Sample records for earth une ombrelle

  1. Une masse palpébrale révélant une fistule carotidocaverneuse

    PubMed Central

    Oulali, Noureddine; Moufid, Fayçal; Khoulali, Mohammed; Sekhsoukh, Rachid; Housni, Brahim; Ghailan, Mohamed Rachid

    2012-01-01

    Les auteurs rapportent une observation particulière, chez un homme de 48 ans ayant dans ces antécédents un traumatisme crânio-faciale grave il y'a dix ans, qui présente depuis huit mois une masse palpébrale droite, avec une discrète exophtalmie et hémorragie sous conjonctivale, l'angio IRM a permis de confirmer le diagnostique d'une fistule carotidocaverneuse à haut débit, qui est responsable de cette symptomatologie. L'objectif de cet article est de mettre la lumière sur cette pathologie rare, en insistant sur les particularités cliniques de présentation d'une part, et sur le plan thérapeutique d'autre part, en exposant l'intérêt de la radiologie interventionnelle. PMID:23330040

  2. Maladie de Takayasu et polyarthrite rhumatoïde: une association rare - à propos d'une observation

    PubMed Central

    Frikha, Faten; Maazoun, Fatma; Snoussi, Mouna; Abid, Leila; Abid, Hanen; Bouassida, Walid; Kaddour, Neila; Bahloul, Zouhir

    2012-01-01

    L'artérite de Takayasu ou maladie de Takayasu (MT) et la polyarthrite rhumatoïde (PR) et sont deux maladies inflammatoires chroniques et leur association a été rapportée dans la littérature à travers quelques observations de cas sporadiques. Nous rapportons une nouvelle observation d'une telle association. Une patiente âgée de 44 ans, diagnostiquée avec une polyarthrite rhumatoïde à facteur rhumatoïde positif, qui a développé des céphalées avec des vertiges de caractère permanent. L'examen révélait un pouls radial et huméral abolis à droite, un souffle carotidien bilatéral et une tension artérielle imprenable à droite. L'artériographie a confirmé la présence d'une atteinte de l'arc aortique type MT. Le diagnostic d'une maladie de Takayasu associée à une polyarthrite rhumatoïde était retenu. La patiente était traitée par une corticothérapie (prednisone à la dose de 0,5 mg/kg par jour) et un traitement de fond par Méthotrexate avec une bonne réponse initiale. A travers notre observation et une revue de la littérature, les caractéristiques épidémiologiques, étiopathogéniques, cliniques, thérapeutiques et évolutives de cette association seront discutées. PMID:22937201

  3. Une rare cause de sciatique non discale: une polyarthrite rhumatoïde

    PubMed Central

    Akasbi, Nessrine; Abourazzak, Fatima Ezzahra; Harzy, Taoufik

    2014-01-01

    La polyarthrite rhumatoïde est le rhumatisme inflammatoire chronique le plus fréquent. Ses complications neurologiques sont dominées par les neuropathies périphériques, cliniquement asymptomatiques, mais peuvent être détectées sur l’électromyogramme (EMG). Nous rapportons l'observation d'une patiente qui a présenté une neuropathie sensitivo-motrice aux deux membres inférieurs associée à une sciatique de topographie L5 d'origine rhumatoïde. PMID:25709734

  4. Developpement d'une commande pour une hydrolienne de riviere et optimisation =

    NASA Astrophysics Data System (ADS)

    Tetrault, Philippe

    Suivant le developpement des energies renouvelables, la presente etude se veut une base theorique quant aux principes fondamentaux necessaires au bon fonctionnement et a l'implementation d'une hydrolienne de riviere. La problematique derriere ce nouveau type d'appareil est d'abord presentee. La machine electrique utilisee dans l'application, c'est-a-dire la machine synchrone a aimants permanents, est etudiee : ses equations dynamiques mecaniques et electriques sont developpees, introduisant en meme temps le concept de referentiel tournant. Le fonctionnement de l'onduleur utilise, soit un montage en pont complet a deux niveaux a semi-conducteurs, est explique et mit en equation pour permettre de comprendre les strategies de modulation disponibles. Un bref historique de ces strategies est fait avant de mettre l'emphase sur la modulation vectorielle qui sera celle utilisee pour l'application en cours. Les differents modules sont assembles dans une simulation Matlab pour confirmer leur bon fonctionnement et comparer les resultats de la simulation avec les calculs theoriques. Differents algorithmes permettant de traquer et maintenir un point de fonctionnement optimal sont presentes. Le comportement de la riviere est etudie afin d'evaluer l'ampleur des perturbations que le systeme devra gerer. Finalement, une nouvelle approche est presentee et comparee a une strategie plus conservatrice a l'aide d'un autre modele de simulation Matlab.

  5. Conception et optimisation d'une peau en composite pour une aile adaptative =

    NASA Astrophysics Data System (ADS)

    Michaud, Francois

    Les preoccupations economiques et environnementales constituent des enjeux majeurs pour le developpement de nouvelles technologies en aeronautique. C'est dans cette optique qu'est ne le projet MDO-505 intitule Morphing Architectures and Related Technologies for Wing Efficiency Improvement. L'objectif de ce projet vise a concevoir une aile adaptative active servant a ameliorer sa laminarite et ainsi reduire la consommation de carburant et les emissions de l'avion. Les travaux de recherche realises ont permis de concevoir et optimiser une peau en composite adaptative permettant d'assurer l'amelioration de la laminarite tout en conservant son integrite structurale. D'abord, une methode d'optimisation en trois etapes fut developpee avec pour objectif de minimiser la masse de la peau en composite en assurant qu'elle s'adapte par un controle actif de la surface deformable aux profils aerodynamiques desires. Le processus d'optimisation incluait egalement des contraintes de resistance, de stabilite et de rigidite de la peau en composite. Suite a l'optimisation, la peau optimisee fut simplifiee afin de faciliter la fabrication et de respecter les regles de conception de Bombardier Aeronautique. Ce processus d'optimisation a permis de concevoir une peau en composite dont les deviations ou erreurs des formes obtenues etaient grandement reduites afin de repondre au mieux aux profils aerodynamiques optimises. Les analyses aerodynamiques realisees a partir de ces formes ont predit de bonnes ameliorations de la laminarite. Par la suite, une serie de validations analytiques fut realisee afin de valider l'integrite structurale de la peau en composite suivant les methodes generalement utilisees par Bombardier Aeronautique. D'abord, une analyse comparative par elements finis a permis de valider une rigidite equivalente de l'aile adaptative a la section d'aile d'origine. Le modele par elements finis fut par la suite mis en boucle avec des feuilles de calcul afin de valider la

  6. Une hanche douloureuse révélatrice d'une histiocytose osseuse multifocale

    PubMed Central

    Lahrach, Kamal; Alaoui, Adil; el Kadi, Khalid Ibn; Marzouki, Amine; Boutayeb, Fawzi

    2014-01-01

    L'histiocytose langerhansienne est une maladie rare qui touche principalement l'enfant et l'adulte jeune. Elle peut prendre plusieurs aspects, L'atteinte osseuse peut être uni- ou multifocale. Nous rapportons une observation d'histiocytose langerhansienne osseuse multifocale, révélée chez un patient âgé de 23 ans et ayant touché le col fémoral droit. La scintigraphie osseuse a permis de retrouver plusieurs localisations: l'os temporal, humérale et scapulaire droite. En raison du risque fracturaire, le patient a bénéficié d'une ostéosynthèse par vis-plaque DHS avec curetage biopsie de la lésion. L'examen histologique a révélé une histiocytose langerhansienne. L'évolution fut favorable après chimiothérapie par voie générale. PMID:25018840

  7. Tumeur stromale du mésentère: une cause inhabituelle d'une masse abdominale

    PubMed Central

    Tarchouli, Mohamed; Bounaim, Ahmed; Boudhas, Adil; Ratbi, Moulay Brahim; Ndjota, Bobby Nguele; Ali, Abdelmounaim Ait; Sair, Khalid

    2015-01-01

    Les tumeurs stromales gastro-intestinales (GIST) sont les tumeurs mésenchymateuses les plus fréquentes du tractus digestif. Elles représentent une entité nosologique individualisée depuis la découverte de l'expression quasi-constante de la protéine c-Kit détectée par la coloration immunohistochimique de l'antigène CD117. Des tumeurs avec les mêmes caractéristiques morphologiques et immuno-phénotypiques peuvent rarement apparaître en dehors du tractus gastro-intestinal. Nous rapportons le cas d'une jeune patiente de 34 ans présentant une masse tumorale mésentérique se révélant être de nature stromale sans aucun contact avec la paroi intestinale. Il s'agit d'une localisation très rare des tumeurs stromales à laquelle il faut penser en préopératoire afin d'avoir une conduite thérapeutique adaptée et efficace. PMID:26327998

  8. Une spondylodiscite tuberculeuse chez une transplantée rénale compliquée d’une mycose systémique

    PubMed Central

    Haddiya, Intissar; El Housni, Siham; El Harraqui, Ryme; Rhou, Hakima; Benamar, Loubna; Eziatouni, Fatima; Ouzeddoun, Naima; Bayahia, Rabia

    2014-01-01

    En transplantation, les complications infectieuses sont fréquentes et de diagnostic souvent délicat. Elles peuvent coexister chez le transplanté rénal rendant leur diagnostic encore plus difficile. Le but de ce cas clinique est de discuter les difficultés diagnostiques et de surveillance de deux types de pathologies assez fréquentes chez le transplanté rénal, qui sont la tuberculose et la mycose, à travers l’observation clinique d’une patiente de 24 ans transplantée rénale qui présente une spondylodiscite tuberculeuse et qui développe secondairement une septicémie à Candida non albicans à point de départ urinaire dont le seul point d’appel est la fièvre post opératoire. PMID:25667684

  9. Hémothorax spontané révélant une vascularite de Wegener chez une femme enceinte

    PubMed Central

    Serhane, Hind; Yassine, Msougar; Amro, Lamyae

    2016-01-01

    L’hémothorax spontané demeure une pathologie rare. Ses étiologies sont multiples mais restent parfois inconnues. Chez certains patients, la thoracotomie peut être le seul recours pour déterminer son origine. Les vascularites n’ont pas été rapporté comme cause habituelle des hémothorax spontanés. La grossesse ne semble pas avoir d’effet causal, ni aggravant des hémothorax spontanés, ni des vascularites. Nous rapportons une observation assez particulière d’une jeune patiente, présentant au cours de sa grossesse un hémothorax spontané secondaire à une vasularite de type Wegener, diagnostiquée par la biopsie pleurale faite au cours d’une thoracotomie exploratrice et confirmée par le dosage des ANCA. PMID:28154726

  10. Le syndrome d’Usher: à propos d’une observation

    PubMed Central

    Daoudi, Chama; boutimzine, Noureddine; Haouzi, Samia El; Lezrek, Omar; Tachfouti, Samira; Lezrek, Mounir; Laghmari, Mina; Daoudi, Rajae

    2017-01-01

    Résumé Le syndrome d'Usher est une maladie génétique comportant une double atteinte sensorielle (auditive et visuelle) appelée surdicécité. Nous rapportons l'observation d'un patient de 50 ans, issue d'un mariage consanguin présentant une surdité congénitale avec une fonction vestibulaire normale et une rétinopathie pigmentaire responsable d'une baisse bilatérale de l'acuité visuelle apparue vers l'âge de 16 ans. Cette association compose le type 2 du syndrome d'Usher, affection rare de transmission autosomique récessive. La chirurgie de la cataracte a permis une amélioration de l'acuité visuelle chez ce patient. PMID:28979619

  11. Mode de révélation particulier d'une tumeur brune chez une patiente hémodialysée chronique

    PubMed Central

    El Harraqui, Ryme; Karimi, Ilham; Chemlal, Abdeljalil; Ismaili, Fatiha Alaoui; Haddiya, Intissar

    2014-01-01

    Les tumeurs brunes constituent une complication rare mais sévère de la dialyse, le plus souvent asymptomatique. Nous rapportons le cas d'une patiente dont le mode de révélation de la tumeur brune fut atypique. Observation médicale: Madame F. est une patiente hémodialysée chronique depuis 14 ans suite à une néphropathie indéterminée. Sur le plan phosphocalcique, elle présente une ostéoporose depuis plus de 10 ans, ainsi qu'une hyperparathyroïdie secondaire. A la date du 24 octobre 2013, elle rapporte qu'elle a constaté la présence d'une petite « bosse » pariétale, apparue de façon spontanée la veille, sans notion de traumatisme. A l'examen clinique, nous trouvons une petite tuméfaction de 2cm de diamètre environs, de consistance dure, indolore, mobile par rapport au cuir chevelu. L’échographie a conclu à un lipome. Le lendemain matin, la patiente entre dans un état de coma profond. Le scanner cérébral a révélé la présence d'un hématome extradural associé à un hématome superficiel extra-crânien en regard d'une lyse de l'os pariétal, qui est en fait une tumeur brune. La patiente est transférée en réanimation où elle décède dans la journée. PMID:25422698

  12. Validation materielle d'une architecture generique de reseaux avioniques basee sur une gestion modulaire de la redondance

    NASA Astrophysics Data System (ADS)

    Tremblay, Jose-Philippe

    Les systemes avioniques ne cessent d'evoluer depuis l'apparition des technologies numeriques au tournant des annees 60. Apres le passage par plusieurs paradigmes de developpement, ces systemes suivent maintenant l'approche " Integrated Modular Avionics " (IMA) depuis le debut des annees 2000. Contrairement aux methodes anterieures, cette approche est basee sur une conception modulaire, un partage de ressources generiques entre plusieurs systemes et l'utilisation plus poussee de bus multiplexes. La plupart des concepts utilises par l'architecture IMA, bien que deja connus dans le domaine de l'informatique distribuee, constituent un changement marque par rapport aux modeles anterieurs dans le monde avionique. Ceux-ci viennent s'ajouter aux contraintes importantes de l'avionique classique telles que le determinisme, le temps reel, la certification et les cibles elevees de fiabilite. L'adoption de l'approche IMA a declenche une revision de plusieurs aspects de la conception, de la certification et de l'implementation d'un systeme IMA afin d'en tirer profit. Cette revision, ralentie par les contraintes avioniques, est toujours en cours, et offre encore l'opportunite de developpement de nouveaux outils, methodes et modeles a tous les niveaux du processus d'implementation d?un systeme IMA. Dans un contexte de proposition et de validation d'une nouvelle architecture IMA pour un reseau generique de capteurs a bord d?un avion, nous avons identifie quelques aspects des differentes approches traditionnelles pour la realisation de ce type d?architecture pouvant etre ameliores. Afin de remedier a certaines des differentes lacunes identifiees, nous avons propose une approche de validation basee sur une plateforme materielle reconfigurable ainsi qu'une nouvelle approche de gestion de la redondance pour l'atteinte des cibles de fiabilite. Contrairement aux outils statiques plus limites satisfaisant les besoins pour la conception d'une architecture federee, notre approche de

  13. Aménorrhée chimio induite chez une population marocaine: à propos d'une cohorte retrospective

    PubMed Central

    Brahmi, Sami Aziz; Ziani, Fatima Zahra; Youssef, Seddik; Afqir, Said

    2016-01-01

    Introduction Le cancer du sein est un des cancers les plus fréquents chez la femme en pré ménopause et son traitement peut compromettre la fertilité. En effet, la chimiothérapie utilisée dans le cancer du sein peut conduire à une aménorrhée transitoire ou permanente chez les femmes non ménopausées. Méthodes Nous avons mené une étude rétrospective au service d'oncologie médicale du CHU Mohammed VI d'Oujda sur une période de 3 ans allant de janvier 2009 à décembre 2011 incluant les patientes jeunes ayant un cancer du sein localisé, pour étudier l'incidence de l'aménorrhée chimio-induite (ACI), ainsi que les facteurs prédictifs intervenant dans sa survenue. Résultats Dans notre série 74% de nos patientes ont présenté une ACI et 33.6% de nos patientes ont présenté une aménorrhée chimio-induite définitive. Plusieurs facteurs ont été étudiés à la recherche d’élément prédictifs de la survenue de l'aménorrhée. Concernant le facteur âge, l'analyse a montré que les femmes avec un âge supérieur à 40 ans étaient plus susceptibles de présenter une aménorrhée que celles avec un âge inférieur à 40 avec un pourcentage de 95,7% versus 56,1% avec une différence significative (p = 0.003). Conclusion L'incidence dans notre étude de l'ACI semble comparable à celle retrouvé dans la littérature, l’âge dans notre étude est le facteur prédictif le plus prédominant dans sa survenue. PMID:27642399

  14. UNED OER Experience: From OCW to Open UNED

    ERIC Educational Resources Information Center

    Ros, Salvador; Hernández, Roberto; Read, Timothy; Artacho, Miguel Rodriguez; Pastor, Rafael; Orueta, Gabriel Diaz

    2014-01-01

    Much has happened with open software, there has been a global attitude shift in the education community toward the open sharing of educational courses and resources. As the largest public distance education university in Spain, Universidad Nacional de Educacio´n a Distancia (UNED) has had a clear commitment to open learning and content since its…

  15. Pathomimie de l'enfant: à propos d'une observation

    PubMed Central

    Abilkassem, Rachid; Dini, Nezha; Ourai, Hakim; Kmari, Mohamed; Agadr, Aomar

    2013-01-01

    La pathomimie cutanée se définit comme une maladie factice, provoquée dans un etat de conscience claire par le patient lui-même, au niveau du revêtement cutanéo-muqueux et/ou des phanères. Rare chez l'enfant, il s'agit d'une manifestation psychopathologique potentiellement grave et souvent difficile à prendre en charge. Nous rapportons le cas d'une fillette de 10 ans présentant une pathomimie sous forme de lésions excoriées multiples du visage. PMID:23504605

