deformation/strain rate upon noble gas release. Four triaxial experiments were attempted for a strain rate range of %7E10-8 /s (180,000s) to %7E 10-4/s (500s); the three fully successful experiments (at the faster strain rates) imply the following: (1) helium is measurably released for all strain rates during deformation, this release is in amounts 1-2 orders of magnitude greater than that present in the air, and (2) helium gas release increases with decreasing strain rate.« less

Reconstruction d’une Carbonisation du Pouce par Lambeau Chinois

PubMed Central

Khales, A.; Achbouk, J.A.; Moussaoui, A.; Belmir, R.; Tourabi, K.; Oufkir, A.; Ihrai, H.

2010-01-01

Summary La main en tant qu’organe majeur de la préhension peut être le siège de brûlures graves qui compromettent sa fonction. Bien qu’elle ne représente que 2% de la surface corporelle la brûlure de la main est grave et difficile à traiter, vu la vulnérabilité et la complexité de son appareil locomoteur. Nous rapportons dans ce travail le cas d’un patient victime d’une carbonisation de la main. Huit mois après le parage et la couverture par lambeau inguinal, le patient bénéficie d’une reconstruction du pouce par lambeau chinois associé à une greffe osseuse. Le résultat s’est avéré satisfaisant. Le lambeau chinois prouve par son apport vasculaire et par sa facilité technique qu’il est un moyen très intéressant dans la reconstruction du pouce - ou des doigts en général - surtout dans un contexte de brûlure. PMID:21991226

Magnetic anisotropy and magnetite textures from experimental shear deformation

NASA Astrophysics Data System (ADS)

Till, Jessica; Moskowitz, Bruce

2015-04-01

Magnetite is a common accessory mineral in crustal rocks and exerts a dominant influence on the magnetic anisotropy of rocks when present. Therefore the deformation behavior of magnetite strongly determines how magnetic fabric develops with increasing strain in a deforming rock. Here we show results from experimental deformation of magnetite-silicate aggregates in high-temperature transpressional shear experiments (1000-1200°C) under moderate shear stresses (10-130 MPa) using a gas-medium deformation apparatus. Anisotropy of magnetic susceptibility, shape preferred orientation (SPO) of magnetite, and electron backscatter diffraction (EBSD) were each used to characterize the magnetite deformation fabrics and intragrain microstructures. Magnetic anisotropy and SPO each increase strongly with increasing strain, which ranged between 100-300%. An interesting feature of the deformation fabrics is that both magnetite SPO and magnetic fabric intensity are stronger at higher temperatures, indicating that strain partitioning between magnetite and the plagioclase matrix decreases at higher temperatures. Although flow laws for magnetite predict it to be weaker than dry plagioclase at the experimental conditions, the temperature-dependence of the fabric strength indicates that magnetite is more viscous than the "wet" plagioclase used in the experiments. In contrast to the magnetic and shape fabrics, crystallographic preferred orientation (CPO) of magnetite is very weak in all deformed samples. In EBSD orientation mapping of individual particles, incipient subgrain boundary formation is evident in magnetite grains, indicating that dislocation creep processes were active in magnetite despite the lack of a well-developed CPO. The weak magnetite CPOs are primarily attributed to multiple slip systems acting in parallel. These findings support the observations of previous studies that crystallographic textures in cubic minerals such as magnetite may be inherently weak or slow to

The Time-Dependency of Deformation in Porous Carbonate Rocks

NASA Astrophysics Data System (ADS)

Kibikas, W. M.; Lisabeth, H. P.; Zhu, W.

2016-12-01

Porous carbonate rocks are natural reservoirs for freshwater and hydrocarbons. More recently, due to their potential for geothermal energy generation as well as carbon sequestration, there are renewed interests in better understanding of the deformation behavior of carbonate rocks. We conducted a series of deformation experiments to investigate the effects of strain rate and pore fluid chemistry on rock strength and transport properties of porous limestones. Indiana limestone samples with initial porosity of 16% are deformed at 25 °C under effective pressures of 10, 30, and 50 MPa. Under nominally dry conditions, the limestone samples are deformed under 3 different strain rates, 1.5 x 10-4 s-1, 1.5 x 10-5 s-1 and 1.5 x 10-6 s-1 respectively. The experimental results indicate that the mechanical behavior is both rate- and pressure-dependent. At low confining pressures, post-yielding deformation changes from predominantly strain softening to strain hardening as strain rate decreases. At high confining pressures, while all samples exhibit shear-enhanced compaction, decreasing strain rate leads to an increase in compaction. Slower strain rates enhance compaction at all confining pressure conditions. The rate-dependence of deformation behaviors of porous carbonate rocks at dry conditions indicates there is a strong visco-elastic coupling for the degradation of elastic modulus with increasing plastic deformation. In fluid saturated samples, inelastic strain of limestone is partitioned among low temperature plasticity, cataclasis and solution transport. Comparison of inelastic behaviors of samples deformed with distilled water and CO2-saturated aqueous solution as pore fluids provide experimental constraints on the relative activities of the various mechanisms. Detailed microstructural analysis is conducted to take into account the links between stress, microstructure and the inelastic behavior and failure mechanisms.

Proprietes ionochromes et photochromes de derives du polythiophene

NASA Astrophysics Data System (ADS)

Levesque, Isabelle

La synthese et la caracterisation de derives regioreguliers du polythiophene ont ete effectuees en solution et sur des films minces. La spectroscopie UV-visible de ces derives a permis de constater qu'ils peuvent posseder des proprietes chromiques particulieres selon le stimulus auquel ils sont soumis. Par exemple, une augmentation de la temperature permet en effet aux polymeres de passer d'une couleur violette a jaune, et ce, a l'etat solide aussi bien qu'en solution. Ces proprietes chromiques semblent regies par une transition conformationnelle (plane a non-plane) de la chaine principale. Ce travail avait pour but de mieux comprendre l'influence de l'organisation des chaines laterales sur les transitions chromiques. Deux derives synthetises possedant des chaines laterales sensibles aux cations alcalins se sont averes etre ionochromes en plus d'etre thermochromes. Il s'agit d'un polymere comportant des chaines laterales de type oligo(oxyethylene) et d'un autre comportant un groupement ether couronne specifique aux ions lithium. Les effets chromiques observes sont expliques par des interactions non-covalentes des cations avec les atomes d'oxygene des chaines laterales dans le cas du premier polymere, et par l'insertion de l'ion Li + dans la cavite de l'ether couronne dans le cas du second polymere. Ces interactions semblent provoquer une diminution de l'organisation induisant ainsi une torsion de la chaine principale. Les deux polymeres semblent specifiques a certains cations et pourraient donc servir comme detecteurs optiques. La specificite aux ions Li+ du second polymere pourrait aussi permettre la conduction ionique, en plus de la conductivite electronique caracteristique des polythiophenes, ce qui pourrait s'averer utile dans le cas de batteries legeres entierement faites de polymeres et de sels de lithium. D'autres derives comportant des chaines laterales de type azobenzene se sont averes etre photochromes en plus d'etre thermochromes. Le groupement lateral a

TH-CD-206-08: An Anthropopathic Deformable Phantom for Geometric and Dose Accumulation Accuracy Validation of Deformable Image Registration

DOE Office of Scientific and Technical Information (OSTI.GOV)

Liao, Y; Chen, H; Chen, J

2016-06-15

Purpose: To design and construct a three-dimensional (3D) anthropopathic abdominal phantom for evaluating deformable image registration (DIR) accuracy on images and dose deformation in adaptive radiation therapy (ART). Method: Organ moulds, including liver, kidney, spleen, stomach, vertebra and two metastasis tumors, are 3D printed using the contours from an ovarian cancer patient. The organ moulds are molded with deformable gels that made of different mixtures of polyvinyl chloride (PVC) and the softener dioctyl terephthalate. Gels with different densities are obtained by a polynomial fitting curve which describes the relation between the CT number and PVC-softener blending ratio. The rigid vertebrasmore » are constructed by moulding with white cement. The final abdominal phantom is assembled by arranging all the fabricated organs inside a hollow dummy according to their anatomies and sealed with deformable gel with averaged CT number of muscle and fat. Geometric and dosimetric landmarks are embedded inside the phantom for spatial accuracy and dose accumulation accuracy studies. Three DIR algorithms available in the open source DIR toolkit-DIRART, including the Demons, the Horn-Schunck and Lucas-Kanade method and the Level-Set Motion method, are tested using the constructed phantom. Results: Viscoelastic behavior is observed in the constructed deformable gel, which serves as an ideal material for the deformable phantom. The constructed abdominal phantom consists of highly realistic anatomy and the fabricated organs inside have close CT number to its reference patient. DIR accuracy studies conducted on the constructed phantom using three DIR approaches indicate that geometric accuracy of a DIR algorithm has achieved does not guarantee accuracy in dose accumulation. Conclusions: We have designed and constructed an anthropopathic abdominal deformable phantom with satisfactory elastic property, realistic organ density and anatomy. This physical phantom is recyclable

