WorldWideScience

Sample records for alteration comportement geochimique

  1. Geochemical behaviour of uranium in the cycle of alteration; Comportement geochimique de l'uranium dans le cycle d'alteration

    Energy Technology Data Exchange (ETDEWEB)

    Chervet, J.; Coulomb, R. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires; Soudan, P. [Centre d' Etude de Lalumine, Compagnie Pechiney (France)

    1958-07-01

    les circulations d'eaux sur les massifs granitiques et examinons l'influence de la presence de gisements d'uranium sur la composition de ces eaux. d) Nous observons l'amplitude des phenomenes qui limitent les dispersions: fixations, precipitations, etc., et le comportement de la vegetation dans les zones uraniferes. e) Enfin, l'antagonisme: alteration chimique - equilibre radioactif provoque un profond desequilibre dans les materiaux alteres. Nous essayons d'utiliser la mesure de ce desequilibre pour l'explication de mecanismes geochimiques. (auteur)

  2. Experiments on geochemical prospecting for uranium in arid country; Essais de prospection geochimique de l'uranium en pays aride

    Energy Technology Data Exchange (ETDEWEB)

    Grimbert, A.; Obellianne, J.M. [Commissariat a l' Energie Atomique, Centre d' Etudes Nucleaires de Fontenay-aux-Roses, 92 (France)

    1962-07-01

    The necessity for preliminary inquiries before applying routine geochemical prospecting techniques to the exploration of a new region is shown. Under conditions presumed to be unfavorable for geochemical prospecting as found in Nigeria along the banks of the Air, a preliminary examination showed that sampling of the stabilized superficial deposits at a depth of 15 cm made it possible to detect the presence of U-containing mineralizations hidden under about 20 meters of sterile sandy deposits. To confirm this result, a boring located on a U-containing geochemical anomaly in a paleosol, encountered a mineralized formation at a depth of 28 meters. (authors) [French] Les auteurs montrent la necessite des enquetes preliminaires avant toute application en routine des techniques geochimiques de prospection, lorsque l'on aborde une region nouvelle. Dans les conditions, a priori defavorables pour la prospection geochimique, que l'on trouve au Niger, en bordure de l'Air, une enquete preliminaire a etabli que l'echantillonnage des depots superficiels stabilises, a 15 centimetres de profondeur, permettait de deceler la presence de mineralisations uraniferes cachees sous une vingtaine de metres de sediments greseux steriles. Pour verifier ce resultat, un sondage implante sur une anomalie geochimique uranifere au sein d'un paleosol, a rencontre une formation mineralisee a 28 metres de profondeur. (auteurs)

  3. Les comportements circulaires en Algerie

    Directory of Open Access Journals (Sweden)

    S. MERABET

    2017-12-01

    Full Text Available L'économie circulaire est une alternative au schéma linéaire classique «produire, consommer, jeter» et s'inscrit dans une démarche globale de développement durable. Notre recherche se propose de montrer l'existence de ces comportements circulaires en Algérie et de mesurer l'impact de deux freins à la consommation durable que sont le manque de traçabilité des objets et l'attachement aux objets. Notre échantillon composé de 118 étudiants en psychologie à l'université de Constantine, a répondu à un outil comprenant un questionnaire de comportements circulaires, un questionnaire de Traçabilité des objets et l'échelle d'Attachement aux objets de Rioux (2014. L’analyse de régression incrémentielle ascendante qui a été menée montre que l'attachement aux objets constitue un frein à l’adoption de comportements circulaires.

  4. Alteration and long-term behaviour of different types of innovative materials for long-lived radionuclides confinement; Alteration et comportement a long terme de differentes classes de materiaux innovants pour le confinement des radionucleides a vie longue

    Energy Technology Data Exchange (ETDEWEB)

    Leturcq, G

    1998-09-29

    The present work is an experimental study on alteration mechanisms of synthetic and natural materials: aluminosilicate glasses, glass ceramics and Ti, Zr or P based ceramics. It is a part of CEA's study program on the immobilization of long- lived radionuclides and deals with chemical processes which control dissolution of amorphous and crystallized solids. The different aluminosilicate glasses studied are altered according to a process of hydrolysis of the bonds between the glass network formers; the activation energy of this reaction is about 60 kJ/mol. Alteration rates of all the glasses decrease by four orders of magnitude when the reaction progress increases. Kinetic laws based on the deviation from the thermodynamic equilibrium between leachate and the fresh solid cannot explain these great decreases. Alteration layers in the reactional interface seem to control the alteration kinetics by providing a passivation process. The chemical durability of the glass ceramics (zirconolite and titanite) improves by a factor of ten in regard to the primary glasses which were obtained by thermal treatment. Zirconium-titanate ceramics are altered only slightly by water. The altered mass corresponds to a few atomic layers only. Steady stases are quickly observed. On the basis of thermodynamic calculations, they are not correlated with saturation between the leachate and primary zirconium-titanate phases. Alteration here also ceases due to the development of a passivating layer. Models aiming at studying the chemical durability of zirconium-titanate ceramics under conditions more representative of a clayey site of geological storage were carried out. The results of the interactions of these ceramics with clays, at 708 deg.C, show clearly that there is no modification of the process of alteration, compared to the simpler pure water systems. Thus, perovskite and zirconolite do not deteriorate under these conditions. (author)

  5. Enlargement of the iliopsoas comportment

    International Nuclear Information System (INIS)

    Garcia, M.; Gonzalez, J.; Martinez, A.; Garcia, M.A.; Relea, A.; Narajo, G.

    1996-01-01

    The iliopsoas or iliopectineal comportment is a normal structure that occasionally communicates with the synovial cavity of the hip. Rarely, in association with certain pathologies that raise the intraarticular pressure, it becomes enlarged, producing an inguinal or pelvic mass, also referred to as iliopsas bursitis. We present five cases of this pathology detected over the past year in our hospitals. Three of the patients had undergone previous vascular punctures in the hip involved, one presented brucellosis-related arthropathy and the fifth had generative joint abnormalities. The plain radiography, arthrography, ultrasound, CT,CT-guided arthrography and MR images are provided and discussed. We present an etiological factor of this process (previous vascular puncture) that has not been previously reported in the literature. 13 refs

  6. Professional comportment: the missing element in nursing practice.

    Science.gov (United States)

    Clickner, Deborah A; Shirey, Maria R

    2013-01-01

    The aim of this concept analysis of professional comportment is to elucidate the dimension of nursing practice that fosters cooperation, collaboration, effective communication, and team cohesion among nurses. Professional comportment is a concept that has not been developed or analyzed, and its integration into nursing practice is unclear and not specified. The body of knowledge concentrating on the spectrum of professional comportment, civility, and lateral violence is presently incomplete. Analyzing and developing the concept of professional comportment will satisfy a gap in the literature. A concept analysis of professional comportment will clarify for the nurse the power of words, behaviors, and communication needed to achieve effective communication and civility. The Walker and Avant framework for concept analysis was used to analyze the concept of professional comportment. An electronic review of the literature through the Cumulative Index to Nursing and Allied Health Literature, Health Sources, Medical Complete, and ProQuest was conducted. This review rendered approximately 300 articles, of which 85 were reviewed. Eighteen articles informed comportment as a definition and are utilized in this analysis. The individual nurse is the level of focus in the analysis, not the organizational culture. Comportment is defined as a dignified manner or conduct. Professional comportment is critical in determining a nurse's effectiveness in relating, communicating, and collaborating with colleagues and members of the healthcare team. In the absence of professional comportment, a culture of incivility, nurse aggression, and compromised patient safety will emerge. Self-regulation and individual accountability are sequelae to professional comportment. The personal assimilation of professional comportment promotes mutual respect, harmony, commitment, and collaboration. The nurse, patient, and healthcare team are the beneficiaries of a nurse who demonstrates professional

  7. Comportements Sexuels parmi les Adolescents et Jeunes

    African Journals Online (AJOL)

    AJRH Managing Editor

    Cette étude a comme objectif spécifique d'analyser les prévalences des comportements sexuels à risque et leurs facteurs sociaux dans les pays francophones d'Afrique subsaharienne parmi les adolescents et jeunes, en mettant en exergue les diversités entre pays. Les données utilisées sont celles des Enquêtes ...

  8. Etude des comportements rheologiques des melanges de farine ble ...

    African Journals Online (AJOL)

    Etude des comportements rheologiques des melanges de farine ble/sorgho sans tanins issue de trois nouvelles varietes cultivees au Senegal et mise au point de pains a base de farines composees (ble/sorgho)

  9. ETUDE DU COMPORTEMENT DYNAMIQUE D'ACIERS A BLINDAGE

    OpenAIRE

    Meunier, Y.; Sangoy, L.; Pont, G.

    1988-01-01

    La connaissance du comportement mécanique d'aciers à blindage soumis à un chargement dynamique constitue le noeud central du schéma de prévision de la protection balistique de ces matériaux, reliant leurs propriétés métallurgiques intrinsèques à leurs caractéristiques de résistance à la perforation. Cet article présente différents travaux expérimentaux se rapportant à cette connaissance du comportement dynamique d'aciers à blindage, soumis à de grandes vitesses de déformation, sous les aspect...

  10. Scanty dressing habit and sexual comportment among adolescent ...

    African Journals Online (AJOL)

    Indulgence in scanty dressing could be curtailed by the provision of adequate sexuality education and respect for Nigerian value of dressing. Responsible sexual comportment is possible by embracing modest dressing lifestyles among others. Key Words: Scanty dressing, adolescent, aristo, HIV/AIDS, STDs, sexuality, ...

  11. Bases chimiosensorielles du comportement alimentaire chez les poissons

    OpenAIRE

    Saglio, P.

    1981-01-01

    Le comportement alimentaire, indispensable à la survie de l'individu et donc de l'espèce, occupe à ce titre une position de première importance dans la hiérarchie des comportements fondamentaux qui tous en dépendent très étroitement. Chez les poissons, cette prééminence se trouve illustrée par l'extrême diversité des supports sensoriels impliqués et des expressions comportementales qui leur sont liées. A la suite d'un certain nombre de mises en évidence neurophysiologiques et éthologiques de ...

  12. Etude Du Comportement Dynamique D'un Systeme De Pompage ...

    African Journals Online (AJOL)

    SIMULINK le comportement dynamique d'un système de pompage composé d'un générateur photovoltaïque, d'un onduleur, d'un moteur à induction et d'une pompe centrifuge. Le modèle global du système est bouclé : la sortie tension du GPV est ...

  13. Comportements Sexuels parmi les Adolescents et Jeunes en ...

    African Journals Online (AJOL)

    Cette étude a comme objectif spécifique d'analyser les prévalences des comportements sexuels à risque et leurs facteurs sociaux dans les pays francophones d'Afrique subsaharienne parmi les adolescents et jeunes, en mettant en exergue les diversités entre pays. Les données utilisées sont celles des Enquêtes ...

  14. Bases chimiosensorielles du comportement alimentaire chez les poissons

    Directory of Open Access Journals (Sweden)

    SAGLIO Ph.

    1981-07-01

    Full Text Available Le comportement alimentaire, indispensable à la survie de l'individu et donc de l'espèce, occupe à ce titre une position de première importance dans la hiérarchie des comportements fondamentaux qui tous en dépendent très étroitement. Chez les poissons, cette prééminence se trouve illustrée par l'extrême diversité des supports sensoriels impliqués et des expressions comportementales qui leur sont liées. A la suite d'un certain nombre de mises en évidence neurophysiologiques et éthologiques de l'importance du sens chimique (olfaction, gustation dans le comportement alimentaire des poissons, de très importants secteurs d'études électrophysiologiques et d'analyses physico-chimiques visant à en déterminer la nature exacte (en termes de substances actives se sont développés ces vingt dernières années. De tous ces travaux dont les plus avancés sont présentés ici, il ressort que les acides aminés de série L plus ou moins associés à d'autres composés de poids moléculaires < 1000 constituent des composés chimiques jouant un rôle déterminant dans le comportement alimentaire de nombreuses espèces de poissons carnivores.

  15. Analysis of working conditions and comportment of prevention in radiation protection

    International Nuclear Information System (INIS)

    Bouhnik, C.

    1992-01-01

    In this article, the author presents analysis methods of working conditions( environment of working stations, working stress, socio-technical environment, ability and, emotion and relation phenomena) that permit to understand how the prevention comportment is regulated

  16. Effets du travail du sol sur le comportement chimique et biologique ...

    African Journals Online (AJOL)

    Effets du travail du sol sur le comportement chimique et biologique du sol et les conséquences sur le rendement d'un blé tendre (Triticum aestivum L.) dans la région « non chernozem » de la fédération de Russie.

  17. Grounding cultural syndromes : Body comportment and values in honor and dignity cultures

    NARCIS (Netherlands)

    Ijzerman, H.; Cohen, D.

    2011-01-01

    The body is a carrier of relatively complex cultural values. Three experiments examined links between body comportment and honor (a cultural syndrome prizing female chastity, familial loyalty, and reputation). We put participants from nonhonor (Anglo-Americans; Experiment 1) and honor (Latinos;

  18. Comportement alimentaire et évolution pondérale des moutons ...

    African Journals Online (AJOL)

    Diet samples were analysed by NIRS system to determine the chemical composition. In vitro gas production allowed the ... Keywords: Comportement alimentaire, Moutons Djallonké, fourrages, performances, Bénin.; Grazing behaviour, Djallonke sheeps, forage, performances, Benin Annales des Sciences Agronomiques du ...

  19. Comportement agronomique et sanitaire de nouvelles lignées de ...

    African Journals Online (AJOL)

    SARAH

    31 août 2015 ... Objectif: Déterminer les performances agronomiques de nouvelles lignées de piment (Capsicum sp) dont huit introduites de ... Mots clés : Piment, Capsicum sp, lignées, comportement agronomique, flétrissement bactérien, maladies fongiques. ...... markers linked to Phytophthora root rot resistance in ...

  20. La formation du comportement de plainte chez le consommateur: recherche exploratoire chez des usagers de restaurants

    OpenAIRE

    Moliner Velázquez, Beatriz; Berenguer Contrí, Gloria; Gil Saura, Irene

    2011-01-01

    Cette recherche aborde le processus de formation du comportement de plainte chez le consommateur. L´objectif général est d´approfondir sur la nature de ce type de réponse à l´insatisfaction, en décrivant sa formation à partir des apports d´un ensemble de variables puisées dans la littérature. En partant du fait que le comportement de plainte englobe trois types de réponses (de plainte, vis à vis des tiers, et privé), nous analysons l´effet provoqué par le niveau d´insatisfaction, la probabili...

  1. Comportement visco-hyperélastique d'un silicone de faible dureté

    OpenAIRE

    GERVILLERS, S; ALAOUI SOULIMANI, A; EHRLACHER, A

    2003-01-01

    Nous présentons l'étude complète du comportement visco-hyperélastique d'un silicone de faible dureté. L'identification du comportement hyperélastique est effectuée à partir d'essais de traction et compression uniaxiaux complétés par un essai triaxial afin de mesurer la compressibilité du matériau. L'identification de la partie viscoélastique se fait à partir d'un essai de relaxation, la théorie étant celle de la viscohyperélasticité utilisant des modules de relaxation sous forme de série de P...

  2. Comportement différé des marnes du tunnel d'Arbus (France ...

    African Journals Online (AJOL)

    DK

    2Laboratoire de Mécanique des Roches, Ecole Polytechnique Fédérale de Lausanne, Suisse. Soumis le : 26.03.2013. Révisé le : 26.01.2014 ... contrainte et à l'action de l'eau. L'historique des chargements et la présence d'eau ... Les géomatériaux et les roches en particulier ont un comportement mécanique complexe qui.

  3. Influence de l\\'addition d\\'inhibiteurs azotés sur le comportement ...

    African Journals Online (AJOL)

    Influence de l\\'addition d\\'inhibiteurs azotés sur le comportement électrochimique et métallurgique de fontes au chrome-nickel (pompes d\\'extraction) en milieu ... en évidence l\\'existence d\\'un film très mince à la surface de la fonte Fa et d\\'une couche épaisse et poreuse de produits de corrosion à la surface de la fonte Fb.

  4. Etude du comportement de deux variétés de manioc en culture in ...

    African Journals Online (AJOL)

    Les techniques de multiplication peu améliorées du manioc associées aux problèmes de maladies bactériennes et virales participent à la régression de son rendement. Le but de cette étude est d'analyser le comportement de deux variétés de manioc en culture in vitro puis l'impact de cette technique sur la qualité de l'ADN ...

  5. Origin and geochemical behavior of uranium in marine sediments. Utilization of the {sup 234}U/{sup 238}U ratio in marine geochemistry; Origine et comportement geochimique de l`uranium dans les sediments marins. Utilisation du rapport ({sup 234}U/{sup 238}U) en geochimie marine

    Energy Technology Data Exchange (ETDEWEB)

    Organo, Catherine [Paris-11 Univ., 91 - Orsay (France)

    1997-01-20

    The first part of this thesis presents the current situation of knowledge of uranium in marine environment. The second part describes the methods of analysis as well as the material support of the study, i.e., the sediments and marine deposits investigated. The third part is dedicated to the study of uranium mobility in marine sediments characterized by detrital terrigenous composition (pelagic clays). This approach allowed quantifying the entering and leaving flux of uranium after the sediment settling and, to discuss, on this basis, the consequences on the uranium oceanic balance. In the third part the origin and behavior of uranium in zones of high surface productivity is studied. The uranium enrichments observed in the hemi-pelagic sediments of the EUMELI (J.G.O.F.S.-France) programme will constitute a material of study adequate for measuring the variations in the {sup 234}U/2{sup 38U} ratio in solid phase, in response to the oxido-reducing characteristics of the sediment. Thus establishing the origin of the trapped uranium has been possible. Also, the nature of the sedimentary phases related to uranium in bio-genetic sediments in the Austral Ocean was determined. Thus a relationship between the variations in the {sup 234}U/{sup 238} and the diagenetic transformations was possible to establish. Finally in the fifth part a study of the behavior of uranium in a polymetallic shell characteristic for deposits of hydrogenized origin 146 refs., 57 figs., 23 tabs.

  6. Geochemical controls of the oils acidity in petroleum reservoirs; Controles geochimiques de l'acidite des huiles dans les reservoirs petroliers

    Energy Technology Data Exchange (ETDEWEB)

    Rouquette, N.

    2004-12-01

    Within the framework of this thesis, we were interested in the study of acid oils. Thus, after having developed an analytical method to separate acids from crude oils, this one was applied to the analysis of several series of acid oils presenting various degrees of biodegradation. In the first chapter devoted to their molecular study, it was shown that the alteration of the organic matter proceeds according to a quasi-stepwise order and that the major part of the carboxylic acids appeared as an Unresolved Complex Mixture. The only identified resolved compounds were apparently not formed by biodegradation of the oil in place but rather seem either to have been incorporated during oil migration, or to correspond to compounds initially present in the reservoir rock. Among those, we isolated and identified by NMR a new higher plant tri-terpenic derivative, the 24-nor,28-lupanoic acid. In the second chapter, a new method to evaluate acidity, applicable to small quantities of oil, was developed. This one is based on the methylation of the acid species by iodo-methane marked with carbon 13. In the case of a series from the Gulf of Guinea tested initially, the enrichment after labelling presents a perfect correlation with the values of acidity measured by the TAN method (for 'Total Acid Number'). The isotopic labelling method was applied later to a broader range of oil samples. As a whole, a linear correlation seems to exist between {sup 13}C labelling and TAN index, which lets consider that this method could represent an interesting alternative to the measurement of the TAN index in oil exploration. (author)

  7. Domestication et comportement chez les poissons téléostéens

    OpenAIRE

    Bégout Anras, M.L.; Lagardère, J.P.

    2004-01-01

    Un des principaux objectifs de la domestication est de sélectionner des lignées à haut potentiel de croissance et à faible agressivité. L’étude des caractéristiques des animaux domestiqués montre souvent de nombreux changements comportementaux dus aux conditions d’élevage, mais très peu de données sont disponibles chez les poissons. Cet article décrit d’abord comment la mise en élevage affecte certains comportements, notamment alimentaires et natatoires, puis présente les modifications, au co...

  8. Comportement à la corrosion de couches minces nano structurées ...

    African Journals Online (AJOL)

    Nous avons élaboré par pulvérisation cathodique magnétron DC des couches minces nano structurées en alliages de fer–Silicium Fe1-xSix. Le comportement à la corrosion en milieu chloruré (H2O - 3,2 g/l NaCl) a été analysé. Nous avons constaté que les meilleures performances électrochimiques sont obtenues pour les ...

  9. Une fourmi sur la plage. Remarques sur les concepts d’agent et de comportement

    OpenAIRE

    Volken, Henri

    2009-01-01

    An ant, viewed as a behaving system, is quite simple. The apparent complexity of its behavior over time is largely a reflection of the complexity of the environment in which it finds itself.H. A. Simon [10](Une fourmi considérée comme un système comportemental, est un être relativement simple. L’apparente complexité des évolutions de son comportement est pour une grande part le reflet de la complexité de l’environnement dans lequel elle se trouve.) A man, viewed as a behaving system, is quite...

  10. Mise au point d'un test in vitro de comportement au sel de quatre ...

    African Journals Online (AJOL)

    L'utilisation d'un porte-greffe résistant à ces conditions apparaît la solution la plus adaptée. Objectifs : Cette étude est la comparaison de comportement de génotypes d'agrumes, en termes de résistance à la salinité in vitro au niveau des cals et des cellules cultivées parallèlement sur milieu liquide et solide. Méthodologie ...

  11. ETUDE DU COMPORTEMENT MECANIQUE DES ACIERS HYPEREUTECTOIDES DANS LE DOMAINE DE TEMPERATURE INTERCRITIQUE DYNAMIQUE

    Directory of Open Access Journals (Sweden)

    R GHERIANI

    2001-06-01

    Full Text Available L'étude que nous présentons contribue à une meilleure compréhension de l'influence de la vitesse de déformation et de la température sur le comportement mécanique des aciers hypereutectoïdes dans le domaine de température intercritique dynamique. Les courbes expérimentales obtenues en torsion présentent un intérêt notable dans la mesure où elles permettent de caractériser le comportement mécanique de l'acier 100C6; de plus, elles fournissent  des informations précieuses sur la capacité maximale de déformation de l'alliage. Les essais de torsion, menés jusqu'à rupture des éprouvettes, permettent d'effectuer un classement des matériaux selon leur ductilité. Les résultats obtenus sur l'acier 100C6 ont permis de préciser le comportement mécanique à tiède  de cet acier. Les aciers hypoeutectoïdes présentent, dans les domaines de température compris entre Ac1 et Ac3 en condition dynamique, une capacité de déformation élevée résultant de l'évolution, en cours de déformation, des phases a et g et de leurs mécanismes d'adoucissement. Nous nous sommes alors posé la question: quel est le comportement d'un acier hypereutectoïde, donc ne présentant  pas de domaine biphasé (a + g à l'équilibre, lorsqu'il est déformé à une température supérieure à Ac1?

  12. Comportement de la xonotlite exposée aux hautes températures

    Science.gov (United States)

    Baux, C.; Daiguebonne, C.; Lanos, C.; Guillou, O.; Jauberthie, R.; Gérault, Y.

    2004-11-01

    Afin de modéliser le comportement thermomécanique de matériaux dédiés à la protection incendie, l'étude de leur comportement thermophysique est mise en œuvre. Le produit composite étudié est essentiellement composé de xonotlite, un silicate de calcium hydraté renforcé par des fibres organiques de type cellulose. Différentes méthodes d'analyses sont utilisées pour suivre l'évolution de la structure du produit soumis à un incendie (T > 1000circC et présence de flammes) : mesures ATD/TG, diffraction des rayons X (température ambiante ou thermodiffraction). Les résultats de ces analyses sont croisés avec des visualisations MEB. L'analyse de l'évolution des phases cristallines associée à une évolution importante et rapide de température permet de comprendre comment le matériau supporte l'incendie. L'identification de ses conditions de ruine du produit découle de cette étude.

  13. Comportements à risque et maladies cardio-vasculaires. Comment infléchir le cours des choses?

    OpenAIRE

    Etienne, Anne-Marie; Krzesinski, Jean-Marie; André, Jean-François

    2014-01-01

    «Comportements à risques et maladies cardio-vasculaires, comment infléchir le cours des choses ?» Entre recommandations, croyances et attitudes des médecins, croyances, attitudes et vécu des patients, comment améliorer la prévention dans le domaine cardio-vasculaire ?

  14. Comportement en flexion des bétons fibrés sous chargement cyclique

    OpenAIRE

    Boulekbache Bensaid; Hamrat Mostefa; Chemrouk Mohamed; Amziane Sofiane

    2014-01-01

    Ce papier présente les résultats d’une étude expérimentale sur le comportement en flexion des bétons de fibres métalliques. On étudie l’effet de la rhéologie du béton sur l’orientation des fibres et l’influence de l’orientation sur les propriétés mécaniques. La rigidité de l’ancrage des fibres étudiée par les essais cycliques est liée aux caractéristiques rhéologiques et mécaniques de la matrice. Les résultats montrent que la fluidité des bétons est un paramètre essentiel de l’orientation des...

  15. Étude du comportement anisotrope de l'argile de Boom

    OpenAIRE

    DAO, Linh Quyen

    2015-01-01

    Dans le cadre de la déposition géologique profonde des déchets radioactifs, l'argile de Boom est choisie comme une des formations hôtes potentielles dans le programme belge. Par sa formation géologique, cette argile est considérée comme un matériau isotrope transversal. En effet, l'anisotropie de ses propriétés hydraulique et thermique a été mise en évidence dans plusieurs études. Il apparait maintenant nécessaire de mener une étude complète sur son comportement anisotrope. Sur le plan expéri...

  16. Psychology as a Science of Subject and Comportment, beyond the Mind and Behavior.

    Science.gov (United States)

    Pérez-Álvarez, Marino

    2018-03-01

    The turn of qualitative inquiry suggests a more open, plural conception of psychology than just the science of the mind and behavior as it is most commonly defined. Historical, ontological and epistemological binding of this conception of psychology to the positivist method of natural science may have exhausted its possibilities, and after having contributed to its prestige as a science, has now become an obstacle. It is proposed that psychology be reconceived as a science of subject and comportment in the framework of a contextual hermeneutic, social, human behavioral science. Thus, without rejecting quantitative inquiry, psychology recovers territory left aside like introspection and pre-reflective self-awareness, and reconnects with traditions marginalized from the main stream. From this perspective psychology might also recover its credibility as a human science in view of current skepticism.

  17. Influence De la Température sur Le Comportement Physique Et Electronique des Transistors MOS

    OpenAIRE

    ZIANI CHERIF, Sidi Mohamed

    2010-01-01

    Notre travail consiste à étudier l'influence de la température sur le comportement physique et électronique des transistors MOSFET à canaux courts en utilisant un modèle de dernière génération l'EKV (Ens Krummenacher and Vittoz) qui est un modèle évolutif et compact de simulation se basant sur les propriétés physiques fondamentales de la structure MOS. Dans un premier temps, nous avons tout d’abord fait une étude théorique sur les transistors MOS où on a rappelé les notions de base et expliqu...

  18. Comportement et cognition : ce que nous apprend un mini-cerveau

    OpenAIRE

    Giurfa, Martin

    2017-01-01

    Les insectes ont été considérés habituellement comme de simples petites machines à réflexes. D’après cette vision particulière, leur comportement serait essentiellement gouverné par des réactions stéréotypées, laissant peu de place à des phénomènes de plasticité. Cette vision, qui exclut donc la possibilité de s’attaquer à des problématiques liées à la cognition animale sur les insectes, a inspiré un nombre important de travaux en robotique. Elle ignore, cependant, que les insectes, comme la ...

  19. Modélisation du comportement et des couplages HMC des milieux poreux

    OpenAIRE

    Hoang , Ha

    2012-01-01

    Modelling of the behavior and the couplings HMC of the porous circles; La modélisation du comportement hydromécanique chimique des milieux poreux saturés et non saturés est abordée au niveau microscopique et mésoscopique. Au niveau microscopique la modélisation des écoulements diphasiques est basée sur une représentation du réseau poral comme un ensemble de tubes dont les orientations et les rayons sont choisis sur un principe d’équivalence avec les pores. L’algorithme régissant la génération...

  20. Espace de comportement et espace microgéographique: le jeu de la «Révolution Verte»

    Directory of Open Access Journals (Sweden)

    Peter GOULD

    1987-03-01

    Full Text Available Les relations bidimensionnelles sont examinées entre les joueurs dans l'espace microgéographique de la salle de jeu et dans l'espace de comportement engendré par les interactions qu'ils perçoivent. Les asymétries sont interprétées comme étant des «vents de pauvreté» et des effets de comportement antisocial. L'analyse cartographique combinée à la multidimensionnalité et à la régression euclidienne crée des intuitions sur de simples relations structurelles qui restent à examiner.

  1. Comportement et cognition animale : le statut de la stéréotypie et de la variabilité

    OpenAIRE

    Kreutzer, Michel

    2017-01-01

    Voir le comportement pour comprendre le mental ? Imaginons un oiseau qui chante dans un arbre au printemps. Étudier les relations qu'entretient cet animal avec son environnement physique et social nécessite de prendre en compte trois dimensions. Il y a bien sûr une première dimension, facile à objectiver, ce comportement de chant lui-même et les réactions qu'il suscite : parades d'attaque des congénères mâles pour défendre le territoire et attraction, séduction des congénères femelles pour se...

  2. Comportement des sédiments marins carbonatés Behaviour of Marine Carbonate Sediments

    Directory of Open Access Journals (Sweden)

    Nauroy J. F.

    2006-11-01

    Full Text Available Les sédiments carbonatés recouvrent les fonds marins de nombreuses zones d'activités pétrolières actuelles. La méconnaissance des caractéristiques mécaniques de ces sols explique en partie les difficultés rencontrées pour l'implantation de structures marines. Un important programme d'essais réalisés sur divers sédiments carbonatés a été effectué afin de préciser : - la définition d'une méthodologie d'identification de ces sédiments ; - l'influence de leurs caractéristiques physiques sur leur comportement mécanique. Le comportement des sédiments carbonatés, soumis à des sollicitations cycliques simulant l'action de la houle sur les fondations d'ouvrages en mer, a été longuement étudié à l'appareil triaxial et sur un modèle réduit de similitude de fondation de structure à embase poids en utilisant la technique de centrifugation. Les essais réalisés confirment l'importance du seuil caractéristique comme limite fondamentale dans l'étude des sables carbonatés sous chargement cyclique. Carbonate sediments cover the seabed of many areas where petroleum activities are now taking place. Incomplete understanding of the mechanical properties of such formations partly explains the difficulties encountered in installing offshore structures. An extensive testing program involving different carbonate sediments has been carried out for two reasons : (1 to define a methodology for identifying these sediments, and (2 to determine the influence of their physical properties on their mechanical behavior. The behavior of carbonate sediments subjected to cyclic loading, simulating wave action on offshore structures, foundations, has been intensively investigated, using a triaxial devise and with a scale model simulating the foundation of a gravity structure using the centrifuging technique. These tests confirm the importance of the characteristic threshold as the fundamental limit in investigating carbonate sands under cyclic

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

    Science.gov (United States)

    Monteil, C.; Amouroux, M.

    1997-02-01

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

  4. ETUDE DU COMPORTEMENT MECANIQUE DU BETON CELLULAIRE AUTOCLAVE PRODUIT EN ALGERIE

    Directory of Open Access Journals (Sweden)

    R BELOUETTAR

    2002-12-01

    Full Text Available Ce travail présente une étude expérimentale du comportement mécanique du béton cellulaire autoclavé. L’étude est portée essentiellement sur une série d’essais mécaniques en compression quasistatique à différentes vitesses de déformation variables entre 10-4 s-1 et 10 s-1 et à deux états différents (état sec et état saturé d’eau. En général, l’augmentation de la vitesse de déformation donne une augmentation de la contrainte critique du béton cellulaire autoclavé. Le béton cellulaire autoclavé présente une sensibilité à la vitesse de déformation positive. La valeur du module d’élasticité est proche de la valeur standard (1.5 GPa pour un béton cellulaire autoclavé de masse volumique égale à 500-550 kg/m3.

  5. Comportement d’une Chaussée Souple sur Sol Support Gonflant

    Directory of Open Access Journals (Sweden)

    Djellali Adel

    2014-04-01

    Full Text Available Les déformations des sols fins sont la cause majeure des détériorations des chaussées souples. Elles sont en relation avec les conditions climatiques qui favorisent la variation de l’état hydrique (fluctuation de la teneur en eau accentués par une augmentation ou diminution du volume de sol. Cet article présente une étude géotechnique spécifique complète, il détermine la cause principale des dégradations des chaussées souples sur sols gonflants, par indication que le gonflement est le générateur de ces dégâts. Les données ont été traitées par une analyse statistique en composante principale ACP. Le code de calcul Plaxis à été utilité pour vérifier les déplacements verticaux du corps de chaussée et d’étudier le comportement de ces sols vis-à-vis au remblai et du corps de la chaussée.

  6. Le comportement des thons tropicaux autour des objets flottants: de l'étude des comportements individuels et collectifs à l'étude du piège écologique

    OpenAIRE

    Robert, Marianne

    2012-01-01

    Les recherches en halieutique ont pour objectif d’améliorer les connaissances sur le fonctionnement des populations de poissons afin de transférer celle-ci vers des outils de gestion. Ce travail de thèse repose sur un ensemble d’expériences et de modélisations destinées à approfondir notre compréhension générale du comportement associatif de poissons grands pélagiques avec des objets flottants à la surface de l’océan. Notre objectif est de tester si les milliers d’objets flottants artificiels...

  7. Comportement au dégel des sols silteux Thaw Behavior in Silty Soils

    Directory of Open Access Journals (Sweden)

    Montarges R.

    2006-11-01

    Full Text Available Les problèmes géotechniques relatifs à l'offshore arctique concernent essentiellement le tassement et la dégradation mécanique des sols au dégel. Dans la perspective d'évaluation de l'importance de ces problèmes l'IFP, avec le concours du Laboratoire de Glaciologie et Géophysique de l'environnement, a entrepris en 1986-87, une étude méthodologique des sols au dégel. Deux sols silteux (un silt sableux et un silt argileux, de comportement au gel très différent, ont été utilisés pour cette étude préliminaire. L'interprétation des résultats obtenus, dans les domaines de la structure des sols gelés et de l'évolution de leurs caractéristiques mécaniques (tassement et résistance au cisaillement, montre l'influence prédominante de la présence des minéraux argileux. Les résultats de cette étude préliminaire sont brièvement examinés en terme d'application aux problèmes d'exploitation pétrolière en zones arctiques. La poursuite de l'expérimentation apparaît nécessaire notamment pour évaluer correctement l'incidence du comportement au dégel des sols sur la subsidence associée aux risques d'instabilité des conduites rigides ou flexibles. Geotechnical problems related to offshore arctic activities mainly concern the settling and mechanical degradation of soils as the result of thawing. In the outlook for assessing the importance of such problems, IFP, with the assistance of the Laboratoire de Glaciologie et Géophysique de l'Environnement, began methodological research in 1986-1987 on the effect of thawing on soils. Two silty soils (one sandy silt and one clayey silt having very different thaw behaviors were used for this preliminary study. The interpretation of the results obtained in the fields of frozen soil structure and the evolution of their mechanical properties (settling and shear strength shows the predominant influence of the presence of clayey minerals. The results of this preliminary study are examined

  8. Fonction des comportements parentaux: révision de la notion de sensibilité maternelle

    Directory of Open Access Journals (Sweden)

    Gosselin Catherine

    2000-01-01

    Full Text Available Le rôle exercé par la mère dans l'adaptation de l'enfant et la prépondérance des soins maternels prodigués à l'enfant en bas âge représentent une des pierres d'assise de la théorie de l'attachement. Bien que les études empiriques aient largement démontré le lien entre la sécurité de l'attachement et le développement des compétences chez l'enfant, peu d'information sur les comportements liés à la continuité de la fonction parentale est disponible. Dans la perspective d'une meilleure compréhension de la continuité du rôle de protection parentale chez la mère, cet article théorique propose une révision de la sensibilité maternelle selon un modèle de régulation des buts empathiques, socialisants et personnels. La présentation de ce modèle s'appuie sur la théorie de l'attachement élaborée par John Bowlby, sur le concept de sensibilité maternelle développée par Mary Ainsworth et sur le modèle de la régulation des buts parentaux de Théodore Dix.

  9. Fonction des comportements parentaux: révision de la notion de sensibilité maternelle

    Directory of Open Access Journals (Sweden)

    Catherine Gosselin

    Full Text Available Le rôle exercé par la mère dans l'adaptation de l'enfant et la prépondérance des soins maternels prodigués à l'enfant en bas âge représentent une des pierres d'assise de la théorie de l'attachement. Bien que les études empiriques aient largement démontré le lien entre la sécurité de l'attachement et le développement des compétences chez l'enfant, peu d'information sur les comportements liés à la continuité de la fonction parentale est disponible. Dans la perspective d'une meilleure compréhension de la continuité du rôle de protection parentale chez la mère, cet article théorique propose une révision de la sensibilité maternelle selon un modèle de régulation des buts empathiques, socialisants et personnels. La présentation de ce modèle s'appuie sur la théorie de l'attachement élaborée par John Bowlby, sur le concept de sensibilité maternelle développée par Mary Ainsworth et sur le modèle de la régulation des buts parentaux de Théodore Dix.

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

    Science.gov (United States)

    Levesque, Julie

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

  11. ETUDE COMPARATIVE DU COMPORTEMENT A L’USURE DE CERTAINES NUANCES DE CERAMIQUE DE COUPE EN TOURNAGE

    Directory of Open Access Journals (Sweden)

    M A YALLESE

    2002-06-01

    Full Text Available Des essais de coupe ont été effectués par quatre outils en céramique, face à l’acier  AF37. Les résultats de ces essais nous ont permis d’étudier l’influence  des paramètres de coupe sur le comportement à l’usure des différentes céramiques étudiées. Pour ces différentes céramiques la relation entre la tenue et les paramètres de coupe a été exprimée suivant le modèle mathématique de Taylor.

  12. Modélisation micromagnétique du comportement magnéto- mécanique

    OpenAIRE

    Mballa-Mballa , Frederick ,; Hubert , Olivier; Song , He; Depeyre , Sophie; Meilland , Philip

    2013-01-01

    National audience; Le comportement mécanique des aciers dual-phases (DP) est réputé fortement sensible à leur microstructure. Un contrôle en ligne magnétique est envisagé. Ce contrôle nécessite la mise au point d'une approche inverse incluant une description fine des liens existant entre la microstructure et les propriétés magnétiques. Dans le cadre d'une formulation couplée magnéto-mécanique, il est néces-saire d'introduire une source supplémentaire d'anisotropie à travers le potentiel magné...

  13. Les besoins en oxygène des poissons marins et leur comportement en conditions hypoxiques (revue bibliographique)

    OpenAIRE

    Person-le Ruyet, Jeanine

    1986-01-01

    Les données expérimentales relatives aux besoins en oxygène des poissons marins (pélagiques et démersaux) sont rappelées. Les variations de la consommation d'oxygène en fonction du poids (w) sont généralement décrites par l'équation : M02 (ml/h) = 0,33 W0. 80 Le comportement général des poissons en conditions hypoxiques et leurs limites de tolérance sont de même considérés en fonction du stade de développement.

  14. Contribution à l'étude du comportement des milieux pulvérulents. "Micro-rhéologie et état statistique des milieux granualaires"

    OpenAIRE

    Lorin De La Grandmaison , Didier

    1980-01-01

    Etude réalisée à partir de travaux de recherche effectués au Centre Expérimental du Bâtiment et des Travaux Publics pour la compréhension du comportement mécanique des sols en tant que milieux granulaires. Le problème de contact intergranulaire est abordé du point de vue de la mécanique rationnelle et du point de vue de la loi de comportement. Formulation de caractéristiques statistiques de l'état mécanique d'un milieu granulaire. Il s'agit du prolongement à un milieu des paramètres d'état d'...

  15. Observations sur le comportement alimentaire de la population de truites communes (Salmo trutta L. dans la rivière Estoräos, Portugal

    Directory of Open Access Journals (Sweden)

    VALENTE A.

    1990-07-01

    Full Text Available L'étude du comportement alimentaire d'une population de truites, Salmo trutta L., est abor-dée dans la rivière Estoräos, au nord du Portugal. L'étude des macroinvertébrés benthiques et en dérive montre une composition comparable à celle d'autres rivières européennes. La fréquence d'occurrence des organismes proies ingérés met en évidence la diversité du choix alimentaire, plus marquée chez les poissons 1+. Le comportement alimentaire opportuniste de l'espèce est confirmé. L'analyse en composantes principales révèle des similitudes entre le spectre trophique des deux groupes d'âge étudiés. Le comportement alimentaire ne semble pas responsable des faibles croissance et densité de cette population détruites.

  16. Smectite alteration

    International Nuclear Information System (INIS)

    Anderson, D.M.

    1984-11-01

    This report contains the proceedings of a second workshop in Washington DC December 8-9, 1983 on the alteration of smectites intended for use as buffer materials in the long-term containment of nuclear wastes. It includes extended summaries of all presentations and a transcript of the detailed scientific discussion. The discussions centered on three main questions: What is the prerequisite for and what is the precise mechanism by which smectite clays may be altered to illite. What are likly sources of potassium with respect to the KBS project. Is it likely that the conversion of smectite to illite will be of importance in the 10 5 to the 10 6 year time frame. The workshop was convened to review considerations and conclusions in connection to these questions and also to broaden the discussion to consider the use of smectite clays as buffer materials for similar applications in different geographical and geological settings. SKBF/KBS technical report 83-03 contains the proceedings from the first workshop on these matters that was held at the State University of New York, Buffalo May 26-27, 1982. (Author)

  17. Etude Petrographique et Geochimique du Complexe Annulaire de ...

    African Journals Online (AJOL)

    Geochemical point view, this fenitization is marked by a decrease of the Si2O, Al2O3 and an enrichment in Na2O, Fe2O3, MgO, P2O5, Ce, La, Nb. The carbonatites of the principal body and dykes are characterized by the abundance of the carbonates (calcite and dolomite) and the apatite presence, amphibole, magnétite, ...

  18. COMPORTEMENT D’UN COMPOSITE FINE MINERALE - CIMENT - BOIS ELABORE A L’AIDE DE DECHETS INDUSTRIELS SOLIDES

    Directory of Open Access Journals (Sweden)

    M.L BENMALEK

    2000-06-01

    Full Text Available Cinq fines minérales de différentes natures minéralogiques et de limites granulaires comparables, provenant de résidus de carrières, ont été traitées pour former le squelette de bétons légers d'isolation. L'allégement et le pouvoir isolant de ces bétons sont obtenus par incorporation de granulats de bois dans la matrice constituée de la fine minérale et de ciment CPA. Dans une première partie, sont présentés les principales caractéristiques de ces fines: minéralogie par diffraction des rayons X, granulométrie laser, conductivité thermique à la sonde TPS, densité sèche par  pycnomètrie à eau et morphologie au MEB. La seconde partie est consacrée à l'étude de l'effet des caractéristiques de ces fines sur le comportement hygrothermique et mécanique de ces bétons élaborés avec une même formulation et un même état de consistance au moulage. Les résultats de ces investigations sont comparés entre eux et  à ceux de matériaux usuels classés par la RILEM.

  19. Consommation de miel d’abeilles: analyse des comportements des mangeurs de l’État de Santa Catarina – Brésil

    OpenAIRE

    Cheung-Lucchese, T.; Gerber, R.M.

    2010-01-01

    Des analyses sur les comportements alimentaires des mangeurs rendent possible que d’importantes informations concernant les différentes manières dont ils interprètent leur alimentation soient révélées. Comme les individus ont d’intérêts divers à propos de leur alimentation, l’objectif principal de cette étude repose sur la réalisation d’une typologie de consommateurs de miel qui vise à connaître le profil des consommateurs et leurs façons d’interpréter cette consommation. La population intérr...

  20. Existe-t-il un lien entre les comportements alimentaires de l'enfant et les pratiques éducatives familiales ? : http://www.vitagora.com/fr/

    OpenAIRE

    2010-01-01

    2 février 2010. OPALINE (l'Observatoire des Préférences Alimentaires de l'Enfant et du Nourrisson), projet de recherche qui a démarré en 2005, arrivera à sa fin mi-2011. Dans le cadre de ce projet, labellisé par Vitagora et financé notamment par l'ANR et la région Bourgogne, plusieurs résultants marquants ont été enrégistrés. L'un des volets du projet porte sur les pratiques éducatives des parents et l'impact sur les comportements alimentaires des enfants.

  1. Comprendre le développement précoce du comportement et des préférences alimentaires chez les enfants

    OpenAIRE

    Nicklaus, Sophie

    2015-01-01

    Les préférences alimentaires, comme beaucoup de comportements, s'apprennent, sous l'effet des expériences. Ayant étudié depuis plus de 15 ans les préférences alimentaires des enfants, je montrerai le fruit de nos recherches sous une forme ludique, en expliquant comment faire aimer les légumes aux enfants à partir des résultats obtenus dans le cadre de l'étude OPALINE (Observatoire des Préférences Alimentaires du Nourrisson et de l'Enfant). J'expliquerai l'importance des premiers apprentissage...

  2. Time-scales of erosion and weathering processes in the Himalayan river system: Element and isotope approach using the U-series; Constantes de temps des processus d'erosion et d'alteration dans le systeme himalayen: approche geochimique elementaire et isotopique par les series de l'uranium

    Energy Technology Data Exchange (ETDEWEB)

    Granet, M

    2007-06-15

    The time-scales of erosion and weathering processes are key parameters which need to be determined to understand the response of the reliefs to external forcing like tectonics, climate and human activities. They were recovered by using U-series nuclides analyzed in sediments and suspended materials carried by the Himalayan rivers of the Ganges and Brahmaputra basins. In the Ganges basin, the time-scales of weathering determined from the study of coarse sediments carried by the Kali Gandaki range from several ky, where the uplift is located, to 350 ky. Such values indicate that the bed-rocks are in situ weathered for a long period before the weathering residual products get transported in the rivers as coarse sediments. At the outlet of the high range, these sediments are carried by the tributaries of the Ganges, the Gandak and Ghaghara, during a transfer period of about 100 ka. The study of the sediments at the outlet of the Brahmaputra tributaries allows to propose time-scales of weathering ranging from 110 to 270 ky. Such long periods confirm that during their transfer in the plains, the sediments are temporarily trapped at several places in the basins. In the Ganges and Brahmaputra rivers, the time-scales of sedimentary transfer are 575 and 160 ky, respectively. These values, which are of the same order as their response times, are much longer than the timescales of the Quaternary climate oscillations. It confirms the buffering action of the asiatic alluvial plains for the high-frequency sediment flux variations in response to external forcing in the chain. The study of suspended materials suggests that their chemical compositions result from the mixing of coarse river sediments with fine particles from various locations in the basin which are affected by vegetation recycling. By contrast to coarse sediments, the time-scales of transfer for the suspended materials are fast, e.g. a few ky, pointing the potential of U-series nuclides to assess particle transport laws as a function of their size. (author)

  3. Etude expérimentale sur le comportement d’un nouveau type d’accumulateur d’énergie thermique. Déterminations préliminaires sur l’installation expérimentale

    Directory of Open Access Journals (Sweden)

    Valentin Pavel

    2004-01-01

    Full Text Available On présente la première partie d’une étude concernant le comportement d’un nouveau type d’accumulateur d’énergie thermique. Sont présentées les déterminations se référant au comportement de l’unité centrale de stockage dans la phase de relaxation (refroidissement libre afin d’établir les pertes de chaleur, pour avoir une approche correcte des phénomènes dans les étapes ultérieures des études concernant l’accumulateur.

  4. Examen critique de la théorie de Lawrence Kohlberg du développement de la conscience morale et de l' attitude envers le comportement moral

    Directory of Open Access Journals (Sweden)

    Čabarkapa Milanko

    2009-01-01

    Full Text Available (francuski La relation da le conscience morale et du comportement moral est une des questions théoriques et pratiques traitées pendant une longue période mais qui, de nos jours, font l' objet de recherche de nombreux philosophes, théologiens, sociologues et psychologues. Une contribution particulière y a été apportée par Lawrence Kohlberg et sa théorie des stades de développement de la conscience morale et de l' attitude envers le comportement moral. Sa théorie peut être rangée parmi les théories à l' orientation cognitive qui occupent aujourd' hui une place prépondérante dans l' explication du comportement humain. Dans le cadre de cette théorie le développement de la conscience morale ou de la connaissance morale est considéré en relation avec le développement des aptitudes cognitives, ce développement se déroulant en plusieurs stades ou niveaux à travers les étapes de la vie humaine. Kohlberg distingue trois niveaux principaux du développement de la conscience morale: 1. un niveau préconventiel - où le moral se lie à l' autorité morale externe qui est la source de la peur ou de la peine; 2. Un niveau conventionnel - où la source de la morale est dans la réciprocité établie dans le cadre de la communication interpersonnelle, des relations sociales et des normes acceptées dans la société; 3. niveau post-conventiel - où la personne construit et accepte les principes universels de justice et les plus hautes valeurs humaines qui s' appliquent à l' ensemble de l' humanité. Dans le cadre de la théorie de Kohlberg une importance théorique et pratique est attribuée à l' analyse des conditions et des facteurs psychologiques permettant une transition de la conscience morale au comportement moral (le raisonnement moral, la prise de décisions, la prise de responsabilité, de même qu' à l' analyse de la quasi-obligation et d' autres circonstances qui empêchent cette transition. Les psychologues estiment que

  5. Le besoin de réassurance : de la psychologie au comportement du consommateur Une investigation théorique appliquée au cas de la consommation alimentaire moderne

    Directory of Open Access Journals (Sweden)

    Wejdene Yanhui

    2015-03-01

    Ce travail, dont l’intérêt est essentiellement théorique, s’inscrit parmi les travaux rares introduisant le besoin de réassurance dans l’étude du comportement du consommateur. Des travaux futurs peuvent se baser sur cette conceptualisation pour identifier les déterminants de ce besoin.

  6. Comportement mécanique des cavités dans le sel. Etat actuel de nos connaissances Mechanical Behaviour of Salt Cavities. Present State of Our Knowledge

    Directory of Open Access Journals (Sweden)

    Boucly P.

    2006-11-01

    Full Text Available L'utilisation depuis dix ans des premières cavités salines créées sur le site de Tersanne s'est accompagnée d'une réduction de leur volume relativement importante. Cette observation a conduit le Gaz de France à développer d'importantes études sur le comportement rhéologique du sel dans lequel sont creusées les cavités. Ces études, effectuées en collaboration avec des laboratoires universitaires, ont consisté en de nombreux essais en laboratoire (essais de longue durée à la température des terrains visant à déterminer les lois de comportement du matériau. Parallèlement, des modèles de calcul de divers degrés de complexité ont été élaborés afin de prendre en compte ces lois dans l'estimation de la stabilité et de la tenue à long terme de la cavité. Ces études ont abouti récemment à la mise au point d'un premier modèle de comportement du sel qui rend compte de l'ensemble des observations effectuées à ce jour sur les cavités. Grâce à ce modèle, il est maintenant possible d'étudier quelle influence a sur leur volume un type d'utilisation donné des cavités. The exploitation over the last ten years of the first salt cavities created in the Tersanne area has resulted in a relatively large decrease in their volume. This observation led Gaz de France to do extensive research on the rheological behavior of the salt into which cavities are leached. This research, performed in cooperation with university laboratories, consisted of numerous laboratory tests (long-duration tests at formation temperatures to determine the behavior laws of the material. At the same time, models for computing different degrees of complexity were developed to take these laws into account in evaluating the stability and long-term resistance of the cavity. This research has recently resulted in the development of an initial salt-behavior model involving all the observations made concerning these cavities to date. This model can now be

  7. Premiers resultats experimentaux sur le comportement de Tabebuia heterophylla (DC) Britton et de Hymenaea courbaril L. vis-a vis de la secheresse

    OpenAIRE

    Huc, Roland

    1985-01-01

    Deux espèces de la forêt de basse altitude d’Amérique tropicale (Antilles), Tabebebuia heterophylla (poirier-pays) et Hymenaea courbaril (courbaril), se révèlent intéressantes pour le reboisement des régions les moins arrosées. Le comportement de ces espèces vis-à-vis de la sécheresse est étudié grâce à un traitement sous forme d’arrosage différencié appliqué à des jeunes plants âgés de 1 an, en pépinière. L'évolution de l’état hydrique des plants est suivie au cours de 6 mois d’expéri...

  8. Comportement micromécanique d'un verre métallique Fe-B-Si-C chargé en hydrogène

    OpenAIRE

    Allemand , J.P.; Fouquet , F.; Perez , J.

    1986-01-01

    Les verres métalliques ferromagnétiques et magnétostrictifs soumis à une contrainte cyclique sont le siège d'un effet magnétoélastique, ou effet Δ E. En frottement intérieur, cet effet se caractérise par un amortissement d'ordre magnétomécanique. Ce comportement micromécanique a été suivi dans le cas d'un verre métallique base fer (Fe83B14Si1,5C1,5) en relation avec l'état structural du matériau. Par ailleurs, le chargement en hydrogène par voie électrolytique sur un tel matériau entraîne la ...

  9. ÉTUDE EXPÉRIMENTALE DES COMPORTEMENTS DE CIVELLES D’ANGUILLA ANGUILLA L. INFLUENCE DE LA DENSITÉ ET DE LA DISPONIBILITÉ EN ABRIS

    Directory of Open Access Journals (Sweden)

    BARDONNET A.

    2005-10-01

    Full Text Available Les comportements d’émigration et d’utilisation de l’espace développés par des civelles ont été observés dans des bacs et plans d’eau expérimentaux. Dans les bacs accueillant 55 ind./m2 sans possibilité d’émigration, la densité d’abris végétaux a été contrôlée (densités d’abris basse, 2 tiges de végétation artificielle par bac ou haute, 9 tiges par bac et le suivi a duré 2 mois et demi. Dans les plans d’eau ouverts, la densité de civelles introduites a été définie selon plusieurs modalités (1,6 - 6 - 9 et 12 ind./m2 et le suivi a duré 1 mois et demi. En bacs, après une période de 5 à 6 jours, les abris sont fortement recherchés pendant environ 6 semaines, les individus montrant alors une forte grégarité. Cette dernière disparaît ensuite, les abris sont alors moins recherchés et des comportements agressifs font leur apparition. En plans d’eau, les sorties concernent en moyenne 17 % du stock initial (mini = 7 %, maxi = 35 %, interviennent rapidement et sont presque toutes dirigées vers l’amont. Leur intensité ne dépend pas de la densité initiale et apparaît plus importante dans les bassins sans herbier. Les tailles et poids moyens des émigrants sont plus importants que ceux du lot initial. Au terme du suivi, la croissance apparaît forte, hétérogène et associée à une faible survie dans les plans d’eau peu ou moyennement alevinés. Elle apparaît plus faible, homogène et associée à une bonne survie dans les bassins à forte densité initiale. Ces observations sont compatibles avec l’expression d’un comportement grégaire en condition de densité importante, comportement favorisant une croissance homogène, ayant pour conséquence de retarder l’apparition d’actes agressifs. Au contraire, dans des contextes de faible densité, l’expression rapide du potentiel de croissance de quelques individus favoriserait l’apparition d’actes agressifs.

  10. Etude expérimentale et méthodologique sur le comportement des écrans de soutènement

    OpenAIRE

    MARTEN, Sonja; DELATTRE, Luc; MAGNAN, Jean Pierre

    2005-01-01

    Dans le domaine de la géotechnique, qui est caractérisé par la construction d'ouvrages uniques adaptés à un problème spécifique dans un terrain connu uniquement par prélèvements isolés, il est important pour le développement des méthodes de calcul d'étudier le comportement de ces ouvrages et de leur environnement. Les informations recueillies permettent - à condition qu'elles soient mises à disposition du public compétent - d'identifier les facteurs ayant une influence déterminante sur les ou...

  11. Influence de la nature des granulats sur le comportement rhéologique du béton à hautes temperatures

    Directory of Open Access Journals (Sweden)

    El abidine Rahmouni Zine

    2014-04-01

    Full Text Available Le béton est largement utilisé comme matériau de structure dans les ouvrages de génie civil tels que les tunnels. La prise en compte du comportement du béton soumis à des températures élevées est apparue dernièrement comme un problème majeur. Cette problématique concerne aussi bien des situations de service dans le cas des structures de stockage de déchets radioactifs que des situations d’accident, mises en exergue par les cas récents d’incendie dans des tunnels. Ce travail de recherche basé sur une approche expérimentale, analyse l’influence de la nature des granulats sur le comportement thermo-mécanique du béton soumis à une température élevée. Des bétons formulés avec deux granulats (calcaire concassé et silico-calcaire subissent des cycles de chauffage/refroidissement à une vitesse de 10°C/min à 200 °C, 400 °C et 900 °C. Nous étudions l’évolution de la fissuration, des propriétés thermiques, physiques et mécaniques des bétons en fonction des températures appliquées. Pour la nature de granulat siliceux, le silex présente une instabilité thermique se traduisant par un éclatement à partir de 300°C alors que le granulat calcaire présente aussi une instabilité à cause des phénomènes de décarbonatation/hydratation mais seulement pour le cycle de chauffage/refroidissement à 750°C.

  12. Le comportement mécanique des risers. Influence des principaux paramètres Mechanical Behaviour of Marine Risers Mode of Influence of Principal Parameters

    Directory of Open Access Journals (Sweden)

    Sparks C.

    2006-11-01

    Full Text Available Cet article a pour but de déterminer les principaux paramètres qui gouvernent le comportement mécanique des risers de forage et de production, et d'expliquer pourquoi et comment ils interviennent. Une compréhension claire de ces influences permet d'optimiser rapidement un riser donné sans avoir recours à un grand nombre d'analyses par ordinateur. Celui qui conçoit un riser est principalement préoccupé par les points suivants : - niveaux de contraintes dans la partie courante du riser ; - mouvements angulaires à la base du riser (ou moments, dans le cas d'une liaison rigide ; - mouvements relatifs au niveau de la liaison plate-forme/riser. La méthode utilisée dans cet article consiste à établir des expressions analytiques valables pour des risers simplifiés. Les conclusions tirées de ces expressions ont ensuite été verifiéés à l'aide d'un programme de calcul capable de simuler le comportement dynamique d'un riser dans des configurations variées. This paper attempts to identify the principal parameters, that influence the behavior of drilling and production risers and to explain how and why they do so. Clear understanding of these influences enable particular risers to be optimised rapidly without recourse to an inordinate number of computer analyses. The points of greatest concern, to the riser designer, are: a Stress levels in the main length of riser. (b Angular movement at sea bed (or moment, if the connection is rigid. (c Relative movement at riser/platform connection. The approach, used in the paper, has been ta derive analytical expressions, for simplified riser cases. Conclusions drawn from these expressions have then been checked for validity, by using a dynamic analysis computer program to simulate a wide range of cases.

  13. Comportement des poteaux composites en profils creux en acier remplis de béton Behavior of composite columns in hollow steel section filled with concrete

    Directory of Open Access Journals (Sweden)

    Othmani N.

    2012-09-01

    Full Text Available Le but de cet article, est la determination des rigidites flexionnelles EIx et EIy d’fune section mixte acier beton et plus precisement d’fun poteau en tube d’facier de section rectangulaire, remplie de beton, sollicitee a la flexion bi-axiale (N, Mx et My. L’festimation des rigidites sera faite a partir d’fune approche theorique par une analyse du poteau en elements finis (element barre a 4 degres de liberte, basee sur les conditions d’fequilibres a mi-portee en utilisant la relation moment-courbure (M–Φ de l’felement deforme par application de l’fequation suivante: EI=M/Φ. Le comportement des materiaux est celui comme adopte par les reglements Eurocode 2 et 3, respectivement pour le beton et l’facier. Afin de valider l’fapproche theorique utilisee dans cette etude, deux comparaisons ont ete faites : une premiere permettant de comparer les resultats des rigidites determinees par les relations moments courbures et celles calculees par l’fEurocode 4 et une deuxieme comparaison entre les charges de ruines de deux poteaux de grandeurs natures avec ceux testes au laboratoire [2]. Au vu des resultats obtenus, nous pouvons conclure que l’approche théorique utilisée dans cette étude ainsi que les modèles de comportement des matériaux sont adéquats pour ce genre de problèmes. The purpose of this paper is the determination of flexural stiffness EIx and EIy of a concrete filled rectangular cross section of a composite steel column, under biaxial bending (N, Mx and My. The rigidities will be estimated from a theoretical approach using a finite element analysis (element bar with 4 degrees of freedom, based on the equilibrium conditions at mid-span using the moment-curvature relationships (M–Φ of the deformed element by applying the following equation: EI=M/Φ. The material behavior is the one adopted by Eurocode 2 and 3, respectively, for concrete and steel. To validate the theoretical approach used, two comparisons

  14. Profils de multiples comportements à risque pour la santé des étudiants universitaires et leurs liens avec la santé mentale : utilisation de l’analyse des classes latentes

    Directory of Open Access Journals (Sweden)

    M. Y. Kwan

    2016-01-01

    Full Text Available Introduction : Les campus universitaires et collégiaux sont sans doute les derniers milieux au sein desquels il est possible d’aborder de façon globale la question de la santé d’une grande proportion de la population de jeunes adultes. Il est important que les promoteurs de la santé saisissent en quoi consistent les difficultés collectives auxquelles font face les étudiants et qu’ils comprennent mieux les modèles plus larges de comportements liés au mode de vie qui se manifestent au cours de cette période de la vie. L’objectif de notre étude a été de déterminer des catégories de comportements à risque pour la santé modifiables et d’étudier la relation entre ces catégories et divers paramètres relevant de la santé mentale au sein d’un vaste échantillon d’étudiants universitaires canadiens. Méthodologie : Des étudiants de premier cycle (n = 837, âge moyen = 21 ans de l’Université de Toronto ont répondu à l’enquête National College Health Assessment (NCHA (évaluation nationale de la santé dans les collèges qui comprend environ 300 éléments, dont des évaluations de l’état de santé, de la santé mentale et des comportements à risque pour la santé des étudiants. Nous avons réalisé une analyse des classes latentes pour relever des profils en fonction de huit comportements à risque pour la santé connus (consommation de marijuana, consommation d'autres drogues illégales, rapports sexuels à risque, tabagisme, excès occasionnel d’alcool, mauvaise alimentation, inactivité physique, manque de sommeil. Résultats : Nous avons obtenu un modèle à trois catégories axé sur les profils de comportement des étudiants : étudiants « typiques », « à risque élevé » et « relativement en bonne santé ». Nos résultats ont par ailleurs montré que les étudiants à risque élevé ont déclaré souffrir d’un niveau de stress considérablement plus élevé que celui des étudiants typiques

  15. Une piste pour la recherche de la "valeur centrale optimale". Discussion autour de la robustesse et du comportement de la "médienne", combinaison de normes Lp

    Directory of Open Access Journals (Sweden)

    Didier Josselin

    2004-08-01

    Full Text Available Dans cet article, nous présentons nos recherches autour de la médienne, estimateur robuste de valeur centrale. Nous discutons dans un premier temps la notion de centralité. Puis nous décortiquons la médienne, construite pour des buts de filtrage spatial en combinant la moyenne et la médiane à l’aide d’un bootstrap. Malgré son efficacité démontrée, la médienne est mise à l’épreuve de distributions statistiques particulières, mais courantes en analyse spatiale. Nous étudions son comportement en lien avec la valeur p des normes Lp et concluons sur une discussion et des pistes de recherche pour la quête du « point central optimal ». Cet article méthodologique complète celui publié précédemment dans Cybergéo, où la médienne était présentée davantage sous ses aspects (mathématiques (Josselin & Ladiray, 2002a.

  16. Qualité de l’information financière et comportement d’investissement: Cas des entreprises tunisiennes cotées

    Directory of Open Access Journals (Sweden)

    Asma Houcine

    2014-09-01

    Full Text Available L’objectif de cet article est d’étudier l’impact de la qualité de l’information financière sur le comportement d’investissement des entreprises. Nous appréhendons les caractéristiques du contexte tunisien grâce à une étude empirique de 25 entreprises cotées en bourse sur la période 1997-2009. Les constatations confirment que certaines caractéristiques de l’information financière, à savoir la fiabilité, accroissent l’inefficience de la décision d’investissement, tandis que d’autres, en l’occurrence le conservatisme, s’avèrent n’avoir aucun effet significatif. Nous attribuons de pareils résultats principalement aux spécificités contextuelles de l’environnement tunisien, notamment le cadre institutionnel, les réalités culturelles et les caractéristiques du système de gouvernance des entreprises.

  17. Generalities on the dynamic behaviour of rapid reactors. Preliminary studies on Rapsodie; Generalites sur le comportement dynamique des piles rapides. Etudes preliminaires de rapsodie

    Energy Technology Data Exchange (ETDEWEB)

    Campan, J.L.; Chaumont, J.P.; Clauzon, P.P.; Ghesquiere, G.; Leduc, J.; Schmitt, A.P.; Zaleski, C.P. [Commissariat a l' Energie Atomique, Cadarache (France). Centre d' Etudes Nucleaires

    1963-07-01

    The study of the dynamic behaviour of fast reactors may be divided into three section: 1. Stability studies around equilibrium power only the linear case was examining. S. Transient studies in the case of usual reactor operation (shut down, scram, etc.) with thermal shocks evaluation, for instance. 3. Explosion studies, for the maximum credible accidents. This report presents the status of the studies performed at the 'Physics Research Department' at Cadarache. Methods used are detailed and illustrated with the results obtained on a preliminary metallic core of the Rapsodie Reactor. (authors) [French] Le comportement dynamique des piles rapides, se presente tout naturellement sous trois aspects: 1. Etude de stabilite autour d'un regime d'equilibre (nous nous sommes bornes ici au cas lineaire). 2. Etude de regimes transitoires lors des operations normales de pile (arret, arret d'urgence, etc.) avec evaluation des chocs thermiques par exemple. 3. Etude des regimes transitoires de caractere explosif lors des accidents les plus graves possibles. Ce rapport presente l'etat des etudes a la date du 20 decembre 1961 a la Section d'Etudes de Piles Rapides a CADARACHE. Les methodes employees ont ete detaillees et illustrees a partir des resultats obtenus sur une premiere version 'combustible metallique' de Rapsodie. (auteurs)

  18. Comportement du béton à l'eau de mer. Synthèse bibliographique Concrete Behavior in Marine Environment. a Review Paper

    Directory of Open Access Journals (Sweden)

    Lesage J.