  16. Une fistule recto-vaginale rentrant dans le cadre d'un syndrome de Currarino

    PubMed Central

    Idrissi, Mounia Lakhdar; Babakhoya, Abdeladim; Bouabdellah, Youssef; Hida, Mostapha

    2011-01-01

    Le syndrome de Currarino (SC) est défini par une triade rassemblant une malformation ano-rectale, une agénésie sacrée et une tumeur pré-sacrée. Nous rapportons le cas d'une fille de 4 ans et demi ayant été admise en consultation de gastro-entérologie pédiatrique pour constipation avec issue de selle à travers un orifice vulvaire. La radiographie du rachis avait montré une agénésie sacrée. Le fistulo-scanner a mis en évidence une fistule recto-vaginale et l'IRM pelvienne a confirmé l'agénésie sacrée et a retrouvé une méningocèle antérieure. La découverte d'une malformation ano-rectale doit faire chercher une autre anomalie de la triade de Currarino. Cette affection, rare, nécessite une prise en charge médico-chirurgicale assez complexe. PMID:22384297

  17. Toxoplasmose oculaire atypique chez une femme congolaise de 72 ans: à propos d'une observation

    PubMed Central

    Bienvenu, Yogolelo Asani; Angel, Musau Nkola; Eric, Kasamba Ilunga; Socrate, Kapalu Mwangala; Sebastien, Mbuyi Musanzayi; Philippe, Cilundika Mulenga; Leon, Kabamba Ngombe; Bruno, Iye Ombamba Kayimba; Gaby, Chenge Borasisi

    2015-01-01

    Les auteurs rapportent un cas de toxoplasmose oculaire binoculaire, rarement décrit dans la littérature, chez une personne âgée de 72 ans, de sexe féminin, à laquelle s'associe une rétinite pigmentaire unilatérale. Cette observation permet d'attirer l'attention de la communauté scientifique sur les autres formes ou variétés de présentation moins courantes, « atypiques », pouvant être rencontrées ou associées à la toxoplasmose oculaire. PMID:26958130

  18. Les agressions sexuelles des jeunes ayant une incapacité ou une maladie chronique

    PubMed Central

    Kaufman, M

    2011-01-01

    Pour diverses raisons, les enfants et les adolescents ayant une incapacité ou une maladie chronique sont plus vulnérables aux agressions sexuelles. Les dispensateurs de soins, de même que les parents et les éducateurs, doivent se méfier davantage de la possibilité d’agression sexuelle au sein de cette population. Les médecins, tout particulièrement, doivent prôner des politiques pour prévenir ou déceler les agressions dans les hôpitaux, les écoles et autres établissements. Ces politiques incluent le dépistage détaillé et la surveillance étroite des employés et des bénévoles, la présence d’un chaperon aux examens physiques et aux interventions thérapeutiques, la supervision des sorties et une culture qui favorise la vie privée du patient en établissement. De plus, les médecins doivent favoriser la conscience de soi et l’habilitation des patients et leur donner très tôt des conseils préventifs au sujet de la sexualité, de l’habilitation personnelle et des risques d’agression. Le présent document de principes remplace celui que la Société canadienne de pédiatrie a publié en 1997.

  19. Tumeur d'Abrikossoff juxta axillaire: une localisation rare d'une tumeur très rare, à propos d'un cas

    PubMed Central

    Amourak, Sarah; Bouzoubaa, Wael; Jayi, Sofia; Alaoui, Fatimazahra Fdili; Chaara, Hikmat; Melhouf, Moulay Abdelilah

    2015-01-01

    Décrite pour la première fois en 1926 par Abrikossoff, les tumeurs à cellules granuleuses (TCG) sont bénignes et uniques dans la grande majorité des cas. Les principales localisations sont la cavité orale, puis les tissus sous-cutanés de la tête et du cou et les seins. La pathogenèse a été longtemps débattue, après avoir proposé initialement une origine musculaire striée les études récentes sont en faveur d'une origine neurogène schwannienne confirmées par une étude immunohistochimique. Le traitement de la tumeur à cellules granuleuses est un traitement chirurgical, il permet un diagnostic de certitude par l'examen anatomo-pathologique de la pièce d'exérèse qui doit rechercher les limites d'exérèse et la présence de critères de malignité. Leur évolution est souvent favorable si la résection chirurgicale est complète. Nous rapportons ici le cas d'une tumeur d'Abrikossoff à localisation juxta axillaire et nous profitons de faire une revue de la littérature afin de mettre le point sur cette entité rare. PMID:26328001

  20. Néphrocalcinose compliquant une miliaire tuberculeuse chez un nourrisson

    PubMed Central

    El Maghraoui, Jaouad; Souilmi, Fatima Zahrae; Hbibi, Mohamed; Houssaini, Tarik Sqalli; Hida, Mustapha

    2015-01-01

    La néphrocalcinose se définit par la présence anormale dans le parenchyme rénal de dépôts calciques pouvant résulter de différentes affections. Nous rapportons le cas d'un nourrisson de 7 mois chez qui nous avons diagnostiqué une hypercalcémie compliquée par une néphrocalcinose secondaire à une tuberculose miliaire aggravée par l'intoxication à la vitamine D améliorée sous hyperhydratation, furosémide et glucocorticoïdes. A travers ce travail, nous insistons sur l'intérêt de la recherche d'une hypercalcémie devant toute infection tuberculeuse, de la prise en charge rapide et adaptée sans oublié d'interrompre la supplémentation en vitamine D. PMID:26309458

  1. L’alimentation des enfants ayant une déficience neurologique

    PubMed Central

    2009-01-01

    La malnutrition, qu’il s’agisse de sous-alimentation ou de suralimentation, est courante chez les enfants ayant une déficience neurologique. Les besoins en énergie sont difficiles à définir au sein de cette population hétérogène. De plus, on manque d’information sur ce qui constitue la croissance normale chez ces enfants. Des facteurs non nutritionnels peuvent influer sur la croissance, mais des facteurs nutritionnels, tels qu’un apport calorique insuffisant, des pertes excessives d’éléments nutritifs et un métabolisme énergétique anormal, contribuent également au retard de croissance de ces enfants. La malnutrition est liée à une importante morbidité, tandis que la réadaptation nutritionnelle améliore l’état de santé global. Le soutien nutritionnel doit faire partie intégrante de la prise en charge des enfants ayant une déficience nutritionnelle et viser non seulement à améliorer l’état nutritionnel, mais également la qualité de vie des patients et de leur famille. Au moment d’envisager une intervention nutritionnelle, il faut tenir compte du dysfonctionnement oromoteur, du reflux gastro-œsophagien et de l’aspiration pulmonaire, et une équipe multidisciplinaire doit se concerter. Il faut repérer rapidement les enfants vulnérables à des troubles nutritionnels et procéder à une évaluation de leur état nutritionnel au moins une fois par année, et plus souvent chez les nourrissons et les jeunes enfants ou chez les enfants qui risquent de souffrir de malnutrition. Il faut optimiser l’apport oral s’il est sécuritaire, mais entreprendre une alimentation entérale chez les enfants ayant un dysfonctionnement oromoteur qui provoque une aspiration marquée ou chez ceux qui sont incapables de maintenir un état nutritionnel suffisant au moyen de l’apport oral. Il faut réserver l’alimentation par sonde nasogastrique aux interventions à court terme, mais si une intervention nutritionnelle prolongée s

  2. Pseudotumeur cardiaque révélant une maladie de Behçet

    PubMed Central

    Nya, Fouad; Abdou, Abdessamad; Bamous, Mehdi; Moutakiallah, Younes; Atmani, Noureddine; Seghrouchni, Aniss; Houssa, Mahdi Ait; Boulahya, Abdellatif

    2017-01-01

    La thrombose intracardiaque est une complication rare de la maladie de Behçet (MB), qui peut se présenter comme une tumeur intracardiaque. Sa découverte précède, dans la moitié des cas, le diagnostic de MB. La mortalité élevée peut être en rapport avec des complications post-chirurgicales et/ou une atteinte associée des artères pulmonaires. Nous rapportons l’observation d’un jeune patient de 29 ans, aux antécédents d’aphtose bipolaire, qui a bénéficie d’une intervention chirurgicale après la découverte d’une tumeur de l’atrium et du ventricule droits. Il s’agissait d’un thrombus à l’examen anatomopathologique et dans les suites opératoires nous avons diagnostiqué une MB. L’évolution a été favorable sous traitement médical associant une corticothérapie, de la colchicine et des antivitamines K (AVK). La découverte d’une masse intracardiaque chez un sujet jeune doit faire évoquer le diagnostic de thrombus cardiaque et de maladie de Behçet, même en l’absence de facteur ethnique ou géographique prédisposant. PMID:28533874

  3. Syndrome coronarien aigue suite à une injection accidentelle intraveineuse de Bupivacaine

    PubMed Central

    Koita, Siriman Abdoulaye; Bouhabba, Najib; Salaheddine, Fjouji; Bensghir, Mustapha; Charki, Haimeur

    2015-01-01

    Les erreurs médicamenteuses constituent une complication très redoutable en anesthésie. La fréquence des erreurs médicamenteuses par administration serait de l'ordre 1/10 000 à 1/1000. Nous rapportons un cas d'injection accidentelle de bupivacaine en intraveineuse directe. Il s'agissait d'un jeune patient classé ASA I qui était prévu pour cure chirurgicale d'une hydrocèle unilatérale sous rachianesthésie. Une injection de 12,5 mg de bupivacaine et 25 µg de fentanyl étaient injectés après un reflux net du liquide céphalorachidien sans incident. Après installation de la rachianesthésie, le début de l'intervention était autorisé sans incidents. Une sédation de confort était décidée. Juste après apparaissait des troubles de rythme à type tachycardie ventriculaire avec une élévation de taux de troponines en post opératoire. L’évolution était marquée par une normalisation de la troponine au troisième jour post opératoire et sorti de l'hôpital au cinquième jour. PMID:26889325

  4. Le kyste hydatique du cordon spermatique: une localisation exceptionnelle

    PubMed Central

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

    2011-01-01

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

  5. Cause rare d'une perforation de la cloison nasale

    PubMed Central

    Jahidi, Ali; Hemmaoui, Bouchaïb; Itoua, Wulfran Rosaire; Errami, Noureddine; Benariba, Fouad

    2014-01-01

    Les perforations de la cloison nasale constituent une pathologie fréquente en ORL. Leurs causes sont multiples et restent dominées par les traumatismes chirurgicaux. Les étiologies infectieuses et notamment la tuberculose sont rares. Nous présentons le cas d'une patiente ayant bénéficié d'une méatotomie bilatérale et chez laquelle une perforation de la cloison nasale a été découverte lors d'un examen systématique à un an de son intervention. D'abord considérée comme une complication de la chirurgie, la biopsie des berges de la perforation a permis de déterminer son origine tuberculeuse. La présentation clinique des perforations de la cloison nasale n'est pas spécifique. Elles sont souvent asymptomatiques et de découverte fortuite. Les traumatismes notamment chirurgicaux sont le plus siuvent en cause. L′orogine tuberculeuse resta très rare. Le diagnostic de certitude de tuberculose repose sur la biopsie des berges de cette perforation. Le but de ce travail est de mettre en avant l'intérêt de la biopsie dans le diagnostic de la tuberculose de la cloison nasale. Cette biopsie doit être systématique même en cas d'antécédents de chirurgie endonasale qui est le plus souvent en cause dans les perforations de la cloison nasale. PMID:24932334

  6. Études des propriétés électro-optiques d'une série de diphtalocyanines de terres rares

    NASA Astrophysics Data System (ADS)

    Videlot, C.; Fichou, D.; Garnier, F.

    1998-06-01

    In this work, we describe the study of photovoltaic cells for a series of rare earth diphthalocyanines. This p type organic compounds have been used in Schottky and pn configurations. Current-voltage curves and action spectra show different replies in energy's conversion according to the rare earth of the diphthalocyanine. Dans ce travail, nous décrivons l'étude de cellules photovoltaïques pour une série de diphtalocyanines de terres rares. Ces composés organiques de type p ont été étudiés dans des configurations Schottky et hétérojonction pn. Les courbes de courant-tension et les spectres d'action montrent des réponses différentes dans la conversion de l'énergie suivant la terre rare de la diphtalocyanine.

  7. Electrodiagnosis of ulnar neuropathy at the elbow (Une): a Bayesian approach.

    PubMed

    Logigian, Eric L; Villanueva, Raissa; Twydell, Paul T; Myers, Bennett; Downs, Marlene; Preston, David C; Kothari, Milind J; Herrmann, David N

    2014-03-01

    In ulnar neuropathy at the elbow (UNE), we determined how electrodiagnostic cutoffs [across-elbow ulnar motor conduction velocity slowing (AECV-slowing), drop in across-elbow vs. forearm CV (AECV-drop)] depend on pretest probability (PreTP). Fifty clinically defined UNE patients and 50 controls underwent ulnar conduction testing recording abductor digiti minimi (ADM) and first dorsal interosseous (FDI), stimulating wrist, below-elbow, and 6-, 8-, and 10-cm more proximally. For various PreTPs of UNE, the cutoffs required to confirm UNE (defined as posttest probability = 95%) were determined with receiver operator characteristic (ROC) curves and Bayes Theorem. On ROC and Bayesian analyses, the ADM 10-cm montage was optimal. For PreTP = 0.25, the confirmatory cutoffs were >23 m/s (AECV-drop), and <38 m/s (AECV-slowing); for PreTP = 0.75, they were much less conservative: >14 m/s, and <47 m/s, respectively. (1) In UNE, electrodiagnostic cutoffs are critically dependent on PreTP; rigid cutoffs are problematic. (2) AE distances should be standardized and at least 10 cm. Copyright © 2013 Wiley Periodicals, Inc.

  8. Analyse experimentale des performances d'une batterie au lithium pour l'aeronautique

    NASA Astrophysics Data System (ADS)

    Bonnin, Romain

    Ce memoire a pour objectif d'identifier et d'etudier les performances necessaires pour qu'une batterie au lithium puisse etre utilisee dans le secteur de l'aeronautique. C'est pourquoi dans le cadre de notre recherche, nous allons proposer une procedure de tests permettant d'analyser et de determiner si la batterie au lithium peut etre implantee dans un avion. En vue de repondre a l'analyse des performances, une etude des fonctionnalites demandees par l'avion ainsi que des normes preexistantes vont etre effectuees. Suite a cette etape, nous allons elaborer un banc d'essais. Une fois le banc d'essais acheve, nous allons tester une batterie au lithium qui est supposee disposer de toutes les caracteristiques techniques requises pour etre implantee dans un avion. Ces tests nous permettront donc d'emettre un avis sur l'utilisation des batteries au lithium dans le domaine de l'aeronautique.

  9. Fistule vesico-sigmoïdienne compliquant une hydatidose intestinale: à propos d'un cas rare

    PubMed Central

    Lahyani, Mounir; Jabbour, Younes; Karmouni, Tarik; Elkhader, Khalid; Koutani, Abdellatif; Andaloussi, Ahmed Ibn attya

    2014-01-01

    La fistule colo-vésicale sur une hydatidose sigmoidienne est une entité pathologique exceptionnelle. Nous rapportions une nouvelle observation, ou seront rappelées les principales données diagnostique et thérapeutique de cette affection. PMID:25722790

  10. Maladie de Horton révélée par une dyspnée

    PubMed Central

    Mahfoudhi, Madiha; Mamlouk, Habiba; Turki, Sami; Kheder, Adel

    2015-01-01

    Les manifestations pleuro-pulmonaires de la maladie de Horton sont rares et peu connues. Elles peuvent être inaugurales, à l'origine d'un retard à la prise en charge si elles sont méconnues. Il s'agissait d'un patient âgé de 75 ans, admis pour une dyspnée, une toux chronique et une fièvre. Il a reçu une antibiothérapie et a bénéficié d'une fibroscopie bronchique avec lavage broncho-alvéolaire à la recherche d'un germe, qui a révélé plutôt, une alvéolite lymphocytaire. L’évolution était marquée par la persistance des signes cliniques et du syndrome inflammatoire biologique. Un angio-scanner thoracique et une échographie cardiaque étaient sans anomalies. Une origine cardiaque, musculaire, hématologique, néoplasique, vasculaire ou métabolique de la dyspnée a été éliminée. Une maladie de Horton a été évoquée. La biopsie de l'artère temporale a confirmé le diagnostic d'une maladie de Horton. L’évolution sous corticothérapie était marquée par la disparition des signes cliniques et biologiques. Les manifestations pleuro-pulmonaires au cours de la maladie de Horton sont rares, et classiquement, rarement révélatrices de la maladie. La dyspnée peut initialement égarer le diagnostic vers d'autres étiologies notamment infectieuses. Le but de ce travail est d'insister sur le fait que la connaissance de ces différentes manifestations respiratoires au cours de la maladie de Horton (toux persistante, dyspnée, épanchement pleural) est utile au clinicien afin de prescrire une corticothérapie, chez un sujet le plus souvent âgé ayant un état fébrile et inflammatoire prolongé, permettant ainsi d’éviter l'apparition de complications. PMID:26161171

  11. Etiologie Rare de Sinusites Nosocomiales en Milieu de Reanimation - A Propos d'une Observation

    PubMed Central

    Messadi, A.A.; Oueslati, S.; Thabet, L.; Bousselmi, K.; Menif, E.