Fluctuating Nonlinear Spring Model of Mechanical Deformation of Biological Particles

PubMed Central

Kononova, Olga; Snijder, Joost; Kholodov, Yaroslav; Marx, Kenneth A.; Wuite, Gijs J. L.; Roos, Wouter H.; Barsegov, Valeri

2016-01-01

The mechanical properties of virus capsids correlate with local conformational dynamics in the capsid structure. They also reflect the required stability needed to withstand high internal pressures generated upon genome loading and contribute to the success of important events in viral infectivity, such as capsid maturation, genome uncoating and receptor binding. The mechanical properties of biological nanoparticles are often determined from monitoring their dynamic deformations in Atomic Force Microscopy nanoindentation experiments; but a comprehensive theory describing the full range of observed deformation behaviors has not previously been described. We present a new theory for modeling dynamic deformations of biological nanoparticles, which considers the non-linear Hertzian deformation, resulting from an indenter-particle physical contact, and the bending of curved elements (beams) modeling the particle structure. The beams’ deformation beyond the critical point triggers a dynamic transition of the particle to the collapsed state. This extreme event is accompanied by a catastrophic force drop as observed in the experimental or simulated force (F)-deformation (X) spectra. The theory interprets fine features of the spectra, including the nonlinear components of the FX-curves, in terms of the Young’s moduli for Hertzian and bending deformations, and the structural damage dependent beams’ survival probability, in terms of the maximum strength and the cooperativity parameter. The theory is exemplified by successfully describing the deformation dynamics of natural nanoparticles through comparing theoretical curves with experimental force-deformation spectra for several virus particles. This approach provides a comprehensive description of the dynamic structural transitions in biological and artificial nanoparticles, which is essential for their optimal use in nanotechnology and nanomedicine applications. PMID:26821264

DuOCam: A Two-Channel Camera for Simultaneous Photometric Observations of Stellar Clusters

NASA Astrophysics Data System (ADS)

Maier, Erin R.; Witt, Emily; Depoy, Darren L.; Schmidt, Luke M.

2017-01-01

We have designed the Dual Observation Camera (DuOCam), which uses commercial, off-the-shelf optics to perform simultaneous photometric observations of astronomical objects at red and blue wavelengths. Collected light enters DuOCam’s optical assembly, where it is collimated by a negative doublet lens. It is then separated by a 45 degree blue dichroic filter (transmission bandpass: 530 - 800 nm, reflection bandpass: 400 - 475 nm). Finally, the separated light is focused by two identical positive doublet lenses onto two independent charge-coupled devices (CCDs), the SBIG ST-8300M and the SBIG STF-8300M. This optical assembly converts the observing telescope to an f/11 system, which balances maximum field of view with optimum focus. DuOCam was commissioned on the McDonald Observatory 0.9m, f/13.5 telescope from July 21st - 24th, 2016. Observations of three globular and three open stellar clusters were carried out. The resulting data were used to construct R vs. B-R color magnitude diagrams for a selection of the observed clusters. The diagrams display the characteristic evolutionary track for a stellar cluster, including the main sequence and main sequence turn-off.

Developpement d'une methode de Monte Carlo dependante du temps et application au reacteur de type CANDU-6

NASA Astrophysics Data System (ADS)

Mahjoub, Mehdi

La resolution de l'equation de Boltzmann demeure une etape importante dans la prediction du comportement d'un reacteur nucleaire. Malheureusement, la resolution de cette equation presente toujours un defi pour une geometrie complexe (reacteur) tout comme pour une geometrie simple (cellule). Ainsi, pour predire le comportement d'un reacteur nucleaire,un schema de calcul a deux etapes est necessaire. La premiere etape consiste a obtenir les parametres nucleaires d'une cellule du reacteur apres une etape d'homogeneisation et condensation. La deuxieme etape consiste en un calcul de diffusion pour tout le reacteur en utilisant les resultats de la premiere etape tout en simplifiant la geometrie du reacteur a un ensemble de cellules homogenes le tout entoure de reflecteur. Lors des transitoires (accident), ces deux etapes sont insuffisantes pour pouvoir predire le comportement du reacteur. Comme la resolution de l'equation de Boltzmann dans sa forme dependante du temps presente toujours un defi de taille pour tous types de geometries,un autre schema de calcul est necessaire. Afin de contourner cette difficulte, l'hypothese adiabatique est utilisee. Elle se concretise en un schema de calcul a quatre etapes. La premiere et deuxieme etapes demeurent les memes pour des conditions nominales du reacteur. La troisieme etape se resume a obtenir les nouvelles proprietes nucleaires de la cellule a la suite de la perturbation pour les utiliser, au niveau de la quatrieme etape, dans un nouveau calcul de reacteur et obtenir l'effet de la perturbation sur le reacteur. Ce projet vise a verifier cette hypothese. Ainsi, un nouveau schema de calcul a ete defini. La premiere etape de ce projet a ete de creer un nouveau logiciel capable de resoudre l'equation de Boltzmann dependante du temps par la methode stochastique Monte Carlo dans le but d'obtenir des sections efficaces qui evoluent dans le temps. Ce code a ete utilise pour simuler un accident LOCA dans un reacteur nucleaire de type

Correction of Stahl ear deformity using a suture technique.

PubMed

Khan, Muhammad Adil Abbas; Jose, Rajive M; Ali, Syed Nadir; Yap, Lok Huei

2010-09-01

Correction of partial ear deformities can be a challenging task for the plastic surgeon. There are no standard techniques for correcting many of these deformities, and several different techniques are described in literature. Stahl ear is one such anomaly, characterized by an accessory third crus in the ear cartilage, giving rise to an irregular helical rim. The conventional techniques of correcting this deformity include either excision of the cartilage, repositioning of the cartilage, or scoring techniques. We recently encountered a case of Stahl ear deformity and undertook correction using internal sutures with very good results. The technical details of the surgery are described along with a review of literature on correcting similar anomalies.

Sensing surface mechanical deformation using active probes driven by motor proteins

PubMed Central

Inoue, Daisuke; Nitta, Takahiro; Kabir, Arif Md. Rashedul; Sada, Kazuki; Gong, Jian Ping; Konagaya, Akihiko; Kakugo, Akira

2016-01-01

Studying mechanical deformation at the surface of soft materials has been challenging due to the difficulty in separating surface deformation from the bulk elasticity of the materials. Here, we introduce a new approach for studying the surface mechanical deformation of a soft material by utilizing a large number of self-propelled microprobes driven by motor proteins on the surface of the material. Information about the surface mechanical deformation of the soft material is obtained through changes in mobility of the microprobes wandering across the surface of the soft material. The active microprobes respond to mechanical deformation of the surface and readily change their velocity and direction depending on the extent and mode of surface deformation. This highly parallel and reliable method of sensing mechanical deformation at the surface of soft materials is expected to find applications that explore surface mechanics of soft materials and consequently would greatly benefit the surface science. PMID:27694937

Supermultiplet of β-deformations from twistors

NASA Astrophysics Data System (ADS)

Milián, Segundo P.

2017-09-01

We consider the supermultiplet of linearized beta-deformation of 𝒩 = 4 super-Yang-Mills (SYM). It was previously studied on the gravitational side. We study the supermultiplet of beta-deformations on the field theory side and we compare two finite-dimensional representations of psl(4|4,R) algebra. We show that they are related by an intertwining operator. We develop a twistor-based approach which could be useful for studying other finite-dimensional and nonunitary representations in AdS/CFT correspondence.