    2006-11-01

    Full Text Available Depuis quelques années, dans l'élaboration de structures destinées à l'exploration et à l'exploitation des hydrocarbures en mer, le choix se porte parfois sur les structures en béton plutôt que sur les structures en acier, en particulier dans les zones difficiles de la mer du Nord. C'est pourquoi il nous a semblé intéressant de faire le point des connaissances actuelles sur le comportement du béton à l'eau de mer. Les problèmes les plus importants se situent au niveau de la zone de marnage, c'est-à-dire la zone où le béton est alternativement immergé. Ils sont de tous ordres : contraintes mécaniques avec érosion et cavitation, action capillaire de l'eau avec alternance d'humidification et de séchage, action du gel et du dégel. Les moyens de lutte ne manquent pas : constructions massives, voire surdimensionnées, résistant au choc, choix des formes, mise en aeuvre soignée d'un béton de qualité riche en ciment, correctement dosé en agrégats, dur, dense, compact, imperméable; introduction dans le béton d'un entraineur d'air pour diminuer les effets du gel. L'utilisation d'un ciment prise mer et le choix d'un rapport eau/ciment voisin de 0,45 sont hautement recommandés. Quant à la corrosion, elle concerne les structures en béton à tous les niveaux, aussi bien dans la zone immergée en continu que dans la zone alternativement immergée. L'attaque du béton par les sulfates contenus dans l'eau de mer conduit à la formation de sels de Candlot qui provoquent une dégradation du béton. Le remède consiste à limiter la teneur en aluminate tricalcique du ciment. L'attaque des aciers de renfort par les chlorures a fait l'objet de nombreuses études: la solution consiste surtout à protéger les aciers par galvanisation ou protection cathodique. D'une manière générale, le béton placé dans ce milieu agressif que constitue l'eau de mer subit des contraintes mécaniques et physicochimiques importantes, mais on sait en g

  19. Concerning the study of the irreversible magnetic behaviour of superconductivity; Contribution a l'etude du comportement magnetique irreversible des supraconducteurs

    Energy Technology Data Exchange (ETDEWEB)

    Kuhn, G. [Commissariat a l' Energie Atomique, Grenoble (France). Centre d' Etudes Nucleaires

    1965-03-01

    The influence of the presence of extended lattice defects on the magnetic behaviour has been studied for the case of type I superconductors, such as Re and Ta, and in a more quantitative manner for the type II superconductor niobium. In this case, measurements of the thermal conductivity have given an estimate of the relative concentration of lattice defects in each specimen. These measurements show that the larger the number of lattice defects, the more irreversible becomes the magnetization curve, and the larger becomes the values of the critical current, which is related by a simple model to the magnetization values. Finally, a study by transmission electron microscopy has confirmed on the one hand the diversity of the extended lattice defects and on the other hand has allowed the formulation of several hypothesis on their respective influence. [French] L'influence de la presence de defauts etendus sur le comportement magnetique a ete etudie pour des supraconducteurs de premiere espece, tels que le rhenium et le tantale, et plus quantitativement pour un supraconducteur de deuxieme espece, le niobium. Dans ce cas, des mesures de conductibilite thermique ont permis d'estimer la concentration relative des defauts du reseau dans chaque echantillon. Ces mesures montrent que plus les defauts du reseau sont nombreux, plus la courbe d'aimantation est irreversible, et plus les valeurs du courant critique, reliees par un modele simple aux valeurs de l'aimantation, sont elevees. Enfin une etude par microscopie electronique en transmission - a permis d'une part de constater la diversite des defauts etendus et d'autre part de formuler quelques hypotheses sur leurs influences respectives.

  20. Effet de la température de frittage sur le comportement mécanique et tribologique de l'alliage TiNi poreux

    Science.gov (United States)

    Kahloul, Latifa; Chadli, Hacene; Montagne, Alex; Iost, Alain; Hervas, Isabel; Labaiz, Mohamed

    2018-03-01

    Le frittage en phase solide des poudres élémentaires de titane et de nickel a été utilisé pour élaborer l'alliage TiNi poreux. Dans ce travail, on a étudié l'effet de la température de frittage sur les comportements mécanique, tribologique et électrochimique de cet alliage. L'analyse par la diffraction des rayons X, la microscopie électronique à balayage (MEB) et l'analyse EDS révèlent la formation de la phase TiNi majoritaire pour tous les échantillons frittés aux différentes températures. L'échantillon fritté à 950 °C présente une dureté élevée, un module d'Young et un taux d'usure plus faibles que celui fritté à 850 °C. Les techniques : polarisation à circuit ouvert, potentiodynamique, et spectroscopie d'impédance électrochimique ont été utilisées pour vérifier l'influence de la température de frittage sur les paramètres électrochimiques de l'alliage dans des conditions physiologiques reproduisant celles rencontrées dans le corps humain (phosphate buffered saline solution). Les résultats des investigations montrent que l'alliage TiNi poreux présente un caractère passif et la cinétique de corrosion dépend dans une large mesure de la porosité ainsi que de la température de frittage.

  1. Étude du comportement des PME/PMI suisses en matière d’adoption de système de gestion intégré : entre méconnaissance et satisfaction: Cahier de recherche

    OpenAIRE

    Equey Balzli, Catherine

    2007-01-01

    Dans un environnement de mondialisation, de nombreux auteurs affirment que les outils de gestion intégrés (ERP) sont indispensables aux PME/PMI. Quelle est la situation des PME/PMI en Suisse en matière d’adoption d’ERP et comment se comportent-elles? Quel est le profil de la PME/PMI suisse qui utilise un ERP ? Notre recherche est basée sur une approche empirique. L’analyse statistique des réponses de près de sept cents PME/PMI des secteurs secondaire et tertiaire de toute la Suisse dévoile de...

  2. Influence de la luminosité nocturne et de la turbidité sur le comportement vertical de migration de la civelle d'anguille (Anguilla anguilla L. dans l'estuaire de l'Adour

    Directory of Open Access Journals (Sweden)

    DE CASAMAJOR M. N.

    1999-07-01

    Compte tenu des observations effectuées, le schéma migratoire vertical de l'espèce peut être modélisé de la manière suivante : l'interaction entre la luminosité nocturne et la turbidité influence les déplacements de civelles dans la colonne d'eau en relation avec leur comportement lucifuge. Plus la lumière nocturne qui pénètre dans la colonne d'eau est importante et plus les civelles migrent en profondeur.

  3. Radiation protection philosophy alters

    International Nuclear Information System (INIS)

    Firmin, G.

    1977-01-01

    Two significant events that have taken place this year in the field of radiation protection are reported. New SI units have been proposed (and effectively adopted), and the ICRP has revised its recommendations. Changes of emphasis in the latest recommendations (ICRP Publication 26) imply an altered radiation protection philosophy, in particular the relation of dose limits to estimates of average risk, an altered view of the critical organ approach and a new attitude to genetic dose to the population. (author)

  4. Music and Alterity Processes

    Directory of Open Access Journals (Sweden)

    Josep Martí

    2014-10-01

    Full Text Available The concept of alterity constitutes an important issue in anthropological research and, therefore, in the study of musical practices, as well. Without it, we could hardly understand other kinds of music situated in different spaces and time from the observer. In order to effectively approach these musical practices, we have to develop strategies to help us reduce as much as possible that which distorts the vision of the other. However, beyond the strictly epistemological and methodological issues, the study of music cannot ignore the ethical question related to the manner in which Western thought has understood and treated the other: through a hierarchical and stereotypical type of thinking based on the condition of otherness. Throughout the article, different alterity procedures are presented and discussed, such as synecdochization, exoticization, undervaluation, overvaluation, misunderstanding and exclusion. Taking these different alterity strategies into account may help us to better understand how the musical other is constructed, used and ultimately instrumentalized.

  5. Stimuli de l'environnement, organes des sens et comportement des Monogènes juvéniles et adultes

    Directory of Open Access Journals (Sweden)

    KEARN G. C.

    1993-01-01

    Full Text Available Lorsque les larves de Monogènes (oncomiracidiums établissent leur premier contact avec l'hôte, cela correspond à un changement fondamental dans leur mode de vie. La disparition de quelques structures sensorielles et l'acquisition de nouvelles en témoignent ; mais il existe certainement d'autres types de changements encore inconnus au niveau du système nerveux. Le développement larvaire lui-même, à ce moment là, est initié par des facteurs eux aussi inconnus. Nos connaissances du rôle des facteurs de l'environnement sur la vie des stades parasites juvéniles et adultes sont très limitées. Chez Entobdella soleae, parasite cutané de la Sole, il existe une réponse comportementale au changement de concentration d'oxygène ; chez l'adulte d'Encotyllabe caballeroi, chez qui des yeux se développent chez les post-larves, une réponse nette à la lumière existe. Les yeux persistants que l'on trouve chez d'autres Monogènes adultes, doivent avoir un rôle plus subtil dans le comportement. Le courant d'eau peut influencer le choix du site de fixation ou le développement dissymétrique du hapteur chez les Polyopisthocotylea, mais chez Entobdella soleae, parasite cutané, c'est le premier contact, et non une réponse au courant d'eau qui est déterminant dans l'orientation, la locomotion et éventuellement la migration. Ce contact est aussi certainement important dans la locomotion de certains parasites branchiaux comme Tetraonchus monenteron. L'attraction par des phéromones n'a pas été démontrée chez les Monogènes et l'environnement turbulent de la plupart d'entre eux rend ce mode de communication peu adapté. Cependant, les relations particulières entre E. soleae et son hôte poisson plat procurent une situation où ce phénomène serait possible et avantageux. Bien que les hormones des hôtes apparaissent jouer un rôle dans la biologie de la reproduction des hématophages comme les Polystomes, la démonstration exp

  6. Comportement alimentaire au cours du changement d'habitat lié à l'émergence chez le saumon atlantique Salmo salar L. et la truite commune Salmo trutta L., en conditions semi-naturelles

    Directory of Open Access Journals (Sweden)

    VIGNES J. C.

    1995-04-01

    L'analyse simultanée du déroulement de l'émergence, du degré de résorption de la vésicule, de la croissance des larves et de leurs contenus stomacaux a permis de mettre en évidence que la prise alimentaire est postérieure à l'émergence et démarre, avec la perte de poids de l'alevin, avant la fin de la résorption de la vésicule pour les 2 espèces. Le comportement alimentaire est un peu plus précoce chez les truites. Chez les saumons, la capture des proies est précédée par une phase d'ingestion de débris végétaux liée au positionnement benthique des alevins.

  7. Comportement hydrique de deux plantes fourragères cultivées au Sénégal (Andropogon gayanus et Brachiara brizantha) en fonction des contraintes exercées par le milieu

    OpenAIRE

    Boyer, Jacques

    1986-01-01

    Au Sénégal, la culture de certaines graminées réputées à hauts rendements fourragers exige la maîtrise de l'alimentation en eau, distribuée à grands frais sous forme d'irrigation par aspersion. Dans ces conditions, la connaissance et l'établissement de leur comportement hydrique sont indispensables si l'on veut rentabiliser l'eau apportée. A Sangalkam (presqu'île du Cap Vert), plusieurs années d'observations ont pu montrer que la croissance saisonnière et les rendements en matière sèche étai...

  8. Modélisation numérique et analyse du comportement d'un écran de soutènement auto-stable avec fondation ancrée dans le sol soutenu

    OpenAIRE

    CHOGUEUR , AISSA ,; Zadjaoui , Abdeldjalil

    2015-01-01

    International audience; RÉSUMÉ. L'objet du présent travail porte sur la modélisation numérique et l'analyse du comportement d'un écran de soutènement autostable du type paroi moulée en béton armé, fiché dans le sable par la méthode du coefficient de réaction à l'aide du logiciel K-Réa  et par la méthode numérique aux éléments finis en utilisant le logiciel Plaxis 2D-v8.5. Pour les deux méthodes, on procède aux différentes simulations lorsque le sol soutenu est chargé d'une fondation. la pra...

  9. Age, revenu et comportements d'épargne des ménages : une analyse théorique et empirique sur la période 1978-2006

    OpenAIRE

    Antonin, Céline

    2009-01-01

    Au cours des cinquante dernières années, des modèles successifs ont été élaborés pour rendre compte du comportement d’épargne des ménages. Ces modèles diffèrent principalement par la longueur de l’horizon décisionnel : après avoir supposé une vision de court terme, l’horizon s’est progressivement élargi à la durée de vie du ménage, avant de devenir illimité ; on est ainsi passé du modèle myope keynésien, au modèle de cycle de vie, puis au modèle dynastique. Ces modèles ne sont pas exclusifs, ...

  10. Altered metabolism in cancer

    Directory of Open Access Journals (Sweden)

    Locasale Jason W

    2010-06-01

    Full Text Available Abstract Cancer cells have different metabolic requirements from their normal counterparts. Understanding the consequences of this differential metabolism requires a detailed understanding of glucose metabolism and its relation to energy production in cancer cells. A recent study in BMC Systems Biology by Vasquez et al. developed a mathematical model to assess some features of this altered metabolism. Here, we take a broader look at the regulation of energy metabolism in cancer cells, considering their anabolic as well as catabolic needs. See research article: http://www.biomedcentral.com/1752-0509/4/58/

  11. Study of the behaviour of artificial radioactive aerosols. Applications to some problems of atmospheric circulation (1963); Etude du comportement dcs aerosols radioactifs artificiels. Applications a quelques problemes de circulation atmospherique (1963)

    Energy Technology Data Exchange (ETDEWEB)

    Lambert, G. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1963-11-15

    The aim of this work, consists in the examination of the behaviour of radioactive aerosols produced in the atmosphere by nuclear explosions, in order to deduce the most general laws governing atmospheric circulation and diffusion. After having given a general table of the radioactive aerosols present the authors consider the validity and the precision of the measurement methods and the concentration of the aerosols at ground level and in the upper atmosphere, as well as their deposition on the ground. The existence is thus demonstrated of a tropospheric equatorial barrier and of discontinuous and seasonal aspects of stratosphere-troposphere transfers. The role is shown of precipitations and dry auto-filtration in the lower atmosphere cleaning processes. This work makes it possible to describe the general behaviour of dust from the stratosphere, and to improve the total radioactive contamination of the globe. (author) [French] L'objectif de ce travail consiste a examiner le comportement des aerosols radioactifs introduits dans l'atmosphere par les explosions nucleaires, pour en deduire les lois les plus generals de la circulation et diffusion atmospheriques. Apres avoir dresse un tableau d'ensemble des aerosols radioactifs presents, on examine la validite et la precision des methodes de mesure de leur concentration, au niveau du sol et en haute atmosphere, ainsi que de leur depot a la surface du sol. On met ainsi en evidence l'existence d'une barriere equatoriale tropospherique; l'aspect discontinu et saisonnier des transferts stratosphere-troposphere; le role des precipitations et de l'auto-filtration seche, dans les processus de nettoyage de la basse atmosphere. Ces etudes permettent de decrire le comportement general des poussieres d'origine stratospherique et d'ameliorer le bilan de la contamination radioactive du globe. (auteur)

  12. Influence d'un écran électrique en aval d'une usine hydroélectrique sur le comportement de remontée du saumon atlantique (Salmo salar

    Directory of Open Access Journals (Sweden)

    GOSSET C.

    1992-01-01

    Full Text Available Le comportement de remontée de sept saumons atlantiques a été observé en aval d'un écran électrique répulsif implanté dans le canal de fuite d'une usine hydroélectrique située sur la Nive à 20 km de la mer. Le suivi des saumons par la technique du radiopistage montre qu'ils ne restent pas bloqués en position d'attente devant l'écran et ne dévalent pas d'une façon importante après avoir subi l'effet du champ électrique. Bien qu'il existe une individualité très marquée dans les mouvements migratoires, il n'a pas été constaté de différence sensible entre le comportement des saumons repoussés par l'écran et ceux qui ont vagabondé dans la basse Nive sans avoir pénétré dans la zone d'action de l'écran. L'efficacité répulsive de l'écran a été confirmée. Par ailleurs, on a observé un ralentissement important de l'activité des saumons dans la basse Nive pendant la période estivale et des remontées rapides vers les zones de frayères lors des coups d'eau d'automne.

  13. Long-term behavior of glass-ceramic zirconolite; Etude du comportement a long terme des vitrocristallins a base de zirconolite

    Energy Technology Data Exchange (ETDEWEB)

    Martin, Ch

    2003-07-01

    This work is a part of the investigation of new containment matrices considered for specific conditioning of radionuclides after separation. The aim was to demonstrate the long-term aqueous corrosion resistance of the glass-ceramic zirconolite considered for the conditioning of plutonium and the minor actinides. This material is composed of crystals of zirconolite (CaZrTi{sub 2}O{sub 7}) dispersed in a residual vitreous phase. It appears that glass-ceramic zirconolite presents a better kinetic behavior than the nuclear glass R 7T7. This is mainly due to a more important rate decrease that occurs more rapidly, that induces a quantity of glass altered at least 10 times as small as for R 7T7 glass. This high slowdown of the alteration rate is attributed to the formation of an alteration film that has been the subject of a specific study. We have demonstrated that the rate decrease was controlled as for the R7T7 glass by the amorphous phase of the alteration film forming a diffusion barrier for reactive species. It seems that the porosity is not the single parameter that explains the protective effect of the gel. The main differences compared with R7T7 glass are that silicon does not control the alteration of the material and that the gel is composed of two distinct phases. We have in particular identified a dense phase enriched in titanium and neodymium that probably influences deeply the kinetics. (author)

  14. Altered Perspectives: Immersive Environments

    Science.gov (United States)

    Shipman, J. S.; Webley, P. W.

    2016-12-01

    Immersive environments provide an exciting experiential technology to visualize the natural world. Given the increasing accessibility of 360o cameras and virtual reality headsets we are now able to visualize artistic principles and scientific concepts in a fully immersive environment. The technology has become popular for photographers as well as designers, industry, educational groups, and museums. Here we show a sci-art perspective on the use of optics and light in the capture and manipulation of 360o images and video of geologic phenomena and cultural heritage sites in Alaska, England, and France. Additionally, we will generate intentionally altered perspectives to lend a surrealistic quality to the landscapes. Locations include the Catacombs of Paris, the Palace of Versailles, and the Northern Lights over Fairbanks, Alaska. Some 360o view cameras now use small portable dual lens technology extending beyond the 180o fish eye lens previously used, providing better coverage and image quality. Virtual reality headsets range in level of sophistication and cost, with the most affordable versions using smart phones and Google Cardboard viewers. The equipment used in this presentation includes a Ricoh Theta S spherical imaging camera. Here we will demonstrate the use of 360o imaging with attendees being able to be part of the immersive environment and experience our locations as if they were visiting themselves.

  15. Music alters visual perception.

    Science.gov (United States)

    Jolij, Jacob; Meurs, Maaike

    2011-04-21

    Visual perception is not a passive process: in order to efficiently process visual input, the brain actively uses previous knowledge (e.g., memory) and expectations about what the world should look like. However, perception is not only influenced by previous knowledge. Especially the perception of emotional stimuli is influenced by the emotional state of the observer. In other words, how we perceive the world does not only depend on what we know of the world, but also by how we feel. In this study, we further investigated the relation between mood and perception. We let observers do a difficult stimulus detection task, in which they had to detect schematic happy and sad faces embedded in noise. Mood was manipulated by means of music. We found that observers were more accurate in detecting faces congruent with their mood, corroborating earlier research. However, in trials in which no actual face was presented, observers made a significant number of false alarms. The content of these false alarms, or illusory percepts, was strongly influenced by the observers' mood. As illusory percepts are believed to reflect the content of internal representations that are employed by the brain during top-down processing of visual input, we conclude that top-down modulation of visual processing is not purely predictive in nature: mood, in this case manipulated by music, may also directly alter the way we perceive the world.

  16. Music alters visual perception.

    Directory of Open Access Journals (Sweden)

    Jacob Jolij

    Full Text Available BACKGROUND: Visual perception is not a passive process: in order to efficiently process visual input, the brain actively uses previous knowledge (e.g., memory and expectations about what the world should look like. However, perception is not only influenced by previous knowledge. Especially the perception of emotional stimuli is influenced by the emotional state of the observer. In other words, how we perceive the world does not only depend on what we know of the world, but also by how we feel. In this study, we further investigated the relation between mood and perception. METHODS AND FINDINGS: We let observers do a difficult stimulus detection task, in which they had to detect schematic happy and sad faces embedded in noise. Mood was manipulated by means of music. We found that observers were more accurate in detecting faces congruent with their mood, corroborating earlier research. However, in trials in which no actual face was presented, observers made a significant number of false alarms. The content of these false alarms, or illusory percepts, was strongly influenced by the observers' mood. CONCLUSIONS: As illusory percepts are believed to reflect the content of internal representations that are employed by the brain during top-down processing of visual input, we conclude that top-down modulation of visual processing is not purely predictive in nature: mood, in this case manipulated by music, may also directly alter the way we perceive the world.

  17. La cohérence des comportements professionnels et privés chez les viticulteurs biologiques alsaciens The Coherence of Professional and Private Behaviours among Alsatian Organic Winegrowers

    Directory of Open Access Journals (Sweden)

    Jean Nizet

    2011-02-01

    Full Text Available Cette contribution s’interroge sur la forte cohérence observée au niveau des comportements professionnels et privés d’un petit échantillon de viticulteurs alsaciens que nous avons interviewés longuement. On s’attache d’abord à décrire ces comportements et à identifier les principes à partir desquels les acteurs les justifient. On propose ensuite deux hypothèses susceptibles de rendre compte de la cohérence constatée. La première suggère que cette cohé­rence est en partie construite par le discours des interviewés. La seconde s’interroge sur les mécanismes de socialisation. Trois mécanismes sont iden­tifiés : les tensions identitaires que les personnes ressentent lorsqu’elles s’écar­tent des principes évoqués ; les contrôles, formels et surtout informels, qu’elles exercent les unes sur les autres ; la hiérarchie qui s’instaure dans le champ de la viticulture biologique, en raison précisément de la plus ou moins forte cohé­rence des comportements. On montre que ces mécanismes combinent leurs effets pour produire une socialisation puissante et uniforme, qui fait des viti­culteurs biologiques interviewés des individus beaucoup plus intégrés que ce que prédisent des théories sociologiques qui mettent en avant la diversité, ou encore l’éclatement de l’expérience de l’individu contemporain.This contribution looks at the strong level of coherence observed in the behaviours, both professional and private, of a small sample of Alsatian winegrowers whom we interviewed at length. First there is an attempt at describing these behaviours and identifying the principles by which the actors justify them. We then propose two hypotheses liable to account for the coherence observed. The first suggests that this coherence is in part constructed out of the speech of the interviewees. The second asks about the socialization mechanisms. Three mechanisms are identified : the identitary tensions these

  18. Genetic alteration in hepatocellular carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Yoo Chul; Kang, Tae Woong; Lee, Jin Oh [Korea Cancer Center Hospital of Korea Atomic Energy Research Institute, Seoul (Korea, Republic of)

    1994-12-01

    Cancer of stomach, colon and liver are a group of the most common cancer in Korea. However, results with current therapeutic modalities are still unsatisfactory. The intensive efforts have been made to understand basic pathogenesis and to find better therapeutic tools for the treatment of this miserable disease. We studied the alteration of tumor suppressor genes and oncogenes in hepatocellular carcinoma in Korea. We found that alteration of Rb gene, APC were 33 %, 13 % respectively. But alterations of oncogenes such as myc, ras and mdm2 were rarely found. Our results suggests that HBV may act as oncogenic role in hepatocarcinogenesis instead of oncogenes. 6 figs, 2 tabs. (Author).

  19. Comportements en matière de santé associés au bronzage artificiel d’après l’Enquête sur la santé des jeunes du Manitoba de 2012-2013

    Directory of Open Access Journals (Sweden)

    E. Harland

    2016-01-01

    Full Text Available Introduction : Bien que le bronzage artificiel cause le cancer, il demeure relativement courant chez les adolescents. Nous en savons peu sur les habitudes en matière de bronzage artificiel ainsi que sur la prévalence de ce dernier au Canada, et nous en savons encore moins sur les comportements associés. Cette étude se penche sur la prévalence du bronzage artificiel chez les adolescents du Manitoba ainsi que sur son association avec d’autres caractéristiques individuelles et comportements en matière de santé. Méthodologie : Nous avons effectué des analyses secondaires des données recueillies dans le cadre de l’Enquête sur la santé des jeunes du Manitoba (2012-2013 auprès d’élèves de la 7e à la 12e année (n = 64 174 et nous avons examiné les associations entre le bronzage artificiel (selon si les répondants avaient déjà utilisé des appareils de bronzage artificiel et 25 variables. Les variables présentant un lien statistiquement significatif avec le bronzage artificiel ont fait l’objet de tests pour déterminer toute colinéarité potentielle et elles ont été regroupées en fonction de la force de leurs associations. Pour chaque groupe de variables dont l’association avait une signification statistique, la variable ayant l’effet de plus grande ampleur sur le bronzage artificiel a été intégrée au modèle final de régression logistique. Des analyses séparées ont été réalisées pour les garçons et les filles afin de mieux comprendre les différences fondées sur le sexe, et les analyses ont été ajustées en fonction de l’âge. Résultats : Globalement, 4 % des garçons et 9 % des filles ont indiqué avoir eu recours au bronzage artificiel, et la prévalence augmentait avec l’âge. Les associations entre le bronzage artificiel et les autres variables étaient similaires chez les garçons et les filles. Les modèles de régression logistique binaire ont révélé que plusieurs variables pr

  20. Study of the local stability of a feedback control having rectifiers with a controlled grid; Etude de la stabilite locale d'un asservissement comportant des redresseurs a grille controlee

    Energy Technology Data Exchange (ETDEWEB)

    Katz, A

    1962-07-01

    The equivalence of a rectifier with a controlled grid and a sampled device is established. Then, the sampled servomechanism theory is applied to the study of the response and of the local stability of a feedback control having a rectifiers system charged by an inductance-resistance assembly, in the case of the permanent conduction. The case of a feedback control of the first order and then of the second order are studied. The expressions of the test and sampled responses with a sinusoidal input is given. (O.M.) [French] On etablit l'equivalence d'un redresseur a grille controlee et d'un dispositif echantillonne. On applique ensuite la theorie des servomecanismes echantillonnes a l'etude de la reponse et de la stabilite locale d'un asservissement comportant un systeme de redresseurs charges par un ensemble inductance-resistance, dans le cas de la conduction permanente. On etudie le cas d'un asservissement du premier, puis du second ordre. On indique egalement les expressions des reponses miree et echantillonnee a une entree sinusoidale. (auteur)

  1. Comportement des matériaux organiques vis-à-vis des carburants oxygénés The Behavior of Organic Materials with Regard to Oxygenated Fuels

    Directory of Open Access Journals (Sweden)

    Puisais M.

    2006-11-01

    Full Text Available Les incidences d'emploi des produits oxygénés dans les carburants ont été déterminées sur la tenue des principaux matériaux polymères utilisés dans les véhicules et les équipements de distribution. Des carburants renferment diverses teneurs en éthanol ou en méthanol, éventuellement en conjonction avec des co-solvants tels que le tertiobutanol ou un mélange acétonobutylique ont été examinés. Les méthodes d'essais appliquées ont permis de déterminer le comportement à long terme des matériaux au niveau de leur perméabilité, gonflement, vieillissement, fissuration sous contraintes, extraction et résistance à l'ozone. The effects of using oxygenated products in gasolines have been determined concerning the resistance of the leading polymer materials used in vehicles and distribution equipment. Fuels containing varying amounts of ethanol or methanol, possibly in conjunction with cosolvents such as tertiobutanol or a butanol-acetone mixture, have been examined. The test methods applied have determined the long-term behavior of materials with regard to their permeability, swelling, aging, stress cracking, extraction and ozone resistance.

  2. ETUDE EXPERIMENTALE DE L’INFLUENCE DE LA RIGIDITE STATIQUE DES TOURS SUR LE COMPORTEMENT A L’USURE DES PLAQUETTES EN CARBURE METALLIQUE «NUANCE P25 »

    Directory of Open Access Journals (Sweden)

    L BOULANOUAR

    2002-12-01

    Full Text Available Ce travail consiste à étudier expérimentalement l’influence de quelques machines-outils sur le comportement à l’usure des plaquettes en carbure métalliques. Les essais ont été réalisés dans des conditions opératoires proches de celles industrielles. Les machines-outils utilisées sont caractérisées par leurs rigidités. Le suivi de l’évolution de l’usure des plaquettes en fonction du temps (τ et des éléments du régime de coupe (v, f et d sur chaque machine a été établi conformément à la méthode de planification des expériences. Les résultats obtenus ont été traités, analysés et interprétés physiquement.

  3. Mise en place des premiers comportements et utilisation de l'habitat après l'émergence chez les salmonidés d'eau courante

    Directory of Open Access Journals (Sweden)

    HELAND M.

    1995-04-01

    Les travaux que nous avons réalisés ces dernières années sur différentes espèces comme la Truite commune (Salmo trutta, le Saumon atlantique (Salmo salar ou l'Ombre commun (Thymallus thymallus illustrent la variabilité des comportements de post-émergence, en réponse à des conditions environnementales diversifiées. Différentes formes de dispersion apparaissent en direction de l'aval ou des zones de bordure, ou encore à proximité immédiate de la zone de frayère vers des microhabitats plus ou moins benthiques adaptés à la taille et aux capacités de nage des différentes espèces. La présence de congénères influence cette microrépartition par compétition pour les meilleurs postes d'accès à la nourriture (dérive d'invertébrés. L'existence de prédateurs lors de l'émergence peut entraîner le retardement de celle-ci ou des réenfouissements dans les graviers après émergence, mais aussi une augmentation de la dévalaison.

  4. The long-term behavior of glasses for wastes containment purposes; Le comportement a long terme des verres pour le confinement des dechets

    Energy Technology Data Exchange (ETDEWEB)

    Gin, S. [Division de l' energie nucleaire, CEA Centre de Valrho-Marcoule (France)

    2010-07-01

    In the presence of water, nuclear glasses undergo reactions that may be attributed, in part, to the nature of the chemical bonds set up within the glass structure, and - as regards other reactions - owing to the properties of the solute species. The main reactions involved include ion exchanges, these chiefly involving alkali metals, weakly bonded as these are to the glass network, silicon hydrolysis-condensation reactions, resulting in the formation of a porous hydrated layer, gradually taking on a passivating role, along with the precipitation of crystallized secondary phases. At the temperatures of interest in the disposal context (25 - 90 C degrees), such secondary phases mainly involve clay minerals. Fundamental research studies, conducted to gain an understanding of the mechanisms involved, have highlighted the existence of a strong coupling, at the mesoscopic scale, between the aforementioned chemical reactions, and solute transport, the hydrated layer having the ability to take on a passivating role, as its porosity closes. A new model named GRAAL (for Glass Reactivity with Allowance for the Alteration Layer), includes an explicit description of the four chief alteration mechanisms acting on glass: formation of the passivating layer by glass hydration, diffusion of water across that layer, dissolution of that layer over its outside surface, and precipitation of crystallized secondary phases. The equations may either be solved analytically, for simple cases, or be integrated into a geochemical code, to cater for chemistry-transport couplings, and simulate complex systems

  5. On the pathologically altered pulmonary pattern

    International Nuclear Information System (INIS)

    Ginzburg, M.A.; Kinoshenko, Yu.T.

    1982-01-01

    The notions ''normal'' and ''pathologically altered pulmonary pattern'' are specified. A grouping of lung pattern alterations based on morphopathogenetic features is provided: blood and lymphatic vascular alterations, changes in the bronchi, lung stroma, and combined alterations. Radiologic appearance of the altered pulmonary pattern is classified in keeping with the basic principles of an X-ray shade examination. The terms, such as ''enriching'', ''strengthening'', ''deformation'', etc., used for describing the pathologically altered pulmonary pattern are defined

  6. The oscillatory behavior of heated channels: an analysis of the density effect. Part I. The mechanism (non linear analysis). Part II. The oscillations thresholds (linearized analysis); Sur le comportement oscillatoire de canaux chauffes. - Etude theorique de l'effet de densite. 1ere partie: le mecanisme (analyse non lineaire), 2eme partie: seuils d'oscillation (analyse lineaire)

    Energy Technology Data Exchange (ETDEWEB)

    Boure, J. [Commissariat a l' Energie Atomique, Centre d' Etudes Nucleaires de Grenoble, 38 (France)

    1967-07-01

    The problem of the oscillatory behavior of heated channels is presented in terms of delay-times and a density effect model is proposed to explain the behavior. The density effect is the consequence of the physical relationship between enthalpy and density of the fluid. In the first part non-linear equations are derived from the model in a dimensionless form. A description of the mechanism of oscillations is given, based on the analysis of the equations. An inventory of the governing parameters is established. At this point of the study, some facts in agreement with the experiments can be pointed out. In the second part the start of the oscillatory behavior of heated channels is studied in terms of the density effect. The threshold equations are derived, after linearization of the equations obtained in Part I. They can be solved rigorously by numerical methods to yield: -1) a relation between the describing parameters at the onset of oscillations, and -2) the frequency of the oscillations. By comparing the results predicted by the model to the experimental behavior of actual systems, the density effect is very often shown to be the actual cause of oscillatory behaviors. (author) [French] Premiere partie: mecanisme (equations non linearisees). On expose le probleme du comportement oscillatoire des canaux chauffes en mettant l'accent sur la presence de retards dans le systeme et on propose un modele a 'effet de densite' pour expliquer ce comportement. L'effet de densite est la consequence de la relation physique entre l'enthalpie et la masse volumique du fluide. Les equations non lineaires du schema mathematique correspondant sont etablies et mises sous forme adimensionnelle. L'analyse de ces equations conduit a une description du mecanisme des oscillations. On donne la liste des parametres dont depend le comportement du modele. A ce stade de l'etude, on peut deja relever dans ce comportement plusieurs faits conformes a l

  7. Inorganic Species Behaviour in Thermochemical Processes for Energy Biomass Valorisation Comportement des espèces inorganiques dans les procédés thermochimiques de valorisation énergétique de la biomasse

    Directory of Open Access Journals (Sweden)

    Froment K.

    2013-09-01

    ériaux de lits (en réacteurs à lits fluidisés, les canalisations et l’aval du procédé ne sont pas toujours bien connues. Ces sujets concernant le comportement des espèces inorganiques et les conséquences technologiques et économiques vont probablement prendre de l’importance dans un futur proche en raison de : la tension sur le marché du bois qui augmente ainsi que les prix : une solution est de remplacer cette ressource « noble et propre » qu’est le bois par une ressource plus riche en cendres, comme la paille, les cultures énergétiques dédiées, ou les déchets agricoles voire ménagers. La production de biogaz depuis des décharges de déchets est une bonne illustration de la valorisation de déchets. Aller plus loin dans l’utilisation de ces ressources (conversion thermochimique riches en cendres augmentera leur potentielle réutilisation mais également les difficultés techniques de manière importante! l’enrichissement des sols pour l’agriculture dépend aujourd’hui de la possibilité de réemploi des cendres de biomasse, auxquelles il faut ajouter des fertilisants artificiels. La question de comment réutiliser la matière inorganique de la biomasse après conversion thermochimique devient un sujet important. L’objectif est de présenter une synthèse des difficultés technologiques liées à la présence de ces espèces inorganiques (corrosion, bouchages, etc. : un résumé détaillé du comportement des espèces inorganiques de la biomasse dans les procédés thermiques sera donné, allant des espèces relâchées pendant le traitement de la biomasse jusqu’à la prévention et les solutions quand c’est possible. Les sujets suivants seront développés : inventaires des espèces inorganiques de différentes ressources ; synthèse de la spéciation des espèces inorganiques dans les divers procédés de conversion thermiques ; barrières technologiques à franchir pour des raisons économiques et améliorations technologiques des

  8. Systemic dystrophic alterations of skeleton

    International Nuclear Information System (INIS)

    Zedgenidze, G.A.; Kishkovskij, A.N.; Elashov, Yu.G.

    1984-01-01

    A roentgenologic picture of dystrophic alterations of bones following hard, acute and chronic infections diseases, distinct disorders of vitanium balance, diseases of endocrine system, disorder of metabolism and diet, long-term exogenous intoxications including medicinal is given. Distinct dystrophic disorders are characterized both by quantitative and qualitative deviations in physiological change of bones

  9. Art as Alterity in Education

    Science.gov (United States)

    Zhao, Guoping

    2014-01-01

    In education, art has often been perceived as entertainment and decoration and is the first subject to go when there are budget cuts or test-score pressures. Drawing on Emmanuel Lévinas's idea of the primacy of radical alterity that breaks the totality of our being, enables self-transformation and ethics, and ensures community as a totality…

  10. Peary, Verifiability, and Altered Data

    Science.gov (United States)

    Rawlins, Dennis

    1991-01-01

    Robert Peary's alleged 1909 sledge-achievement of the North Pole is critically examined for credibility and consistency, with respect to terrestrial magnetism, solar-altitude, drift, and written & eyewitness testimony. Several alterations of the record are detected, and the dubiousness of navigation without determining longitude is emphasized.

  11. Alteration and alterability of the anorthosite from Angola

    OpenAIRE

    Simão, J.; Silva, Z. C. G.

    2010-01-01

    Siliceous rocks are widely used as dimension stone but the last decades have registered an increase rate of their alteration when exposed to polluted environments. Anorthosites were treated by acidified solutions of HCl, HN03 and H2S04 simulating acid rain and the response was recorded through different experiments such as on the surface of the polished rock and on the surface of uncovered thin sections. The main components, plagioclase and olivine, both responded in similar ways to each acid...

  12. Chemosensory alterations and cancer therapies

    International Nuclear Information System (INIS)

    Bartoshuk, L.M.

    1990-01-01

    Taste and olfaction provide sensory information and sensory pleasure. Cancer therapies affect both. Chemotherapy has not been shown to produce dramatic losses of taste or smell, but systematic studies on various chemotherapeutic agents and types of cancer are lacking. Radiation therapy does produce clear losses of both taste and smell. Both chemotherapy and radiation therapy alter the pleasure produced by taste and smell through the formation of conditioned aversions. That is, foods consumed in proximity with the nausea of therapy come to be unpleasant. The impact of conditioned aversions can be diminished by providing a scapegoat food just before therapy. Alterations in foods may be beneficial to the cancer patient. Increasing the concentrations of flavor ingredients can compensate for sensory losses, and providing pureed foods that retain the cognitive integrity of a meal can benefit the patient who has chewing or swallowing problems

  13. Comportement des fondations et des ancrages de structures marines sous l'effet de sollicitations cycliques Behavior of Foundations and Anchors for Marine Structures under the Effect of Cyclic Stresses

    Directory of Open Access Journals (Sweden)

    Le Tirant P.

    2006-11-01

    Full Text Available L'exploration et l'exploitation des hydrocarbures en haute mer conduisent à la mise en place d'ouvrages fixes ou flottants de dimensions de plus en plus colos sales, par des profondeurs d'eau sans cesse croissantes, atteignant actuellement 200 à 300 mètres en production, un millier de mètres en exploration. Les fondations des ouvrages pétroliers de production comprennent essentiel-lement- les pieux ou groupes de pieux, battus ou forés; - les fondations superficielles à embase poids. Le comportement des fondations ou ancrages de structures sous l'action des sollicitations cycliques est étudié, en fonction de la nature des terrains, à partir - de mesures et d'observations sur des structures réelles; d'expérimentations sur des modèles en semi-grandeur ou de simulations sur modèles réduits. Les exemples donnés situent la diversité des problèmes rencontrés pour l'instal-lation des ouvrages en haute mer et! l'ampleur des travaux nécessaires pour décrire plus correctement les phénomènes d'intéraction sols-structures mannes sous l'effet des chargements cycliques et transitoires et, par suite, mieux optimiser le dimensionnement des fondations et des ancrages. Exploration and production of hydrocarbons in the high seas lead ta the installation of fixed or floating structures having more and more colossal sizes at constantly increasing water depths which now attain 200 ta 300 meters for production and 1000 meters for exploration. The foundations of ail production structures mainly consist of - pilings or groups of pilings, either driven or drilled; superficial gravity foundations the behovior of foundations or anchors for such structures under the effect of cyclic stresses is examined as a function of the nature of formations, on the basis of - measurements and observations on actual structures, experiments with semi-full-sized models or by simulations with scale models. The examples given illustrate the diversity of the problems

  14. Les réseaux d'enseignants – Quels sont les comportements rédactionnels des locuteurs ? What are editorial behaviors on French teachers networks?

    Directory of Open Access Journals (Sweden)

    Isabelle Quentin

    2012-10-01

    Full Text Available Depuis une dizaine d'années, des enseignants créent et animent, en dehors des stricts circuits institutionnels, des réseaux d'échanges professionnels en s'appuyant sur les technologies du web participatif. Encore peu étudiés, plusieurs de ces réseaux en ligne connaissent aujourd'hui une forte audience. Cet article a plus spécifiquement pour objet de proposer et de tester une méthode nous permettant de rendre compte des comportements rédactionnels des enseignants qui s'expriment sur les forums hébergés par ces réseaux professionnels. Notre corpus est composé de 91 fils de discussion publiés sur le forum du réseau Pédago2.0. Ce réseau professionnel rassemble près de 500 professeurs en histoire et géographie. La plupart d'entre eux sont fortement investis dans l'association Les Clionautes et peuvent être qualifiés d'enseignants innovants. L'analyse de données quantitatives ainsi que des messages publiés sur le forum Pédago2.0, nous ont permis de mettre en lumière différents modes implicites de fonctionnement que nous présentons dans cet article.Over the past decade, teachers have created and animated corporate networks based on technologies of the Web 2.0 outside the strict institutional hierarchy. Yet little studied, many of these online networks are now welcomed with great success. The aim of this article is to provide a framework enabling us to identify significant aspects of teachers' behavior when they talk on newsgroups hosted through these networks. We tested our framework on a corpus of 91 threads of discussion published on the Pédago2.0 newsgroup. This professional network gathers nearly 500 French history and geography teachers. Most of these teachers are deeply implicated in an association, Les Clionautes, and can be described as innovating teachers. Quantitative data and posted messages analysis allowed us to highlight some implicit functioning rules, which we are presenting in this article.

  15. Altering prolactin concentrations in sows.

    Science.gov (United States)

    Farmer, C

    2016-07-01

    Prolactin has a multiplicity of actions, but it is of particular importance in gestating and lactating animals. In sows, it is involved in the control of mammary development and also holds essential roles in the lactogenic and galactopoietic processes. Furthermore, low circulating concentrations of prolactin are associated with the agalactia syndrome. The crucial role of prolactin makes it important to understand the various factors that can alter its secretion. Regulation of prolactin secretion is largely under the negative control of dopamine, and dopamine agonists consistently decrease prolactin concentrations in sows. On the other hand, injections of dopamine antagonists can enhance circulating prolactin concentrations. Besides pharmacologic agents, many other factors can also alter prolactin concentrations in sows. The use of Chinese-derived breeds, for instance, leads to increased prolactin concentrations in lactating sows compared with standard European white breeds. Numerous husbandry and feeding practices also have a potential impact on prolactin concentrations in sows. Factors, such as provision of nest-building material prepartum, housing at farrowing, high ambient temperature, stress, transient weaning, exogenous thyrotropin-releasing factor, exogenous growth hormone-releasing factor, nursing frequency, prolonged photoperiod, fasting, increased protein and/or energy intake, altered energy sources, feeding high-fiber diets, sorghum ergot or plant extracts, were all studied with respect to their prolactinemic properties. Although some of these practices do indeed affect circulating prolactin concentrations, none leads to changes as drastic as those brought about by dopamine agonists or antagonists. It appears that the numerous factors regulating prolactin concentrations in sows are still not fully elucidated, and that studies to develop novel applicable ways of increasing prolactin concentrations in sows are warranted. Crown Copyright © 2015. Published

  16. Acid Sulfate Alteration on Mars

    Science.gov (United States)

    Ming, D. W.; Morris, R. V.

    2016-01-01

    A variety of mineralogical and geochemical indicators for aqueous alteration on Mars have been identified by a combination of surface and orbital robotic missions, telescopic observations, characterization of Martian meteorites, and laboratory and terrestrial analog studies. Acid sulfate alteration has been identified at all three landing sites visited by NASA rover missions (Spirit, Opportunity, and Curiosity). Spirit landed in Gusev crater in 2004 and discovered Fe-sulfates and materials that have been extensively leached by acid sulfate solutions. Opportunity landing on the plains of Meridiani Planum also in 2004 where the rover encountered large abundances of jarosite and hematite in sedimentary rocks. Curiosity landed in Gale crater in 2012 and has characterized fluvial, deltaic, and lacustrine sediments. Jarosite and hematite were discovered in some of the lacustrine sediments. The high elemental abundance of sulfur in surface materials is obvious evidence that sulfate has played a major role in aqueous processes at all landing sites on Mars. The sulfate-rich outcrop at Meridiani Planum has an SO3 content of up to 25 wt.%. The interiors of rocks and outcrops on the Columbia Hills within Gusev crater have up to 8 wt.% SO3. Soils at both sites generally have between 5 to 14 wt.% SO3, and several soils in Gusev crater contain around 30 wt.% SO3. After normalization of major element compositions to a SO3-free basis, the bulk compositions of these materials are basaltic, with a few exceptions in Gusev crater and in lacustrine mudstones in Gale crater. These observations suggest that materials encountered by the rovers were derived from basaltic precursors by acid sulfate alteration under nearly isochemical conditions (i.e., minimal leaching). There are several cases, however, where acid sulfate alteration minerals (jarosite and hematite) formed in open hydrologic systems, e.g., in Gale crater lacustrine mudstones. Several hypotheses have been suggested for the

  17. Methamphetamine Alters Brain Structures, Impairs Mental Flexibility

    Science.gov (United States)

    ... Methamphetamine Alters Brain Structures, Impairs Mental Flexibility Email Facebook Twitter March 20, 2014 A new study adds to the copious existing evidence that chronic exposure to addictive drugs alters the brain in ways that make ...

  18. Study of archaeological analogs for the validation of nuclear glass long-term behavior models; Etude d'analogues archeologiques pour la validation des modeles de comportement a long terme des verres nucleaires

    Energy Technology Data Exchange (ETDEWEB)

    Verney-Carron, A

    2008-10-15

    Fractured archaeological glass blocks collected from a shipwreck discovered in the Mediterranean Sea near Embiez Island (Var) were investigated because of their morphological analogy with vitrified nuclear waste and of a known and stable environment. These glasses are fractured due to a fast cooling after they were melted (like nuclear glass) and have been altered for 1800 years in seawater. This work results in the development and the validation of a geochemical model able to simulate the alteration of a fractured archaeological glass block over 1800 years. The kinetics associated with the different mechanisms (interdiffusion and dissolution) and the thermodynamic parameters of the model were determined by leaching experiments. The model implemented in HYTEC software was used to simulate crack alteration over 1800 years. The consistency between simulated alteration thicknesses and measured data on glass blocks validate the capacity of the model to predict long-term alteration. This model is able to account for the results from the characterization of crack network and its state of alteration. The cracks in the border zone are the most altered due to a fast renewal of the leaching solution, whereas internal cracks are thin because of complex interactions between glass alteration and transport of elements in solution (influence of initial crack aperture and of the crack sealing). The lowest alteration thicknesses, as well as their variability, can be explained. The analog behavior of archaeological and nuclear glasses from leaching experiments makes possible the transposition of the model to nuclear glass in geological repository. (author00.

  19. Thermal alteration of aquatic ecosystems

    International Nuclear Information System (INIS)

    Gibbons, J.W.; Sharitz, R.R.

    1974-01-01

    The studies summarized emphasize that heated effluents may function to enrich or to stress an ecosystem, depending upon the biological feature examined. However, the potential for negative impact on aquatic environments must not be underestimated. The ultimate consequences of the sometimes drastic alteration of behavior patterns and life-history phenomena in the surviving inhabitants of thermal areas have yet to be assessed. The relatively short time span of thermal field studies has not allowed thorough understanding of the biological chain reactions that may take place as physiological and genetic adjustments are made. Ensuing changes in species interactions, practically uninvestigated at this time, may create heretofore unsuspected ecosystem changes. Man's challenge for the future is to gain a more thorough comprehension of thermal ecology and to determine how waste heat may be used as an energy subsidy rather than a stress to aquatic systems. These and subsequent studies may assist in understanding how natural ecosystems respond to temperature elevation and will lead to the development of concepts and principles pertaining to thermally altered environmental systems. (U.S.)

  20. Circadian disorganization alters intestinal microbiota.

    Science.gov (United States)

    Voigt, Robin M; Forsyth, Christopher B; Green, Stefan J; Mutlu, Ece; Engen, Phillip; Vitaterna, Martha H; Turek, Fred W; Keshavarzian, Ali

    2014-01-01

    Intestinal dysbiosis and circadian rhythm disruption are associated with similar diseases including obesity, metabolic syndrome, and inflammatory bowel disease. Despite the overlap, the potential relationship between circadian disorganization and dysbiosis is unknown; thus, in the present study, a model of chronic circadian disruption was used to determine the impact on the intestinal microbiome. Male C57BL/6J mice underwent once weekly phase reversals of the light:dark cycle (i.e., circadian rhythm disrupted mice) to determine the impact of circadian rhythm disruption on the intestinal microbiome and were fed either standard chow or a high-fat, high-sugar diet to determine how diet influences circadian disruption-induced effects on the microbiome. Weekly phase reversals of the light:dark (LD) cycle did not alter the microbiome in mice fed standard chow; however, mice fed a high-fat, high-sugar diet in conjunction with phase shifts in the light:dark cycle had significantly altered microbiota. While it is yet to be established if some of the adverse effects associated with circadian disorganization in humans (e.g., shift workers, travelers moving across time zones, and in individuals with social jet lag) are mediated by dysbiosis, the current study demonstrates that circadian disorganization can impact the intestinal microbiota which may have implications for inflammatory diseases.

  1. Elaboration of an Elasto-Plastic Model for High Porosity Chalks. Application to the Compaction of Petroleum Reservoirs Elaboration d'un modèle de comportement élasto-plastique pour les craies très poreuses. Application à la compaction des réservoirs pétroliers

    Directory of Open Access Journals (Sweden)

    Shahrour I.

    2006-11-01

    Full Text Available This paper presents a study of the compaction of petroleum reservoirs applied to very porous carbonate rocks such as chalk. In production estimates made in reservoir engineering, the processing of the mechanical problem is often greatly simplified. Good modelling of how materials behave gives special consideration to the influence of mechanical deformations on fluid recovery. After an analysis of the mechanical behaviour of very porous chalks, an elastoplastic behaviour model is derived so as to reproduce the principal experimental observations. This behaviour model can then be used to perform local simulations of the mechanical behaviour of a reservoir under- going depletion and thus to demonstrate the importance of the stress path and the initial stress state on the deformation of materials and hence on the recovery rate. Dans les applications pétrolières, les études de la compaction des roches réservoirs interviennent dans l'estimation des quantités de fluide récupérables et de la subsidence induite par la déplétion du champ de production. Dans la première partie du travail, nous montrons qu'à partir de l'équation linéarisée de la conservation de la masse de fluide, il est possible d'exprimer un taux de récupération distinguant les contributions respectives du fluide et de la roche. En ingénierie de réservoirs, l'hypothèse d'un chemin de contrainte prépondérant dans le milieu de production permet d'exprimer la contribution de la déformation de la roche au moyen de la compressibilité volumique des pores selon ce chemin. Le taux de récupération obtenu est alors dépendant du chemin de contrainte. Lorsque le chemin de contrainte dans le réservoir n'est pas homogène, il est alors nécessaire de connaître la loi de comportement mécanique du matériau étudié. Dans le cas des carbonates très poreux, nous désirons montrer l'influence liée au choix du chemin de contrainte sur les estimations obtenues par une m

  2. Contributions of vitreous natural analogs to the investigation of long-term nuclear glass behavior; Apports des analogues naturels vitreux a la validation des codes de prediction du comportement a long terme des verres nucleaires

    Energy Technology Data Exchange (ETDEWEB)

    Techer, I

    1999-07-01

    This study assesses the extend of the analogy between the alteration behavior in water and in a moist clay environment of aluminosilicate volcanic glass and alumino-borosilicate nuclear containment glass. Basaltic glass alteration in water initially occurs by hydrolysis processes with an activation energy on the order of 73 kJ.mol{sup -1}. As the reaction progresses, the alteration rate drops by over four orders of magnitude from the initial rate r{sub 0}, The alteration kinetics are not governed by the alteration solution chemistry alone, the glass alteration film appears to have a major role as a diffusion barrier limiting the transfer of reaction species and products. All these aspects highlight the behavioral analogy between basaltic glass and nuclear borosilicate glass in aqueous media. Conversely, the alteration reaction of obsidian-type volcanic glass involves other mechanisms than those governing the dissolution of borosilicate glass. Basaltic glass alteration is also examined in the presence of a clay environmental material, in a study of the natural basaltic glass and argillaceous pelites system of the Salagou basin in southern France, in an approach combining mineralogical, chemical and isotopic data to assess the interactions between a basaltic glass and the argillaceous pelites. Laboratory leach test results with basaltic glass and measured data for the Salagou glass in its natural environment are modeled using a code implementing a kinetic law coupling diffusive transfer of dissolved silica with a reaction affinity law. (author)

  3. Epigenetic alterations underlying autoimmune diseases.

    Science.gov (United States)

    Aslani, Saeed; Mahmoudi, Mahdi; Karami, Jafar; Jamshidi, Ahmad Reza; Malekshahi, Zahra; Nicknam, Mohammad Hossein

    2016-01-01

    Recent breakthroughs in genetic explorations have extended our understanding through discovery of genetic patterns subjected to autoimmune diseases (AID). Genetics, on the contrary, has not answered all the conundrums to describe a comprehensive explanation of causal mechanisms of disease etiopathology with regard to the function of environment, sex, or aging. The other side of the coin, epigenetics which is defined by gene manifestation modification without DNA sequence alteration, reportedly has come in to provide new insights towards disease apprehension through bridging the genetics and environmental factors. New investigations in genetic and environmental contributing factors for autoimmunity provide new explanation whereby the interactions between genetic elements and epigenetic modifications signed by environmental agents may be responsible for autoimmune disease initiation and perpetuation. It is aimed through this article to review recent progress attempting to reveal how epigenetics associates with the pathogenesis of autoimmune diseases.

  4. Window to 'Clovis's' Altered Past

    Science.gov (United States)

    2004-01-01

    This image taken by the Mars Exploration Rover Spirit shows a rock outcrop dubbed 'Clovis.' The rock was discovered to be softer than other rocks studied so far at Gusev Crater after the rover easily ground a hole (center) into it with its rock abrasion tool. An analysis of the interior of the hole with the rover's alpha particle X-ray spectrometer found higher concentrations of sulfur, bromine and chlorine compared to basaltic, or volcanic, rocks at Gusev. This might indicate that Clovis was chemically altered, and that fluids once flowed through the rock depositing these elements. Spirit's solar panels can be seen in the foreground. This image was taken by the rover's navigation camera on sol 205 (July 31, 2004).

  5. Self-alteration in HRI

    DEFF Research Database (Denmark)

    Yamazaki, Ryuji; Nørskov, Marco

    Humanlike androids are being developed with the ambition to be immersed into our daily life and meet us on an equal level in social interaction. The possibilities and limitations of these types of robots can potentially change societies and Human-Robot Interaction might affect the very way in which...... and Denmark, we examine how Telenoid, a new type of teleoperated android robot designed as a minimalistic human, affect people in the real world. We introduce Telenoid to real-world as the fields of elderly care and child education by focusing on the social aspects of the android robot that might facilitate...... the ways in which our subjectivity can be innerly transformed, decentred, in other words, self-altered. In our trials so far, we have been investigating the potential of teleoperated androids, which are embodied telecommunication media with humanlike appearances. By conducting pilot studies in Japan...

  6. modelisation du comportement hydrologique du bassin versant

    African Journals Online (AJOL)

    LGE

    paramètres sont vérifiés sur la (s) période (s) de contrôle afin de s‟assurer que la modélisation n‟était pas ... critère est très utilisé en hydrologie pour évaluer les performances des modèles pluie-débit. .... Cela exprime la bonne performance et la meilleure applicabilité du modèle CEQUEAU au bassin versant du. Boubo.

  7. SIMULATION DU COMPORTEMENT DYNAMIQUE DU VOILIER

    OpenAIRE

    Roncin, Kostia

    2001-01-01

    National audience; A simulator of two sailing boats in interaction is being made in order to provide sportsmen with a reliable analytical tool. We presently describe different models we used. Stationary hydrodynamics efforts have been specially evaluated. Experiences plan method has been implemented to exploit the towing tank tests made in the Fluids Mechanic Laboratory of Ecole Centrale de Nantes. Here are set out partial results of the model we achieved. At last, a simulator example illustr...

  8. Lipides et comportement alimentaire chez les enfants

    Directory of Open Access Journals (Sweden)

    Nicklaus Sophie

    2016-05-01

    Full Text Available Cet article analyse la place des lipides dans l’alimentation des jeunes enfants. Premièrement, il montre d’une part la contribution importante que devraient avoir les lipides aux apports énergétiques totaux des enfants de moins de deux ans, en raison de leur intérêt fonctionnel dans le développement neuronal et de leur effet potentiellement protecteur d’une obésité ultérieure; d’autre part, il souligne la faible contribution des lipides aux apports énergétiques totaux chez les enfants français, d’après les estimations disponibles, avec une minorité d’enfants pour lesquels les apports en lipides sont satisfaisants. Deuxièmement, il rapporte les connaissances disponibles concernant le contrôle « sensoriel » de la consommation de lipides. Chez les nouveau-nés et les nourrissons, quelques travaux portent sur les préférences pour les lipides, et indiquent l’absence d’une préférence pour les lipides. Chez les enfants, une teneur augmentée en lipides a parfois (mais pas toujours un effet positif sur l’appréciation d’un aliment, avec souvent une teneur optimale; mais elle n’est pas associée à une consommation plus élevée de l’aliment. Des teneurs élevées en lipides ont deux effets sur les apprentissages alimentaires. Chez des enfants de moins de 3 ans, un triplement de la densité énergétique par l’ajout de lipides est associé à la mise en place d’un rassasiement conditionné pour l’aliment concerné; chez des enfants plus âgés, un doublement de la densité énergétique par l’ajout de lipides, est associé à une augmentation de l’appréciation des flaveurs associées aux versions les plus riches en lipides. Des pistes d’études complémentaires sont discutées.

  9. Contribution to the study of the geophysical behaviour of lead-210 by application of alpha spectrometry; Contribution a l'etude du comportement geophysique du plomb 210 par application de la spectrometrie alpha

    Energy Technology Data Exchange (ETDEWEB)

    Nezami, M. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1965-06-01

    comportement geophysique du plomb 210 sont les suivants: - la teneur mensuelle en plomb 210 et en polonium 210 dans les eaux de pluie est a peu pres constante en fonction du temps. - dans la region de Gif-sur-Yvette, le nettoyage par 'retombee seche' peut atteindre 40 a 50 pour cent de la retombee totale. - une etude sur des carottes de glace de l'Antarctique permet de determiner un taux annuel d'accumulation equivalent a 13.8 cm d'eau et de mettre en evidence des anomalies de concentration periodiques en concordance avec les derniers maximums d'activite solaire. - un bilan est etabli entre le degagement de radon des continents et les retombees de plomb 210. (auteur)

  10. Progrès récents de la connaissance du comportement mécanique des cavités salines Recent Progress in Understanding the Mechanical Behavior of Salt Cavities

    Directory of Open Access Journals (Sweden)

    Fauveau M.

    2006-11-01

    Full Text Available La diminution de volume des cavités salines exploitées à Tersanne depuis quinze ans a conduit le Gaz de France à développer des études sur la rhéologie du sel en collaboration avec des laboratoires universitaires. Ces études ont abouti à la mise au point d'un modèle rhéologique rendant compte des observations effectuées in situ. Simultanément ont été développés, en collaboration avec l'École Nationale Supérieure des Mines de Paris, des modèles numériques qui permettent d'effectuer des simulations du comportement mécanique des cavités. Le plus performant de ces modèles est le code VIPLEF. Validé par une confrontation avec des solutions analytiques et la simulation d'un cas réel (cavité TE O2 de Tersanne, ce programme a permis d'étudier l'influence de la forme d'une cavité sur sa perte de volume et d'ébaucher un critère de choix de forme optimale . Les récentes études ont également permis de mettre en évidence les paramètres qui concourent à la remontée du fond des cavités (gravité, gradient géothermique, stratigraphie, forme de la cavité, etc. , grâce à l'utilisation de ce modèle. De nombreuses intuitions de physiciens ont pu être ainsi confirmées et approfondies par le calcul numérique. The reduction in the geometric volume of the salt cavities used for gas storage at Tersanne, France, for 15 years led Gaz de France to undertake research on the rheology of salt in cooperation with university laboratories. This research led to the development of a rheological model describing in situ observations. At the same time, in collaboration with the Ecole Nationale Supérieure des Mines in Paris, numerical models were developed for simulating the mechanical behavior of cavities. The most effective such model is the VIPLEF code. Checked by comparison with analytical solutions and by simulation of an actual case (TE O2 cavity at Tersanne, this program was used to study the influence of the shape of a cavity on

  11. Epigenetic Alterations in Parathyroid Cancers

    Directory of Open Access Journals (Sweden)

    Chiara Verdelli

    2017-02-01

    Full Text Available Parathyroid cancers (PCas are rare malignancies representing approximately 0.005% of all cancers. PCas are a rare cause of primary hyperparathyroidism, which is the third most common endocrine disease, mainly related to parathyroid benign tumors. About 90% of PCas are hormonally active hypersecreting parathormone (PTH; consequently patients present with complications of severe hypercalcemia. Pre-operative diagnosis is often difficult due to clinical features shared with benign parathyroid lesions. Surgery provides the current best chance of cure, though persistent or recurrent disease occurs in about 50% of patients with PCas. Somatic inactivating mutations of CDC73/HRPT2 gene, encoding parafibromin, are the most frequent genetic anomalies occurring in PCas. Recently, the aberrant DNA methylation signature and microRNA expression profile have been identified in PCas, providing evidence that parathyroid malignancies are distinct entities from parathyroid benign lesions, showing an epigenetic signature resembling some embryonic aspects. The present paper reviews data about epigenetic alterations in PCas, up to now limited to DNA methylation, chromatin regulators and microRNA profile.

  12. Le comportement de l'éleveur face au vêlage : approche comportementale par le biais d'un questionnaire d'opinion dans le cadre d'une enquête d'écopathologie sur l'infertilité des vaches allaitantes

    OpenAIRE

    Van de Wiele, Anne

    2004-01-01

    Une enquête a été menée par le Centre d'écopathologie Animale de 1987 à 1989, sur les "conditions de vêlage, facteurs de risque de l'infertilité des vaches allaitantes". Pour un facteur de risque particulier, le comportement de l'éleveur face au vêlage, c'est la technique du "questionnaire de structure d'opinion" qui a été choisie et adaptée pour l'élevage. Un entretien collectif d'éleveurs a permis de sélectionner les phrases, sur lesquelles chaque éleveur de l'enquête devait ensuite se posi...

  13. Altered mental status from acyclovir.

    Science.gov (United States)

    Martinez-Diaz, Gabriel J; Hsia, Renee

    2011-07-01

    Acyclovir is widely used in the treatment of herpes virus infections, particularly herpes simplex virus and varicella-zoster virus. Acyclovir, when given promptly upon the start of a herpes zoster eruption, speeds healing and diminishes acute pain. Because acyclovir is a commonly used medication, it is crucial for health providers to be aware of appropriate dosing as well as possible side effects. We present this case to increase awareness of the potential for inappropriate dosing of acyclovir and the presentations of patients with toxic effects. We report the case of a 65-year-old man with a past medical history significant for chronic kidney disease who presented to the Emergency Department with progressive confusion and ataxia over 2 days. Thorough questioning in the patient's native language revealed that he had recently started a medication for a "rash." Neither he nor his family knew the name of the new medication; further investigation revealed it to be acyclovir. Although other diagnoses were considered in the differential diagnosis for this patient with altered mental status, he was treated for presumed acyclovir toxicity and given prompt dialysis, upon which his symptoms resolved. It is important for physicians to remember that even common medications such as acyclovir can have serious side effects and complications. In this case, renal dosing was not used in a patient on hemodialysis. Acyclovir must be renally dosed and carefully monitored through drug level measurement in patients with limited kidney function to prevent serious side effects, such as the neurological sequelae demonstrated in this case report. Emergency physicians should be aware of the potential for inappropriate dosing of this medication and the presentations of patients with toxic effects. Copyright © 2011 Elsevier Inc. All rights reserved.

  14. Models for the Behavior of Offshore Structure Foundations. Part One: Methodologies and Rheological Models for Soils Modèles pour le comportement des fondations d'ouvrages types marins. Première partie : Méthodologies et modèles rhéologiques de sols

    Directory of Open Access Journals (Sweden)

    Meimon Y.