    2006-01-01

    Summary Les sinusites nosocomiales ne sont pas rares en réanimation. Elles surviennent en général dans les suites d'une intubation nasotrachéale voire même orotrachéale. Le tubage gastrique peut être à lui seul à l'origine d'une sinusite nosocomiale. Nous rapportons le cas d'une patiente hospitalisée qui a été victime de brûlures étendues chez qui la sonde nasogastrique a été à l'origine d'une pansinusite dont l'issue a été fatale. PMID:21991055

  12. Quand la biopsie cutanée peut étiqueter une épilepsie

    PubMed Central

    Harmouch, Taoufiq; Gallouj, Salim; Znati, Kaoutar; Sennou, Aicha Slassi; Belahcen, Faouzi; Amarti, Afaf

    2011-01-01

    La maladie de Lafora (ML) représente une forme rare et grave d’épilepsie myoclonique progressive. C'est une affection à transmission autosomique récessive, hétérogène sur le plan génétique. Nous rapportons le cas d'une adolescente de 16 ans, issue de parents consanguins de premier degré, qui présente depuis l’âge de 14 ans des crises d’épilepsie et des myoclonies. L'examen neurologique a montré un syndrome cérébelleux et une détérioration intellectuelle. La biopsie cutanée était indispensable pour orienter le diagnostic. La ML a un pronostic constamment fatal. L’étude histologique confirme le diagnostic et l’étude moléculaire peut aider à établir un conseil génétique. PMID:22187608

  13. Sidération myocardique au cours d'une intoxication au monoxyde de carbone (CO) chez une femme enceinte

    PubMed Central

    Coulibaly, Mahamadoun; Berdai, Mohamed Adnane; Labib, Smael; Harandou, Mustapha

    2015-01-01

    L'intoxication au monoxyde de carbone (CO) est la première cause de décès par intoxication en France. La littérature est ancienne et peu connue. Les signes les plus fréquents de l'intoxication sont la triade: Céphalées; asthénie, faiblesse musculaire surtout des membres inférieurs. Ses conséquences sont potentiellement graves pour le fœtus quand elle survient chez la femme enceinte, il est particulièrement exposé au risque d'hypoxie en raison de la forte affinité de son hémoglobine pour le CO qui traverse aisément le placenta. Les événements cardiovasculaires ne sont pas rares et peuvent être responsable d'une morbi-mortalité assez importante qui peuvent être d'apparition rapide ou secondaire mais régressent habituellement en quelques jours. Des SCA peuvent survenir lors d'une une intoxication au CO avec à l'extrême infarctus myocardique avec surélévation du segment ST. Il paraît légitime de proposer pour toutes les patientes: l’éloignement maternel de la source de CO; l'oxygénothérapie à 100% au masque facial par les services de secours et pendant le transfert; le traitement par oxygénothérapie hyperbare pour toutes les femmes enceintes, le plus rapidement possible et quelque soit l’âge gestationnel. PMID:26405502

  14. Dynamique d'une frontière libre : un siège fascinant de morphogénèse

    NASA Astrophysics Data System (ADS)

    Misbah, Chaouqi; Müller-Kurmbhaar, Heiner

    Un front de solidification, dont le mouvement est limité par une simple diffusion, est le siège d'une myriade de morphogénèses statiques et dynamiques, allant d'une dendrite aux fractals, et d'un front cellulaire stationnaire au chaos spatio-temporel. Plusieurs de ces caractéristiques sont communes à une vaste liste de systèmes hors équilibre. Même l'organisation spatio-temporelle d'une population d'entités vivantes, telles que les bactéries, présente une forte similarité avec celle d'un front de croissance.

  15. Reconstruction d’une Carbonisation du Pouce par Lambeau Chinois

    PubMed Central

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

    2010-01-01

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

  16. La neurobrucellose: une cause curable de surdité neurosensorielle à ne pas méconnaitre

    PubMed Central

    Malhi, Alae Bezzari; Ridal, Mohamed; Bouchal, Siham; Belahsen, Mohammed Faouzi; El Alami, Mohamed-Nourdine

    2015-01-01

    La brucellose est une zoonose ubiquitaire touchant en particulier les pays méditerranéens et le Moyen-Orient. Les manifestations neurologiques sont assez diverses. Nous rapportons l'observation d'un patient âgé de 45 ans, agriculteur, ayant consulté pour une surdité profonde bilatérale depuis 2 mois associée à des céphalées, des épisodes d'hémiparésie à bascule, de trouble de langage, spontanément résolutifs en quelques minutes et des sensations vertigineuses intermittentes depuis 09 mois. Les résultats de la ponction lombaire, de l'imagerie par résonnance magnétique et surtout la sérologie ont permis de conclure à une neurobrucellose. L’évolution sous bi-antibiothérapie a été favorable, avec régression des signes neurologiques, normalisation du LCR et amélioration de la surdité. La neurobrucellose est une affection grave dont le pronostic dépend de la précocité du diagnostic et du traitement. Nous pensons qu'un tableau clinique associant une surdité neurosensorielle et une symptomatologie neurologique progressive doit évoquer en premier une neurobrucellose, d'autant plus que le patient est à risque et dans les pays où cette maladie est endémique. PMID:26889303

  17. Une recension des écrits concernant la réalité psychoaffective des femmes ayant une vulvodynie : Difficultés rencontrées et stratégies développées

    PubMed Central

    Cantin-Drouin, Maude; Damant, Dominique; Turcotte, Daniel

    2008-01-01

    HISTORIQUE : Au cours des trois dernières décennies, une attention grandissante a été portée à l’étude du syndrome de vulvodynie, soit un inconfort vulvaire chronique inexpliqué, éprouvé en l’absence de pathologie précisée. En plus d’avoir des répercussions physiques, l’expérience de la vulvodynie comporte une dimension psychosociale. OBJECTIF : Cet article vise à faire une recension des écrits sur la réalité psychoaffective des femmes qui éprouvent une vulvodynie. MÉTHODE : Une recherche documentaire basée sur une exploration systématique de textes présentant des résultats de recherche et recensés dans les principales banques de données en sciences sociales, dont Dissertation Abstracts, Current Contents et PsycINFO, a été réalisée. RÉSULTATS : Cette recension des écrits révèle, malgré la présence de certains résultats divergents, que les femmes ayant une vulvodynie affrontent souvent des difficultés identitaires et psychologiques, qui sont influencées notamment par les normes sociales de sexualité et de féminité. Pour composer avec ces difficultés, les femmes développent différentes stratégies visant à diminuer le stress occasionné par la douleur et à améliorer leur bien-être psychologique. CONCLUSION : Les difficultés relationnelles et psychologiques vécues par les femmes ayant une vulvodynie ne découlent pas seulement de la douleur physique, mais aussi du sens qu’elles lui accordent, souvent influencé par les discours sociaux sur l’hétérosexualité et la féminité. Il importe donc d’intervenir auprès des femmes en tenant compte de l’influence du contexte social tout en poursuivant le développement des connaissances sur les aspects psychosociaux de cette expérience. PMID:18592063

  18. Le pronostic statural après une pseudo-puberté précoce par déficit en 11ß hydroxylase chez une fille de 7 ans: à propos d'un cas avec revue de la literature

    PubMed Central

    Latrech, Hanane; Gaouzi, Ahmed

    2015-01-01

    L'hyperplasie congénitale des surrénales par déficit en 11ß hydroxylase se voit dans 5 à 10% des cas et est diagnostiquée, habituellement, devant des signes de virilisation d'un nouveau né ou d'un fœtus 46 XX et plus tard devant une HTA avec une hypokaliémie. Le pronostic de taille chez ces patients est très souvent compromis. Nous rapportons le cas d'un déficit en 11ß hydroxylase chez une enfant âgée de 7 ans révélé par une pseudo- puberté précoce traitée par hydrocortisone. La survenue d'une puberté précoce centrale complique encore plus la situation par la mise en jeu du pronostic de taille finale et nécessitant une prise en charge thérapeutique particulière. PMID:26113905

  19. Une complication exceptionnelle du tétanos généralisé: l’embolie pulmonaire

    PubMed Central

    Regaieg, Kais; Bahloul, Mabrouk; Gargouri, Rahma; Bouattour, Abir; Chelly, Hèdi; Bouaziz, Mounir

    2016-01-01

    Le tétanos est une maladie caractérisée par une paralysie spastique et des spasmes. C’est une pathologie grave. Elle nécessite une prise en charge en milieu de réanimation. La mortalité est essentiellement liée aux complications neurovégétatives et infectieuses. Les complications thromboemboliques sont exceptionnelles au cours de cette maladie. A notre connaissance, l’embolie pulmonaire n’a jamais été rapportée et confirmée au cours du tétanos généralisé. Nous présentons à travers cette observation un cas de tétanos généralisé compliqué d’une embolie pulmonaire fibrino cruorique. PMID:28292134

  20. Soins primaires aux adultes ayant une déficience développementale

    PubMed Central

    Sullivan, William F.; Berg, Joseph M.; Bradley, Elspeth; Cheetham, Tom; Denton, Richard; Heng, John; Hennen, Brian; Joyce, David; Kelly, Maureen; Korossy, Marika; Lunsky, Yona; McMillan, Shirley

    2011-01-01

    Résumé Objectif Mettre à jour les lignes directrices canadiennes de 2006 sur les soins primaires aux adultes ayant une déficience développementale (DD) et présenter des recommandations pratiques fondées sur les connaissances actuelles pour traiter des problèmes de santé particuliers chez des adultes ayant une DD. Qualité des preuves Des professionnels de la santé expérimentés participant à un colloque et un groupe de travail subséquent ont discuté et convenu des révisions aux lignes directrices de 2006 en se fondant sur une recherche documentaire exhaustive, la rétroaction obtenue des utilisateurs du guide de pratique et les expériences cliniques personnelles. La plupart des preuves disponibles dans ce domaine viennent de l’opinion d’experts ou de déclarations consensuelles publiées (niveau III). Message principal Les adultes ayant une DD ont des problèmes de santé complexes, dont plusieurs diffèrent de ceux de la population en général. De bons soins primaires permettent d’identifier les problèmes de santé particuliers dont souffrent les adultes ayant une DD pour améliorer leur qualité de vie et leur accès aux soins de santé et prévenir la morbidité et le décès prématuré. Ces lignes directrices résument les problèmes de santé générale, physique, comportementale et mentale des adultes ayant une DD que devraient connaître les professionnels des soins primaires et présentent des recommandations pour le dépistage et la prise en charge en se basant sur les connaissances actuelles que les cliniciens peuvent mettre en pratique. En raison de l’interaction des facteurs biologiques, psychoaffectifs et sociaux qui contribuent à la santé et au bien-être des adultes ayant une DD, ces lignes directrices insistent sur la participation des aidants, l’adaptation des interventions, au besoin, et la consultation auprès de divers professionnels de la santé quand ils sont accessibles. Elles mettent aussi en évidence la

  1. Schwannome benin primitif retrovesical: une tumeur très rare à propos d'un cas

    PubMed Central

    Beddouche, Ali; Fahsi, Othemane; Kallat, Adil; El Bote, Hicham; Ziani, Idriss; El Sayegh, Hachem; Iken, Ali; Benslimane, Lounis; Nouini, Yassine

    2016-01-01

    Le schwannome est une tumeur le plus souvent bénigne, d'origine nerveuse se développant à partir des cellules de la gaine de Schwann. C'est une tumeur très rare tant par sa fréquence que par sa localisation rétrovésicale. L'examen anatomopathologique et immunohistochimique confirme le type histologique ainsi que le caractère bénin ou malin du schwannome. En raison des récidives, et du risque de transformation maligne, l'exérèse doit être complète. Nous rapportons le cas d'un patient âgé de 39 ans, admis pour une douleur pelvienne chronique à type de pesanteur, des signes irritatifs du bas appareil urinaire, et des troubles de transit. L'imagerie (échographie, TDM, IRM) a révélé la présence d'une masse pelvienne rétrovésicale, à paroi fine, latéralisée à gauche, mesurant 68x70x70 mm, exerçant un effet de masse sur la vessie et le sigmoïde. L'intervention chirurgicale menée par une laparotomie médiane a permis l'exérèse d'une masse retrovésicale bien encapsulée. L'examen anatomopathologique et immunohistochimique ont conclu à un schwannome bénin. La récidive et la transformation maligne bien que rare après chirurgie impose une surveillance post opératoire clinique et tomodensitométrique annuelle. PMID:27217902

  2. Cardiomyopathie du péripartum: à propos d’une observation et revue de la littérature

    PubMed Central

    Bouzerda, Abdelmajid

    2016-01-01

    La cardiomyopathie du péripartum ou cardiomyopathie gravidique primitive, est une entité rare et méconnue définie comme une insuffisance cardiaque systolique survenant le dernier mois de la grossesse ou les cinq premiers mois du postpartum en l'absence d'étiologie connue ou de cardiopathie préexistante. Nous rapportons l'observation d'une jeune patiente de 31 ans sans antécédents pathologiques particuliers admise pour une poussée d'insuffisance cardiaque gauche 1mois après son accouchement. Le contexte de péripartum nous a fait penser au diagnostic et a motivé la réalisation d'une Echocardiographie qui a confirmé cette entité. PMID:28154713

  3. Déshumidification de l'air d'une serre par contact direct à courants croisés avec une solution hygroscopique organique

    NASA Astrophysics Data System (ADS)

    Chraibi, A.; Jaffrin, A.; Makhlouf, S.; Bentounes, N.

    1995-07-01

    Greenhouse air can be dehumidified by direct contact with a desicant fluid on a trickle exchanger. The water vapour extraction rate depends on the hygroscopicity of the fluid and on the exchanger efficiency. An organic fluid, the triethylene glycol (TEG) at 90% concentration, has been tested. Cross corrugated cellulosic pads, of the type used in cooling, irrigated with TEG, were placed in a wind channel to dehumidify air at various speeds and temperatures. A semi-analytical model, based on energy and mass conservation, correctly reproduces the water vapor extraction rate and the enthalpy change of both fluids. It is shown that TEG trickling through a ventilated pad of 1 m^2 area and 0.1 m thickness can be used to extract 3 to 5 kg of water vapor per hour in greenhouse climate control applications. Several pads arranged in series can be used to decrease more efficiently the absolute humidity of the air, for other applications like food drying or industrial compressed air. Une technique de déshumidification de l'air des serres consiste à le soumettre au contact d'une solution hygroscopique au sein d'un échangeur ruisselant. Le taux d'extraction de vapeur d'eau dépend à la fois du pouvoir hygroscopique de la solution et de l'efficacité de l'échangeur. Une solution hygroscopique organique, le triéthylène glycol à 90% de concentration, a été expérimentée. Un échangeur ruisselant constitué de parois de cellulose ondulées à corrugations croisées, du type “cooling pad” pour serres agricoles, a été testé pour déshumidifier de l'air dans une soufflerie expérimentale. Un modèle semi-analytique, basé sur les équations de conservation de l'énergie et de masse, permet de rendre compte des échanges et de déduire les paramètres de sortie des deux fluides en contact, à partir des caractéristiques d'entrée. Cette étude permet de chiffrer à environ 3 à 5kg/h la capacité de déshumidification d'un panneau d'un mètre carré et de 10cm d

  4. Une nouvelle voie pour la conception des implants intervertébraux

    NASA Astrophysics Data System (ADS)

    Gradel, T.; Tabourot, L.; Arrieux, R.; Balland, P.

    2002-12-01

    L'objectif de notre travail est la conception d'une nouvelle génération d'implants intersomatiques qui s'adapte parfaitement à la géométrie des plateaux vertébraux en se déformant. Pour cela, nous avons utilisé une nouvelle démarche qui consiste à simuler entièrement le procédé de fabrication en l'occurrence l'emboutissage, Cette simulation, en concervant l'historique des sollicitations exercées sur le matériau lors de sa mise en œuvre permet de valider très précisément sa résistance mécanique en fin de cycle. Au cours de cette étude, nous avons mené en parallèle deux analyses dites “ coopératives ” : l'une fondée sur un modèle phénoménologique de type HILL et l'autre sur un modèle multi-échelles prenant en compte des phénomènes plus physiques afin d'acquérir une bonne connaissance du comportement du matériau lors de la déformation. C'est pour sa bonne résistance, sa biocompatibilité et ses propriétés radiologiques que nous avons choisi le T40 (titane pur) comme matériau.