Paleozoic and Mesozoic deformations in the central Sierra Nevada, California

USGS Publications Warehouse

Nokleberg, Warren J.; Kistler, Ronald Wayne

1980-01-01

Analysis of structural and stratigraphic data indicates that several periods of regional deformation, consisting of combined folding, faulting, cataclasis, and regional metamorphism, occurred throughout the central Sierra Nevada during Paleozoic and Mesozoic time. The oldest regional deformation occurred alono northward trends during the Devonian and Mississippian periods in most roof pendants containing lower Paleozoic metasedimentary rocks at the center and along the crest of the range. This deformation is expressed in some roof pendants by an angular unconformity separating older thrice-deformed from younger twice-deformed Paleozoic metasedimentary rocks. The first Mesozoic deformation, which consisted of uplift and erosion and was accompanied by the onset of Andean-type volcanism during the Permian and Triassic, is expressed by an angular unconformity in several roof pendants from the Saddlebag Lake to the Mount Morrison areas. This unconformity is defined by Permian and Triassic andesitic to rhyolitic metavolcanic rocks unconformably overlying more intensely deformed Pennsylvanian, Permian(?), and older metasedimentary rocks. A later regional deformation occurred during the Triassic along N. 20?_30? W. trends in Permian and Triassic metavolcanic rocks of the Saddlebag Lake and Mount Dana roof pendants, in upper Paleozoic rocks of the Pine Creek roof pendant, and in the Calaveras Formation of the western metamorphic belt; the roof pendants are crosscut by Upper Triassic granitic rocks of the Lee Vining intrusive epoch. A still later period of Early and Middle Jurassic regional deformation occurred along N. 30?-60? E. trends in upper Paleozoic rocks of the Calaveras Formation of the western metamorphic belt. A further period of deformation was the Late Jurassic Nevadan orogeny, which occurred along N. 20?_40? W. trends in Upper Jurassic rocks of the western metamorphic belt that are crosscut by Upper Jurassic granitic rocks of the Yosemite intrusive epoch

Elaboration du Ge mesoporeux et etude de ses proprietes physico-chimiques en vue d'applications photovoltaiques

NASA Astrophysics Data System (ADS)

Tutashkonko, Sergii

Le sujet de cette these porte sur l'elaboration du nouveau nanomateriau par la gravure electrochimique bipolaire (BEE) --- le Ge mesoporeux et sur l'analyse de ses proprietes physico-chimiques en vue de son utilisation dans des applications photovoltaiques. La formation du Ge mesoporeux par gravure electrochimique a ete precedemment rapportee dans la litterature. Cependant, le verrou technologique important des procedes de fabrication existants consistait a obtenir des couches epaisses (superieure a 500 nm) du Ge mesoporeux a la morphologie parfaitement controlee. En effet, la caracterisation physico-chimique des couches minces est beaucoup plus compliquee et le nombre de leurs applications possibles est fortement limite. Nous avons developpe un modele electrochimique qui decrit les mecanismes principaux de formation des pores ce qui nous a permis de realiser des structures epaisses du Ge mesoporeux (jusqu'au 10 mum) ayant la porosite ajustable dans une large gamme de 15% a 60%. En plus, la formation des nanostructures poreuses aux morphologies variables et bien controlees est desormais devenue possible. Enfin, la maitrise de tous ces parametres a ouvert la voie extremement prometteuse vers la realisation des structures poreuses a multi-couches a base de Ge pour des nombreuses applications innovantes et multidisciplinaires grace a la flexibilite technologique actuelle atteinte. En particulier, dans le cadre de cette these, les couches du Ge mesoporeux ont ete optimisees dans le but de realiser le procede de transfert de couches minces d'une cellule solaire a triple jonctions via une couche sacrificielle en Ge poreux. Mots-cles : Germanium meso-poreux, Gravure electrochimique bipolaire, Electrochimie des semi-conducteurs, Report des couches minces, Cellule photovoltaique

Crystallization of Deformable Spherical Colloids

NASA Astrophysics Data System (ADS)

Batista, Vera M. O.; Miller, Mark A.

2010-08-01

We introduce and characterize a first-order model for a generic class of colloidal particles that have a preferred spherical shape but can undergo deformations while always maintaining hard-body interactions. The model consists of hard spheres that can continuously change shape at fixed volume into prolate or oblate ellipsoids of revolution, subject to an energetic penalty. The severity of this penalty is specified by a single parameter that determines the flexibility of the particles. The deformable hard spheres crystallize at higher packing fractions than rigid hard spheres, have a narrower solid-fluid coexistence region and can reach high densities by a second transition to an orientationally ordered crystal.

Deforming baryons into confining strings

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hartnoll, Sean A.; Portugues, Ruben

2004-09-15

We find explicit probe D3-brane solutions in the infrared of the Maldacena-Nunez background. The solutions describe deformed baryon vertices: q external quarks are separated in spacetime from the remaining N-q. As the separation is taken to infinity we recover known solutions describing infinite confining strings in N=1 gauge theory. We present results for the mass of finite confining strings as a function of length. We also find probe D2-brane solutions in a confining type IIA geometry, the reduction of a G{sub 2} holonomy M theory background. The relation between these deformed baryons and confining strings is not as straightforward.

Atomistic Origin of Deformation Twinning in Biomineral Aragonite.

PubMed

Liu, Jialin; Huang, Zaiwang; Pan, Zhiliang; Wei, Qiuming; Li, Xiaodong; Qi, Yue

2017-03-10

Deformation twinning rarely occurs in mineral materials which typically show brittle fracture. Surprisingly, it has recently been observed in the biomineral aragonite phase in nacre under high rate impact loading. In this Letter, the twinning tendency and the competition between fracture and deformation twinning were revealed by first principles calculations. The ratio of the unstable stacking fault energy and the stacking fault energy in orthorhombic aragonite is hitherto the highest in a broad range of metallic and oxide materials. The underlining physics for this high ratio is the multineighbor shared ionic bonds and the unique relaxation process during sliding in the aragonite structure. Overall, the unique deformation twining along with other highly coordinated deformation mechanisms synergistically work in the hierarchical structure of nacre, leading to the remarkable strengthening and toughening of nacre upon dynamic loading, and thus protecting the mother-of-pearl from predatory attacks.

Angular Deformities of the Lower Limb in Children

PubMed Central

Espandar, Ramin; Mortazavi, Seyed Mohammad-Javad; Baghdadi, Taghi

2010-01-01

Angular deformities of the lower limbs are common during childhood. In most cases this represents a variation in the normal growth pattern and is an entirely benign condition. Presence of symmetrical deformities and absence of symptoms, joint stiffness, systemic disorders or syndromes indicates a benign condition with excellent long-term outcome. In contrast, deformities which are asymmetrical and associated with pain, joint stiffness, systemic disorders or syndromes may indicate a serious underlying cause and require treatment. Little is known about the relationship between sport participation and body adaptations during growth. Intense soccer participation increases the degree of genu varum in males from the age of 16. Since, according to some investigations, genu varum predisposes individuals to more injuries, efforts to reduce the development of genu varum in soccer players are warranted. In this article major topics of angular deformities of the knees in pediatric population are practically reviewed. PMID:22375192

Case studies of spinal deformities in ornamental koi, Cyprinus carpio L.

PubMed

Chin, H N; Loh, R; Hong, Y C; Gibson-Kueh, S

2017-01-01

This is a study of vertebral deformities in ornamental koi based on computed radiography and skeletons cleaned by dermestid beetles (Dermestes maculatus). All koi developed gradual onset of swimming abnormalities as adults. Extensive intervertebral osteophyte formation correlated with age of fish and was associated with hindquarter paresis in one koi. Vertebral compression and fusion were the most common spinal deformities occurring at multiple sites, similar to findings in other farmed fish. Site-specific spinal deformities were thought to develop due to differences in swimming behaviour and rates of vertebral growth. One koi had offspring with spinal deformities. Spinal deformities are significant problems in both European and Australian food fish hatcheries. The heritability of vertebral deformities in farmed fish is reportedly low unless there is concurrent poor husbandry or nutritional deficiencies. The specific aetiologies for vertebral deformities in koi in this study could not be ascertained. Current knowledge on spinal deformities in the better studied European food fish species suggests multifactorial aetiologies. Future research should include prospective longitudinal studies of larger numbers of koi from hatch and consideration of all potential risk factors such as husbandry, nutrition, temperature, photoperiod and genetics. © 2016 John Wiley & Sons Ltd.

Deformation field correction for spatial normalization of PET images

PubMed Central

Bilgel, Murat; Carass, Aaron; Resnick, Susan M.; Wong, Dean F.; Prince, Jerry L.