    2006-11-01

    structure. Prospects opened up by the research are discussed. La conception des fondations de grands ouvrages est une tâche complexe qui requiert à la fois l'expérience de l'expert et l'utilisation de modèles numériques adéquats pour assurer la sécurité et optimiser les coûts de dimensionnement. En fait, prévoir le comportement d'une fondation nécessite de bien évaluer les effets combinés de la technique de mise en place, de la variabilité spatiale des propriétés mécaniques, de l'incertitude sur les chargements et des techniques de modélisation du comportement mécanique des géomatériaux. Ceci est particulièrement vrai pour les plates-formes marines, qu'elles soient destinées à l'exploration ou à la production du pétrole, dans la mesure où les chargements non-monotones dus à l'environnement marin, souvent très sévère, peuvent avoir des effets très néfastes sur le comportement de ces structures. On présente, en deux parties, la synthèse d'une dizaine d'années d'activités de recherche, menées par une équipe de l'Institut Français du Pétrole (IFP, en collaboration avec plusieurs équipes universitaires et des centres techniques et industriels, pour la mise au point de méthodologies et d'outils adaptés au calcul du comportement des fondations d'ouvrages types marins durant toute la durée de vie de la plate-forme. Cet article concerne la première partie qui est dévolue à l'exposé des démarches développées et à la modélisation de l'état local des géomatériaux par des modèles rhéologiques. Démarches de modélisation du comportement des fondations d'ouvrages marins : On analyse d'abord la spécificité des fondations de plates-formes marines en insistant sur les différences avec les ouvrages à terre : dimension inusitée, chargement aléatoire par les éléments marins. On peut alors dégager plusieurs types de fondation (fig. 2. 1 et 2. 2 et les classes de problèmes qu'il est important d'étudier, qui recouvrent aussi

  15. Les formations volcano-sedimentaires de la marge de la Guadeloupe (Petites antilles): Etudes mineralogique et geochimique

    Digital Repository Service at National Institute of Oceanography (India)

    Mascarenhas, A

    include: sedimentological characteristics of cores from different morphostructural settings, petrochemical analyses of volcanic sands with the aim of a tephrochronological correlation, mineralogical analyses of pelitic fraction, geochemistry of elements...

  16. Do invasive plant species alter soil health?

    Science.gov (United States)

    Invasive species may alter soil characteristics or interact with the soil microbial community to yield a competitive advantage. Our objectives were to determine: if invasive plant species alter soil properties important to soil health; and the long-term effects of invasive plant species on soil pro...

  17. An Analysis of the Alteration Specialist Occupation.

    Science.gov (United States)

    Buerkel, Elaine; Rehling, Joseph H.

    The general purpose of the occupational analysis is to provide workable, basic information dealing with the many and varied duties performed in the textile service occupation. The industry needs properly trained alteration specialists, bushelmen and dressmakers, in the repairing, remodeling, altering or renovating of garments. Their personal…

  18. [Epigenetic alterations in acute lymphoblastic leukemia].

    Science.gov (United States)

    Navarrete-Meneses, María Del Pilar; Pérez-Vera, Patricia

    Acute lymphoblastic leukemia (ALL) is the most common childhood cancer. It is well-known that genetic alterations constitute the basis for the etiology of ALL. However, genetic abnormalities are not enough for the complete development of the disease, and additional alterations such as epigenetic modifications are required. Such alterations, like DNA methylation, histone modifications, and noncoding RNA regulation have been identified in ALL. DNA hypermethylation in promoter regions is one of the most frequent epigenetic modifications observed in ALL. This modification frequently leads to gene silencing in tumor suppressor genes, and in consequence, contributes to leukemogenesis. Alterations in histone remodeling proteins have also been detected in ALL, such as the overexpression of histone deacetylases enzymes, and alteration of acetyltransferases and methyltransferases. ALL also shows alteration in the expression of miRNAs, and in consequence, the modification in the expression of their target genes. All of these epigenetic modifications are key events in the malignant transformation since they lead to the deregulation of oncogenes as BLK, WNT5B and WISP1, and tumor suppressors such as FHIT, CDKN2A, CDKN2B, and TP53, which alter fundamental cellular processes and potentially lead to the development of ALL. Both genetic and epigenetic alterations contribute to the development and evolution of ALL. Copyright © 2017 Hospital Infantil de México Federico Gómez. Publicado por Masson Doyma México S.A. All rights reserved.

  19. Models for the Behavior of Offshore Structure Foundations. Part Two: Applications to Structural Design and Quality Assurance Processes Modèles pour le comportement des fondations d'ouvrages types marins. Deuxième partie : applications au calcul d'ouvrage et processus d'assurance qualité

    Directory of Open Access Journals (Sweden)

    Meimon Y.

    2006-11-01

    structure. Prospects opened up by the research are discussed. La conception des fondations de grands ouvrages est une tâche complexe qui requiert à la fois l'expérience de l'expert et l'utilisation de modèles numériques adéquats pour assurer la sécurité et optimiser les coûts de dimensionnement. En fait, prévoir le comportement d'une fondation nécessite de bien évaluer les effets combinés de la technique de mise en place, de la variabilité spatiale des propriétés mécaniques, de l'incertitude sur les chargements et des techniques de modélisation du comportement mécanique des géomatériaux. Ceci est particulièrement vrai pour les plates-formes marines, qu'elles soient destinées à l'exploration ou à la production du pétrole, dans la mesure où les chargements non-monotones dus à l'environnement marin, souvent très sévère, peuvent avoir des effets très néfastes sur le comportement de ces structures. On présente, en deux parties, la synthèse d'une dizaine d'années d'activités de recherche, menées par une équipe de l'Institut Français du Pétrole (IFP, en collaboration avec plusieurs équipes universitaires et des centres techniques et industriels, pour la mise au point de méthodologies et d'outils adaptés au calcul du comportement des fondations d'ouvrages types marins durant toute la durée de vie de la plate-forme. Cet article concerne la deuxième partie qui est dévolue à l'application des modèles développés au calcul d'ouvrage par la méthode des éléments finis et à l'exposé d'un processus de validation des modèles, étape d'une démarche d'assurance qualité. Méthodes pour le calcul des fondations marines : Le système de programmes FONDOF utilisant la méthode des éléments finis a été développé. Il comprend (fig. 1. 1 des interfaces interactives de mise en données et de dépouillement des résultats ainsi que des modules de calcul, opérationnels comme FONGEO pour les calculs bi et tridimensionnels ou FONDAX pour le

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

    Science.gov (United States)

    Bocher, L.; Delobelle, P.

    1997-09-01

    are very rich in informations and lead to classify the different types of loading, with two or three cyclic components, with respect to the observed supplementary hardening. This classification was established as follows: i) The in-phase tests with two or three components (δ = \\varphi = 0^circ); no supplementary hardening is observed. ii) The tension-pressure tests such as r_1 = 1, \\varphi = 90^circ and r_1 = - 1, \\varphi = 60^circ, the hardening is slightly inferior to that of tension-torsion tests. iii) The tension-torsion tests such as r_2 = 1 and δ = 90^circ, where a substantial additionnal hardening takes place. iv) The tension-torsion-pressure tests where the three components are strongly shifted, namely: r_1 = r_2 = 1, δ = 90^circ and \\varphi = 60^circ, and r_2 = 1, r_1 = -1, δ = 41.4^circ and \\varphi = 82.8^circ. The hardening is slightly superior to the one recorded in tension-torsion. A more thorough study is in preparation which considers all the possible combinations in tension-torsion-pressures, and will be performed on the same material. The early results tend to validate the observations presented in this article. Cette étude réside dans la détermination expérimentale du comportement à la température ambiante de l'acier inoxydable 316 L sous chargement cyclique non proportionnel en traction-torsion-pressions interne et externe. Les deux ou trois déformations sinusoïdales appliquées sont soit en phase, soit hors-phase et l'on étudie l'amplitude du durcissement supplémentaire en fonction du degré de multiaxialité. On présente quelques boucles stabilisées typiques. Par rapport au durcissement supplémentaire maximal, les différents essais peuvent être classés comme suit: essais en phase (pas de durcissement supplémentaire), essais de traction-pressions hors-phase, essais de traction-torsion hors phase et essais de traction-torsion-pressions avec déphasages conséquents.

  1. Étude du comportement du saumon atlantique (Salmo salar L. au niveau de l'aménagement hydroélectrique de Baigts (gave de Pau lors de sa migration anadrome.

    Directory of Open Access Journals (Sweden)

    CHANSEAU M.

    1999-04-01

    Full Text Available Le comportement de 19 saumons adultes (Salmo salar L. a été étudié au niveau de l'aménagement hydroélectrique de Baigts à l'aide de la technique de radiotélémétrie lors de trois expérimentations menées en été et en automne de 1995 à 1997. La majorité des poissons a stationné bien à l'aval de l'obstacle au cours de leur blocage. Les durées de présence en continu sur le site et les départs à l'aval étaient généralement inférieurs à 1 heure, les poissons se repliant au maximum à 200-300 m à l'aval de l'ouvrage avant de se présenter de nouveau sur le site. Lors de replis de durées plus importantes, généralement supérieures à 6 heures, les poissons stationnaient principalement dans un profond s'étendant de 500 m à 1,2 kilomètre de l'obstacle. Les départs du site se produisaient plutôt au crépuscule et les retours au pied de l'obstacle préférentiellement à l'aube, révélant une rythmicité comportementale des poissons au cours du nycthémère. Les températures moyennes journalières de l'eau et les débits turbines au niveau de l'usine ont eu une influence sur les présences des poissons au niveau de l'obstacle. Les saumons se présentaient plus souvent mais stationnaient moins longuement au pied de l'aménagement lorsque les températures étaient supérieures à 16°C. Les présences des poissons dans le canal de fuite étaient nettement réduites pour des températures supérieures à 20°C tandis que le stationnement au pied du barrage était plus important pour un fonctionnement réduit (débits turbines inférieurs à 50 m3/s de l'usine. Les études ont mis en évidence l'impact important de l'aménagement sur la migration anadrome des saumons, en regard notamment des durées de blocage importantes induites par l'aménagement (jusqu'à 137 jours et du faible nombre de poissons (34 % qui a réussi à passer à l'amont. L'emplacement de l'entrée du dispositif de franchissement, situé pourtant à l

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

    Science.gov (United States)

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

    2005-05-01

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

  3. Approach to syncope and altered mental status.

    Science.gov (United States)

    MacNeill, Emily C; Vashist, Sudhir

    2013-10-01

    Children who present with an episode of altered mental status, whether transient or persistent, present a diagnostic challenge for practitioners. This article describes some of the more common causes of altered mental status and delineates a rational approach to these patients. This will help practitioners recognize the life-threatening causes of these frightening presentations as well as help avoid unnecessary testing for the more benign causes. Copyright © 2013 Elsevier Inc. All rights reserved.

  4. Sleep Deprivation Alters Choice Strategy Without Altering Uncertainty or Loss Aversion Preferences

    Directory of Open Access Journals (Sweden)

    O'Dhaniel A Mullette-Gillman

    2015-10-01

    Full Text Available Sleep deprivation alters decision making; however, it is unclear what specific cognitive processes are modified to drive altered choices. In this manuscript, we examined how one night of total sleep deprivation (TSD alters economic decision making. We specifically examined changes in uncertainty preferences dissociably from changes in the strategy with which participants engage with presented choice information. With high test-retest reliability, we show that TSD does not alter uncertainty preferences or loss aversion. Rather, TSD alters the information the participants rely upon to make their choices. Utilizing a choice strategy metric which contrasts the influence of maximizing and satisficing information on choice behavior, we find that TSD alters the relative reliance on maximizing information and satisficing information, in the gains domain. This alteration is the result of participants both decreasing their reliance on cognitively-complex maximizing information and a concomitant increase in the use of readily-available satisficing information. TSD did not result in a decrease in overall information use in either domain. These results show that sleep deprivation alters decision making by altering the informational strategies that participants employ, without altering their preferences.

  5. Sleep deprivation alters choice strategy without altering uncertainty or loss aversion preferences.

    Science.gov (United States)

    Mullette-Gillman, O'Dhaniel A; Kurnianingsih, Yoanna A; Liu, Jean C J

    2015-01-01

    Sleep deprivation alters decision making; however, it is unclear what specific cognitive processes are modified to drive altered choices. In this manuscript, we examined how one night of total sleep deprivation (TSD) alters economic decision making. We specifically examined changes in uncertainty preferences dissociably from changes in the strategy with which participants engage with presented choice information. With high test-retest reliability, we show that TSD does not alter uncertainty preferences or loss aversion. Rather, TSD alters the information the participants rely upon to make their choices. Utilizing a choice strategy metric which contrasts the influence of maximizing and satisficing information on choice behavior, we find that TSD alters the relative reliance on maximizing information and satisficing information, in the gains domain. This alteration is the result of participants both decreasing their reliance on cognitively-complex maximizing information and a concomitant increase in the use of readily-available satisficing information. TSD did not result in a decrease in overall information use in either domain. These results show that sleep deprivation alters decision making by altering the informational strategies that participants employ, without altering their preferences.

  6. Cerebrospinal fluid space alterations in melancholic depression.

    Directory of Open Access Journals (Sweden)

    Esther Via

    Full Text Available Melancholic depression is a biologically homogeneous clinical entity in which structural brain alterations have been described. Interestingly, reports of structural alterations in melancholia include volume increases in Cerebro-Spinal Fluid (CSF spaces. However, there are no previous reports of CSF volume alterations using automated whole-brain voxel-wise approaches, as tissue classification algorithms have been traditionally regarded as less reliable for CSF segmentation. Here we aimed to assess CSF volumetric alterations in melancholic depression and their clinical correlates by means of a novel segmentation algorithm ('new segment', as implemented in the software Statistical Parametric Mapping-SPM8, incorporating specific features that may improve CSF segmentation. A three-dimensional Magnetic Resonance Image (MRI was obtained from seventy patients with melancholic depression and forty healthy control subjects. Although imaging data were pre-processed with the 'new segment' algorithm, in order to obtain a comparison with previous segmentation approaches, tissue segmentation was also performed with the 'unified segmentation' approach. Melancholic patients showed a CSF volume increase in the region of the left Sylvian fissure, and a CSF volume decrease in the subarachnoid spaces surrounding medial and lateral parietal cortices. Furthermore, CSF increases in the left Sylvian fissure were negatively correlated with the reduction percentage of depressive symptoms at discharge. None of these results were replicated with the 'unified segmentation' approach. By contrast, between-group differences in the left Sylvian fissure were replicated with a non-automated quantification of the CSF content of this region. Left Sylvian fissure alterations reported here are in agreement with previous findings from non-automated CSF assessments, and also with other reports of gray and white matter insular alterations in depressive samples using automated approaches

  7. Public health implications of altered puberty timing

    DEFF Research Database (Denmark)

    Golub, M.S.; Collman, G.W.; Foster, P.M.

    2008-01-01

    Changes in puberty timing have implications for the treatment of individual children, for the risk of later adult disease, and for chemical testing and risk assessment for the population. Children with early puberty are at a risk for accelerated skeletal maturation and short adult height, early...... sexual debut, potential sexual abuse, and psychosocial difficulties. Altered puberty timing is also of concern for the development of reproductive tract cancers later in life. For example, an early age of menarche is a risk factor for breast cancer. A low age at male puberty is associated....... Altered timing of puberty also has implications for behavioral disorders. For example, an early maturation is associated with a greater incidence of conduct and behavior disorders during adolescence. Finally, altered puberty timing is considered an adverse effect in reproductive toxicity risk assessment...

  8. Public health implications of altered puberty timing

    DEFF Research Database (Denmark)

    Golub, M.S.; Collman, G.W.; Foster, P.M.

    2008-01-01

    sexual debut, potential sexual abuse, and psychosocial difficulties. Altered puberty timing is also of concern for the development of reproductive tract cancers later in life. For example, an early age of menarche is a risk factor for breast cancer. A low age at male puberty is associated....... Altered timing of puberty also has implications for behavioral disorders. For example, an early maturation is associated with a greater incidence of conduct and behavior disorders during adolescence. Finally, altered puberty timing is considered an adverse effect in reproductive toxicity risk assessment......Changes in puberty timing have implications for the treatment of individual children, for the risk of later adult disease, and for chemical testing and risk assessment for the population. Children with early puberty are at a risk for accelerated skeletal maturation and short adult height, early...

  9. Mortar alteration: experimental study and ancient analogues

    International Nuclear Information System (INIS)

    Rassineux, Francois

    1987-01-01

    As the durability of cemented matrices is a matter of great importance in numerous domains, notably for the long term reliability of surface storages of radioactive wastes, the objective of this research thesis is to define mechanisms of evolution of cemented matrices when in contact with diluted aqueous solutions. The author notably studied the influence of the lixiviation mode on the evolution of two mortars having different compositions (pH, CO 2 pressure, system containment, and cement mineralogical nature appear to be the main governing parameters), the alteration (dissolution is the prevailing process in the interaction between cemented matrices and a diluted solution such as rain water), and ancient binders (archaeological binders containing mineral phases such as hydrated calcium silicates or hydro-grossulars). The obtained results lead to the definition of alteration mechanisms in modern cements, and highlight factors governing the durability of these materials when submitted to meteoric alteration [fr

  10. Alterations in physiology and anatomy during pregnancy.

    Science.gov (United States)

    Tan, Eng Kien; Tan, Eng Loy

    2013-12-01

    Pregnant women undergo profound anatomical and physiological changes so that they can cope with the increased physical and metabolic demands of their pregnancies. The cardiovascular, respiratory, haematological, renal, gastrointestinal and endocrine systems all undergo important physiological alterations and adaptations needed to allow development of the fetus and to allow the mother and fetus to survive the demands of childbirth. Such alterations in anatomy and physiology may cause difficulties in interpreting signs, symptoms, and biochemical investigations, making the clinical assessment of a pregnant woman inevitably confusing but challenging. Understanding these changes is important for every practicing obstetrician, as the pathological deviations from the normal physiological alterations may not be clear-cut until an adverse outcome has resulted. Only with a sound knowledge of the physiology and anatomy changes can the care of an obstetric parturient be safely optimized for a better maternal and fetal outcome. Copyright © 2013 Elsevier Ltd. All rights reserved.

  11. Streamflow alteration at selected sites in Kansas

    Science.gov (United States)

    Juracek, Kyle E.; Eng, Ken

    2017-06-26

    An understanding of streamflow alteration in response to various disturbances is necessary for the effective management of stream habitat for a variety of species in Kansas. Streamflow alteration can have negative ecological effects. Using a modeling approach, streamflow alteration was assessed for 129 selected U.S. Geological Survey streamgages in the State for which requisite streamflow and basin-characteristic information was available. The assessment involved a comparison of the observed condition from 1980 to 2015 with the predicted expected (least-disturbed) condition for 29 streamflow metrics. The metrics represent various characteristics of streamflow including average flow (annual, monthly) and low and high flow (frequency, duration, magnitude).Streamflow alteration in Kansas was indicated locally, regionally, and statewide. Given the absence of a pronounced trend in annual precipitation in Kansas, a precipitation-related explanation for streamflow alteration was not supported. Thus, the likely explanation for streamflow alteration was human activity. Locally, a flashier flow regime (typified by shorter lag times and more frequent and higher peak discharges) was indicated for three streamgages with urbanized basins that had higher percentages of impervious surfaces than other basins in the State. The combination of localized reservoir effects and regional groundwater pumping from the High Plains aquifer likely was responsible, in part, for diminished conditions indicated for multiple streamflow metrics in western and central Kansas. Statewide, the implementation of agricultural land-management practices to reduce runoff may have been responsible, in part, for a diminished duration and magnitude of high flows. In central and eastern Kansas, implemented agricultural land-management practices may have been partly responsible for an inflated magnitude of low flows at several sites.

  12. Experimental alterations on ceramic interest basalts

    International Nuclear Information System (INIS)

    Sanfeliu-Montolio, T.; Ballbe-Lonch, E.; Querlat-Mitjans, I.; Juan-Abril, A.; Fuente-Cellell, C. de la

    1991-01-01

    This study presents the results and conclusion extracted of the chemical and mineralogical analysis made on 12 samples of recent and subrecent (IV series) Canary Island's basalt, that have been subject to different attack processes in order to cause in them controlled mineralogical alterations. The methods used were: optical analysis, x-ray fluorescence analysis and x-ray diffraction. The object of this work is to determine the alterability of these basaltic rocks that have ceramic interest since it's possible its use in same ceramic manufactures and also as petrurgic raw material. (author)

  13. Questions Regarding Alterity in Social Collaborative Networks

    Directory of Open Access Journals (Sweden)

    Florinela Floria

    2010-01-01

    Full Text Available The idea of alterity has become important in the last decades, when talking about the Information Age, which provides acknowledgement to the software development specialists about the importance of understanding the other’s behavior, needs, objectives and beliefs.
    Our main purpose is to bring to attention the question of social representation related to the images of individuals as different entities that are integrated in virtual teams, virtual projects and e-activities. Regarding the consciousness about the other’s alterity, we assert that it opens a dialogical perspective about the Information Society, where it is essential to share and communicate knowledge to the others.

  14. Experimental study of kinetic and mechanism of dissolution of apatite structured minerals. Application to the prediction of the long term behavior of an actinides storage host matrix; Etude experimentale de la cinetique et des mecanismes d'alteration de mineraux apatitiques. Application au comportement d'une ceramique de confinement d'actinides mineurs

    Energy Technology Data Exchange (ETDEWEB)

    Chairat, C

    2005-11-15

    The motivation for this study is to assess the potential of using apatite structured ceramics as long-lived actinide storage hosts. To assess their ability to resist aqueous corrosion, the dissolution of natural fluoro-apatite and synthetic Nd-britholite (neodymium is a proxy for the trivalent actinides) was studied. Mineral surfaces were characterized using a combined spectrometric, electrokinetic and potentiometric approach and dissolution rates were measured in closed and open system reactors as a function of solution composition. Experimental results suggest apatitic minerals dissolve via distinct step sequence: 1) fluoride release, 2) release of the calcium situated in the M1, and 3) the simultaneous removal of phosphate and calcium II via the breaking of only Ca-O bonds. TST based rate equations based in this mechanism accurately describe fluoro-apatite and synthetic britholite dissolution rates as a function of solution composition. Nd release rates are limited by precipitation of Nd-rhabdophane. (author)

  15. Study of the behaviour of organic carbon in the soil, and carbon 14 study of podzols; Contribution a l'etude du comportement du carbone organique dans le sol et etude des podzols a l'aide du carbone 14

    Energy Technology Data Exchange (ETDEWEB)

    Nakhla Shawki, M. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1969-07-01

    Using the penetration into soil of carbon 14 of thermo-nuclear origin, the behaviour and renewal rate were studied on different organic fractions of the soil. It was established that 18% of the total organic matter is renewed in about 400 years. In addition the formation of podzol-type fossil soils in France was dated from the first millenary B.C., i.e. the end of the sub-boreal period and the beginning of the atlantic period. (author) [French] En utilisant la penetration dans le sol du carbone 14 d'origine thermonucleaire, on a etudie le comportement et la vitesse de renouvellement des differentes fractions de la matiere organique du sol. On a pu preciser que 18% de la matiere organique globale se renouvelait en 400 ans environ. Par ailleurs, la formation en France des sols fossiles du type podzol a ete datee du premier millenaire avant J.C. c'est a dire a la fin de la periode subboreale et au debut de la periode atlantique. (auteur)

  16. Caractérisation expérimentale du comportement mécanique d'assemblage haute température pour l'électronique de puissance Experimental characterization of the mechanical behavior of high-temperature assembly for power electronics

    Directory of Open Access Journals (Sweden)

    Baazaoui Ahlem

    2013-11-01

    Full Text Available Le comportement mécanique de deux types de connexion haute température mises en œuvre pour l'assemblage de composants d'électronique de puissance a été étudié : une jonction réalisée par brasage en phase liquide transitoire (TLPB d'Ag-In et une autre par brasage d'un eutectique Au88Ge12. Les connexions réalisées à partir d'inserts de cuivre sont caractérisées mécaniquement au moyen d'essais de cisaillement. Une analyse de la microstructure des jonctions en coupe et des faciès de rupture des deux connexions a également été menée. The mechanical behavior of two types of high-temperature connection implemented in the assembly of electronic power components was studied: a joint made by brazing transient liquid phase (TLPB Ag-In and in another by brazing Au88Ge12. Connections made are mechanically characterized using shear tests. The microstructure of the junction section and the fracture surfaces of both connections was also observed.

  17. I comportamenti violenti nel sonno REM: aspetti clinici, criminologici e medico-legali / Les comportements violents pendant le sommeil MOR : aspects cliniques, criminologiques et médico-légaux / The Violent Behaviour in REM Sleep-related: Clinical, Criminological and Forensic Aspects

    Directory of Open Access Journals (Sweden)

    Cimino Luca

    2011-04-01

    Full Text Available The violent behaviour of sleep represents a new frontier of forensic interest. After examining the clinical aspects of a particular form of parasomnia related to REM stage of sleep, called REM Behavior Disorder-RBD, the author highlights the criminological and forensic implications emphasizing the distinctive features in terms of responsibility and imputability.Les comportements violents pendant le sommeil MOR représentent une nouvelle “frontière” d’intérêt de la psychologie médico-légale. Après avoir examiné les aspects cliniques d’une forme particulière de parasomnie liée à la phase MOR du sommeil (denominata REM Behaviour Disorders-RBD, l’auteur de l’article met en évidence ses implications criminologiques et médico-légales; en outre, il souligne les aspects particuliers de cette parasomnie en matière de responsabilité et d’imputabilité.I comportamenti violenti del sonno rappresentano una nuova “frontiera” di interesse forense. L’autore, dopo aver esaminato gli aspetti clinici di una particolare forma di parasonnia legata alla fase REM del sonno, denominata REM Behaviour Disorders-RBD, ne sottolinea le implicazioni criminologiche e medico-legali sottolineandone gli aspetti peculiari in tema di colpa ed imputabilità.

  18. Sulphur depletion altered somatic embryogenesis in Theobroma ...

    African Journals Online (AJOL)

    Somatic embryogenesis is a useful tool for Theobroma cacao improvement and propagation. Depending on culture medium composition, different morphogenetic structures (including somatic embryo) occur in response to alteration of genes expression patterns and biochemical changes. The effect of SO42- ion deficiency ...

  19. Plutonium alteration phases from lanthanide borosilicate glass

    International Nuclear Information System (INIS)

    Fortner, J.A.; Mertz, C.J.; Chamberlain, D.C.; Bates, J.K.

    1997-01-01

    A prototype lanthanide borosilicate (LaBS) glass containing 10 mass % plutonium was reacted with water vapor at 200 C for periods of 14 to 56 days. These tests, while not designed to replicate specific conditions that may be found in a potential geologic repository (e.g., Yucca Mountain), have been shown to accelerate alteration phase formation. The surfaces of the glass samples, along with alteration phases, were examined with a transmission electron microscope (TEM). Tests of 14 days produced macroscopic (∼ 20 microm) crystallites of a plutonium-lanthanide silicate. An extensive alteration layer was found on the glass surface containing amorphous aluminosilicate layered with bands of a cryptocrystalline plutonium silicate. After 56 days of testing, additional alteration phases were formed, including a strontium lanthanide oxide phase. One of the options for disposal of surplus plutonium, particularly for impure residues that may be unfit for production of MOX fuel, is vitrification followed by geologic disposal. Since geologic disposal requires a passive system to isolate the radiotoxic elements from the biosphere, it is important to understand the possible corrosion mechanisms of the waste form

  20. rights reserved Geophysical Identification of Hydrothermally Altered ...

    African Journals Online (AJOL)

    ADOWIE PERE

    the pole to the magnetic data aided in mapping of various hydrothermally altered structures that may favour gold mineralisation. The interpretation of the aero data set has enhanced a lot of ... water serves as a concentrating, transporting and depositing agent through faults (structures) to the earth's surface. Hydrothermal ...

  1. Alterations in the human brain in menopause

    NARCIS (Netherlands)

    Ishunina, T.A.; Swaab, D.F.

    2007-01-01

    In a series of studies we showed that menopause in women causes alterations not only in the neuronal expression of estrogen receptors (ER) alpha and beta, but also in local estrogen production in several brain areas and in the rate of neuronal metabolism. Although such changes are clearly brain

  2. Can Molecular Hippocampal Alterations Explain Behavioral ...

    Science.gov (United States)

    Studies in both humans and animals have shown that prenatal stress can alter cognitive function and other neurological behaviors in adult offspring. One possible underlying mechanism for this may lie with alterations in hippocampal gene expression. The present study examined genotypical outcomes in adult male and female offspring of rats exposed to variable stress during pregnancy. Dams (n=15/treatment) were subjected to several non-chemical stressors including intermittent noise, light, crowding, restraint, and altered circadian lighting, from gestational day (GD) 13 to 20. Tail blood was drawn on GD 12, 16 and 20 to verify a stress response. Corticosterone levels were not different between the stressed and non-stressed dams on GD12 but was significantly increased in stressed dams on GD 16 and 20 compared to controls. Dams gave birth on GD22 (postnatal day or PND 0). Several behavioral tests were used to assess the cognitive and behavioral phenotype of the offspring from PND 49 through 86, including the Morris water maze and novel object recognition. Male and female stressed offspring showed reduced reversal learning on the Morris water maze and stressed females did not show a significant preference for the novel object (57 ± 8%) while control females did (71 ± 3%). This indicates altered cognition in prenatally stressed offspring. On PND 91-92, offspring were necropsied and hippocampal tissue was collected. Genotypic outcomes of prenatal stress w

  3. Altered States: Globalization, Sovereignty, and Governance | IDRC ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    In Altered States, Gordon Smith and Moisés Naím provide practical recommendations for improved governance and for strengthening and reforming the United Nations. They explore the dynamics of globalization and discuss what makes today's globalization distinct. They test the prevailing wisdom about sovereignty and ...

  4. Psychobiology of Altered States of Consciousness

    Science.gov (United States)

    Vaitl, Dieter; Birbaumer, Niels; Gruzelier, John; Jamieson, Graham A.; Kotchoubey, Boris; Kubler, Andrea; Lehmann, Dietrich; Miltner, Wolfgang H. R.; Ott, Ulrich; Sammer, Gebhard; Strauch, Inge; Strehl, Ute; Wackermann, Jiri; Weiss, Thomas

    2005-01-01

    The article reviews the current knowledge regarding altered states of consciousness (ASC) (a) occurring spontaneously, (b) evoked by physical and physiological stimulation, (c) induced by psychological means, and (d) caused by diseases. The emphasis is laid on psychological and neurobiological approaches. The phenomenological analysis of the…

  5. Genistein Precipitated Hypothyroidism, Altered Leptin and C ...

    African Journals Online (AJOL)

    Genistein Precipitated Hypothyroidism, Altered Leptin and C-Reactive Protein Synthesis in Pregnant Rats. ... Thyroid hormone, C-reactive protein (CRP) and leptin assay was carried using the blood samples. Leptin was also assayed in the placenta and amniotic fluid supernatant. Oral exposure of pregnant rats to genistein ...

  6. Chronic Allium sativum administration alters spontaneous ...

    African Journals Online (AJOL)

    This study was conducted to investigate the effects of Allium sativum extract on the medial prefrontal cortex and neurobehaviour of adult Wistar rats. ... altered spontaneous alternation, while cellular pathologic changes were observed in the medial prefrontal cortex of these test groups in a dose dependent sequence.

  7. Altered membrane permeability in multidrug resistant Escherichia ...

    African Journals Online (AJOL)

    The study was conducted with the objective of examining the outer membrane proteins and their involvement during the transport of β - lactams in multidrug resistant Escherichia coli isolated from extra-intestinal infections. Also, the response of gram negative bacterial biomembrane alteration was studied using extended ...

  8. Connective tissue alteration in abdominal wall hernia

    DEFF Research Database (Denmark)

    Henriksen, N A; Yadete, D H; Sørensen, Lars Tue

    2011-01-01

    The aetiology and pathogenesis of abdominal wall hernia formation is complex. Optimal treatment of hernias depends on a full understanding of the pathophysiological mechanisms involved in their formation. The aim of this study was to review the literature on specific collagen alterations...... in abdominal wall hernia formation....

  9. Restraint Stress Impairs Glucose Homeostasis Through Altered ...

    African Journals Online (AJOL)

    olayemitoyin

    Summary: The study investigated the potential alteration in the level of insulin and adiponectin, as well as the expression of insulin receptors (INSR) and glucose transporter 4 GLUT-4 in chronic restraint stress rats. Sprague-Dawley rats were randomly divided into two groups: the control group and stress group in which the ...

  10. Geophysical Identification of Hydrothermally Altered Structures That ...

    African Journals Online (AJOL)

    This research study uses geophysical method (aeromagnetic) to identify hydrothermally altered structures which favour the inflow of hydrothermal fluid that usually brings about gold mineralisation in Egbe-Isanlu Schist Belt Area, North Central Nigeria. The application of data enhancement filtering algorithm such as ...

  11. Global alteration of climate - hopes and fears

    International Nuclear Information System (INIS)

    Viktorov, V.V.

    1992-01-01

    Problems concerning gaseous emission affecting the global climate alteration connected with hotbed effect are considered. Economical and social-political ways of solution of the problem of minimization of gaseous wastes are described. Role of nuclear power plants and alternative power plants in the hotbed effect are analyzed. International cooperation in environmental protection policy is discussed

  12. Rare endocrine cancers have novel genetic alterations

    Science.gov (United States)

    A molecular characterization of adrenocortical carcinoma, a rare cancer of the adrenal cortex, analyzed 91 cases for alterations in the tumor genomes and identified several novel genetic mutations as likely mechanisms driving the disease as well as whole genome doubling as a probable driver of the disease.

  13. Altered gut microbiota in Rett syndrome.

    Science.gov (United States)

    Strati, Francesco; Cavalieri, Duccio; Albanese, Davide; De Felice, Claudio; Donati, Claudio; Hayek, Joussef; Jousson, Olivier; Leoncini, Silvia; Pindo, Massimo; Renzi, Daniela; Rizzetto, Lisa; Stefanini, Irene; Calabrò, Antonio; De Filippo, Carlotta

    2016-07-30

    The human gut microbiota directly affects human health, and its alteration can lead to gastrointestinal abnormalities and inflammation. Rett syndrome (RTT), a progressive neurological disorder mainly caused by mutations in MeCP2 gene, is commonly associated with gastrointestinal dysfunctions and constipation, suggesting a link between RTT's gastrointestinal abnormalities and the gut microbiota. The aim of this study was to evaluate the bacterial and fungal gut microbiota in a cohort of RTT subjects integrating clinical, metabolomics and metagenomics data to understand if changes in the gut microbiota of RTT subjects could be associated with gastrointestinal abnormalities and inflammatory status. Our findings revealed the occurrence of an intestinal sub-inflammatory status in RTT subjects as measured by the elevated values of faecal calprotectin and erythrocyte sedimentation rate. We showed that, overall, RTT subjects harbour bacterial and fungal microbiota altered in terms of relative abundances from those of healthy controls, with a reduced microbial richness and dominated by microbial taxa belonging to Bifidobacterium, several Clostridia (among which Anaerostipes, Clostridium XIVa, Clostridium XIVb) as well as Erysipelotrichaceae, Actinomyces, Lactobacillus, Enterococcus, Eggerthella, Escherichia/Shigella and the fungal genus Candida. We further observed that alterations of the gut microbiota do not depend on the constipation status of RTT subjects and that this dysbiotic microbiota produced altered short chain fatty acids profiles. We demonstrated for the first time that RTT is associated with a dysbiosis of both the bacterial and fungal component of the gut microbiota, suggesting that impairments of MeCP2 functioning favour the establishment of a microbial community adapted to the costive gastrointestinal niche of RTT subjects. The altered production of short chain fatty acids associated with this microbiota might reinforce the constipation status of RTT

  14. 28 CFR 36.403 - Alterations: Path of travel.

    Science.gov (United States)

    2010-07-01

    ... 28 Judicial Administration 1 2010-07-01 2010-07-01 false Alterations: Path of travel. 36.403... Alterations: Path of travel. (a) General. An alteration that affects or could affect the usability of or... the maximum extent feasible, the path of travel to the altered area and the restrooms, telephones, and...

  15. Epigenetic alteration of sedimentary rocks at hydrogenic uranium deposit

    International Nuclear Information System (INIS)

    Ding Wanlie; Shen Kefeng

    2001-01-01

    The author introduces the concept, the recognition criteria, the genesis and classification of the epigenetic alteration of sedimentary rocks in brief, and expounds the mineral-geochemical indications and characteristics of oxidation and reduction alterations in different geochemical zones in detail, and proposes the two models of ore-controlling zonation of epigenetic alteration. The authors finally introduce research methods of epigenetic alteration

  16. Alteration of consciousness in focal epilepsy: the global workspace alteration theory.

    Science.gov (United States)

    Bartolomei, Fabrice; McGonigal, Aileen; Naccache, Lionel

    2014-01-01

    Alteration of consciousness (AOC) is an important clinical manifestation of partial seizures that greatly impacts the quality of life of patients with epilepsy. Several theories have been proposed in the last fifty years. An emerging concept in neurology is the global workspace (GW) theory that postulates that access to consciousness (from several sensorial modalities) requires transient coordinated activity from associative cortices, in particular the prefrontal cortex and the posterior parietal associative cortex. Several lines of evidence support the view that partial seizures alter consciousness through disturbance of the GW. In particular, a nonlinear relation has been shown between excess of synchronization in the GW regions and the degree of AOC. Changes in thalamocortical synchrony occurring during the spreading of the ictal activity seem particularly involved in the mechanism of altered consciousness. This link between abnormal synchrony and AOC offers new perspectives in the treatment of the AOC since means of decreasing consciousness alteration in seizures could improve patients' quality of life. © 2013.

  17. Metabolic alterations in renal cell carcinoma.

    Science.gov (United States)

    Massari, Francesco; Ciccarese, Chiara; Santoni, Matteo; Brunelli, Matteo; Piva, Francesco; Modena, Alessandra; Bimbatti, Davide; Fantinel, Emanuela; Santini, Daniele; Cheng, Liang; Cascinu, Stefano; Montironi, Rodolfo; Tortora, Giampaolo

    2015-11-01

    Renal cell carcinoma (RCC) is a metabolic disease, being characterized by the dysregulation of metabolic pathways involved in oxygen sensing (VHL/HIF pathway alterations and the subsequent up-regulation of HIF-responsive genes such as VEGF, PDGF, EGF, and glucose transporters GLUT1 and GLUT4, which justify the RCC reliance on aerobic glycolysis), energy sensing (fumarate hydratase-deficient, succinate dehydrogenase-deficient RCC, mutations of HGF/MET pathway resulting in the metabolic Warburg shift marked by RCC increased dependence on aerobic glycolysis and the pentose phosphate shunt, augmented lipogenesis, and reduced AMPK and Krebs cycle activity) and/or nutrient sensing cascade (deregulation of AMPK-TSC1/2-mTOR and PI3K-Akt-mTOR pathways). We analyzed the key metabolic abnormalities underlying RCC carcinogenesis, highlighting those altered pathways that may represent potential targets for the development of more effective therapeutic strategies. Copyright © 2015 Elsevier Ltd. All rights reserved.

  18. Molecular alterations and biomarkers in colorectal cancer

    Science.gov (United States)

    Grady, William M.; Pritchard, Colin C.

    2013-01-01

    The promise of precision medicine is now a clinical reality. Advances in our understanding of the molecular genetics of colorectal cancer genetics is leading to the development of a variety of biomarkers that are being used as early detection markers, prognostic markers, and markers for predicting treatment responses. This is no more evident than in the recent advances in testing colorectal cancers for specific molecular alterations in order to guide treatment with the monoclonal antibody therapies cetuximab and panitumumab, which target the epidermal growth factor receptor (EGFR). In this review, we update a prior review published in 2010 and describe our current understanding of the molecular pathogenesis of colorectal cancer and how these alterations relate to emerging biomarkers for early detection and risk stratification (diagnostic markers), prognosis (prognostic markers), and the prediction of treatment responses (predictive markers). PMID:24178577

  19. Epigenetic alterations of sedimentary rocks at deposits

    International Nuclear Information System (INIS)

    Komarova, G.V.; Kondrat'eva, I.A.; Zelenova, O.I.

    1980-01-01

    Notions are explained, and technique for studying epigenetic alterations of sedimentary rocks at uranium deposits is described. Main types of epigenetic transformations and their mineralogic-geochemical characteristics are considered. Rock alterations, accompanying uranium mineralization, can be related to 2 types: oxidation and reduction. The main mineralogic-geochemical property of oxidation transformations is epigenetic limonitization. Stratal limonitization in primary grey-coloured terrigenic rocks and in epigenetically reduced (pyritized) rocks, as well as in rock, subjected to epigenetic gleying, are characterized. Reduction type of epigenetic transformations is subdivided into sulphidic and non-sulphidic (gley) subtypes. Sulphidic transformations in grey-coloured terrigenic rocks with organic substance of carbonic row, in rocks, containing organic substance of oil row, sulphide transformations of sedimentary rocks, as well as gley transformations, are considered

  20. Siliceous microfossil extraction from altered Monterey rocks

    Energy Technology Data Exchange (ETDEWEB)

    Nelson, C.O.; Casey, R.E.

    1986-04-01

    Samples of altered Monterey rocks of differing lithologies were processed by various methods to develop new techniques for extracting siliceous microfossils. The preliminary use of thin sections made from the same rocks reduced the number of probable samples (samples worth further processing) by about one-third. Most of the siliceous microfossils contained in altered Monterey rocks appear to be highly recrystallized and are extremely fragile; however, some contained silicified and silica-infilled radiolarians and planktonic and benthonic foraminifera, which are very tough. In general the most useful techniques were gently hydrochloric acid, hydrogen peroxide, formic acid, monosodium glutamate, and regular siliceous microfossil extraction techniques. Unsuccessful techniques and a new siliceous microfossil flotation technique are also documented.

  1. Altered Sensory Feedbacks in Pianist's Dystonia: the altered auditory feedback paradigm and the glove effect

    Directory of Open Access Journals (Sweden)

    Felicia Pei-Hsin Cheng

    2013-12-01

    Full Text Available Background: This study investigates the effect of altered auditory feedback (AAF in musician's dystonia (MD and discusses whether altered auditory feedback can be considered as a sensory trick in MD. Furthermore, the effect of AAF is compared with altered tactile feedback, which can serve as a sensory trick in several other forms of focal dystonia. Methods: The method is based on scale analysis (Jabusch et al. 2004. Experiment 1 employs synchronization paradigm: 12 MD patients and 25 healthy pianists had to repeatedly play C-major scales in synchrony with a metronome on a MIDI-piano with 3 auditory feedback conditions: 1. normal feedback; 2. no feedback; 3. constant delayed feedback. Experiment 2 employs synchronization-continuation paradigm: 12 MD patients and 12 healthy pianists had to repeatedly play C-major scales in two phases: first in synchrony with a metronome, secondly continue the established tempo without the metronome. There are 4 experimental conditions, among them 3 are the same altered auditory feedback as in Experiment 1 and 1 is related to altered tactile sensory input. The coefficient of variation of inter-onset intervals of the key depressions was calculated to evaluate fine motor control. Results: In both experiments, the healthy controls and the patients behaved very similarly. There is no difference in the regularity of playing between the two groups under any condition, and neither did AAF nor did altered tactile feedback have a beneficial effect on patients’ fine motor control. Conclusions: The results of the two experiments suggest that in the context of our experimental designs, AAF and altered tactile feedback play a minor role in motor coordination in patients with musicians' dystonia. We propose that altered auditory and tactile feedback do not serve as effective sensory tricks and may not temporarily reduce the symptoms of patients suffering from MD in this experimental context.

  2. Ocean acidification alters fish–jellyfish symbiosis

    Science.gov (United States)

    Nagelkerken, Ivan; Pitt, Kylie A.; Rutte, Melchior D.; Geertsma, Robbert C.

    2016-01-01

    Symbiotic relationships are common in nature, and are important for individual fitness and sustaining species populations. Global change is rapidly altering environmental conditions, but, with the exception of coral–microalgae interactions, we know little of how this will affect symbiotic relationships. We here test how the effects of ocean acidification, from rising anthropogenic CO2 emissions, may alter symbiotic interactions between juvenile fish and their jellyfish hosts. Fishes treated with elevated seawater CO2 concentrations, as forecast for the end of the century on a business-as-usual greenhouse gas emission scenario, were negatively affected in their behaviour. The total time that fish (yellowtail scad) spent close to their jellyfish host in a choice arena where they could see and smell their host was approximately three times shorter under future compared with ambient CO2 conditions. Likewise, the mean number of attempts to associate with jellyfish was almost three times lower in CO2-treated compared with control fish, while only 63% (high CO2) versus 86% (control) of all individuals tested initiated an association at all. By contrast, none of three fish species tested were attracted solely to jellyfish olfactory cues under present-day CO2 conditions, suggesting that the altered fish–jellyfish association is not driven by negative effects of ocean acidification on olfaction. Because shelter is not widely available in the open water column and larvae of many (and often commercially important) pelagic species associate with jellyfish for protection against predators, modification of the fish–jellyfish symbiosis might lead to higher mortality and alter species population dynamics, and potentially have flow-on effects for their fisheries. PMID:27358374

  3. Silychristin: Skeletal Alterations and Biological Activities

    Czech Academy of Sciences Publication Activity Database

    Biedermann, David; Buchta, M.; Holečková, Veronika; Sedlák, David; Valentová, Kateřina; Cvačka, Josef; Bednárová, Lucie; Křenková, Alena; Kuzma, Marek; Škuta, Ctibor; Peikerová, Žaneta; Bartůněk, Petr; Křen, Vladimír

    2016-01-01

    Roč. 79, č. 12 (2016), s. 3086-3092 ISSN 0163-3864 R&D Projects: GA ČR(CZ) GA15-03037S; GA MZd(CZ) NV16-27317A; GA MŠk LO1220; GA MŠk LM2015063; GA MŠk(CZ) LD15081 Institutional support: RVO:61388971 ; RVO:68378050 ; RVO:61388963 Keywords : Silychristin * skeletal alterations * biological activities Subject RIV: CC - Organic Chemistry Impact factor: 3.281, year: 2016

  4. [Colorectal cancer (CCR): genetic and molecular alterations].

    Science.gov (United States)

    Juárez-Vázquez, Clara Ibet; Rosales-Reynoso, Mónica Alejandra

    2014-01-01

    The aim of this review is to present a genetic and molecular overview of colorectal carcinogenesis (sporadic and hereditary origin) as a multistage process, where there are a number of molecular mechanisms associated with the development of colorectal cancer and genomic instability that allows the accumulation of mutations in proto-oncogenes and tumor suppressor genes, chromosomal instability, and methylation and microsatellite instability, and the involvement of altered expression of microRNAs' prognosis factors.

  5. Oncometabolites: linking altered metabolism with cancer

    Science.gov (United States)

    Yang, Ming; Soga, Tomoyoshi; Pollard, Patrick J.

    2013-01-01

    The discovery of cancer-associated mutations in genes encoding key metabolic enzymes has provided a direct link between altered metabolism and cancer. Advances in mass spectrometry and nuclear magnetic resonance technologies have facilitated high-resolution metabolite profiling of cells and tumors and identified the accumulation of metabolites associated with specific gene defects. Here we review the potential roles of such “oncometabolites” in tumor evolution and as clinical biomarkers for the detection of cancers characterized by metabolic dysregulation. PMID:23999438

  6. Alterations of brain activity in fibromyalgia patients.

    Science.gov (United States)

    Sawaddiruk, Passakorn; Paiboonworachat, Sahattaya; Chattipakorn, Nipon; Chattipakorn, Siriporn C

    2017-04-01

    Fibromyalgia is a chronic pain syndrome, characterized by widespread musculoskeletal pain with diffuse tenderness at multiple tender points. Despite intense investigations, the pathophysiology of fibromyalgia remains elusive. Evidence shows that it could be due to changes in either the peripheral or central nervous system (CNS). For the CNS changes, alterations in the high brain area of fibromyalgia patients have been investigated but the definite mechanisms are still unclear. Magnetic Resonance Imaging (MRI) and Functional Magnetic Resonance (fMRI) have been used to gather evidence regarding the changes of brain morphologies and activities in fibromyalgia patients. Nevertheless, due to few studies, limited knowledge for alterations in brain activities in fibromyalgia is currently available. In this review, the changes in brain activity in various brain areas obtained from reports in fibromyalgia patients are comprehensively summarized. Changes of the grey matter in multiple regions such as the superior temporal gyrus, posterior thalamus, amygdala, basal ganglia, cerebellum, cingulate cortex, SII, caudate and putamen from the MRI as well as the increase of brain activities in the cerebellum, prefrontal cortex, anterior cingulate cortex, thalamus, somatosensory cortex, insula in fMRI studies are presented and discussed. Moreover, evidence from pharmacological interventions offering benefits for fibromyalgia patients by reducing brain activity is presented. Because of limited knowledge regarding the roles of brain activity alterations in fibromyalgia, this summarized review will encourage more future studies to elucidate the underlying mechanisms involved in the brains of these patients. Copyright © 2017 Elsevier Ltd. All rights reserved.

  7. Extracellular matrix alterations in the Peyronie's disease.

    Science.gov (United States)

    Watanabe, Marcelo Silva; Theodoro, Thérèse Rachel; Coelho, Natália Lima; Mendes, Aline; Leonel, Monica Luzia Pereira; Mader, Ana Maria; Nader, Helena Bonciani; Glina, Sidney; Pinhal, Maria Aparecida Silva

    2017-07-01

    Peyronie's disease is characterized by fibrous plaque formation of the tunica albuginea, causing penile deformity and fertility problems. The aim of the present study was to investigate alterations in the extracellular matrix in Peyronie's disease. The study used tissues collected by surgical procedure from individuals that presented a well-established disease, while control samples were obtained by biopsies of fresh cadavers. Immunohistochemistry analysis followed by digital quantification was performed to evaluate TGF-β, heparanases and metalloproteinases (MMPs). The profile of sulfated glycosaminoglycans, chondroitin sulfate and dermatan sulfate was determined by agarose gel electrophoresis, while hyaluronic acid quantification was obtained by an ELISA-like assay. The expression of mRNA was investigated for syndecan-1 proteoglycan (Syn-1), interleukine-6 (IL-6), hyaluronic acid synthases, and hyaluronidases. Pathologic features showed decreased apoptosis and blood vessel number in Peyronie's tissues. TGF-β and IL-6 were significantly enhanced in Peyronie's disease. There was an increased expression of heparanases, though no alteration was observed for MMPs. Hyaluronic acid as well as hyaluronic acid synthases, hyaluronidases, and dermatan sulfate were not changed, while the level of chondroitin sulfate was significantly ( P  = 0.008, Mann-Whitney test) increased in Peyronie's samples. Heparanases and sulfated glycosaminoglycans seem to be involved in extracellular matrix alterations in Peyronie's disease.

  8. Chromite alteration processes within Vourinos ophiolite

    Science.gov (United States)

    Grieco, Giovanni; Merlini, Anna

    2012-09-01

    The renewed interest in chromite ore deposits is directly related to the increase in Cr price ruled by international market trends. Chromite, an accessory mineral in peridotites, is considered to be a petrogenetic indicator because its composition reflects the degree of partial melting that the mantle experienced while producing the chromium spinel-bearing rock (Burkhard in Geochim Cosmochim Acta 57:1297-1306, 1993). However, the understanding of chromite alteration and metamorphic modification is still controversial (e.g. Evans and Frost in Geochim Cosmochim Acta 39:959-972, 1975; Burkhard in Geochim Cosmochim Acta 57:1297-1306, 1993; Oze et al. in Am J Sci 304:67-101, 2004). Metamorphic alteration leads to major changes in chromite chemistry and to the growth of secondary phases such as ferritchromite and chlorite. In this study, we investigate the Vourinos complex chromitites (from the mines of Rizo, Aetoraches, Xerolivado and Potamia) with respect to textural and chemical analyses in order to highlight the most important trend of alteration related to chromite transformation. The present study has been partially funded by the Aliakmon project in collaboration between the Public Power Corporation of Greece and Institute of Geology and Mineral Exploration of Kozani.

  9. Obesogenic diets alter metabolism in mice.

    Science.gov (United States)

    Showalter, Megan R; Nonnecke, Eric B; Linderholm, A L; Cajka, Tomas; Sa, Michael R; Lönnerdal, Bo; Kenyon, Nicholas J; Fiehn, Oliver

    2018-01-01

    Obesity and accompanying metabolic disease is negatively correlated with lung health yet the exact mechanisms by which obesity affects the lung are not well characterized. Since obesity is associated with lung diseases as chronic bronchitis and asthma, we designed a series of experiments to measure changes in lung metabolism in mice fed obesogenic diets. Mice were fed either control or high fat/sugar diet (45%kcal fat/17%kcal sucrose), or very high fat diet (60%kcal fat/7% sucrose) for 150 days. We performed untargeted metabolomics by GC-TOFMS and HILIC-QTOFMS and lipidomics by RPLC-QTOFMS to reveal global changes in lung metabolism resulting from obesity and diet composition. From a total of 447 detected metabolites, we found 91 metabolite and lipid species significantly altered in mouse lung tissues upon dietary treatments. Significantly altered metabolites included complex lipids, free fatty acids, energy metabolites, amino acids and adenosine and NAD pathway members. While some metabolites were altered in both obese groups compared to control, others were different between obesogenic diet groups. Furthermore, a comparison of changes between lung, kidney and liver tissues indicated few metabolic changes were shared across organs, suggesting the lung is an independent metabolic organ. These results indicate obesity and diet composition have direct mechanistic effects on composition of the lung metabolome, which may contribute to disease progression by lung-specific pathways.

  10. Chemistry, mineralogy and alteration intensity of hydrothermal altered Mt Unzen conduit rocks (Shimabara/Japan)

    Science.gov (United States)

    Hess, Kai-Uwe; Yilmaz, Tim; Gilg, H. Albert; Janots, Emilie; Mayer, Klaus; Nakada, Setsuya; Dingwell, Donald

    2017-04-01

    Investigations were carried out on hydrothermally altered coherent dacitic dykes samples from (USDP-4) drill core at Mt Unzen stratovolcano (Shimabara/Japan). XRF, XRD, EMPA, C-O-isotope, hot-cathode CL and SEM analysis led to insights concerning chemistry, mineralogy, and intensity and type of alteration as well as the origin of carbonate-precipitating fluids. Additionally a textural characterization of the occurring replacement features in the volcanic conduit rocks was performed. The occurrence of the main secondary phases such as chlorite, pyrite, carbonates, and R1 (Reichweite parameter) illite-smectite and kaolinite group minerals indicate a weak to moderate propylitic to phyllic hydrothermal alteration. The dacitic samples of the dykes show different hydrothermal alteration features: (i) carbonate and chlorite pseudomorphs after hornblende as well as core and zonal textures due to replacement of plagioclase by R1 illite-smectite as well as kaolinite group minerals, (ii) colloform banded fracture fillings and fillings in dissolution vugs, and (iii) chlorite, R1 illite-smectite as well as kaolinite group minerals in the groundmass. Late chlorite veins crosscut precipitates of R1 illite-smectite as well as kaolinite group minerals. Carbonates in fractures and in pseudomorphs after hornblende comprise iron-rich dolomite solid solutions ("ankerite") and calcite. Isotopic values indicate a hydrothermal-magmatic origin for the carbonate formation. The chlorite-carbonate-pyrite index (CCPI) and the Ishikawa alteration index (AI), applied to the investigated samples show significant differences (CCPI=52.7-57.8; AI=36.1-40.6) indicating their different degree of alteration. According to Nakada et al., 2005, the C13 to C16 dykes represent the feeder dyke from the latest eruption (1991-1995) whereas C8 represents an earlier dyke feeder dyke from an older eruption. Weakest alteration, which was obtained in samples C16-1-5 and C13-2-5, correlates with the alteration

  11. The geology of uranium in the Saint-Sylvestre granite district (Limousin, Massif Central, France); La geologie de l'uranium dans le massif granitique de Saint-Sylvestre (Limousin - Massif Central Francais)

    Energy Technology Data Exchange (ETDEWEB)

    Marquaire, C.; Moreau, M.; Barbier, J.; Ranchin, G.; Carrat, H.G.; Coppens, R.; Senecal, J.; Koszotolanyi, C.; Dottin, H

    1969-07-01

    This report concerns the geology of uranium in Limousin, more particularly in the St-Sylvestre massif, and the related phenomena: regional geology, petrographic and geochemical zonal distribution observed in various granite massifs, uranium movement in connection with surface alteration, geochronology of uranium ore. The work is made up of six articles covering the various scientific aspects listed above. Each article is headed with an abstract. The paper comprises the following chapters: Foreword by Marcel ROUBAULT. 1. Ch. MARQUAIRE, M. MOREAU Outline of geological conditions in Northern Limousin and distribution of uraniferous occurrences. 2. J. BARBIER, G. RANCHIN, H. G. CARRAT and R. COPPENS Geology of the St-Sylvestre Massif and uranium geochemistry - Introduction to laboratory studies - Problems of methodology. 3. J. BARBIER and G. RANCHIN Petrographical and geochemical zones in the St-Sylvestre granite massif (Limousin - French 'Massif Central'). 4. J. BARBIER and G. RANCHIN Uranium geochemistry in the St-Sylvestre Massif (Limousin - French 'Massif Central') - Occurrences of primary geochemical uranium and replacement processes. 5. J. SENEGAL Monograph of the Brugeaud orebody. 6. R. COPPENS, Ch. KOSZTOLANYI and H. DOTTIN Geochronological study of the Brugeaud mine. 1969. (authors) [French] Ce memoire est consacre a la geologie de l'uranium dans le Limousin, plus specialement dans le massif de St-Sylvestre, et aux phenomenes qui s'y rattachent: geologie regionale, phenomenes de zonalite petrographique et geochimique dans certains massifs granitiques, mouvements de l'uranium lies a l'alteration superficielle, geochronologie du minerai d'uranium. L'ouvrage comprend six articles qui recouvrent les differents aspects scientifiques enumeres. Chacun de ces six articles est precede d'un resume. La composition du memoire st la suivante: Marcel ROUBAULT, Preface. 1. Ch. MARQUAIRE, M. MOREAU Esquisse geologique du

  12. Effect of Added Surfactants on the Dynamic Interfacial Tension Behaviour of Alkaline/Diluted Heavy Crude Oil System Effet de l’ajout de tensioactifs sur le comportement dynamique de la tension interfaciale du système solution alcaline/brut dilué

    Directory of Open Access Journals (Sweden)

    Trabelsi S.

    2013-02-01

    Full Text Available This study has been undertaken to get a better understanding of the interactions between Enhanced Oil Recovery (EOR surfactants used in chemical flooding and in situ surfactants present in an heavy oil. We report an experimental study of dynamic Interfacial Tension (IFT behaviour of diluted heavy oil/surfactant enhanced-alkaline systems. The dynamic IFT was measured using pendant drop and spinning drop tensiometers. The dynamic IFT between diluted heavy oil and alkaline solution (pH 11 with no added surfactant increased sharply with time, which was attributed to the transfer of the in situ surfactant (produced by saponification of the acids groups present in the crude oil across the oil/water interface. The addition of Sodium Dodecyl Benzene Sulfonate (SDBS above the Critical Micellar Concentration (CMC ~ 0.002%, changed completely the dynamic IFT behaviour of the diluted heavy oil as the IFT strongly decreased and finally reached a plateau, of about 1.5 × 10-3 mN/m at a concentration of only 0.02%. We attributed the efficiency of SDBS to a synergistic effect between the in situ surfactant and the added surfactant that form a mixed interfacial monolayer, which is very efficient in decreasing the IFT to ultra low values and in resisting mass transfer across the oil/water interface. Cette étude a été réalisée pour mieux comprendre les interactions entre les tensioactifs utilisés pour la récupération assistée de pétrole et les tensioactifs in situ présents dans le brut. Nous expérimentons le comportement dynamique des tensions interfaciales (mesurées par les méthodes de goutte pendante et goutte tournante entre le brut lourd dilué et les solutions alcalines avec ajout de tensioactif. La tension interfaciale dynamique entre le brut dilué et une solution alcaline (pH 11 sans ajout de tensioactif croît fortement au cours du temps, cette augmentation est attribuée au transfert des tensioactifs in situ (produits par saponification des

  13. Efficacité d'un exutoire de dévalaison pour smolts de saumon atlantique (Salmo salar L. et comportement des poissons au niveau de l'aménagement hydroélectrique de Camon sur la Garonne

    Directory of Open Access Journals (Sweden)

    CROZE O.

    1999-04-01

    Full Text Available Trois expérimentations ont été conduites de 1996 à 1998 au niveau de la prise d'eau de l'usine hydroélectrique de Camon, sur la Garonne, de manière à tester l'efficacité d'un exutoire de surface destiné aux smolts de saumon atlantique. Ce dispositif de dévalaison est situé en rive gauche, au niveau du plan des grilles. Son efficacité a été évaluée par la méthode de marquage-recapture et le comportement des smolts dans le canal d'amenée a été suivi grâce à la technique de radio-pistage. L'efficacité initiale du dispositif est apparue faible en 1996 (moyenne de 34 % . Le suivi par radio-pistage a révélé que l'emplacement de l'exutoire n'était pas responsable de sa faible efficacité, les poissons stationnant préférentiellement à proximité. Cependant, la présence d'une ascendance masque son entrée. Suite à la mise en place d'une grille de tranquillisation et de platelages horizontaux au niveau de l'entrée de l'exutoire, cette efficacité a été portée à une valeur moyenne de 73 %. De bonnes conditions hydrauliques générales dans le canal d'amenée associées à une hydrodynamique locale favorable aux environs immédiats de l'entrée de l'exutoire s'avèrent indispensables à l'obtention d'une efficacité satisfaisante du dispositif de dévalaison. L'utilisation d'un éclairage nocturne intermittent a non seulement eu un effet sur le comportement des smolts dans le canal d'amenée en maintenant ces derniers dans les zones directement éclairées mais aussi sur les rythmes d'entrée des poissons dans l'exutoire, les passages apparaissant principalement en début d'extinction. La capture de 7 715 salmonidés sauvages a permis d'étudier les rythmes de dévalaison au niveau d'un obstacle. Les pics journaliers de passage semblent liés principalement à de forts débits et/ou à une augmentation de la température de l'eau. L'activité de dévalaison au niveau d'un obstacle apparaît en outre essentiellement

  14. Identification et étude du comportement de quelques additifs des huiles moteurs à base minérale par spectrophotométries IR intégrale et différentielle Identification and Study of the Behavior of Several Additives for Mineral-Bass Motor Oils by Differential and Integral Ir Spectrophotometry

    Directory of Open Access Journals (Sweden)

    Subran C.

    2006-11-01

    Full Text Available L'utilisation d'additifs dans les huiles moteurs est un facteur déterminant pour la longévité et les performances des moteurs. On présente dans cet article quelques procédés d'identification de certains additifs (améliorant d'indice de viscosité, antioxydants, détergents, antimousse, abaisseur du point de congélation en utilisant les méthodes de la spectroscopie IR différentielle et intégrale, l'étude de leur comportement durant l'altération des huiles, le contrôle des dosages dans les huiles neuves. La technique est caractérisée par sa rapidité, par les faibles quantités d'huile prélevées (millilitres, par la possibilité d'un contrôle permanent et d'un diagnostique possible de l'ensemble huile-moteur. The addition of additives to motor oils is one of the main factors in determining the optimum duration of the use of an oil as well as the lifetime and efficiency of an automotive engine. This article describes several processes used for identifying various additives (VI improvers, antioxidant, detergent, antifoaming, pour-point depressant involving differential and integral IR spectroscopy methods. Additive behavior during use is discussed along with how to control dosages in new oils. The technique proposed is characterized by its rapidity, by the small quantities of samples used (milliliters by the possibility of permanent control, and by being able to make a general diagnosis of the oil/engine system.

  15. Study of high density polyethylene under UV irradiation or mechanical stress by fluorescence spectroscopy; Etude du comportement du polyethylene haute densite sous irradiation ultraviolette ou sollicitation mecanique par spectroscopie de fluorescence

    Energy Technology Data Exchange (ETDEWEB)

    Douminge, L.

    2010-05-15

    Due to their diversity and their wide range of applications, polymers have emerged in our environment. For technical applications, these materials can be exposed to aggressive environment leading to an alteration of their properties. The effects of this degradation are linked to the concept of life duration, corresponding to the time required for a property to reach a threshold below which the material becomes unusable. Monitoring the ageing of polymer materials constitute a major challenge. Fluorescence spectroscopy is a technique able to provide accurate information concerning this issue. In this study, emphasis was placed on the use of fluorescence spectroscopy to study the phenomena involved in either the UV radiation or mechanical stresses of a polymer. In the case of high density polyethylene, the lack of intrinsic fluorescent signal leads to the use of a dye. This dye gives a fluorescent response depending on its microenvironment. All modifications in the macromolecular chain generate a shift of the fluorescent peak. This work can be dissociated in two major parts, on one hand the influence of UV aging on the fluorescent response and in another hand the influence of mechanical stresses. In the first part, complementary analyses like FTIR or DSC are used to correlate fluorescent results with known photo degradation mechanisms. The results show the great sensibility of the technique to the microstructural rearrangement in the polymer. In the second part, the dependence between the stress and the fluorescence emission gives opportunity to evaluate internal stresses in the material during cyclic solicitations. (author)

  16. Phase alteration compensation in reflection digital holography

    International Nuclear Information System (INIS)

    Rincon, O; Amezquita, R; Monroy, F

    2011-01-01

    The phase maps obtained from digital holographic microscopy techniques carry information about the axial lengths of the object under study. Additionally, these phase maps have information of tilt and curvatures with origin in the off-axis geometry and the magnification lenses system, respectively. Only a complete compensation of these extra phases allows a correct interpretation of the phase information. In this article a numerical strategy to compensate for these alterations is designed, using a phase mask located in different planes. This strategy is applied in the measurement of a phase steps plate using a digital holography setup.

  17. Ethic's pedagogy: from responsibility to alterity

    Directory of Open Access Journals (Sweden)

    Eduardo S. Vila Merino

    2004-11-01

    Full Text Available Ethics, since the so-called 'linguistic turn' and the rise of the notion of discursive formations, has tended to combine the teleological and the deontological. That means that, if ethics is to be useful in understanding relationships and other social issues, or in building the common good, it ought to take a procedural position. We believe that the teaching of ethics should be based on the notions of responsibility and alterity. These two concepts are helpful in promoting mutual understanding and other-directedness.