  5. Pneumomédiastin compliquant une crise d’éclampsie: à propos d'un cas

    PubMed Central

    Doumiri, Mouhssine; Motiaa, Youssef; Oudghiri, Nezha; Saoud, Anas Tazi

    2014-01-01

    Le pneumomédiastin associé à l'emphysème sous cutané et le pneumothorax, sont des complications rares de la grossesse et surviennent au cours du travail obstétrical. Nous rapportons l'observation d'une parturiente de 25ans, sans antécédent pathologique particulier, admise pour une crise d’éclampsie à 36 semaines d'aménorrhées avec une mort fœtale et trouble de la conscience. L'examen clinique a montré un emphysème sous cutané étendu du visage jusqu’à l'abdomen sans notion de traumatisme et un score de Glasgow à 10. Après mise en condition, traitement de la crise d’éclampsie, stabilisation de la tension artérielle et retour à l’état de conscience, une TDM cervico-thoraco-abdominale a été demandée et a révélé la présence d'un pneumomédiastin important avec un discret pneumothorax droit postérieur et un pneumopéritoine important qui n'ont pas nécessité de drainage pleural. Deux jours après son admission, la patiente a expulsé un mort-né d'un poids de 1800 grammes avec forceps et sans efforts d'expulsions sous analgésie péridurale. Le contrôle radiologique à une semaine a noté une nette diminution de l'emphysème sous cutané et du pneumomédiastin. La patiente a quitté l'hôpital après dix jours. PMID:25838864

  6. Fissuration d'un composite a matrice ceramique dans une application de piece statique de turbine a gaz

    NASA Astrophysics Data System (ADS)

    Lebel, Larry

    Une procedure experimentale a ete developpee pour caracteriser les mecanismes de deterioration et la durabilite de materiaux composites a matrice ceramique (CMC) dans une application de piece statique de turbine a gaz. Tandis que la plupart des essais de caracterisation publies sur les materiaux CMC ont ete realises sous des conditions de chargement controle, la presente recherche tente de reproduire la relaxation des contraintes qui se produit normalement dans une piece statique a haute temperature. Dans l'experience proposee, un echantillon planaire de forme haltere est chauffe de facon cyclique sur une de ses faces et refroidi sur l'autre, tout en etant contraint dans ses deplacements. La contrainte de flexion resultante au centre de l'echantillon, mesuree par une cellule de charge, correspond a la contrainte de flexion qui a ete prealablement predite au centre des panneaux d'une chambre a combustion generique. Un materiau CMC multicouche compose d'une matrice d'alumine poreuse et de fibres NextelMD 720 a ete utilise pour developper l'experience. Des essais de calibration ont d'abord ete realises en utilisant un systeme de chauffage par lampe infrarouge, atteignant jusqu'a 1160 °C a la surface de l'echantillon. Un systeme laser au CO2 a par la suite ete utilise pour realiser des essais de deterioration a haute puissance, atteignant en fin d'essai des temperatures de surface excedant la limite de 1200 °C du materiau et des differences de temperature a travers l'epaisseur de plus de 1000 °C. Sous la puissance de chauffage imposee a amplitude constante, l'accumulation de dommage a fait en sorte d'augmenter la temperature en surface et les gradients de temperature a travers le materiau. Une reduction de la contrainte dans le temps a ete observee a cause du fluage, de la fissuration et de la delamination du materiau sous la condition de confinement du deplacement, menant a une stabilisation du niveau de dommage a une certaine profondeur dependant de la contrainte

  7. Lupus érythémateux systémique induit par l'isoniazide: une complication rare à craindre

    PubMed Central

    Jguirim, Mahbouba; Jbeli, Amna; Brahim, Hajer Ben; Mhenni, Amira; Youssef, Monia; Touzi, Mongi; Zrour, Sawssen; Bejia, Ismail; Bergaoui, Naceur

    2015-01-01

    Le lupus induit est défini comme un syndrome lupique généralement cutanéo-articulaire secondaire à une exposition continue à un traitement et qui disparaît après arrêt de celle-ci. Nous rapportons deux cas de lupus induit par l'isoniazide. Il s'agissait de deux femmes âgées respectivement de 30 et 35 ans. Elles présentaient un lupus induit par l'isoniazide après un et deux mois de traitement d'une tuberculose ganglionnaire. La maladie s'est manifestée par des signes articulaires, une éruption cutanée, une leucopénie et une anémie. Les anticorps antinucléaires et les anticorps antihistone étaient présents dans le sérum des deux malades. L’évolution était favorable après arrêt de l'isoniazide et une corticothérapie per os. Les médicaments antituberculeux notamment l'isoniazide sont responsables d'effets indésirables fréquents. Le lupus induit doit être évoqué lorsqu'un patient présente un tableau clinico-biologique évocateur. PMID:26430478

  8. Simulation d'ecoulements internes compressibles laminaires et turbulents par une methode d'elements finis

    NASA Astrophysics Data System (ADS)

    Rebaine, Ali

    1997-08-01

    Ce travail consiste en la simulation numerique des ecoulements internes compressibles bidimensionnels laminaires et turbulents. On s'interesse, particulierement, aux ecoulements dans les ejecteurs supersoniques. Les equations de Navier-Stokes sont formulees sous forme conservative et utilisent, comme variables independantes, les variables dites enthalpiques a savoir: la pression statique, la quantite de mouvement et l'enthalpie totale specifique. Une formulation variationnelle stable des equations de Navier-Stokes est utilisee. Elle est base sur la methode SUPG (Streamline Upwinding Petrov Galerkin) et utilise un operateur de capture des forts gradients. Un modele de turbulence, pour la simulation des ecoulements dans les ejecteurs, est mis au point. Il consiste a separer deux regions distinctes: une region proche de la paroi solide, ou le modele de Baldwin et Lomax est utilise et l'autre, loin de la paroi, ou une formulation nouvelle, basee sur le modele de Schlichting pour les jets, est proposee. Une technique de calcul de la viscosite turbulente, sur un maillage non structure, est implementee. La discretisation dans l'espace de la forme variationnelle est faite a l'aide de la methode des elements finis en utilisant une approximation mixte: quadratique pour les composantes de la quantite de mouvement et de la vitesse et lineaire pour le reste des variables. La discretisation temporelle est effectuee par une methode de differences finies en utilisant le schema d'Euler implicite. Le systeme matriciel, resultant de la discretisation spatio-temporelle, est resolu a l'aide de l'algorithme GMRES en utilisant un preconditionneur diagonal. Les validations numeriques ont ete menees sur plusieurs types de tuyeres et ejecteurs. La principale validation consiste en la simulation de l'ecoulement dans l'ejecteur teste au centre de recherche NASA Lewis. Les resultats obtenus sont tres comparables avec ceux des travaux anterieurs et sont nettement superieurs concernant les

  9. Etude aerodynamique d'un jet turbulent impactant une paroi concave

    NASA Astrophysics Data System (ADS)

    LeBlanc, Benoit

    Etant donne la demande croissante de temperatures elevees dans des chambres de combustion de systemes de propulsions en aerospatiale (turbomoteurs, moteur a reaction, etc.), l'interet dans le refroidissement par jets impactant s'est vu croitre. Le refroidissement des aubes de turbine permet une augmentation de temperature de combustion, ce qui se traduit en une augmentation de l'efficacite de combustion et donc une meilleure economie de carburant. Le transfert de chaleur dans les au bages est influence par les aspects aerodynamiques du refroidissement a jet, particulierement dans le cas d'ecoulements turbulents. Un manque de comprehension de l'aerodynamique a l'interieur de ces espaces confinees peut mener a des changements de transfert thermique qui sont inattendus, ce qui augmente le risque de fluage. Il est donc d'interet pour l'industrie aerospatiale et l'academie de poursuivre la recherche dans l'aerodynamique des jets turbulents impactant les parois courbes. Les jets impactant les surfaces courbes ont deja fait l'objet de nombreuses etudes. Par contre des conditions oscillatoires observees en laboratoire se sont averees difficiles a reproduire en numerique, puisque les structures d'ecoulements impactants des parois concaves sont fortement dependantes de la turbulence et des effets instationnaires. Une etude experimentale fut realisee a l'institut PPRIME a l'Universite de Poitiers afin d'observer le phenomene d'oscillation dans le jet. Une serie d'essais ont verifie les conditions d'ecoulement laminaires et turbulentes, toutefois le cout des essais experimentaux a seulement permis d'avoir un apercu du phenomene global. Une deuxieme serie d'essais fut realisee numeriquement a l'Universite de Moncton avec l'outil OpenFOAM pour des conditions d'ecoulement laminaire et bidimensionnel. Cette etude a donc comme but de poursuivre l'enquete de l'aerodynamique oscillatoire des jets impactant des parois courbes, mais pour un regime d'ecoulement transitoire, turbulent

  10. Appendicite aigue non compliquée: y a-t- il une place pour le traitement conservateur

    PubMed Central

    El Khader, Ahmed; Lahkim, Mohamed; El Barni, Rachid; Achour, Abdessamad

    2015-01-01

    Le but de cette étude a été d’évaluer l'efficacité de l'antibiothérapie seule dans le traitement des appendicites aigues non compliquées. C'est une étude prospective, intéressant 68 patients ayant eu une appendicite aigue simple, de confirmation radiologique, traités par l'amoxicilline associée à l'acide clavulanique pendant 10 jours. L'appendicectomie a été réalisée en cas d'aggravation ou en cas de non amélioration au bout de 48heures de traitement. Le traitement conservateur a été efficace dans 82,35% avec une résolution complète des symptômes chez 56 patients. Les 12 cas restants (17,65%) ont subit une appendicectomie. l'appendicite a été gangréneuse dans 8 cas et phlegmoneuse dans 4 cas. Cinq des 56 patients, qui ont bien évolué sous traitement conservateur, ont été réadmis et opérés pour récidive, soit 8,9%. Deux cas ont eu une appendicite compliquée. L'appendicectomie reste le traitement de référence pour l'appendicite aigue, mais le traitement antibiotique peut être proposé en première intension à des patients présentant une appendicite aigue non compliquée. PMID:26327981

  11. Nucléation, ascension et éclatement d'une bulle de champagne

    NASA Astrophysics Data System (ADS)

    Liger-Belair, G.

    2006-03-01

    People have long been fascinated by bubbles and foams dynamics, and since the pioneering work of Leonardo da Vinci in the early 16th century, this subject has generated a huge bibliography. However, only quite recently, much interest was devoted to bubbles in Champagne wines and carbonated beverages. Since the time of the benedictine monk dom Pierre Perignon (1638-1715), champagne is the wine of celebration. This fame is largely linked to the elegance of its effervescence and foaming properties. In this book, the latest results about the chemical physics behind the bubbling properties of Champagne and sparkling wines are collected and fully illustrated. The first chapter is devoted to the history of champagne and to a presentation of the tools of the physical chemistry of interfaces needed for a whole comprehension of the book. Then, the three main steps of a fleeting champagne bubble's life are presented in chronological order, that is, the bubble nucleation on the glass wall (Chap.2), the bubble ascent and growth through the liquid matrix (Chap.3), and the bursting of bubbles at the liquid surface (Chap.4), which constitutes the most intriguing, functional, and visually appealing step. L'objectif général de ce travail consacré à l'étude des processus physicochimiques liés à l'effervescence des vins de Champagne était de décortiquer les différentes étapes de la vie d'une bulle de champagne en conditions réelles de consommation, dans une flûte. Nous résumons ci-après les principaux résultats obtenus pour chacune des étapes de la vie de la bulle, depuis sa naissance sur les parois d'une flûte, jusqu'à son éclatement en surface. Nucléation À l'aide d'une caméra rapide munie d'un objectif de microscope, nous avons pu mettre à mal une idée largement répandue. Ce ne sont pas les anfractuosités de la surface du verre ou de la flûte qui sont responsable de la nucléation hétérogène des bulles, mais des particules adsorbées sur les parois du

  12. Accident D’Electrisation et Hemorragie Cerebro-Meningee : A Propos D’une Observation

    PubMed Central

    Chaibdraa, A.; Medjellakh, M.S.; Saouli, A.; Bentakouk, M.C.

    2008-01-01

    Summary L'électrisation est un évènement accidentel qui diffère des autres pathologies occasionnant des brûlures graves, à cause de ses spécificités qui traduisent d'une part la destruction du revêtement cutané, mais également les effets directs ou indirects du courant électrique sur tout tissu de l'organisme rencontré lors de son passage, en particulier le tissu nerveux. Les manifestations neurologiques centrales sont nombreuses, en relation avec les effets de l'électricité sur le parenchyme cérébral ou une lésion associée à l'électrisation. Nous rapportons l'observation d'une hémorragie cérébro-meningée survenant au 3ème jour d'une électrisation grave. Cette complication est bien documentée dans la littérature traitant des accidents d'électrisation post-foudroiement. N'ayant pas rencontré de cas similaire publié lors des accidents dus au courant industriel, nous présentons cette observation, qui soulève le problème du mécanisme physiopathologique de survenue, difficile à trancher. PMID:21991125

  13. Anévrisme de l'artère fémorale superficielle lié à une infection à salmonelle

    PubMed Central

    Mrad, Melek Ben; Hammamia, Mohammed Ben; Miri, Rim; Derbel, Bilel; Koubaa, Mohammed Ali; Ziadi, Jalel; Khayati, Adel

    2015-01-01

    Les anévrismes infectieux de l'axe fémoro-poplité sont rares et d’évolution silencieuse. Ils surviennent surtout chez les sujets immunodéprimés. Leur traitement fait appel souvent à l'exclusion chirurgicale associée ou non à un geste de revascularisation. Nous rapportons le cas d'un patient opéré pour un anévrisme de l'artère fémorale superficielle, lié à une infection à salmonelle, il a eu une résection de l'anévrysme et une revascularisation par greffe veineuse. Ce patient a été repris par la suite à deux reprise pour rupture du greffon veineux. Pour cette raison, nous étions contraints à une explantation du pontage et une ligature des 2 bouts de l'artère sans revascularisation. Malgré l'absence de revascularisation, l’évolution a été favorable sous couverture d'une une antibiothérapie adaptée. En cas d'anévrysme infectieux de l'axe fémoro-poplité par infection à salmonelle, le rétablissement de la continuité artérielle, même avec un greffon veineux, peut exposer au risque de rupture artérielle. PMID:26955409

  14. Forme pseudo tumorale d'une pneumopathie chronique à éosinophiles d’évolution fatale

    PubMed Central

    Hammoune, Nabil; El Guendouz, Faycal; Elhaddad, Siham; Janah, Hicham; Hommadi, Abdelaziz

    2015-01-01

    La pneumopathie chronique idiopathique à éosinophile est une pathologie rare, de cause inconnue, caractérisée par des opacités pulmonaires périphériques, une éosinophilie périphérique >1000/mm3 et /ou une éosinophilie alvéolaire >25%. Le diagnostic est difficile à cause de la non spécificité des signes cliniques et radiologiques. Le traitement se base essentiellement sur la corticothérapie. L’évolution est généralement favorable. Nous rapportons un cas de cette entité rare dans sa forme pseudotumorale sans hyperéosinophilie, de diagnostic tardif suite à l’étude histologique de la lobectomie chirurgicale et d’évolution fatale. PMID:26113897

  15. Localisation humérale d'une tumeur à cellules géantes récidivantes (à propos d'un cas)

    PubMed Central

    Nader, Youssef; Serghini, Issam; Koulali, Idrissi Khalid; Salahi, Hicham; Galwia, Farid

    2015-01-01

    Les auteurs rapportent un cas de localisation rare d'une tumeur à cellules géantes au niveau de la palette humérale du coude droit chez un militaire de 36 ans de sexe masculin, la radio standard montrait une image kystique ne soufflant pas la corticale. L'examen anatomo-pathologique a permis d’ établir le diagnostic et le traitement a fait appel: au début a une Exérèse chirurgicale totale et une greffe osseuse par un greffon iliaque de la totalité de la palette huméral qui s'est compliquée à 6 mois de recule d une récidive locale. PMID:25995809

  16. Caracterisation de la cohesion de l'interface AMF/polymere dans une structure deformable adaptative

    NASA Astrophysics Data System (ADS)

    Fischer-Rousseau, Charles

    Les structures déformables adaptatives (SDA) sont appelées à jouer un rôle important en aéronautique entre autres. Les alliages à mémoire de forme (AMF) sont un des candidats les plus prometteurs. Beaucoup de travail reste toutefois à faire avant que ces structures rencontrent les exigences élevées reliées à leur intégration dans un contexte aéronautique. Des travaux de recherche ont montré que la résistance à la décohésion de l’interface AMF/polymère peut être un élément limitant dans la performance des SDA. Dans ce travail, l’effet sur la résistance à la décohésion de l’interface AMF/polymère de divers traitements de surface, géométries de fil et types de polymère est évalué. La géométrie du fil est modifiée par une combinaison spécifique de laminage à froid et de recuit postdéformation qui maintient les propriétés de mémoire de forme tout en permettant de réduire l’aire de la section transversale du fil. Le traitement thermomécanique le plus prometteur est proposé. Une nouvelle méthode d’évaluation de la résistance à la décohésion est développée. Plutôt que de tester les fils en arrachement et de mesurer la force maximale, les tests en contraction sont basés sur la capacité des fils d’AMF à se contracter s’ils ont été encastrés dans un état tiré et qu’ils sont chauffés par effet Joule. L’hypothèse qu’on pose est que ces tests sont une meilleure approximation des conditions rencontrées dans une SDA, où les fils se contractent plutôt qu’ils sont arrachés par une force externe à la structure. Bien qu’une décohésion partielle ait été observée pour tous les échantillons, l’aire de la surface où il y a décohésion tait plus grande pour les échantillons avec une pré-déformation plus grande. Le front de décohésion a semblé cesser de progresser après les cycles de chauffage initiaux lorsque la vitesse de chauffage était faible. Un modèle numérique simulant la

  17. Déclenchement du travail à terme par le misoprostol: expérience d'une maternité tunisienne

    PubMed Central

    Ouerdiane, Nadia; Tlili, Nihel; Othmani, Kaouther; Daaloul, Walid; Masmoudi, Abdelwaheb; Hamouda, Sonia Ben; Bouguerra, Badreddine

    2016-01-01

    Evaluer l'efficacité et l'innocuité de l'utilisation du misoprostol par voie vaginale pour le déclenchement du travail à terme. Etude prospective réalisée au service de gynécologie obstétrique B de l'hôpital Charles Nicolle de Tunis sur une durée de 4 mois. La population sélectionnée concernait les patientes à terme devant bénéficier d'une maturation cervicale. Le misoprostol à la dose de 50 µg par voie vaginale toutes les 12 h était utilisé. Les paramètres étudiés étaient les anomalies contractiles, les anomalies du RCF, le mode d'accouchement, le délai d'accouchement et l’état néonatal. 44 patientes ont bénéficié d'une maturation cervicale par misoprostol. Le terme moyen était de 40 SA. Le taux de nullipare était de 23/44 (52%). Le taux d'accouchement par voie basse était de 31/44 (70.4%). 84% des patientes ont reçu une seule dose de misoprostol. Les anomalies du RCF ont été notées dans 14/44 (32%). Le taux de liquides méconiaux était de 12/44 (27%). Un score d'Apgar à 5 mn inférieur à 7 était noté chez 7/44 (16%). Un cas de rupture utérine était survenue chez une primipare et ce après une seule prise de misoprostol. Nos résultats sont décevants en raison de la survenue d'une rupture utérine et d'une morbidité néonatale importante. D'autres études prospectives multicentriques restent utiles pour mieux s'assurer de l'efficacité mais surtout de l'innocuité du misoprostol à dose faible pour le déclenchement du travail à terme. PMID:27583092