2015-01-01

Spatial normalization of positron emission tomography (PET) images is essential for population studies, yet the current state of the art in PET-to-PET registration is limited to the application of conventional deformable registration methods that were developed for structural images. A method is presented for the spatial normalization of PET images that improves their anatomical alignment over the state of the art. The approach works by correcting the deformable registration result using a model that is learned from training data having both PET and structural images. In particular, viewing the structural registration of training data as ground truth, correction factors are learned by using a generalized ridge regression at each voxel given the PET intensities and voxel locations in a population-based PET template. The trained model can then be used to obtain more accurate registration of PET images to the PET template without the use of a structural image. A cross validation evaluation on 79 subjects shows that the proposed method yields more accurate alignment of the PET images compared to deformable PET-to-PET registration as revealed by 1) a visual examination of the deformed images, 2) a smaller error in the deformation fields, and 3) a greater overlap of the deformed anatomical labels with ground truth segmentations. PMID:26142272

Tunable deformation modes shape contractility in active biopolymer networks

NASA Astrophysics Data System (ADS)

Stam, Samantha; Banerjee, Shiladitya; Weirich, Kim; Freedman, Simon; Dinner, Aaron; Gardel, Margaret

Biological polymer-based materials remodel under active, molecular motor-driven forces to perform diverse physiological roles, such as force transmission and spatial self-organization. Critical to understanding these biomaterials is elucidating the role of microscopic polymer deformations, such as stretching, bending, buckling, and relative sliding, on material remodeling. Here, we report that the shape of motor-driven deformations can be used to identify microscopic deformation modes and determine how they propagate to longer length scales. In cross-linked actin networks with sufficiently low densities of the motor protein myosin II, microscopic network deformations are predominantly uniaxial, or dominated by sliding. However, longer-wavelength modes are mostly biaxial, or dominated by bending and buckling, indicating that deformations with uniaxial shapes do not propagate across length scales significantly larger than that of individual polymers. As the density of myosin II is increased, biaxial modes dominate on all length scales we examine due to buildup of sufficient stress to produce smaller-wavelength buckling. In contrast, when we construct networks from unipolar, rigid actin bundles, we observe uniaxial, sliding-based contractions on 1 to 100 μm length scales. Our results demonstrate the biopolymer mechanics can be used to tune deformation modes which, in turn, control shape changes in active materials.

Insights into asthenospheric anisotropy and deformation in Mainland China

NASA Astrophysics Data System (ADS)

Zhu, Tao

2018-03-01

Seismic anisotropy can provide direct constraints on asthenospheric deformation which also can be induced by the inherent mantle flow within our planet. Mantle flow calculations thus have been an effective tool to probe asthenospheric anisotropy. To explore the source of seismic anisotropy, asthenospheric deformation and the effects of mantle flow on seismic anisotropy in Mainland China, mantle flow models driven by plate motion (plate-driven) and by a combination of plate motion and mantle density heterogeneity (plate-density-driven) are used to predict the fast polarization direction of shear wave splitting. Our results indicate that: (1) plate-driven or plate-density-driven mantle flow significantly affects the predicted fast polarization direction when compared with simple asthenospheric flow commonly used in interpreting the asthenospheric source of seismic anisotropy, and thus new insights are presented; (2) plate-driven flow controls the fast polarization direction while thermal mantle flow affects asthenospheric deformation rate and local deformation direction significantly; (3) asthenospheric flow is an assignable contributor to seismic anisotropy, and the asthenosphere is undergoing low, large or moderate shear deformation controlled by the strain model, the flow plane/flow direction model or both in most regions of central and eastern China; and (4) the asthenosphere is under more rapid extension deformation in eastern China than in western China.

Creep deformation mechanism mapping in nickel base disk superalloys

DOE PAGES

Smith, Timothy M.; Unocic, Raymond R.; Deutchman, Hallee; ...

2016-05-10

We investigated the creep deformation mechanisms at intermediate temperature in ME3, a modern Ni-based disk superalloy, using diffraction contrast imaging. Both conventional transmission electron microscopy (TEM) and scanning TEM were utilised. Distinctly different deformation mechanisms become operative during creep at temperatures between 677-815 °C and at stresses ranging from 274 to 724 MPa. Both polycrystalline and single-crystal creep tests were conducted. The single-crystal tests provide new insight into grain orientation effects on creep response and deformation mechanisms. Creep at lower temperatures (≤760 °C) resulted in the thermally activated shearing modes such as microtwinning, stacking fault ribbons and isolated superlattice extrinsicmore » stacking faults. In contrast, these faulting modes occurred much less frequently during creep at 815 °C under lower applied stresses. Instead, the principal deformation mode was dislocation climb bypass. In addition to the difference in creep behaviour and creep deformation mechanisms as a function of stress and temperature, it was also observed that microstructural evolution occurs during creep at 760 °C and above, where the secondary coarsened and the tertiary precipitates dissolved. Based on this work, a creep deformation mechanism map is proposed, emphasising the influence of stress and temperature on the underlying creep mechanisms.« less

Deformations, moduli stabilisation and gauge couplings at one-loop

NASA Astrophysics Data System (ADS)

Honecker, Gabriele; Koltermann, Isabel; Staessens, Wieland

2017-04-01

We investigate deformations of Z_2 orbifold singularities on the toroidal orbifold {T}^6/(Z_2× Z_6) with discrete torsion in the framework of Type IIA orientifold model building with intersecting D6-branes wrapping special Lagrangian cycles. To this aim, we employ the hypersurface formalism developed previously for the orbifold {T}^6/(Z_2× Z_6) with discrete torsion and adapt it to the (Z_2× Z_6× Ω R) point group by modding out the remaining Z_3 subsymmetry and the orientifold projection Ω R. We first study the local behaviour of the Z_3× Ω R invariant deformation orbits under non-zero deformation and then develop methods to assess the deformation effects on the fractional three-cycle volumes globally. We confirm that D6-branes supporting USp(2 N) or SO(2 N) gauge groups do not constrain any deformation, while deformation parameters associated to cycles wrapped by D6-branes with U( N) gauge groups are constrained by D-term supersymmetry breaking. These features are exposed in global prototype MSSM, Left-Right symmetric and Pati-Salam models first constructed in [1, 2], for which we here count the number of stabilised moduli and study flat directions changing the values of some gauge couplings.

High Resolution, Large Deformation 3D Traction Force Microscopy

PubMed Central

López-Fagundo, Cristina; Reichner, Jonathan; Hoffman-Kim, Diane; Franck, Christian

2014-01-01

Traction Force Microscopy (TFM) is a powerful approach for quantifying cell-material interactions that over the last two decades has contributed significantly to our understanding of cellular mechanosensing and mechanotransduction. In addition, recent advances in three-dimensional (3D) imaging and traction force analysis (3D TFM) have highlighted the significance of the third dimension in influencing various cellular processes. Yet irrespective of dimensionality, almost all TFM approaches have relied on a linear elastic theory framework to calculate cell surface tractions. Here we present a new high resolution 3D TFM algorithm which utilizes a large deformation formulation to quantify cellular displacement fields with unprecedented resolution. The results feature some of the first experimental evidence that cells are indeed capable of exerting large material deformations, which require the formulation of a new theoretical TFM framework to accurately calculate the traction forces. Based on our previous 3D TFM technique, we reformulate our approach to accurately account for large material deformation and quantitatively contrast and compare both linear and large deformation frameworks as a function of the applied cell deformation. Particular attention is paid in estimating the accuracy penalty associated with utilizing a traditional linear elastic approach in the presence of large deformation gradients. PMID:24740435

Effects of nitric oxide on red blood cell deformability.

PubMed

Bor-Kucukatay, Melek; Wenby, Rosalinda B; Meiselman, Herbert J; Baskurt, Oguz K

2003-05-01

In addition to its known action on vascular smooth muscle, nitric oxide (NO) has been suggested to have cardiovascular effects via regulation of red blood cell (RBC) deformability. The present study was designed to further explore this possibility. Human RBCs in autologous plasma were incubated for 1 h with NO synthase (NOS) inhibitors [N(omega)-nitro-l-arginine methyl ester (l-NAME) and S-methylisothiourea], NO donors [sodium nitroprusside (SNP) and diethylenetriamine (DETA)-NONOate], an NO precursor (l-arginine), soluble guanylate cyclase inhibitors (1H-[1,2,4]oxadiazolo-[4,3-a]quinoxalin-1-one and methylene blue), and a potassium channel blocker [triethylammonium (TEA)]. After incubation, RBC deformability at various shear stresses was determined by ektacytometry. Both NOS inhibitors significantly reduced RBC deformability above a threshold concentration, whereas the NO donors increased deformability at optimal concentrations. NO donors, as well as the NO precursor l-arginine and the potassium blocker TEA, were able to reverse the effects of NOS inhibitors. Guanylate cyclase inhibition reduced RBC deformation, with both SNP and DETA-NONOate able to reverse this effect. These results thus indicate the importance of NO as a determinant of RBC mechanical behavior and suggest its regulatory role for normal RBC deformability.