  18. Clerics urge ban on altering germline cells.

    Science.gov (United States)

    Norman, C

    1983-06-24

    A resolution calling for a ban on genetic engineering of human reproductive cells has been signed by leaders of almost every major church group in the United States. Some of the religious leaders, while not certain that a total moratorium should be placed on altering germline cells, signed the statement in order to stimulate public debate on the issue. Legislation has recently been introduced in Congress to set up a committee to monitor genetic engineering and its human applications, but author Jeremy Rifkin, the impetus behind the church leaders' resolution, argues that such tampering threatens the gene pool and should be banned altogether.

  19. Alterations of 5-Hydroxymethylcytosine in Human Cancers

    Directory of Open Access Journals (Sweden)

    Ali Yesilkanal

    2013-06-01

    Full Text Available Prior to 2009, 5-methylcytosine (5-mC was thought to be the only biologically significant cytosine modification in mammalian DNA. With the discovery of the TET enzymes, which convert 5-methylcytosine (5-mC to 5-hydroxymethylcytosine (5-hmC, however, intense interest has emerged in determining the biological function of 5-hmC. Here, we review the techniques used to study 5-hmC and evidence that alterations to 5-hmC physiology play a functional role in the molecular pathogenesis of human cancers.

  20. A powerful enhancement to the DMAP alter capability

    Science.gov (United States)

    Pamidi, P. R.

    1989-01-01

    A powerful enhancement to the DMAP alter capability was developed and is available on all RPK-supported versions of COSMIC/NASTRAN. This enhancement involves the addition of two alter control cards, called INSERT and DELETE, to the Executive Control Deck. These cards allow for DMAP alters to be made by referencing DMAP statements by their module names rather than by their statement numbers in the rigid format DMAP sequence. This allows for increased user convenience and flexibility and makes alters more meaningful to the user. In addition, DMAP alter packages employing the alter control cards will be much less susceptible to future changes in rigid format DMAPs than alter packages employing the standard ALTER control cards. The usage of the cards is illustrated by examples.

  1. 28 CFR 36.404 - Alterations: Elevator exemption.

    Science.gov (United States)

    2010-07-01

    ... 28 Judicial Administration 1 2010-07-01 2010-07-01 false Alterations: Elevator exemption. 36.404... Alterations: Elevator exemption. (a) This section does not require the installation of an elevator in an... facility has an elevator. ...

  2. Morphology of altered layers of glasses

    Energy Technology Data Exchange (ETDEWEB)

    Deruelle, O. [CEA Saclay, Dept. d' Astrophysique, de Physique des Particules, de Physique Nucleaire et de l' Instrumentation Associee, 91 - Gif sur Yvette (France); Spalla, O.; Lambard, J. [CEA Saclay, Dept. de Recherche sur l' Etat Condense les Atomes et les Molecules, 91 - Gif sur Yvette (France); Barboux, Ph.; Ricol, St. [Ecole Polytechnique, PMC, 91 - Palaiseau (France); Ricol, St.; Vernaz, E. [CEA Valrho, Dir. de l' Energie Nucleaire, DEN, 30 - Marcoule (France)

    1997-07-01

    The alteration of the french nuclear waste glass R7T7 has been studied through chemical analysis, thermo-poro-metry and X-ray scattering. Pseudo-dynamic leaching was used, with daily renewal of the leaching solution. The behavior of the R77 glass has been compared to cesium borosilicate glasses with small amounts of Ca and Zr added. As compared to these simplified compositions, the R7T7 glass has a quasi-congruent leaching of Na, B and Si and strongly retains Ca and Zr. The altered layers are very porous (porosity > 40% ). The pore size increases with time to reach a constant value that is independent of the nature of the glass but that strongly depends on the method used for leaching. The pore radii are about 4 nm in pseudo-dynamic mode and 2 nm in static conditions. X-ray scattering indicate that the pores are compact with a sharp interface. Their origin is related to the quasi-equilibrium reaction of hydrolysis redeposition of silica. (authors)

  3. Origins of altered reinforcement effects in ADHD

    Directory of Open Access Journals (Sweden)

    Tripp Gail

    2009-02-01

    Full Text Available Abstract Attention-deficit/hyperactivity disorder (ADHD, characterized by hyperactivity, impulsiveness and deficient sustained attention, is one of the most common and persistent behavioral disorders of childhood. ADHD is associated with catecholamine dysfunction. The catecholamines are important for response selection and memory formation, and dopamine in particular is important for reinforcement of successful behavior. The convergence of dopaminergic mesolimbic and glutamatergic corticostriatal synapses upon individual neostriatal neurons provides a favorable substrate for a three-factor synaptic modification rule underlying acquisition of associations between stimuli in a particular context, responses, and reinforcers. The change in associative strength as a function of delay between key stimuli or responses, and reinforcement, is known as the delay of reinforcement gradient. The gradient is altered by vicissitudes of attention, intrusions of irrelevant events, lapses of memory, and fluctuations in dopamine function. Theoretical and experimental analyses of these moderating factors will help to determine just how reinforcement processes are altered in ADHD. Such analyses can only help to improve treatment strategies for ADHD.

  4. Hemorheological alterations related to training and overtraining.

    Science.gov (United States)

    Brun, Jean-Frédéric; Varlet-Marie, Emmanuelle; Connes, Philippe; Aloulou, Ikram

    2010-01-01

    Alterations of blood rheology related to muscular activity have been extensively studied over the last 20 years. It has been shown that exercise exerts a "triphasic" action on the rheological properties of blood. In the short term, exercise induces a transient hyperviscosity, mostly due to a rise in hematocrit and plasma viscosity, but also to alterations in erythrocyte rheology. Reversal of this hyperviscosity pattern over the following 24 h can be described as an "autohemodilution". Later, training results in several profiles of "hemorheologic fitness" with a low hematocrit reflecting an expansion in plasma volume, and improvements in red cell rheology (increased deformability, decreased aggregation, reduced disaggregation shear rate). Some specific aspects of these long-term adaptations have been described, such as the intriguing occurrence of a paradoxical improvement in RBC deformability during exercise in some athletes, and overtraining, which is associated with higher plasma viscosity. Given the variety of modes of exercise and the wide heterogeneity of their effects on blood rheology in the short and long term, many investigations remain to be performed in this area of clinical hemorheology.

  5. Auditory alterations for occupational exposition in musicians

    Directory of Open Access Journals (Sweden)

    Melo, Ana Dolores Passarelli

    2008-09-01

    Full Text Available Introduction: Exposure to music has become an interest among experts in hearing and acoustics, once it's related to the professional and social activity and to the high prevalence of Hearing Loss. Objective: To investigate musicians auditory health. Method: 30 musicians participated in the study and were submitted to specific interview, conventional and highfrequency tonal audiometry, tympanometry and transient-evoked and distortion-produced otoacoustic emissions. Results: 17% of the participants presented an audiogram that suggested Noise-Induced Hearing Loss, 7% normal with notch and 7% with other characteristics. The frequency thresholds average of 3, 4 and 6kHz presented a more intense level when compared to the one of 500, 1 and 2kHz; as well as the high frequency audiometry thresholds average when compared to the conventional audiometry. There was a threshold positive correlation with the age and time of profession. There hasn't been found transiently evoked otoacoustic emissions in 26,7% (right ear and 23,3% (left ear, as well as in isolated frequencies in distortion-produced evoked otoacoustic emissions. Conclusion: Alterations were observed in tests with no complaints of hearing difficulties; the otoacoustic emissions test presented more sensitivity in the early detection of hearing alterations; musicians present a significant risk of developing hearing loss.

  6. Plants altering hormonal milieu: A review

    Directory of Open Access Journals (Sweden)

    Prashant Tiwari

    2017-02-01

    Full Text Available The aim of the present review article is to investigate the herbs which can alter the levels of hormones like Follicle stimulating hormone, Prolactin, Growth hormone, Insulin, Thyroxine, Estrogen, Progesterone, Testosterone, and Relaxin etc. Hormones are chemical signal agents produced by different endocrine glands for regulating our biological functions. The glands like pituitary, thyroid, adrenal, ovaries in women and testes in men all secrete a number of hormones with different actions. However, when these hormones are perfectly balanced then people become healthy and fit. But several factors like pathophysiological as well as biochemical changes, disease conditions, changes in the atmosphere, changes in the body, diet changes etc. may result in imbalance of various hormones that produce undesirable symptoms and disorders. As medicinal plants have their importance since ancient time, people have been using it in various ways as a source of medicine for regulation of hormonal imbalance. Moreover, it is observed that certain herbs have a balancing effect on hormones and have great impact on well-being of the people. So, considering these facts we expect that the article provides an overview on medicinal plants with potential of altering hormone level.

  7. Thermal remediation alters soil properties - a review.

    Science.gov (United States)

    O'Brien, Peter L; DeSutter, Thomas M; Casey, Francis X M; Khan, Eakalak; Wick, Abbey F

    2018-01-15

    Contaminated soils pose a risk to human and ecological health, and thermal remediation is an efficient and reliable way to reduce soil contaminant concentration in a range of situations. A primary benefit of thermal treatment is the speed at which remediation can occur, allowing the return of treated soils to a desired land use as quickly as possible. However, this treatment also alters many soil properties that affect the capacity of the soil to function. While extensive research addresses contaminant reduction, the range and magnitude of effects to soil properties have not been explored. Understanding the effects of thermal remediation on soil properties is vital to successful reclamation, as drastic effects may preclude certain post-treatment land uses. This review highlights thermal remediation studies that have quantified alterations to soil properties, and it supplements that information with laboratory heating studies to further elucidate the effects of thermal treatment of soil. Notably, both heating temperature and heating time affect i) soil organic matter; ii) soil texture and mineralogy; iii) soil pH; iv) plant available nutrients and heavy metals; v) soil biological communities; and iv) the ability of the soil to sustain vegetation. Broadly, increasing either temperature or time results in greater contaminant reduction efficiency, but it also causes more severe impacts to soil characteristics. Thus, project managers must balance the need for contaminant reduction with the deterioration of soil function for each specific remediation project. Copyright © 2017 Elsevier Ltd. All rights reserved.

  8. [Hepatic alterations in patients with dengue].

    Science.gov (United States)

    Larreal, Yraima; Valero, Nereida; Estévez, Jesús; Reyes, Ivette; Maldonado, Mery; Espina, Luz Marina; Arias, Julia; Meleán, Eddy; Añez, German; Atencio, Ricardo

    2005-06-01

    Clinical features of Dengue are very variable due to multiple alterations induced by the virus in the organism. Increased levels of transaminases similar to those produced by the Hepatitis virus have been reported in patients with Dengue from hiperendemic zones in Asia. The objectives of this study were to determine alterations in the liver tests in patients with Dengue and to relate them to the disease, clinically and serologically. Clinical history, hemathological tests serum transaminases (ALT y AST) and bilirubin assays were performed in 62 patients with clinical and serological diagnosis of Dengue. According to clinical features 38.7% of the patients with classical (CD) and hemorrhagic (DHF) forms of Dengue reffered abdominal pain and 2 patients with DHF had ictericia and hepatomegaly. Laboratory test findings showed leucopenia in 72.5% in both forms of Dengue and of patients with DHF severe thrombocytopenia (< 50.000 platelets x mm3), long PT and PPT in 70.9%, 23.0% and 42.3%, respectively. Transaminase values five fold higher than the normal values (p < 0.005) were observed in 36.8% and 74.4% of patients with CD and DHF respectively; AST was predominant in both groups. Our results suggest liver damage during the course of Dengue. A differential diagnosis has to be done between the hepatic involvement of Dengue cases and others viral diseases with hepatic disfunctions.

  9. Altered pharyngeal muscles in Parkinson disease.

    Science.gov (United States)

    Mu, Liancai; Sobotka, Stanislaw; Chen, Jingming; Su, Hungxi; Sanders, Ira; Adler, Charles H; Shill, Holly A; Caviness, John N; Samanta, Johan E; Beach, Thomas G

    2012-06-01

    Dysphagia (impaired swallowing) is common in patients with Parkinson disease (PD) and is related to aspiration pneumonia, the primary cause of death in PD. Therapies that ameliorate the limb motor symptoms of PD are ineffective for dysphagia. This suggests that the pathophysiology of PD dysphagia may differ from that affecting limb muscles, but little is known about potential neuromuscular abnormalities in the swallowing muscles in PD. This study examined the fiber histochemistry of pharyngeal constrictor and cricopharyngeal sphincter muscles in postmortem specimens from 8 subjects with PD and 4 age-matched control subjects. Pharyngeal muscles in subjects with PD exhibited many atrophic fibers, fiber type grouping, and fast-to-slow myosin heavy chain transformation. These alterations indicate that the pharyngeal muscles experienced neural degeneration and regeneration over the course of PD. Notably, subjects with PD with dysphagia had a higher percentage of atrophic myofibers versus with those without dysphagia and controls. The fast-to-slow fiber-type transition is consistent with abnormalities in swallowing, slow movement of food, and increased tone in the cricopharyngeal sphincter in subjects with PD. The alterations in the pharyngeal muscles may play a pathogenic role in the development of dysphagia in subjects with PD.

  10. Obesity Promotes Alterations in Iron Recycling

    Directory of Open Access Journals (Sweden)

    Marta Citelli

    2015-01-01

    Full Text Available Hepcidin is a key hormone that induces the degradation of ferroportin (FPN, a protein that exports iron from reticuloendothelial macrophages and enterocytes. The aim of the present study was to experimentally evaluate if the obesity induced by a high-fat diet (HFD modifies the expression of FPN in macrophages and enterocytes, thus altering the iron bioavailability. In order to directly examine changes associated with iron metabolism in vivo, C57BL/6J mice were fed either a control or a HFD. Serum leptin levels were evaluated. The hepcidin, divalent metal transporter-1 (DMT1, FPN and ferritin genes were analyzed by real-time polymerase chain reaction. The amount of iron present in both the liver and spleen was determined by flame atomic absorption spectrometry. Ferroportin localization within reticuloendothelial macrophages was observed by immunofluorescence microscopy. Obese animals were found to exhibit increased hepcidin gene expression, while iron accumulated in the spleen and liver. They also exhibited changes in the sublocation of splenic cellular FPN and a reduction in the FPN expression in the liver and the spleen, while no changes were observed in enterocytes. Possible explanations for the increased hepcidin expression observed in HFD animals may include: increased leptin levels, the liver iron accumulation or endoplasmic reticulum (ER stress. Together, the results indicated that obesity promotes changes in iron bioavailability, since it altered the iron recycling function.

  11. 46 CFR 115.700 - Permission for repairs and alterations.

    Science.gov (United States)

    2010-10-01

    ... replacement in kind, of electrical wiring, fuel lines, tanks, boilers and other pressure vessels, and steering... 46 Shipping 4 2010-10-01 2010-10-01 false Permission for repairs and alterations. 115.700 Section... AND CERTIFICATION Repairs and Alterations § 115.700 Permission for repairs and alterations. (a...

  12. Alterations in adipokines in feline hepatic lipidosis.

    Science.gov (United States)

    Mazaki-Tovi, M; Abood, S K; Segev, G; Schenck, P A

    2013-01-01

    Feline hepatic lipidosis (HL) is associated with alterations in lipid and carbohydrate metabolism. The adipokines, adiponectin, and leptin have lipid-lowering and insulin-sensitizing effects. Serum concentrations of adiponectin and leptin are altered in feline HL. Client-owned cats: 55 healthy and 45 with liver disease. Cats with liver disease were categorized as having HL (n = 20), HL and concurrent disease (n = 19), or other liver disease (n = 6), based on clinical signs, laboratory findings, abdominal ultrasound examination as well as liver cytopathology, histopathology, or both. Serum samples were collected and body condition score determined. Mean serum concentrations of adiponectin were higher in overweight cats with HL (4.5 μg/mL), HL and concurrent disease (4.4 μg/mL), or other liver disease (6.1 μg/mL), as compared with healthy cats (1.5 μg/mL; P < .001, P < .001, and P = .04, respectively). Mean serum concentration of leptin was higher in cats with HL (9.8 ng/mL) or HL and concurrent disease (10.7 ng/mL) than healthy cats (4.9 ng/mL, P < .001 and P < .001, respectively). Cats with other liver disease had leptin concentration (4.9 ng/mL) similar to healthy cats. Concentrations of adiponectin were correlated with alanine aminotransferase activity (r = 0.40, P = .0069), and concentrations of leptin were correlated with alkaline phosphatase activity (r = 0.42, P = .0051) in cats with liver disease. Adipokine concentrations are altered in feline HL. Increased concentrations of adiponectin are related to liver disease, whereas increased concentrations of leptin are specifically related to HL. Copyright © 2013 by the American College of Veterinary Internal Medicine.

  13. Alteration of serum adropin level in preeclampsia.

    Science.gov (United States)

    Wang, Huihua; Gao, Bo; Wu, Zaigui; Wang, Hanzhi; Dong, Minyue

    2017-04-01

    To clarify the alterations in serum adropin and preptin concentrations in preeclampsia, we determined serum adropin and preptin levels in 29 women with normal pregnancy and 32 women with preeclampsia. We found that maternal age, body mass index and fetal gender were not significantly different between two groups; however, blood pressure, gestational age and neonatal birth weight were significantly different. Serum adropin levels were significantly increased in women with preeclampsia compared with those with normal pregnancy but there were no significant differences in preptin levels. An increase in maternal serum adropin level was found in preeclampsia, and this may be a compensation for pregnancy complicated with preeclampsia. Copyright © 2017 International Society for the Study of Hypertension in Pregnancy. Published by Elsevier B.V. All rights reserved.

  14. Aqueous alteration detection in Tikhonravov crater, Mars

    Science.gov (United States)

    Mancarella, F.; Fonti, S.; Alemanno, G.; Orofino, V.; Blanco, A.

    2018-03-01

    The existence of a wet period lasting long enough to allow the development of elementary forms of life on Mars has always been a very interesting issue. Given this perspective, the research for geological markers of such occurrences has been continually pursued. Once a favorable site is detected, effort should be spent to get as much information as possible aimed at a precise assessment of the genesis and evolution of the areas showing the selected markers. In this work, we discuss the recent finding of possible deposits pointing to the past existence of liquid water in Tikhonravov crater located in Arabia Terra. Comparison of CRISM spectra and those of laboratory minerals formed by aqueous alteration has led us to the conclusion that the studied areas within the impact crater host phyllosilicates deposits. In addition, analysis of the CRISM spectra has resulted in the tentative identification of carbonates mixed with phyllosilicates.

  15. Oral complications of cancer therapies. Mucosal alterations

    Energy Technology Data Exchange (ETDEWEB)

    Squier, C.A. (Univ. of Iowa, Iowa City (USA))

    1990-01-01

    The initial effect of anticancer therapy, such as radiation and chemotherapy, is on the rapidly proliferating cells of the oral epithelium. As a consequence, the epithelium may show atrophy and ulceration. The sites of these alterations are related to the rate of epithelial proliferation. Regions of rapid proliferation, such as the oral lining mucosa, show a greater frequency of ulceration than masticatory mucosa or skin. Subsequent changes in the mucosa reflect damage to connective tissue, including fibroblasts and blood vessels. This results in hyalinization of collagen, hypovascularity, and ischemia. Indirect effects of anticancer therapy may include granulocytopenia and reduced salivary secretion, so that the protective mucin coating of the epithelium is compromised. These changes result in tissue with reduced barrier function and impaired ability to heal and to resist entry of pathogens, thus increasing the risk of systemic infections.

  16. Frontal lobe alterations in schizophrenia: a review.

    Science.gov (United States)

    Mubarik, Ateeq; Tohid, Hassaan

    2016-01-01

    To highlight the changes in the frontal lobe of the human brain in people with schizophrenia. This was a qualitative review of the literature. Many schizophrenic patients exhibit functional, structural, and metabolic abnormalities in the frontal lobe. Some patients have few or no alterations, while some have more functional and structural changes than others. Magnetic resonance imaging (MRI) shows structural and functional changes in volume, gray matter, white matter, and functional activity in the frontal lobe, but the mechanisms underlying these changes are not yet fully understood. When schizophrenia is studied as an essential topic in the field of neuropsychiatry, neuroscientists find that the frontal lobe is the most commonly involved area of the human brain. A clear picture of how this lobe is affected in schizophrenia is still lacking. We therefore recommend that further research be conducted to improve understanding of the pathophysiology of this psychiatric dilemma.

  17. Bortezomib alters sour taste sensitivity in mice

    Directory of Open Access Journals (Sweden)

    Akihiro Ohishi

    Full Text Available Chemotherapy-induced taste disorder is one of the critical issues in cancer therapy. Bortezomib, a proteasome inhibitor, is a key agent in multiple myeloma therapy, but it induces a taste disorder. In this study, we investigated the characteristics of bortezomib-induced taste disorder and the underlying mechanism in mice. Among the five basic tastes, the sour taste sensitivity of mice was significantly increased by bortezomib administration. In bortezomib-administered mice, protein expression of PKD2L1 was increased. The increased sour taste sensitivity induced by bortezomib returned to the control level on cessation of its administration. These results suggest that an increase in protein expression of PKD2L1 enhances the sour taste sensitivity in bortezomib-administered mice, and this alteration is reversed on cessation of its administration. Keywords: Taste disorder, Bortezomib, Sour taste, Chemotherapy, Adverse effect

  18. Alterations in subspecific characters of groundnut

    International Nuclear Information System (INIS)

    Mouli, C.; Patil, S.H.; Kale, D.M.

    1983-01-01

    Recombination of beneficial characters associated in the cultivars of groundnut (Arachis hypogaea, L.) belonging to the two subspecies hypogaea and fastigiata had little success in conventional breeding programme. The cultures of ssp. hypogaea have the desirable characters for the crop improvement viz; various growth habits, profuse branching, large pod, seed dormancy and stress tolerance. Sequential flowering, early maturity, compact fruiting habit and high kernel outturn are the other useful characters present in ssp. fastigiata cultures. Mutation research in a popular variety, Spanish Improved belonging to ssp. fastigiata led to the selection of various mutants. One among the mutants had large pod, a characteristic of hypogaea ssp. Hybridization among the mutants and improved cultivars as well as radiation treatment of selected cultures resulted in the isolation of cultures having not only combinations and alterations of characters in both subspecies, but also modifications. These cultures are classified into major groups and their significance in the groundnut improvement is discussed. (author)

  19. DNA methylation alterations in Alzheimer's disease.

    Science.gov (United States)

    Yokoyama, Amy S; Rutledge, John C; Medici, Valentina

    2017-05-01

    The observation that Alzheimer's disease (AD) patients with similar and even identical genetic backgrounds often present with heterogeneous pathologies has prompted the hypothesis that epigenetics may contribute to AD. While the study of epigenetics encompasses a variety of modifications including histone modifications and non-coding RNAs, much of the research on how epigenetics might impact AD pathology has been focused on DNA methylation. To this end, several studies have characterized DNA methylation alterations in various brain regions of individuals with AD, with conflicting results. This review examines the results of studies analyzing both global and gene-specific DNA methylation changes in AD and also assesses the results of studies analyzing DNA hydroxymethylation in patients with AD.

  20. Saccadic Alterations in Severe Developmental Dyslexia

    Directory of Open Access Journals (Sweden)

    Stefano Pensiero

    2013-01-01

    Full Text Available It is not sure if persons with dyslexia have ocular motor deficits in addition to their deficits in rapid visual information processing. A 15-year-old boy afflicted by severe dyslexia was submitted to saccadic eye movement recording. Neurological and ophthalmic examinations were normal apart from the presence of an esophoria for near and slightly longer latencies of pattern visual evoked potentials. Subclinical saccadic alterations were present, which could be at the basis of the reading pathology: (1 low velocities (and larger durations of the adducting saccades of the left eye with undershooting and long-lasting postsaccadic onward drift, typical of the internuclear ophthalmoplegia; (2 saccades interrupted in mid-flight and fixation instability, which are present in cases of brainstem premotor disturbances.

  1. Altered erythrocyte cation permeability in familial pseudohyperkalaemia.

    Science.gov (United States)

    Dagher, G; Vantyghem, M C; Doise, B; Lallau, G; Racadot, A; Lefebvre, J

    1989-08-01

    1. Erythrocyte cation transport pathways have been investigated in a family with pseudohyperkalaemia. 2. Ouabain- and bumetanide-resistant Na+ and K+ effluxes in three pseudohyperkalaemic patients were not different from those of control subjects when assessed at 37 degrees C. 3. When the temperature was decreased to 20 degrees C and 9 degrees C, K+ passive permeability markedly increased and Na+ permeability remained unchanged in these patients. In contrast, in control subjects a reduction in temperature caused a marked reduction in Na+ and K+ passive permeability. 4. These findings could account for the marked increase in plasma K+ concentration observed at subphysiological temperatures. 5. The Na+-K+ co-transport pathway was reduced in all members of the family, but the Na+-K+ pump was reduced in only two of them. These alterations were independent from the pseudohyperkalaemic state.

  2. Peripheral myelin protein 22 alters membrane architecture

    Science.gov (United States)

    Mittendorf, Kathleen F.; Marinko, Justin T.; Hampton, Cheri M.; Ke, Zunlong; Hadziselimovic, Arina; Schlebach, Jonathan P.; Law, Cheryl L.; Li, Jun; Wright, Elizabeth R.; Sanders, Charles R.; Ohi, Melanie D.

    2017-01-01

    Peripheral myelin protein 22 (PMP22) is highly expressed in myelinating Schwann cells of the peripheral nervous system. PMP22 genetic alterations cause the most common forms of Charcot-Marie-Tooth disease (CMTD), which is characterized by severe dysmyelination in the peripheral nerves. However, the functions of PMP22 in Schwann cell membranes remain unclear. We demonstrate that reconstitution of purified PMP22 into lipid vesicles results in the formation of compressed and cylindrically wrapped protein-lipid vesicles that share common organizational traits with compact myelin of peripheral nerves in vivo. The formation of these myelin-like assemblies depends on the lipid-to-PMP22 ratio, as well as on the PMP22 extracellular loops. Formation of the myelin-like assemblies is disrupted by a CMTD-causing mutation. This study provides both a biochemical assay for PMP22 function and evidence that PMP22 directly contributes to membrane organization in compact myelin. PMID:28695207

  3. Glaucoma alters the circadian timing system.

    Directory of Open Access Journals (Sweden)

    Elise Drouyer

    Full Text Available Glaucoma is a widespread ocular disease and major cause of blindness characterized by progressive, irreversible damage of the optic nerve. Although the degenerative loss of retinal ganglion cells (RGC and visual deficits associated with glaucoma have been extensively studied, we hypothesize that glaucoma will also lead to alteration of the circadian timing system. Circadian and non-visual responses to light are mediated by a specialized subset of melanopsin expressing RGCs that provide photic input to mammalian endogenous clock in the suprachiasmatic nucleus (SCN. In order to explore the molecular, anatomical and functional consequences of glaucoma we used a rodent model of chronic ocular hypertension, a primary causal factor of the pathology. Quantitative analysis of retinal projections using sensitive anterograde tracing demonstrates a significant reduction (approximately 50-70% of RGC axon terminals in all visual and non-visual structures and notably in the SCN. The capacity of glaucomatous rats to entrain to light was challenged by exposure to successive shifts of the light dark (LD cycle associated with step-wise decreases in light intensity. Although glaucomatous rats are able to entrain their locomotor activity to the LD cycle at all light levels, they require more time to re-adjust to a shifted LD cycle and show significantly greater variability in activity onsets in comparison with normal rats. Quantitative PCR reveals the novel finding that melanopsin as well as rod and cone opsin mRNAs are significantly reduced in glaucomatous retinas. Our findings demonstrate that glaucoma impacts on all these aspects of the circadian timing system. In light of these results, the classical view of glaucoma as pathology unique to the visual system should be extended to include anatomical and functional alterations of the circadian timing system.

  4. Wound trauma alters ionizing radiation dose assessment

    Directory of Open Access Journals (Sweden)

    Kiang Juliann G

    2012-06-01

    Full Text Available Abstract Background Wounding following whole-body γ-irradiation (radiation combined injury, RCI increases mortality. Wounding-induced increases in radiation mortality are triggered by sustained activation of inducible nitric oxide synthase pathways, persistent alteration of cytokine homeostasis, and increased susceptibility to bacterial infection. Among these factors, cytokines along with other biomarkers have been adopted for biodosimetric evaluation and assessment of radiation dose and injury. Therefore, wounding could complicate biodosimetric assessments. Results In this report, such confounding effects were addressed. Mice were given 60Co γ-photon radiation followed by skin wounding. Wound trauma exacerbated radiation-induced mortality, body-weight loss, and wound healing. Analyses of DNA damage in bone-marrow cells and peripheral blood mononuclear cells (PBMCs, changes in hematology and cytokine profiles, and fundamental clinical signs were evaluated. Early biomarkers (1 d after RCI vs. irradiation alone included significant decreases in survivin expression in bone marrow cells, enhanced increases in γ-H2AX formation in Lin+ bone marrow cells, enhanced increases in IL-1β, IL-6, IL-8, and G-CSF concentrations in blood, and concomitant decreases in γ-H2AX formation in PBMCs and decreases in numbers of splenocytes, lymphocytes, and neutrophils. Intermediate biomarkers (7 – 10 d after RCI included continuously decreased γ-H2AX formation in PBMC and enhanced increases in IL-1β, IL-6, IL-8, and G-CSF concentrations in blood. The clinical signs evaluated after RCI were increased water consumption, decreased body weight, and decreased wound healing rate and survival rate. Late clinical signs (30 d after RCI included poor survival and wound healing. Conclusion Results suggest that confounding factors such as wounding alters ionizing radiation dose assessment and agents inhibiting these responses may prove therapeutic for radiation combined

  5. Microbiome, inflammation, epigenetic alterations, and mental diseases.

    Science.gov (United States)

    Alam, Reza; Abdolmaleky, Hamid M; Zhou, Jin-Rong

    2017-09-01

    Major mental diseases such as autism, bipolar disorder, schizophrenia, and major depressive disorder are debilitating illnesses with complex etiologies. Recent findings show that the onset and development of these illnesses cannot be well described by the one-gene; one-disease approach. Instead, their clinical presentation is thought to result from the regulative interplay of a large number of genes. Even though the involvement of many genes are likely, up regulating and activation or down regulation and silencing of these genes by the environmental factors play a crucial role in contributing to their pathogenesis. Much of this interplay may be moderated by epigenetic changes. Similar to genetic mutations, epigenetic modifications such as DNA methylation, histone modifications, and RNA interference can influence gene expression and therefore may cause behavioral and neuronal changes observed in mental disorders. Environmental factors such as diet, gut microbiota, and infections have significant role in these epigenetic modifications. Studies show that bioactive nutrients and gut microbiota can alter either DNA methylation and histone signatures through a variety of mechanisms. Indeed, microbes within the human gut may play a significant role in the regulation of various elements of "gut-brain axis," via their influence on inflammatory cytokines and production of antimicrobial peptides that affect the epigenome through their involvement in generating short chain fatty acids, vitamin synthesis, and nutrient absorption. In addition, they may participate in-gut production of many common neurotransmitters. In this review we will consider the potential interactions of diet, gastrointestinal microbiome, inflammation, and epigenetic alterations in psychiatric disorders. © 2017 Wiley Periodicals, Inc.

  6. Development of a Matrix Alteration Model (MAM)

    International Nuclear Information System (INIS)

    Martinez Esparza, A.; Cunado, M. A.; Gago, J. A.; Quinones, J.; Iglesias, E.; Cobos, J.; Gonzalez de la Huebra, A.; Cera, E.; Merino, J.; Bruno, J.; Pablos, J. de; Casas, I.; Clarens, F.; Gimenez, J.

    2005-01-01

    The present report is a summary of the main tasks carried out within the WP4 of the SFS project (5th Framework Programme of the European Commission) by ENRESA and collaborators, mainly focused on the development of the so-called Matrix Alteration Model (MAM), a model to study the long-term oxidant dissolution of the spent fuel matrix under repository conditions. A variety of issues have been addressed: development of the MAM conceptual model, integration of a new matrix alteration mechanism in the radiolytic model, calibration and testing of the model, calculations for base case in Performance Assessment exercises, sensitivity analysis and an assessment of applicability of the MAM. The conceptual model for the UO2 oxidant dissolution is based on the processes expected to occur in the long term under repository conditions. Briefly, when water will enter in contact with the fuel surface, the first process we may expect is the radiolysis of water. Water radiolysis will generate reductant and oxidants and we may expect local oxidising conditions. Because of these local conditions, the surface of the fuel will be oxidized. The oxidation of the matrix and the attachment of aqueous ligands able to form strong complexes with its major component will favour the dissolution of the matrix. The integration of the matrix alteration (oxidation and dissolution) mechanism in the radiolytic model by means of elemental reactions has been mainly elucidated from the mechanistic models developed for non-irradiated UO2 dissolution experiments. Moreover, flow-through dissolution experiments with unirradiated UO2 have been used to calibrate the oxidative dissolution mechanism of UO2. The model developed has been able to reproduce experimental dissolution rates for pH > 5 and [HCO3 -] < 10-2 M when the oxidant is O2 at partial pressures lower than 21%, and 3 < pH < 9 and [HCO3 -] = 210-3 M and when the oxidant is H2O2 at concentrations below 10-4 M. These ranges cover the geochemical

  7. Smectite alteration by anaerobic iron corrosion

    International Nuclear Information System (INIS)

    Sanders, D.; Kaufhold, S.; Hassel, A.W.; Dohrmann, R.

    2010-01-01

    Document available in extended abstract form only. The interaction of smectites with corroding steel/iron represents a crucial topic in the estimation of the long term confinement properties of clay barriers for the encasement of steel/iron containers. Especially in case of engineered clay barriers a possible deterioration of favourable smectite properties as response to corrosion could reduce the barrier capacity. The extent of this reduction is unknown, yet. The essential properties of bentonite clays in this context are on the one hand the relatively high swelling pressure together with low hydraulic conductivity, which results from the well known expandability of smectite interlayers in aqueous environments. On the other hand smectites are cation exchangers being able to long term encase radioactive cations in a way that negative charges of silicate layers are compensated by easily exchangeable hydrated cations. Both properties are directly related to the crystal and chemical composition of smectites. The nature of the corrosion of steel canisters in clay barriers will - after a first short aerobic phase - predominantly be anaerobic resulting in the formation of Fe(II) and two equivalents of hydroxide ions. In a set of exposition experiments anaerobic corroding iron in bentonite gels was studied in order to determine alteration of the smectite fraction. During the exposition a green coloration of the bentonite neighbouring to corroding iron was observed. Upon contact to oxygen in a humid state the bentonite turned reddish indicating the oxidation of Fe(II) to Fe(III). This observation is in accordance with reported results indicating the formation of an iron rich smectite. Chemical analysis of the 'green bentonite' reveals an increase of iron fraction e.g. from 3.4% mass to 9.3% mass . The adsorbed iron is predominantly Fe(II) which was proven by chromato-metric titration. The estimated ratio between silicon to increased iron content is Si: Fe ≅ 2

  8. Near-field/altered-zone models report

    Energy Technology Data Exchange (ETDEWEB)

    Hardin, E. L., LLNL

    1998-03-01

    nonlithophysal and lower lithophysal units. These units are made up of moderately to densely welded, devitrified, fractured tuff. The rock's chemical composition is comparable to that of typical granite, but has textural features and mineralogical characteristics of large-scale, silicic volcanism. Because the repository horizon will be approximately 300 m below the ground surface and 200 m above the water table, the repository will be partially saturated. The welded tuff matrix in the host units is highly impermeable, but water and gas flow readily through fractures. The degree of fracturing in these units is highly variable, and the hydrologic significance of fracturing is an important aspect of site investigation. This report describes the characterization and modeling of a region around the potential repository--the altered zone--a region in which the temperature will be increased significantly by waste-generated heat. Numerical simulation has shown that, depending on the boundary conditions, rock properties, and repository design features incorporated in the models, the altered zone (AZ) may extend from the water table to the ground surface. This report also describes models of the near field, the region comprising the repository emplacement drifts and the surrounding rock, which are critical to the performance of engineered components. Investigations of near-field and altered-zone (NF/AZ) processes support the design of underground repository facilities and engineered barriers and also provide constraint data for probabilistic calculations of waste-isolation performance (i.e., performance assessment). The approach to investigation, which is an iterative process involving hypothesis testing and experimentation, has relied on conceptualizing engineered barriers and on performance analysis. This report is a collection, emphasizing conceptual and numerical models, of the recent results contributed from studies of NF/AZ processes and of quantitative measures of NF

  9. Genetic alterations and epigenetic changes in hepatocarcinogenesis

    Directory of Open Access Journals (Sweden)

    Luz Stella Hoyos Giraldo

    2007-02-01

    Full Text Available

    Hepatocarcinogenesis as hepatocellular carcinoma (HCC is associated with background of chronic liver disease usually in association with cirrhosis, marked hepatic fibrosis, hepatitis B virus (HBV and/or hepatitis virus (HCV infection, chronic inflammation, Aflatoxin B1(AFB1 exposure, chronic alcoholism, metabolic disorder of the liver and necroinflamatory liver disease. Hepatocarcinogenesis involve two mechanisms, genetic alterations (with changes in the cell's DNA sequence and epigenetic changes (without changes in the cell's DNA sequence, but changes in the pattern of gene expression that can persist through one or more generations (somatic sense. Hepatocarcinogenesis is associated with activation of oncogenes and decreased expression of tumor suppressor genes (TSG; include those involved in cell cycle control, apoptosis, DNA repair, immortalization and angiogenesis. AFB1 is metabolized in the liver into a potent carcinogen, aflatoxin 8, 9-epoxide, which is detoxified by epoxide hydrolase (EPHX and glutathione S-transferase M1 (GSTM1.

    A failure of detoxification processes can allow to mutagenic metabolite to bind to DNA and inducing P53 mutation. Genetic polymorphism of EPHX and GSTM1 can make individuals more susceptible to AFB1. Epigenetic inactivation of GSTP1 by promoter hypermethylation plays a role in the development of HCC because, it leads that electrophilic metabolite increase DNA damage and mutations. HBV DNA integration into the host chromosomal DNA of hepatocytes has been detected in HBV-related HCC.

    DNA tumor viruses cause cancer mainly by interfering with cell cycle controls, and activating the cell's replication machinery by blocking the action of key TSG. HBx protein is a

  10. Iron status alters murine systemic lupus erythematosus.

    Science.gov (United States)

    Leiter, L M; Reuhl, K R; Racis, S P; Sherman, A R

    1995-03-01

    The effect of Fe status on murine systemic lupus erythematosus was investigated. Weanling female MRL/MPJ-lpr/lpr mice (systemic lupus erythematosus strain) were fed diets with the following levels (mg Fe/kg diet): 3 (severely deficient), 10 (moderately deficient), 35 (control) and 250 (supplemented). A fifth group was pair fed the control diet in the amounts consumed by the severely deficient group. C3H/Hej mice fed the same diets were used as non-lupus controls. Anemia was more severe in severely deficient mice than in all other MRL groups and C3H severely deficient mice. Incidence of skin lesions was highest in MRL severely and moderately deficient mice compared with pair-fed, control and supplemented mice. By 22 wk of age, mortality was higher in supplemented and severely deficient mice than in moderately deficient, pair-fed and control MRL mice. Anti-dsDNA activity in serum was not altered by Fe. In a second experiment, kidney function was examined in mice fed severely deficient, control, supplemented and pair-fed diets. Urine protein concentration was highest in supplemented mice at 14 wk of age. Serum urea nitrogen was significantly higher in MRL severely deficient mice than in pair-fed and control mice at 18 wk of age. Glomerular filtration rate, measured by creatinine clearance, was significantly lower in MRL severely deficient mice than in pair-fed and Fe supplemented mice at 16 wk of age and pair-fed and control mice at 18 wk of age. Renal histopathology was more severe in Fe supplemented mice than in pair-fed and control mice, and more severe in severely deficient and pair-fed mice than in control mice. Fluorescent staining of kidneys with anti-Ig G and anti-C3 fluorescein-conjugated antibodies was most intense in severely deficient mice, and the concentration of circulating immune complexes in serum was significantly higher in severely deficient mice than in all other groups. These data demonstrate that systemic lupus erythematosus in MRL

  11. Pyrogenic organic matter can alter microbial communication

    Science.gov (United States)

    Masiello, Caroline; Gao, Xiaodong; Cheng, Hsiao-Ying; Silberg, Jonathan

    2016-04-01

    Soil microbes communicate with each other to manage a large range of processes that occur more efficiently when microbes are able to act simultaneously. This coordination occurs through the continuous production of signaling compounds that are easily diffused into and out of cells. As the number of microbes in a localized environment increases, the internal cellular concentration of these signaling compounds increases, and when a threshold concentration is reached, gene expression shifts, leading to altered (and coordinated) microbial behaviors. Many of these coordinated behaviors have biogeochemically important outcomes. For example, methanogenesis, denitrification, biofilm formation, and the development of plant-rhizobial symbioses are all regulated by a simple class of cell-cell signaling molecules known as acyl homoserine lactones (AHLs). Pyrogenic organic matter in soils can act to disrupt microbial communication through multiple pathways. In the case of AHLs, charcoal's very high surface area can sorb these signaling compounds, preventing microbes from detecting each others' presence (Masiello et al., 2014). In addition, the lactone ring in AHLs is vulnerable to pH increases accompanying PyOM inputs, with soil pH values higher than 7-8 leading to ring opening and compound destabilization. Different microbes use different classes of signaling compounds, and not all microbial signaling compounds are pH-vulnerable. This implies that PyOM-driven pH increases may trigger differential outcomes for Gram negative bacteria vs fungi, for example. A charcoal-driven reduction in microbes' ability to detect cell-cell communication compounds may lead to a shift in the ability of microbes to participate in key steps of C and N cycling. For example, an increase in an archaeon-specific AHL has been shown to lead to a cascade of metabolic processes that eventually results in the upregulation of CH4 production (Zhang et al., 2012). Alterations in similar AHL compounds leads to

  12. « Comment se comporter avec un roi chrétien » : l’ouvrage perdu d’Abū l-Ḥasan ʿAlī Ibn al-Qaṭṭān et les enjeux du cérémonial almohade

    Directory of Open Access Journals (Sweden)

    Mehdi Ghouirgate

    2014-05-01

    Full Text Available Cet article propose de revenir sur un document aussi exceptionnel que méconnu. Il s’agit du résumé d’un ouvrage (maqāla, aujourd’hui perdu, intitulé « Comment se comporter avec un roi chrétien », et que l’on trouve dans le dictionnaire bio-bibliographique d’Ibn ʿAbd al-Malik. Cette maqāla fut rédigée, par un homme de lettres au service des Almohades, Abū l-Ḥasan ʿAlī Ibn al-Qaṭṭān (m. 1231. C’est la seule source qui ait consigné des indications sur la conduite que devait adopter le souverain lors d’une cérémonie, en présence d’un prince étranger. À ce titre, on y trouve des renseignements essentiels sur le cérémonial almohade ainsi que sur les dilemmes que devaient résoudre le calife : d’un point de vue idéologique, il ne pouvait souffrir aucun autre pouvoir, mais l’impossibilité de mener des opérations d’envergure sur deux fronts à la fois l’amena à composer avec le roi du León. De même, c’est le seul document à avoir fait état d’une divergence de point de vue entre le calife et les intellectuels organiques du système, les Ṭalaba. Ce différend met en lumière des tensions latentes au sommet entre divers serviteurs de l’État, qui n’avaient pas la même forme de légitimité, ni tout à fait les mêmes intérêts.

  13. Soudage par explosion thermique sous charge de cermets poreux à base de TiC-Ni sur substrat en acier-comportement tribologique Welding of porous TiC–Ni based cermets on substrate steel by thermal explosion under load-tribological behaviour

    Directory of Open Access Journals (Sweden)

    Lemboub Samia

    2013-11-01

    Full Text Available Dans ce travail, nous nous intéressons à l'élaboration de cermets à base de TiC-Ni par dispersion de particules de carbures, oxydes ou borures dans une matrice de nickel, grâce à la technique de l'explosion thermique sous une charge de 20 MPa. La combustion de mélanges actifs (Ti-C-Ni-An où An = Al2O3, MgO, SiC, TiB2, WC, basée sur la réaction de synthèse de TiC (ΔHf298K = −184 kJ/mole, génère des cermets complexes. Un court maintien sous charge du cermet à 1373 K, après l'explosion thermique, permet son soudage sur un substrat en acier XC55. Les cermets obtenus dans ces conditions demeurent poreux et conservent une porosité de l'ordre de 25–35 %. La densité relative du cermet, sa dureté et son comportement tribologique, dépendront de la nature de l'addition dans les mélanges de départ. Porous TiC-Ni based cermets were obtained by dispersion of carbides, oxides or borides particles in a nickel matrix thanks to the thermal explosion technique realized under a load of 20 MPa. The combustion of active mixtures (Ti-C-Ni-An where An = Al2O3, MgO, SiC, TiB2 or WC based on the titanium carbide reaction synthesis (ΔHf = −184 kJ/mol, generates porous complex cermets. After the thermal explosion, a short maintenance under load at 1373 K of the combustion product, allows at the same time the cermets welding on a carbon steel substrate. The obtained cermets under these conditions preserve a porosity of about 25–35%. The relative density, hardness and tribological behaviour of the complex cermets depend on the additions nature (An in the starting mixtures.

  14. Low Temperature Rheological Behavior of Umbarka Waxy Crude and Influence of Flow Improver Etude du comportement rhéologique du brut paraffinique d'Umbarka à basse température et de l'influence d'un additif pour l'amélioration des caractéristiques d'écoulement

    Directory of Open Access Journals (Sweden)

    El-Gamal I. M.

    2006-12-01

    Full Text Available The low temperature flow properties; pour point and rheological parameters; have been determined for untreated and additive treated Umbarka waxy crude. The rheological characteristics of the crude showed non-Newtonian yield pseudoplastic flow behavior and pronounced thixotropic effect. Viscometric data are fitted to Bingham, Casson and Herschel-Bulkley plastic flow models using linear and non-linear computer regression analysis. Herschel parameters showed inconsistent results whereas Casson equation fitted the data reasonably well. Treatment of the crude with flow improver ameliorated both rheological properties and pour point but in a different manner. The influence of the additive on the rheology of the crude is greatly affected by shear rate. The thixotropic phenomenon of the crude is likely to be temperature-dependent in addition to the other controlling factors. L'objet de cette étude est de déterminer les caractéristiques du brut paraffinique d'Umbarka, avec et sans additif pour l'amélioration de l'écoulement, à savoir, l'écoulement à basse température, le point d'écoulement, et les données rhéologiques. Les caractéristiques rhéologiques du brut font apparaître un comportement d'écoulement pseudoplastique avec une limite élastique non newtonienne ainsi qu'un effet thixotropique accusé. Une corrélation a été établie entre les données viscométriques et les modèles d'écoulement plastique de Bingham, Casson et Herschel-Bulkley en utilisant une analyse de régression informatique linéaire et non linéaire. Si les paramètres de Herschel conduisent à des résultats incohérents, l'équation de Casson, en revanche, permet d'établir une corrélation raisonnablement satisfaisante des données. Le traitement du brut à l'aide d'un additif d'amélioration de l'écoulement a des répercussions positives, quoique différentes, sur les propriétés rhéologiques et le point d'écoulement. Les effets de l'additif sur la rh

  15. Altered structural connectome in temporal lobe epilepsy.

    Science.gov (United States)

    DeSalvo, Matthew N; Douw, Linda; Tanaka, Naoaki; Reinsberger, Claus; Stufflebeam, Steven M

    2014-03-01

    To study differences in the whole-brain structural connectomes of patients with left temporal lobe epilepsy (TLE) and healthy control subjects. This study was approved by the institutional review board, and all individuals gave signed informed consent. Sixty-direction diffusion-tensor imaging and magnetization-prepared rapid acquisition gradient-echo (MP-RAGE) magnetic resonance imaging volumes were analyzed in 24 patients with left TLE and in 24 healthy control subjects. MP-RAGE volumes were segmented into 1015 regions of interest (ROIs) spanning the entire brain. Deterministic white matter tractography was performed after voxelwise tensor calculation. Weighted structural connectivity matrices were generated by using the pairwise density of connecting fibers between ROIs. Graph theoretical measures of connectivity networks were compared between groups by using linear models with permutation testing. Patients with TLE had 22%-45% reduced (P < .01) distant connectivity in the medial orbitofrontal cortex, temporal cortex, posterior cingulate cortex, and precuneus, compared with that in healthy subjects. However, local connectivity, as measured by means of network efficiency, was increased by 85%-270% (P < .01) in the medial and lateral frontal cortices, insular cortex, posterior cingulate cortex, precuneus, and occipital cortex in patients with TLE as compared with healthy subjects. This study suggests that TLE involves altered structural connectivity in a network that reaches beyond the temporal lobe, especially in the default mode network.

  16. Perinatal TCDD exposure alters developmental neuroendocrine system.

    Science.gov (United States)

    Ahmed, R G

    2011-06-01

    This study tested whether maternal exposure to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) may disrupt the development of neuroendocrine system of their offspring during the perinatal period. TCDD (0.2 or 0.4 μg/kg body weight) was orally administered to pregnant rats from gestation day (GD) 1 to lactation day (LD) 30. Potential effects on neuroendocrine function were evaluated by measuring serum thyroid hormone levels in pregnant rats and their offspring and measuring some biochemical parameters in cerebellum of these offspring on GD 16 and 19, and LD 10, 20, and 30. In both treated groups, a decrease in serum thyroxine (T4), triiodothyronine (T3) and increase in thyrotropin (TSH) levels were noticed during the tested days in dams and offspring, as well as GH levels were decreased in offspring with respect to control group. In cerebellum of control offspring, the levels of monoamines, γ-aminobutyric acid (GABA) and acetylcholinesterase (AchE) were found to be increased from GD 16 to LD 30. The hypothyroid conditions due to both maternal administrations of TCDD produced inhibitory effects on monoamines and AchE, and stimulatory actions on GABA in cerebellum of offspring. These alterations were dose and age dependent. Overall, these results suggest that TCDD may act as neuroendocrine disruptor. Crown Copyright © 2011. Published by Elsevier Ltd. All rights reserved.

  17. Cerebral blood volume alterations during fractional pneumoencephalography

    International Nuclear Information System (INIS)

    Voigt, K.; Greitz, T.

    1976-01-01

    Simultaneous and continuous measurements of the cerebral blood volume (CBV), cerebrospinal fluid (CSF) and blood pressure were carried out in six patients during fractional pneumoencephalography in order to examine intracranial volumetric interactions. Three patients (Group A) showed normal encephalographic findings, and in three patients (Group B) communicating hydrocephalus with convexity block was found encephalographically. In all patients the injection of air was followed by an immediate increase of CSF pressure and blood pressure and a concomitant decrease of CBV. The initial CSF pressure was invariably re-established within 3 to 3.5 min. During this time interval the CBV of the patients of Group B decreased significantly and 30 percent more than that of Group A. Furthermore, after restoration of the original CSF pressure, CBV returned to its initial level in all patients of Group A, whereas it remained unchanged or showed a further decrease in the patients of Group B. Removal of an amount of CSF corresponding to half of the amount of injected air was followed by a significant reactive hyperemic response in two normal patients. The intracranial volumetric alterations during fractional pneumoencephalography are discussed in detail with respect to the underlying physiologic mechanisms and are suggested as a model for acute and low pressure hydrocephalus

  18. Altered default network activity in obesity.

    Science.gov (United States)

    Tregellas, Jason R; Wylie, Korey P; Rojas, Donald C; Tanabe, Jody; Martin, Jesse; Kronberg, Eugene; Cordes, Dietmar; Cornier, Marc-Andre

    2011-12-01

    The regulation of energy intake is a complex process involving the integration of homeostatic signals and both internal and external sensory inputs. To better understand the neurobiology of this process and how it may be dysfunctional in obesity, this study examined activity of the brain's "default network" in reduced-obese (RO) as compared to lean individuals. The default network is a group of functionally connected brain regions thought to play an important role in internally directed cognitive activity and the interplay between external and internal sensory processing. Functional magnetic resonance imaging was performed in 24 lean and 18 RO individuals in the fasted state after 2 days of eucaloric energy intake and after 2 days of 30% overfeeding in a counterbalanced design. Scanning was performed while subjects passively viewed images of food and nonfood objects. Independent component analysis was used to identify the default network component. In the eucaloric state, greater default network activity was observed in RO compared to lean individuals in the lateral inferior parietal and posterior cingulate cortices. Activity was positively correlated with appetite. Overfeeding resulted in increased default network activity in lean but not RO individuals. These findings suggest that the function of the default network, a major contributor to intrinsic neuronal activity, is altered in obesity and/or obese-prone individuals. Future studies of the network's function and its relationship to other brain networks may improve our understanding of the mechanisms and treatment of obesity.

  19. Can bread processing conditions alter glycaemic response?

    Science.gov (United States)

    Lau, Evelyn; Soong, Yean Yean; Zhou, Weibiao; Henry, Jeyakumar

    2015-04-15

    Bread is a staple food that is traditionally made from wheat flour. This study aimed to compare the starch digestibility of western baked bread and oriental steamed bread. Four types of bread were prepared: western baked bread (WBB) and oriental steamed bread (OSB), modified baked bread (MBB) made with the OSB recipe and WBB processing, and modified steamed bread (MSB) made with the WBB recipe and OSB processing. MBB showed the highest starch digestibility in vitro, followed by WBB, OSB and MSB. A similar trend was observed for glycaemic response in vivo. MBB, WBB, OSB and MSB had a glycaemic index of 75±4, 71±5, 68±5 and 65±4, respectively. Processing differences had a more pronounced effect on starch digestibility in bread, and steamed bread was healthier in terms of glycaemic response. The manipulation of processing conditions could be an innovative route to alter the glycaemic response of carbohydrate-rich foods. Copyright © 2014 Elsevier Ltd. All rights reserved.

  20. Stabilization of LCD devices via geometric alteration.

    Science.gov (United States)

    Jeon, Il; Yoon, MinSung; Lee, Je-Hoon

    2013-02-20

    Glass bending in LCD displays is an inherent problem that has challenged many engineers. As a solution to this problem, we propose a methodology that can tackle the root of the phenomenon in terms of linear elastic beam theory. Using this hypothesis, we devised a background theory and a solution. In this paper, we present a glass panel to which geometrical changes, such as furrow, groove, and curb have been applied. These geometrical changes are applied to the nonactive area of the glass panel. To confirm the validity of our approach, we conducted simulation tests as well as hands-on experiments to observe the thermo-mechanical behavior of the device under various conditions. The simulation results using the Ansys simulator show that the proposed technique can reduce the deformation level of panel bending by 40%. In the experiment using a bare cell with polarizer films attached and with performing the high temperature reliability test, the deformation level of panel bending is reduced by half compared to the reference glass panel without any geometric alteration.

  1. Taurine depletion alters vascular reactivity in rats.

    Science.gov (United States)

    Abebe, Worku; Mozaffari, Mahmood S

    2003-09-01

    We recently showed that chronic taurine supplementation is associated with attenuation of contractile responses of rat aorta to norepinephrine and potassium chloride. However, the potential involvement of endogenous taurine in modulation of vascular reactivity is not known. Therefore, we examined the effect of beta-alanine-induced taurine depletion on the in vitro reactivity of rat aorta to selected vasoactive agents. The data indicate that both norepinephrine- and potassium-chloride-induced maximum contractile responses of endothelium-denuded aortae were enhanced in taurine-depleted rats compared with control animals. However, taurine depletion did not affect tissue sensitivity to either norepinephrine or potassium chloride. By contrast, sensitivity of the endothelium-denuded aortae to sodium nitroprusside was attenuated by taurine depletion. Similarly, taurine deficiency reduced the relaxant responses of endothelium-intact aortic rings elicited by submaximal concentrations of acetylcholine, and this effect was associated with decreased nitric oxide production. Taken together, the data suggest that taurine depletion augments contractility but attenuates relaxation of vascular smooth muscle in a nonspecific manner. Impairment of endothelium-dependent responses, which is at least in part associated with reduced nitric oxide generation, may contribute to the attenuation of the vasorelaxant responses. These vascular alterations could be of potential consequence in pathological conditions associated with taurine deficiency.

  2. Paternal Age Alters Social Development in Offspring.

    Science.gov (United States)

    Janecka, Magdalena; Haworth, Claire M A; Ronald, Angelica; Krapohl, Eva; Happé, Francesca; Mill, Jonathan; Schalkwyk, Leonard C; Fernandes, Cathy; Reichenberg, Abraham; Rijsdijk, Frühling

    2017-05-01

    Advanced paternal age (APA) at conception has been linked with autism and schizophrenia in offspring, neurodevelopmental disorders that affect social functioning. The current study explored the effects of paternal age on social development in the general population. We used multilevel growth modeling to investigate APA effects on socioemotional development from early childhood until adolescence, as measured by the Strengths and Difficulties Questionnaire (SDQ) in the Twins Early Development Study (TEDS) sample. We also investigated genetic and environmental underpinnings of the paternal age effects on development, using the Additive genetics, Common environment, unique Environment (ACE) and gene-environment (GxE) models. In the general population, both very young and advanced paternal ages were associated with altered trajectory of social development (intercept: p = .01; slope: p = .03). No other behavioral domain was affected by either young or advanced age at fatherhood, suggesting specificity of paternal age effects. Increased importance of genetic factors in social development was recorded in the offspring of older but not very young fathers, suggesting distinct underpinnings of the paternal age effects at these two extremes. Our findings highlight that the APA-related deficits that lead to autism and schizophrenia are likely continuously distributed in the population. Copyright © 2017 American Academy of Child and Adolescent Psychiatry. Published by Elsevier Inc. All rights reserved.

  3. Percent tissue altered and corneal ectasia.

    Science.gov (United States)

    Santhiago, Marcony R

    2016-07-01

    This article reviews the association of a novel metric, percentage tissue altered (PTA), with the occurrence of ectasia after laser in-situ keratomileusis in eyes with normal corneal topography, and analyses the influence of the variables that comprise it, and its role on eyes with suspicious topography. PTA is derived from [PTA = (FT + AD)/CCT] where FT = flap thickness, AD = ablation depth, and CCT = preoperative central corneal thickness. Our studies revealed that there is a robust relationship between high PTA and ectasia risk in eyes with normal preoperative topography. PTA higher or equal to 40% presented the highest odds ratio and highest predictive capabilities for ectasia risk than each of the variables that comprise it, residual stromal bed or age. Average thicker flaps alone were insufficient to create ectasia unless coupled with greater ablation depths, meaning a high PTA. In eyes with suspicious topography, even low PTA value is sufficient to induce ectasia. This new metric, PTA, should be taken into account when screening patients for refractive surgery. Patients with normal topography or tomography, presenting a PTA higher or equal to 40% should be considered at higher risk for post laser in-situ keratomileusis ectasia.

  4. Genetic alterations during radiation-induced carcinogenesis

    International Nuclear Information System (INIS)

    Kodama, Seiji

    1995-01-01

    This paper reviews radiation-induced genetic alterations and its carcinogenesis, focusing on the previous in vitro assay outcome. A colony formation assay using Syrian hamster fetal cells and focus formation assay using mouse C3H10T1/2 cells are currently available to find malignant transformation of cells. Such in vitro assays has proposed the hypothesis that radiation-induced carcinogenesis arises from at least two-stage processes; i.e., that an early step induced by irradiation plays an important role in promoting the potential to cause the subsequent mutation. A type of genetic instability induced by radiation results in a persistently elevated frequency of spontaneous mutations, so-called the phenomenon of delayed reproductive death. One possible mechanism by which genetic instability arises has been shown to be due to the development of abnormality in the gene group involved in the maintenance mechanism of genome stability. Another possibility has also been shown to stem from the loss of telomere (the extremities of a chromosome). The importance of search for radiation-induced genetic instability is emphasized in view of the elucidation of carcinogenesis. (N.K.)

  5. Plant growth conditions alter phytolith carbon

    Directory of Open Access Journals (Sweden)

    Kimberley L Gallagher

    2015-09-01

    Full Text Available Many plants, including grasses and some important human food sources, accumulate and precipitate silica in their cells to form opaline phytoliths. These phytoliths contain small amounts of organic matter (OM that are trapped during the process of silicification. Previous work has suggested that plant silica is associated with compounds such as proteins, lipids, lignin and carbohydrate complexes. It is not known whether these compounds are cellular components passively encapsulated as the cell silicifies, polymers actively involved in the precipitation process or random compounds assimilated by the plant and discarded into a glass wastebasket. Here, we used Raman spectroscopy to map the distribution of OM in phytoliths, and to analyze individual phytoliths isolated from Sorghum bicolor plants grown under different laboratory treatments. Using mapping, we showed that OM in phytoliths is distributed throughout the silica and is not related to dark spots visible in light microscopy, previously assumed to be the repository for phytolith OM. The Raman spectra exhibited common bands indicative of C-H stretching modes of general OM, and further more diagnostic bands consistent with carbohydrates, lignins and other OM. These Raman spectra exhibited variability of spectral signatures and of relative intensities between sample treatments indicating that differing growth conditions altered the phytolith carbon. This may have strong implications for understanding the mechanism of phytolith formation, and for use of phytolith carbon isotope values in dating or paleoclimate reconstruction.

  6. Shadows alter facial expressions of Noh masks.

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    Nobuyuki Kawai

    Full Text Available BACKGROUND: A Noh mask, worn by expert actors during performance on the Japanese traditional Noh drama, conveys various emotional expressions despite its fixed physical properties. How does the mask change its expressions? Shadows change subtly during the actual Noh drama, which plays a key role in creating elusive artistic enchantment. We here describe evidence from two experiments regarding how attached shadows of the Noh masks influence the observers' recognition of the emotional expressions. METHODOLOGY/PRINCIPAL FINDINGS: In Experiment 1, neutral-faced Noh masks having the attached shadows of the happy/sad masks were recognized as bearing happy/sad expressions, respectively. This was true for all four types of masks each of which represented a character differing in sex and age, even though the original characteristics of the masks also greatly influenced the evaluation of emotions. Experiment 2 further revealed that frontal Noh mask images having shadows of upward/downward tilted masks were evaluated as sad/happy, respectively. This was consistent with outcomes from preceding studies using actually tilted Noh mask images. CONCLUSIONS/SIGNIFICANCE: Results from the two experiments concur that purely manipulating attached shadows of the different types of Noh masks significantly alters the emotion recognition. These findings go in line with the mysterious facial expressions observed in Western paintings, such as the elusive qualities of Mona Lisa's smile. They also agree with the aesthetic principle of Japanese traditional art "yugen (profound grace and subtlety", which highly appreciates subtle emotional expressions in the darkness.

  7. Triclosan alterations of estuarine phytoplankton community structure.

    Science.gov (United States)

    Pinckney, James L; Thompson, Laura; Hylton, Sarah

    2017-06-15

    Antimicrobial additives in pharmaceutical and personal care products are a major environmental concern due to their potential ecological impacts on aquatic ecosystems. Triclosan (TCS) has been used as an antiseptic, disinfectant, and preservative in various media. The sublethal and lethal effects of TCS on estuarine phytoplankton community composition were investigated using bioassays of natural phytoplankton communities to measure phytoplankton responses to different concentrations of TCS ranging from 1 to 200μgl -1 . The EC 50 (the concentration of an inhibitor where the growth is reduced by half) for phytoplankton groups (diatoms, chlorophytes, cryptophytes) examined in this ranged from 10.7 to 113.8μg TCS l -1 . Exposures resulted in major shifts in phytoplankton community composition at concentrations as low as 1.0μg TCS l -1 . This study demonstrates estuarine ecosystem sensitivity to TCS exposure and highlights potential alterations in phytoplankton community composition at what are typically environmental concentrations of TCS in urbanized estuaries. Copyright © 2017 Elsevier Ltd. All rights reserved.

  8. Radiofrequency treatment alters cancer cell phenotype

    Science.gov (United States)

    Ware, Matthew J.; Tinger, Sophia; Colbert, Kevin L.; Corr, Stuart J.; Rees, Paul; Koshkina, Nadezhda; Curley, Steven; Summers, H. D.; Godin, Biana

    2015-07-01

    The importance of evaluating physical cues in cancer research is gradually being realized. Assessment of cancer cell physical appearance, or phenotype, may provide information on changes in cellular behavior, including migratory or communicative changes. These characteristics are intrinsically different between malignant and non-malignant cells and change in response to therapy or in the progression of the disease. Here, we report that pancreatic cancer cell phenotype was altered in response to a physical method for cancer therapy, a non-invasive radiofrequency (RF) treatment, which is currently being developed for human trials. We provide a battery of tests to explore these phenotype characteristics. Our data show that cell topography, morphology, motility, adhesion and division change as a result of the treatment. These may have consequences for tissue architecture, for diffusion of anti-cancer therapeutics and cancer cell susceptibility within the tumor. Clear phenotypical differences were observed between cancerous and normal cells in both their untreated states and in their response to RF therapy. We also report, for the first time, a transfer of microsized particles through tunneling nanotubes, which were produced by cancer cells in response to RF therapy. Additionally, we provide evidence that various sub-populations of cancer cells heterogeneously respond to RF treatment.

  9. Pulmonary biochemical alterations resulting from ozone exposure

    Energy Technology Data Exchange (ETDEWEB)

    Mustafa, M.G.; Lee, S.D.

    1976-07-01

    Metabolic response of lung tissue to ozone was studied in rats and monkeys after exposure of animals to various levels of ozone (0.1 to 0.8 ppM) for 1 to 30 days. In rats, 0.8 ppM ozone exposure resulted in a 40 to 50 percent augmentation of oxygen utilization in lung homogenate in the presence of an added substrate (e.g., succinate or 2-oxoglutarate). Activities of marker enzymes, viz. mitochondrial succinate-cytochrome c reductase; microsomal NADPH-cytochrome c reductase and cytosolic glucose-6-phosphate dehydrogenase, increased maximally (40 to 70 percent over control) after 3 to 4 days of exposure, and remained elevated throughout the 0.8 ppM ozone exposure for 30 days. In monkeys, the observations were the same except that the magnitude of biochemical changes was relatively smaller. Exposure of animals to lower levels of ozone resulted in proportionately smaller biochemical changes in the lung, and ozone effects were detectable up to the 0.2 ppM level. While 0.1 ppM ozone exposure was ineffective, dietary deficiency of vitamin E, a natural antioxidant, increased the sensitivity of rat lungs to this concentration of ozone. The results suggest that low-level ozone exposures may cause metabolic alterations in the lung, and that dietary supplementation of vitamin E may offer protection against oxidant stress.