  18. Une forme exceptionnelle de la luxation perilunaire du carpe

    PubMed Central

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

    2014-01-01

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

  19. Myélome multiple survenant au cours d'une Fièvre Méditerranéenne Familiale

    PubMed Central

    Salem, Bouomrani; Afef, Farah; Nadia, Bouassida; Nabil, Ayadi; Zouhir, Bahloul; Maher, Béji

    2013-01-01

    L'objectif de ce travail est de rapporter une observation particulière de myélome multiple survenant au cours d'une maladie périodique. Il s'agit d'un patient tunisien de 53 ans suivi depuis le jeune âge pour maladie périodique dont le diagnostic était confirmé par l’étude génétique montrant l'homozygotie pour la mutation M694V du gène MEFV, fut admis pour exploration d'une douleur avec tuméfaction fessière droite récente. Les explorations biologiques et radiologiques ont permis de retenir le diagnostic d'un myélome multiple de type IgA à chaînes légères kappa stade III B, associé à une volumineuse localisation plasmocytaire très agressive de l'aile iliaque droite envahissant les structures musculaires avoisinantes. Notre observation, qui à notre connaissance est la deuxième signalant une telle association, se distingue par sa survenue brutale, sa progression rapide et le caractère très agressif de l'hémopathie. PMID:24255729

  20. Tuméfaction du muscle pectoral révélant une tuberculose musculaire isolée

    PubMed Central

    Hayoun, Sohaib; Ouazzani, Hanane El; Habibi, Bouchra; Belhabib, Salwa; Souhi, Hicham; Rhorfi, Ismail Abderahmane; Abid, Ahmed

    2017-01-01

    La tuberculose des parties molles représente l’une des formes rares de la tuberculose extra pulmonaire, la localisation musculaire isolée est par-ailleurs exceptionnelle. Nous rapportant une observation médicale originale, une tuberculose musculaire isolée intéressant le muscle grand pectoral chez un jeune patient immunocompétent. Le diagnostic a reposé essentiellement sur l’histologie. L’évolution été favorable sous traitement anti bacillaire seul. Ce cas rare est présenté avec revue de littérature. PMID:28761620

  1. L'endométriose pariétale cicatricielle après césarienne: une entité rare

    PubMed Central

    El Fahssi, Mohammed; Lomdo, Massama; Bounaim, Ahmed; Ali, Abdelmounaim Ait; Sair, Khalid

    2016-01-01

    L'endométriose de la paroi est une entité clinique rare, dont la physiopathologie demeure imprécise. Elle survient le plus souvent après une intervention chirurgicale gynécologique ou obstétricale. Nous rapportons le cas d'une patiente présentant une douleur cyclique, au niveau de la cicatrice de césarienne, Avec à l'examen clinique une masse de 5cm localisée au niveau de la fosse iliaque droite. la tomodensitométrie montre une masse de densité tissulaire de 45mm de grand axe. D'où la décision d'excision large de la lésion dont l’étude anatomopathologique confirme le diagnostic d'endométriose pariétale. Les suites postopératoires étaient simples avec un recul de 20 mois sans récidive de la masse ni de la douleur. A travers notre cas, nous insisterons sur les caractéristiques de cette pathologie, ce qui permettra au praticien de comprendre l'intérêt du diagnostic et de la prise en charge précoce de cette affection ainsi que la possibilité de sa prévention au cours de chaque chirurgie gynécologique ou obstétricale. PMID:27642418

  2. Une version franco-canadienne de la Physiotherapy Evidence Database (PEDro) Scale : L'Échelle PEDro

    PubMed Central

    Laroche, Chantal; Sutton, Anne; Guitard, Paulette; King, Judy; Poitras, Stéphane; Casimiro, Lynn; Tremblay, Manon; Cardinal, Dominique; Cavallo, Sabrina; Laferrière, Lucie; Grisé, Isabelle; Marshall, Lisa; Smith, Jacky R.; Lagacé, Josée; Pharand, Denyse; Galipeau, Roseline; Toupin-April, Karine; Loew, Laurianne; Demers, Catrine; Sauvé-Schenk, Katrine; Paquet, Nicole; Savard, Jacinthe; Tourigny, Jocelyne; Vaillancourt, Véronique

    2015-01-01

    RÉSUMÉ But : Effectuer une traduction franco-canadienne de la PEDro scale sous l'appellation proposée d'Échelle PEDro et examiner la validité de son contenu. Méthodologie : Nous avons utilisé une approche modifiée de la méthodologie de validation transculturelle de Vallerand. Une traduction renversée parallèle de la PEDro scale a d'abord été effectuée à la fois par des traductrices professionnelles et des chercheurs cliniciens. Ensuite, un premier comité d'experts (P1) a examiné les versions traduites et a créé la première version expérimentale de l'Échelle PEDro. Cette version a été évaluée par un deuxième comité d'experts (P2). Finalement, 32 chercheurs cliniques ont évalué cette deuxième version expérimentale de l'Échelle PEDro à l'aide d'une échelle de clarté (étendue de 5 points) et ont proposé les modifications finales. Résultats : Pour les différents énoncés de la version finale de l'Échelle PEDro, les moyennes sur l'échelle de clarté montrent un niveau élevé puisqu'elles varient entre 4,0 et 4,7 sur un score maximal de 5 points. Conclusion : Les quatre étapes rigoureuses du processus ont permis de produire une version franco-canadienne valide de l'Échelle PEDro. PMID:26839449

  3. Grossesses extra utérines successives et bilharziose tubaire chez une touriste française

    PubMed Central

    Laroche, Justine; Mottet, Nicolas; Malincenco, Marianna; Gay, Catherine; Royer, Pierre Yves; Riethmuller, Didier

    2016-01-01

    La bilharziose est la seconde endémie parasitaire mondiale et ses atteintes génito urinaires sont bien décrites. Les grossesses ectopiques (GEU) sur obstruction tubaire par les œufs de bilharziose sont rapportées dans les populations africaines. La bilharziose affecte aussi les voyageurs mais l'atteinte de l'appareil génital féminin est plus rare. Nous rapportons un cas exceptionnel de deux GEU successives sur bilharziose tubaire chez une patiente d'origine Française, sept ans après un voyage touristique au Mali, la première découverte sur pièce de salpingectomie et la seconde ayant nécessité une salpingotomie controlatérale avec une injection de méthotrexate, deux mois plus tard. PMID:27200124

  4. Insuffisance rénale aigüe: présentation rare d’une maladie d’Addison

    PubMed Central

    Salhi, Houda

    2016-01-01

    La maladie d’Addison est une pathologie rare, qui se manifeste fréquemment par des signes cliniques non spécifiques. Ce qui peut causer un retard diagnostic et thérapeutique. Cette maladie peut se présenter comme un tableau d’insuffisance rénale aigue. Nous rapportons le cas d’un patient présentant une maladie d’Addison qui a été pris en charge initialement comme une insuffisance rénale aigue secondaire à un myélome multiple et dont le diagnostic a été redressé par la suite. Le patient s’est spectaculairement amélioré après mis en place de traitement par réhydratation par voie intraveineuse; hydrocortisone injectable. PMID:27800088

  5. Métastase pleurale et pulmonaire d’une polyadénofibromatose dégénéréé: à propos d’un cas

    PubMed Central

    El Hachimi, Kawtar; Benjelloun, Hanane; Zaghba, Nahid; Yassine, Najiba

    2017-01-01

    La polyadénofibromatose ou l’adénofibromatose est définie par la présence d’au moins 3 adénofibromes, uni ou bilatéraux atteignant une taille importante responsable de troubles trophiques. Nous rapportons une observation colligée au service des maladies respiratoires du Centre Hospitalier Universitaire Ibn Rochd de Casablanca. Il s’agit d’une patiente âgée de 46ans, suivie depuis l’âge de 30 ans pour une adénofibromatose bilatérale opérée à 4 reprises. Suite à un bilan préopératoire d’une mastectomie bilatérale, une radio du thorax a été réalisée objectivant un hémithorax droit opaque avec refoulement des éléments du médiastin. L’examen clinique retrouvait un syndrome d’épanchement liquidien de l’hémithorax droit et une adénopathie cervicale sus claviculaire gauche. La ponction biopsie pleurale confirmait la localisation pleurale d’un carcinome peu différencié et invasif compatible avec une origine mammaire. La bronchoscopie après évacuation pleurale objectivait un aspect infiltré de tout l’arbre bronchique, dont les biopsies concluaient au même résultat anatomopathologique. Le traitement préconisé était une polychimiothérapie. L’évolution était marquée par l’apparition de métastases hépatiques. A travers cette observation, nous concluons que les adénofibromes nécessitent une surveillance régulière vu le risque de dégénérescence vers le cancer du sein qui est une cause fréquente de métastases pleuropulmonaires. PMID:29515733

  6. Conception, fabrication et validation d'une presse a injection basse pression pour le procede des poudres metalliques =

    NASA Astrophysics Data System (ADS)

    Lamarre, Simon G.

    Le moulage par injection a basse pression de poudre metallique est une technique de mise en forme de pieces de formes complexes. La poudre metallique est melangee avec des polymeres basse viscosite (ex. : cire) pour former un melange homogene a une temperature superieure a la temperature de fusion des polymeres. Pour faciliter l'injection dans la cavite du moule, la composition des melanges est ajustee pour diminuer la viscosite. D'une part, les melanges peu visqueux possedent une bonne moulabilite. D'autre part, le phenomene de la segregation se manifeste rapidement avec les melanges peu visqueux. Les machines commerciales sont munies d'un canal d'injection et d'une valve qui relient le reservoir de melange et la cavite du moule. Le melange reste stationnaire dans ces composantes entre deux sequences d'injection, ce qui le rend propice a la segregation. Plusieurs brevets tentent de resoudre ce probleme en utilisant des pompes et des canaux de recirculation. Ces composantes sont difficiles a nettoyer en raison de leur complexite. Une machine a injection basse pression a ete concue et fabriquee pour l'etude de l'aptitude au moulage des melanges de tres faible viscosite (ex. : 0.1 Pa˙s), qui tient compte du phenomene de segregation et des contraintes de nettoyage. Un piston d'injection puise le volume desire d'un reservoir. Ensuite, un mouvement lateral cisaille le melange a l'intersection entre le reservoir et le cylindre et bouche l'orifice de sortie du reservoir. Le cylindre est degage et peut recevoir le moule. A la suite de l'injection, le piston retourne a la position du reservoir et entre dans son orifice de sortie. Le melange residuel est retourne dans le reservoir, melange et desaere a nouveau. L'appareil a ete valide par des essais d'injectabilite avec un melange de poudre d'acier inoxydable et de liants a basse viscosite. Des essais d'injection ont montre que le melange contenant l'acide stearique a parcouru la plus grande distance dans le moule de forme

  7. Variabilite temporelle des naines T et construction d'une camera infrarouge a grand champ

    NASA Astrophysics Data System (ADS)

    Artigau, Etienne

    Le travail de thèse décrit ici se divise en deux sections distinctes: la première porte sur une étude de la variabilité temporelle des naines T et la seconde sur la construction et les performances de la Caméra PAnoramique Proche InfraRouge (CPAPIR). Les naines brunes sont des objets qui se forment comme les étoiles, lors de l'effondrement gravitationnel d'un nuage de gaz moléculaire, mais dont la masse est trop faible pour leur permettre d'entretenir des réactions de fusion nucléaire. Environ 70% des naines brunes de type L, qui ont des températures comprises entre 2200 K et 1500 K, présentent une variabilité temporelle dont les mécanismes exacts font toujours l'objet de débats. Nous avons étendu la recherche de variabilité temporelle aux naines brunes ayant des températures inférieures à ~1500 K et qui présentent les signatures du méthane, soit les naines T. Nos observations menées à l'Observatoire du mont Mégantic montrent qu'une fraction importante des naines T sont variables à 1.2 mm et 1.6 mm à des niveaux allant de 17 mmag à 53 mmag RMS. Les propriétés photométriques de cette variabilité sont consistantes avec une évolution de la couverture de nuages de poussière à la surface de plusieurs naines T. Des observations complémentaires menées en spectroscopie au télescope Canada-France-Hawaii montrent, pour une naine T, une variabilité spectroscopique dans le proche infrarouge qui est aussi consistante avec l'évolution de tels nuages de poussière. CPAPIR est une caméra infrarouge con=E7ue pour être utilisée à l'Observatoire du mont Mégantic. Elle possède un champ de 30' × 30', soit le plus grand champ de vue parmi les caméras infrarouges astronomiques actuellement en service. CPAPIR est équipé d'un détecteur de type Hawaii-II sensible de 0.8 mm à 2.4 mm avec 2048×2048 pixels. L'optique cryogénique de CPAPIR comprend 8 lentilles cryogéniques et 10 filtres disposés dans deux roues à filtres. Les observations

  8. Virtual Mobility in Higher Education. The UNED Campus Net Program

    ERIC Educational Resources Information Center

    Aguado, Teresa; Monge, Fernando; Del Olmo, Alicia

    2014-01-01

    We present the UNED Virtual Mobility Campus Net Program, implemented since 2012 in collaboration with European and Latin American universities. Program's objectives, participating institutions, procedures, and evaluation are exposed. Virtual mobility is understood as a meaningful strategy for intercultural learning by studying an undergraduate or…

  9. Pneumonie organisée révélatrice d'une polymyosite

    PubMed Central

    Ben Saad, Ahmed; Joobeur, Samah; Rouetbi, Naceur; Mhamed, Saousen Cheikh; Skhiri, Néji; Mribah, Hathami; El Kamel, Ali

    2014-01-01

    Les polymyosites (PM) sont des connectivites très rares, d’étiologie inconnue, dotées d'un grand polymorphisme clinique et évolutif. Elles peuvent être associées à d'autres manifestations viscérales notamment pulmonaires telles que la pneumopathie interstitielle. Ces complications respiratoires sont souvent associées à un taux de mortalité élevé. Les cas de pneumonie organisée révélatrice de polymyosite sont rarement rapportés dans la littérature et de description récente. Nous rapportons l'observation d'une patiente âgée de 53 ans qui a présenté, 14 mois après avoir porter le diagnostic d'une pneumonie organisée, des myalgies diffuses, un ‘dème des membres inférieurs et une élévation des enzymes musculaires. La biopsie musculaire a confirmé le diagnostic de la myosite. L’évolution était favorable sous corticothérapie. Le traitement de la PO associée au PM n'est pas clairement établi. La corticothérapie constitue le traitement de première intention. PMID:25722789

  10. Evaluation d’une grille de supervision des laboratoires des leishmanioses cutanées au Maroc

    PubMed Central

    El Mansouri, Bouchra; Amarir, Fatima; Hajli, Yamina; Fellah, Hajiba; Sebti, Faiza; Delouane, Bouchra; Sadak, Abderrahim; Adlaoui, El Bachir; Rhajaoui, Mohammed

    2017-01-01

    Introduction Afin d’évaluer une grille de contrôle standardisée de laboratoire de diagnostic des leishmanioses, comme nouveau outil de supervision. Méthodes Un essai pilote a été pratiqué sur sept laboratoires provinciaux, appartenant à quatre provinces au Maroc, en suivant l’évolution de leurs performances tous les deux ans, entre l’année 2006 et 2014. Cette étude détaille la situation des laboratoires provinciaux avant et après la mise en œuvre de la grille de supervision. Au total vingt et une grille sont analysées. Résultats En 2006, les résultats ont montré clairement une insuffisance des performances des laboratoires: besoin en formation (41.6%), personnel pratiquant le prélèvement cutané (25%), pénurie en matériels et réactifs (65%), gestions documentaire et local non conformes (85%). Différentes actions correctives ont été menées par le Laboratoire National de Référence des Leishmanioses (LNRL) durant la période d’étude. En 2014, le LNRL a enregistré une nette amélioration des performances des laboratoires. Les besoins en matière de formation, qualité du prélèvement, dotation en matériels et réactifs ont été comblés et une coordination efficace s’est établie entre le LNRL et les laboratoires provinciaux. Conclusion Ceci montre l'efficacité de la grille comme outil de supervision de grande qualité, et comme pierre angulaire de tout progrès qui doit être obtenu dans les programmes de lutte contre les leishmanioses. PMID:29187922

  11. La prise en charge d’une clientèle

    PubMed Central

    Roy, Andréanne; Breton, Mylaine; Loslier, Julie

    2016-01-01

    Résumé Objectif Analyser les facteurs qui incitent les médecins de famille nouvellement autorisés à faire de la prise en charge d’une clientèle en première ligne. Type d’étude Devis mixte séquentiel : questionnaire en ligne auto-administré auprès de médecins de famille, suivi d’entrevues individuelles. Contexte La Montérégie, qui est la deuxième région la plus populeuse du Québec, et qui présente des zones rurales et urbaines. Participants Tous les médecins de famille détenant un poste en Montérégie et ayant moins de 10 années d’expérience ont été sollicités, soit 366 médecins. Parmi eux, 118 ont complété le questionnaire en ligne (taux de réponse de 32,2 %). Parmi les répondants, 10 médecins ayant des profils de prise en charge variés ont été sélectionnés pour les entrevues individuelles. Principaux paramètres à l’étude Le pourcentage de temps de travail consacré à la prise en charge, analysé en parallèle avec différents facteurs facilitants et barrières à la prise en charge aux niveaux contextuel, organisationnel, du médecin de famille et de la clientèle. Résultats Les principaux facteurs facilitant la prise en charge sont la relation médecin-patient, l’intérêt pour les activités cliniques liées à la prise en charge, les modèles de rôles positifs, la collaboration avec une infirmière et l’accès adéquat aux ressources, notamment en santé mentale. Les principales barrières sont l’ampleur des tâches administratives, l’intérêt pour une pratique polyvalente, l’expérience négative de la prise en charge lors de la formation, un sentiment n’inaptitude à l’égard de la prise en charge, la lourdeur de la clientèle et le manque de soutien en début de pratique. Conclusion Certaines pistes de solution pour inciter les nouveaux médecins de famille à prendre en charge une clientèle sont proposées. Des points d’amélioration au niveau de la formation médicale, du soutien