Two Back Stress Hardening Models in Rate Independent Rigid Plastic Deformation

NASA Astrophysics Data System (ADS)

Yun, Su-Jin

In the present work, the constitutive relations based on the combination of two back stresses are developed using the Armstrong-Frederick, Phillips and Ziegler’s type hardening rules. Various evolutions of the kinematic hardening parameter can be obtained by means of a simple combination of back stress rate using the rule of mixtures. Thus, a wide range of plastic deformation behavior can be depicted depending on the dominant back stress evolution. The ultimate back stress is also determined for the present combined kinematic hardening models. Since a kinematic hardening rule is assumed in the finite deformation regime, the stress rate is co-rotated with respect to the spin of substructure obtained by incorporating the plastic spin concept. A comparison of the various co-rotational rates is also included. Assuming rigid plasticity, the continuum body consists of the elastic deformation zone and the plastic deformation zone to form a hybrid finite element formulation. Then, the plastic deformation behavior is investigated under various loading conditions with an assumption of the J2 deformation theory. The plastic deformation localization turns out to be strongly dependent on the description of back stress evolution and its associated hardening parameters. The analysis for the shear deformation with fixed boundaries is carried out to examine the deformation localization behavior and the evolution of state variables.

Deformation and thermal histories of ordinary chondrites: Evidence for post-deformation annealing and syn-metamorphic shock

NASA Astrophysics Data System (ADS)

Ruzicka, Alex; Hugo, Richard; Hutson, Melinda

2015-08-01

We show that olivine microstructures in seven metamorphosed ordinary chondrites of different groups studied with optical and transmission electron microscopy can be used to evaluate the post-deformation cooling setting of the meteorites, and to discriminate between collisions affecting cold and warm parent bodies. The L6 chondrites Park (shock stage S1), Bruderheim (S4), Leedey (S4), and Morrow County (S5) were affected by variable shock deformation followed by relatively rapid cooling, and probably cooled as fragments liberated by impact in near-surface settings. In contrast, Kernouvé (H6 S1), Portales Valley (H6/7 S1), and MIL 99301 (LL6 S1) appear to have cooled slowly after shock, probably by deep burial in warm materials. In these chondrites, post-deformation annealing lowered apparent optical strain levels in olivine. Additionally, Kernouvé, Morrow County, Park, MIL 99301, and possibly Portales Valley, show evidence for having been deformed at an elevated temperature (⩾800-1000 °C). The high temperatures for Morrow County can be explained by dynamic heating during intense shock, but Kernouvé, Park, and MIL 99301 were probably shocked while the H, L and LL parent bodies were warm, during early, endogenically-driven thermal metamorphism. Thus, whereas the S4 and S5 chondrites experienced purely shock-induced heating and cooling, all the S1 chondrites examined show evidence for static heating consistent with either syn-metamorphic shock (Kernouvé, MIL 99301, Park), post-deformation burial in warm materials (Kernouvé, MIL 99301, Portales Valley), or both. The results show the pitfalls in relying on optical shock classification alone to infer an absence of shock and to construct cooling stratigraphy models for parent bodies. Moreover, they provide support for the idea that "secondary" metamorphic and "tertiary" shock processes overlapped in time shortly after the accretion of chondritic planetesimals, and that impacts into warm asteroidal bodies were

Study of the Micro-Nonuniformity of the Plastic Deformation of Steel

NASA Technical Reports Server (NTRS)

Chechulin, B. B.

1957-01-01

The plastic flow during deformation of real polycrystalline metals has specific characteristics which distinguish the plastic deformation of metals from the deformation of ordinary isotropic bodies. One of these characteristics is the marked micro-nonuniformity of the plastic deformation of metals. P.O. Pashkov demonstrated the presence of a considerable micro-nonuniformity of the plastic deformation of coarse-grained steel wit medium or low carbon content. Analogous results in the case of tension of coarse-grained aluminum were obtained by W. Boas, who paid particular attention to the role of the grain boundaries in plastic flow. The nonuniformit of the plastic deformation in microvolumes was also recorded by T.N. Gudkova and others, on the alloy KhN80T. N.F. Lashko pointed out the nonuniformity of the plastic deformation for a series of pure polycrystalline metals and one-phase alloys. In his later reports, P.O. Pashkov arrives at he conclusion that the nonuniformity of the distribution of the deformation along the individual grains has a significant effect on the strength and plastic characteristics of polycrystalline metals in the process of plastic flow. However, until now there has not existed any systematic investigation of the general rules of the microscopic nonuniformit of plastic deformation even though the real polycrystalline metals are extremely simple with regard to structure. In the present report, an attempt is made to study the micrononuniformity of the flow of polycrystalline metals by the method of statistical analysis of the variation of the frequency diagrams of the nonuniformity of the grains in the process of plastic deformation.

Pourfour du Petit Syndrome Associated With Right Eye Pressure.

PubMed

Evans, Randolph W; Garibay, Adam; Foroozan, Rod

2017-06-01

Pourfour du Petit (PDP) syndrome is a rare disorder characterized by ipsilateral mydriasis, eyelid retraction, and hemifacial hyperhidrosis caused by hyperactivity of the ipsilateral oculosympathetic pathway. A case is presented of PDP syndrome associated with likely ipsilateral occipital neuralgia. We review the causes and co-morbidities and the clinical features of PDP. © 2017 American Headache Society.

Measuring skewness of red blood cell deformability distribution by laser ektacytometry

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nikitin, S Yu; Priezzhev, A V; Lugovtsov, A E

An algorithm is proposed for measuring the parameters of red blood cell deformability distribution based on laser diffractometry of red blood cells in shear flow (ektacytometry). The algorithm is tested on specially prepared samples of rat blood. In these experiments we succeeded in measuring the mean deformability, deformability variance and skewness of red blood cell deformability distribution with errors of 10%, 15% and 35%, respectively. (laser biophotonics)

Predicting translational deformity following opening-wedge osteotomy for lower limb realignment.

PubMed

Barksfield, Richard C; Monsell, Fergal P

2015-11-01

An opening-wedge osteotomy is well recognised for the management of limb deformity and requires an understanding of the principles of geometry. Translation at the osteotomy is needed when the osteotomy is performed away from the centre of rotation of angulation (CORA), but the amount of translation varies with the distance from the CORA. This translation enables proximal and distal axes on either side of the proposed osteotomy to realign. We have developed two experimental models to establish whether the amount of translation required (based on the translation deformity created) can be predicted based upon simple trigonometry. A predictive algorithm was derived where translational deformity was predicted as 2(tan α × d), where α represents 50 % of the desired angular correction, and d is the distance of the desired osteotomy site from the CORA. A simulated model was developed using TraumaCad online digital software suite (Brainlab AG, Germany). Osteotomies were simulated in the distal femur, proximal tibia and distal tibia for nine sets of lower limb scanograms at incremental distances from the CORA and the resulting translational deformity recorded. There was strong correlation between the distance of the osteotomy from the CORA and simulated translation deformity for distal femoral deformities (correlation coefficient 0.99, p < 0.0001), proximal tibial deformities (correlation coefficient 0.93-0.99, p < 0.0001) and distal tibial deformities (correlation coefficient 0.99, p < 0.0001). There was excellent agreement between the predictive algorithm and simulated translational deformity for all nine simulations (correlation coefficient 0.93-0.99, p < 0.0001). Translational deformity following corrective osteotomy for lower limb deformity can be anticipated and predicted based upon the angular correction and the distance between the planned osteotomy site and the CORA.

Variable-intercept panel model for deformation zoning of a super-high arch dam.

PubMed

Shi, Zhongwen; Gu, Chongshi; Qin, Dong

2016-01-01

This study determines dam deformation similarity indexes based on an analysis of deformation zoning features and panel data clustering theory, with comprehensive consideration to the actual deformation law of super-high arch dams and the spatial-temporal features of dam deformation. Measurement methods of these indexes are studied. Based on the established deformation similarity criteria, the principle used to determine the number of dam deformation zones is constructed through entropy weight method. This study proposes the deformation zoning method for super-high arch dams and the implementation steps, analyzes the effect of special influencing factors of different dam zones on the deformation, introduces dummy variables that represent the special effect of dam deformation, and establishes a variable-intercept panel model for deformation zoning of super-high arch dams. Based on different patterns of the special effect in the variable-intercept panel model, two panel analysis models were established to monitor fixed and random effects of dam deformation. Hausman test method of model selection and model effectiveness assessment method are discussed. Finally, the effectiveness of established models is verified through a case study.