  10. Alterated integrin expression in lichen planopilaris

    Directory of Open Access Journals (Sweden)

    Erriquez Roberta

    2007-02-01

    Full Text Available Abstract Background Lichen planopilaris (LPP is an inflammatory disease characterized by a lymphomononuclear infiltrate surrounding the isthmus and infundibulum of the hair follicle of the scalp, that evolves into atrophic/scarring alopecia. In the active phase of the disease hairs are easily plucked with anagen-like hair-roots. In this study we focused on the expression of integrins and basement membrane components of the hair follicle in active LPP lesions. Methods Scalp biopsies were taken in 10 patients with LPP and in 5 normal controls. Using monoclonal antibodies against α3β1 and α6β4 integrins we showed the expression of these integrins and of the basement membrane components of the hair follicle in active LPP lesions and in healthy scalp skin. Results In the LPP involved areas, α3β1 was distributed in a pericellular pattern, the α6 subunit was present with a basolateral distribution while the β4 subunit showed discontinuous expression at the basal pole and occasionally, basolateral staining of the hair follicle. Conclusion: An altered distribution of the integrins in active LPP lesions can explain the phenomenon of easy pulling-out of the hair with a "gelatinous" root-sheath.

  11. Alters in dissociative identity disorder. Metaphors or genuine entities?

    Science.gov (United States)

    Merckelbach, Harald; Devilly, Grant J; Rassin, Eric

    2002-05-01

    How should the different identities (i.e., alters) that are thought to be typical for dissociative identity disorder (DID) be interpreted? Are they just metaphors for different emotional states or are they truly autonomous entities that are capable of willful action? This issue is important because it has implications for the way in which courts may handle cases that involve DID patients. Referring to studies demonstrating that alters of DID patients differ in their memory performance or physiological profile, some authors have concluded that alters are more than just metaphors. We argue that such line of reasoning is highly problematic. There is little consensus among authors about the degree to which various types of memory information (implicit, explicit, procedural) may leak from one to the other alter. Without such theoretical accord, any given outcome of memory studies on DID may be taken as support for the assumption that alters are in some sense "real." As physiological studies on alter activity often lack proper control conditions, most of them are inconclusive as to the status of alters. To date, neither memory studies nor psychobiological studies have delivered compelling evidence that alters of DID patients exist in a factual sense. As a matter of fact, results of these studies are open to multiple interpretations and in no way refute an interpretation of alters in terms of metaphors for different emotional states.

  12. Optical tweezers reveal how proteins alter replication

    Science.gov (United States)

    Chaurasiya, Kathy

    Single molecule force spectroscopy is a powerful method that explores the DNA interaction properties of proteins involved in a wide range of fundamental biological processes such as DNA replication, transcription, and repair. We use optical tweezers to capture and stretch a single DNA molecule in the presence of proteins that bind DNA and alter its mechanical properties. We quantitatively characterize the DNA binding mechanisms of proteins in order to provide a detailed understanding of their function. In this work, we focus on proteins involved in replication of Escherichia coli (E. coli ), endogenous eukaryotic retrotransposons Ty3 and LINE-1, and human immunodeficiency virus (HIV). DNA polymerases replicate the entire genome of the cell, and bind both double-stranded DNA (dsDNA) and single-stranded DNA (ssDNA) during DNA replication. The replicative DNA polymerase in the widely-studied model system E. coli is the DNA polymerase III subunit alpha (DNA pol III alpha). We use optical tweezers to determine that UmuD, a protein that regulates bacterial mutagenesis through its interactions with DNA polymerases, specifically disrupts alpha binding to ssDNA. This suggests that UmuD removes alpha from its ssDNA template to allow DNA repair proteins access to the damaged DNA, and to facilitate exchange of the replicative polymerase for an error-prone translesion synthesis (TLS) polymerase that inserts nucleotides opposite the lesions, so that bacterial DNA replication may proceed. This work demonstrates a biophysical mechanism by which E. coli cells tolerate DNA damage. Retroviruses and retrotransposons reproduce by copying their RNA genome into the nuclear DNA of their eukaryotic hosts. Retroelements encode proteins called nucleic acid chaperones, which rearrange nucleic acid secondary structure and are therefore required for successful replication. The chaperone activity of these proteins requires strong binding affinity for both single- and double-stranded nucleic

  13. Deforestation alters rainfall: a myth or reality

    Science.gov (United States)

    Hanif, M. F.; Mustafa, M. R.; Hashim, A. M.; Yusof, K. W.

    2016-06-01

    To cope with the issue of food safety and human shelter, natural landscape has gone through a number of alterations. In the coming future, the expansion of urban land and agricultural farms will likely disrupt the natural environment. Researchers have claimed that land use change may become the most serious issue of the current century. Thus, it is necessary to understand the consequences of land use change on the climatic variables, e.g., rainfall. This study investigated the impact of deforestation on local rainfall. An integrated methodology was adopted to achieve the objectives. Above ground biomass was considered as the indicator of forest areas. Time series data of a Moderate Resolution Imaging Spectroradiometer (MODIS) sensor were obtained for the year of 2000, 2005, and 2010. Rainfall data were collected from the Department of Irrigation and Drainage, Malaysia. The MODIS time series data were classified and four major classes were developed based on the Normalised Difference Vegetation Index (NDVI) ranges. The results of the classification showed that water, and urban and agricultural lands have increased in their area by 2, 3, and 6%, respectively. On the other hand, the area of forest has decreased 10% collectively from 2000 to 2010. The results of NDVI and rainfall data were analysed by using a linear regression analysis. The results showed a significant relationship at a 90% confidence interval between rainfall and deforestation (t = 1.92, p = 0.06). The results of this study may provide information about the consequences of land use on the climate on the local scale.

  14. Algal toxins alter copepod feeding behavior.

    Directory of Open Access Journals (Sweden)

    Jiarong Hong

    Full Text Available Using digital holographic cinematography, we quantify and compare the feeding behavior of free-swimming copepods, Acartia tonsa, on nutritional prey (Storeatula major to that occurring during exposure to toxic and non-toxic strains of Karenia brevis and Karlodinium veneficum. These two harmful algal species produce polyketide toxins with different modes of action and potency. We distinguish between two different beating modes of the copepod's feeding appendages-a "sampling beating" that has short durations (<100 ms and involves little fluid entrainment and a longer duration "grazing beating" that persists up to 1200 ms and generates feeding currents. The durations of both beating modes have log-normal distributions. Without prey, A. tonsa only samples the environment at low frequency. Upon introduction of non-toxic food, it increases its sampling time moderately and the grazing period substantially. On mono algal diets for either of the toxic dinoflagellates, sampling time fraction is high but the grazing is very limited. A. tonsa demonstrates aversion to both toxic algal species. In mixtures of S. major and the neurotoxin producing K. brevis, sampling and grazing diminish rapidly, presumably due to neurological effects of consuming brevetoxins while trying to feed on S. major. In contrast, on mixtures of cytotoxin producing K. veneficum, both behavioral modes persist, indicating that intake of karlotoxins does not immediately inhibit the copepod's grazing behavior. These findings add critical insight into how these algal toxins may influence the copepod's feeding behavior, and suggest how some harmful algal species may alter top-down control exerted by grazers like copepods.

  15. Metabolic alterations in experimental models of depression

    Directory of Open Access Journals (Sweden)

    Maria G. Puiu

    2016-10-01

    Full Text Available Introduction: Major depressive disorder is one of the most prevalent psychiatric disorders and is associated with a severe impact on the personal functioning, thus with incurring significant direct and indirect costs. The presence of depression in patients with medical comorbidities increases the risks of myocardial infarction and decreases diabetes control, and adherence to treatment. The mechanism through which these effects are produced is still uncertain. Objectives of this study were to evaluate the metabolic alterations in female Wistar rats with induced depression, with and without administration of Agomelatine. The methods included two experiments. All data were analyzed by comparison with group I (control, and with each other. In the first experiment we induced depression by: exposure to chronic mild stress-group II; olfactory bulbectomy-group III; and exposure to chronic mild stress and hyperlipidic/ hyper caloric dietgroup IV. The second experiment was similar with the first but the rats received Agomelatine (0.16mg/ animal: group V (depression induced through exposure to chronic mild stress, VI (depression induced through olfactory bulbectomy and VII (depression induced through exposure to chronic mild stressing hyperlipidic/ hypercaloric diet. Weight, cholesterol, triglycerides and glycaemia were measured at day 0 and 28, and leptin value was measured at day 28. The results in the 1st experiment revealed significant differences (p<0.01 for weight and cholesterol in Group IV, for triglycerides in groups III and IV (p<0.001, and for glycaemia in group II. The 2nd experiment revealed significant differences (p<0.001 in group VII for weight and triglycerides, and in groups V and VI for triglycerides (p<0.01. In conclusion, significant correlations were found between high level of triglycerides and depression induced by chronic stress and olfactory bulbectomy. Agomelatine groups had a lower increase of triglycerides levels.

  16. Management intensity alters decomposition via biological pathways

    Science.gov (United States)

    Wickings, Kyle; Grandy, A. Stuart; Reed, Sasha; Cleveland, Cory

    2011-01-01

    Current conceptual models predict that changes in plant litter chemistry during decomposition are primarily regulated by both initial litter chemistry and the stage-or extent-of mass loss. Far less is known about how variations in decomposer community structure (e.g., resulting from different ecosystem management types) could influence litter chemistry during decomposition. Given the recent agricultural intensification occurring globally and the importance of litter chemistry in regulating soil organic matter storage, our objectives were to determine the potential effects of agricultural management on plant litter chemistry and decomposition rates, and to investigate possible links between ecosystem management, litter chemistry and decomposition, and decomposer community composition and activity. We measured decomposition rates, changes in litter chemistry, extracellular enzyme activity, microarthropod communities, and bacterial versus fungal relative abundance in replicated conventional-till, no-till, and old field agricultural sites for both corn and grass litter. After one growing season, litter decomposition under conventional-till was 20% greater than in old field communities. However, decomposition rates in no-till were not significantly different from those in old field or conventional-till sites. After decomposition, grass residue in both conventional- and no-till systems was enriched in total polysaccharides relative to initial litter, while grass litter decomposed in old fields was enriched in nitrogen-bearing compounds and lipids. These differences corresponded with differences in decomposer communities, which also exhibited strong responses to both litter and management type. Overall, our results indicate that agricultural intensification can increase litter decomposition rates, alter decomposer communities, and influence litter chemistry in ways that could have important and long-term effects on soil organic matter dynamics. We suggest that future

  17. Alterations of the Gut Microbiome in Hypertension

    Directory of Open Access Journals (Sweden)

    Qiulong Yan

    2017-08-01

    Full Text Available Introduction: Human gut microbiota is believed to be directly or indirectly involved in cardiovascular diseases and hypertension. However, the identification and functional status of the hypertension-related gut microbe(s have not yet been surveyed in a comprehensive manner.Methods: Here we characterized the gut microbiome in hypertension status by comparing fecal samples of 60 patients with primary hypertension and 60 gender-, age-, and body weight-matched healthy controls based on whole-metagenome shotgun sequencing.Results: Hypertension implicated a remarkable gut dysbiosis with significant reduction in within-sample diversity and shift in microbial composition. Metagenome-wide association study (MGWAS revealed 53,953 microbial genes that differ in distribution between the patients and healthy controls (false discovery rate, 0.05 and can be grouped into 68 clusters representing bacterial species. Opportunistic pathogenic taxa, such as, Klebsiella spp., Streptococcus spp., and Parabacteroides merdae were frequently distributed in hypertensive gut microbiome, whereas the short-chain fatty acid producer, such as, Roseburia spp. and Faecalibacterium prausnitzii, were higher in controls. The number of hypertension-associated species also showed stronger correlation to the severity of disease. Functionally, the hypertensive gut microbiome exhibited higher membrane transport, lipopolysaccharide biosynthesis and steroid degradation, while in controls the metabolism of amino acid, cofactors and vitamins was found to be higher. We further provided the microbial markers for disease discrimination and achieved an area under the receiver operator characteristic curve (AUC of 0.78, demonstrating the potential of gut microbiota in prediction of hypertension.Conclusion: These findings represent specific alterations in microbial diversity, genes, species and functions of the hypertensive gut microbiome. Further studies on the causality relationship between

  18. Altered thalamic functional connectivity in multiple sclerosis

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Yaou; Liang, Peipeng; Duan, Yunyun; Huang, Jing; Ren, Zhuoqiong; Jia, Xiuqin [Department of Radiology, Xuanwu Hospital, Capital Medical University, Beijing 100053 (China); Dong, Huiqing; Ye, Jing [Department of Neurology, Xuanwu Hospital, Capital Medical University, Beijing 100053 (China); Shi, Fu-Dong [Department of Neurology and Tianjin Neurological Institute, Tianjin Medical University General Hospital, Tianjin 300052 (China); Butzkueven, Helmut [Department of Medicine, University of Melbourne, Parkville 3010 (Australia); Li, Kuncheng, E-mail: kunchengli55@gmail.com [Department of Radiology, Xuanwu Hospital, Capital Medical University, Beijing 100053 (China)

    2015-04-15

    Highlights: •We demonstrated decreased connectivity between thalamus and cortical regions in MS. •Increased intra- and inter-thalamic connectivity was also observed in MS. •The increased functional connectivity is attenuated by increasing disease duration. -- Abstract: Objective: To compare thalamic functional connectivity (FC) in patients with multiple sclerosis (MS) and healthy controls (HC), and correlate these connectivity measures with other MRI and clinical variables. Methods: We employed resting-state functional MRI (fMRI) to examine changes in thalamic connectivity by comparing thirty-five patients with MS and 35 age- and sex-matched HC. Thalamic FC was investigated by correlating low frequency fMRI signal fluctuations in thalamic voxels with voxels in all other brain regions. Additionally thalamic volume fraction (TF), T2 lesion volume (T2LV), EDSS and disease duration were recorded and correlated with the FC changes. Results: MS patients were found to have a significantly lower TF than HC in bilateral thalami. Compared to HC, the MS group showed significantly decreased FC between thalamus and several brain regions including right middle frontal and parahippocampal gyri, and the left inferior parietal lobule. Increased intra- and inter-thalamic FC was observed in the MS group compared to HC. These FC alterations were not correlated with T2LV, thalamic volume or lesions. In the MS group, however, there was a negative correlation between disease duration and inter-thalamic connectivity (r = −0.59, p < 0.001). Conclusion: We demonstrated decreased FC between thalamus and several cortical regions, while increased intra- and inter-thalamic connectivity in MS patients. These complex functional changes reflect impairments and/or adaptations that are independent of T2LV, thalamic volume or presence of thalamic lesions. The negative correlation between disease duration and inter-thalamic connectivity could indicate an adaptive role of thalamus that is

  19. Acoustic experience alters the aged auditory system.

    Science.gov (United States)

    Turner, Jeremy G; Parrish, Jennifer L; Zuiderveld, Loren; Darr, Stacy; Hughes, Larry F; Caspary, Donald M; Idrezbegovic, Esma; Canlon, Barbara

    2013-01-01

    Presbyacusis, one of the most common ailments of the elderly, is often treated with hearing aids, which serve to reintroduce some or all of those sounds lost to peripheral hearing loss. However, little is known about the underlying changes to the ear and brain as a result of such experience with sound late in life. The present study attempts to model this process by rearing aged CBA mice in an augmented acoustic environment (AAE). Aged (22-23 months) male (n = 12) and female (n = 9) CBA/CaJ mice were reared in either 6 weeks of low-level (70 dB SPL) broadband noise stimulation (AAE) or normal vivarium conditions. Changes as a function of the treatment were measured for behavior, auditory brainstem response thresholds, hair cell cochleograms, and gamma aminobutyric acid neurochemistry in the key central auditory structures of the inferior colliculus and primary auditory cortex. The AAE-exposed group was associated with sex-specific changes in cochlear pathology, auditory brainstem response thresholds, and gamma aminobutyric acid neurochemistry. Males exhibited significantly better thresholds and reduced hair cell loss (relative to controls) whereas females exhibited the opposite effect. AAE was associated with increased glutamic acid decarboxylase (GAD67) levels in the inferior colliculus of both male and female mice. However, in primary auditory cortex AAE exposure was associated with increased GAD67 labeling in females and decreased GAD67 in males. These findings suggest that exposing aged mice to a low-level AAE alters both peripheral and central properties of the auditory system and these changes partially interact with sex or the degree of hearing loss before AAE. Although direct application of these findings to hearing aid use or auditory training in aged humans would be premature, the results do begin to provide direct evidence for the underlying changes that might be occurring as a result of hearing aid use late in life. These results suggest the aged brain

  20. STRUCTURAL ALTERATIONS OF SKELETAL MUSCLE IN COPD

    Directory of Open Access Journals (Sweden)

    Sunita eMathur

    2014-03-01

    Full Text Available Background: Chronic obstructive pulmonary disease (COPD is a respiratory disease associated with a systemic inflammatory response. Peripheral muscle dysfunction has been well characterized in individuals with COPD and results from a complex interaction between systemic and local factors. Objective: In this narrative review, we will describe muscle wasting in people with COPD, the associated structural changes, muscle regenerative capacity and possible mechanisms for muscle wasting. We will also discuss how structural changes relate to impaired muscle function and mobility in people with COPD. Key Observations: Approximately 30-40% of individuals with COPD experience muscle mass depletion. Furthermore, muscle atrophy is a predictor of physical function and mortality in this population. Associated structural changes include a decreased proportion and size of type-I fibers, reduced oxidative capacity and mitochondrial density mainly in the quadriceps. Observations related to impaired muscle regenerative capacity in individuals with COPD include a lower proportion of central nuclei in the presence or absence of muscle atrophy and decreased maximal telomere length, which has been correlated with reduced muscle cross-sectional area. Potential mechanisms for muscle wasting in COPD may include excessive production of reactive oxygen species, altered amino acid metabolism and lower expression of peroxisome proliferator-activated receptors-gamma-coactivator 1-alpha mRNA. Despite a moderate relationship between muscle atrophy and function, impairments in oxidative metabolism only seems weakly related to muscle function. Conclusion: This review article demonstrates the cellular modifications in the peripheral muscle of people with COPD and describes the evidence of its relationship to muscle function. Future research will focus on rehabilitation strategies to improve muscle wasting and maximize function.

  1. Persistent Memory Effects and the Mid- and Post-Brick Dynamic Behaviour of Three-Way Automotive Catalysts Effets mémoires persistants et comportement dynamique des briques médiane et postérieure de catalyseurs automobiles à trois voies

    Directory of Open Access Journals (Sweden)

    Peyton Jones J.C.

    2011-09-01

    Full Text Available This paper presents the results of an experimental study into the dynamic behaviour of a three-way automotive catalyst and its associated exhaust gas oxygen sensors. Motivated by issues of feedback sensor location, the study seeks to overlay the results of repeat experiments, with sensors and fast-response gas analyzers positioned at different locations, in order to obtain a detailed picture of system dynamics at different points within the catalyst. Initial results demonstrated that the dynamic response of the catalyst can be significantly affected by a persistent memory effect in addition to reversible deactivation dynamics and the familiar oxygen storage/release dynamics of the system. In particular, the effects of prior rich or stoichiometric operation are shown to persist even after extended periods of lean operation. This memory effect is important, not only because of its potential impact on conversion efficiency, but also because of its impact on the repeatability of experiments carried out under what would appear to be near-identical operating conditions. By pre-conditioning under rich conditions highly repeatable experiments were achieved. The results were combined to give a detailed picture of catalyst dynamics at pre-, mid- and post-catalyst locations, and provide insight into catalyst and (non-ideal exhaust gas oxygen sensor behavior. Cet article présente les résultats d’une étude expérimentale en matière de comportement dynamique d’un catalyseur automobile à trois voies et de ses capteurs d’oxygène de gaz d’échappement associés. Motivée par les problèmes de localisation des capteurs de retour d’information, l’étude cherche à corréler les résultats d’expériences répétées, capteurs et analyseurs de gaz à réponse rapide étant disposés en des emplacements différents afin d’obtenir une image détaillée des dynamiques de système en différents points à l’intérieur du catalyseur. Les r

  2. Global changes alter soil fungal communities and alter rates of organic matter decomposition

    Science.gov (United States)

    Moore, J.; Frey, S. D.

    2016-12-01

    Global changes - such as warming, more frequent and severe droughts, increasing atmospheric CO2, and increasing nitrogen (N) deposition rates - are altering ecosystem processes. The balance between soil carbon (C) accumulation and decomposition is determined in large part by the activity and biomass of detrital organisms, namely soil fungi, and yet their sensitivity to global changes remains unresolved. We present results from a meta-analysis of 200+ studies spanning manipulative and observational field experiments to quantify fungal responses to global change and expected consequences for ecosystem C dynamics. Warming altered the functional soil microbial community by reducing the ratio of fungi to bacteria (f:b) total fungal biomass. Additionally, warming reduced lignolytic enzyme activity generally by one-third. Simulated N deposition affected f:b differently than warming, but the effect on fungal biomass and activity was similar. The effect of N-enrichment on f:b was contingent upon ecosystem type; f:b increased in alpine meadows and heathlands but decreased in temperate forests following N-enrichment. Across ecosystems, fungal biomass marginally declined by 8% in N-enriched soils. In general, N-enrichment reduced fungal lignolytic enzyme activity, which could explain why soil C accumulates in some ecosystems following warming and N-enrichment. Several global change experiments have reported the surprising result that soil C builds up following increases in temperature and N deposition rates. While site-specific studies have examined the role of soil fungi in ecosystem responses to global change, we present the first meta-analysis documenting general patterns of global change impacts on soil fungal communities, biomass, and activity. In sum, we provide evidence that soil microbial community shifts and activity plays a large part in ecosystem responses to global changes, and have the potential to alter the magnitude of the C-climate feedback.

  3. Replacing corn with sorghum in the diet alters intestinal microbiota without altering chicken performance.

    Science.gov (United States)

    Fagundes, N S; Pereira, R; Bortoluzzi, C; Rafael, J M; Napty, G S; Barbosa, J G M; Sciencia, M C M; Menten, J F M

    2017-10-01

    Sorghum grain can be used to replace corn in broiler diets. However, the effects related to an abrupt change between these grains are not yet clear. The aim of this study was to evaluate the performance and intestinal health of broilers fed diets containing corn and/or sorghum during different periods of rearing. To accomplish this aim, 2100 male chicks were fed the following experimental diets: C100% (corn-based diet); S100% (sorghum-based diet); C:S50% (diet based on corn and sorghum 1:1); PC-S (corn-based diet in the pre-starter phase and sorghum-based diet in subsequent phases); and PS-C (sorghum-based diet in the pre-starter phase and corn-based diet in subsequent phases). The study was conducted with two simultaneous trials in a randomized block design as follows: a performance trial up to 40 days occurred in floor pens (n = 8), and the metabolism trial occurred in cages (n = 10). Performance, jejunal morphometry, number of goblet cells, apparent metabolizable energy (AME), apparent metabolizable energy corrected for nitrogen (AMEn) and the coefficient of apparent metabolizability of dry matter (CMDM) of the diets, and the intestinal microbiota of small intestine and caeca at 10 and 21 days of age (16S gene sequencing) were evaluated. The different experimental diets did not affect performance, jejunal epithelium, AME, AMEn or CMDM. However, the experimental diets altered the percentages of the genera Clostridium, Weissella, Bacillus and Alkaliphilus in the small intestine. In addition, the genera Lactobacillus and Desulfotomaculum in the caeca were altered. The age also affected the microbiota of the intestinal segments. In conclusion, feeding sorghum in place of corn as well as the grain change after the pre-starter phase does not alter broiler performance. However, sorghum alters the intestinal microbiota, resulting in a lower percentage of Clostridium and a higher percentage of Lactobacillus in the small intestine and caeca, respectively. Journal of

  4. Genetic alterations and markers of melanoma

    Directory of Open Access Journals (Sweden)

    N. N. Mazurenko

    2014-01-01

    Full Text Available Melanoma remains the most deadly form of malignant skin disease with high risk of metastases. Metastatic melanoma is prognostic highly unfavorable and resistant to traditional chemotherapy and biologic treatment. There is a great progress in understanding of the molecular mechanisms underlying melanoma initiation and progression. The external (ultraviolet irradiation and internal (genetic factors are involved in melanoma genesis. 5–14 % of melanoma cases occur in familial context due to genetic predisposition risk factors. Among them rare germinal mutations in the cell cycle genes regulators CDKN2A and CDK4 and in the master gene of melanocyte homeostasis MITF, as well as single nucleotide polymorphisms of several low-penetrated genes, namely MC1R, have been identified. The main cell signaling pathways and oncogene driver mutations are involved in melanoma pathogenesis. RAS / RAF / MEK / ERK cascade is hyperactivated in 75 % of cutaneous melanoma cases. Activation of PI3K / AKT / mTOR signaling pathway is important for melanoma progression. Recent studies revealed that melanomas are genetically and phenotypically heterogeneous tumors. Spectrum of chromosomal alterations and activating mutations corresponding to tumor molecular portraits varies in melanomas of different location. Most of cutaneous melanomas contain BRAF (50 % or NRAS (20 % mutations, and NRAS mutations occur on chronically sun-exposed skin. Activating KIT mutations have been reported in approximately 20–30 % of certain subtypes of melanoma, including acral and mucosal, and melanoma that develop on photodamaged skin. Cutaneous metastatic melanoma derive from preexisting nevi in 25 % of cases, molecular mechanisms of nevi malignization are discussed. Deepsequencing approaches of melanoma samples of different melanoma types highlighted new melanoma driver genes, that are damaged due to tumorigenic effects of ultraviolet: PPP6C, RAC1, SNX31, TACC1 and STK19. The

  5. Alterations in hypothalamic function following thermal injury.

    Science.gov (United States)

    Wilmore, D W; Orcutt, T W; Mason, A D; Pruitt, B A

    1975-08-01

    Nine burn patients with a mean burn size of 39% (range, 23-65%) and five normal individuals studied in an environmental chamber selected optimal comfort temperature by regulating a bedside temperature control unit. The normal individuals selected 27.8 degrees C plus or minus 0.6 (SE) as the comfort temperature and their mean skin temperature was 33.4 plus or minus 0.6 and core temperature 36.9 plus or minus 0.1 while in this environment. In contrast, the burn patients maintained a higher ambient comfort temperature (mean 30.4 plus or minus 0.7, p less than 0.05 when compared to controls) associated with an elevated core (38.4 plus or minus 0.3, p less than 0.01) and surface temperature (35.2 plus or minus 0.4, p less than 0.05). Human growth hormone response to insulin hypoglycemia and arginine infusion was measured in nine additional burn patients (mean burn size, 52%; range, 23-90%) and five normals. Fasting HGH was significantly elevated (1.7 plus or minus 0.2 ng/ml, n = 18, versus control of 0.9 plus or minus 0.1, n = 10, p less than 0.001), despite fasting hyperglycemia in the burn patients (123 plus or minus 5 mg/100 glycemia in the burn patients (123 plus or minus 5 mg/100 ml versus 91 plus or minus 2, p less than 0.001). HGH response to insulin hypoglycemia was diminished in the burn patients with peak HGH value in patients averaging 12.6 ng/ml compared to 27.8 in the recovered patients and 32.6 in the controls (p less than 0.01). Patients receiving an arginine infusion also demonstrated diminished HGH response following injury. The HGH response to known stimuli returned toward normal with time and recovery in the surviving patients. Alterations in comfort temperature, fasting blood glucose, and glucose-HGH interaction occur following thermal trauma. These changes taken together suggest that metabolic responses to injury may be the consequence of homeostatic readjustment within the hypothalamus.

  6. Hydrothermal alteration studies of gabbros from Northern Central ...

    Indian Academy of Sciences (India)

    mation, produced strongly foliated rocks result- ing in the formation of porphyroclastic and mylonitic textures. In contrast, altered gabbro from corner high, adjacent to Vityaz TF, under- went low temperature greenschist grade alter- ation only with typical greenschist mineralogical assemblages (figure 3). The low temperature ...

  7. Mapping hydrothermal altered mineral deposits using Landsat 7 ...

    Indian Academy of Sciences (India)

    The colour composite and band ratio methods showed very clearly the hydrothermal altered deposits of clay minerals, iron oxides and ferric oxides around the fumaroles. The principal component analysis using the Crosta technique also enabled us to represent undoubtedly the altered hydroxyl and iron-oxide mineral ...

  8. Alterity: Learning Polyvalent Selves, Resisting Disabling Notions of the Self

    Science.gov (United States)

    Walker, Wayland

    2011-01-01

    This article queries how one type of human difference--alterity, the experience of multiple distinct consciousnesses, or "alters," by one person--is pathologized in American culture. This experience is inscribed as a mental illness, labeled now as dissociative identity disorder (DID) and formerly known as multiple personality disorder (MPD). In…

  9. Texture and Compositional Evidence for Epigenetic Alteration in Mn ...

    African Journals Online (AJOL)

    This communication is the first to report the presence of significant epigenetic alteration in protore manganese carbonate at the Palaeo-proterozoicNsuta manganese deposit in the Birimian of Ghana. The alteration is recognisable macroscopically by strong veining of quartz and/or pink rhodochrosite and, in some cases, ...

  10. Altered calcium metabolism: the probable major biochemical lesion ...

    African Journals Online (AJOL)

    These data are suggestive of altered calcium metabolism impairing cell membrane stabilization, the vasorelaxing effect of calcium and cell signaling. Altered calcium metabolism may be the major biochemical lesion underlying many pathological and clinical states of lead toxicity. Journal of Biomedical Investigation Vol.

  11. Physiological alterations in UV-irradiated cells: liquid holding recovery

    International Nuclear Information System (INIS)

    Aragao, B.R.

    1980-01-01

    The biochemical and physiological alterations that occur in ultraviolet irradiated cells, during liquid holding have been studied. Incubation in buffer acts not to interfer directly with the mechanic repairs but by promoting metabolic alterations that would block some irreversible and lethal physiological responses. (L.M.J.) [pt

  12. Elk herbivory alters small mammal assemblages in high elevation drainages

    Science.gov (United States)

    Parsons, Elliott W.R.; Maron, John L.; Martin, Thomas E.

    2012-01-01

    Heavy herbivory by ungulates can substantially alter habitat, but the indirect consequences of habitat modification for animal assemblages that rely on that habitat are not well studied. This is a particularly important topic given that climate change can alter plant–herbivore interactions.

  13. Cortisol stress response and histopathological alteration index in ...

    African Journals Online (AJOL)

    Blood samples of C. gariepinus were collected every seven days and evaluated for stress by measuring cortisol concentration. The gills and liver were studied and scored for Gill Alteration Index (GAI) and Hepatic Alteration Index (HAI), respectively. There was an increase in cortisol level up to the 7th and 14th day among ...

  14. Method for altering the luminescence of a semiconductor

    Science.gov (United States)

    Barbour, J.C.; Dimos, D.B.

    1999-01-12

    A method is described for altering the luminescence of a light emitting semiconductor (LES) device. In particular, a method is described whereby a silicon LES device can be selectively irradiated with a radiation source effective for altering the intensity of luminescence of the irradiated region. 4 figs.

  15. Mapping hydrothermal altered mineral deposits using Landsat 7 ...

    Indian Academy of Sciences (India)

    spatial patterns of alteration makes the 'remote sensing technique' one of the standard procedures in exploration geology, due to its high efficiency and low cost (Yetkin 2003). There are many studies around the world related to hydrothermal alteration mapping using multi- spectral satellite images especially, Landsat and.

  16. Mapping hydrothermal altered mineral deposits using Landsat 7 ...

    Indian Academy of Sciences (India)

    To evaluate the conventional methods for mapping hydrothermal altered deposits by using Landsat 7. ETM+ image in and around ... component analysis using the Crosta technique also enabled us to represent undoubtedly the altered hydroxyl and ..... target detection algorithms for hyperspectral imagery; In: Algorithms and ...

  17. 46 CFR 176.700 - Permission for repairs and alterations.

    Science.gov (United States)

    2010-10-01

    ... repair or replacement, other than replacement in kind, of electrical wiring, fuel lines, tanks, boilers... 46 Shipping 7 2010-10-01 2010-10-01 false Permission for repairs and alterations. 176.700 Section... (UNDER 100 GROSS TONS) INSPECTION AND CERTIFICATION Repairs and Alterations § 176.700 Permission for...

  18. Exemple d'etude geochimique et isotopique de circulations aquiferes en terrain volcanique sous climat semi-aride (Amurga, Gran Canaria, Iles Canaries)

    Science.gov (United States)

    Gasparini, Anne; Custodio, Emilio; Fontes, Jean-Charles; Jimenez, José; Nuñez, JoséAntonio

    1990-03-01

    A hydrochemical and isotopic study of a groundwater flow system in volcanic media has been carried out in the southern part of Gran Canaria (Canary Islands). Monthly samples of precipitation were collected over a two year period at stations distributed all over the island. Sampling of groundwaters took place mainly from drillholes in the Amurga phonolitic massif but also from wells and springs discharging from the volcanic and related detrital formations. The δ 2H vs. δ 18O relationship of the precipitation is close to the "global meteoric water line". Two distinct altitudinal isotopic gradients are observed. On the warm and dry southern slope, the combination of a contribution of saharan dusts and seasprays and of partial evaporation explains the high content of dissolved salts (Cl -, SO 2-4) in precipitation. Additional processes may be invoked as sources of groundwater mineralization: leaching of silicate minerals during infiltration and/or from hydrolysis during the long residence time of the waters in the volcanic rocks. Salt content is increased through a concentration of the percolating solutions by evaporation, as shown by their stable isotope contents ( 18O, 2H). The groundwaters in the phonolitic aquifer are well differentiated from the deeper groundwaters, which are recharged at an altitude of about 1000m above sea level, or even less, if exceptional episodes of rain have a lower heavy isotope content. The interpretation of the 13C contents of soil CO 2, sampled throughout the area, and of the 13C and 14C contents of total dissolved inorganic carbon (TDIC) leads to the concept of an incorporation of pure biogenic carbon under open-system conditions in the Amurga waters. For these groundwaters, high estimates of residence time (ca. 11000 years) can be calculated from the low 14C activities. In the neighbouring valleys, the input of deep "dead" volcanic carbon and the occurrence of mixing do not allow an exact quantification of residence time values. However, they seem to be shorter than those measured for the Amurga waters.

  19. Influence of natural organic matter on the speciation of radionuclides in a geochemistry context; Influence de la matiere organique naturelle sur la speciation des radionucleides en contexte geochimique

    Energy Technology Data Exchange (ETDEWEB)

    Marang, L

    2007-09-15

    The principal aim of this work is the study of the influence of natural organic matter, in particularly humic substances (HS), on the speciation of radionuclides (RN). The studied radionuclides are cobalt (II), europium (III) and uranium (VI). It has been shown that mobility and bioavailability of a metal are related to its speciation. The NICA-Donnan model describes metal ion binding to NOM: it accounts for NOM chemical heterogeneity, competition during binding and ionic strength effects. However the model has been calibrated with a limited number of experimental data for the RN. Indeed there is only a few speciation technique available for the study of the interactions RN-HS. Within the framework of this study, we have developed and optimised speciation technique (Flux Donnan Membrane Technique and the use of an un-solubilized humic acid) in order to acquire new experimental data, we have also studied the effect of the competition on RN speciation and finally we have tested the model capacity to predict the RN behavior in laboratory or in situ. (author)

  20. State-related alterations of gene expression in bipolar disorder

    DEFF Research Database (Denmark)

    Munkholm, Klaus; Vinberg, Maj; Berk, Michael

    2012-01-01

    on comprehensive database searches for studies on gene expression in patients with bipolar disorder in specific mood states, was conducted. We searched Medline, Embase, PsycINFO, and The Cochrane Library, supplemented by manually searching reference lists from retrieved publications. Results:  A total of 17......Munkholm K, Vinberg M, Berk M, Kessing LV. State-related alterations of gene expression in bipolar disorder: a systematic review. Bipolar Disord 2012: 14: 684-696. © 2012 The Authors. Journal compilation © 2012 John Wiley & Sons A/S. Objective:  Alterations in gene expression in bipolar disorder...... have been found in numerous studies. It is unclear whether such alterations are related to specific mood states. As a biphasic disorder, mood state-related alterations in gene expression have the potential to point to markers of disease activity, and trait-related alterations might indicate...

  1. Hydrothermal alteration in Dumoga Barat, Bolaang Mongondow area North Sulawesi

    International Nuclear Information System (INIS)

    Agus Harjanto' Sutanto; Sutarto; Achmad Subandrio; I Made Suasta; Juanito Salamat; Giri Hartono; Putu Suputra; I Gde Basten; Muhammad Fauzi; Rosdiana

    2016-01-01

    Bolaang Mongondow is located in central north Sulawesi arm, which is composed of Neogen magmatic arc and potentially contain economic minerals. This condition is behind the research purpose to study the mineral resources potencies. Research aim is to study alteration caused by hydrothermal process and its relation with gold (Au) deposit based on field study and laboratory analysis. Methodologies used for the research are literature study, geological survey, rocks sampling, laboratory analysis, and data processing. Research area is a multiply diorite intrusion complex. Andesite, volcaniclastic rocks, and dacite, the older rocks, were intruded by this complex. Later, dacitic tuff, volcanic sandstone, and alluvium deposited above them. There are three measured and mapped major faults heading NE-SW crossed by E-W fault and NW-SE fault lately crossed all the older faults. Early stage hydrothermal alteration related to the existence of young quartz diorite, showing alteration stage from the potassic center to distal prophylatic. Final stage hydrothermal alteration consist of argilic, advanced argilic, and silica-clay mineral±magnetite±chlorite alteration overlapping the earlier alteration. Mineralization of Cu-Au±Ag in central part of research area or Tayap-Kinomaligan area is mostly associated with potassic altered young quartz diorite and crossed by parallel and stock worked quartz-magnetite-chalcopyrite±bornite vein. (author)

  2. Antiherbivore defenses alter natural selection on plant reproductive traits.

    Science.gov (United States)

    Thompson, Ken A; Johnson, Marc T J

    2016-04-01

    While many studies demonstrate that herbivores alter selection on plant reproductive traits, little is known about whether antiherbivore defenses affect selection on these traits. We hypothesized that antiherbivore defenses could alter selection on reproductive traits by altering trait expression through allocation trade-offs, or by altering interactions with mutualists and/or antagonists. To test our hypothesis, we used white clover, Trifolium repens, which has a Mendelian polymorphism for the production of hydrogen cyanide-a potent antiherbivore defense. We conducted a common garden experiment with 185 clonal families of T. repens that included cyanogenic and acyanogenic genotypes. We quantified resistance to herbivores, and selection on six floral traits and phenology via male and female fitness. Cyanogenesis reduced herbivory but did not alter the expression of reproductive traits through allocation trade-offs. However, the presence of cyanogenic defenses altered natural selection on petal morphology and the number of flowers within inflorescences via female fitness. Herbivory influenced selection on flowers and phenology via female fitness independently of cyanogenesis. Our results demonstrate that both herbivory and antiherbivore defenses alter natural selection on plant reproductive traits. We discuss the significance of these results for understanding how antiherbivore defenses interact with herbivores and pollinators to shape floral evolution. © 2016 The Author(s). Evolution © 2016 The Society for the Study of Evolution.

  3. Rare earth impact on glass structure and alteration kinetics

    International Nuclear Information System (INIS)

    Molieres, E.

    2012-01-01

    This work is related to the question of the geological deep repository of high-level waste glass. These wastes include fission products and minor actinides, elements which can be simulated by rare earths. As new glass compositions could enable increased rare earth concentrations, it is crucial to know and understand rare earth impact on glass structure on the one hand, and on glass alteration kinetics or their incorporation into an altered layer. This work studied simplified borosilicate glasses in order to limit synergetic effects between rare earths and other elements. Various complementary techniques were used to characterize pristine and altered glasses (solid-high resolution NMR, Raman spectroscopy, fluorescence, SIMS, SAXS). Firstly, the structural role of a rare earth is discussed and is compared to a calcium cation. The local environment of rare earths is also probed. Secondly, rare earth (nature and concentration) impact on several alteration regimes was studied (initial rate, rate drop). Then, after alteration, rare earth elements being retained within the altered layer, the structural impact of rare earth elements (and their local environment) in this alteration layer was also investigated. (author) [fr

  4. Altered taste perception and nutritional status among hemodialysis patients.

    Science.gov (United States)

    Lynch, Katherine E; Lynch, Rebecca; Curhan, Gary C; Brunelli, Steven M

    2013-07-01

    The objective of this study was to examine the association between altered taste perception and nutritional status among hemodialysis patients. We performed a post hoc analysis of data from the Hemodialysis study (n = 1,745). Taste perception was assessed at baseline and then updated annually using an item from a quality of life survey that asked "During the past 4 weeks, to what extent were you bothered by loss of taste?" Responses were categorized as normal taste perception if subjects answered "not at all" or altered taste perception if they reported any degree of bother. Time-updated logistic regression models were used to evaluate predictors of altered taste perception. Time-updated linear regression models were used to examine the association between altered taste perception and indices of nutritional status. Multivariable proportional hazards and Poisson models were used to assess association between altered taste perception and mortality and hospitalization, respectively. At baseline, 34.6% reported altered taste perception, which was associated with poorer baseline nutritional status. On time-updated analysis, altered taste perception was associated with a persistently higher proportion of subjects requiring enteral nutritional supplements and lower serum albumin, serum creatinine, normalized protein catabolic rate, protein intake, sodium intake, and mid-arm muscle circumference. Altered taste perception at baseline was independently associated with increased all-cause mortality: adjusted hazard ratio (95% confidence interval) of 1.17 (1.01-1.37), although not with increased rate of hospitalization. Altered taste perception was common among prevalent hemodialysis patients and was independently associated with poorer indices of nutritional status and increased all-cause mortality. Copyright © 2013 National Kidney Foundation, Inc. Published by Elsevier Inc. All rights reserved.

  5. realisation d'un programme de simulation du comportement ...

    African Journals Online (AJOL)

    D'autre part, un programme informatique a été élaboré et peut être utilisé pour calculer les variations de la température intérieure des bâtiments tout au long de la journée et pour les différentes saisons. Ce programme pourra aider les concepteurs à optimiser les températures intérieures avant la construction d'un bâtiment ...

  6. Effet du stress salin sur le comportement physiologique et ...

    African Journals Online (AJOL)

    SARAH

    30 juin 2013 ... rapidement dans les feuilles à partir de 25 mmol de NaCl. Le rapport de sélectivité K+/Na+ a été plus discriminant entre les variétés : Midass a présenté le rapport de sélectivité le plus élevé et Nabeul le rapport de sélectivité le plus faible. Conclusion et application : La variété Nabeul qui est de type piment ...

  7. comportement des nouveaux riz africains face a la pyriculariose

    African Journals Online (AJOL)

    AISA

    Key words : Riz, NERICA variety, blast, inoculation, resistance, Côte d'Ivoire. INTRODUCTION. Les nouveaux riz africains ou NERICA (New Rice for Africa) sont des hybrides interspécifiques. (Oryza glaberrima X O. sativa) mises au point par l'ADRAO (actuellement dénommé Centre. Africain pour le Riz) dans les années 90.

  8. La pathologie rachidienne comporte l'atteinte degenerative ...

    African Journals Online (AJOL)

    % entre 3 et 6 mois, et 24,2% depuis moins de deux mois. L'origine était dégénérative dans 81,7%. Le traitement inflammatoire et /ou antalgique associé aux neuroleptiques a été efficace à plus de 80%. Conclusion : La pathologie rachidienne ...

  9. Effet des additions sur la microstructure et le comportement ...

    African Journals Online (AJOL)

    The friction coefficient was determined under a normal load of 5 N with sliding speed of 11.31 cm/s and at room temperature. The NiAl coating present the lowest coefficient of friction. The incorporation of the particles improves the coefficient of friction. Keywords: Thermal fatigue-erosion-plasma Spray-NiAl coating-friction ...

  10. Comportement monotone et cyclique d'un sable limoneux

    Science.gov (United States)

    Arab, Ahmed

    2009-08-01

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

  11. Comportement des polluants des eaux pluviales urbaines en ...

    African Journals Online (AJOL)

    échange de l'oxygène de l'air avec les eaux usées [20]. 5. CONCLUSION. Ce travail a pour objectif d'évaluer le degré de dégradation de la pollution des eaux usées dans différents milieux (naturel, artificiel et semi naturel) en période humide.

  12. Ecotoxicité et comportement environnemental des lanthanides

    OpenAIRE

    Vignati, Davide,

    2017-01-01

    International audience; Le nom lanthanides indique une série de quinze éléments du tableau périodique allant du lanthane (La) au lutétium (Lu). Les lantha-nides font partie des éléments qualifiés de stratégiques à cause de leur importance dans plusieurs secteurs économiques tels que les énergies vertes, l'électronique et les applications médicales (1). L'utilisation croissante de ces éléments est en train d'en augmenter les concentrations environnementales et d'en altérer les cycles géochimiq...

  13. Comportement des nouveaux riz africains face à la pyriculariose en ...

    African Journals Online (AJOL)

    Cela, dans un contexte épidémique marqué par une pression relativement forte de la pyriculariose maladie fongique due à Magnaporthe grisea (Barr, 1977), très préjudiciable au riz Oriza sativa. Dans le but de prévenir d\\'éventuelles attaques sévères des NERICA par la maladie, une étude d\\'évaluation de leur résistance ...

  14. Gouvernance environnementale locale et comportements économiques

    Directory of Open Access Journals (Sweden)

    Christophe Beaurain

    2004-02-01

    Full Text Available La notion de gouvernance est mobilisée de manière croissante aujourd’hui pour évoquer de nouvelles formes de coopérations entre acteurs de la vie économique et sociale. Appliquée aux questions environnementales, la gouvernance pose à la fois la question de la maîtrise du temps par les acteurs et celle du territoire d’application des décisions prises. On peut donc considérer qu’elle engage un renouvellement de l’articulation entre le temps et l’espace, que doit prendre en compte l’analyse des choix économiques dans ce domaine. L’exemple du bassin d’emploi dunkerquois montre que cette articulation est au cœur d’une participation des entreprises à la gouvernance environnementale.The concept of governance is more and more raised to conjure up new ways of cooperation between actors of the economic and social life. Applied to environmental matters, governance ask both the question of mastery of the time and the one of the territory’s application for taken decisions. We can consider that it engage a renewal of the joint between time and space, that the analysis of economic choices had to take into account. The example of “Dunkerque” show that this joint is the heart of firm’s collaboration in environmental governance.

  15. COMPORTEMENT DE CLONES DE PALMIER A HUILE AU CHAMP ...

    African Journals Online (AJOL)

    AISA

    France). RESUME. Dans la zone dite « savane de Dabou » en Côte d'Ivoire la fusariose du palmier à huile, ..... NASH (S. M.), (W. C.) SNYDER. 1962. Quantitative estimation by plate counts of propagules of the been root rot Fusarium in field soil.

  16. Comportement des polluants des eaux pluviales urbaines en ...

    African Journals Online (AJOL)

    C'est dans ce contexte que s'inscrit le présent travail qui porte sur la dégradation des paramètres organiques (DBO5, DCO, MES, O2, NO-3, pH, T, Fer, turbidité) dans différents milieux : naturel (rivière), canal artificiel, rivière (aux rives revêtues). Le traitement des données, effectué sur les trois sites d'observation sur deux ...

  17. etude des comportements rheologiques des melanges de farine ble ...

    African Journals Online (AJOL)

    liquéfaction de l'amidon et a une très grande capacité de rétention d'eau. Comparées à la farine de blé, les farines composites présentent une plus grande viscosité. La conséquence de cette forte viscosité sur les pains composites est un faible volume car une viscosité élevée s'oppose à la levée sous l'effet de la poussée.

  18. COMPORTEMENT DE CLONES DE PALMIER A HUILE AU CHAMP ...

    African Journals Online (AJOL)

    AISA

    ABSTRACT. OIL PALM CLONES CLONE BEHAVIOUR WITH RESPECT TO FUNGUS (Fusarium oxysporum f. sp elaeidis) ... about important damages powered to carry along a drop of production from 40 to 70 percent in some plots. .... Tableau 1 : Origine et indices moyens des clones de palmier à huile testés au champ sur.

  19. Study of comportment of trioctylphosphine oxide by coat slight chromatography

    International Nuclear Information System (INIS)

    Meddour, Laaldja; Azzouz Abdelkrim

    1996-04-01

    The synthesis and characterisation process of the extractant agent 'Trioctylphosphine oxide' (TOPO) are not very developped in the literature. However, in order to identify this agent (TOPO) in its synthesis process, we attempt several analysis methods. The coat slight chromatography proves the simple and accessible method, that explains the choice of this study. In the present work, we have analysed the TOPO by coat slight chromatography with the intention of finding a better solvent

  20. Effet des additions sur la microstructure et le comportement ...

    African Journals Online (AJOL)

    However, the thermal fatigue and erosion tests were conducted by a cyclic heating Joule effect within the range 100–800 °C degrees and at room temperature with an attack angle of 90° respectively.. Furthermore, the microstructure of all the coatings showed a lamellar morphology, which is typical of the coatings obtained ...

  1. comportement des nouveaux riz africains face a la pyriculariose en ...

    African Journals Online (AJOL)

    AISA

    NERICA 2 à la pyriculariose, contrairement à NERICA 1 qui a été sévèrement attaqué par certaines souches de la maladie. Ces informations ..... Figure 3 : Symptômes provoqués par la souche CD203 de Magnaporthe grisea sur les variétés de riz Maratelli ... la gestion culturale des variétés NERICA 1 et. NERICA 2 en Côte ...

  2. ORIENTATION FIELD RECONSTRUCTION OF ALTERED FINGERPRINT USING ORTHOGONAL WAVELETS

    Directory of Open Access Journals (Sweden)

    Mini M.G.

    2016-11-01

    Full Text Available Ridge orientation field is an important feature for fingerprint matching and fingerprint reconstruction. Matching of the altered fingerprint against its unaltered mates can be done by extracting the available features in the altered fingerprint and using it along with approximated ridge orientation. This paper presents a method for approximating ridge orientation field of altered fingerprints. In the proposed method, sine and cosine of doubled orientation of the fingerprint is decomposed using orthogonal wavelets and reconstructed back using only the approximation coefficients. No prior information about the singular points is needed for orientation approximation. The method is found suitable for orientation estimation of low quality fingerprint images also.

  3. Long-term alteration of basaltic glass: Mechanisms and rates

    Science.gov (United States)

    Parruzot, Benjamin; Jollivet, Patrick; Rébiscoul, Diane; Gin, Stéphane

    2015-04-01

    The long-term behavior study of archaeological artifacts and natural minerals and glasses revealed discrepancies between laboratory and field data. For a better understanding of the cause of these discrepancies and to reinforce the use of basaltic glass as an analog for nuclear waste glasses, this study focuses on the determination of alteration rates and processes of synthetic basaltic glass in residual rate regime. Laboratory batch experiments were performed at high surface-to-volume ratios at 90 and 30 °C for more than 1000 days. In all the experiments, the residual rate regime was reached after about 6 months. The residual alteration rates at 30 and 90 °C were 4.0 ± 1.0 × 10-6 and 9.5 ± 3.2 × 10-6 g·m-2·d-1, respectively. At 90 °C, this residual alteration rate is five orders of magnitude lower than the forward alteration rate (0.8 g·m-2·d-1). Altered powders and monoliths were characterized by Transmission Electron Microscopy and Time-of-Flight Secondary Ion Mass Spectrometry. From glass core to solution, the altered materials are structured as follows: pristine glass, gel (corresponding to the palagonitic layer of natural glasses) and intergranular clays. To assess the passivating properties of this alteration film, we used solid characterization, an isotopically-tagged post-leaching experiment and the measurement of mobile species diffusion coefficients through the alteration film at different stages of reaction using various techniques (solution analysis and X-ray Reflectometry). These characterizations showed that the alteration film formed during residual rate alteration is passivating even without clogged porosity within the gel. Diffusion coefficients of water and alkali metals - respectively diffusing to and from the pristine glass - through the alteration film dropped from 10-20 to 10-19 m2·s-1 during the first alteration stages to 10-25 m2·s-1 in residual rate regime.

  4. Geothermal alteration of clay minerals and shales: diagenesis

    International Nuclear Information System (INIS)

    Weaver, C.E.

    1979-07-01

    The objective of this report is to perform a critical review of the data on the mineral and chemical alterations that occur during diagenesis and low-grade metamorphism of shale and other clay-rich rocks - conditions similar to those expected from emplacement of heat-producing radioactive waste in a geologic repository. The conclusions drawn in this document are that the following type of alterations could occur: smectite alteration, ion mobilization, illitic shales, kaolinite reactions, chlorite reactions, organic reactions, paleotemperatures, low temperature shales, high temperature shales, and phase equilibrium changes

  5. Geothermal alteration of clay minerals and shales: diagenesis

    Energy Technology Data Exchange (ETDEWEB)

    Weaver, C.E.

    1979-07-01

    The objective of this report is to perform a critical review of the data on the mineral and chemical alterations that occur during diagenesis and low-grade metamorphism of shale and other clay-rich rocks - conditions similar to those expected from emplacement of heat-producing radioactive waste in a geologic repository. The conclusions drawn in this document are that the following type of alterations could occur: smectite alteration, ion mobilization, illitic shales, kaolinite reactions, chlorite reactions, organic reactions, paleotemperatures, low temperature shales, high temperature shales, and phase equilibrium changes.

  6. White matter alterations in neurodegenerative and vascular dementia

    International Nuclear Information System (INIS)

    Supprian, T.; Kessler, H.; Falkai, P.; Retz, W.; Roesler, M.; Grunwald, I.; Reith, W.

    2003-01-01

    Due to a significant overlap of the two syndromes, differentiation of degenerative dementia of the Alzheimer-type from vascular dementia may be difficult even when imaging studies are available. White matter changes occur in many patients suffering from Alzheimer's disease. Little is known about the impact of white matter changes on the course and clinical presentation of Alzheimer's disease. High sensitivity of MRI in the detection of white matter alterations may account for over-diagnosing vascular dementia. The clinical significance of white matter alterations in dementia is still a matter of debate. The article reviews current concepts about the role of white matter alterations in dementia. (orig.) [de

  7. Comparative study by infrared spectrometry of the behaviour of Y-H and Y-D groups. Valencies frequency and molecular association constants; Etude comparee par spectrometrie infrarouge du comportement de groupements YH et YD. Frequences de valence et constantes d'association moleculaires

    Energy Technology Data Exchange (ETDEWEB)

    Leicknam, J.P. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1966-02-01

    In the first part of the report a comparison is made of the relative lowering of the frequencies determined using homologous hydrogenated and deuterated vibrators dissolved in various solvents, with the gaseous state as reference. It is confirmed that one always has ({delta}{nu}/{nu}{sub g}){sub YH} {>=} ({delta}{nu}/{nu}{sub g}){sub YD}. Certain results suggest the existence of interactions between vibrational and electronic states, but the different behaviours of OH and OD molecules and of NH and deuterated-N compounds show that the phenomenon is complex. In the second part of the report a quantitative examination is made of about a hundred molecular associations which are formed in solution in an inert solvent by means of hydrogen or deuterium bridges. The proton and deuton donor auto-associations are studied first of all, the association constants K{sub H} are then determined for the proton donors with various acceptors, as are the K{sub D}/K{sub H} ratios obtained after partial substitution in these donors of the hydrogen by deuterium. The results show that it is necessary to distinguish thermo-dynamic effects (which can be calculated when all frequencies of the free dynamic and complexed molecules, are known) and chemical effects connected with the nature of the donors and acceptors; among these latter, the possible formation of 'ionic pairs' has without doubt a great influence on the direction of the isotopic effect. (author) [French] Dans une prerrere partie, en prenant l'etat gazeux comme reference, on compare les abaissements relatifs de frequence determinee avec des vibrateurs hydrogenes et deuteries homologues dissous dans divers solvants. On confirme que l'on a toujours ({delta}{nu}/{nu}{sub g}){sub YH} {>=} ({delta}{nu}/{nu}{sub g}){sub YD}. Certains resultats conduisent a envisager l'existence d'interactions entre etats vibratoires et electroniques, mais le comportement different des molecules OH et OD et des composes NH

  8. Characterizing genomic alterations in cancer by complementary functional associations.

    Science.gov (United States)

    Kim, Jong Wook; Botvinnik, Olga B; Abudayyeh, Omar; Birger, Chet; Rosenbluh, Joseph; Shrestha, Yashaswi; Abazeed, Mohamed E; Hammerman, Peter S; DiCara, Daniel; Konieczkowski, David J; Johannessen, Cory M; Liberzon, Arthur; Alizad-Rahvar, Amir Reza; Alexe, Gabriela; Aguirre, Andrew; Ghandi, Mahmoud; Greulich, Heidi; Vazquez, Francisca; Weir, Barbara A; Van Allen, Eliezer M; Tsherniak, Aviad; Shao, Diane D; Zack, Travis I; Noble, Michael; Getz, Gad; Beroukhim, Rameen; Garraway, Levi A; Ardakani, Masoud; Romualdi, Chiara; Sales, Gabriele; Barbie, David A; Boehm, Jesse S; Hahn, William C; Mesirov, Jill P; Tamayo, Pablo

    2016-05-01

    Systematic efforts to sequence the cancer genome have identified large numbers of mutations and copy number alterations in human cancers. However, elucidating the functional consequences of these variants, and their interactions to drive or maintain oncogenic states, remains a challenge in cancer research. We developed REVEALER, a computational method that identifies combinations of mutually exclusive genomic alterations correlated with functional phenotypes, such as the activation or gene dependency of oncogenic pathways or sensitivity to a drug treatment. We used REVEALER to uncover complementary genomic alterations associated with the transcriptional activation of β-catenin and NRF2, MEK-inhibitor sensitivity, and KRAS dependency. REVEALER successfully identified both known and new associations, demonstrating the power of combining functional profiles with extensive characterization of genomic alterations in cancer genomes.

  9. Alteration behavior of 67 years old tunnel lining concrete

    International Nuclear Information System (INIS)

    Saito, Hiroshi; Hasegawa, Hiroshi; Nakane, Sunao

    1992-01-01

    The objective of this study is to collect data on alteration of concrete under natural environmental conditions. Cementitious materials are examined for utilization in radioactive waste disposal with expectations of long life. To develop a predictive model of alteration behavior, it is important to investigate the alteration of concrete under various natural conditions for a long period of time. Taking into account environmental conditions anticipated for radioactive waste repositories, concrete cores are drilled from tunnel lining concrete 67 years in age. The investigations are conducted from chemical as well as physical points of view using various methods. The concrete examined is found to have been insignificantly altered, maintaining the strength and degree of impermeability hoped for. (orig.)

  10. Raman spectroscopic study of a genetically altered kidney cell

    Science.gov (United States)

    Joshi, Joel; Garcia, Francisco; Centeno, Silvia P.; Joshi, N. V.

    2008-02-01

    A Raman spectroscopic investigation of a genetically altered Human Embryonic Kidney Cell (HEK293) along with a pathologically normal cell has been carried out by a conventional method. The genetic alteration was carried out with a standard protocol by using a Green Fluorescence Protein (GFP). Raman spectra show that there are dramatic differences between the spectrum obtained from a genetically altered cell and that obtained from a pathologically normal cell. The former shows three broad bands; meanwhile the latter shows several sharp peaks corresponding to the ring vibrational modes of Phen, GFP and DNA. The present analysis provides an indication that the force field near Phen located at 64, 65 and 66 was altered during the genetic transformation. The Raman spectrum could be a direct experimental evidence for substantial modifications triggered due to the expression of specific genes.

  11. Violent Video Games Alter Brain Function in Young Men

    Science.gov (United States)

    ... feed News from the RSNA Annual Meeting Violent Video Games Alter Brain Function in Young Men At A ... functional MRI, researchers have found that playing violent video games for one week causes changes in brain function. ...

  12. Diet, lifestyle, and molecular alterations that drive colorectal carcinogenesis

    NARCIS (Netherlands)

    Diergaarde, B.

    2004-01-01

    Environmental factors have been repeatedly implicated in the etiology of colorectal cancer, and much is known about the molecular events involved in colorectal carcinogenesis. The relationships between environmental risk factors and the molecular alterations that drive colorectal carcinogenesis are

  13. The alteration of the BPM, burden neutrality and autonomous greening

    International Nuclear Information System (INIS)

    2009-01-01

    The foundation of the purchase tax on passenger cars (BPM) in the Netherlands is gradually altered from catalogue value to CO2 emission per kilometer of the new car. The tariffs have been established in such a way that they meet the precondition of burden neutrality of the BPM alteration. There is some discussion about this and the first part of this publication will address this issue. The issue of burden neutrality is part of a study by DHV Investment Services (DHV). The first main conclusion of the DHV study is that the alteration is not budget neutral. The study entails an applied welfare analysis of the alteration of the BPM foundation. Some comments on the welfare analysis are provided in the second part of this memo. Another issue that is addressed involves the question if and how the autonomous decrease in CO2 emission of newly sold cars can be established in practice. [nl

  14. Uncoupling proteins 2 and 3 alter mitochondrial membrane ...

    African Journals Online (AJOL)

    Saccharomyces cerevisiae). Total phospholipids were extracted and their fatty acyl composition was analysed. Expression of hUCP2 and hUCP3 significantly altered the mitochondrial phospholipid fatty acyl composition. Palmitoleoyl groups (16:1(n-7)) ...

  15. Photochemical Reaction Altered Cardiac Toxicity of Diesel Exhaust Inhalation

    Science.gov (United States)

    Rationale: Epidemiological studies have indicated an association between urban air pollution exposure and cardiovascular morbidity and mortality. The present study was designed to evaluate the cardiac effects of inhaled diesel exhaust and compared with photochemically altered d...

  16. Statistical Evaluation of Classification Diagrams for Altered Igneous Rocks

    OpenAIRE

    VERMA, SURENDRA P.; RODRÍGUEZ-RÍOS, RODOLFO; GONZÁLEZ-RAMÍREZ, + & ROSALINDA

    2010-01-01

    The International Union of Geological Sciences (IUGS) has proposed recommendations for the classification of relatively fresh volcanic rocks, but with no specific instructions for altered volcanic rocks, other than discouraging the use of the total alkalis versus silica diagram. The Nb/Y-Zr/TiO2 diagram has been in use for the classification of altered rocks now for over 30 years. Recently (during 2007) another diagram (Co-Th) has been proposed to replace this old diagram, particularly for al...

  17. Previous climatic alterations are caused by the sun

    International Nuclear Information System (INIS)

    Groenaas, Sigbjoern

    2003-01-01

    The article surveys the scientific results of previous research into the contribution of the sun to climatic alterations. The author concludes that there is evidence of eight cold periods after the last ice age and that the alterations largely were due to climate effects from the sun. However, these effects are only causing a fraction of the registered global warming. It is assumed that the human activities are contributing to the rest of the greenhouse effect

  18. A Corn Tissue Culture Cell Line with Altered Lipid Metabolism

    OpenAIRE

    Yue-ie C, Hsing; Jack M, Widholm; Robert W, Rinne; Institute of Botany, Academia Sinica; Department of Agronomy, University of Illinois at Urbana; Plant Physiology and Genetics Research Unit, Department of Agriculture, Agricultural Research Service and Department of Agronomy, University of Illinois at Urbana

    1991-01-01

    A variant corn callus line derived from callus which originated from etiolated leaves of Illinois High Oil corn (Zea mays L.) has been identified. The variant corn callus line had increased lipid content concomitant with increased acetyl-CoA carboxylase activity and altered biotin-containing protein patterns relative to the wild type callus. The variant callus line also had altered fatty acid composition concomitant with decreased oleate desaturase activity compared to the wild type callus. T...

  19. Altered anterior visual system development following early monocular enucleation

    Directory of Open Access Journals (Sweden)

    Krista R. Kelly

    2014-01-01

    Conclusions: The novel finding of an asymmetry in morphology of the anterior visual system following long-term survival from early monocular enucleation indicates altered postnatal visual development. Possible mechanisms behind this altered development include recruitment of deafferented cells by crossing nasal fibres and/or geniculate cell retention via feedback from primary visual cortex. These data highlight the importance of balanced binocular input during postnatal maturation for typical anterior visual system morphology.

  20. Hypersexuality or altered sexual preference following brain injury.

    Science.gov (United States)

    Miller, B L; Cummings, J L; McIntyre, H; Ebers, G; Grode, M

    1986-01-01

    Eight patients are described in whom either hypersexuality (four cases) or change in sexual preference (four cases) occurred following brain injury. In this series disinhibition of sexual activity and hypersexuality followed medial basal-frontal or diencephalic injury. This contrasted with the patients demonstrating altered sexual preference whose injuries involved limbic system structures. In some patients altered sexual behaviour may be the presenting or dominant feature of brain injury. Images PMID:3746322

  1. Hypersexuality or altered sexual preference following brain injury.

    OpenAIRE

    Miller, B L; Cummings, J L; McIntyre, H; Ebers, G; Grode, M

    1986-01-01

    Eight patients are described in whom either hypersexuality (four cases) or change in sexual preference (four cases) occurred following brain injury. In this series disinhibition of sexual activity and hypersexuality followed medial basal-frontal or diencephalic injury. This contrasted with the patients demonstrating altered sexual preference whose injuries involved limbic system structures. In some patients altered sexual behaviour may be the presenting or dominant feature of brain injury.