  12. Paraplégie compliquant une plaie abdominale antérieure par arme blanche

    PubMed Central

    Elahmadi, Brahim; Awab, Almahdi; El Moussaoui, Rachid; El Hijri, Ahmed; Azzouzi, Abderrahim; Alilou, Mustapha

    2015-01-01

    Les traumatismes médullaires sont des complications rares des plaies abdominales antérieures par arme blanche. Son diagnostic est difficile parfois retardé. L'imagerie par résonance magnétique reste l'examen de choix. Le traitement dépend du tableau clinique et de la gravité de la souffrance médullaire. Le pronostic est corrélé à l’étendue et à la nature de la lésion médullaire. Nous rapportons un cas exceptionnel d'un traumatisme médullaire chez une patiente victime d'une plaie abdominale antérieure par arme blanche. PMID:25995808

  13. Une cryptococcose disséminée compliquant un traitement par prednisone et azathioprime d'un pemphigus vulgaire

    PubMed Central

    Wafa, Ammouri; Hicham, Harmouche; Yassir, Afifi; Zoubida, Tazi Mezalek; Mohamed, Adnaoui; Mohamed, Aouni; Amine, Hassani; Abdelaziz, Maaouni

    2011-01-01

    L'infection à cryptocoque est une complication redoutable chez les patients traités par immunosuppresseurs et dont l’évolution peut être rapidement fatal en cas de retard diagnostic. Nous rapportons le cas d'une patiente âgée de 70 ans, ayant des antécédents de pemphigus vulgaire traité par prednisone et azathioprime et admise dans le service de médecine Interne pour des nodules sous cutanés atypiques. Le diagnostic retenu était celui d'une cryptococcose disséminée. L’évolution était rapidement fatale malgré le traitement antifongique. PMID:22187617

  14. Choc hémorragique suite à une ponction biopsie rénale (PBR): à propos d'un cas

    PubMed Central

    El Hammoumi, Jalal; Boukatta, Brahim; Houari, Nawfal; Elbouazzaoui, Abderrahim; Sbai, Hicham; Kanjaa, Nabil

    2015-01-01

    La ponction biopsie rénale (PBR) est un examen indispensable en néphrologie mais à risque de complications graves surtout hémorragique. Nous rapportons l'observation d'un patient âgé de 27 ans ayant bénéficié d'une PBR pour un diagnostic étiologique d'une insuffisance rénale aigue, l’évolution après la biopsie a été marquée par l'installation d'un choc hémorragique d'où la prise en charge en réanimation avec une néphrectomie d'hémostase. PMID:26848362

  15. Hémophilie B mineure révélée par une hémorragie cérébrale: à propos d'un cas

    PubMed Central

    Naji, Abdelhalim; Rkain, Maria; Amrani, Rim; Benajiba, Noufissa

    2015-01-01

    L'hémorragie intracrânienne (HIC) du nouveau-né à terme est une pathologie rare, leur prévalence est estimée à 2% des naissances vivantes. Les manifestations cliniques sont variables et non spécifique. Les causes d'HIC sont multiples et souvent intriquées, les mécanismes physiopathologiques principaux sont la dysrégulation du débit cérébral, une obstruction des vaisseaux ou une coagulation intravasculaire; ou une lésion directe par traumatisme. Nous rapportons le cas d'un nourrisson d'un mois qui a été admis dans notre service pour prendre en charge des convulsions associées à une pâleur cutanéomuqueuse, suite à laquelle l'examen biologique a mis fortuitement en faveur une hémophilie mineure sur une maladie hémorragique tardive. PMID:26491519

  16. Possibilité d'une nouvelle technologie de traitement des minerais de fer de l'Ouenza par radiométrie

    NASA Astrophysics Data System (ADS)

    Idres, A.; Bounouala, M.

    2005-05-01

    En l'absence d'une technologie fiable de traitement des haldes de minerais de fer, les caractéristiques minéralogiques et chimiques complexes et les effets néfastes des résidus miniers posent réellement un problème environnemental. A cet effet, une étude minéralogique et chimique du minerai de fer a été menée en utilisant des techniques multiples (microscopie optique, DRX, FX, MEB). En tenant compte de la nature des résidus, des échantillons représentatifs ont été testés par séparation radiométrique. Plusieurs paramètres ont été caractérisés tels que la vitesse de la bande transporteuse, le temps d'émission des rayons gamma et la granulométrie d'alimentation du procédé. Les résultats ainsi obtenus par cette méthode de séparation sont très significatifs en récupération et en teneur fer. Cependant, cette nouvelle technologie permet d'une part une meilleure valorisation des minerais de fer et d'autre part une réduction du tonnage stocké sur le carreau de la mine.

  17. Une alternative au cobalt pour la synthese de nanotubes de carbone monoparoi par plasma inductif thermique

    NASA Astrophysics Data System (ADS)

    Carrier, Jean-Francois

    Les nanotubes de carbone de type monoparoi (C-SWNT) sont une classe recente de nanomateriaux qui ont fait leur apparition en 1991. L'interet qu'on leur accorde provient des nombreuses proprietes d'avant-plan qu'ils possedent. Leur resistance mecanique serait des plus rigide, tout comme ils peuvent conduire l'electricite et la chaleur d'une maniere inegalee. Non moins, les C-SWNT promettent de devenir une nouvelle classe de plateforme moleculaire, en servant de site d'attache pour des groupements reactifs. Les promesses de ce type particulier de nanomateriau sont nombreuses, la question aujourd'hui est de comment les realiser. La technologie de synthese par plasma inductif thermique se situe avantageusement pour la qualite de ses produits, sa productivite et les faibles couts d'operation. Par contre, des recherches recentes ont permis de mettre en lumiere des risques d'expositions reliees a l'utilisation du cobalt, comme catalyseur de synthese; son elimination ou bien son remplacement est devenu une preoccupation importante. Quatre recettes alternatives ont ete mises a l'essai afin de trouver une alternative plus securitaire a la recette de base; un melange catalytique ternaire, compose de nickel, de cobalt et d'oxyde d'yttrium. La premiere consiste essentiellement a remplacer la proportion massique de cobalt par du nickel, qui etait deja present dans la recette de base. Les trois options suivantes contiennent de nouveaux catalyseurs, en remplacement au Co, qui sont apparus dans plusieurs recherches scientifiques au courant des dernieres annees: le dioxyde de zircone (ZrO2), dioxyde de manganese (MnO2) et le molybdene (Mo). La methode utilisee consiste a vaporiser la matiere premiere, sous forme solide, dans un reacteur plasma a haute frequence (3 MHz) a paroi refroidi. Apres le passage dans le plasma, le systeme traverse une section dite de "croissance", isolee thermiquement a l'aide de graphite, afin de maintenir une certaine plage de temperature favorable a la

  18. Evolution des syndromes électrocliniques chez des jumeaux dizygotes: de l'enfance à l'adolescence, à propos d'une observation

    PubMed Central

    Bugeme, Marcellin; Kadiebwe, David Mulumba; Kakoma, Placide Kambola; Mukuku, Olivier

    2015-01-01

    Les syndromes électrocliniques ont une prédisposition génétique très variable et leur évolution de l'enfance vers l'adolescence ou l’âge adulte n'est pas bien définie. Nous rapportons ici une observation mettant en jeu deux jumeaux dizygotes âgés de 19 ans ayant présenté un phénotype épileptique différent pendant l'enfance (épilepsie avec absences myocloniques et épilepsie-absence de l'enfant) mais une concordance phénotypique (épilepsie à crises généralisées tonico-cloniques prédominantes) au cours de l'adolescence. Cette observation plaide en faveur d'une implication génétique dans l’évolution de ces syndromes électrocliniques. PMID:26090006

  19. Fistule vésico-vaginale néoplasique secondaire à une tumeur de vessie: une entité rare

    PubMed Central

    Bagayogo, Tidiani; Jakhal, Nabil; Slaoui, Amine; Ziouziou, Imad; Karmouni, Tariq; El Khader, Khalid; Koutani, Abdelatif; Andaloussi, AhmedI bn Attya

    2016-01-01

    La fistule vésico-vaginale sur tumeur de vessie est extrêmement rare. Nous rapportons un cas de fistule vésico-vaginale (FVV) néoplasique chez une patiente de 54 ans, ménopausée, sans antécédent chirurgical ou de traumatisme obstétrical récent. La biopsie des berges de la fistule est revenue en faveur d’un carcinome urothélial. A la lumière de cette observation, nous discutons les formes étiologiques ainsi que les différentes stratégies thérapeutiques respectives des FVV. PMID:28250883

  20. Etiologies des hypertensions artérielles endocrines: à propos d'une série de cas

    PubMed Central

    Bouznad, Naima; El Mghari, Ghizlane; El Ansari, Nawal

    2016-01-01

    Les hypertensions artérielles (HTA) d'origine endocrine restent une cause rare d'HTA, sa prévalence globale n'excède pas 4% des hypertendus. L'intérêt de la recherche des HTA endocrines réside dans la gravité de certaines formes parfois mortelles et le caractère potentiellement curable et réversible de ces HTA. Le but du travail est de déterminer le profil clinique, para clinique, étiologique et thérapeutique des HTA secondaires d'origine endocrine chez les patients suivis au service d'endocrinologie au CHU Mohamed IV à Marrakech. Il s'agit d'une étude descriptive prospective s’étalant sur une période de 4 ans incluant 45 patients ayant une HTA endocrinienne. La moyenne d’âge est de 44,89 ans, avec une nette prédominance du sexe féminine (sexe ratio de 0,49). Les étiologies des HTA endocrines étaient dominées par le phéochromocytome (17 cas), l'hypercorticisme (11 cas) et l'acromégalie (8 cas). L'HTA était paroxystique dans 24,4%. Elle était d'emblée sevère classée grade 3 dans 40% des cas. L'HTA a été compliquée de cardiopathie dans 24% des cas et de néphropathie dans 20% des cas. Le traitement curatif a permis une guérison de l'HTA chez 60% (27 cas). Le diagnostic des HTA secondaires endocrines est parfois difficile du fait de l'absence de spécificité clinique. Il n'est pas exceptionnel que l'HTA soit l'unique manifestation de la maladie. Dans notre travail nous notons le caractère paroxystique et sévère de l'HTA. Le caractère éventuellement curable des HTA endocrines, dans plus des deux tiers des cas, fait qu'il est important de la dépister devant toute HTA sévère, résistante au traitement, ou en présence de signes cliniques, biologiques ou radiologiques évocateurs. PMID:27303586

  1. Validation de la traduction française de la SURPS pour une population d’adolescents québécois

    PubMed Central

    Castonguay-Jolin, Laura; Perrier-Ménard, Eveline; Castellanos-Ryan, Natalie; Parent, Sophie; Vitaro, Frank; Tremblay, Richard E; Garel, Patricia; Séguin, Jean R; Conrod, Patricia J

    2013-01-01

    Objectif La Substance Use Risk Profile Scale (SURPS) est un instrument de dépistage des caractéristiques de personnalité qui représentent un risque pour le développement d’une consommation problématique de substances. La SURPS comporte 23 items évaluant 4 dimensions et permet aux intervenants en santé mentale de mieux cibler la prévention. La SURPS a été validée au Canada anglais, au Royaume-Uni, en Chine et au Sri Lanka; l’objectif de cette étude est de valider une traduction française de la SURPS pour des adolescents francophones québécois, en plus d’en tester la sensibilité dans une population clinique. Méthode Deux cent deux jeunes de 15 ans d’un échantillon communautaire ont répondu à la SURPS et à des mesures de la personnalité et de l’utilisation de substances. La cohérence interne, la solution factorielle et la validité concomitante de l’échelle ont été évaluées. Quarante adolescents (âge moyen de 15,7 ans) présentant un diagnostic psychiatrique ont également répondu à la SURPS et les scores ont été comparés aux normes de l’échantillon communautaire. Résultats La traduction française de la SURPS démontre une bonne cohérence interne ainsi qu’une solution factorielle à 4 facteurs semblable à la version originale. Ses 4 souséchelles ont une bonne validité concomitante. De plus, 3 de ses souséchelles sont corrélées avec des mesures relatives à la consommation de substances psychoactives. Finalement, 95 % des participants de l’échantillon clinique ont été identifiés à risque selon les scores limites de la SURPS. Conclusion La version française de la SURPS paraît être une mesure valide et sensible pouvant être utilisée auprès d’une population adolescente, québécoise et francophone. PMID:24099502

  2. Une complication rare des léiomyomes utérins: hémopéritoine massif par rupture de varices

    PubMed Central

    Ymele, Florent Fouelifack; Tsuala, Jovanny Fouogue; Fouedjio, Jeanne Hortence; Nangué, Charlette; De Kayo, Caroline Kayo; Dobgima, Pisoh Walter; Mbu, Robinson Enoh

    2013-01-01

    Les léiomyomes utérins sont des causes exceptionnelles d'hémopéritoine. Nous rapportons ici le cas d'une femme de 46 ans nullipare, en instance d'une hystérectomie totale indiquée pour utérus polymyomateux symptomatique. Elle a été opérée en urgence pour hémopéritoine aigu et massif compliqué de choc hémorragique. L'origine de l'hémopéritoine était la rupture spontanée d'une varice du léiomyome. Quoique rare l'éventualité d'un hémopéritoine causé par un fibrome utérin devrait être évoquée devant tout abdomen aigu spontané chez une femme en âge de procréer. La présence de varices sur les fibromes augmenterait le risque d'hémorragie spontanée. PMID:23717724

  3. Approche aux soins en milieu communautaire à des adultes ayant une déficience développementale

    PubMed Central

    Osmun, W.E.; Chan, Nelson; Solomon, Robert

    2015-01-01

    Résumé Objectif Passer en revue les obligations d’ordre médical, éthique et juridique dans les soins aux adultes ayant une déficience développementale (DD) qui vivent dans la communauté. Sources des données Des recherches ont été faites dans Google et MEDLINE à l’aide des mots disabled, disability, vulnerable et community. Les lois pertinentes ont fait l’objet d’un examen. Message principal Le traitement d’un patient ayant une DD varie en fonction de facteurs comme la pathogenèse du problème actuel du patient, ses affections concomitantes, la gravité de ses déficiences et ses soutiens sociaux habituels. Bien que l’on s’entende sur les bienfaits du transfert des soins institutionnels vers des soins communautaires pour les patients ayant une DD, il s’est révélé difficile de leur dispenser des soins de grande qualité en milieu communautaire. Par ailleurs, il existe peu de travaux de recherche sur les façons d’offrir efficacement des soins aux adultes ayant une DD. En tant que professionnels des soins primaires, les médecins de famille sont souvent le premier point de contact pour les patients et sont à la fois responsables de la coordination et de la continuité des soins. Compte tenu de l’importance accrue accordée aux soins préventifs et à la détection précoce des maladies, la participation active du patient revêt aussi une grande importance. Les valeurs et les objectifs du patient sont des éléments essentiels à prendre en compte, même s’ils vont à l’encontre de la bonne santé du patient ou des propres valeurs du clinicien. Les lois s’appliquant aux personnes vulnérables varient d’une province à l’autre. Par conséquent, l’obligation de signaler des mauvais traitements suspectés pourrait différer selon que la personne vulnérable habite dans un centre de soins ou la communauté, que la personne qui soupçonne le comportement abusif est un fournisseur de services ou un professionnel de la santé ou

  4. Strategy for earth explorers in global earth sciences

    NASA Technical Reports Server (NTRS)

    1988-01-01

    The goal of the current NASA Earth System Science initiative is to obtain a comprehensive scientific understanding of the Earth as an integrated, dynamic system. The centerpiece of the Earth System Science initiative will be a set of instruments carried on polar orbiting platforms under the Earth Observing System program. An Earth Explorer program can open new vistas in the earth sciences, encourage innovation, and solve critical scientific problems. Specific missions must be rigorously shaped by the demands and opportunities of high quality science and must complement the Earth Observing System and the Mission to Planet Earth. The committee believes that the proposed Earth Explorer program provides a substantial opportunity for progress in the earth sciences, both through independent missions and through missions designed to complement the large scale platforms and international research programs that represent important national commitments. The strategy presented is intended to help ensure the success of the Earth Explorer program as a vital stimulant to the study of the planet.