Connectedness percolation of hard deformed rods

NASA Astrophysics Data System (ADS)

Drwenski, Tara; Dussi, Simone; Dijkstra, Marjolein; van Roij, René; van der Schoot, Paul

2017-12-01

Nanofiller particles, such as carbon nanotubes or metal wires, are used in functional polymer composites to make them conduct electricity. They are often not perfectly straight cylinders but may be tortuous or exhibit kinks. Therefore we investigate the effect of shape deformations of the rod-like nanofillers on the geometric percolation threshold of the dispersion. We do this by using connectedness percolation theory within a Parsons-Lee type of approximation, in combination with Monte Carlo integration for the average overlap volume in the isotropic fluid phase. We find that a deviation from a perfect rod-like shape has very little effect on the percolation threshold, unless the particles are strongly deformed. This demonstrates that idealized rod models are useful even for nanofillers that superficially seem imperfect. In addition, we show that for small or moderate rod deformations, the universal scaling of the percolation threshold is only weakly affected by the precise particle shape.

Seismic anisotropy in deforming salt bodies

NASA Astrophysics Data System (ADS)

Prasse, P.; Wookey, J. M.; Kendall, J. M.; Dutko, M.

2017-12-01

Salt is often involved in forming hydrocarbon traps. Studying salt dynamics and the deformation processes is important for the exploration industry. We have performed numerical texture simulations of single halite crystals deformed by simple shear and axial extension using the visco-plastic self consistent approach (VPSC). A methodology from subduction studies to estimate strain in a geodynamic simulation is applied to a complex high-resolution salt diapir model. The salt diapir deformation is modelled with the ELFEN software by our industrial partner Rockfield, which is based on a finite-element code. High strain areas at the bottom of the head-like strctures of the salt diapir show high amount of seismic anisotropy due to LPO development of halite crystals. The results demonstrate that a significant degree of seismic anisotropy can be generated, validating the view that this should be accounted for in the treatment of seismic data in, for example, salt diapir settings.

[Dépistage précoce des retards du développement moteur: Outil de dépistage axé sur la famille].

PubMed

Harris, Susan R

2016-08-01

Décrire le test HINT (Harris Infant Neuromotor Test), un test d'évaluation du développement neuromoteur chez les nourrissons publié en 2010, qui s'appuie sur les normes canadiennes et peut être utilisé pour dépister les retards du développement moteur durant la première année de la vie. QUALITÉ DES DONNÉES: D'abondantes recherches ont été publiées sur la fiabilité intra-évaluateur, inter-évaluateur et test-retest ainsi que sur la validité convergente, prédictive, du contenu et des groupes connus du test HINT, de même que sur la sensibilité, la spécificité et les valeurs prédictives négatives et positives des inquiétudes des parents, telles qu'évaluées par le test HINT. La plupart des données probantes sont de niveau II. Il est important de diagnostiquer les retards du développement moteur durant la première année de vie, car ils sont souvent le signe de retards du développement généralisés ou de déficiences précises, telles que la paralysie cérébrale. Les inquiétudes des parents quant au développement moteur de leur enfant sont une valeur prédictive robuste de diagnostics subséquents de retard du développement moteur. Seul le dépistage précoce des retards du développement moteur, initialement par l'entremise d'outils de dépistage comme le test HINT, permet de recommander le patient à une intervention précoce qui profiterait tant à l'enfant qu'à sa famille. Copyright© the College of Family Physicians of Canada.

Wetlands of Argonne National Laboratory-East DuPage County, Illinois

DOE Office of Scientific and Technical Information (OSTI.GOV)

Van Lonkhuyzen, R.A.; LaGory, K.E.

1994-03-01

Jurisdictional wetlands of the Argonne National Laboratory-East (ANL-E) site in DuPage County, Illinois, were delineated in the summer and autumn of 1993 in accordance with the 1987 US Army Corps of Engineers methodology. Potential wetland sites with an area greater than 500 m{sup 2} (0.05 ha [0.124 acre]) were identified for delineation on the basis of aerial photographs, the DuPage County soil survey, and reconnaissance-level field studies. To qualify as a jurisdictional wetland, an area had to support a predominance of hydrophytic vegetation as well as have hydric soil and wetland hydrology. Thirty-five individual jurisdictional wetlands were delineated at ANL-E,more » totaling 180,604 m{sup 2} (18.1 ha [44.6 acres]). These wetlands were digitized onto the ANL-E site map for use in project planning. Characteristics of each wetland are presented -- including size, dominant plant species and their indicator status, hydrologic characteristics (including water source), and soil characteristics.« less

Morphological Deformities as Biomarkers in Fish from Contaminated Rivers in Taiwan

PubMed Central

Sun, Peter Lin; Hawkins, William E.; Overstreet, Robin M.; Brown-Peterson, Nancy J.

2009-01-01

Tilapia (Oreochromis spp.) were collected seasonally from four contaminated rivers in southwestern Taiwan for studies of morphological deformities that could be used as biomarkers of contamination. Morphological deformities found in tilapia were separated into 15 categories. Overall, the prevalence of deformities such as split fins, lower lip extension and gill deformities were significantly related to various water quality parameters, including low DO and high ammonium, lead and zinc concentrations. The persistence of tilapia in polluted waters and the development of a suite of morphological deformities suggest that tilapia can be used as sentinels of non-point source pollution in rivers. PMID:19742162

Appel pour une allocation intelligente dans le financement du système de santé au Cameroun

PubMed Central

Sieleunou, Isidore

2011-01-01

Le Cameroun utilise un système de budgétisation historique et une approche «top-down» pour allouer ses ressources de santé publique. Cependant, le pays compte 175 districts de santé dont les fortes disparités de nature épidémiologique, économique, géographique et culturelle, devraient être prises en compte pour réduire les iniquités en matière de sante publique. Comment comprendre alors que dans ces conditions, le budget des administrations publiques alloué aux différents districts de santé au Cameroun soit quasi identique alors que les défis sont si différents? L'inefficience allocative (mauvaise attribution du budget) générée par un tel système conduit vraisemblablement à une inefficience technique (mauvaise utilisation du budget). Pour la marche vers l'atteinte des objectifs du millénaire en matière de sante, il est impératif et urgent que les décideurs du secteur de la santé allouent de manière intelligente les ressources dans le système de santé. PMID:22355420

Description Of Scoliotic Deformity Pattern By Harmonic Functions

NASA Astrophysics Data System (ADS)

Drerup, Burkhard; Hierholzer, Eberhard

1989-04-01

Frontal radiographs of scoliotic deformity of the spine reveal a characteristic pattern of lateral deviation, lateral tilt and axial rotation of vertebrae. In order to study interrelations between deformation parameters 478 radiographs of idiopathic scolioses, 23 of scolioses after Wilms-tumor treatment and 18 of scolioses following poliomyelitis were digitized. From these the curves of lateral deviation, tilt and rotation are calculated and fitted by Fourier series. By restriction to the first harmonic, analysis reduces to the analysis of a single phase and amplitude for each curve. Justification of this simplification will be discussed. Results provide a general geometric description of scoliotic deformity.

Modelling of the plastic deformation and primary creep of metals coupled with DC in terms of the synthetic theory of irrecoverable deformation

NASA Astrophysics Data System (ADS)

Rusinko, Andrew; Varga, Peter

2018-04-01

The paper deals with modelling of the plastic and creep deformation of metals coupled with current. The passage of DC manifests itself in the increase in creep deformation and leads to primary creep time shortening. With plastic deformation, a short electric impulse results in the step-wise decrease of stress (stress-drop) on the stress-strain diagram. To catch these phenomena, we utilize the synthetic theory of recoverable deformation. The constitutive equation of this theory is supplemented by a term taking into account the intensity of DC. Further, we introduce DC intensity into the function governing transient creep. As a result, we predict the parameters of transient creep and calculate the stress-drop as a function of current intensity. The model results show good agreement with experimental data.