  2. Heavy metals and epigenetic alterations in brain tumors.

    Science.gov (United States)

    Caffo, Maria; Caruso, Gerardo; Fata, Giuseppe La; Barresi, Valeria; Visalli, Maria; Venza, Mario; Venza, Isabella

    2014-12-01

    Heavy metals and their derivatives can cause various diseases. Numerous studies have evaluated the possible link between exposure to heavy metals and various cancers. Recent data show a correlation between heavy metals and aberration of genetic and epigenetic patterns. From a literature search we noticed few experimental and epidemiological studies that evaluate a possible correlation between heavy metals and brain tumors. Gliomas arise due to genetic and epigenetic alterations of glial cells. Changes in gene expression result in the alteration of the cellular division process. Epigenetic alterations in brain tumors include the hypermethylation of CpG group, hypomethylation of specific genes, aberrant activation of genes, and changes in the position of various histones. Heavy metals are capable of generating reactive oxygen assumes that key functions in various pathological mechanisms. Alteration of homeostasis of metals could cause the overproduction of reactive oxygen species and induce DNA damage, lipid peroxidation, and alteration of proteins. In this study we summarize the possible correlation between heavy metals, epigenetic alterations and brain tumors. We report, moreover, the review of relevant literature.

  3. Epidermal growth factor receptor structural alterations in gastric cancer

    International Nuclear Information System (INIS)

    Moutinho, Cátia; Mateus, Ana R; Milanezi, Fernanda; Carneiro, Fátima; Seruca, Raquel; Suriano, Gianpaolo

    2008-01-01

    EGFR overexpression has been described in many human tumours including gastric cancer. In NSCLC patients somatic EGFR mutations, within the kinase domain of the protein, as well as gene amplification were associated with a good clinical response to EGFR inhibitors. In gastric tumours data concerning structural alterations of EGFR remains controversial. Given its possible therapeutic relevance, we aimed to determine the frequency and type of structural alterations of the EGFR gene in a series of primary gastric carcinomas. Direct sequencing of the kinase domain of the EGFR gene was performed in a series of 77 primary gastric carcinomas. FISH analysis was performed in 30 cases. Association studies between EGFR alterations and the clinical pathological features of the tumours were performed. Within the 77 primary gastric carcinomas we found two EGFR somatic mutations and several EGFR polymorphisms in exon 20. Six different intronic sequence variants of EGFR were also found. Four gastric carcinomas showed balanced polysomy or EGFR gene amplification. We verified that gastric carcinoma with alterations of EGFR (somatic mutations or copy number variation) showed a significant increase of tumour size (p = 0.0094) in comparison to wild-type EGFR carcinomas. We demonstrate that EGFR structural alterations are rare in gastric carcinoma, but whenever present, it leads to tumour growth. We considered that searching for EGFR alterations in gastric cancer is likely to be clinically important in order to identify patients susceptible to respond to tyrosine kinase inhibitors

  4. Antagonist effects of calcium on borosilicate glass alteration

    Energy Technology Data Exchange (ETDEWEB)

    Mercado-Depierre, S. [CEA Marcoule, DTCD SPDE LCLT, 30207 Bagnols sur Cèze (France); Angeli, F., E-mail: frederic.angeli@cea.fr [CEA Marcoule, DTCD SPDE LCLT, 30207 Bagnols sur Cèze (France); Frizon, F. [CEA Marcoule, DTCD SECM LP2C, 30207 Bagnols sur Cèze (France); Gin, S. [CEA Marcoule, DTCD SPDE LCLT, 30207 Bagnols sur Cèze (France)

    2013-10-15

    Graphical abstract: Display Omitted -- Highlights: •Kinetic study of glass alteration is investigated in calcium-enriched solutions. •New insights into silicon–calcium interactions in glass/cement systems are proposed. •Glass alteration is controlled by pH, Ca concentration and reaction progress. •Evidence of antagonist effects according to the importance of these parameters. -- Abstract: Numerous studies have been conducted on glass and cement durability in contact with water, but very little work to date has focused directly on interactions between the two materials. These interactions are mostly controlled by silicon–calcium reactivity. However, the physical and chemical processes involved remain insufficiently understood to predict the evolution of coupled glass–cement systems used in several industrial applications. Results are reported from borosilicate glass alteration in calcium-rich solutions. Our data show that four distinct behaviors can be expected according to the relative importance of three key parameters: the pH, the reaction progress (short- or long-term alteration) and the calcium concentration. Glass alteration is thus controlled by specific mechanisms depending on the solution chemistry: calcium complexation at the glass surface, precipitation of calcium silicate hydrates (C–S–H) or calcium incorporation in the altered layer. These findings highlight the impact of silicon–calcium interactions on glass durability and open the way for a better understanding of glass–cement mixing in civil engineering applications as well as in nuclear waste storage.

  5. Development of gypsum alteration on marble and limestone

    Science.gov (United States)

    McGee, E.S.

    1996-01-01

    Blackened alteration crusts of gypsum plus particulates that form on sheltered areas on marble and limestone buildings pose a challenge for rehabilitation and cleaning. Fresh marble and limestone samples exposed at monitored exposure sites present conditions of simple geometry and well-documented exposures but have short exposure histories (one to five years). The gypsum alteration crusts that develop on these samples provide insight into the early stages and rate of alteration crust formation. Alteration crusts from buildings give a longer, but less well known exposure history and present much more complex surfaces for gypsum accumulation. Integrated observations and measurements of alteration crusts from exposure samples and from buildings identify four factors that are important in the formation and development of alteration crusts on marble and limestone: (1) pollution levels, (2) exposure to rain or washing, (3) geometry of exposure of the stone surface, and (4) permeability of the stone. The combination of these factors contributes to both the distribution and the physical characteristics of the gypsum crusts which may affect cleaning decisions.

  6. Detection Of Alterations In Audio Files Using Spectrograph Analysis

    Directory of Open Access Journals (Sweden)

    Anandha Krishnan G

    2015-08-01

    Full Text Available The corresponding study was carried out to detect changes in audio file using spectrograph. An audio file format is a file format for storing digital audio data on a computer system. A sound spectrograph is a laboratory instrument that displays a graphical representation of the strengths of the various component frequencies of a sound as time passes. The objectives of the study were to find the changes in spectrograph of audio after altering them to compare altering changes with spectrograph of original files and to check for similarity and difference in mp3 and wav. Five different alterations were carried out on each audio file to analyze the differences between the original and the altered file. For altering the audio file MP3 or WAV by cutcopy the file was opened in Audacity. A different audio was then pasted to the audio file. This new file was analyzed to view the differences. By adjusting the necessary parameters the noise was reduced. The differences between the new file and the original file were analyzed. By adjusting the parameters from the dialog box the necessary changes were made. The edited audio file was opened in the software named spek where after analyzing a graph is obtained of that particular file which is saved for further analysis. The original audio graph received was combined with the edited audio file graph to see the alterations.

  7. Anatomical study of minor alterations in neonate vocal folds.

    Science.gov (United States)

    Silva, Adriano Rezende; Machado, Almiro José; Crespo, Agrício Nubiato

    2014-01-01

    Minor structural alterations of the vocal fold cover are frequent causes of voice abnormalities. They may be difficult to diagnose, and are expressed in different manners. Cases of intracordal cysts, sulcus vocalis, mucosal bridge, and laryngeal micro-diaphragm form the group of minor structural alterations of the vocal fold cover investigated in the present study. The etiopathogenesis and epidemiology of these alterations are poorly known. To evaluate the existence and anatomical characterization of minor structural alterations in the vocal folds of newborns. 56 larynxes excised from neonates of both genders were studied. They were examined fresh, or defrosted after conservation via freezing, under a microscope at magnifications of 25× and 40×. The vocal folds were inspected and palpated by two examiners, with the aim of finding minor structural alterations similar to those described classically, and other undetermined minor structural alterations. Larynges presenting abnormalities were submitted to histological examination. Six cases of abnormalities were found in different larynges: one (1.79%) compatible with a sulcus vocalis and five (8.93%) compatible with a laryngeal micro-diaphragm. No cases of cysts or mucosal bridges were found. The observed abnormalities had characteristics similar to those described in other age groups. Abnormalities similar to sulcus vocalis or micro-diaphragm may be present at birth. Copyright © 2014 Associação Brasileira de Otorrinolaringologia e Cirurgia Cérvico-Facial. Published by Elsevier Editora Ltda. All rights reserved.

  8. Altered mitochondrial function after acute alteration of the endogenous insulin/glucagon ratio

    International Nuclear Information System (INIS)

    Rohweder-Dunn, G.; Aprille, J.R.

    1986-01-01

    Mannoheptulose (MH) affects pancreatic Islet cells to cause a drop in serum insulin and a rise in glucagon. This effect peaks 1 hr after injection and results in a 3-fold increase in serum glucose. Here they examined whether metabolic functions of liver mitochondria (mito) are altered by this change in hormone status. Rats fed ad lib on 12 hr light/dark cycles were given MH (2g/kg) or vehicle i.p. during the first 2 hrs of the light cycle. Liver mito were isolated 1 hr later. Acid-extracts were assayed for ATP+ADP+AMP (nmol/mg prot). Citrulline synthesis and pyruvate carboxylation rates (nmol/min/mg prot) were assayed by following H[ 14 C]O 3 - fixation in appropriate media. State 3 and 2,4-DNP-uncoupled respiratory rates (1/2 nmol O 2 /min/mg prot) were assayed polarographically with succinate. The effects of MH on mito are comparable to reported effects of glucagon injection. MH evokes acute reciprocal changes in insulin and glucagon that are highly reproducible. Thus, MH offers an interesting model for studying the effect of endogenous hormones on mito functions

  9. Efficacité d'un exutoire de dévalaison pour smolts de saumon atlantique (Salmo salar L. et comportement des poissons au niveau de l'aménagement hydroélectrique de Bedous sur le gave d'Aspe étudiés par la technique de marquage-recapture et par radiotélémétrie

    Directory of Open Access Journals (Sweden)

    CHANSEAU M.

    1999-04-01

    Full Text Available Deux expérimentations ont été conduites en 1995 et 1998 au niveau de la prise d'eau de l'aménagement hydroélectrique de Bedous sur le Gave d'Aspe afin de tester l'efficacité d'un exutoire de dévalaison pour smolts de saumon atlantique (Salmo salar L.. Le dispositif de dévalaison est situé en rive droite à proximité immédiate du plan des grilles. Le débit moyen alimentant l'exutoire a varié au cours de l'étude de 0,4 m3/s à 1,2 m3/s ce qui correspond à 1,6 % à 4,3 % du débit turbiné. Lefficacité du dispositif a été évaluée grâce à la technique de marquage-recapture. Le comportement des smolts dans le canal d'amenée a été suivi par radiotélémétrie. L'efficacité de l'exutoire (moyenne : 17 % s'est révélée très faible en 1995 â cause de conditions hydrauliques défavorables. Un mur déflecteur a été mis en place en 1997 afin de modifier l'écoulement dans le canal et améliorer le guidage des poissons vers l'entrée du dispositif de dévalaison. L'efficacité de l'exutoire est passée à 55 %. Le comportement des poissons à l'amont immédiat des grilles de prise d'eau est très dépendant des conditions hydrodynamiques dans le canal d'amenée. L'efficacité de l'exutoire semble croître avec la longueur des poissons, la proportion des classes de taille inférieures à 19 cm étant plus faible sur les poissons piégés que sur les poissons lâchés. Cette sélection est très certainement liée à l'espacement relativement important des barreaux des grilles de la prise d'eau (30 mm qui malgré le courant tangentiel au plan de grilles demeurent plus perméables aux individus les plus petits. L'éclairage de l'entrée de l'exutoire ne paraît pas avoir d'influence sur les déplacements des poissons radiomarqués dans le canal d'amenée, le facteur hydraulique étant prépondérant. Il modifie cependant les rythmes de passage des poissons par l'exutoire.

  10. Evaluation of bentonite alteration due to interactions with iron. Sensitivity analyses to identify the important factors for the bentonite alteration

    International Nuclear Information System (INIS)

    Sasamoto, Hiroshi; Wilson, James; Sato, Tsutomu

    2013-01-01

    Performance assessment of geological disposal systems for high-level radioactive waste requires a consideration of long-term systems behaviour. It is possible that the alteration of swelling clay present in bentonite buffers might have an impact on buffer functions. In the present study, iron (as a candidate overpack material)-bentonite (I-B) interactions were evaluated as the main buffer alteration scenario. Existing knowledge on alteration of bentonite during I-B interactions was first reviewed, then the evaluation methodology was developed considering modeling techniques previously used overseas. A conceptual model for smectite alteration during I-B interactions was produced. The following reactions and processes were selected: 1) release of Fe 2+ due to overpack corrosion; 2) diffusion of Fe 2+ in compacted bentonite; 3) sorption of Fe 2+ on smectite edge and ion exchange in interlayers; 4) dissolution of primary phases and formation of alteration products. Sensitivity analyses were performed to identify the most important factors for the alteration of bentonite by I-B interactions. (author)

  11. An alter-centric perspective on employee innovation: The importance of alters' creative self-efficacy and network structure.

    Science.gov (United States)

    Grosser, Travis J; Venkataramani, Vijaya; Labianca, Giuseppe Joe

    2017-09-01

    While most social network studies of employee innovation behavior examine the focal employees' ("egos'") network structure, we employ an alter-centric perspective to study the personal characteristics of employees' network contacts-their "alters"-to better understand employee innovation. Specifically, we examine how the creative self-efficacy (CSE) and innovation behavior of employees' social network contacts affects their ability to generate and implement novel ideas. Hypotheses were tested using a sample of 144 employees in a U.S.-based product development organization. We find that the average CSE of alters in an employee's problem solving network is positively related to that employee's innovation behavior, with this relationship being mediated by these alters' average innovation behavior. The relationship between the alters' average innovation behavior and the employee's own innovation behavior is strengthened when these alters have less dense social networks. Post hoc results suggest that having network contacts with high levels of CSE also leads to an increase in ego's personal CSE 1 year later in cases where the employee's initial level of CSE was relatively low. Implications for theory and practice are discussed. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  12. Mapping advanced argillic alteration at Cuprite, Nevada, using imaging spectroscopy

    Science.gov (United States)

    Swayze, Gregg A.; Clark, Roger N.; Goetz, Alexander F.H.; Livo, K. Eric; Breit, George N.; Kruse, Fred A.; Sutley, Stephen J.; Snee, Lawrence W.; Lowers, Heather A.; Post, James L.; Stoffregen, Roger E.; Ashley, Roger P.

    2014-01-01

    Mineral maps based on Airborne Visible/Infrared Imaging Spectrometer (AVIRIS) data were used to study late Miocene advanced argillic alteration at Cuprite, Nevada. Distributions of Fe-bearing minerals, clays, micas, sulfates, and carbonates were mapped using the Tetracorder spectral-shape matching system. The Al content of white micas increases toward altered areas and near intrusive rocks. Alunite composition varies from pure K to intimate mixtures of Na-K endmembers with subpixel occurrences of huangite, the Ca analogue of alunite. Intimately mixed Na-K alunite marks areas of relatively lower alteration temperature, whereas co-occurring Na-alunite and dickite may delineate relict hydrothermal conduits. The presence of dickite, halloysite, and well-ordered kaolinite, but absence of disordered kaolinite, is consistent with acidic conditions during hydrothermal alteration. Partial lichen cover on opal spectrally mimics chalcedony, limiting its detection to lichen-free areas. Pods of buddingtonite are remnants of initial quartz-adularia-smectite alteration. Thus, spectral maps provide a synoptic view of the surface mineralogy, and define a previously unrecognized early steam-heated hydrothermal event.Faulting and episodes of hydrothermal alteration at Cuprite were intimately linked to upper plate movements above the Silver Peak-Lone Mountain detachment and growth, collapse, and resurgence of the nearby Stonewall Mountain volcanic complex between 8 and 5 Ma. Isotopic dating indicates that hydrothermal activity started at least by 7.61 Ma and ended by about 6.2 Ma. Spectral and stable isotope data suggest that Cuprite is a late Miocene low-sulfidation adularia-sericite type hot spring deposit overprinted by late-stage, steam-heated advanced argillic alteration formed along the margin of the Stonewall Mountain caldera.

  13. Diabetes mellitus and oral mucosa alterations: prevalence and risk factors.

    Science.gov (United States)

    Bastos, Alliny de Souza; Leite, Andressa Rosa Perin; Spin-Neto, Rubens; Nassar, Patrícia Oehlmeyer; Massucato, Elaine Maria Sgavioli; Orrico, Silvana Regina Perez

    2011-04-01

    To investigate the prevalence of oral mucosa alterations in patients with type 2 diabetes and to identify possible risk factors related to oral mucosa alterations. 146 patients with type 2 diabetes and 111 age- and gender-matched healthy controls subjects were consecutively recruited from Araraquara School of Dentistry to answer a structured questionnaire designed to collect demographic data as well as current and former history of diabetes. Clinical examination of the oral mucosa was carried out by a stomatologist. A higher prevalence of oral mucosa alterations was found in patients with diabetes than in patients without diabetes (pdiabetes (odds ratio 9.9 IC 5.11-19.16) and smoking habit (odds ratio 3.17 IC 1.42-7.12) increased the odds of oral mucosa alterations significantly. Patients with diabetes mellitus not only showed an increased prevalence of oral mucosa alterations but also a significant percentage of potentially malignant disorders. These findings elucidate the necessity of regular clinical examination to ensure early diagnosis and prompt management of oral mucosa lesions in patients with diabetes. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

  14. Altered States of Consciousness during an Extreme Ritual

    Science.gov (United States)

    Loewald, Tonio; Comber, Evelyn M.; Hanson, Sarah A.; Pruitt, Bria

    2016-01-01

    Extreme rituals (body-piercing, fire-walking, etc.) are anecdotally associated with altered states of consciousness—subjective alterations of ordinary mental functioning (Ward, 1984)—but empirical evidence of altered states using both direct and indirect measures during extreme rituals in naturalistic settings is limited. Participants in the “Dance of Souls”, a 3.5-hour event during which participants received temporary piercings with hooks or weights attached to the piercings and danced to music provided by drummers, responded to measures of two altered states of consciousness. Participants also completed measures of positive and negative affect, salivary cortisol (a hormone associated with stress), self-reported stress, sexual arousal, and intimacy. Both pierced participants (pierced dancers) and non-pierced participants (piercers, piercing assistants, observers, drummers, and event leaders) showed evidence of altered states aligned with transient hypofrontality (Dietrich, 2003; measured with a Stroop test) and flow (Csikszentmihalyi, 1990; Csikszentmihalyi & Csikszentmihalyi, 1990; measured with the Flow State Scale). Both pierced and non-pierced participants also reported decreases in negative affect and psychological stress and increases in intimacy from before to after the ritual. Pierced and non-pierced participants showed different physiological reactions, however, with pierced participants showing increases in cortisol and non-pierced participants showing decreases from before to during the ritual. Overall, the ritual appeared to induce different physiological effects but similar psychological effects in focal ritual participants (i.e., pierced dancers) and in participants adopting other roles. PMID:27175897

  15. Altered States of Consciousness during an Extreme Ritual.

    Directory of Open Access Journals (Sweden)

    Ellen M Lee

    Full Text Available Extreme rituals (body-piercing, fire-walking, etc. are anecdotally associated with altered states of consciousness-subjective alterations of ordinary mental functioning (Ward, 1984-but empirical evidence of altered states using both direct and indirect measures during extreme rituals in naturalistic settings is limited. Participants in the "Dance of Souls", a 3.5-hour event during which participants received temporary piercings with hooks or weights attached to the piercings and danced to music provided by drummers, responded to measures of two altered states of consciousness. Participants also completed measures of positive and negative affect, salivary cortisol (a hormone associated with stress, self-reported stress, sexual arousal, and intimacy. Both pierced participants (pierced dancers and non-pierced participants (piercers, piercing assistants, observers, drummers, and event leaders showed evidence of altered states aligned with transient hypofrontality (Dietrich, 2003; measured with a Stroop test and flow (Csikszentmihalyi, 1990; Csikszentmihalyi & Csikszentmihalyi, 1990; measured with the Flow State Scale. Both pierced and non-pierced participants also reported decreases in negative affect and psychological stress and increases in intimacy from before to after the ritual. Pierced and non-pierced participants showed different physiological reactions, however, with pierced participants showing increases in cortisol and non-pierced participants showing decreases from before to during the ritual. Overall, the ritual appeared to induce different physiological effects but similar psychological effects in focal ritual participants (i.e., pierced dancers and in participants adopting other roles.

  16. Timescales and settings for alteration of chondritic meteorites

    Energy Technology Data Exchange (ETDEWEB)

    Krot, A N; Hutcheon, I D; Brearley, A J; Pravdivtseva, O V; Petaev, M I; Hohenberg, C M

    2005-11-16

    Most groups of chondritic meteorites experienced diverse styles of secondary alteration to various degrees that resulted in formation of hydrous and anhydrous minerals (e.g., phyllosilicates, magnetite, carbonates, ferrous olivine, hedenbergite, wollastonite, grossular, andradite, nepheline, sodalite, Fe,Ni-carbides, pentlandite, pyrrhotite, Ni-rich metal). Mineralogical, petrographic, and isotopic observations suggest that the alteration occurred in the presence of aqueous solutions under variable conditions (temperature, water/rock ratio, redox conditions, and fluid compositions) in an asteroidal setting, and, in many cases, was multistage. Although some alteration predated agglomeration of the final chondrite asteroidal bodies (i.e. was pre-accretionary), it seems highly unlikely that the alteration occurred in the solar nebula, nor in planetesimals of earlier generations. Short-lived isotope chronologies ({sup 26}Al-{sup 26}Mg, {sup 53}Mn-{sup 53}Cr, {sup 129}I-{sup 129}Xe) of the secondary minerals indicate that the alteration started within 1-2 Ma after formation of the Ca,Al-rich inclusions and lasted up to 15 Ma. These observations suggest that chondrite parent bodies must have accreted within the first 1-2 Ma after collapse of the protosolar molecular cloud and provide strong evidence for an early onset of aqueous activity on these bodies.

  17. The genetic alteration of retinoblastoma gene in esophageal cancer

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Jae Il; Shim, Yung Mok; Kim, Chang Min [Korea Cancer Center Hospital of Korea Atomic Energy Research Institute, Taejon (Korea, Republic of)

    1994-12-01

    Retinoblastoma(RB) gene is the prototype of tumor suppressor gene and it`s alteration have been frequently observed in a large number of human tumors. To investigate the role of RB in esophageal cancer, we studied 36 esophageal cancer tissues with Southern blot analysis to detect gross LOH and PCR-SSCP method to find minute LOH and mutation, if any. In the cases with abnormalities, the nucleotide sequence analysis was performed. Allelic loss of chromosome 13q14 occurred in 20 out of 32 informative cases (62.5%) by Southern analysis. Furthermore, PCR-LOH added three positive cases. Mobility shift by PCR-SSCP was observed in one case at exon 22, which showed 1 bp deletion in codon 771 of RB gene resulting in frame shift mutation. Besides, nine PCR-band alteration in tumor tissue compared with normal tissue were observed in exon 14 and 22, but mutation was not found on sequencing analysis suggesting the epigenetic alteration in tumor tissue. Analysis of the clinical data did not show any difference depending upon RB alteration. However, the total incidence of RB gene may play an important role in the development of esophageal cancer. The main genetic alteration of RB gene was deletion detected by Southern blot and one bp deletion leading to frame shift was also observed. 8 figs, 5 tabs. (Author).

  18. Hydrothermal surface alteration in the Copahue Geothermal Field (Argentina)

    Energy Technology Data Exchange (ETDEWEB)

    Mas, Graciela R.; Mas, Luis C.; Bengochea, Leandro

    1996-01-24

    In the area of the Copahue Geothermal Field, there are five active geothermal manifestations, which mainly consist of fumaroles, hot springs and mud pots. Four of these manifestations are located in Argentina: Las Máquinas, Termas de Copahue, Las Maquinitas and El Anfiteatro, and the fifth on the Chilean side: Chancho Co. All of them present a strong acid sulfate country rock alteration, characterized by the assemblage alunite + kaolinite + quartz + cristobalite + pyrite + sulfur + jarosite, as the result of the base leaching by fluids concentrated in H2SO4 by atmospheric oxidation at the water table in a steam heated environment of H2S released by deeper boiling fluids. Another alteration zone in this area, called COP-2, is a fossil geothermal manifestation which shows characteristics of neutral to alkaline alteration represented mainly by the siliceous sinter superimposed over the acid alteration. The mineralogy and zoning of these alteration zones, and their relation with the hidrothermal solutions and the major structures of the area are analized.

  19. Mechanisms for altered carnitine content in hypertrophied rat hearts

    International Nuclear Information System (INIS)

    Reibel, D.K.; O'Rourke, B.; Foster, K.A.

    1987-01-01

    Carnitine levels are reduced in hypertrophied hearts of rats subjected to aortic constriction (banding) and evaluated in hypertrophied hearts of spontaneously hypertensive rats (SHR). In an attempt to determine the mechanisms for these alterations, L-[ 14 C]carnitine transport was examined in isolated perfused hearts. Total carnitine uptake was significantly reduced by ∼20% in hypertrophied hearts of banded rats at all perfusate carnitine concentrations employed. The reduction in total uptake was due to a 40% reduction in carrier-mediated carnitine uptake with no difference in uptake by diffusion. In contrast, carnitine uptake was not altered in isolated hypertrophied hearts of SHR. However, serum carnitine levels were elevated in SHR, which could result in increased myocardial carnitine uptake in vivo. The data suggest that altered carnitine content in hypertrophied hearts of aortic-banded rats is due to an alteration in the carrier-mediated carnitine transport system in the myocardium. However, altered carnitine content in hypertrophied hearts of SHR is not due to a change in the carnitine transport system per se but may rather be due to a change in serum carnitine levels

  20. Power loss analysis in altered tooth-sum spur gearing

    Directory of Open Access Journals (Sweden)

    Sachidananda H. K.

    2018-01-01

    Full Text Available The main cause of power loss or dissipation of heat in case of meshed gears is due to friction existing between gear tooth mesh and is a major concern in low rotational speed gears, whereas in case of high operating speed the power loss taking place due to compression of air-lubricant mixture (churning losses and windage losses due to aerodynamic trial of air lubricant mixture which controls the total efficiency needs to be considered. Therefore, in order to improve mechanical efficiency it is necessary for gear designer during gear tooth optimization to consider these energy losses. In this research paper the power loss analysis for a tooth-sum of 100 altered by ±4% operating between a specified center distance is considered. The results show that negative altered tooth-sum gearing performs better as compared to standard and positive altered tooth-sum gearing.

  1. Lytological characterization and hydrothermal alteration Infiernillo porphyry, provincia Mendoza, Argentina

    International Nuclear Information System (INIS)

    Gomez, A.; Rubinstein, N.; Kleiman, L.. E.mail: kleiman@cae.cnea.gov.ar

    2007-01-01

    El Infiernillo porphyry copper and Mo deposit, in southern Mendoza, Argentina is hosted by ignimbrites of the Cochico Group (lower Permian). The alteration zone consists of a small central quartz neck with appreciable hematite surrounded by an intense quartz-injected zone with local pervasive potassic alteration. Outwards, there is a well-developed phyllic halo with intense bleaching which consists of pervasive and vein-type silicification, sericitization and pyritization. In the outer part of the alteration zone, small polymetallic veins with pyrite, arsenopyrite, galena and minor, chalcopyrite, sphalerite and electrum in quartz gangue crop out. New field, petro-mineralogic and geochemical data confirmed that the host rocks are equivalent to the dacitic and rhyodacitic ignimbrites of the Toba Vieja Gorda Member (Yacimiento Los Reyunos Formation, Cochico Group)

  2. Altered cortical causality after remifentanil administration in healthy volunteers

    DEFF Research Database (Denmark)

    Khodayari-Rostamabad, Ahmad; Graversen, Carina; Olesen, Soren S

    2014-01-01

    Alterations in cortical causality information flow induced by remifentanil infusion in healthy volunteers was investigated in a placebo-controlled double-blind cross-over study. For each of the 21 enrolled male subjects, 2.5 minutes of resting electroencephalography (EEG) data were collected before...... being reproducible between the two baseline recordings, several PSI features were altered by remifentanil administration in comparison to placebo. Furthermore, several of the PSI features altered by remifentanil were correlated to changes in both CRT and pain scores. The results indicate...... that remifentanil administration influence the information flow between several brain areas. Hence, the EEG causality approach offers the potential to assist in deciphering the cortical effects of remifentanil administration....

  3. Rheumatoid cachexia and other nutritional alterations in rheumatologic diseases.

    Science.gov (United States)

    Hurtado-Torres, Gilberto Fabián; González-Baranda, Lourdes Larisa; Abud-Mendoza, Carlos

    2015-01-01

    The prevalence of nutritional alterations in rheumatologic diseases ranges from 4 to 95%, depending on the detection method used. Formerly described as the single term rheumatoid cachexia, nutritional alterations can currently be grouped and subdivided based on the physiopathological mechanisms involved: chronic disease-related inflammatory conditions (cachexia), malnutrition associated to acute malnutrition inflammatory conditions (protein-caloric malnutrition) and starvation-related malnutrition. Clinical manifestations of malnutrition associated to rheumatic diseases vary from the patient with low weight or overweight and obesity; with lean body mass depletion as well as functional repercussions, and impact of quality of life as a common denominator. Additionally, the associated increase in body fat mass increases the risk for cardiovascular morbidity. A multidisciplinary approach towards rheumatic diseases should include aspects oriented towards prevention, early identification, diagnosis and correction of nutritional alterations. Copyright © 2014 Elsevier España, S.L.U. All rights reserved.

  4. Cocaine triggers epigenetic alterations in the corticostriatal circuit.

    Science.gov (United States)

    Sadri-Vakili, Ghazaleh

    2015-12-02

    Acute and repeated exposure to cocaine induces long-lasting alterations in neural networks that underlie compulsive drug seeking and taking. Cocaine exposure triggers complex adaptations in the brain that are mediated by dynamic patterns of gene expression that are translated into enduring changes. Recently, epigenetic modifications have been unveiled as critical mechanisms underlying addiction that contribute to drug-induced plasticity by regulating gene expression. These alterations are also now linked to the heritability of cocaine-induced phenotypes. This review focuses on how changes in the epigenome, such as altered DNA methylation, histone modifications, and microRNAs, regulate transcription of specific genes that contribute to cocaine addiction. Copyright © 2014 Elsevier B.V. All rights reserved.

  5. Small molecule alteration of RNA sequence in cells and animals.

    Science.gov (United States)

    Guan, Lirui; Luo, Yiling; Ja, William W; Disney, Matthew D

    2017-10-18

    RNA regulation and maintenance are critical for proper cell function. Small molecules that specifically alter RNA sequence would be exceptionally useful as probes of RNA structure and function or as potential therapeutics. Here, we demonstrate a photochemical approach for altering the trinucleotide expanded repeat causative of myotonic muscular dystrophy type 1 (DM1), r(CUG) exp . The small molecule, 2H-4-Ru, binds to r(CUG) exp and converts guanosine residues to 8-oxo-7,8-dihydroguanosine upon photochemical irradiation. We demonstrate targeted modification upon irradiation in cell culture and in Drosophila larvae provided a diet containing 2H-4-Ru. Our results highlight a general chemical biology approach for altering RNA sequence in vivo by using small molecules and photochemistry. Furthermore, these studies show that addition of 8-oxo-G lesions into RNA 3' untranslated regions does not affect its steady state levels. Copyright © 2017 Elsevier Ltd. All rights reserved.

  6. Altered mental status as a presentation of juvenile polyposis syndrome

    Directory of Open Access Journals (Sweden)

    Natasha Hansraj

    2015-12-01

    Full Text Available Juvenile polyposis coli (JPC is a rare hereditary disorder in which patients have multiple polyps in the gastrointestinal tract and present most commonly with hematochezia. We describe a 4-year-old with intermittent rectal prolapse presenting with altered mental status and headaches. JPC was diagnosed by the presence of multiple, pedunculated, colonic polyps on colonoscopy; his altered mental status resulted from cerebral venous sinus thrombosis. Although JPC is known to be associated with a protein losing enteropathy (PLE, this usually manifests as merely hypoalbuminemia and protein losses without major clinical sequelae. We present a rare complication of cerebral venous sinus thrombosis which highlights altered mental status as a rare presentation of JPC. To our knowledge, this is the first case report in the literature linking JPC, decreased protein S activity, a single mutation in the methylenetetrahydrofolate reductase gene and cerebral thrombosis.

  7. Brain Rhythms Connect Impaired Inhibition to Altered Cognition in Schizophrenia

    Science.gov (United States)

    Pittman-Polletta, Benjamin R.; Kocsis, Bernat; Vijayan, Sujith; Whittington, Miles A.; Kopell, Nancy J.

    2015-01-01

    In recent years, schizophrenia research has focused on inhibitory interneuron dysfunction at the level of neurobiology, and on cognitive impairments at the psychological level. Reviewing both experimental and computational findings, we show how the temporal structure of the activity of neuronal populations, exemplified by brain rhythms, can begin to bridge these levels of complexity. Oscillations in neuronal activity tie the pathophysiology of schizophrenia to alterations in local processing and large-scale coordination, and these alterations in turn can lead to the cognitive and perceptual disturbances observed in schizophrenia. PMID:25850619

  8. Devices that Alter the Tip Vortex of a Rotor

    Science.gov (United States)

    McAlister, Kenneth W.; Tung, Chee; Heineck, James T.

    2001-01-01

    Small devices were attached near the tip of a hovering rotor blade 'in order to alter the structure and trajectory of the trailing vortex. Stereo particle image velocimetry (PIV) images were used to quantify the wake behind the rotor blade during the first revolution. A procedure for analyzing the 3D-velocity field is presented that includes a method for accounting for vortex wander. The results show that a vortex generator can alter the trajectory of the trailing vortex and that a major change in the size and intensity of the trailing vortex can be achieved by introducing a high level of turbulence into the core of the vortex.

  9. Diagenetic alteration in low-Mg calcite from macrofossils

    DEFF Research Database (Denmark)

    Ullmann, Clemens Vinzenz; Korte, Christoph

    2015-01-01

    microscopy) and chemical (trace element abundances, isotopic ratios) screening techniques used to assess the alteration degree of low-Mg calcite macrofossils and summarize the findings on diagenetic trends observed for elemental and isotopic systems in such materials. For a robust evaluation...... of the preservation state of biogenic calcite, it is advisable to combine a set of complementary techniques. Absolute limiting values of element and isotope ratios for discarding diagenetically altered materials cannot be universally applied, but should rather be evaluated on a case to case basis. The evaluation can...

  10. Study on epigenetic alterations of ore-enclosing sedimentary rocks

    International Nuclear Information System (INIS)

    Kondrat'eva, I.A.; Komarova, G.V.

    1985-01-01

    Epigenetic alterations of sedimentary rocks under effect of exogenous undeground waters of various types: near-surface, ground, stratum, and deep circulation waters, are considered. Association to postsedimentary tectonic structures, confinement of neogenesis to areas of high permeability (porous or crack one), geochemical contradictions between mineral neogenis and facial outlook of deposits, noncoincidence of variability gradient of authigenous mineral associations with variability of primary facial signs of deposits, regular position of mineral formations and ore concentrations in epigenetic mineralogo-geochemical zonation are referred to epigenetic criteria. The complex of epigenetic alterations accompanying mineralization is frequently used as a search sign of uranium deposit of a certain type

  11. Altered inflammatory responsiveness in serotonin transporter mutant rats

    NARCIS (Netherlands)

    Macchi, F.; Homberg, J.R.; Calabrese, F.; Zecchillo, C.; Racagni, G.; Riva, M.A.; Molteni, R.

    2013-01-01

    BACKGROUND: Growing evidence suggests that alterations of the inflammatory/immune system contribute to the pathogenesis of depression. Indeed, depressed patients exhibit increased levels of inflammatory markers in both the periphery and the brain, and high comorbidity exists between major depression

  12. Altered biochemical specificity of G-quadruplexes with mutated tetrads

    Czech Academy of Sciences Publication Activity Database

    Švehlová, Kateřina; Lawrence, M. S.; Bednárová, Lucie; Curtis, Edward A.

    2016-01-01

    Roč. 44, č. 22 (2016), s. 10789-10803 ISSN 0305-1048 Institutional support: RVO:61388963 Keywords : G-quadruplex * G motif GTP aptamer * peroxidase deoxyribozyme Subject RIV: CE - Biochemistry Impact factor: 10.162, year: 2016 https://academic.oup.com/nar/article/44/22/10789/2333933/Altered-biochemical-specificity-of-G-quadruplexes

  13. Pharmacokinetic and pharmacodynamic alterations in older people with dementia.

    Science.gov (United States)

    Reeve, Emily; Trenaman, Shanna C; Rockwood, Kenneth; Hilmer, Sarah N

    2017-06-01

    The number of people with dementia internationally is increasing. Older adults with dementia are prescribed multiple medications, both to treat dementia symptoms and to manage their other medical conditions. Dementia is correlated with increasing age and frailty; this provides insight into how the efficacy and toxicity of medications may be altered in people with dementia. Areas covered: This review discusses the current evidence of the alterations in pharmacokinetics that can occur with aging, frailty and in people with dementia. The evidence is presented via the four primary pharmacokinetic processes (absorption, distribution, metabolism and elimination). Additionally, distribution into the brain, sex considerations and potential pharmacodynamic alterations in older people with dementia are discussed. Expert opinion: While the evidence is limited, people with dementia appear to be at a higher risk of toxicity of some medications due to altered pharmacokinetic processes and pharmacodynamics. There are a number of limitations to the research and there are still significant gaps in knowledge in this field. Proactive, ongoing review of the appropriateness of choice of medication, dose and whether or not a medication is required at all is necessary for achieving quality use of medications in people living with dementia.

  14. Bacterial vaginosis, alterations in vaginal flora and HIV genital ...

    African Journals Online (AJOL)

    Bacterial vaginosis, alterations in vaginal flora and HIV genital shedding among HIV-1-infected women in Mozambique. ... We compared women with detectable cervical HIV viral load (≥40 copies/ml) with women with undetectable cervical HIV. Results. We enrolled 106 women. Women with abnormal vaginal flora ...

  15. Does circumcision alter the periurethral uropathogenic bacterial flora

    African Journals Online (AJOL)

    Background: The aim of this study was to assess the pattern of periurethral bacterial flora in uncircumcised boys and to evaluate the effect of circumcision on alteration of periurethral uropathogenic bacterial flora. Materials and Methods: Pattern of periurethral bacterial flora before and after circumcision was studied ...

  16. Alterations in the morphology of skeletal myofibres after 90 minutes ...

    African Journals Online (AJOL)

    1991-03-16

    Mar 16, 1991 ... myelin figure (My) in intermyofibrillar space. The most obvious alteration in myofibre morphology follow- ing 90 minutes of tourniquet ischaemia was the substantial decrease in the amount of intermyofibrillar glycogen. This may be a natural consequence of anaerobic metabolism during the ischaemic period ...

  17. Alterations In Lipid Profile Of Patients With Advanced Cervical Cancer

    African Journals Online (AJOL)

    Background The changes in lipid profile have long been associated with cancer because lipids play key role in maintenance of cell integrity. Aims. The study evaluated alterations in plasma lipid profile in patients with advanced squamous cervical cancer. Materials And Method This hospital-based study included 30 cervical ...

  18. Functional network connectivity alterations in schizophrenia and depression.

    Science.gov (United States)

    Wu, Xing-Jie; Zeng, Ling-Li; Shen, Hui; Yuan, Lin; Qin, Jian; Zhang, Peng; Hu, Dewen

    2017-05-30

    There is a high degree of overlap between the symptoms of major depressive disorder (MDD) and schizophrenia, but it remains unclear whether the similar symptoms are derived from convergent alterations in functional network connectivity. In this study, we performed a group independent component analysis on resting-state functional MRI data from 20 MDD patients, 24 schizophrenia patients, and 43 matched healthy controls. The functional network connectivity analysis revealed that, compared to healthy controls, the MDD and schizophrenia patients exhibited convergent decreased positive connectivity between the left and right fronto-parietal control network and decreased negative connectivity between the left control and medial visual networks. Furthermore, the MDD patients showed decreased negative connectivity between the left control and auditory networks, and the schizophrenia patients showed decreased positive connectivity between the bilateral control and language networks and decreased negative connectivity between the right control and dorsal attention networks. The convergent network connectivity alterations may underlie the common primary control and regulation disorders, and the divergent connectivity alterations may enable the distinction between the two disorders. All of the convergent and divergent network connectivity alterations were relevant to the control network, suggesting an important role of the network in the pathophysiology of MDD and schizophrenia. Copyright © 2017. Published by Elsevier B.V.

  19. Chromium, Nickel and Zinc Induced Histopathological Alterations in ...

    African Journals Online (AJOL)

    Degenerative histopathalogical alterations were seen in liver due to chronic exposure of the fish, Labeo rohita to chlorides of chromium, nickel and zinc for 30 days. However, more severe degenerative changes were observed in case of zinc chloride exposed fish than nickel chloride and chromium chloride treated fishes, ...

  20. Chronic zinc deficiency alters chick gut microbiota composition and function

    Science.gov (United States)

    Zinc (Zn) deficiency is a prevalent micronutrient insufficiency. Although the gut is a vital organ for Zn utilization, and Zn deficiency is associated with impaired intestinal permeability and a global decrease in gastrointestinal health, alterations in the gut microbial ecology of the host under co...

  1. Alterations in the morphology of skeletal myofibres after 90 minutes ...

    African Journals Online (AJOL)

    Alterations in the morphology of skeletal myofibres after 90 minutes of ischaemia and '- 3 hours of reperfusion. M.A. Gregory, M. Mars. Abstract. Morphometric, light and electron microscopic methods were employed to determine whether skeletal myofibres were damaged by 90 minutes of tourniquet-mediated ischaemia.

  2. Neural Alterations in Acquired Age-Related Hearing Loss

    Science.gov (United States)

    Mudar, Raksha A.; Husain, Fatima T.

    2016-01-01

    Hearing loss is one of the most prevalent chronic health conditions in older adults. Growing evidence suggests that hearing loss is associated with reduced cognitive functioning and incident dementia. In this mini-review, we briefly examine literature on anatomical and functional alterations in the brains of adults with acquired age-associated hearing loss, which may underlie the cognitive consequences observed in this population, focusing on studies that have used structural and functional magnetic resonance imaging, diffusion tensor imaging, and event-related electroencephalography. We discuss structural and functional alterations observed in the temporal and frontal cortices and the limbic system. These neural alterations are discussed in the context of common cause, information-degradation, and sensory-deprivation hypotheses, and we suggest possible rehabilitation strategies. Although, we are beginning to learn more about changes in neural architecture and functionality related to age-associated hearing loss, much work remains to be done. Understanding the neural alterations will provide objective markers for early identification of neural consequences of age-associated hearing loss and for evaluating benefits of intervention approaches. PMID:27313556

  3. Chromium, Nickel and Zinc Induced Histopathological Alterations in ...

    African Journals Online (AJOL)

    Michael Horsfall

    ABSTRACT: Degenerative histopathalogical alterations were seen in liver due to chronic exposure of the fish, Labeo rohita to chlorides of chromium, nickel and zinc for 30 days. However, more severe degenerative changes were observed in case of zinc chloride exposed fish than nickel chloride and chromium chloride ...

  4. The landscape of genomic alterations across childhood cancers

    NARCIS (Netherlands)

    Gröbner, Susanne N.; Worst, Barbara C.; Weischenfeldt, Joachim; Buchhalter, Ivo; Kleinheinz, Kortine; Rudneva, Vasilisa A.; Johann, Pascal D.; Balasubramanian, Gnana Prakash; Segura-Wang, Maia; Brabetz, Sebastian; Bender, Sebastian; Hutter, Barbara; Sturm, Dominik; Pfaff, Elke; Hübschmann, Daniel; Zipprich, Gideon; Heinold, Michael; Eils, Jürgen; Lawerenz, Christian; Erkek, Serap; Lambo, Sander; Waszak, Sebastian; Blattmann, Claudia; Borkhardt, Arndt; Kuhlen, Michaela; Eggert, Angelika; Fulda, Simone; Gessler, Manfred; Wegert, Jenny; Kappler, Roland; Baumhoer, Daniel; Burdach, Stefan; Kirschner-Schwabe, Renate; Kontny, Udo; Kulozik, Andreas E.; Lohmann, Dietmar; Hettmer, Simone; Eckert, Cornelia; Bielack, Stefan; Nathrath, Michaela; Niemeyer, Charlotte; Richter, Günther H.; Schulte, Johannes; Siebert, Reiner; Westermann, Frank; Molenaar, Jan J.; Vassal, Gilles; Witt, Hendrik; Burkhardt, Birgit; Kratz, Christian P.; Witt, Olaf; van Tilburg, Cornelis M.; Kramm, Christof M.; Fleischhack, Gudrun; Dirksen, Uta; Rutkowski, Stefan; Frühwald, Michael; von Hoff, Katja; Wolf, Stephan; Klingebiel, Thomas; Koscielniak, Ewa; Landgraf, Pablo; Koster, Jan; Resnick, Adam C.; Zhang, Jinghui; Liu, Yanling; Zhou, Xin; Waanders, Angela J.; Zwijnenburg, Danny A.; Raman, Pichai; Brors, Benedikt; Weber, Ursula D.; Northcott, Paul A.; Pajtler, Kristian W.; Kool, Marcel; Piro, Rosario M.; Korbel, Jan O.; Schlesner, Matthias; Eils, Roland; Jones, David T. W.; Lichter, Peter; Chavez, Lukas; Zapatka, Marc; Pfister, Stefan M.; Weber, Ursula; Korshunov, Andrey; Pfister, Stefan; Reifenberger, Guido; Felsberg, Jörg; von Kalle, Christof; Schmidt, Manfred; Bartholomä, Cynthia; Taylor, Michael; Jones, David; Jäger, Natalie; Korbel, Jan; Stütz, Adrian; Rausch, Tobias; Radlwimmer, Bernhard; Yaspo, Marie-Laure; Lehrach, Hans; Warnatz, Hans-Jörg; Wagner, Susanne; Haake, Andrea; Richter, Julia; Richter, Gesine; Lawerenz, Chris; Kerssemakers, Jules; Jaeger-Schmidt, Christina; Scholz, Ingrid; Bergmann, Anke K.; Borst, Christoph; Claviez, Alexander; Dreyling, Martin; Eberth, Sonja; Einsele, Hermann; Frickhofen, Norbert; Haas, Siegfried; Hansmann, Martin-Leo; Karsch, Dennis; Kneba, Michael; Lisfeld, Jasmin; Mantovani-Löffler, Luisa; Rohde, Marius; Ott, German; Stadler, Christina; Staib, Peter; Stilgenbauer, Stephan; Trümper, Lorenz; Zenz, Thorsten; Kube, Dieter; Küppers, Ralf; Weniger, Marc; Hummel, Michael; Klapper, Wolfram; Kostezka, Ulrike; Lenze, Dido; Möller, Peter; Rosenwald, Andreas; Szczepanowski, Monika; Ammerpohl, Ole; Aukema, Sietse M.; Binder, Vera; Hoell, Jessica I.; Leich, Ellen; López, Cristina; Nagel, Inga; Pischimariov, Jordan; Rosenstiel, Philip; Schilhabel, Markus; Schreiber, Stefan; Vater, Inga; Wagener, Rabea; Bernhart, Stephan H.; Binder, Hans; Doose, Gero; Hoffmann, Steve; Hopp, Lydia; Kretzmer, Helene; Kreuz, Markus; Langenberger, David; Loeffler, Markus; Rosolowski, Maciej; Stadler, Peter F.; Sungalee, Stephanie

    2018-01-01

    Pan-cancer analyses that examine commonalities and differences among various cancer types have emerged as a powerful way to obtain novel insights into cancer biology. Here we present a comprehensive analysis of genetic alterations in a pan-cancer cohort including 961 tumours from children,

  5. Altered carbon dioxide metabolism and creatine abnormalities in rett syndrome

    NARCIS (Netherlands)

    Halbach, Nicky S J; Smeets, Eric E J; Bierau, Jörgen; Keularts, Irene M L W; Plasqui, Guy; Julu, Peter O O; Engerström, Ingegerd Witt; Bakker, Jaap A.; Curfs, Leopold M G

    2012-01-01

    Despite their good appetite, many females with Rett syndrome (RTT) meet the criteria for moderate to severe malnutrition. Although feeding difficulties may play a part in this, other constitutional factors such as altered metabolic processes are suspected. Irregular breathing is a common clinical

  6. Stuttering Inhibition via Altered Auditory Feedback during Scripted Telephone Conversations

    Science.gov (United States)

    Hudock, Daniel; Kalinowski, Joseph

    2014-01-01

    Background: Overt stuttering is inhibited by approximately 80% when people who stutter read aloud as they hear an altered form of their speech feedback to them. However, levels of stuttering inhibition vary from 60% to 100% depending on speaking situation and signal presentation. For example, binaural presentations of delayed auditory feedback…

  7. Effect of alteration phase formation on the glass dissolution rate

    Energy Technology Data Exchange (ETDEWEB)

    Ebert, W.L. [Argonne National Laboratory, Chemical Technology Div. (United States)

    1997-07-01

    The dissolution rates of many glasses have been observed to increase upon the formation of certain alteration phases. While simulations have predicted the accelerating effect of formation of certain phases, the phases predicted to form in computer simulations are usually different than those observed to form in experiments. This is because kinetically favored phases form first in experiments, while simulations predict the thermodynamically favored phases. Static dissolution tests with crushed glass have been used to measure the glass dissolution rate after alteration phases form. Because glass dissolution rates are calculated on a per area basis, an important effect in tests conducted with crushed glass is the decrease in the surface area of glass that is available for reaction as the glass dissolves. This loss of surface area must be taken into account when calculating the dissolution rate. The phases that form and their effect on the dissolution rate are probably related to the glass composition. The impact of phase formation on the glass dissolution rate also varies according to the solubility products of the alteration phases and how the orthocilicic acid activity is affected. Insight into the relationship between the glass dissolution rate, solution chemistry and alteration phase formation is provided by the results of accelerated dissolution tests.

  8. Altered mitochondrial regulation in quadriceps muscles of patients with COPD

    DEFF Research Database (Denmark)

    Naimi, Ashley I; Bourbeau, Jean; Perrault, Helene

    2011-01-01

    Evidence exists for locomotor muscle impairment in patients with chronic obstructive pulmonary disease (COPD), including fiber type alterations and reduced mitochondrial oxidative capacity. In this study high-resolution respirometry was used to quantify oxygen flux in permeabilized fibres from bi...

  9. IMMUNE AND NEUROIMMUNE ALTERATIONS IN MOOD DISORDERS AND SCHIZOPHRENIA

    NARCIS (Netherlands)

    Drexhage, Roosmarijn C.; Weigelt, Karin; van Beveren, Nico; Cohen, Dan; Versnell, Marjan A.; Nolen, Willem A.; Drexhage, Hemmo A.; Guest, PC; Bahn, S

    2011-01-01

    A large number of publications over the past 20 years have indicated that immune system function is altered in schizophrenia and mood disorder patients. This chapter reviews the evidence, which suggests that a proinflammatory state of the cytokine network induces psychopathologic symptoms and may be

  10. Neural Alterations in Acquired Age-Related Hearing Loss

    Directory of Open Access Journals (Sweden)

    Raksha Anand Mudar

    2016-06-01

    Full Text Available Hearing loss is one of the most prevalent chronic health conditions in older adults. Growing evidence suggests that hearing loss is associated with reduced cognitive functioning and incident dementia. In this mini-review, we briefly examine literature on anatomical and functional alterations in the brains of adults with acquired age-associated hearing loss, which may underlie the cognitive consequences observed in this population, focusing on studies that have used structural and functional magnetic resonance imaging, diffusion tensor imaging, and event-related electroencephalography. We discuss structural and functional alterations observed in the temporal and frontal cortices and the limbic system. These neural alterations are discussed in the context of common cause, information-degradation, and sensory-deprivation hypotheses, and we suggest possible rehabilitation strategies. Although we are beginning to learn more about changes in neural architecture and functionality related to age-associated hearing loss, much work remains to be done. Understanding the neural alterations will provide objective markers for early identification of neural consequences of age-associated hearing loss and for evaluating benefits of intervention approaches.

  11. A lumbar body support (KBS 2000) alters lumbar muscle recruitment ...

    African Journals Online (AJOL)

    back pain. K. L. Derman, E. w. Derman, T. D. Noakes. Objective. To determine the effects of a locally designed lumbar body support (LBS) on integrated ... surface, patients with chronic low back pain have higher. IEMG activity of the erector spinae ... It has also been shown that changes in sitting posture can alter LBP.6 The ...

  12. Mangrove expansion into salt marshes alters associated faunal communities

    Science.gov (United States)

    Delbert L. Smee; James A. Sanchez; Meredith Diskin; Carl Trettin

    2017-01-01

    Climate change is altering the distribution of foundation species, with potential effects on organisms that inhabit these environments and changes to valuable ecosystem functions. In the Gulf of Mexico, black mangroves (Avicennia germinans) are expanding northward into salt marshes dominated by Spartina alterniflora (hereafter Spartina). Salt marshes are essential...

  13. Antibiotic use during pregnancy alters the commensal vaginal microbiota

    DEFF Research Database (Denmark)

    Stokholm, J.; Schjørring, S.; Eskildsen, Carl Emil Aae

    2014-01-01

    Antibiotics may induce alterations in the commensal microbiota of the birth canal in pregnant women. Therefore, we studied the effect of antibiotic administration during pregnancy on commensal vaginal bacterial colonization at gestational week 36. Six hundred and sixty-eight pregnant women from...

  14. Alteration of basaltic glasses from the Central Indian Ocean

    Digital Repository Service at National Institute of Oceanography (India)

    Iyer, S.D.

    chemical changes are the loss of Si, Mg and Ca and a gain of Na and K whilst, Fe and Ti remained immobile. It reflects that the basaltic glasses have undergone initial to intermediate stages of palagonitisation under low temperature oxidative alterations...

  15. Altered Resting Brain Function and Structure in Professional Badminton Players

    Science.gov (United States)

    Di, Xin; Zhu, Senhua; Wang, Pin; Ye, Zhuoer; Zhou, Ke; Zhuo, Yan

    2012-01-01

    Abstract Neuroimaging studies of professional athletic or musical training have demonstrated considerable practice-dependent plasticity in various brain structures, which may reflect distinct training demands. In the present study, structural and functional brain alterations were examined in professional badminton players and compared with healthy controls using magnetic resonance imaging (MRI) and resting-state functional MRI. Gray matter concentration (GMC) was assessed using voxel-based morphometry (VBM), and resting-brain functions were measured by amplitude of low-frequency fluctuation (ALFF) and seed-based functional connectivity. Results showed that the athlete group had greater GMC and ALFF in the right and medial cerebellar regions, respectively. The athlete group also demonstrated smaller ALFF in the left superior parietal lobule and altered functional connectivity between the left superior parietal and frontal regions. These findings indicate that badminton expertise is associated with not only plastic structural changes in terms of enlarged gray matter density in the cerebellum, but also functional alterations in fronto-parietal connectivity. Such structural and functional alterations may reflect specific experiences of badminton training and practice, including high-capacity visuo-spatial processing and hand-eye coordination in addition to refined motor skills. PMID:22840241

  16. Listeria monocytogenes transiently alters mitochondrial dynamics during infection

    OpenAIRE

    Stavru, Fabrizia; Bouillaud, Frederic; Sartori, Anna; Ricquier, Daniel; Cossart, Pascale

    2011-01-01

    Mitochondria are essential and highly dynamic organelles, constantly undergoing fusion and fission. We analyzed mitochondrial dynamics during infection with the human bacterial pathogen Listeria monocytogenes and show that this infection profoundly alters mitochondrial dynamics by causing transient mitochondrial network fragmentation. Mitochondrial fragmentation is specific to pathogenic Listeria monocytogenes, and it is not observed with the nonpathogenic Listeria innocua species or several ...

  17. Petrography of some altered intrusive rocks from the Lower Benue ...

    African Journals Online (AJOL)

    Petrography of some altered intrusive rocks from the Lower Benue Trough, Nigeria. Smart C Obiora, Alphonso C Umeji. Abstract. No Abstract. Journal of Mining and Geology 2005, Vol 41(1): 1-9. Full Text: EMAIL FULL TEXT EMAIL FULL TEXT · DOWNLOAD FULL TEXT DOWNLOAD FULL TEXT.

  18. Haemodialysis and peritoneal dialysis: metabolic alterations and nutritional status.

    Science.gov (United States)

    Cano, N

    1999-07-01

    In dialysis patients, malnutrition is an independent factor causing morbidity and mortality. Both inadequate alimentation and metabolic alterations, which involve nitrogen and energy metabolism, contribute to malnutrition. Future research must address the treatment of anorexia and inflammation-induced catabolism, as well as the evaluation of nutritional supplementation techniques and anabolic drugs.

  19. Efficacy of lower doses of vanadium in restoring altered glucose ...

    Indian Academy of Sciences (India)

    Unknown

    Insulin restored the levels of altered enzyme acti- vities and metabolites almost to control levels. Sodium orthovanadate (0⋅6 mg/ml) and Trigonella administered separately to diabetic animals could partially reverse the diabetic changes, metabolic and morphological, while vanadate in lowered dose in combination with ...

  20. Attention alters orientation processing in the human lateral geniculate nucleus.

    Science.gov (United States)

    Ling, Sam; Pratte, Michael S; Tong, Frank

    2015-04-01

    Orientation selectivity is a cornerstone property of vision, commonly believed to emerge in the primary visual cortex. We found that reliable orientation information could be detected even earlier, in the human lateral geniculate nucleus, and that attentional feedback selectively altered these orientation responses. This attentional modulation may allow the visual system to modify incoming feature-specific signals at the earliest possible processing site.

  1. Antagonist effects of calcium on borosilicate glass alteration

    Science.gov (United States)

    Mercado-Depierre, S.; Angeli, F.; Frizon, F.; Gin, S.

    2013-10-01

    Numerous studies have been conducted on glass and cement durability in contact with water, but very little work to date has focused directly on interactions between the two materials. These interactions are mostly controlled by silicon-calcium reactivity. However, the physical and chemical processes involved remain insufficiently understood to predict the evolution of coupled glass-cement systems used in several industrial applications. Results are reported from borosilicate glass alteration in calcium-rich solutions. Our data show that four distinct behaviors can be expected according to the relative importance of three key parameters: the pH, the reaction progress (short- or long-term alteration) and the calcium concentration. Glass alteration is thus controlled by specific mechanisms depending on the solution chemistry: calcium complexation at the glass surface, precipitation of calcium silicate hydrates (C-S-H) or calcium incorporation in the altered layer. These findings highlight the impact of silicon-calcium interactions on glass durability and open the way for a better understanding of glass-cement mixing in civil engineering applications as well as in nuclear waste storage.

  2. Altered Eating Behaviors in Female Victims of Intimate Partner Violence.

    Science.gov (United States)

    Wong, Susan P Y; Chang, Judy C

    2016-12-01

    Little is known about altered eating behaviors that are associated with the experience of intimate partner violence (IPV) victimization. Our aim was to explore the experiences and perspectives of IPV victims regarding their eating behaviors and their attitudes toward and use of food. We conducted focus groups and individual interviews with 25 IPV victims identified at a domestic violence agency and asked them about their eating behaviors and how, if at all, these behaviors related to their experience of IPV. Qualitative analysis of the transcribed encounters identified themes explicating the relationship between their eating behaviors and experiences of IPV. All women described altered eating behaviors related to IPV that were categorized into several major themes: (a) somatization (victims experience significant somatic symptoms as a result of abuse); (b) avoiding abuse (victims modify their eating behaviors to avoid abuse); (c) coping (victims use food to handle the psychological effects of abuse); (d) self-harm (victims use food to hurt themselves as a reaction to the abuse); and (e) challenging abusive partners (victims use their eating behaviors to retaliate against their abusers). IPV can provoke altered eating behaviors in victims that may be harmful, comforting, or a source of strength in their abusive relationships. Understanding the complex relationship between IPV and victims' altered eating behaviors is important in promoting healthy eating among victims. © The Author(s) 2015.

  3. Electromagnetic Evidence of Altered Visual Processing in Autism

    Science.gov (United States)

    Neumann, Nicola; Dubischar-Krivec, Anna M.; Poustka, Fritz; Birbaumer, Niels; Bolte, Sven; Braun, Christoph

    2011-01-01

    Individuals with autism spectrum disorder (ASD) demonstrate intact or superior local processing of visual-spatial tasks. We investigated the hypothesis that in a disembedding task, autistic individuals exhibit a more local processing style than controls, which is reflected by altered electromagnetic brain activity in response to embedded stimuli…

  4. Histological and histochemical alterations in the kidney induced by lead

    International Nuclear Information System (INIS)

    Jarrar, Bashir M.

    2003-01-01

    Although lead intoxication is one of the most common forms of metal intoxication,the histochemichal alterations in renal tissues due to chronic lead exposure is limited and has not yet been well identified. A total of 60 male Wistar albino rats were exposed to lead acetate trihydrate( 0.0, 0.25, 0.5, 1.0 and 2% for 1 to 12 months) in drinking water to investigate the histological and histochemical alterations in renal tissues due to lead. Chronic exposure to the subtoxic doses of lead produced distinct progressive tubular, glomerular and interstitial damages. Tubular changes occured earlier than the glomerular and interstitial ones,and included anisokaryosis, nuclear pyknosis,karyomeglay, development of intranuclear cytoplasmic inclusions together with tubular dilation, necrosis,vacuolization, tubular hyperplasia and solid tubular adenoma. The glomrular alterations were mainly mesangial hypercellularity, segmental glomerulosclerosis, glomerular hyalinization and glomerular tuft alterations. The findings indicate that lead produces significant histological and histochemical changes in the kidney that lead to severe complications. (author)

  5. Functional lymphatic alterations in patients suffering from lipedema.

    Science.gov (United States)

    Bilancini, S; Lucchi, M; Tucci, S; Eleuteri, P

    1995-04-01

    Lipedema is a chronic vascular disease almost exclusively of female sex, characterized by the deposit of fat on the legs, with an "Egyptian column" shape, orthostatic edema, hypothermia of the skin, alteration of the plantar support, and negativity of Stemmer's sign. The etiology and pathogenesis of this disease are still the object of study, and therapy is very difficult. Various authors have described morphologic and functional alterations of prelymphatic structures and of lymphatic vessels. The big veins remain untouched in the phlebograms and an alteration of the skin elasticity is demonstrated. The present authors have studied by dynamic lymphoscintigraphy 12 women patients suffering from lipedema, and compared the results with those of 5 normal subjects and 5 patients suffering from idiopathic lymphedema who were sex and age matched with the patients suffering from lipedema. The patients suffering from lipedema showed an abnormal lymphoscintigraphic pattern with a slowing of the lymphatic flow that presented some analogies to the alterations found in the patients suffering from lymphedema. A frequent asymmetry was also noticed in the lymphoscintigraphic findings that is in contrast to the symmetry of the clinical profile.

  6. Connectomics and neuroticism : an altered functional network organization

    NARCIS (Netherlands)

    Servaas, Michelle N; Geerligs, Linda; Renken, Remco J; Marsman, Jan-Bernard; Ormel, Johan; Riese, Harriëtte; Aleman, André

    The personality trait neuroticism is a potent risk marker for psychopathology. Although the neurobiological basis remains unclear, studies have suggested that alterations in connectivity may underlie it. Therefore, the aim of the current study was to shed more light on the functional network

  7. Pollutant Induced Altered Behaviours in Fish: A Review of Selected ...

    African Journals Online (AJOL)

    Pollutant Induced Altered Behaviours in Fish: A Review of Selected Literature. UU Gabriel, B Uedeme-Naa, OA Akinrotimi. Abstract. The issue of environmental pollution has become a global phenomenon in recent years, of importance is the aquatic environment, which acts as a sink for these contaminants which pose ...

  8. Warming can boost denitrification disproportionately due to altered oxygen dynamics

    NARCIS (Netherlands)

    Veraart, A.J.; Klein, de J.J.M.; Scheffer, M.

    2011-01-01

    Background - Global warming and the alteration of the global nitrogen cycle are major anthropogenic threats to the environment. Denitrification, the biological conversion of nitrate to gaseous nitrogen, removes a substantial fraction of the nitrogen from aquatic ecosystems, and can therefore help to

  9. Alterations in reducing sugar in Triticum aestivum under irrigated ...

    African Journals Online (AJOL)

    This research was conducted with the objective of observing alterations in reducing sugars, which may play a part in distinguishing tolerant and susceptible genotypes. The experimental material consisted of thirteen wheat genotypes including eleven bread wheat advanced lines, one synthetic hexaploid and its durum ...

  10. Phytochemicals Perturb Membranes and Promiscuously Alter Protein Function

    NARCIS (Netherlands)

    Ingólfsson, Helgi I; Thakur, Pratima; Herold, Karl F; Hobart, E Ashley; Ramsey, Nicole B; Periole, Xavier; de Jong, Djurre H; Zwama, Martijn; Yilmaz, Duygu; Hall, Katherine; Maretzky, Thorsten; Hemmings, Hugh C; Blobel, Carl; Marrink, Siewert J; Kocer, Armagan; Sack, Jon T; Andersen, Olaf S

    A wide variety of phytochemicals are consumed for their perceived health benefits. Many of these phytochemicals have been found to alter numerous cell functions, but the mechanisms underlying their biological activity tend to be poorly understood. Phenolic phytochemicals are particularly promiscuous

  11. Molecular alterations of parotid saliva in infantile chronic recurrent parotitis.

    Science.gov (United States)

    Morales-Bozo, Irene; Urzúa-Orellana, Blanca; Landaeta, Mirtha; Montalbán, Raúl; Torres, Jimena; Pinochet, Alvaro; Valverde, Gustavo; Muñoz-Martínez, Andrea

    2007-02-01

    Infantile chronic recurrent parotitis (ICRP) is an insidious disease whose etiopathogenesis remains an enigma. Alterations in the physical appearance of parotid saliva from ICRP patients have been frequently reported. However, sialochemical studies in regard to ICRP are very rare. The aim of this study was to determine whether saliva of ICRP patients presents major physicochemical and biochemical alterations compared with saliva from paired healthy controls. Parotid, whole, and submandibular/sublingual saliva was collected at an asymptomatic stage from 33 ICRP patients (5-16 y old, both sexes) and from 33 sex- and age-matched healthy controls. Saliva was analyzed for protein concentration, mode of protein diffusion on cellulose membranes, unidimensional sodium dodecylsulfate (SDS)-polyacrylamide gel electrophoresis protein profiles and zymographic profiles of metalloproteinase 2 (MMP-2) and metalloproteinase 9 (MMP-9). Parotid saliva of ICRP patients showed an increased protein concentration, altered mode of protein diffusion, a higher frequency of polypeptide bands of 43, 37, 33, 29, 26, 16, and 10 kD, higher asymmetry in the polypeptide profiles of both contralateral parotid saliva, and an increase in the frequency of MMP-2 and MMP-9. Parotid saliva of patients with ICRP is molecularly altered with respect to normal saliva. Some of the molecular differences could be related to the etiopathogenesis of the disease.