  5. Cause rare d’insuffisance rénale aigue: géant calcul de vessie chez une jeune femme

    PubMed Central

    Mohammed, Bounoual; Mustapha, Ahsaini; Karim, Tazi; Hamid, Azelmad; Mohammed, Alila; Soufiane, Mellas; eddine, El Ammari Jalal; Fadl, Tazi Mohammed; Jamal, El Fassi Mohammed; Hassan, Farih Moulay

    2018-01-01

    Géant calcul de vessie se définit par un poids supérieur à 100 g, c'est une pathologie rare chez la femme, environ 2%. La localisation vésicale ne dépasse pas 5% de l'ensemble des voies urinaires. Chez la femme l'apparition de calcul de vessie est souvent secondaire à un facteur prédisposant notamment un corps étranger intra vésical, vessie neurogene, les infections urinaires à répétition, ATCDS de chirurgie de l'incontinence urinaire d'effort. Mais on retrouve des calculs de vessie sans causes évidentes dits calculs primaires idiopathiques. On rapporte un cas d'une jeune patiente de 31 ans avec un géant calcul de vessie qui a retenti sur le haut appareil urinaire entrainant une insuffisance rénale aigue. La patiente a bénéficié initialement d'un drainage de haut appareil urinaire par des néphrostomies bilatérales puis elle a bénéficié d'une cystolithotomie à ciel ouvert d'un gros calcul de vessie. Un bilan étiologique a été demandé pourtant n'a pas identifié de cause évidente. PMID:29632626

  6. Une cause rare de compression médullaire: kyste arachnoïdien épidural rachidien (à propos de 03 cas)

    PubMed Central

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

    2017-01-01

    Le kyste arachnoïdien épidural rachidien (KAER) est une affection bénigne, de physiopathologie encore incertaine. Il est le plus souvent asymptomatique mais peut causer des séquelles neurologiques graves surtout quand le traitement n'est pas instauré à temps. Nous rapportons l'expérience du service de Neurochirurgie CHU Hassan II- Fès concernant la prise en charge du KAER à travers l'analyse rétrospective de trois cas. Il s'agit de deux patients de sexe masculin et d'une femme, d'âge moyen de 35 ans (Extrêmes: 16 et 56 ans), tous admis pour un tableau de compression médullaire lente. Tous nos patients ont bénéficié d'une IRM médullaire qui a mis en évidence une collection liquidienne de siège épidural, ayant le même signal que le LCR, comprimant la moelle en regard. Le siège de la collection était thoracique dans tous les cas. Tous nos patients ont été opérés par voie postérieure avec exérèse du kyste et ligature du collet dans deux cas et une plastie durale dans un seul cas. L'étude anatomopathologique a conclu en un kyste arachnoïdien. L'évolution postopératoire était favorable dans tous les cas. Ce travail a comme objectif de mettre le point sur cette pathologie tout en insistant sur la nécessité d'une prise en charge précoce, vu la tendance vers l'aggravation progressive en l'absence de thérapie adaptée et rappeler les particularités cliniques, paracliniques et thérapeutiques de cette affection. PMID:28533855

  7. Nécrolyse épidermique liée à l'application cutanée d'une solution d'hydroxyde de potassium

    PubMed Central

    Korsaga-Somé, Nina; Tapsoba, Patrice; Ouédraogo, Muriel Sidnoma; Ilboudo, Léopold Baowendsom; Barro-Traoré, Fatou; Niamba, Pascal; Traoré, Adama

    2015-01-01

    Dans nos régions, une solution d'hydroxyde de potassium est régulièrement utilisée en application sur la peau comme traitement traditionnel dans le but de traiter un prurit ou une éruption cutanée. Dans notre pratique quotidienne, nous observons de plus en plus de réactions cutanées à ce type de traitement. Nous rapportons un cas de nécrolyse épidermique généralisée suite à l'application d'une solution concentrée d'hydroxyde de potassium. Il s'agissait d'une patiente de 51 ans, séropositive au VIH2, et au virus de l'hépatite virale C, mais non éligible au traitement antirétroviral. Elle était hospitalisée pour des décollements épidermiques nécrolytiques quasi-généralisés survenue le lendemain de l'application une solution de concentré de potasse sur tout le tégument. Cette solution avait été appliquée dans le but de traiter une éruption micropapuleuse prurigineuse généralisée (exanthème maculo-papuleux) survenue suite à a prise de cotrimoxazole. La réépidermisation était totale sans séquelle après un mois de suivi. Le diagnostic nécrolyse épidermique toxique ou syndrome de Lyell qui met souvent en jeu le pronostic vital avait été écarté devant la conservation de l'état général, l'absence d'atteinte muqueuse et la rapide cicatrisation. Certains traitements traditionnels ont fait la preuve au cours du temps de leur efficacité, mais un mésusage peut être à l'origine d'effets secondaires graves. PMID:26587148

  8. Modélisation des charges d'espace dans les isolants solides par une analyse spectrale

    NASA Astrophysics Data System (ADS)

    Haas, V.; Scouarnec, Ch.; Franceschi, J. L.

    1998-01-01

    A mathematical method based on spectral algebra is developped for the thermal modulation method. These methods permit to measure the space charge distribution in solid insulators. The modelling presented permits to evaluate the performances and the limitations of the measurement method. Une linéarisation par l'algèbre spectrale a été développée dans une méthode de modulation thermique pour mesurer la distribution des charges électriques dans les isolants solides. La modélisation présentée permet d'évaluer les performances et les limites tant numériques que physiques de la méthode de mesure.

  9. Methodologie de modelisation aerostructurelle d'une aile utilisant un logiciel de calcul aerodynamique et un logiciel de calcul par elements finis =

    NASA Astrophysics Data System (ADS)

    Communier, David

    Lors de l'etude structurelle d'une aile d'avion, il est difficile de modeliser fidelement les forces aerodynamiques subies par l'aile de l'avion. Pour faciliter l'analyse, on repartit la portance maximale theorique de l'aile sur son longeron principal ou sur ses nervures. La repartition utilisee implique que l'aile entiere sera plus resistante que necessaire et donc que la structure ne sera pas totalement optimisee. Pour pallier ce probleme, il faudrait s'assurer d'appliquer une repartition aerodynamique de la portance sur la surface complete de l'aile. On serait donc en mesure d'obtenir une repartition des charges sur l'aile beaucoup plus fiable. Pour le realiser, nous aurons besoin de coupler les resultats d'un logiciel calculant les charges aerodynamiques de l'aile avec les resultats d'un logiciel permettant sa conception et son analyse structurelle. Dans ce projet, le logiciel utilise pour calculer les coefficients de pression sur l'aile est XFLR5 et le logiciel permettant la conception et l'analyse structurelle sera CATIA V5. Le logiciel XFLR5 permet une analyse rapide d'une aile en se basant sur l'analyse de ses profils. Ce logiciel calcule les performances des profils de la meme maniere que XFOIL et permet de choisir parmi trois methodes de calcul pour obtenir les performances de l'aile : Lifting Line Theory (LLT), Vortex Lattice Method (VLM) et 3D Panels. Dans notre methodologie, nous utilisons la methode de calcul 3D Panels dont la validite a ete testee en soufflerie pour confirmer les calculs sur XFLR5. En ce qui concerne la conception et l'analyse par des elements finis de la structure, le logiciel CATIA V5 est couramment utilise dans le domaine aerospatial. CATIA V5 permet une automatisation des etapes de conception de l'aile. Ainsi, dans ce memoire, nous allons decrire la methodologie permettant l'etude aerostructurelle d'une aile d'avion.

  10. Etude microdosimetrique de l'influence des materiaux sur l'efficacite biologique d'une source d'iode-125

    NASA Astrophysics Data System (ADS)

    Taschereau, Richard

    Cette these concerne les implants permanents pour la prostate. Les isotopes employes, le 103Pd et l'125I, semblent produire les memes resultats cliniques: le premier a cause d'une radiation plus efficace et le second a cause de sa demi-vie plus longue. La recherche utilise le cadre theorique de la microdosimetrie et des simulations Monte Carlo. Elle propose d'employer le spectre d'ejection dans le calcul de l'efficacite; ce changement fait passer l'efficacite relative du 103Pd de 10% a 5%. Elle montre ensuite qu'il est possible d'ameliorer l'efficacite de la radiation de 125I par l'exploitation des rayons X caracteristiques de la capsule. Une source amelioree faite de molybdene et d'yttrium est donnee en exemple. Elle procure une radiation de 5--7% plus efficace, ce qui surclasse les deux sources existantes. Les applications ne se limitent pas au traitement de la prostate; le traitement du melanome oculaire et la curietherapie endovasculaire pourraient en beneficier.

  11. Etude par Imagerie à faible Niveau dans le proche Infrarouge d'une Emission de la haute Atmosphère

    NASA Astrophysics Data System (ADS)

    Pautet, Pierre-Dominique

    2000-12-01

    Le travail effectué a eu pour but la mise en place d'un protocole d'observation et de traitement des images, ainsi que les outils appropriés, visant à l'étude d'une émission de la haute atmosphère terrestre dans le proche infrarouge. Il existe actuellement des télescopes comme le VLT (Very Large Telescope), installé au Chili, qui permettent d'observer des astres et des galaxies distants de plusieurs millions de parsecs. A cause de l'expansion de l'Univers, des objets situés aussi loin s'éloignent très rapidement de nous. Le spectre de leur émission qui nous parvient alors est décalé vers le rouge ou l'infrarouge, du fait de l'effet Doppler. Il faut donc observer ces objets dans des longueurs d'onde appropriées. Malheureusement, l'atmosphère terrestre qui nous sépare d'eux est aussi le siège de nombreuses émissions qui peuvent venir perturber les mesures. De toutes ces émissions, la principale est due au radical OH dont les raies de rotation-vibration couvrent tout le spectre entre 0,7 et 2,5 microns. Cette émission a lieu au niveau d'une couche assez fine de la haute atmosphère appelée mésopause et située à environ 85 kilomètres d'altitude. Le travail effectué a eu pour but de mettre en évidence les principales caractéristiques de cette émission qui n'est pas uniforme et constante dans le temps. Un programme d'observations dans le proche infrarouge a été élaboré. Plusieurs algorithmes de traitement d'image ont été développés. Un programme d'inversion de perspective a été mis au point pour une utilisation en temps réel sur le terrain. Les caractéristiques des images peuvent être ensuite analysées. La première partie du mémoire comporte une description des différentes émissions lumineuses que l'on peut observer la nuit lorsque l'on regarde la voûte céleste. Ces émissions peuvent avoir deux origines: astronomique ou atmosphérique. Le problème de l'absorption atmosphérique et plus précisément les conditions

  12. L’annonce d’une déficience motrice cérébrale : Une relation de confiance à construire entre les parents, le personnel paramédical et les médecins

    PubMed Central

    Pelchat, Diane; Lefebvre, Hélène; Bouchard, Jean-Marie

    2001-01-01

    RÉSUMÉ : L’annonce d’une déficience motrice cérébrale et des incapacités qui en découlent est une situation difficile à vivre pour les parents et les dispensateurs de soins (personnel paramédical et médecins). Un examen de la documentation médicale démontre que depuis vingt ans, le nombre de parents insatisfaits n’a pas changé. L’étude de type qualitatif et exploratoire, effectuée à la demande de milieux de réadaptation, vise à décrire le processus d’annonce d’un diagnostic de déficience motrice cérébrale (DMC) à partir de l’expérience des différents acteurs en cause et à déterminer les facteurs qui facilitent ou compliquent la relation de confiance. Les résultats indiquent que les parents et les dispensateurs de soins vivent dans deux mondes de perception différents au moment de l’annonce, lesquels se rejoignent difficilement. Les parents sont envahis par le drame qu’ils vivent, tandis que les médecins sont concentrés sur le contenu à transmettre aux parents. Cette annonce provoque une importante incertitude qui bloque la communication entre les partenaires, mais elle pourrait devenir un stimulant à de nouvelles stratégies d’adaptation. PMID:20084263

  13. La pubalgie du sportif: mise au point à propos d'une étude rétrospective de 128 joueurs

    PubMed Central

    Mahmoudi, Ammar; Frioui, Samia; Jemni, Sonia; Khachnaoui, Faycel; Dahmene, Younes

    2015-01-01

    La pubalgie du sportif de haut niveau représente une entité nosologique à part entière, tant en raison du mécanisme à l'origine de la pathologie que des lésions objectivables au niveau de la paroi abdominale. C'est un syndrome douloureux de la région inguino-pubienne qui touche particulièrement les footballeurs. Son étiologie est attribuée à la répétition de mouvements des membres inférieurs et du tronc associant rotation et adduction forcées. Son incidence est nettement plus élevée chez les hommes. Après avoir écarté une pathologie d'organe, le patient devrait bénéficier tout au début de son traitement conservateur d'une IRM afin d'effectuer un bilan lésionnel complet qui, selon les situations, permet d’écourter le traitement conservateur et de proposer un traitement chirurgical optimal. Le traitement doit être résolument conservateur pendant 3 mois. La rééducation est le plus souvent le traitement de première intention. Les patients présentant une persistance des symptômes sont candidats à la chirurgie. L'intervention de Nesovic est le traitement de choix chez les sportifs de haut niveau et qui permet, dans la très grande majorité des cas, une reprise sans aucune limitation de l'activité sportive antérieure. La technique de Bassini semble être moins lourde que celle de Nesovic, puisqu'elle est moins invasive. Une prise en charge multidisciplinaire centrée sur l'athlète avant et après l'intervention permet un retour aux activités physiques après quelques mois. Nous rapportons l'expérience de la prise en charge de 128 joueurs opérés selon la technique de Bassini et nous comparons nos résultats avec celles de la littérature. PMID:26966484

  14. Developpement d'une methode calorimetrique de mesure des pertes ac pour des rubans supraconducteurs a haute temperature critique

    NASA Astrophysics Data System (ADS)

    Dolez, Patricia

    Le travail de recherche effectue dans le cadre de ce projet de doctorat a permis la mise au point d'une methode de mesure des pertes ac destinee a l'etude des supraconducteurs a haute temperature critique. Pour le choix des principes de cette methode, nous nous sommes inspires de travaux anterieurs realises sur les supraconducteurs conventionnels, afin de proposer une alternative a la technique electrique, presentant lors du debut de cette these des problemes lies a la variation du resultat des mesures selon la position des contacts de tension sur la surface de l'echantillon, et de pouvoir mesurer les pertes ac dans des conditions simulant la realite des futures applications industrielles des rubans supraconducteurs: en particulier, cette methode utilise la technique calorimetrique, associee a une calibration simultanee et in situ. La validite de la methode a ete verifiee de maniere theorique et experimentale: d'une part, des mesures ont ete realisees sur des echantillons de Bi-2223 recouverts d'argent ou d'alliage d'argent-or et comparees avec les predictions theoriques donnees par Norris, nous indiquant la nature majoritairement hysteretique des pertes ac dans nos echantillons; d'autre part, une mesure electrique a ete realisee in situ dont les resultats correspondent parfaitement a ceux donnes par notre methode calorimetrique. Par ailleurs, nous avons compare la dependance en courant et en frequence des pertes ac d'un echantillon avant et apres qu'il ait ete endommage. Ces mesures semblent indiquer une relation entre la valeur du coefficient de la loi de puissance modelisant la dependance des pertes avec le courant, et les inhomogeneites longitudinales du courant critique induites par l'endommagement. De plus, la variation en frequence montre qu'au niveau des grosses fractures transverses creees par l'endommagement dans le coeur supraconducteur, le courant se partage localement de maniere a peu pres equivalente entre les quelques grains de matiere

  15. ÉVALUER UNE INTERVENTION COMPLEXE: ENJEUX CONCEPTUELS, MÉTHODOLOGIQUES, ET OPÉRATIONNELS

    PubMed Central

    Contandriopoulos, André-Pierre; Rey, Lynda; Brousselle, Astrid; Champagne, François

    2016-01-01

    L’évaluation doit théoriquement aider les décideurs à relever les défis des systèmes de santé contemporains. Paradoxalement, malgré le développement rapide du domaine, l’utilisation des résultats des évaluations par ces décideurs reste faible. Le degré d’utilisation ne dépendrait-il pas de la capacité de l’évaluateur à rendre compte de la complexité des systèmes de santé? La nature complexe d’une intervention amène souvent les évaluateurs à adopter des approches non conventionnelles tenant compte du jeu des acteurs. L’évaluation d’une intervention complexe soulève des enjeux conceptuels, méthodologiques, et opérationnels que doit surmonter l’évaluateur pour accroître le degré d’utilisation des résultats par les décideurs. PMID:27293310

  16. Hématome sous capsulaire de foie compliquant une pré-éclampsie: à propos de 6 cas

    PubMed Central

    Mamouni, Nisrine; Derkaoui, Ali; Bougern, Hakima; Bouchikhi, Chehrazad; Chaara, Hikmat; Banani, Abdelaziz; Abdelilah, Melhouf Moulay

    2011-01-01

    L'hématome sous capsulaire du foie (HSCF) est une complication rare mais gravissime de la grossesse. Devant une symptomatologie clinique souvent non spécifique et un tableau biologique retardé, son diagnostic est basé essentiellement sur les moyens de l'imagerie (échographie, TDM, IRM). Son traitement est fonction de l'intégrité ou non de la capsule de Glisson. Nous rapportons les observations de 6 patientes, à travers une étude rétrospective s’étalant sur la période du Janvier 2005 à Octobre 2008, incluant tous les cas de preeclampsie colligés au service de gynécologie obstétrique du CHU Hassan II. Durant la période d’étude, L'incidence de l'hématome sous capsulaire de foie chez les patientes préeclamptiques admises durant la période d’étude est de 1,49 %. Aucune des patientes n'a benificié d'un suivi prénatal au sein de notre formation. La moyenne d’âge des patientes est de 37,6 ans avec des extrêmes allant de 33 à 45 ans. La gestité moyenne était de 4,8 avec une parité moyenne de 4,5.l'hematome sous capsulaire est survenu en post partum chez tous nos cas avec un délai moyen de 4 jours et des extrêmes allant de J0 et J10 du post partum .Toutes les patientes ont présenté un HELLP syndrome concomitant à la survenue de cette complication gravissime.Le diagnostic positif s'est basé sur les données échographiques dans 5 cas (hemoperitoine –HSCF).l’équipe a opté pour une abstention thérapeutique avec surveillance armée chez 2 cas et l'exploration chirurgicale a été indiquée chez quatre patientes en instabilité hemodynamique.Nous avons déploré deux cas de décès maternel. PMID:22145072

  17. Earth: Earth Science and Health

    NASA Technical Reports Server (NTRS)

    Maynard, Nancy G.