Soft phononic crystals with deformation-independent band gaps

PubMed Central

2017-01-01

Soft phononic crystals have the advantages over their stiff counterparts of being flexible and reconfigurable. Normally, the band gaps of soft phononic crystals will be modified after deformation due to both geometric and constitutive nonlinearity. Indeed these are important properties that can be exploited to tune the dynamic properties of the material. However, in some instances, it may be that one wishes to deform the medium while retaining the band gap structure. A special class of soft phononic crystals is described here with band gaps that are independent or almost-independent of the imposed mechanical deformation, which enables the design of phononic crystals with robust performance. This remarkable behaviour originates from transformation elasticity theory, which leaves the wave equation and the eigenfrequencies invariant after deformation. The necessary condition to achieve such a property is that the Lagrangian elasticity tensor of the hyperelastic material should be constant, i.e. independent of deformation. It is demonstrated that incompressible neo-Hookean materials exhibit such a unique property. Semilinear materials also possess this property under special loading conditions. Phononic crystals composed of these two materials are studied theoretically and the predictions of invariance, or the manner in which the response deviates from invariance, are confirmed via numerical simulation. PMID:28484331

New method of limb deformities correction in children.

PubMed Central

Atar, D.; Lehman, W. B.; Grant, A. D.; Strongwater, A.; Frankel, V. H.; Posner, M.; Golyakhovsky, V.

1992-01-01

A new "bloodless" technique (Ilizarov) was used to correct 36 limb deformities in 29 children. There were six leg length discrepancies, five achondroplasias, four deformed feet, five joint contractures, one rotational deformity of tibia, and in three the apparatus was used as an external fixator after corrective osteotomy. Lengthening was accomplished in 15 of the 16 procedures (93%). Average increase in femur length was 10 cm (32%), in tibial length 7.5 cm (30%), in humerus 11 cm (40%). Bony union was achieved in two out of five pseudoarthroses. Four deformed feet were fully corrected. Joint contractures were corrected in four out of five. The complication rate is as high as in other methods but with the Ilizarov apparatus, longer segments of bone were lengthened and more complex deformities were treated. Complications lessened as experience was gained. Images Fig. 1a,b Fig. 1 Fig. 1c Fig. 1d Fig. 1e Fig. 2a Fig. 2b Fig. 2c Fig. 2d Fig. 2e Fig. 3a Fig. 3b Fig. 3c Fig. 3d Fig. 4a Fig. 4b Fig. 4c Fig. 4d Fig. 4e Fig. 5a Fig. 5b Fig. 5c Fig. 5d PMID:1490205

40Ar* loss in experimentally deformed muscovite and biotite with implications for 40Ar/39Ar geochronology of naturally deformed rocks

USGS Publications Warehouse

Cosca, Michael; Stunitz, Holger; Bourgiex, Anne-Lise; Lee, John P.

2011-01-01

The effects of deformation on radiogenic argon (40Ar*) retentivity in mica are described from high pressure experiments performed on rock samples of peraluminous granite containing euhedral muscovite and biotite. Cylindrical cores, ~15 mm in length and 6.25 mm in diameter, were drilled from granite collected from the South Armorican Massif in northwestern France, loaded into gold capsules, and weld-sealed in the presence of excess water. The samples were deformed at a pressure of 10 kb and a temperature of 600 degrees C over a period 29 of hours within a solid medium assembly in a Griggs-type triaxial hydraulic deformation apparatus. Overall shortening in the experiments was approximately 10%. Transmitted light and secondary and backscattered electron imaging of the deformed granite samples reveals evidence of induced defects and for significant physical grain size reduction by kinking, cracking, and grain segmentation of the micas.

Numerical study of suspensions of deformable particles.

NASA Astrophysics Data System (ADS)

Brandt, Luca; Rosti, Marco Edoardo

2017-11-01

We consider a model non-Newtonian fluid consisting of a suspension of deformable particles in a Newtonian solvent. Einstein showed in his pioneering work that the relative increase in effective viscosity is a linear function of the particle volume fraction for dilute suspensions of rigid particles. Inertia has been shown to introduce deviations from the behaviour predicted by the different empirical fits, an effect that can be related to an increase of the effective volume fraction. We here focus on the effect of elasticity, i.e. visco-elastic deformable particles. To tackle the problem at hand, we perform three-dimensional Direct Numerical Simulation of a plane Couette flow with a suspension of neutrally buoyant deformable viscous hyper-elastic particles. We show that elasticity produces a shear-thinning effect in elastic suspensions (in comparison to rigid ones) and that it can be understood in terms of a reduction of the effective volume fraction of the suspension. The deformation modifies the particle motion reducing the level of mutual interaction. Normal stress differences will also be considered. European Research Council, Grant No. ERC-2013-CoG- 616186, TRITOS; SNIC (the Swedish National Infrastructure for Computing).

Reports on crustal movements and deformations. [bibliography

NASA Technical Reports Server (NTRS)

Cohen, S. C.; Peck, T.

1983-01-01

This Catalog of Reports on Crustal Movements and Deformation is a structured bibliography of scientific papers on the movements of the Earth crust. The catalog summarizes by various subjects papers containing data on the movement of the Earth's surface due to tectonic processes. In preparing the catalog we have included studies of tectonic plate motions, spreading and convergence, microplate rotation, regional crustal deformation strain accumulation and deformations associated with the earthquake cycle, and fault motion. We have also included several papers dealing with models of tectonic plate motion and with crustal stress. Papers which discuss tectonic and geologic history but which do not present rates of movements or deformations and papers which are primarily theoretical analyses have been excluded from the catalog. An index of authors cross-referenced to their publications also appears in the catalog. The catalog covers articles appearing in reviewed technical journals during the years 1970-1981. Although there are citations from about twenty journals most of the items come from the following publications: Journal of Geophysical Research, Tectonophysics, Geological Society of America Bulletin of the Seismological Society of America, Nature, Science, Geophysical Journal of the Royal Astronomical Society, Earth and Planetary Science Letters, and Geology.

Identification et prise en charge des femmes ayant des antécédents familiaux de cancer du sein

PubMed Central

Heisey, Ruth; Carroll, June C.

2016-01-01

Résumé Objectif Résumer les meilleures données portant sur les stratégies d’identification et de prise en charge des femmes qui présentent des antécédents familiaux de cancer du sein. Sources d’information Une recherche a été effectuée sur PubMed à l’aide des mots-clés anglais suivants : breast cancer, guidelines, risk, family history, management et magnetic resonance imaging screening, entre 2000 et 2016. La plupart des données sont de niveau II. Message principal Une bonne anamnèse familiale est essentielle lors de l’évaluation du risque de cancer du sein afin d’identifier les femmes qui sont candidates à une recommandation en counseling génétique pour un éventuel test génétique. On peut sauver des vies en offrant aux femmes porteuses d’une mutation au gène BRCA des interventions chirurgicales de réduction des risques (mastectomie bilatérale prophylactique, salpingo-ovariectomie bilatérale). Il faut encourager toutes les femmes qui présentent des antécédents familiaux de cancer du sein à demeurer actives et à limiter leur consommation d’alcool à moins de 1 verre par jour; certaines femmes sont admissibles à la chimioprévention. Il faut offrir aux femmes dont le risque à vie de cancer du sein est de 20 à 25 % ou plus un dépistage poussé par imagerie par résonance magnétique en plus d’une mammographie. Conclusion Une vie saine et la chimioprévention (chez les candidates) pourraient réduire l’incidence du cancer du sein; le dépistage poussé pourrait entraîner une détection plus précoce. Le fait d’aiguiller des femmes porteuses d’une mutation au BRCA vers la chirurgie de réduction des risques sauve des vies. PMID:27737991

40Ar* loss in experimentally deformed muscovite and biotite with implications for 40Ar/39Ar geochronology of naturally deformed rocks

USGS Publications Warehouse

Cosca, M.; Stunitz, H.; Bourgeix, A.-L.; Lee, J.P.