  12. Altered erythropoiesis and iron metabolism in carriers of thalassemia

    Science.gov (United States)

    Guimarães, Jacqueline S.; Cominal, Juçara G.; Silva-Pinto, Ana Cristina; Olbina, Gordana; Ginzburg, Yelena Z.; Nandi, Vijay; Westerman, Mark; Rivella, Stefano; de Souza, Ana Maria

    2014-01-01

    The thalassemia syndromes (α- and β-thalassemia) are the most common and frequent disorders associated with ineffective erythropoiesis. Imbalance of α- or β-globin chain production results in impaired red blood cell synthesis, anemia and more erythroid progenitors in the blood stream. While patients affected by these disorders show definitive altered parameters related to erythropoiesis, the relationship between the degree of anemia, altered erythropoiesis and dysfunctional iron metabolism have not been investigated in both α-thalassemia carriers (ATC) and β-thalassemia carriers (BTC). Here we demonstrate that ATC have a significantly reduced hepcidin and increased soluble transferrin receptor levels but relatively normal hematological findings. In contrast, BTC have several hematological parameters significantly different from controls, including increased soluble transferrin receptor and erythropoietin levels. These changings in both groups suggest an altered balance between erythropoiesis and iron metabolism. The index sTfR/log ferrin and (hepcidin/ferritin)/sTfR are respectively increased and reduced relative to controls, proportional to the severity of each thalassemia group. In conclusion, we showed in this study, for the first time in the literature, that thalassemia carriers have altered iron metabolism and erythropoiesis. PMID:25307880

  13. Tumor microenvironmental genomic alterations in juvenile nasopharyngeal angiofibroma

    DEFF Research Database (Denmark)

    Silveira, Sara Martoreli; Custódio Domingues, Maria Aparecida; Butugan, Ossamu

    2012-01-01

    % of chromosomal alterations were common by both components. Gene expression analyses revealed a positive correlation between endothelial and stromal components for ASPM, CDH1, CTNNB1, FGF18, and SUPT16H. A significant difference was found for FGF18 and AURKB overexpression in stromal cells and AR down...

  14. Altered extracellular magnesium and variations in vascular smooth ...

    African Journals Online (AJOL)

    Altered extracellular magnesium and variations in vascular smooth muscle responses to agonists. ... (5-HT) were examined on 2mm ring segments of the arteries which were suspended in 20 ml organ baths containing physiological salt solution (PSS), for measurement of isometric contractions, at 37oC and pH 7.4.

  15. Arts Practice and Research: Locating Alterity and Expertise

    Science.gov (United States)

    Grennan, Simon

    2015-01-01

    There is still no agreed pedagogic definition of practice-based research. However, there is not a dearth of definitions, but rather a wide variety, predicated upon the developing programmes of individual places of study. This article will examine these definitions in terms of underlying concepts of intentionality and alterity and the ways in which…

  16. Altered sense of agency in children with spastic cerebral palsy

    DEFF Research Database (Denmark)

    Ritterband-Rosenbaum, Anina; Christensen, Mark S; Kliim-Due, Mette

    2011-01-01

    ABSTRACT: Background Children diagnosed with spastic Cerebral Palsy (CP) often show perceptual and cognitive problems, which may contribute to their functional deficit. Here we investigated if altered ability to determine whether an observed movement is performed by themselves (sense of agency...

  17. Natural alteration products of sulphide mattes from primary lead smelting

    Czech Academy of Sciences Publication Activity Database

    Ettler, V.; Johan, Z.; Hradil, David

    2003-01-01

    Roč. 335, č. 14 (2003), s. 1013-1020 ISSN 1631-0713 R&D Projects: GA MŠk LN00A028; GA ČR GP205/01/D132 Institutional research plan: CEZ:AV0Z4032918 Keywords : matte * lead smelting * alteration Subject RIV: CA - Inorganic Chemistry Impact factor: 0.366, year: 2003

  18. 49 CFR 230.34 - Riveted repairs and alterations.

    Science.gov (United States)

    2010-10-01

    ... satisfy reporting requirements in § 230.20 at this time. Pressure Testing of Boilers ... ADMINISTRATION, DEPARTMENT OF TRANSPORTATION STEAM LOCOMOTIVE INSPECTION AND MAINTENANCE STANDARDS Boilers and... portions of the boiler. Prior to making riveted alterations on unstayed portions of the boiler, the steam...

  19. Altered Endothelium-Dependent Vasoreactivity of Aortic Rings ...

    African Journals Online (AJOL)

    Purpose: The use of L-arginine and potassium chloride separately as supplements has been reported to result in altered vascular reactivity. The concentration of either agent used has varied widely and there has been no report on the outcome of combined supplementation with both agents on vascular reactivity.

  20. How liana loads alter tree allometry in tropical forests

    NARCIS (Netherlands)

    Souza Dias, de Arildo; Santos, Dos Karin; Santos, Dos Flavio Antonio Maës; Martins, Fernando R.

    2017-01-01

    Intense competition with lianas (wood climbers) can limit tree growth, reproduction, and survival. However, the negative effects of liana loads on tree allometry have not yet been addressed. We investigated the hypothesis that liana loading on tree crown alters tree’s allometry, expressed through

  1. Alterations of blood indices associated with low-dose administration ...

    African Journals Online (AJOL)

    The study aimed to investigate haematological and biochemical alterations associated with short-term intraperitoneal sublethal (1/10 LD50, 2 mg/kg body weight) methomyl administration to male albino rats over two and five days, and also the effects of a two-week recovery period. Methomyl administration over five but not ...

  2. Restraint stress impairs glucose homeostasis through altered insulin ...

    African Journals Online (AJOL)

    The study investigated the potential alteration in the level of insulin and adiponectin, as well as the expression of insulin receptors (INSR) and glucose transporter 4 GLUT-4 in chronic restraint stress rats. Sprague-Dawley rats were randomly divided into two groups: the control group and stress group in which the rats were ...

  3. Structural Alterations of the Glomerular Wall And Vessels in Early ...

    African Journals Online (AJOL)

    Structural Alterations of the Glomerular Wall And Vessels in Early Stages of Diabetes Mellitus: Light and Transmission Electron Microscopic Study. ... The second group of 20 (the experimental group) was injected intraperitoneally by a single dose of streptozotocin to induce hyperglycemia. Rats were sacrificed after ten days, ...

  4. Colonoscopic evaluation of middle aged patients with altered bowel habits

    International Nuclear Information System (INIS)

    Bhatti, M.A.; Kashif, M.A.; Imran, M.

    2004-01-01

    Objective: To determine the frequency of colorectal carcinoma in-patients above 40 years of age presenting with altered bowel habits by colonoscopy. Patients and Methods: A group of 50 consecutive cases presenting with altered bowel habits meeting the inclusion and exclusion criteria were included in the study. History and physical examination were recorded on a specifically designed proforma. Colonoscopy was done in these patients and any abnormality found was reported and biopsy specimen taken and sent for histopathology. Results: A total number of 17 patients presenting with altered bowel habits were found to be suffering from colorectal carcinoma by colonoscopy. Among these in 30% the lesion was in the rectum , in 9% the lesion was in the sigmoid colon, 6% in the descending colon, 4% at the splenic flexure, 5% in the transverse colon, in 16% the lesion was found at the hepatic flexure and in 30% the lesion was in the ascending colon and caecum. Conclusion: Frequency of colorectal carcinoma is high in-patients above 40 years of age who presenting with altered bowel habits. They should be investigated preferably by means of colonoscopy which is the most complete method of investigation and diagnostic procedure of choice in patients with a clinical suspicion of colorectal carcinoma.(author)

  5. Altered Amygdala Development and Fear Processing in Prematurely Born Infants.

    Science.gov (United States)

    Cismaru, Anca Liliana; Gui, Laura; Vasung, Lana; Lejeune, Fleur; Barisnikov, Koviljka; Truttmann, Anita; Borradori Tolsa, Cristina; Hüppi, Petra S

    2016-01-01

    Prematurely born children have a high risk of developmental and behavioral disabilities. Cerebral abnormalities at term age have been clearly linked with later behavior alterations, but existing studies did not focus on the amygdala. Moreover, studies of early amygdala development after premature birth in humans are scarce. To compare amygdala volumes in very preterm infants at term equivalent age (TEA) and term born infants, and to relate premature infants' amygdala volumes with their performance on the Laboratory Temperament Assessment Battery (Lab-TAB) fear episode at 12 months. Eighty one infants born between 2008 and 2014 at the University Hospitals of Geneva and Lausanne, taking part in longitudinal and functional imaging studies, who had undergone a magnetic resonance imaging (MRI) scan at TEA enabling manual amygdala delineation. Amygdala volumes assessed by manual segmentation of MRI scans; volumes of cortical and subcortical gray matter, white matter and cerebrospinal fluid (CSF) automatically segmented in 66 infants; scores for the Lab-TAB fear episode for 42 premature infants at 12 months. Amygdala volumes were smaller in preterm infants at TEA than term infants (mean difference 138.03 mm(3), p motor activity in the fear episode. Our results indicate that premature birth is associated with a reduction in amygdala volumes and white matter volumes at TEA, suggesting that altered amygdala development might be linked to alterations in white matter connectivity reported in premature infants. Moreover, our data suggests that such alterations might affect infants' fear-processing capabilities.

  6. Alterations in reducing sugar in Triticum aestivum under irrigated ...

    African Journals Online (AJOL)

    DELL

    2012-03-13

    Mar 13, 2012 ... This research was conducted with the objective of observing alterations in reducing sugars, which may play a part in distinguishing tolerant and susceptible genotypes. The experimental material consisted of thirteen wheat genotypes including eleven bread wheat advanced lines, one synthetic hexaploid ...

  7. Pinyon pine mortality alters communities of ground-dwelling arthropods

    Science.gov (United States)

    Robert J. Delph; Michael J. Clifford; Neil S. Cobb; Paulette L. Ford; Sandra L. Brantley

    2014-01-01

    We documented the effect of drought-induced mortality of pinyon pine (Pinus edulis Engelm.) on communities of ground-dwelling arthropods. Tree mortality alters microhabitats utilized by ground-dwelling arthropods by increasing solar radiation, dead woody debris, and understory vegetation. Our major objectives were to determine (1) whether there were changes in...

  8. Effect of composition variations on the long-term wasteform behavior of vitrified domestic waste incineration fly-ash purification residues; Influence des variations de composition des vitrifiats de refiom - residus d'epuration des fumees d'incineration d'ordures menageres - sur leur comportement a long terme

    Energy Technology Data Exchange (ETDEWEB)

    Frugier, P.

    2000-07-01

    The effect of variations in the composition of fly-ash purification residue from incinerated domestic waste on the quality of the containment achieved by vitrification was investigated. Three main factors determine the long-term containment quality: the production of a vitrified wasteform, the occurrence of possible crystallization, and the key parameters of long-term alteration in aqueous media. Each of these aspects is described within a composition range defined by variations in the three major elements. (silicon, calcium and aluminum) and two groups of constituents (alkali metals and toxic elements). The silicon fraction in the fly-ash residue was found to be decisive: it is impossible to obtain a satisfactory vitrified wasteform below a given silicon concentration. Compounds with the lowest silica content also exhibited the greatest tendency to crystallize under the cooling conditions prevailing in industrial processes (the dominant crystallized phase is a melilite that occupies a significant fraction of the material and considerably modifies the alteration mechanisms). The initial alteration rate in pure water and the altered glass thickness measured in a closed system at an advanced stage of the dissolution reaction are both inversely related to the silicon concentration in the glass. Several types of long-term behavior were identified according to the composition range, the process conditions and the vitrified waste disposal scenario. Four distinct 'classes' of vitrified wasteform were defined for direct application in industrial processes. (author)

  9. Cryptic Carbonate Alteration in Orogenic Sedimentary Basins: Saving the Signal

    Science.gov (United States)

    Ingalls, M.; Rowley, D. B.; Colman, A. S.; Currie, B.; Snell, K. E.

    2017-12-01

    The clumped isotope thermometer (T(Δ47)) is arguably one of the most important tools introduced to the fields of paleoclimatology and tectonics in the past decade. However, we measure clumped isotope abundances in natural materials collected from sedimentary basins, many of which have experienced complex thermal and fluid interaction histories. Throughout the history of an authigenic mineral—from precipitation to exhumation—there are multiple opportunities to overprint isotopic signatures and obscure the essential fingerprint of primary environmental conditions. Therefore, we must critically assess the presence or absence of textural and isotopic alteration after original mineral formation. We investigate Paleocene shallow marine carbonates from the Xigaze forearc (S. Tibet) that yield demonstrably non-marine δ18Oc values (-12 to -21‰ VPDB), significant cm-scale variation in clumped isotope values (0.456 to 0.721‰, or 80 to 20°C), and have experienced temperatures >150°C for longer than 10 My based on ages of partial resetting of zircon He. δ18Oc values require complete oxygen isotopic exchange during fluid-buffered diagenesis, but display little visible evidence of recrystallization. Further, within the constraints of the Xigaze forearc time-temperature history, we explain the intrasample Δ47 variation by a combination of the two known mechanisms of Δ47 alteration: (1) water-rock recrystallization and (2) solid-state reordering. The definitively altered marine carbonates pass the same optical screening tests for secondary mineralization traditionally used when employing δ18Oc or Δ47 as proxies for ancient Earth conditions, suggesting that alteration occurred on a spatial scale irresolvable by standard techniques. Therefore, higher spatial resolution detection of carbonate alteration is required to prevent incorrect or incomplete interpretation of carbonate isotopic values. We employ a suite of isotopic (δ18O, δ13C, Δ47, U/Pb), geochemical (EBSD

  10. The alteration of intracellular enzymes. III. The effect of temperature on the kinetics of altered and unaltered yeast catalase.

    Science.gov (United States)

    FRASER, M J; KAPLAN, J G

    1955-03-20

    1. The very large increase in catalase activity (Euler effect) which follows treatment of yeast cells with CHCl(3), UV and n-propanol is accompanied by highly significant changes in kinetic properties. With respect to the enzymatic decomposition of H(2)O(2), the thermodynamic constants of the activation process micro, DeltaHdouble dagger, DeltaSdouble dagger, DeltaFdouble dagger, decrease, following treatment of the intracellular enzyme, by 4.5 kcal., 4.5 kcal., 10.1 e.u. and 1.7 kcal., respectively, all these differences being significant at the 1 per cent level. 2. Similar differences exist between the untreated, intracellular enzyme on the one hand, and the extracted yeast and crystalline beef liver catalases on the other. Significant differences in these thermodynamic constants do not exist among the treated intracellular, extracted yeast, and crystalline liver catalases. 3. These data provide unequivocal confirmation of the phenomenon of enzyme alteration reported previously, and confirm previous evidence that the extracted and crystalline enzymes have also undergone enzyme alteration and have properties which are identical with, or very similar to, those of the catalase altered in situ. 4. With respect to the process of heat destruction of catalase, the greatly diminished stability to heat of the altered enzymes, previously reported, has been confirmed. The thermodynamic constants of activation of this process have likewise changed following alteration, in the case of micro, DeltaHdouble dagger, and DeltaSdouble dagger an increase of 20.6 kcal., 20.6 kcal., and 70 e.u., respectively, and of DeltaFdouble dagger a decrease of 2.8 kcal. 5. All these data have been shown to be consistent with, and in some cases predictable from, the interfacial hypothesis, which states that the unaltered catalase exists within the cell adsorbed to some interface, in a partially, but reversibly, unfolded configuration of relatively low specificity; enzyme alteration consists, in

  11. Caffeine exposure alters cardiac gene expression in embryonic cardiomyocytes

    Science.gov (United States)

    Fang, Xiefan; Mei, Wenbin; Barbazuk, William B.; Rivkees, Scott A.

    2014-01-01

    Previous studies demonstrated that in utero caffeine treatment at embryonic day (E) 8.5 alters DNA methylation patterns, gene expression, and cardiac function in adult mice. To provide insight into the mechanisms, we examined cardiac gene and microRNA (miRNA) expression in cardiomyocytes shortly after exposure to physiologically relevant doses of caffeine. In HL-1 and primary embryonic cardiomyocytes, caffeine treatment for 48 h significantly altered the expression of cardiac structural genes (Myh6, Myh7, Myh7b, Tnni3), hormonal genes (Anp and BnP), cardiac transcription factors (Gata4, Mef2c, Mef2d, Nfatc1), and microRNAs (miRNAs; miR208a, miR208b, miR499). In addition, expressions of these genes were significantly altered in embryonic hearts exposed to in utero caffeine. For in utero experiments, pregnant CD-1 dams were treated with 20–60 mg/kg of caffeine, which resulted in maternal circulation levels of 37.3–65.3 μM 2 h after treatment. RNA sequencing was performed on embryonic ventricles treated with vehicle or 20 mg/kg of caffeine daily from E6.5-9.5. Differential expression (DE) analysis revealed that 124 genes and 849 transcripts were significantly altered, and differential exon usage (DEU) analysis identified 597 exons that were changed in response to prenatal caffeine exposure. Among the DE genes identified by RNA sequencing were several cardiac structural genes and genes that control DNA methylation and histone modification. Pathway analysis revealed that pathways related to cardiovascular development and diseases were significantly affected by caffeine. In addition, global cardiac DNA methylation was reduced in caffeine-treated cardiomyocytes. Collectively, these data demonstrate that caffeine exposure alters gene expression and DNA methylation in embryonic cardiomyocytes. PMID:25354728

  12. Assessment of climate variability and hydrological alterations in Kaidu Basin

    Science.gov (United States)

    Shen, Yan-Jun; Shen, Yanjun; Fink, Manfred; Kralisch, Sven; Brenning, Alexander

    2017-04-01

    Climate change and hydrological alterations are major concerns in a mountain river ecosystem. We provide an essential assessment of climate variability (1961-2011) in Kaidu basin by means of Mann-Kendall test and cumulative anomalies. The Indicator of Hydrologic Alteration (IHA) was further performed to analyze hydrological alterations (1972-2008). Change in the triggering of snowmelt runoff timing was analyzed by the winter/spring snowmelt runoff center time (WSCT). Results reveal that annual precipitation and temperature show an increase tendency, but with a significant trend in winter and summer, respectively, while the discharge reveals significant rises in both annual and seasonal scales. However, all the hydro-meteorological parameters show an obvious increase tendency especially in the mid-1990s. WSCT has a significant decreasing trend and was observed earlier by nearly 10 days in Kaidu Basin. Higher relationship between WSCT with temperatures (March to April, R= - 0.51) and precipitation (February to March, R=0.33) were found that temperature may play a major role in causing the earlier WSCT. Account for the reservoirs influences, the rise rate and monthly flows have increased evidently before and after the reservoirs regulation. Monthly streamflow was found higher in pre-impact (1972-1992) than post-impact period (1993-2008) based on the flow duration curves. Nevertheless, the base flow index displayed no change before and after the impact period. Consequently, both of climate change and reservoir regulation lead to a concentrated streamflow. Research should take this influence into consideration in hydrological analysis and modelling in terms of uncertainties. These findings deepen our understanding of climate change and hydrological alterations in Kaidu basin, and are useful for flood risk regulation, ecological restoration and future hydropower plants. Keywords: Climate change; Spring snowmelt runoff time; WSCT; hydrological alterations; IHA

  13. Caffeine exposure alters cardiac gene expression in embryonic cardiomyocytes.

    Science.gov (United States)

    Fang, Xiefan; Mei, Wenbin; Barbazuk, William B; Rivkees, Scott A; Wendler, Christopher C

    2014-12-15

    Previous studies demonstrated that in utero caffeine treatment at embryonic day (E) 8.5 alters DNA methylation patterns, gene expression, and cardiac function in adult mice. To provide insight into the mechanisms, we examined cardiac gene and microRNA (miRNA) expression in cardiomyocytes shortly after exposure to physiologically relevant doses of caffeine. In HL-1 and primary embryonic cardiomyocytes, caffeine treatment for 48 h significantly altered the expression of cardiac structural genes (Myh6, Myh7, Myh7b, Tnni3), hormonal genes (Anp and BnP), cardiac transcription factors (Gata4, Mef2c, Mef2d, Nfatc1), and microRNAs (miRNAs; miR208a, miR208b, miR499). In addition, expressions of these genes were significantly altered in embryonic hearts exposed to in utero caffeine. For in utero experiments, pregnant CD-1 dams were treated with 20-60 mg/kg of caffeine, which resulted in maternal circulation levels of 37.3-65.3 μM 2 h after treatment. RNA sequencing was performed on embryonic ventricles treated with vehicle or 20 mg/kg of caffeine daily from E6.5-9.5. Differential expression (DE) analysis revealed that 124 genes and 849 transcripts were significantly altered, and differential exon usage (DEU) analysis identified 597 exons that were changed in response to prenatal caffeine exposure. Among the DE genes identified by RNA sequencing were several cardiac structural genes and genes that control DNA methylation and histone modification. Pathway analysis revealed that pathways related to cardiovascular development and diseases were significantly affected by caffeine. In addition, global cardiac DNA methylation was reduced in caffeine-treated cardiomyocytes. Collectively, these data demonstrate that caffeine exposure alters gene expression and DNA methylation in embryonic cardiomyocytes. Copyright © 2014 the American Physiological Society.

  14. Altered Neutrophil Function in Localized Juvenile Periodontitis: Intrinsic or Induced?

    Science.gov (United States)

    Agarwal, Sudha; Huang, Jian Ping; Piesco, Nicholas P; Suzuki, Jon B; Riccelli, Angelina E; Johns, Lee P

    1996-03-01

    Localized juvenile periodontitis (LJP) is an aggressive periodontal disease of familial nature. Neutrophils from a majority of patients with this disease exhibit decreased Chemotaxis with increased adherence, oxidative burst, and degranulation in response to opsonized bacteria. It is proposed that the biological basis for these altered neutrophil functions in LJP may be due either to intrinsic cell abnormalities or to the effect of factors present in the sera of LJP patients, which can modulate neutrophil functions. LJP neutrophils exhibit a lower number of receptors for chemoattractants and GP-110 molecules which are known to facilitate Chemotaxis. Furthermore, these cells exhibit lower signal transduction in response to a biological stimulus. These observations suggest that intrinsic cellular defects may be responsible for altered neutrophil functions in LJP. However, healthy neutrophils, when treated with very low concentrations of proinflammatory cytokines, also exhibit the characteristics of altered or "defective" LJP neutrophils. Additionally, healthy neutrophils, when treated with LJP serum, also exhibit many of the characteristics associated with LJP neutrophils. Attempts to identify these factors have shown that cytokines like TNF-α and/or IL1 β in LJP sera may be at least partially responsible for modulating neutrophil functions in LJP. These cytokines are primarily produced by activated macrophages, indicating a role for these cells in the etiology of LJP. The hyper-responsiveness of these cells to an immunologic challenge can result in local increases in cytokines leading to excessive bone loss and tissue damage at the site of infection, while systemic elevations in cytokines would lead to decreased neutrophil Chemotaxis, both of which are observed in LJP. Present evidence indicates that neutrophil functions are indeed altered in the majority of LJP patients. However, the biological basis for the alteration may not be due to the neutrophils themselves

  15. Preterm birth and structural brain alterations in early adulthood

    Directory of Open Access Journals (Sweden)

    Chiara Nosarti

    2014-01-01

    Full Text Available Alterations in cortical development and impaired neurodevelopmental outcomes have been described following very preterm (VPT birth in childhood and adolescence, but only a few studies to date have investigated grey matter (GM and white matter (WM maturation in VPT samples in early adult life. Using voxel-based morphometry (VBM we studied regional GM and WM volumes in 68 VPT-born individuals (mean gestational age 30 weeks and 43 term-born controls aged 19–20 years, and their association with cognitive outcomes (Hayling Sentence Completion Test, Controlled Oral Word Association Test, Visual Reproduction test of the Wechsler Memory Scale-Revised and gestational age. Structural MRI data were obtained with a 1.5 Tesla system and analysed using the VBM8 toolbox in SPM8 with a customized study-specific template. Similarly to results obtained at adolescent assessment, VPT young adults compared to controls demonstrated reduced GM volume in temporal, frontal, insular and occipital areas, thalamus, caudate nucleus and putamen. Increases in GM volume were noted in medial/anterior frontal gyrus. Smaller subcortical WM volume in the VPT group was observed in temporal, parietal and frontal regions, and in a cluster centred on posterior corpus callosum/thalamus/fornix. Larger subcortical WM volume was found predominantly in posterior brain regions, in areas beneath the parahippocampal and occipital gyri and in cerebellum. Gestational age was associated with GM and WM volumes in areas where VPT individuals demonstrated GM and WM volumetric alterations, especially in temporal, parietal and occipital regions. VPT participants scored lower than controls on measures of IQ, executive function and non-verbal memory. When investigating GM and WM alterations and cognitive outcome scores, subcortical WM volume in an area beneath the left inferior frontal gyrus accounted for 14% of the variance of full-scale IQ (F = 12.9, p < 0.0001. WM volume in posterior corpus

  16. THC alters alters morphology of neurons in medial prefrontal cortex, orbital prefrontal cortex, and nucleus accumbens and alters the ability of later experience to promote structural plasticity.

    Science.gov (United States)

    Kolb, Bryan; Li, Yilin; Robinson, Terry; Parker, Linda A

    2018-03-01

    Psychoactive drugs have the ability to alter the morphology of neuronal dendrites and spines and to influence later experience-dependent structural plasticity. If rats are given repeated injections of psychomotor stimulants (amphetamine, cocaine, nicotine) prior to being placed in complex environments, the drug experience interferes with the ability of the environment to increase dendritic arborization and spine density. Repeated exposure to Delta 9-Tetrahydrocannabinol (THC) changes the morphology of dendrites in medial prefrontal cortex (mPFC) and nucleus accumbens (NAcc). To determine if drugs other than psychomotor stimulants will also interfere with later experience-dependent structural plasticity we gave Long-Evans rats THC (0.5 mg/kg) or saline for 11 days before placing them in complex environments or standard laboratory caging for 90 days. Brains were subsequently processed for Golgi-Cox staining and analysis of dendritic morphology and spine density mPFC, orbital frontal cortex (OFC), and NAcc. THC altered both dendritic arborization and spine density in all three regions, and, like psychomotor stimulants, THC influenced the effect of later experience in complex environments to shape the structure of neurons in these three regions. We conclude that THC may therefore contribute to persistent behavioral and cognitive deficits associated with prolonged use of the drug. © 2017 Wiley Periodicals, Inc.

  17. Enteric Helminths Promote Salmonella Coinfection by Altering the Intestinal Metabolome.

    Science.gov (United States)

    Reynolds, Lisa A; Redpath, Stephen A; Yurist-Doutsch, Sophie; Gill, Navkiran; Brown, Eric M; van der Heijden, Joris; Brosschot, Tara P; Han, Jun; Marshall, Natalie C; Woodward, Sarah E; Valdez, Yanet; Borchers, Christoph H; Perona-Wright, Georgia; Finlay, B Brett

    2017-04-15

    Intestinal helminth infections occur predominantly in regions where exposure to enteric bacterial pathogens is also common. Helminth infections inhibit host immunity against microbial pathogens, which has largely been attributed to the induction of regulatory or type 2 (Th2) immune responses. Here we demonstrate an additional 3-way interaction in which helminth infection alters the metabolic environment of the host intestine to enhance bacterial pathogenicity. We show that an ongoing helminth infection increased colonization by Salmonella independently of T regulatory or Th2 cells. Instead, helminth infection altered the metabolic profile of the intestine, which directly enhanced bacterial expression of Salmonella pathogenicity island 1 (SPI-1) genes and increased intracellular invasion. These data reveal a novel mechanism by which a helminth-modified metabolome promotes susceptibility to bacterial coinfection. © The Author 2017. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail: journals.permissions@oup.com.

  18. Artificial sweeteners induce glucose intolerance by altering the gut microbiota.

    Science.gov (United States)

    Suez, Jotham; Korem, Tal; Zeevi, David; Zilberman-Schapira, Gili; Thaiss, Christoph A; Maza, Ori; Israeli, David; Zmora, Niv; Gilad, Shlomit; Weinberger, Adina; Kuperman, Yael; Harmelin, Alon; Kolodkin-Gal, Ilana; Shapiro, Hagit; Halpern, Zamir; Segal, Eran; Elinav, Eran

    2014-10-09

    Non-caloric artificial sweeteners (NAS) are among the most widely used food additives worldwide, regularly consumed by lean and obese individuals alike. NAS consumption is considered safe and beneficial owing to their low caloric content, yet supporting scientific data remain sparse and controversial. Here we demonstrate that consumption of commonly used NAS formulations drives the development of glucose intolerance through induction of compositional and functional alterations to the intestinal microbiota. These NAS-mediated deleterious metabolic effects are abrogated by antibiotic treatment, and are fully transferrable to germ-free mice upon faecal transplantation of microbiota configurations from NAS-consuming mice, or of microbiota anaerobically incubated in the presence of NAS. We identify NAS-altered microbial metabolic pathways that are linked to host susceptibility to metabolic disease, and demonstrate similar NAS-induced dysbiosis and glucose intolerance in healthy human subjects. Collectively, our results link NAS consumption, dysbiosis and metabolic abnormalities, thereby calling for a reassessment of massive NAS usage.

  19. Listeria monocytogenes transiently alters mitochondrial dynamics during infection.

    Science.gov (United States)

    Stavru, Fabrizia; Bouillaud, Frédéric; Sartori, Anna; Ricquier, Daniel; Cossart, Pascale

    2011-03-01

    Mitochondria are essential and highly dynamic organelles, constantly undergoing fusion and fission. We analyzed mitochondrial dynamics during infection with the human bacterial pathogen Listeria monocytogenes and show that this infection profoundly alters mitochondrial dynamics by causing transient mitochondrial network fragmentation. Mitochondrial fragmentation is specific to pathogenic Listeria monocytogenes, and it is not observed with the nonpathogenic Listeria innocua species or several other intracellular pathogens. Strikingly, the efficiency of Listeria infection is affected in cells where either mitochondrial fusion or fission has been altered by siRNA treatment, highlighting the relevance of mitochondrial dynamics for Listeria infection. We identified the secreted pore-forming toxin listeriolysin O as the bacterial factor mainly responsible for mitochondrial network disruption and mitochondrial function modulation. Together, our results suggest that the transient shutdown of mitochondrial function and dynamics represents a strategy used by Listeria at the onset of infection to interfere with cellular physiology.

  20. Sleep deprivation alters valuation signals in the ventromedial prefrontal cortex

    Directory of Open Access Journals (Sweden)

    Camilo eLibedinsky

    2011-10-01

    Full Text Available Even a single night of total sleep-deprivation (SD can have dramatic effects on economic decision making. Here we tested the novel hypothesis that SD influences economic decisions by altering the valuation process. Using functional magnetic resonance imaging (fMRI we identified value signals related to the anticipation and the experience of monetary and social rewards (attractive female faces. We then derived decision value signals that were predictive of each participant’s willingness to exchange money for brief views of attractive faces in an independent market task. Strikingly, SD altered decision value signals in ventromedial prefrontal cortex (VMPFC in proportion to the corresponding change in economic preferences. These changes in preference were independent of the effects of SD on attention and vigilance. Our results provide novel evidence that signals in VMPFC track the current state of the individual, and thus reflect not static but constructed preferences.

  1. Toxic Knowledge: Self-Alteration Through Child Abuse Work.

    Science.gov (United States)

    Sigad, Laura I; Davidov, Jonathan; Lev-Wiesel, Rachel; Eisikovits, Zvi

    2016-02-01

    The purpose of the present article is to examine the multiple ways in which the private lives of professionals are affected by involvement with child abuse intervention and prevention. Using a descriptive-phenomenological perspective and 40 in-depth interviews with professionals to present a model based on qualitative data, we studied the ways in which child abuse professionals conceptualize, understand, and integrate their experiences into their personal and family lives. We find that the process of internalizing child abuse knowledge occurs in two domains: One affirms or denies the existence of the phenomenon; the other concerns the strategies used to contend with the effects of working in abuse. Knowledge of child abuse is toxic, in the sense that it serves as a catalyst leading to the alteration of one's self-perception and parental identity. We present a typology of self-alteration resulting from child abuse knowledge and describe the mechanism of this change. © The Author(s) 2014.

  2. Alterations of the visual pathways in congenital blindness

    DEFF Research Database (Denmark)

    Ptito, Maurice; Schneider, Fabien C G; Paulson, Olaf B

    2008-01-01

    We used whole brain MRI voxel-based morphometry (VBM) to study the anatomical organization of the visual system in congenitally blind (CB) adults. Eleven CB without a history of visual perception were compared with 21 age- and sex-matched normal-sighted controls (NS). CB showed significant atrophy...... of the geniculo-striate system, encompassing the optic nerves, the optic chiasm, the optic radiations and the primary visual cortex (BA17). The volume decrease in BA17 reached 25% in both hemispheres. The pulvinar and its projections to the associative visual areas were also dramatically altered, BA18....../19 and the middle temporal cortex (MT) showing volume reductions of up to 20%. Additional significant white matter alterations were observed in the inferior longitudinal tract and in the posterior part of the corpus callosum, which links the visual areas of both hemispheres. Our data indicate that the afferent...

  3. Subclinical depressive symptoms during late midlife and structural brain alterations

    DEFF Research Database (Denmark)

    Osler, Merete; Sørensen, Lauge; Rozing, Maarten

    2018-01-01

    at age 51, 56, and 59 years, magnetic resonance imaging was performed at age 59. All data processing was performed using the Freesurfer software package except for the texture-scores that were computed using in-house software. Structural brain alterations and associations between depressive symptoms......We explored whether depressive symptoms measured three times during midlife were associated with structural brain alterations quantified using magnetic resonance imaging measurements of volume, cortical thickness, and intensity texture. In 192 men born in 1953 with depressive symptoms measured...... and brain structure outcomes were tested using Pearson's correlation, t test, and linear regression. Depressive symptoms at age 51 showed clear inverse correlations with total gray matter, pallidum, and hippocampal volume with the strongest estimate for hippocampal volume (r = -.22, p 

  4. Altered glial plasticity in animal models for mood disorders.

    Science.gov (United States)

    Czéh, Boldizsár; Fuchs, Eberhard; Flügge, Gabriele

    2013-10-01

    Numerous clinical evidences support the notion that glial changes in fronto-limbic brain areas could contribute to the pathophysiology of mood disorders. Glial alterations have been reported not only in patients, but also in various kinds of animal models for depression. Molecular and cellular data suggest that all the major classes of glial cells are affected in these conditions, including astrocytes, oligodendrocytes, NG2-positive cells and microglia. The aim of this review was to summarize the currently available experimental results demonstrating alterations in glial morphology and functioning in animal models for mood disorders. Better understanding of these glial changes affecting neuronal activity could help us to identify novel targets for the development of antidepressant drugs.

  5. ALTERATION OF U(VI)-PHASES UNDER OXIDIZING CONDITIONS

    Energy Technology Data Exchange (ETDEWEB)

    A.P. Deditius; S. Utsunomiya; R.C. Ewing

    2006-02-21

    Uranium-(VI) phases are the primary alteration products of the UO{sub 2} in spent nuclear fuel and the UO{sub 2+x}, in natural uranium deposits. The U(VI)-phases generally form sheet structures of edge-sharing UO{sub 2}{sup 2+} polyhedra. The complexity of these structures offers numerous possibilities for coupled-substitutions of trace metals and radionuclides. The incorporation of radionuclides into U(VI)-structures provides a potential barrier to their release and transport in a geologic repository that experiences oxidizing conditions. In this study, we have used natural samples of UO{sub 2+x}, to study the U(VI)-phases that form during alteration and to determine the fate of the associated trace elements.

  6. Major depressive disorder alters perception of emotional body movements

    Directory of Open Access Journals (Sweden)

    Morten eKaletsch

    2014-01-01

    Full Text Available Much recent research has shown an association between mood disorders and an altered emotion perception. However, these studies were conducted mainly with stimuli such as faces. This is the first study to examine possible differences in how people with major depressive disorder (MDD and healthy controls perceive emotions expressed via body movements. 30 patients with MDD and 30 healthy controls observed video scenes of human interactions conveyed by point–light displays (PLDs. They rated the depicted emotions and judged their confidence in their rating. Results showed that patients with MDD rated the depicted interactions more negatively than healthy controls. They also rated interactions with negative emotionality as being more intense and were more confident in their ratings. It is concluded that patients with MDD exhibit an altered emotion perception compared to healthy controls when rating emotions expressed via body movements depicted in PLDs.

  7. Epilepsy in patients with GRIN2A alterations

    DEFF Research Database (Denmark)

    von Stülpnagel, Celina; Ensslen, M; Møller, R S

    2017-01-01

    OBJECTIVE: To delineate the genetic, neurodevelopmental and epileptic spectrum associated with GRIN2A alterations with emphasis on epilepsy treatment. METHODS: Retrospective study of 19 patients (7 females; age: 1-38 years; mean 10.1 years) with epilepsy and GRIN2A alteration. Genetic variants were...... classified according to the guidelines and recommendations of the American College of Medical Genetics (ACMG). Clinical findings including epilepsy classification, treatment, EEG findings, early childhood development and neurodevelopmental outcome were collected with an electronic questionnaire. RESULTS: 7...... indicate that children with epilepsy due to pathogenic GRIN2A mutations present with different clinical phenotypes and a spectrum of seizure types in the context of a pharmacoresistant epilepsy providing information for clinicians treating children with this form of genetically determined epileptic...

  8. Alterations in HIV-1 LTR promoter activity during AIDS progression

    International Nuclear Information System (INIS)

    Hiebenthal-Millow, Kirsten; Greenough, Thomas C.; Bretttler, Doreen B.; Schindler, Michael; Wildum, Steffen; Sullivan, John L.; Kirchhoff, Frank

    2003-01-01

    HIV-1 variants evolving in AIDS patients frequently show increased replicative capacity compared to those present during early asymptomatic infection. It is known that late stage HIV-1 variants often show an expanded coreceptor tropism and altered Nef function. In the present study we investigated whether enhanced HIV-1 LTR promoter activity might also evolve during disease progression. Our results demonstrate increased LTR promoter activity after AIDS progression in 3 of 12 HIV-1-infected individuals studied. Further analysis revealed that multiple alterations in the U3 core-enhancer and in the transactivation-response (TAR) region seem to be responsible for the enhanced functional activity. Our findings show that in a subset of HIV-1-infected individuals enhanced LTR transcription contributes to the increased replicative potential of late stage virus isolates and might accelerate disease progression

  9. Insulin resistance alters islet morphology in nondiabetic humans

    DEFF Research Database (Denmark)

    Mezza, Teresa; Muscogiuri, Giovanna; Sorice, Gian Pio

    2014-01-01

    Type 2 diabetes is characterized by poor glucose uptake in metabolic tissues and manifests when insulin secretion fails to cope with worsening insulin resistance. In addition to its effects on skeletal muscle, liver, and adipose tissue metabolism, it is evident that insulin resistance also affects...... pancreatic β-cells. To directly examine the alterations that occur in islet morphology as part of an adaptive mechanism to insulin resistance, we evaluated pancreas samples obtained during pancreatoduodenectomy from nondiabetic subjects who were insulin-resistant or insulin-sensitive. We also compared...... insulin sensitivity, insulin secretion, and incretin levels between the two groups. We report an increased islet size and an elevated number of β- and α-cells that resulted in an altered β-cell-to-α-cell area in the insulin- resistant group. Our data in this series of studies suggest that neogenesis from...

  10. Osteological alterations in the tucuxi Sotalia fluviatilis (cetacea, delphinidae

    Directory of Open Access Journals (Sweden)

    Daniela de C. Fettuccia

    2013-09-01

    Full Text Available We present a description of osteological alterations observed in the tucuxi, Sotalia fluviatilis (Gervais, 1853 from a sample of 43 specimens. Fractures were the most frequent alterations in the sample (16%, occurring in various regions of the skeleton such as the ribs, hyoid apparatus, transverse and neural processes of vertebrae and scapula. We observed three individuals with ankylosis between the cervical vertebrae and two individuals with morphological changes (cranio-caudally elongated hemal arch and flattened cranial margin of the scapula. The only observed pathology was a case of osteomyelitis in the left dentary, which caused the loss of teeth, deformation of the associated alveoli and the formation of a medial fistula (lingual for drainage of purulent material. This represents the first record of osteomyelitis in S. fluviatilis.

  11. A single natural nucleotide mutation alters bacterial pathogen host tropism.

    Science.gov (United States)

    Viana, David; Comos, María; McAdam, Paul R; Ward, Melissa J; Selva, Laura; Guinane, Caitriona M; González-Muñoz, Beatriz M; Tristan, Anne; Foster, Simon J; Fitzgerald, J Ross; Penadés, José R

    2015-04-01

    The capacity of microbial pathogens to alter their host tropism leading to epidemics in distinct host species populations is a global public and veterinary health concern. To investigate the molecular basis of a bacterial host-switching event in a tractable host species, we traced the evolutionary trajectory of the common rabbit clone of Staphylococcus aureus. We report that it evolved through a likely human-to-rabbit host jump over 40 years ago and that only a single naturally occurring nucleotide mutation was required and sufficient to convert a human-specific S. aureus strain into one that could infect rabbits. Related mutations were identified at the same locus in other rabbit strains of distinct clonal origin, consistent with convergent evolution. This first report of a single mutation that was sufficient to alter the host tropism of a microorganism during its evolution highlights the capacity of some pathogens to readily expand into new host species populations.

  12. Alterations in Gut Microbiota and Post-Traumatic Osteoarthritis

    Science.gov (United States)

    2017-09-01

    knee joint under conditions of altered gut microbiota caused by genetic background or chronic antibiotic treatment. Animal experimentation was...worked: 0.5 Contribution to Project: Dr. van der Meulen has worked to oversee experimental procedures on the experimental animals and in data...worked: 8 Contribution to Project: Ms. Luna has been led animal breeding and experimental manipulations of the animals and coordinated final data

  13. Heavy Metals and Epigenetic Alterations in Brain Tumors

    OpenAIRE

    Caffo, Maria; Caruso, Gerardo; Fata, Giuseppe La; Barresi, Valeria; Visalli, Maria; Venza, Mario; Venza, Isabella

    2014-01-01

    Heavy metals and their derivatives can cause various diseases. Numerous studies have evaluated the possible link between exposure to heavy metals and various cancers. Recent data show a correlation between heavy metals and aberration of genetic and epigenetic patterns. From a literature search we noticed few experimental and epidemiological studies that evaluate a possible correlation between heavy metals and brain tumors. Gliomas arise due to genetic and epigenetic alterations of glial cells...

  14. Virus Innexins induce alterations in insect cell and tissue function.

    Science.gov (United States)

    Hasegawa, Daniel K; Erickson, Stephanie L; Hersh, Bradley M; Turnbull, Matthew W

    2017-04-01

    Polydnaviruses are dsDNA viruses that induce immune and developmental alterations in their caterpillar hosts. Characterization of polydnavirus gene families and family members is necessary to understand mechanisms of pathology and evolution of these viruses, and may aid to elucidate the role of host homologues if present. For example, the polydnavirus vinnexin gene family encodes homologues of insect gap junction genes (innexins) that are expressed in host immune cells (hemocytes). While the roles of Innexin proteins and gap junctions in insect immunity are largely unclear, we previously demonstrated that Vinnexins form functional gap junctions and alter the junctional characteristics of a host Innexin when co-expressed in paired Xenopus oocytes. Here, we test the effect of ectopic vinnexin expression on host cell physiology using both a lepidopteran cell culture model and a dipteran whole organism model. Vinnexin expression in the cell culture system resulted in gene-specific alterations in cell morphology and a slight, but non-statistically significant, reduction in gap junction activity as measured by dye transfer, while ectopic expression of a lepidopteran innexin2 gene led to morphological alterations and increase in gap junction activity. Global ectopic expression in the model dipteran, Drosophila melanogaster, of one vinnexin (vinnexinG) or D. melanogaster innexin2 (Dm-inx2) resulted in embryonic lethality, while expression of the other vinnexin genes had no effect. Furthermore, ectopic expression of vinnexinG, but not other vinnexin genes or Dm-inx2, in D. melanogaster larval gut resulted in developmental arrest in the pupal stage. These data indicate the vinnexins likely have gene-specific roles in host manipulation. They also support the use of Drosophila in further analysis of the role of Vinnexins and other polydnavirus genes in modifying host physiological processes. Finally, our findings suggest the vinnexin genes may be useful to perturb and

  15. Failure of probenecid to alter the pharmacokinetics of ceforanide.

    OpenAIRE

    Jovanovich, J F; Saravolatz, L D; Burch, K; Pohlod, D J

    1981-01-01

    This investigation evaluated the effect of probenecid on ceforanide concentrations in eight healthy volunteers. Each volunteer was given 1 or 2 g of ceforanide either alone or with 1 g of probenecid. Concentrations of ceforanide in plasma, urine, and saliva were then measured. Probenecid did not alter the plasma concentrations of ceforanide, nor did it affect the urinary excretion of this agent. Ceforanide was not secreted into saliva in any detectable amount either when administered alone or...

  16. PIK3CA alterations in Middle Eastern ovarian cancers

    Directory of Open Access Journals (Sweden)

    Uddin Shahab

    2009-07-01

    Full Text Available Abstract Background PI3K/AKTsignaling pathway plays an important role in cell growth, proliferation, and tumorgenesis of various malignancies. This signaling pathway has been shown to be frequently altered in several human cancers including ovarian cancers. However the role of this oncogenic signaling pathway has not been explored in the Middle Eastern epithelial ovarian cancer (EOC. Therefore, we investigated PI3K/AKT genetic alterations such as PIK3CA amplification, PIK3CA mutation, PTEN protein loss and their relationships with various clinicopathological characteristics in 156 EOCs. Results Fluorescence in situ hybridization (FISH technique and DNA sequencing were used to analyze PIK3CA amplification and mutation respectively. Expression of PIK3CA protein expression (p110 α, PTEN, p-AKT and Ki-67 was analyzed by immunohistochemistry. PIK3CA amplification was seen in 54 of 152 (35.5% EOC cases analyzed; PIK3CA gene mutations in 6/153 EOC (3.9%; KRAS mutations in 3/154 EOC (1.9%, BRAF mutations in 3/156 EOC (1.9%, p53 mutation in 50/154 EOC (32.5%, and loss of PTEN protein expression in 33/144 EOC (22.9%. p110 α overexpression was associated with increased phosphorylation of AKT-Ser 473 and with the proliferation marker Ki-67. Conclusion Our data showed mutual exclusivity between the molecular event of PIK3CA amplification and mutations in PIK3CA, KRAS, BRAF genes, which suggests that each of these alterations may individually be sufficient to drive ovarian tumor pathogenesis independently. High prevalence of genetic alterations in PI3K/AKT pathway in a Middle Eastern ovarian carcinoma provides genetic evidence supporting the notion that dysregulated PI3K/AKT pathways play an important role in the pathogenesis of ovarian cancers.

  17. Alterations in Gut Microbiota and Post-Traumatic Osteoarthritis

    Science.gov (United States)

    2016-09-01

    circulating sex hormones may influence microbiome-dependent phenotypes. In humans, the microbiome is altered during pregnancy ,(74) providing further...Goodrich JK, Cullender TC, et al. Host remodeling of the gut microbiome and metabolic changes during pregnancy . Cell. 2012;150(3):470–80. 75. McCabe LR...Osteoporosis in gastrointestinal, pancreatic and hepatic diseases. In: Marcus R, Feldman D, Nelson DA, Rosen CJ, editors. Osteoporosis. 3rd ed., vol. 2. San

  18. Possible alterations of the gravitational field in a superconductor

    OpenAIRE

    Ummarino, G. A.

    2000-01-01

    In this paper I calculate the possible alteration of the gravitational field in a superconductor by using the time-dependent Ginzburg-Landau equations (TDGL). I compare the behaviour of a high-Tc superconductor (HTCS) like YBa_2Cu_3O_7 (YBCO) with a classical low-Tc superconductor (LTCS) like Pb. Finally, I discuss what values of the parameters characterizing a superconductor can enhance the reduction of gravitational field.

  19. Vitamin D alteration associated with obesity and bariatric surgery

    OpenAIRE

    Lespessailles, Eric; Toumi, Hechmi

    2017-01-01

    Obesity and severe obesity constitute growing serious health problems reaching epidemic proportion in most countries. Interactions and relationships between obesity and bone tissue and its metabolism are complex but are more and more studied and recognized. Obesity is associated with an altered hormonal profile including particularly bone-regulating hormones like vitamin D. Bariatric surgery procedures, thanks to their effectiveness to achieve therapeutic endpoints for comorbidities associate...

  20. Neural Alterations in Acquired Age-Related Hearing Loss

    OpenAIRE

    Mudar, Raksha A.; Husain, Fatima T.

    2016-01-01

    Hearing loss is one of the most prevalent chronic health conditions in older adults. Growing evidence suggests that hearing loss is associated with reduced cognitive functioning and incident dementia. In this mini-review, we briefly examine literature on anatomical and functional alterations in the brains of adults with acquired age-associated hearing loss, which may underlie the cognitive consequences observed in this population, focusing on studies that have used structural and functional m...

  1. Physiological and enzymatic alterations in papaya seed during storage

    OpenAIRE

    Dias, Denise Cunha Fernandes Dos Santos; Estanislau, Wagner Tompson; Finger, Fernando Luiz; Alvarenga, Eveline Mantovani; Dias, Luiz Antônio Dos Santos

    2010-01-01

    This study was done to evaluate the physiological and enzymatic alterations in papaya (Carica papaya L.) seeds during storage period. Seeds were extracted from mature fruits of Formosa group papaya hybrid Tainung 01. The sarcotesta was removed by rubbing the seeds on a wire screen under running water and then dried to the moisture content (MC) of 5, 8 or 11% The seeds were packed in multilayer paper bags, polyethylene bags, aluminum foil pouch and metallic canisters and stored for 15 months u...

  2. Alterations in polyadenylation and its implications for endocrine disease

    Directory of Open Access Journals (Sweden)

    Anders eRehfeld

    2013-05-01

    Full Text Available IntroductionPolyadenylation is the process in which the pre-mRNA is cleaved at the poly(A site and a poly(A tail is added - a process necessary for normal mRNA formation. Genes with multiple poly(A sites can undergo alternative polyadenylation, producing distinct mRNA isoforms with different 3’ untranslated regions (3’ UTRs and in some cases different coding regions. Two thirds of all human genes undergo alternative polyadenylation. The efficiency of the polyadenylation process regulates gene expression and alternative polyadenylation plays an important part in post-transcriptional regulation, as the 3’ UTR contains various cis-elements associated with post-transcriptional regulation, such as target sites for microRNAs and RNA-binding proteins.Implications of alterations in polyadenylation for endocrine diseaseAlterations in polyadenylation have been found to be causative of neonatal diabetes and IPEX (immune dysfunction, polyendocrinopathy, enteropathy, X-linked and to be associated with type I and II diabetes, pre-eclampsia, fragile X-associated premature ovarian insufficiency, ectopic Cushing syndrome and many cancer diseases, including several types of endocrine tumor diseases.PerspectivesRecent developments in high-throughput sequencing have made it possible to characterize polyadenylation genome-wide. Antisense elements inhibiting or enhancing specific poly(A site usage can induce desired alterations in polyadenylation, and thus hold the promise of new therapeutic approaches. SummaryThis review gives a detailed description of alterations in polyadenylation in endocrine disease, an overview of the current literature on polyadenylation and summarizes the clinical implications of the current state of research in this field.

  3. VIDEOFLUOROSCOPIC SWALLOWING STUDY: esophageal alterations in patients with dysphagia

    Directory of Open Access Journals (Sweden)

    Betina SCHEEREN

    2014-09-01

    Full Text Available Context Videofluoroscopic swallowing study is a dynamic exam and allows the evaluation of the complete swallowing process. However, most published studies have only reported alterations in the oropharynx and pharyngoesophageal transition, leaving the analysis of the esophagus as a secondary goal. Objectives The goal of this study was to investigate the prevalence of alterations in the esophageal phase thorough videofluoroscopic swallowing study in patients with dysphagia. Methods Consecutive patients with dysphagia who underwent videofluoroscopic swallowing study including esophageal analysis between May 2010 and May 2012 had their exams retrospectively reviewed. Patients were classified into two groups: Group I - without a pre-established etiological diagnosis and Group II - with neurological disease. During the exam, the patients ingested three different consistencies of food (liquid, pasty and solid contrasted with barium sulfate and 19 items were analyzed according to a protocol. The esophageal phase was considered abnormal when one of the evaluated items was compromised. Results Three hundred and thirty-three (n = 333 consecutive patients were studied - 213 (64% in Group I and 120 (36% in Group II. Esophageal alterations were found in 104 (31% patients, with a higher prevalence in Group I (36.2%, especially on the items esophageal clearance (16.9% and tertiary contractions (16.4%. It was observed that 12% of individuals in Group I only presented alterations on the esophageal phase. Conclusion Evaluation of the esophageal phase of swallowing during videofluoroscopic swallowing study detects abnormalities in patients with cervical dysphagia, especially in the group without pre-established etiological diagnosis.

  4. Ocean acidification alters temperature and salinity preferences in larval fish.

    Science.gov (United States)

    Pistevos, Jennifer C A; Nagelkerken, Ivan; Rossi, Tullio; Connell, Sean D

    2017-02-01

    Ocean acidification alters the way in which animals perceive and respond to their world by affecting a variety of senses such as audition, olfaction, vision and pH sensing. Marine species rely on other senses as well, but we know little of how these might be affected by ocean acidification. We tested whether ocean acidification can alter the preference for physicochemical cues used for dispersal between ocean and estuarine environments. We experimentally assessed the behavioural response of a larval fish (Lates calcarifer) to elevated temperature and reduced salinity, including estuarine water of multiple cues for detecting settlement habitat. Larval fish raised under elevated CO 2 concentrations were attracted by warmer water, but temperature had no effect on fish raised in contemporary CO 2 concentrations. In contrast, contemporary larvae were deterred by lower salinity water, where CO 2 -treated fish showed no such response. Natural estuarine water-of higher temperature, lower salinity, and containing estuarine olfactory cues-was only preferred by fish treated under forecasted high CO 2 conditions. We show for the first time that attraction by larval fish towards physicochemical cues can be altered by ocean acidification. Such alterations to perception and evaluation of environmental cues during the critical process of dispersal can potentially have implications for ensuing recruitment and population replenishment. Our study not only shows that freshwater species that spend part of their life cycle in the ocean might also be affected by ocean acidification, but that behavioural responses towards key physicochemical cues can also be negated through elevated CO 2 from human emissions.

  5. Influence on radiogenic alterations in hematopoiesis - Situation and possibilities

    International Nuclear Information System (INIS)

    Kehrberg, G.; Rose, H.; Saul, G.; Riessbeck, K.H.

    1985-01-01

    Radiogenic alterations of hematopoiesis are a main topic in radiobiological investigations. By further elucidation of the regulatory mechanisms possibly follow new starting points to accelerate the regeneration of stem cells, still capable of proliferating, or differentiation of most endangered and nearly irretrievable cell populations by drugs. The present state is discussed concerning the application of anabolics, endotoxins, thymic extracts, cyanoethylurea, and lithium carbonate as well as parenteral nutrition and competition of stem cells. (author)

  6. Stuttering inhibition via altered auditory feedback during scripted telephone conversations.

    Science.gov (United States)

    Hudock, Daniel; Kalinowski, Joseph

    2014-01-01

    Overt stuttering is inhibited by approximately 80% when people who stutter read aloud as they hear an altered form of their speech feedback to them. However, levels of stuttering inhibition vary from 60% to 100% depending on speaking situation and signal presentation. For example, binaural presentations of delayed auditory feedback (DAF) and frequency-altered feedback (FAF) have been shown to reduce stuttering by approximately 57% during scripted telephone conversations. To examine stuttering frequency under monaural auditory feedback with one combination of DAF with FAF (COMBO-2) and two combinations of DAF with FAF (COMBO-4) during scripted telephone conversations. Nine adult participants who stutter called 15 local businesses during scripted telephone conversations; each condition consisted of five randomized telephone calls. Conditions consisted of (1) baseline (i.e. non-altered feedback), (2) COMBO-2 (i.e. 50-ms delay with a half octave spectral shift up), and (3) COMBO-4 (i.e. 200-ms delay and a half octave spectral shift down in addition to the COMBO-2). Participants wore a supra-aural headset with a dynamic condenser microphone while holding a receiver to their contralateral ear when making telephone calls. Stuttering was significantly reduced during both altered auditory feedback (AAF) conditions by approximately 65%. Furthermore, a greater reduction in stuttering was revealed during the COMBO with four effects (74%) as compared with the COMBO with two effects (63%). Results from the current study support prior research reporting decreased stuttering under AAF during scripted telephone conversations. Findings that stuttering was significantly reduced to a greater extent under the COMBO with four effects condition suggest that second signals reduce stuttering along a continuum. Additionally, findings support prior research results of decreased stuttering frequency under AAF during hierarchically difficult speaking situations. Clinical application of these

  7. Visible light alters yeast metabolic rhythms by inhibiting respiration

    OpenAIRE

    Robertson, James Brian; Davis, Chris R.; Johnson, Carl Hirschie

    2013-01-01

    In some organisms, respiration fluctuates cyclically, and these rhythms can be a sensitive gauge of metabolism. Constant or pulsatile exposure of yeast to visible wavelengths of light significantly alters and/or initiates these respiratory oscillations, revealing a further dimension of the challenges to yeast living in natural environments. Our results also have implications for the use of light as research tools—e.g., for excitation of fluorescence microscopically—even in organisms such as y...

  8. Connectomics and Neuroticism: An Altered Functional Network Organization

    OpenAIRE

    Servaas, Michelle N; Geerligs, Linda; Renken, Remco J; Marsman, Jan-Bernard C; Ormel, Johan; Riese, Harriëtte; Aleman, André

    2014-01-01

    The personality trait neuroticism is a potent risk marker for psychopathology. Although the neurobiological basis remains unclear, studies have suggested that alterations in connectivity may underlie it. Therefore, the aim of the current study was to shed more light on the functional network organization in neuroticism. To this end, we applied graph theory on resting-state functional magnetic resonance imaging (fMRI) data in 120 women selected based on their neuroticism score. Binary and weig...

  9. Modeling Human Perception of Orientation in Altered Gravity

    Directory of Open Access Journals (Sweden)

    Torin K. Clark

    2015-05-01

    Full Text Available Altered gravity environments, such as those experienced by astronauts, impact spatial orientation perception and can lead to spatial disorientation and sensorimotor impairment. To more fully understand and quantify the impact of altered gravity on orientation perception, several mathematical models have been proposed. The utricular shear, tangent, and the idiotropic vector models aim to predict static perception of tilt in hyper-gravity. Predictions from these prior models are compared to the available data, but are found to systematically err from the perceptions experimentally observed. Alternatively, we propose a modified utricular shear model for static tilt perception in hyper-gravity. Previous dynamic models of vestibular function and orientation perception are limited to 1 G. Specifically, they fail to predict the characteristic overestimation of roll tilt observed in hyper-gravity environments. To address this, we have proposed a modification to a previous observer-type canal otolith interaction model based upon the hypothesis that the central nervous system treats otolith stimulation in the utricular plane differently than stimulation out of the utricular plane. Here we evaluate our modified utricular shear and modified observer models in four altered gravity motion paradigms: a static roll tilt in hyper-gravity, b static pitch tilt in hyper-gravity, c static roll tilt in hypo-gravity, and d static pitch tilt in hypo-gravity. The modified models match available data in each of the conditions considered. Our static modified utricular shear model and dynamic modified observer model may be used to help quantitatively predict astronaut perception of orientation in altered gravity environments.

  10. The partitioning of uranium and neptunium onto hydrothermally altered concrete

    International Nuclear Information System (INIS)

    Zhao, P.; Allen, P.G.; Sylwester, E.R.; Viani, B.E.

    2000-01-01

    Partition coefficients (K d ) of U(VI) and Np(V) on untreated and hydrothermally altered concrete were measured in 0.01 M NaCl and 0.01 M NaHCO 3 solutions as functions of concentration of the radionuclides, pH, and time. The partition coefficients for both U(VI) and Np(V) on hydrothermally altered concrete are significantly lower than those on untreated concrete. The partition of both U(VI) and Np(V) are pH dependent, although the pH dependence does not appear to reflect precipitation of U and Np-bearing phases. Both sorption and precipitation are likely processes controlling partitioning of U to concrete; sorption is the most likely process controlling the partitioning of Np to concrete. The presence of 0.01 M carbonate species in solution decreases K d of U(VI) for both hydrothermally altered and untreated concrete from ≥ 10 4 mL/g to ∝ 400 to 1000 mL/g indicating a significant impact on U(VI) sorption. In contrast, the presence of carbonate only reduced the K d of Np(V) by one order of magnitude or less. X-ray absorption spectroscopy analysis of U/concrete mixtures at different pHs and times indicate that uranyl ions are partitioned as monomeric species on untreated concrete, but oligomeric species on hydrothermally altered concrete. Similar analysis of Np/concrete mixtures shows that about half of the partitioned Np(V) is reduced to Np(IV) over a period of 6 months. (orig.)

  11. Gravitropism of cucumber hypocotyls: biophysical mechanism of altered growth

    Science.gov (United States)

    Cosgrove, D. J.

    1990-01-01

    The biophysical basis for the changes in cell elongation rate during gravitropism was examined in aetiolated cucumber (Cucumis sativus L.) hypocotyls. Bulk osmotic pressures on the two sides of the stem and in the epidermal cells were not altered during the early time course of gravitropism. By the pressure-probe technique, a small increase in turgor (0.3 bar, 30 kPa) was detected on the upper (inhibited) side, whereas there was a negligible decrease in turgor on the lower (stimulated) side. These small changes in turgor and water potential appeared to be indirect, passive consequences of the altered growth and the small resistance for water movement from the xylem, and indicated that the change in growth was principally due to changes in wall properties. The results indicate that the hydraulic conductance of the water-transport pathway was large (.25 h-1 bar-1) and the water potential difference supporting cell expansion was no greater than 0.3 bar (30 kPa). From pressure-block experiments, it appeared that upon gravitropic stimulation (1) the yield threshold of the lower half of the stem did not decrease and (2) the wall on the upper side of the stem was not made more rigid by a cross-linking process. Mechanical measurements of the stress/strain properties of the walls showed that the initial development of gravitropism did not involve an alteration of the mechanical behaviour of the isolated walls. Thus, gravitropism in cucumber hypocotyls occurs principally by an alteration of the wall relaxation process, without a necessary change in wall mechanical properties.

  12. Radiodiagnosis of pulmonary alterations in systemic lupus erythematosus patients

    Energy Technology Data Exchange (ETDEWEB)

    Kamenetskij, M.S.; Lezova, T.F.; Kajzerman, I.A.; Sinyachenko, O.V.; Dyadyk, A.I.; Nikolenko, Yu.I. (Donetskij Meditsinskij Inst. (Ukrainian SSR))

    X-ray examination was carried out in 170 patients with systemic lupus erythematosus. Certain parameters of specific immunity were studied in 60 of them, while X-ray data were compared with morphological findings on autopsy in 20 cases. A tendency toward escalation of specific cell and humoral parameters was discovered in pulmonary lesion, predetermined by vasculitis and perivasculitis, as well as inflammatory and fibrotic alterations in the interstitial tissue.

  13. Radiodiagnosis of pulmonary alterations in systemic lupus erythematosus patients

    International Nuclear Information System (INIS)

    Kamenetskij, M.S.; Lezova, T.F.; Kajzerman, I.A.; Sinyachenko, O.V.; Dyadyk, A.I.; Nikolenko, Yu.I.

    1982-01-01

    X-ray examination was carried out in 170 patients with systemic lupus erythematosus. Certain parameters of specific immunity were studied in 60 of them, while X-ray data were compared with morphological findings on autopsy in 20 cases. A tendency toward escalation of specific cell and humoral parameters was discovered in pulmonary lesion, predetermined by vasculitis and perivasculitis, as well as inflammatory and fibrotic alterations in the interstitial tissue

  14. Peptide fibrils with altered stability, activity, and cell selectivity

    OpenAIRE

    Chen, Long; Liang, Jun F.

    2013-01-01

    Peptides have some unique and superior features compared to proteins. However, the use of peptides as therapeutics is hampered by their low stability and cell selectivity. In this study, a new lytic peptide (CL-1, FLGALFRALSRLL) was constructed. Under the physiological condition, peptide CL-1 self-assembled into dynamically stable aggregates with fibrils-like structures. Aggregated CL-1 demonstrated dramatically altered activity and stability in comparison with single molecule CL-1 and other ...

  15. Understanding and Targeting Epigenetic Alterations in Acquired Bone Marrow Failure

    Science.gov (United States)

    2014-05-01

    the age of 40.7 In this issue of Haematologica, West et al. begin to unrav- el the genetic alterations that frequently occur together and col- laborate ...10.1182/blood-2011-11-394932 Tehranchi, R., P.S. Woll, K. Anderson, N. Buza- Vidas , T. Mizukami, A.J. Mead, I. Astrand-Grundström, B. Strömbeck, A. Horvat

  16. Aging induced ER stress alters sleep and sleep homeostasis

    Science.gov (United States)

    Brown, Marishka K.; Chan, May T.; Zimmerman, John E.; Pack, Allan I.; Jackson, Nicholas E.; Naidoo, Nirinjini

    2014-01-01

    Alterations in the quality, quantity and architecture of baseline and recovery sleep have been shown to occur during aging. Sleep deprivation induces endoplasmic reticular (ER) stress and upregulates a protective signaling pathway termed the unfolded protein response (UPR). The effectiveness of the adaptive UPR is diminished by age. Previously, we showed that endogenous chaperone levels altered recovery sleep in Drosophila melanogaster. We now report that acute administration of the chemical chaperone sodium 4-phenylbutyrate (PBA) reduces ER stress and ameliorates age-associated sleep changes in Drosophila. PBA consolidates both baseline and recovery sleep in aging flies. The behavioral modifications of PBA are linked to its suppression of ER stress. PBA decreased splicing of x-box binding protein 1 (XBP1) and upregulation of phosphorylated elongation initiation factor 2 α (p-eIF2α), in flies that were subjected to sleep deprivation. We also demonstrate that directly activating ER stress in young flies fragments baseline sleep and alters recovery sleep. Alleviating prolonged/sustained ER stress during aging contributes to sleep consolidation and improves recovery sleep/ sleep debt discharge. PMID:24444805

  17. Prenatal stress alters amygdala functional connectivity in preterm neonates.

    Science.gov (United States)

    Scheinost, Dustin; Kwon, Soo Hyun; Lacadie, Cheryl; Sze, Gordon; Sinha, Rajita; Constable, R Todd; Ment, Laura R

    2016-01-01

    Exposure to prenatal and early-life stress results in alterations in neural connectivity and an increased risk for neuropsychiatric disorders. In particular, alterations in amygdala connectivity have emerged as a common effect across several recent studies. However, the impact of prenatal stress exposure on the functional organization of the amygdala has yet to be explored in the prematurely-born, a population at high risk for neuropsychiatric disorders. We test the hypothesis that preterm birth and prenatal exposure to maternal stress alter functional connectivity of the amygdala using two independent cohorts. The first cohort is used to establish the effects of preterm birth and consists of 12 very preterm neonates and 25 term controls, all without prenatal stress exposure. The second is analyzed to establish the effects of prenatal stress exposure and consists of 16 extremely preterm neonates with prenatal stress exposure and 10 extremely preterm neonates with no known prenatal stress exposure. Standard resting-state functional magnetic resonance imaging and seed connectivity methods are used. When compared to term controls, very preterm neonates show significantly reduced connectivity between the amygdala and the thalamus, the hypothalamus, the brainstem, and the insula (p amygdala and the thalamus, the hypothalamus, and the peristriate cortex (p amygdala connectivity associated with preterm birth. Functional connectivity from the amygdala to other subcortical regions is decreased in preterm neonates compared to term controls. In addition, these data, for the first time, suggest that prenatal stress exposure amplifies these decreases.

  18. Alteration of 99mTc-DMSA biodistribution in glomerulonephritis

    International Nuclear Information System (INIS)

    Rajic, M.; Bogicevic, M.; Ilic, S.; Vlajkovic, M.; Antic, S.; Mitic, B.; Avramovic, M.; Mitic-Zlatovic, M.; Stefanovic, V.

    2002-01-01

    The aim of this study was to assess the relation between 99T c-DMSA biodistribution and its reliability as a marker of renal function in patients with glomerular kidney diseases. Sixty-seven patients involved in this study were classified into two groups according to 99T c-DTPA clearance and serum creatinine values: the 1. group consisted of 42 patients without renal failure while the 2nd group included 25 patients with renal failure. 99T c-DMSA biodistribution was determined by measuring kidney, blood and urine activity at 2 h and 4 h. The results, compared with those of 23 healthy volunteers, indicated the quantitative alteration of 99T c-DMSA distribution in both glomerulonephritis patient groups. In reference to the control mean values of 2 h and 4 h, in patients without renal failure, kidney activity was found decreased to 52% and 57%, while the blood activity increase of 37% and 44% was recorded together with the urine activity increase of 38% and 23%. In patients with renal failure the alterations of renal and blood activity were more remarkable, but the urine loss was found to be unchanged. It is suggested that these biodistribution changes originate mainly from tubular impairment. However, in glomerulonephritis patients, altered glomerular filtration might considerably affect biodistribution of this radiopharmaceutical and limits its suitability for precise quantitative estimation of renal function. (author)

  19. Frequency of psychological alterations in primary antiphospholipid syndrome: preliminary study.

    Science.gov (United States)

    Sadetski, M; Tourinho Moretto, M L; Correia de Araujo, R P; de Carvalho, J F

    2018-04-01

    Objectives To detect the frequency of psychological alterations in primary antiphospholipid syndrome patients. Methods Thirty-six primary antiphospholipid syndrome patients were analyzed by a psychological interview using a standard protocol and review of medical charts. Clinical manifestations, associated comorbidities, antiphospholipid antibodies, and treatment were also evaluated. Results The mean age was 44.2 ± 10.8 years, 29 (80%) were women and 29 (80%) were of Caucasian race. The mean duration of disease was 7.3 ± 5.2 years. The frequency of the presence of psychological alterations was 97.1%. Family dependence was observed in 14 (40%), memory loss in 12 (34.3%), social losses in 12 (34.3%), sexual limitations in seven (20%), sadness in six (17.1%), severe speech limitation in four (11.4%), anxiety in three (8.6%), learning difficulty in two (5.7%), generalized phobia in two (5.7%), suicide ideation in one (2.6%), agoraphobia in one (2.6%), and obsessive-compulsive disorder in one (2.6%). Conclusion This study demonstrated that almost all primary antiphospholipid syndrome patients have psychological alterations. These data reinforce the need for psychological evaluation in primary antiphospholipid syndrome patients.

  20. Repeated swim stress alters brain benzodiazepine receptors measured in vivo

    Energy Technology Data Exchange (ETDEWEB)

    Weizman, R.; Weizman, A.; Kook, K.A.; Vocci, F.; Deutsch, S.I.; Paul, S.M.

    1989-06-01

    The effects of repeated swim stress on brain benzodiazepine receptors were examined in the mouse using both an in vivo and in vitro binding method. Specific in vivo binding of (/sup 3/H)Ro15-1788 to benzodiazepine receptors was decreased in the hippocampus, cerebral cortex, hypothalamus, midbrain and striatum after repeated swim stress (7 consecutive days of daily swim stress) when compared to nonstressed mice. In vivo benzodiazepine receptor binding was unaltered after repeated swim stress in the cerebellum and pons medulla. The stress-induced reduction in in vivo benzodiazepine receptor binding did not appear to be due to altered cerebral blood flow or to an alteration in benzodiazepine metabolism or biodistribution because there was no difference in (14C)iodoantipyrine distribution or whole brain concentrations of clonazepam after repeated swim stress. Saturation binding experiments revealed a change in both apparent maximal binding capacity and affinity after repeated swim stress. Moreover, a reduction in clonazepam's anticonvulsant potency was also observed after repeated swim stress (an increase in the ED50 dose for protection against pentylenetetrazol-induced seizures), although there was no difference in pentylenetetrazol-induced seizure threshold between the two groups. In contrast to the results obtained in vivo, no change in benzodiazepine receptor binding kinetics was observed using the in vitro binding method. These data suggest that environmental stress can alter the binding parameters of the benzodiazepine receptor and that the in vivo and in vitro binding methods can yield substantially different results.

  1. [Vascular disruption birth defects are not associated to chromosomal alterations].

    Science.gov (United States)

    Pachajoa, Harry; Ariza, Yoseth; Isaza, Carolina; Méndez, Fabián

    2015-11-01

    It is estimated that 2 to 35 of newborns present a congenital malformation. Some publications suggest that vascular disruption birth defects are not associated with chromosomal alterations detected by conventional karyotype. to determine the frequency of chromosomal alterations detected by high resolution G banded karyotype in patients with vascular disruption birth defects in a Colombian population (South America). transversal study. Population: a sample of patients identified by an epidemiological surveillance system of congenital malformations in a reference hospital in Cali, Colombia. 41 cases of vascular disruption birth defects were identified during a 36 month period; in a descending order those were: transverse reduction defects, hydranencephaly and gastroschisis. Two expert cytogenetists performed independent evaluation of the genetic material of the patients, and no chromosomal alterations detectable by G banded karyotype were identified. It is recommended that genetic counseling in cases of defects by vascular disruption is carried out taking into account the empirical recurrence risks reported for each one the types of defects by vascular disruption and the use of karyotype should be limited to cases with other malformations or chromosomal abnormality suspected by phenotype.

  2. The leaf phenophase of deciduous species altered by land pavements

    Science.gov (United States)

    Chen, Yuanyuan; Wang, Xiaoke; Jiang, Bo; Li, Li

    2018-02-01

    It has been widely reported that the urban environment alters leaf and flowering phenophases; however, it remains unclear if land pavement is correlated with these alterations. In this paper, two popular deciduous urban trees in northern China, ash (Fraxinus chinensis) and maple (Acer truncatum), were planted in pervious and impervious pavements at three spacings (0.5 m × 0.5 m, 1.0 m × 1.0 m, and 2.0 m × 2.0 m apart). The beginning and end dates of the processes of leaf budburst and senescence were recorded in spring and fall of 2015, respectively. The results show that leaf budburst and senescence were significantly advanced in pavement compared to non-pavement lands. The date of full leaf budburst was earlier by 0.7-9.3 days for ash and by 0.3-2.3 days for maple under pavements than non-pavements, respectively. As tree spacing increases, the advanced days of leaf budburst became longer. Our results clearly indicate that alteration of leaf phenophases is attributed to land pavement, which should be taken into consideration in urban planning and urban plant management.

  3. Nociceptive Alteration by High Sucrose Diet in Hypoestrogenic Wistar Rats.

    Science.gov (United States)

    Jaramillo-Morales, Osmar Antonio; Espinosa-Juárez, Josué Vidal; Corona-Ramos, Janette Nallely; López-Muñoz, Francisco Javier

    2016-08-01

    Preclinical Research Obesity is a risk factor associated with alterations in pain perception. The aim of this study was to analyse a time-course of nociceptive responses (plantar test) in hypoestrogenic rats after the induction of obesity. Animals (hypoestrogenic and naïve) received either a hypercaloric or regular diet for 24 weeks. Thermal nociception and body weight were measured during this period. At the 4th and 17th weeks after treatment, oral glucose tolerance, blood insulin levels, abdominal fat weight, and uric acid levels were measured. The hypoestrogenic rats on a high sucrose diet had higher body weight and abdominal fat weight than control rats. A biphasic response was observed in the ovariectomized group fed with sucrose with thermal latency being decreased in the fourth week. During weeks 12-18, thermal latency increased compared to that of the hypoestrogenic control. There were no differences in basal blood glucose levels at the 4th and 17th weeks; however, oral glucose tolerance, insulin, and uric acid levels were altered. This indicated that increased body weight and fat as well as alteration sin glucose tolerance, hyperinsulinemia and hyperuricemia, may be associated with the biphasic nociceptive response. Drug Dev Res 77 : 258-266, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  4. Olanzapine Overdose in a Pin Point Pupil with Altered Sensorium

    Directory of Open Access Journals (Sweden)

    Naresh Midha

    2017-09-01

    Full Text Available Background:Olanzapine is a highly tolerable and easily affordable atypical antipsychotic drug which has been commonly prescribed in both inpatient and outpatient settings for several mental disorders. Olanzapine overdose is commonly seen in psychiatric patients, who attempt suicide by intoxicating themselves with their own prescribed medications. Increased olanzapine use is associated with increased incidence of overdosing. Case Presentation:We are reporting a case of olanzapine overdosage as a cause of pinpoint pupils and altered sensorium with exclusion of other differentials. The mainstay of managementof olanzapine overdose is general supportive and symptomatic measures. Discussion: Pinpoint pupils with altered sensorium and agitation are always an alarming situation for a clinician, because of differentials like organophosphorus poisoning, pontine hemorrhage and opium overdosing. Due to olanzapine overdosage, similar clinical picture can be confusing in the emergency department and early identification of such cases is helpful to decrease the risk of fatality. Conclusion: This case highlights the significance of olanzapine overdosing as a differential diagnosis for patients presented with altered sensorium and pinpoint pupils in the emergency department. Olanzapine overdosage is associated with high morbidity and mortality. Although there is no specific antidote for olanzapine overdose, appropriate history, assessment and early diagnosis are very useful for the better outcome.

  5. Mangrove microclimates alter seedling dynamics at the range edge.

    Science.gov (United States)

    Devaney, John L; Lehmann, Michael; Feller, Ilka C; Parker, John D

    2017-10-01

    Recent climate warming has led to asynchronous species migrations, with major consequences for ecosystems worldwide. In woody communities, localized microclimates have the potential to create feedback mechanisms that can alter the rate of species range shifts attributed to macroclimate drivers alone. Mangrove encroachment into saltmarsh in many areas is driven by a reduction in freeze events, and this encroachment can further modify local climate, but the subsequent impacts on mangrove seedling dynamics are unknown. We monitored microclimate conditions beneath mangrove canopies and adjacent open saltmarsh at a freeze-sensitive mangrove-saltmarsh ecotone and assessed survival of experimentally transplanted mangrove seedlings. Mangrove canopies buffered night time cooling during the winter, leading to interspecific differences in freeze damage on mangrove seedlings. However, mangrove canopies also altered biotic interactions. Herbivore damage was higher under canopies, leading to greater mangrove seedling mortality beneath canopies relative to saltmarsh. While warming-induced expansion of mangroves can lead to positive microclimate feedbacks, simultaneous fluctuations in biotic drivers can also alter seedling dynamics. Thus, climate change can drive divergent feedback mechanisms through both abiotic and biotic channels, highlighting the importance of vegetation-microclimate interactions as important moderators of climate driven range shifts. © 2017 by the Ecological Society of America.

  6. Prolonged morphine administration alters protein expression in the rat myocardium

    Directory of Open Access Journals (Sweden)

    Drastichova Zdenka

    2011-11-01

    Full Text Available Abstract Background Morphine is used in clinical practice as a highly effective painkiller as well as the drug of choice for treatment of certain heart diseases. However, there is lack of information about its effect on protein expression in the heart. Therefore, here we aimed to identify the presumed alterations in rat myocardial protein levels after prolonged morphine treatment. Methods Morphine was administered to adult male Wistar rats in high doses (10 mg/kg per day for 10 days. Proteins from the plasma membrane- and mitochondria-enriched fractions or cytosolic proteins isolated from left ventricles were run on 2D gel electrophoresis, scanned and quantified with specific software to reveal differentially expressed proteins. Results Nine proteins were found to show markedly altered expression levels in samples from morphine-treaded rats and these proteins were identified by mass spectrometric analysis. They belong to different cell pathways including signaling, cytoprotective, and structural elements. Conclusions The present identification of several important myocardial proteins altered by prolonged morphine treatment points to global effects of this drug on heart tissue. These findings represent an initial step toward a more complex view on the action of morphine on the heart.

  7. Interventions in the Alteration on Lingual Frenum: Systematic Review

    Science.gov (United States)

    Miranda, Priscilla Poliseni; Cardoso, Carolina Louise; Gomes, Erissandra

    2015-01-01

    Introduction  Altered lingual frenum modifies the normal tongue mobility, which may influence the stomatognathic functions, resulting in anatomical, physiological and social damage to the subject. It is necessary that health professionals are aware of the process of evaluation, diagnostics and treatment used today, guiding their intervention. Objective  To perform a systematic review of what are the treatment methods used in cases of lingual frenum alteration. Data Synthesis  The literature searches were conducted in MEDLINE, LILACS, SciELO, Cochrane and IBECS, delimited by language (Portuguese, English, Spanish), date of publication (January 2000 to January 2014) and studies performed in humans. The selection order used to verify the eligibility of the studies were related to: full text availability; review the abstract; text analysis; final selection. Of the total 443 publications, 26 remained for analysis. The surgical approach was used in all studies, regardless of the study population (infants, children and adults), with a range of tools and techniques employed; speech therapy was recommended in the post surgical in 4 studies. Only 4 studies, all with infants, showed scientific evidence. Conclusion  Surgical intervention is effective for the remission of the limitations caused by the alteration on lingual frenum, but there is a deficit of studies with higher methodological quality. The benefits of speech therapy in the post surgical period are described from improvement in the language of mobility aspects and speech articulation. PMID:27413412

  8. Central pain processing is altered in people with Achilles tendinopathy.

    Science.gov (United States)

    Tompra, Nefeli; van Dieën, Jaap H; Coppieters, Michel W

    2016-08-01

    Tendinopathy is often a chronic condition. The mechanisms behind persistent tendon pain are not yet fully understood. It is unknown whether, similar to other persistent pain states, central pain mechanisms contribute to ongoing tendon pain. We investigated the presence of altered central pain processing in Achilles tendinopathy by assessing the conditioned pain modulation (CPM) effect in people with and without Achilles tendinopathy. 20 people with Achilles tendinopathy and 23 healthy volunteers participated in this cross-sectional study. CPM was assessed by the cold pressor test. The pressure pain threshold (PPT) was recorded over the Achilles tendon before and during immersion of the participant's hand into cold water. The CPM effect was quantified as the absolute difference in PPT before and during the cold pressor test. An increase in PPT was observed in the Achilles tendinopathy and control group during the cold pressor test (ptendinopathy group (mean difference=36.4 kPa, SD=68.1 kPa; ptendinopathy compared to people without Achilles tendinopathy. A reduced conditioned pain modulation effect reflects altered central pain processing which is believed to contribute to the persistence of pain in other conditions. Altered central pain processing may also be an important factor in persistent tendon pain that has traditionally been regarded to be dominated by peripheral mechanisms. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

  9. Growth and alteration of uranium-rich microlite

    International Nuclear Information System (INIS)

    Giere, R.; Swope, R. J.; Buck, E. C.; Guggenheim, R.; Mathys, D.; Reusser, E.

    2000-01-01

    Uranium-rich microlite, a pyrochlore-group mineral, occurs in 440 Ma old lithium pegmatites of the Mozambique Belt in East Africa. Microlite exhibits a pronounced growth zoning, with a U-free core surrounded by a U-rich rim (UO 2 up to 17 wt.%). The core exhibits conjugate sets of straight cracks (cleavage planes) which provided pathways for a late-stage U-enriched pegmatitic fluid which interacted with the U-free microlite to produce a distinct U enrichment along the cracks and led to the formation of the U-rich rim. Following the stage of U incorporation into microlite, a second generation of hydrothermal fluids deposited mica along the cleavage planes. Subsequent to these two hydrothermal stages, the host rock was uplifted and subjected to intense low-temperature alteration during which Na, Ca and F were leached from the microlite crystals. This alteration also led to a hydration of microlite, but there is no evidence of U loss. These low-temperature alteration effects were only observed in the U-rich rim which is characterized by a large number of irregular cracks which are most probably the result of metamictization, as indicated by electron diffraction images and powder X-ray patterns. The pyrochlore-group minerals provide excellent natural analogues for pyrochlore-based nuclear waste forms, because samples of variable age and with high actinide contents are available

  10. Ocean acidification alters predator behaviour and reduces predation rate.

    Science.gov (United States)

    Watson, Sue-Ann; Fields, Jennifer B; Munday, Philip L

    2017-02-01

    Ocean acidification poses a range of threats to marine invertebrates; however, the emerging and likely widespread effects of rising carbon dioxide (CO 2 ) levels on marine invertebrate behaviour are still little understood. Here, we show that ocean acidification alters and impairs key ecological behaviours of the predatory cone snail Conus marmoreus Projected near-future seawater CO 2 levels (975 µatm) increased activity in this coral reef molluscivore more than threefold (from less than 4 to more than 12 mm min -1 ) and decreased the time spent buried to less than one-third when compared with the present-day control conditions (390 µatm). Despite increasing activity, elevated CO 2 reduced predation rate during predator-prey interactions with control-treated humpbacked conch, Gibberulus gibberulus gibbosus; 60% of control predators successfully captured and consumed their prey, compared with only 10% of elevated CO 2 predators. The alteration of key ecological behaviours of predatory invertebrates by near-future ocean acidification could have potentially far-reaching implications for predator-prey interactions and trophic dynamics in marine ecosystems. Combined evidence that the behaviours of both species in this predator-prey relationship are altered by elevated CO 2 suggests food web interactions and ecosystem structure will become increasingly difficult to predict as ocean acidification advances over coming decades. © 2017 The Author(s).

  11. Repeated swim stress alters brain benzodiazepine receptors measured in vivo

    International Nuclear Information System (INIS)

    Weizman, R.; Weizman, A.; Kook, K.A.; Vocci, F.; Deutsch, S.I.; Paul, S.M.

    1989-01-01

    The effects of repeated swim stress on brain benzodiazepine receptors were examined in the mouse using both an in vivo and in vitro binding method. Specific in vivo binding of [ 3 H]Ro15-1788 to benzodiazepine receptors was decreased in the hippocampus, cerebral cortex, hypothalamus, midbrain and striatum after repeated swim stress (7 consecutive days of daily swim stress) when compared to nonstressed mice. In vivo benzodiazepine receptor binding was unaltered after repeated swim stress in the cerebellum and pons medulla. The stress-induced reduction in in vivo benzodiazepine receptor binding did not appear to be due to altered cerebral blood flow or to an alteration in benzodiazepine metabolism or biodistribution because there was no difference in [14C]iodoantipyrine distribution or whole brain concentrations of clonazepam after repeated swim stress. Saturation binding experiments revealed a change in both apparent maximal binding capacity and affinity after repeated swim stress. Moreover, a reduction in clonazepam's anticonvulsant potency was also observed after repeated swim stress [an increase in the ED50 dose for protection against pentylenetetrazol-induced seizures], although there was no difference in pentylenetetrazol-induced seizure threshold between the two groups. In contrast to the results obtained in vivo, no change in benzodiazepine receptor binding kinetics was observed using the in vitro binding method. These data suggest that environmental stress can alter the binding parameters of the benzodiazepine receptor and that the in vivo and in vitro binding methods can yield substantially different results

  12. Genetic alterations in head and neck squamous cell carcinomas

    Directory of Open Access Journals (Sweden)

    Nagai M.A.

    1999-01-01

    Full Text Available The genetic alterations observed in head and neck cancer are mainly due to oncogene activation (gain of function mutations and tumor suppressor gene inactivation (loss of function mutations, leading to deregulation of cell proliferation and death. These genetic alterations include gene amplification and overexpression of oncogenes such as myc, erbB-2, EGFR and cyclinD1 and mutations, deletions and hypermethylation leading to p16 and TP53 tumor suppressor gene inactivation. In addition, loss of heterozygosity in several chromosomal regions is frequently observed, suggesting that other tumor suppressor genes not yet identified could be involved in the tumorigenic process of head and neck cancers. The exact temporal sequence of the genetic alterations during head and neck squamous cell carcinoma (HNSCC development and progression has not yet been defined and their diagnostic or prognostic significance is controversial. Advances in the understanding of the molecular basis of head and neck cancer should help in the identification of new markers that could be used for the diagnosis, prognosis and treatment of the disease.

  13. Altered Cortical Ensembles in Mouse Models of Schizophrenia.

    Science.gov (United States)

    Hamm, Jordan P; Peterka, Darcy S; Gogos, Joseph A; Yuste, Rafael

    2017-04-05

    In schizophrenia, brain-wide alterations have been identified at the molecular and cellular levels, yet how these phenomena affect cortical circuit activity remains unclear. We studied two mouse models of schizophrenia-relevant disease processes: chronic ketamine (KET) administration and Df(16)A +/- , modeling 22q11.2 microdeletions, a genetic variant highly penetrant for schizophrenia. Local field potential recordings in visual cortex confirmed gamma-band abnormalities similar to patient studies. Two-photon calcium imaging of local cortical populations revealed in both models a deficit in the reliability of neuronal coactivity patterns (ensembles), which was not a simple consequence of altered single-neuron activity. This effect was present in ongoing and sensory-evoked activity and was not replicated by acute ketamine administration or pharmacogenetic parvalbumin-interneuron suppression. These results are consistent with the hypothesis that schizophrenia is an "attractor" disease and demonstrate that degraded neuronal ensembles are a common consequence of diverse genetic, cellular, and synaptic alterations seen in chronic schizophrenia. Published by Elsevier Inc.

  14. Alteration, fracture infills and weathering of the Strath Halladale granite

    International Nuclear Information System (INIS)

    Storey, B.C.; Lintern, B.C.

    1981-12-01

    The Strath Halladale Granite has undergone a complex history of faulting, alteration and weathering. The alteration varies from thin ramifying veins and irregular diffuse areas within fresh rock to alteration zones in which all the major phases have been partially or completely replaced. Initial reactions were associated with magmatic fluids which formed pegmatites and aplites within extensional fractures. Introduction of meteoric waters resulted in the formation of a convecting hydrothermal system driven by a magmatic heat energy source. The migrating fluids formed secondary dioctahedral micas and chlorite within the granite, and calcite, siderite, iron sulphide, iron oxides, smectites and quartz within the brittle fractures. Many fractures are shear zones which are infilled by granulated quartz, feldspar and mica. The presence of montmorillonite, the lowest temperature mineral phase, and a preliminary study of stable isotopes indicate temperatures in excess of 100 deg C for migrating alkali-rich fluids. In an assessment of the feasibility of the disposal of high level radioactive waste the ubiquitous presence of montmorillonite, which has a high sorption capacity, is important. (author)

  15. Alterations in Nasal Sensibility Following Calcium Hydroxyapatite Dorsal Augmentation.

    Science.gov (United States)

    Alharethy, Sami

    2018-03-01

    There are a many types of filler products that surgeons used for soft tissue augmentation. Soft Tissue Fillers, also known as injectable grafts, is a medical device implants. One of the materials used in soft tissue fillers is calcium hydroxylapatite (CaHA) that is commonly used for treating nasal deformities and nasal reshaping too. Calcium hydroxylapatite is a kind of mineral that can be found in human teeth and bones. It is considered long-lasting but nonpermanent filler and is biocompatible with human tissue. The aim of this study is to measure the alterations in sensibility and patient satisfaction following CaHA filler injection. In a prospective study, 30 patients who underwent CaHA filler injections from January to December 2016 at a Private Tertiary Care Hospital in Riyadh, Saudi Arabia were included. Means and standard deviations were measured for pressure threshold values at each test area preprocedure 2 weeks after procedure (). Alterations between pre and postprocedure values were verified using the match-paired Student t test preprocedures. None of the patients had any subjective sensory symptoms. Majority of patients were extremely satisfied with the results.(Table is included in full-text article.) CONCLUSION:: With correct anatomic knowledge and precise technique in doing the CaHA gel injection procedure, nasal sensibility will not be altered. In addition, injection of CaHA gel can be valuable tool for plastic surgeons to consider for nasal reshaping.

  16. Altered expression of histamine signaling genes in autism spectrum disorder.

    Science.gov (United States)

    Wright, C; Shin, J H; Rajpurohit, A; Deep-Soboslay, A; Collado-Torres, L; Brandon, N J; Hyde, T M; Kleinman, J E; Jaffe, A E; Cross, A J; Weinberger, D R

    2017-05-09

    The histaminergic system (HS) has a critical role in cognition, sleep and other behaviors. Although not well studied in autism spectrum disorder (ASD), the HS is implicated in many neurological disorders, some of which share comorbidity with ASD, including Tourette syndrome (TS). Preliminary studies suggest that antagonism of histamine receptors 1-3 reduces symptoms and specific behaviors in ASD patients and relevant animal models. In addition, the HS mediates neuroinflammation, which may be heightened in ASD. Together, this suggests that the HS may also be altered in ASD. Using RNA sequencing (RNA-seq), we investigated genome-wide expression, as well as a focused gene set analysis of key HS genes (HDC, HNMT, HRH1, HRH2, HRH3 and HRH4) in postmortem dorsolateral prefrontal cortex (DLPFC) initially in 13 subjects with ASD and 39 matched controls. At the genome level, eight transcripts were differentially expressed (false discovery rate effect on any of the individual HS genes but expression of the gene set of HNMT, HRH1, HRH2 and HRH3 was significantly altered. Curated HS gene sets were also significantly differentially expressed. Differential expression analysis of these gene sets in an independent RNA-seq ASD data set from DLPFC of 47 additional subjects confirmed these findings. Understanding the physiological relevance of an altered HS may suggest new therapeutic options for the treatment of ASD.

  17. Extracellular matrix alterations in the Peyronie’s disease

    Directory of Open Access Journals (Sweden)

    Marcelo Silva Watanabe

    2017-07-01

    Full Text Available Peyronie’s disease is characterized by fibrous plaque formation of the tunica albuginea, causing penile deformity and fertility problems. The aim of the present study was to investigate alterations in the extracellular matrix in Peyronie’s disease. The study used tissues collected by surgical procedure from individuals that presented a well-established disease, while control samples were obtained by biopsies of fresh cadavers. Immunohistochemistry analysis followed by digital quantification was performed to evaluate TGF-β, heparanases and metalloproteinases (MMPs. The profile of sulfated glycosaminoglycans, chondroitin sulfate and dermatan sulfate was determined by agarose gel electrophoresis, while hyaluronic acid quantification was obtained by an ELISA-like assay. The expression of mRNA was investigated for syndecan-1 proteoglycan (Syn-1, interleukine-6 (IL-6, hyaluronic acid synthases, and hyaluronidases. Pathologic features showed decreased apoptosis and blood vessel number in Peyronie’s tissues. TGF-β and IL-6 were significantly enhanced in Peyronie’s disease. There was an increased expression of heparanases, though no alteration was observed for MMPs. Hyaluronic acid as well as hyaluronic acid synthases, hyaluronidases, and dermatan sulfate were not changed, while the level of chondroitin sulfate was significantly (P = 0.008, Mann-Whitney test increased in Peyronie’s samples. Heparanases and sulfated glycosaminoglycans seem to be involved in extracellular matrix alterations in Peyronie’s disease.

  18. The epigenetic alterations of endogenous retroelements in aging.

    Science.gov (United States)

    Cardelli, Maurizio

    2018-02-16

    Endogenous retroelements, transposons that mobilize through RNA intermediates, include some of the most abundant repetitive sequences of the human genome, such as Alu and LINE-1 sequences, and human endogenous retroviruses. Recent discoveries demonstrate that these mobile genetic elements not only act as intragenomic parasites, but also exert regulatory roles in living cells. The risk of genomic instability represented by endogenous retroelements is normally counteracted by a series of epigenetic control mechanisms which include, among the most important, CpG DNA methylation. Indeed, most of the genomic CpG sites subjected to DNA methylation in the nuclear DNA are carried by these repetitive elements. As other parts of the genome, endogenous retroelements and other transposable elements are subjected to deep epigenetic alterations during aging, repeatedly observed in the context of organismal and cellular senescence, in human and other species. This review summarizes the current status of knowledge about the epigenetic alterations occurring in this large, non-genic portion of the genome in aging and age-related conditions, with a focus on the causes and the possible functional consequences of these alterations. Copyright © 2018 Elsevier B.V. All rights reserved.

  19. Aging induced endoplasmic reticulum stress alters sleep and sleep homeostasis.

    Science.gov (United States)

    Brown, Marishka K; Chan, May T; Zimmerman, John E; Pack, Allan I; Jackson, Nicholas E; Naidoo, Nirinjini

    2014-06-01

    Alterations in the quality, quantity, and architecture of baseline and recovery sleep have been shown to occur during aging. Sleep deprivation induces endoplasmic reticular (ER) stress and upregulates a protective signaling pathway termed the unfolded protein response. The effectiveness of the adaptive unfolded protein response is diminished by age. Previously, we showed that endogenous chaperone levels altered recovery sleep in Drosophila melanogaster. We now report that acute administration of the chemical chaperone sodium 4-phenylbutyrate (PBA) reduces ER stress and ameliorates age-associated sleep changes in Drosophila. PBA consolidates both baseline and recovery sleep in aging flies. The behavioral modifications of PBA are linked to its suppression of ER stress. PBA decreased splicing of X-box binding protein 1 and upregulation of phosphorylated elongation initiation factor 2 α, in flies that were subjected to sleep deprivation. We also demonstrate that directly activating ER stress in young flies fragments baseline sleep and alters recovery sleep. Alleviating prolonged or sustained ER stress during aging contributes to sleep consolidation and improves recovery sleep or sleep debt discharge. Copyright © 2014 Elsevier Inc. All rights reserved.

  20. Continuous-time random walks that alter environmental transport properties.

    Science.gov (United States)

    Angstmann, C; Henry, B I

    2011-12-01

    We consider continuous-time random walks (CTRWs) in which the walkers have a finite probability to alter the waiting-time and/or step-length transport properties of their environment, resulting in possibly transient anomalous diffusion. We refer to these CTRWs as transmogrifying continuous-time random walks (TCTRWs) to emphasize that they change the form of the transport properties of their environment, and in a possibly strange way. The particular case in which the CTRW waiting-time density has a finite probability to be permanently altered at a given site, following a visitation by a walker, is considered in detail. Master equations for the probability density function of transmogrifying random walkers are derived, and results are compared with Monte Carlo simulations. An interesting finding is that TCTRWs can generate transient subdiffusion or transient superdiffusion without invoking truncated or tempered power law densities for either the waiting times or the step lengths. The transient subdiffusion or transient superdiffusion arises in TCTRWs with Gaussian step-length densities and exponential waiting-time densities when the altered average waiting time is greater than or less than, respectively, the original average waiting time.

  1. [Cytopathological alterations and risk factors for uterine cervical neoplasm].

    Science.gov (United States)

    de Melo, Simone Cristina Castanho Sabaini; Prates, Letícia; Carvalho, Maria Dalva de Barros; Marcon, Sonia Silva; Pelloso, Sandra Marisa

    2009-12-01

    The aim of the present study was to verify the occurrence of citopathological alterations and risk factors of Uterine Cervical Neoplasm in women attended by SUS--the Public Healthcare System--in a district situated in the North of Paraná State, Brazil from 2001 to 2006. It was a descriptive transversal observational study. The data collection consisted in collection of test results from medical records and interviews. It was achieved 6.356 tests and, 1.02% (65) of the women examined presented alterations. From the tests made 4.869 (70,8%) were from women aged between 25 and 59 years. And 38,5% of the tests presented Cervical Intraepithelial Neoplasm (CIN) I, 32,3% CIN II, 18,5% CIN I and Human Papiloma Virus (HPV). It was interviewed 25 women from the total sample. Most of them presented a risk factor as: smoking habits, sexually transmitted diseases, use of hormonal contraceptive, number of sexual partners, early sexual intercourse. This study concludes that is required educative and more effective actions in order to reduce the alterations, meanly among teenagers.

  2. KARYOTYPE ALTERATIONS AFTER HYBRIDIZATION BETWEEN Pennisetum purpureum AND Pennisetum glaucum

    Directory of Open Access Journals (Sweden)

    Gabriela Barreto dos Reis

    2015-10-01

    Full Text Available ABSTRACTNapier grass and pearl millet are tropical forages from the genus Pennisetum. The variability in those species is explored in breeding programs of forages, as well as in the production of interspecific hybrids. Hybridization is a phenomenon that leads to intergenomic conflicts following the elimination of genomic sequences. In this sense, the present work aimed to study the genomic alterations occurring after interspecific hybridization of pearl millet and Napier grass with the use of cytogenetics and flow cytometry tools. These methods allowed the evaluation of chromosome morphometry, DNA content and genomic ratio in pearl millet, Napier grass and hybrids. It was observed that pearl millet and Napier grass have chromosomes with superposed size. The hybrid presents chromosomes that are smaller than expected, leading to karyotype alterations. Additionally, comparing the DNA content of parents and hybrids, loss of DNA content was demonstrated. Further, changes in the pearl millet and Napier grass genome ratio were also verified in the hybrid nucleus. Moreover, genomic rearrangements were shown to occur through karyotype alterations in the hybrid.

  3. Alterations in white matter pathways in Angelman syndrome.

    Science.gov (United States)

    Peters, Sarika U; Kaufmann, Walter E; Bacino, Carlos A; Anderson, Adam W; Adapa, Pavani; Chu, Zili; Yallampalli, Ragini; Traipe, Elfrides; Hunter, Jill V; Wilde, Elisabeth A

    2011-04-01

    Angelman syndrome is a neurogenetic disorder characterized by severe intellectual disability, absent speech, seizures, and outbursts of laughter. The aim of this study was to utilize diffusion tensor imaging (DTI) to examine alterations in white matter pathways in Angelman syndrome, with an emphasis on correlations with clinical severity. DTI was used to examine the arcuate fasciculus (AF), uncinate fasciculus (UF), inferior longitudinal fasciculus (ILF), inferior fronto-occipital fasciculus (IFOF), and the corpus callosum (CC). We enrolled 14 children aged 8 to 17 years (mean age 10y 8mo; SD 2y 7mo) with Angelman syndrome (seven male; seven female) and 13 typically developing children, aged 8 to 17 years, for comparison (five male; eight female; mean age 12y; SD 2y 9mo). Individuals with Angelman syndrome were assessed using standardized measures of development, language, and behaviour. The children with Angelman syndrome exhibited lower fractional anisotropy and increased radial diffusivity values than the comparison group for the AF, UF, ILF, and CC (p Angelman syndrome had significantly higher apparent diffusion coefficient values in the AF, CC, ILF, and the left IFOF (p Angelman syndrome suggest decreased/delayed myelination, decreased axonal density or diameter, or aberrant axonal organization. Our findings suggest a generalized white matter alteration throughout the brain in those with Angelman syndrome; however, only the alterations in temporal white matter pathways were associated with language and cognitive and social functioning. © The Authors. Journal compilation © Mac Keith Press 2010.

  4. Evolving Human Alteration of the Carbon Cycle: the Watershed Continuum

    Science.gov (United States)

    Kaushal, S.; Delaney Newcomb, K.; Newcomer Johnson, T.; Pennino, M. J.; Smith, R. M.; Beaulieu, J. J.; Belt, K.; Grese, M.; Blomquist, J.; Duan, S.; Findlay, S.; Likens, G.; Mayer, P. M.; Murthy, S.; Utz, R.; Yepsen, M.

    2014-12-01

    Watersheds experiencing land development are constantly evolving, and their biogeochemical signatures are expected to evolve across both space and time in drainage waters. We investigate how land development influences spatial and temporal evolution of the carbon cycle from small streams to major rivers in the Eastern U.S. Along the watershed continuum, we show that there is spatial evolution in: (1) the amount, chemical form, and bioavailability of carbon; (2) carbon retention/release at the reach scale; and (3) ecosystem metabolism of carbon from headwaters to coastal waters. Over shorter time scales, the interaction between land use and climate variability alters magnitude and frequency of carbon "pulses" in watersheds. Amounts and forms of carbon pulses in agricultural and urban watersheds respond similarly to climate variability due to headwater alteration and loss of ecosystem services to buffer runoff and temperature changes. Over longer time scales, land use change has altered organic carbon concentrations in tidal waters of Chesapeake Bay, and there have been increased bicarbonate alkalinity concentrations in rivers throughout the Eastern U.S. due to human activities. In summary, our analyses indicates that the form and reactivity of carbon have evolved over space and time along the watershed continuum with major implications for downstream ecosystem metabolism, biological oxygen demand, carbon dioxide production, and river alkalinization.

  5. Mycorrhizae Alter Toxin Sequestration and Performance of Two Specialist Herbivores

    Directory of Open Access Journals (Sweden)

    Amanda R. Meier

    2018-04-01

    Full Text Available Multitrophic species interactions are shaped by both top-down and bottom-up factors. Belowground symbionts of plants, such as arbuscular mycorrhizal fungi (AMF, can alter the strength of these forces by altering plant phenotype. For example, AMF-mediated changes in foliar toxin and nutrient concentrations may influence herbivore growth and fecundity. In addition, many specialist herbivores sequester toxins from their host plants to resist natural enemies, and the extent of sequestration varies with host plant secondary chemistry. Therefore, by altering plant phenotype, AMF may affect both herbivore performance and their resistance to natural enemies. We examined how inoculation of plants with AMF influences toxin sequestration and performance of two specialist herbivores feeding upon four milkweed species (Asclepias incarnata, A. curassavica, A. latifolia, A. syriaca. We raised aphids (Aphis nerii and caterpillars (Danaus plexippus on plants for 6 days in a fully factorial manipulation of milkweed species and level of AMF inoculation (zero, medium, and high. We then assessed aphid and caterpillar sequestration of toxins (cardenolides and performance, and measured defensive and nutritive traits of control plants. Aphids and caterpillars sequestered higher concentrations of cardenolides from plants inoculated with AMF across all milkweed species. Aphid per capita growth rates and aphid body mass varied non-linearly with increasing AMF inoculum availability; across all milkweed species, aphids had the lowest performance under medium levels of AMF availability and highest performance under high AMF availability. In contrast, caterpillar survival varied strongly with AMF availability in a plant species-specific manner, and caterpillar growth was unaffected by AMF. Inoculation with AMF increased foliar cardenolide concentrations consistently among milkweed species, but altered aboveground biomasses and foliar phosphorous concentrations in a plant

  6. Alteration of granite stone used in building construction

    Directory of Open Access Journals (Sweden)

    Esbert Alemany, R. M.ª

    2007-12-01

    Full Text Available The article contains a synthesis of the different factors involved in the alteration of granite ashlars or cladding used in building construction. Emphasis is placed on the – primarily fissure-like – anisotropies often present in granite, which are usually related to the structural conditions of the quarry where it is mined. Such anisotropies condition the development of certain types of alterations that appear over time, particularly in ashlars. Stone petrography, particularly as regards the chemical composition of the minerals comprising granite, also govern its alteration. Moreover, the commercial term granite often includes other more alkaline rocks generically known as granitoids, whose alterability is higher than in granite per se. The values of some of the physical properties of these rocks, which must be quantified to evaluate their durability, are shown to differ in keeping with their anisotropy. Finally, the forms, causes and mechanisms involved in granite decay are reviewed in the context of its use in building construction.En el artículo se sintetizan los diversos aspectos que inciden en la alteración de las rocas graníticas, cuando estas se utilizan en los edificios, ya sea en forma de sillares o de losetas de revestimiento. Se hace especial hincapié en las anisotropías, fundamentalmente de carácter fisural que suelen presentar los granitos. Estas suelen estar relacionadas con las condiciones estructurales del yacimiento del cual proceden. Dichas anisotropías condicionan el desarrollo de determinadas formas de alteración que con el paso del tiempo se aprecian, sobre todo en los sillares. También se recuerda que la petrografía, y en especial la composición química de los minerales que componen las rocas graníticas, condicionan su alteración, y que dentro del término comercial granito se suelen incluir otras rocas más alcalinas denominadas genéricamente granitoides y más alterables que el granito sensu

  7. Exposure to bisphenol A in young adult mice does not alter ovulation but does alter the fertilization ability of oocytes

    International Nuclear Information System (INIS)

    Moore-Ambriz, Teresita Rocio; Acuña-Hernández, Deyanira Guadalupe; Ramos-Robles, Brenda; Sánchez-Gutiérrez, Manuel; Santacruz-Márquez, Ramsés; Sierra-Santoyo, Adolfo; Piña-Guzmán, Belem

    2015-01-01

    Follicle growth culminates in ovulation, which allows for the expulsion of fertilizable oocytes and the formation of corpora lutea. Bisphenol A (BPA) is present in many consumer products, and it has been suggested that BPA impairs ovulation; however, the underlying mechanisms are unknown. Therefore, this study first evaluated whether BPA alters ovulation by affecting folliculogenesis, the number of corpora lutea or eggs shed to the oviduct, ovarian gonadotropin responsiveness, hormone levels, and estrous cyclicity. Because it has been suggested (but not directly confirmed) that BPA exerts toxic effects on the fertilization ability of oocytes, a second aim was to evaluate whether BPA impacts the oocyte fertilization rate using an in vitro fertilization assay and mating. The possible effects on early zygote development were also examined. Young adult female C57BL/6J mice (39 days old) were orally dosed with corn oil (vehicle) or 50 μg/kg bw/day BPA for a period encompassing the first three reproductive cycles (12–15 days). BPA exposure did not alter any parameters related to ovulation. Moreover, BPA exposure reduced the percentage of fertilized oocytes after either in vitro fertilization or mating, but it did not alter the zygotic stages. The data indicate that exposure to the reference dose of BPA does not impact ovulation but that it does influence the oocyte quality in terms of its fertilization ability. - Highlights: • Bisphenol A targets the fertilization ability of oocytes. • Bisphenol A does not alter ovulation. • Young adult females may be susceptible to the effects of bisphenol A on fertilization.

  8. Reproductive experience does not persistently alter prefrontal cortical-dependent learning but does alter strategy use dependent on estrous phase.

    Science.gov (United States)

    Workman, Joanna L; Crozier, Tamara; Lieblich, Stephanie E; Galea, Liisa A M

    2013-08-01

    Reproductive experiences in females comprise substantial hormonal and experiential changes and can exert long lasting changes in cognitive function, stress physiology, and brain plasticity. The goal of this research was to determine whether prior reproductive experience could alter a prefrontal-cortical dependent form of learning (strategy set shifting) in an operant box. In this study, female Sprague-Dawley rats were mated and mothered once or twice to produce either primiparous or biparous dams, respectively. Age-matched nulliparous controls (reproductively-naïve females with no exposure to pup cues) were also used. Maternal behaviors were also assessed to determine whether these factors would predict cognitive flexibility. For strategy set shifting, rats were trained in a visual-cue discrimination task on the first day and on the following day, were required to switch to a response strategy to obtain a reward. We also investigated a simpler form of behavioral flexibility (reversal learning) in which rats were trained to press a lever on one side of the box the first day, and on the following day, were required to press the opposite lever to obtain a reward. Estrous phase was determined daily after testing. Neither parity nor estrous phase altered total errors or trials to reach criterion in either the set-shifting or reversal-learning tasks, suggesting that PFC-dependent cognitive performance remains largely stable after 1 or 2 reproductive experiences. However, parity and estrous phase interacted to alter the frequency of particular error types, with biparous rats in estrus committing more perseverative but fewer regressive errors during the set-shifting task. This suggests that parity and estrous phase interfere with the ability to disengage from a previously used, but no longer relevant strategy. These data also suggest that parity alters the behavioral sensitivity to ovarian hormones without changing overall performance. Copyright © 2013 Elsevier Inc. All

  9. Altering β-cell number through stable alteration of miR-21 and miR-34a expression

    DEFF Research Database (Denmark)

    Backe, Marie Balslev; Novotny, Guy Wayne; Christensen, Dan Ploug

    2014-01-01

    RNAs, miR-21 and miR-34a, may be involved in mediating cytokine-induced β-cell dysfunction. Therefore, manipulation of miR-21 and miR-34a levels may potentially be beneficial to β cells. To study the effect of long-term alterations of miR-21 or miR-34a levels upon net β-cell number, we stably overexpressed...

  10. Petrography, alteration and genesis of iron mineralization in Roshtkhar

    Directory of Open Access Journals (Sweden)

    Habib Biabangard

    2017-07-01

    Full Text Available Introduction Iron mineralization in Roshtkhar is located in 48 Km east of the city of Roshtkhar and south of the Khorasan Razavi province. It is geologically located in the north east of the Lut block and the Khaf-Bardeskan volcano-plutonic belt. The Khaf-Bardeskan belt is an important metallogenic province since it is a host of valuable ore deposits such as the Kuh-e-Zar Au-Spicularite, the Tanourcheh and the Khaf Iron ore deposits (Karimpour and Malekzadeh Shafaroudi, 2007. Iron and Copper mineralization in this belt are known as the hydrothermal, skarn and IOCG types (Karimpour and Malekzadeh Shafaroudi, 2007. IOCG deposits are a new type of magmatic to hydrothermal mineralization in the continental crust (Hitzman et al., 1992. Precambrian marble, Lower Paleozoic schist and metavolcanics are the oldest rocks of the area. The younger units are Oligocene conglomerate, shale and sandstone, Miocene marl and Quaternary deposits. Iron oxides and Cu sulfides are associated with igneous rocks. Fe and Cu mineralization in Roshtkhar has been subject of a few studies such as Yousefi Surani (2006. This study describes the petrography of the host rocks, ore paragenesis, alteration types, geochemistry, genesis and other features of the Fe and Cu mineralization in the Roshtkhar iron. Methods After detailed field studies and sampling, 30 thin sections and 20 polished sections that were prepared from host rocks and ores were studied by conventional petrographic and mineraloghraphic methods in the geology department of the University of Sistan and Baluchestan. 5 samples from the alteration zones were examined by XRD in the Yamagata University in Japan, and 8 samples from the less altered ones were analyzed by XRF and ICP-OES in the Kharazmi University and the Iranian mineral processing research center (IMPRC in Karaj, respectively. The XRF and ICP-OES data are presented in Table 1. Result and discussion The host rocks of the Roshtkhar Iron deposit are diorite

  11. Exposure to bisphenol A in young adult mice does not alter ovulation but does alter the fertilization ability of oocytes.

    Science.gov (United States)

    Moore-Ambriz, Teresita Rocio; Acuña-Hernández, Deyanira Guadalupe; Ramos-Robles, Brenda; Sánchez-Gutiérrez, Manuel; Santacruz-Márquez, Ramsés; Sierra-Santoyo, Adolfo; Piña-Guzmán, Belem; Shibayama, Mineko; Hernández-Ochoa, Isabel

    2015-12-15

    Follicle growth culminates in ovulation, which allows for the expulsion of fertilizable oocytes and the formation of corpora lutea. Bisphenol A (BPA) is present in many consumer products, and it has been suggested that BPA impairs ovulation; however, the underlying mechanisms are unknown. Therefore, this study first evaluated whether BPA alters ovulation by affecting folliculogenesis, the number of corpora lutea or eggs shed to the oviduct, ovarian gonadotropin responsiveness, hormone levels, and estrous cyclicity. Because it has been suggested (but not directly confirmed) that BPA exerts toxic effects on the fertilization ability of oocytes, a second aim was to evaluate whether BPA impacts the oocyte fertilization rate using an in vitro fertilization assay and mating. The possible effects on early zygote development were also examined. Young adult female C57BL/6J mice (39 days old) were orally dosed with corn oil (vehicle) or 50 μg/kgbw/day BPA for a period encompassing the first three reproductive cycles (12-15 days). BPA exposure did not alter any parameters related to ovulation. Moreover, BPA exposure reduced the percentage of fertilized oocytes after either in vitro fertilization or mating, but it did not alter the zygotic stages. The data indicate that exposure to the reference dose of BPA does not impact ovulation but that it does influence the oocyte quality in terms of its fertilization ability. Copyright © 2015 Elsevier Inc. All rights reserved.

  12. Altered brain network measures in patients with primary writing tremor

    International Nuclear Information System (INIS)

    Lenka, Abhishek; Jhunjhunwala, Ketan Ramakant; Panda, Rajanikant; Saini, Jitender; Bharath, Rose Dawn; Yadav, Ravi; Pal, Pramod Kumar

    2017-01-01

    Primary writing tremor (PWT) is a rare task-specific tremor, which occurs only while writing or while adopting the hand in the writing position. The basic pathophysiology of PWT has not been fully understood. The objective of this study is to explore the alterations in the resting state functional brain connectivity, if any, in patients with PWT using graph theory-based analysis. This prospective case-control study included 10 patients with PWT and 10 age and gender matched healthy controls. All subjects underwent MRI in a 3-Tesla scanner. Several parameters of small-world functional connectivity were compared between patients and healthy controls by using graph theory-based analysis. There were no significant differences in age, handedness (all right handed), gender distribution (all were males), and MMSE scores between the patients and controls. The mean age at presentation of tremor in the patient group was 51.7 ± 8.6 years, and the mean duration of tremor was 3.5 ± 1.9 years. Graph theory-based analysis revealed that patients with PWT had significantly lower clustering coefficient and higher path length compared to healthy controls suggesting alterations in small-world architecture of the brain. The clustering coefficients were lower in PWT patients in left and right medial cerebellum, right dorsolateral prefrontal cortex (DLPFC), and left posterior parietal cortex (PPC). Patients with PWT have significantly altered small-world brain connectivity in bilateral medial cerebellum, right DLPFC, and left PPC. Further studies with larger sample size are required to confirm our results. (orig.)

  13. Altered metabolic signature in pre-diabetic NOD mice.

    Directory of Open Access Journals (Sweden)

    Rasmus Madsen

    Full Text Available Altered metabolism proceeding seroconversion in children progressing to Type 1 diabetes has previously been demonstrated. We tested the hypothesis that non-obese diabetic (NOD mice show a similarly altered metabolic profile compared to C57BL/6 mice. Blood samples from NOD and C57BL/6 female mice was collected at 0, 1, 2, 3, 4, 5, 6, 7, 9, 11, 13 and 15 weeks and the metabolite content was analyzed using GC-MS. Based on the data of 89 identified metabolites OPLS-DA analysis was employed to determine the most discriminative metabolites. In silico analysis of potential involved metabolic enzymes was performed using the dbSNP data base. Already at 0 weeks NOD mice displayed a unique metabolic signature compared to C57BL/6. A shift in the metabolism was observed for both strains the first weeks of life, a pattern that stabilized after 5 weeks of age. Multivariate analysis revealed the most discriminative metabolites, which included inosine and glutamic acid. In silico analysis of the genes in the involved metabolic pathways revealed several SNPs in either regulatory or coding regions, some in previously defined insulin dependent diabetes (Idd regions. Our result shows that NOD mice display an altered metabolic profile that is partly resembling the previously observation made in children progressing to Type 1 diabetes. The level of glutamic acid was one of the most discriminative metabolites in addition to several metabolites in the TCA cycle and nucleic acid components. The in silico analysis indicated that the genes responsible for this reside within previously defined Idd regions.

  14. Tooth alterations in areas of bisphosphonate-induced osteonecrosis.

    Science.gov (United States)

    de Camargo Moraes, Paulo; Silva, Carolina Amália Barcellos; Soares, Andresa Borges; Passador-Santos, Fabrício; Corrêa, Maria Elvira Pizzigatti; de Araújo, Ney Soares; de Araújo, Vera Cavalcanti

    2015-03-01

    Osteonecrosis of the jaw is a potential side effect when using bisphosphonates. Most studies on the effects of bisphosphonates on teeth have been conducted in vitro or in animal models of tooth development. Therefore, the aim of this study was to describe alterations found in human teeth extracted from areas of bisphosphonate-induced osteonecrosis. Using a retrospective study design, 16 teeth from 13 patients were extracted from areas of bisphosphonate-induced osteonecrosis during surgical debridement. The specimens were decalcified and embedded in paraffin. A series of 5-μm sections were prepared, stained with hematoxylin and eosin (H&E) and observed under a light microscope. The majority of the patients were female (53.85 %), with a mean age of 60.23 ± 13.18 years. Zoledronate (IV) was the most common bisphosphonate used (92.3 %), over a mean period of 2 years. The commonest alteration observed was hypercementosis (87.5 %), followed by pulpar necrosis (81.25 %), pulp stones attached to the dentine and loose pulp stones in the pulp chamber and root canals in addition to linear calcifications (68.75 %), dentinoid/osteoid material formation (18.75 %), and dental ankylosis (6.25 %). Patients undergoing bisphosphonate therapy present diverse tooth alterations, which should be closely monitored by clinicians to prevent complications. It is paramount that the teeth involved in oral lesions are always examined. Attention should be drawn to the need to establish preventive measures, in terms of dental treatment, for patients prior to starting bisphosphonate therapy.

  15. Distinct oxylipin alterations in diverse models of cystic kidney diseases.

    Science.gov (United States)

    Monirujjaman, Md; Devassy, Jessay G; Yamaguchi, Tamio; Sidhu, Nikhil; Kugita, Masanori; Gabbs, Melissa; Nagao, Shizuko; Zhou, Jing; Ravandi, Amir; Aukema, Harold M

    2017-12-01

    Cystic kidney diseases are characterized by multiple renal cysts and are the leading cause of inherited renal disease. Oxylipins are bioactive lipids derived from fatty acids formed via cyclooxygenase, lipoxygenase and cytochrome P450 activity, and are important regulators of renal health and disease. Oxylipins are altered in nephronophthisis, a type of cystic kidney disease. To further investigate and to determine whether other cystic renal diseases share these abnormalities, a targeted lipidomic analysis of renal oxylipins was performed in orthologous models of autosomal dominant polycystic kidney disease 1 (Mx1Cre + Pkd1 flox/flox mouse) and 2 (Pkd2 ws25/- mouse), autosomal recessive polycystic kidney disease (PCK rat) and nephronophthisis (jck/jck mouse). Kidney cyclooxygenase oxylipins were consistently higher in all diseased kidneys, even in very early stage disease. On the other hand, cytochrome P450 epoxygenase derived oxylipins were lower only in the autosomal recessive polycystic kidney disease and nephronophthisis models, while lipoxygenase and cytochrome P450 hydroxylase derived oxylipins were lower only in nephronophthisis. Sex effects on renal oxylipin alterations were observed but they did not always coincide with sex effects on disease. For oxylipins with sex effects, arachidonic acid derived oxylipins formed via cyclooxygenases and lipoxygenases were higher in females, while oxylipins from other fatty acids and via cytochrome P450 enzymes were higher in males. The consistent and unique patterns of oxylipin alterations in the different models indicates the importance of these bioactive lipids in cystic renal diseases, suggesting that pharmacological agents (e.g. cyclooxygenase inhibitors) may be useful in treating these disorders, for which effective treatment remains elusive. Copyright © 2017 Elsevier B.V. All rights reserved.

  16. Uranium-induced sensory alterations in the zebrafish Danio rerio

    Energy Technology Data Exchange (ETDEWEB)

    Faucher, K., E-mail: kfaucher@hotmail.fr [Laboratoire d' ecotoxicologie des radionucleides (LECO), Institut de Radioprotection et Surete Nucleaire, Centre de Cadarache, Batiment 186, BP3, 13115 Saint Paul lez Durance (France); Floriani, M.; Gilbin, R.; Adam-Guillermin, C. [Laboratoire d' ecotoxicologie des radionucleides (LECO), Institut de Radioprotection et Surete Nucleaire, Centre de Cadarache, Batiment 186, BP3, 13115 Saint Paul lez Durance (France)

    2012-11-15

    The effect of chronic exposure to uranium ions (UO{sub 2}{sup 2+}) on sensory tissues including the olfactory and lateral line systems was investigated in zebrafish (Danio rerio) using scanning electron microscopy. The aim of this study was to determine whether exposure to uranium damaged sensory tissues in fish. The fish were exposed to uranium at the concentration of 250 {mu}g l{sup -1} for 10 days followed by a depuration period of 23 days. Measurements of uranium uptake in different fish organs: olfactory rosettes and bulbs, brain, skin, and muscles, were also determined by ICP-AES and ICP-MS during the entire experimental period. The results showed that uranium displayed a strong affinity for sensory structures in direct contact with the surrounding medium, such as the olfactory and lateral line systems distributed on the skin. A decreasing gradient of uranium concentration was found: olfactory rosettes > olfactory bulbs > skin > muscles > brain. At the end of the experiment, uranium was present in non-negligible quantities in sensory tissues. In parallel, fish exposed to uranium showed severe sensory tissue alterations at the level of the olfactory and lateral line systems. In both sensory systems, the gross morphology was altered and the sensory hair cells were significantly damaged very early after the initiation of exposure (from the 3rd day). At the end of the experiment, after 23 days of depuration, the lateral line system still displayed slight tissue alterations, but approximately 80% of the neuromasts in this system had regenerated. In contrast, the olfactory system took more time to recover, as more than half of the olfactory rosettes observed remained destroyed at the end of the experiment. This study showed, for the first time, that uranium is able to damage fish sensory tissues to such an extent that tissue regeneration is delayed.

  17. Supplemental feeding alters migration of a temperate ungulate

    Science.gov (United States)

    Jones, Jennifer D; Kauffman, Matthew J.; Monteith, Kevin L.; Scurlock, Brandon M.; Albeke, Shannon E.; Cross, Paul C.

    2014-01-01

    Conservation of migration requires information on behavior and environmental determinants. The spatial distribution of forage resources, which migration exploits, often are altered and may have subtle, unintended consequences. Supplemental feeding is a common management practice, particularly for ungulates in North America and Europe, and carryover effects on behavior of this anthropogenic manipulation of forage are expected in theory, but have received limited empirical evaluation, particularly regarding effects on migration. We used global positioning system (GPS) data to evaluate the influence of winter feeding on migration behavior of 219 adult female elk (Cervus elaphus) from 18 fed ranges and 4 unfed ranges in western Wyoming. Principal component analysis revealed that the migratory behavior of fed and unfed elk differed in distance migrated, and the timing of arrival to, duration on, and departure from summer range. Fed elk migrated 19.2 km less, spent 11 more days on stopover sites, arrived to summer range 5 days later, resided on summer range 26 fewer days, and departed in the autumn 10 days earlier than unfed elk. Time-to-event models indicated that differences in migratory behavior between fed and unfed elk were caused by altered sensitivity to the environmental drivers of migration. In spring, unfed elk migrated following plant green-up closely, whereas fed elk departed the feedground but lingered on transitional range, thereby delaying their arrival to summer range. In autumn, fed elk were more responsive to low temperatures and precipitation events, causing earlier departure from summer range than unfed elk. Overall, supplemental feeding disconnected migration by fed elk from spring green-up and decreased time spent on summer range, thereby reducing access to quality forage. Our findings suggest that ungulate migration can be substantially altered by changes to the spatial distribution of resources, including those of anthropogenic origin, and that

  18. Alteration mechanisms of UOX spent fuel under water

    International Nuclear Information System (INIS)

    Muzeau, B.

    2008-06-01

    The mechanisms of spent fuel alteration in aqueous media need to be understood on the assumption of a direct disposal of the assemblies in a geological formation or for long duration storage in pool. This work is a contribution to the study of the effects of the alpha and/or beta/gamma radiolysis of water on the oxidation and the dissolution of the UO 2 matrix of UOX spent fuel. The effects of the alpha radiolysis, predominant in geological disposal conditions, were quantified by using samples of UO 2 doped with plutonium. The leaching experiments highlighted two types of control for the matrix alteration according to the alpha activity. The first is based on the radiolytic oxidation of the surface and leads to a continuous release of uranium in solution whereas the second is based on a control by the solubility of uranium. An activity threshold, between 18 MBq.g -1 and 33 MBq.g -1 , was defined in a carbonated water. The value of this threshold is dependent on the experimental conditions and the presence or not of electro-active species such as hydrogen in the system. The effects of the alpha/beta/gamma radiolysis in relation with the storage conditions were also quantified. The experimental data obtained on spent fuel indicate that the alteration rate of the matrix based on the behaviour of tracer elements (caesium and strontium) reached a maximum value of some mg.m -2 .d -1 , even under very oxidizing conditions. The solubility of uranium and the nature of the secondary phases depend however on the extent of the oxidizing conditions. (author)

  19. REPEATED ACUTE STRESS INDUCED ALTERATIONS IN CARBOHYDRATE METABOLISM IN RAT

    Directory of Open Access Journals (Sweden)

    Nirupama R.

    2010-09-01

    Full Text Available Acute stress induced alterations in the activity levels of rate limiting enzymes and concentration of intermediates of different pathways of carbohydrate metabolism have been studied. Adult male Wistar rats were restrained (RS for 1 h and after an interval of 4 h they were subjected to forced swimming (FS exercise and appropriate controls were maintained. Five rats were killed before the commencement of the experiment (initial controls, 5 control and equal number of stressed rats were killed 2 h after RS and remaining 5 rats in each group were killed 4 h after FS. There was a significant increase in the adrenal 3β- hydroxy steroid dehydrogenase activity following RS, which showed further increase after FS compared to controls and thereby indicated stress response of rats. There was a significant increase in the blood glucose levels following RS which showed further increase and reached hyperglycemic condition after FS. The hyperglycemic condition due to stress was accompanied by significant increases in the activities of glutamate- pyruvate transaminase, glutamate- oxaloacetate transaminase, glucose -6- phosphatase and lactate dehydrogenase and significant decrease in the glucose -6- phosphate dehydrogenase and pyruvate dehydrogenase activities, whereas pyruvate kinase activity did not show any alteration compared to controls. Further, the glycogen and total protein contents of the liver were decreased whereas those of pyruvate and lactate showed significant increase compared to controls after RS as well as FS.The results put together indicate that acute stress induced hyperglycemia results due to increased gluconeogenesis and glycogenolysis without alteration in glycolysis. The study first time reveals that after first acute stress exposure, the subsequent stressful experience augments metabolic stress response leading to hyperglycemia. The results have relevance to human health as human beings are exposed to several stressors in a day and

  20. [Psychological alterations in patients with adult celiac disease].

    Science.gov (United States)

    Martínez Cerezo, Francisco J; Castillejo, Gemma; Guillen, Núria; Morente, Vanessa; Simó, Josep M; Tena, Francisco J; Marsal, Joan; Pascual, Domingo

    2014-04-01

    Patients with recently-diagnosed adult celiac disease were evaluated with the Gastrointestinal Symptom rating Scale (GSRS) and Psychological General Well-Being Index (PGWBI) to evaluate their psychological alterations, the association between any alterations and gastrointestinal symptoms, and their outcome after starting a gluten-free diet. The patients underwent nutritional assessment and then started a gluten-free diet; they were reassessed 6 months later. Quantitative variables are expressed as the median and 25th-75th percentiles. We included 21 patients, 17 women and 4 mena, with a mean age of 43 years (31-47). The results of histological analysis were compatible with Marsh I lesions in 6 patients, Marsh IIIa in 6 and Marsh IIIb in 9. At baseline, 8 patients showed severe psychological distress, 4 showed moderate distress and 9 showed no distress. The GSRS score was 34 (17-43) and the PGWBI was 64 (48-87), with a significant correlation between the 2 indexes (rho=-.58, P=.006). At 6 months, 3 patients had severe psychological distress, 5 had moderate distress, 9 showed no distress and 4 showed psychological well-being. The GSRS score at 6 months was 13 (8-17) and the PGWBI was 83 (68-95) (P<.05 compared with baseline data for the 3 indicators). The 6 axes of the PGWBI showed significant improvement. At 6 months, no correlation was found between the GSRS and PGWBI. Patients with celiac disease have psychological alterations whose intensity is related to gastrointestinal symptoms. These symptoms improve after the start of a gluten-free diet. Copyright © 2013 Elsevier España, S.L. and AEEH y AEG. All rights reserved.