2011-01-01

The effects of deformation on radiogenic argon (40Ar*) retentivity in mica are described from high pressure experiments performed on rock samples of peraluminous granite containing euhedral muscovite and biotite. Cylindrical cores, ???15mm in length and 6.25mm in diameter, were drilled from granite collected from the South Armorican Massif in northwestern France, loaded into gold capsules, and weld-sealed in the presence of excess water. The samples were deformed at a pressure of 10kb and a temperature of 600??C over a period 29 of hours within a solid medium assembly in a Griggs-type triaxial hydraulic deformation apparatus. Overall shortening in the experiments was approximately 10%. Transmitted light and secondary and backscattered electron imaging of the deformed granite samples reveals evidence of induced defects and for significant physical grain size reduction by kinking, cracking, and grain segmentation of the micas.Infrared (IR) laser (CO2) heating of individual 1.5-2.5mm diameter grains of muscovite and biotite separated from the undeformed granite yield well-defined 40Ar/39Ar plateau ages of 311??2Ma (2??). Identical experiments on single grains separated from the experimentally deformed granite yield results indicating 40Ar* loss of 0-35% in muscovite and 2-3% 40Ar* loss in biotite. Intragrain in situ ultraviolet (UV) laser ablation 40Ar/39Ar ages (??4-10%, 1??) of deformed muscovites range from 309??13 to 264??7Ma, consistent with 0-16% 40Ar* loss relative to the undeformed muscovite. The in situ UV laser ablation 40Ar/39Ar ages of deformed biotite vary from 301 to 217Ma, consistent with up to 32% 40Ar* loss. No spatial correlation is observed between in situ 40Ar/39Ar age and position within individual grains. Using available argon diffusion data for muscovite the observed 40Ar* loss in the experimentally treated muscovite can be utilized to predict average 40Ar* diffusion dimensions. Maximum 40Ar/39Ar ages obtained by UV laser ablation overlap those

Gestion de l’anémie des patients hémodialysés chroniques: cas du Service de Néphrologie et d’hémodialyse du CHU du Point G au Mali

PubMed Central

Tounkara, Alhadji Ahmadou; Coulibaly, Abdoul Mahama Sériba; Coulibaly, Nouhoun; Traoré, Békaye; Maïga, Mahamane Kalil

2017-01-01

Introduction L'anémie est une complication fréquente de l'IRC couramment retrouvée chez les patients hémodialysés chroniques. Chez ces derniers, la prise en charge est principalement basée sur l'administration d'érythropoïétine et la supplémentation en fer. Le but de ce travail était d'évaluer la prise en charge de l'anémie des hémodialysés chroniques dans le service de Néphrologie du CHU du Point G. Méthodes Il s'agissait d'une étude transversale réalisée dans ledit service du 1er au 31 Août 2016. Résultats Au total, 63 patients sur 174 participants avaient été retenus, 34 hommes et 29 femmes avec un sex-ratio à 1,17 en faveur des hommes. L'âge moyen des patients était de 48,79 ans ± 11,59, la durée moyenne en hémodialyse était de 3,77ans ± 2,6. La fréquence hospitalière de l'anémie chez nos dialysés était de 84,12%. La transfusion sanguine était retrouvée chez 92,1%, avec une moyenne annuelle de 5,81poches ± 5,91. La supplémentation martiale était notée dans 87,3% des cas. Les moyennes respectives de ferritine et de CST étaient de 1245 ng/ml ± 629,52 et 46,16%±19,12. L'administration occasionnelle d'EPO à des doses n'excédant pas les 4000UI était rapportée par 79,4% des patients. La principale difficulté pour l'utilisation de l' EPO était le coût (74,6%). L'infection au VHC touchait 60,1% des patients ayant réalisé le dit bilan. Conclusion La gestion de l'anémie des dialysés chroniques doit être intégrée dans un cadre politique nationale de la santé. PMID:28674560

Crustal deformation and volcanism at active plate boundaries

NASA Astrophysics Data System (ADS)

Geirsson, Halldor

Most of Earth's volcanoes are located near active tectonic plate boundaries, where the tectonic plates move relative to each other resulting in deformation. Likewise, subsurface magma movement and pressure changes in magmatic systems can cause measurable deformation of the Earth's surface. The study of the shape of Earth and therefore studies of surface deformation is called geodesy. Modern geodetic techniques allow precise measurements (˜1 mm accuracy) of deformation of tectonic and magmatic systems. Because of the spatial correlation between tectonic boundaries and volcanism, the tectonic and volcanic deformation signals can become intertwined. Thus it is often important to study both tectonic and volcanic deformation processes simultaneously, when one is trying to study one of the systems individually. In this thesis, I present research on crustal deformation and magmatic processes at active plate boundaries. The study areas cover divergent and transform plate boundaries in south Iceland and convergent and transform plate boundaries in Central America, specifically Nicaragua and El Salvador. The study is composed of four main chapters: two of the chapters focus on the magma plumbing system of Hekla volcano, Iceland and the plate boundary in south Iceland; one chapter focuses on shallow controls of explosive volcanism at Telica volcano, Nicaragua; and the fourth chapter focuses on co- and post-seismic deformation from a Mw = 7.3 earthquake which occurred offshore El Salvador in 2012. Hekla volcano is located at the intersection of a transform zone and a rift zone in Iceland and thus is affected by a combination of shear and extensional strains, in addition to co-seismic and co-rifting deformation. The inter-eruptive deformation signal from Hekla is subtle, as observed by a decade (2000-2010) of GPS data in south Iceland. A simultaneous inversion of this data for parameters describing the geometry and source characteristics of the magma chamber at Hekla, and

Deformability of shredded tires

DOT National Transportation Integrated Search

1999-01-01

This report describes three separate studies that examine the deformability of shredded tire fill material. The first study determined the response of shredded tires to cyclic loading. These tests were conducted in a load frame on both constrained an...

Cyclic deformation of bidisperse two-dimensional foams

NASA Astrophysics Data System (ADS)

Fátima Vaz, M.; Cox, S. J.; Teixeira, P. I. C.

2011-12-01

In-plane deformation of foams was studied experimentally by subjecting bidisperse foams to cycles of traction and compression at a prescribed rate. Each foam contained bubbles of two sizes with given area ratio and one of three initial arrangements: sorted perpendicular to the axis of deformation (iso-strain), sorted parallel to the axis of deformation (iso-stress), or randomly mixed. Image analysis was used to measure the characteristics of the foams, including the number of edges separating small from large bubbles N sl , the perimeter (surface energy), the distribution of the number of sides of the bubbles, and the topological disorder μ2(N). Foams that were initially mixed were found to remain mixed after the deformation. The response of sorted foams, however, depended on the initial geometry, including the area fraction of small bubbles and the total number of bubbles. For a given experiment we found that (i) the perimeter of a sorted foam varied little; (ii) each foam tended towards a mixed state, measured through the saturation of N sl ; and (iii) the topological disorder μ2(N) increased up to an "equilibrium" value. The results of different experiments showed that (i) the change in disorder, ? decreased with the area fraction of small bubbles under iso-strain, but was independent of it under iso-stress; and (ii) ? increased with ? under iso-strain, but was again independent of it under iso-stress. We offer explanations for these effects in terms of elementary topological processes induced by the deformations that occur at the bubble scale.

Spinal deformity in children treated for neuroblastoma

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mayfield, J.K.; Riseborough, E.J.; Jaffe, N.

1981-02-01

Of seventy-four children who were treated at a mean age of seventeen months for neuroblastoma and survived more than five years, fifty-six had spinal deformity due either to the disease or to the treatment after a mean follow-up of 12.9 years. Of these fifty-six, 50 per cent had post-radiation scoliosis, and 16 per cent had post-radiation kyphosis, most frequently at the thoracolumbar junction, at the time of follow-up. Two kyphotic thoracolumbar curve patterns were identified: an angular kyphosis with a short radius of curvature and its apex at the twelfth thoracic and first lumbar vertebrae, and a thoracic kyphosis withmore » a long radius of curvature that extended into the lumbar spine. The post-radiation deformity - both the scoliosis and the kyphosis - progressed with growth, the scoliosis at a rate of 1 degree per year and the kyphosis at a rate of 3 degrees per year. Epidural spread of the neuroblastoma was associated with most of the cases of severe scoliosis and kyphosis. The deformity was due either to the laminectomy or to the paraplegia acting in conjunction with the radiation. Eighteen per cent of 419 children with this malignant disease survived more than five years, and of the survivors, 20 per cent had spinal deformity severe enough to warrant treatment. The factors associated with the development of spinal deformity in patient treated for neuroblastoma were: orthovoltage radiation exceeding 3000 rads, asymmetrical radiation of the spine, thoracolumbar kyphosis, and epidural spread of the tumor.« less

Analytical Approach to Large Deformation Problems of Frame Structures

NASA Astrophysics Data System (ADS)

Ohtsuki, Atsumi; Ellyin, Fernand

In elements used as flexible linking devices and structures, the main characteristic is a fairly large deformation without exceeding the elastic limit of the material. This property is of both analytical and technological interests. Previous studies of large deformation have been generally concerned with a single member (e.g. a cantilever beam, a simply supported beam, etc.). However, there are very few large deformation studies of assembled members such as frames. This paper deals with a square frame with rigid joints, loaded diagonally in either tension or compression by a pair of opposite forces. Analytical solutions for large deformation are obtained in terms of elliptic integrals, and are compared with the experimental data. The agreement is found to be fairly close.

Inconsistency in the analysis of morphological deformities in chironomidae (Insecta: Diptera) larvae.

PubMed

Salmelin, Johanna; Vuori, Kari-Matti; Hämäläinen, Heikki