    2001-01-01

    A major new NASA initiative on environmental change and health has been established to promote the application of Earth science remote sensing data, information, observations, and technologies to issues of human health. NASA's Earth Sciences suite of Earth observing instruments are now providing improved observations science, data, and advanced technologies about the Earth's land, atmosphere, and oceans. These new space-based resources are being combined with other agency and university resources, data integration and fusion technologies, geographic information systems (GIS), and the spectrum of tools available from the public health community, making it possible to better understand how the environment and climate are linked to specific diseases, to improve outbreak prediction, and to minimize disease risk. This presentation is an overview of NASA's tools, capabilities, and research advances in this initiative.

  18. La syphilis congénitale révélée par une fracture spontanée

    PubMed Central

    Idrissi, Mounia Lakhdar; Ismaili, Leila; Bouharrou, Abdelhak; Hida, Moustapha

    2011-01-01

    Alors qu'elle est actuellement oubliée dans les pays développés, la syphilis congénitale se voit encore chez nous faute du dépistage anténatal. Ses formes cliniques sont polymorphes et orientent à tord vers d'autres pathologies surtout en période néonatale. Le diagnostic n'est donc pas toujours facile. La révélation d'une syphilis congénitale par une fracture spontanée est exceptionnellement décrite. Nous rapportons dans ce travail le cas d'un nourrisson de 2 mois ramené en consultation pour limitation douloureuse des mouvements du bras droit. Le diagnostic est évoqué sur les données radiologiques et confirmé par la sérologie syphilitique. Le traitement a reposé essentiellement sur l'administration de la pénicilline G avec une bonne évolution clinique. PMID:22384288

  19. Lambeau Expanse du Cuir Chevelu dans la Couverture des Alopecies Cicatricielles sur Sequelles de Brulures. A Propos d'une Observation

    PubMed Central

    El Mazouz, S.; Hafidi, J.; Fejjal, N.; Mejjati, H.; Cherkab, L.; Gharib, N.; Abbassi, A.

    2010-01-01

    Summary Les séquelles esthétiques des alopécies cicatricielles sur séquelles de brûlures sont responsables de préjudices empêchant parfois la réinsertion sociale du patient, surtout chez les sujets de sexe féminin. Le cuir chevelu permet la réalisation de lambeaux permettant de couvrir ces alopécies. Les Auteurs décrivent le cas d'une jeune patiente victime d'une alopécie cicatricielle sur séquelles de brûlures chez qui ils ont réalisé un lambeau expansé du cuir chevelu et mettent le point sur la prise en charge de ces lésions à travers ce cas clinique et une revue de littérature. PMID:21991195

  20. An Earth-sized planet with an Earth-like density.

    PubMed

    Pepe, Francesco; Cameron, Andrew Collier; Latham, David W; Molinari, Emilio; Udry, Stéphane; Bonomo, Aldo S; Buchhave, Lars A; Charbonneau, David; Cosentino, Rosario; Dressing, Courtney D; Dumusque, Xavier; Figueira, Pedro; Fiorenzano, Aldo F M; Gettel, Sara; Harutyunyan, Avet; Haywood, Raphaëlle D; Horne, Keith; Lopez-Morales, Mercedes; Lovis, Christophe; Malavolta, Luca; Mayor, Michel; Micela, Giusi; Motalebi, Fatemeh; Nascimbeni, Valerio; Phillips, David; Piotto, Giampaolo; Pollacco, Don; Queloz, Didier; Rice, Ken; Sasselov, Dimitar; Ségransan, Damien; Sozzetti, Alessandro; Szentgyorgyi, Andrew; Watson, Christopher A

    2013-11-21

    Recent analyses of data from the NASA Kepler spacecraft have established that planets with radii within 25 per cent of the Earth's (R Earth symbol) are commonplace throughout the Galaxy, orbiting at least 16.5 per cent of Sun-like stars. Because these studies were sensitive to the sizes of the planets but not their masses, the question remains whether these Earth-sized planets are indeed similar to the Earth in bulk composition. The smallest planets for which masses have been accurately determined are Kepler-10b (1.42 R Earth symbol) and Kepler-36b (1.49 R Earth symbol), which are both significantly larger than the Earth. Recently, the planet Kepler-78b was discovered and found to have a radius of only 1.16 R Earth symbol. Here we report that the mass of this planet is 1.86 Earth masses. The resulting mean density of the planet is 5.57 g cm(-3), which is similar to that of the Earth and implies a composition of iron and rock.

  1. Discover Earth

    NASA Technical Reports Server (NTRS)

    Steele, Colleen

    1998-01-01

    Discover Earth is a NASA-sponsored project for teachers of grades 5-12, designed to: (1) enhance understanding of the Earth as an integrated system; (2) enhance the interdisciplinary approach to science instruction; and (3) provide classroom materials that focus on those goals. Discover Earth is conducted by the Institute for Global Environmental Strategies in collaboration with Dr. Eric Barron, Director, Earth System Science Center, The Pennsylvania State University; and Dr. Robert Hudson, Chair, the Department of Meteorology, University of Maryland at College Park. The enclosed materials: (1) represent only part of the Discover Earth materials; (2) were developed by classroom teachers who are participating in the Discover Earth project; (3) utilize an investigative approach and on-line data; and (4) can be effectively adjusted to classrooms with greater/without technology access. The Discover Earth classroom materials focus on the Earth system and key issues of global climate change including topics such as the greenhouse effect, clouds and Earth's radiation balance, surface hydrology and land cover, and volcanoes and climate change. All the materials developed to date are available on line at (http://www.strategies.org) You are encouraged to submit comments and recommendations about these materials to the Discover Earth project manager, contact information is listed below. You are welcome to duplicate all these materials.

  2. The measurement of Earth rotation on a deformable Earth

    NASA Technical Reports Server (NTRS)

    Cannon, W. H.

    1980-01-01

    Until recently, the methods of geodetic positioning on the Earth were limited to a precision of roughly one part in 10 to the 6th power. At this level of precision, the Earth can be regarded as a rigid body since the largest departure of the Earth from rigidity is manifested in the strains of the Earth tides which are of the order of one part in 10 to the 7th power. Long baseline interferometry is expected to routinely provide global positioning to a precision of one part in 10 to the 8th power or better. At this level of precision, all parts of the Earth's surface must be regarded as being, at least potentially, in continual motion relative to the geocenter as a result of a variety of geophysical effects. The general implications of this phenomenon for the theory of the Earth's rotation is discussed. Particular attention is given to the question of the measurement of the 'Earth's rotation vector' on a deformable Earth.

  3. Choriorétinite extensive bilatérale révélant une infection par le virus de l'immunodéficience humaine (VIH)

    PubMed Central

    El Yamouni, Oubaida; Tzili, Nazih; El Hassan, Abdallah; Slassi, Nadia; El Khaoua, Mahfoud; Jebbar, Zakaria; Berraho, Amina

    2014-01-01

    Au cours de l'infection par le virus de l'immunodéficience humaine(VIH), Les atteintes oculaires sont polymorphes, pouvant compromettre le pronostic fonctionnel. Nous rapportons l'observation d'un patient présentant une choriorétinite infectieuse sévère révélant une infection par le VIH. Patient âgé de 35 ans avec antécédent de tuberculose pulmonaire en 2007, consulte pour BAV bilatérale progressive depuis 6 mois. Une acuité visuelle à compte les doigts au niveau de l'oeil droit et à mouvement des doigts au niveau de l'oeil gauche, avec présence de foyers choriorétiniens diffus visualisés au fond d'oeil et à l'angiographie. Les sérologies VIH, toxoplasmose et CMV sont positives. Le patient a été mis sous traitement anti-toxoplasmose (Sulfadiazine et pyriméthamine) et anti-CMV (Ganciclovir per os). L’évolution sous traitement a été marquée par une régression de la hyalite avec la persistance des foyers choriorétiniens évolutifs et une acuité visuelle réduite à perception lumineuse. PMID:25709723

  4. Le stress perçu: validation de la traduction d'une échelle de mesure de stress en dialecte marocain

    PubMed Central

    Loubir, Dalal Ben; Serhier, Zeineb; Otmani, Nada; Housbane, Samy; Mouddene, Naima Ait; Agoub, Mohamed; Othmani, Mohammed Bennani

    2015-01-01

    Introduction L'article a pour objectif de valider la traduction en dialecte arabe Marocain, de l’échelle du stress perçu « Perceived Stress Scale » chez un large échantillon de la population marocaine. Méthodes Une méthode de traduction et contre traduction en dialecte Marocain a été réalisée pour l’échelle « Perceived Stress Scale » à 10 items. Une étude de type transversale, a été menée par la suite en suivant un échantillonnage par quotas qui a ciblé les individus âgés de plus de 18 ans et appartenant à différentes catégories sociales. Les participants ont répondus aux versions marocaines de l’échelle « Perceived Stress Scale » et d'une version réduite de l’échelle « The Survey of Recent Life Experience ». La validation des qualités métrologiques a été établie en examinant: la fiabilité interne, la fiabilité test-retest, la validité convergente et la structure factorielle. Résultats Cinq cent trente-cinq participants ont répondu aux questionnaires. La version marocaine de l’échelle « Perceived Stress Scale » a présenté une bonne fiabilité interne (α = 0,80) et fiabilité test-retest (CCI= 0,87). D'autant plus, l'analyse en composante principale de l’échelle « Perceived Stress Scale » a permis d'extraire deux facteurs qui ont permis d'expliquer 53,4% de la variance totale. Les deux échelles utilisées étaient assez bien corrélées (r = 0,467, p < 0,01). Conclusion La présente étude a permis d'obtenir une version marocaine de l’échelle « Perceived Stress Scale » avec des propriétés psychométriques satisfaisantes, dont l'utilisation sera d'une grande aide dans la pratique médicale, aussi bien que dans la réalisation des études de recherche qui s'intéressent au stress psychologique. PMID:26587130

  5. Ulcérations buccales et péri-anales: un mode de révélation inhabituel d'une granulomatose avec polyangéite - à propos d'un cas

    PubMed Central

    Jaafoura, Neirouz Ghannouchi; Thaljaoui, Wathek; Atig, Amira; Bouker, Ahmed; Khalifa, Mabrouk; Bahri, Fathi

    2014-01-01

    La granulomatose avec polyangéite, est une vascularite systémique rare qui touche avec prédilection les voies aériennes supérieures, les poumons et les reins. L'atteinte cutanéo-muqueuse ainsi que l'atteinte digestive ne sont pas inhabituelles mais elles sont rarement inaugurales de la maladie. Nous rapportons l'observation d'une femme âgée de 57 ans, ayant une granulomatose avec polyangéite multi-systémique avec comme premières manifestations une atteinte cutanéo-muqueuse à type de nécrose de la langue et d'ulcérations péri-anales ainsi que des rectorragies. La présence de signes radiologiques orientant vers une hémmorragie intra-alvéolaire, l'atteinte rénale, l'atteinte neurologique périphérique ainsi que la positivité des C-ANCA de type anti-PR3 ont permis de rattacher les manifestations dermatologiques à cette vascularite. Des manifestations cutanéo-muqueuses atypiques, au cours d'une granulomateuse avec polyangéite, doivent être connues par le clinicien pour un diagnostic et une prise en charge adéquate. PMID:25404981

  6. Le dermatofibrosarcome de Darier et Ferrand, une tumeur cutanée particulière: à propos de 32 cas et revue de la littérature

    PubMed Central

    Elamrani, Driss; Droussi, Hatim; Boukind, Samira; Elatiqi, Keltoum; Dlimi, Meriem; Benchamkha, Yassine; Ettalbi, Saloua

    2014-01-01

    Le dermatofibrosarcome (DFS) est une tumeur fibreuse de la peau, de croissance lente, à très haut risque de récidive locale, mais à potentiel métastatique faible. A partir d'une étude rétrospective étalée sur une période de 5 ans (décembre 2008 - décembre 2013), nous avons analysé les caractéristiques épidémiologiques et cliniques, le délai de diagnostic, le type de thérapeutique et le devenir de 32 patients présentant des tumeurs de Darier et Ferrand histologiquement prouvées. Parmi les 32 patients, 10 se sont présentés initialement au service pour une récidive tumorale. Une discrète prédominance masculine a été notée. Les DFS touchent préférentiellement l'adulte jeune. Le délai diagnostique observé est en moyenne de 4 ans. Le tronc est la localisation préférentielle (60%), suivi par les extrémités proximales (30%). Les 32 patients ont été traités par exérèse chirurgicale avec une marge de 5cm en surface, emportant en profondeur une barrière anatomique saine. La couverture de la perte de substance (PDS) a été réalisée après confirmation anatomopathologique du caractère carcinologique de l'exérèse, et a fait appel à différents moyens allant de la greffe cutanée aux lambeaux musculo –cutanés libres. L’évolution a été marquée par la survenue d'une récidive tumorale chez 8 patients (3 cas parmi les tumeurs vues en première intention et 5 cas parmi les tumeurs vues en récidive) et les résultats ont été jugés satisfaisants sur le plan esthétique et fonctionnel. Le DFS de Darier et Ferrand est une tumeur dont le pronostic et le risque évolutif sont principalement liés au délai diagnostic et la qualité de la première exérèse. Le diagnostic tardif, rend difficile la chirurgie d'exérèse et de reconstruction Les possibilités de guérison en cas de chirurgie primaire bien conduite sont significativement supérieures à celles d'une chirurgie de rattrapage. L'amélioration du pronostic passe par

  7. Earth as an Extrasolar Planet: Earth Model Validation Using EPOXI Earth Observations

    NASA Technical Reports Server (NTRS)

    Robinson, Tyler D.; Meadows, Victoria S.; Crisp, David; Deming, Drake; A'Hearn, Michael F.; Charbonneau, David; Livengood, Timothy A.; Seager, Sara; Barry, Richard; Hearty, Thomas; hide

    2011-01-01

    The EPOXI Discovery Mission of Opportunity reused the Deep Impact flyby spacecraft to obtain spatially and temporally resolved visible photometric and moderate resolution near-infrared (NIR) spectroscopic observations of Earth. These remote observations provide a rigorous validation of whole disk Earth model simulations used to better under- stand remotely detectable extrasolar planet characteristics. We have used these data to upgrade, correct, and validate the NASA Astrobiology Institute s Virtual Planetary Laboratory three-dimensional line-by-line, multiple-scattering spectral Earth model (Tinetti et al., 2006a,b). This comprehensive model now includes specular reflectance from the ocean and explicitly includes atmospheric effects such as Rayleigh scattering, gas absorption, and temperature structure. We have used this model to generate spatially and temporally resolved synthetic spectra and images of Earth for the dates of EPOXI observation. Model parameters were varied to yield an optimum fit to the data. We found that a minimum spatial resolution of approx.100 pixels on the visible disk, and four categories of water clouds, which were defined using observed cloud positions and optical thicknesses, were needed to yield acceptable fits. The validated model provides a simultaneous fit to the Earth s lightcurve, absolute brightness, and spectral data, with a root-mean-square error of typically less than 3% for the multiwavelength lightcurves, and residuals of approx.10% for the absolute brightness throughout the visible and NIR spectral range. We extend our validation into the mid-infrared by comparing the model to high spectral resolution observations of Earth from the Atmospheric Infrared Sounder, obtaining a fit with residuals of approx.7%, and temperature errors of less than 1K in the atmospheric window. For the purpose of understanding the observable characteristics of the distant Earth at arbitrary viewing geometry and observing cadence, our validated

  8. Earth as an Extrasolar Planet: Earth Model Validation Using EPOXI Earth Observations

    NASA Astrophysics Data System (ADS)

    Robinson, Tyler D.; Meadows, Victoria S.; Crisp, David; Deming, Drake; A'Hearn, Michael F.; Charbonneau, David; Livengood, Timothy A.; Seager, Sara; Barry, Richard K.; Hearty, Thomas; Hewagama, Tilak; Lisse, Carey M.; McFadden, Lucy A.; Wellnitz, Dennis D.

    2011-06-01

    The EPOXI Discovery Mission of Opportunity reused the Deep Impact flyby spacecraft to obtain spatially and temporally resolved visible photometric and moderate resolution near-infrared (NIR) spectroscopic observations of Earth. These remote observations provide a rigorous validation of whole-disk Earth model simulations used to better understand remotely detectable extrasolar planet characteristics. We have used these data to upgrade, correct, and validate the NASA Astrobiology Institute's Virtual Planetary Laboratory three-dimensional line-by-line, multiple-scattering spectral Earth model. This comprehensive model now includes specular reflectance from the ocean and explicitly includes atmospheric effects such as Rayleigh scattering, gas absorption, and temperature structure. We have used this model to generate spatially and temporally resolved synthetic spectra and images of Earth for the dates of EPOXI observation. Model parameters were varied to yield an optimum fit to the data. We found that a minimum spatial resolution of ∼100 pixels on the visible disk, and four categories of water clouds, which were defined by using observed cloud positions and optical thicknesses, were needed to yield acceptable fits. The validated model provides a simultaneous fit to Earth's lightcurve, absolute brightness, and spectral data, with a root-mean-square (RMS) error of typically less than 3% for the multiwavelength lightcurves and residuals of ∼10% for the absolute brightness throughout the visible and NIR spectral range. We have extended our validation into the mid-infrared by comparing the model to high spectral resolution observations of Earth from the Atmospheric Infrared Sounder, obtaining a fit with residuals of ∼7% and brightness temperature errors of less than 1 K in the atmospheric window. For the purpose of understanding the observable characteristics of the distant Earth at arbitrary viewing geometry and observing cadence, our validated forward model can be

  9. Earth as an extrasolar planet: Earth model validation using EPOXI earth observations.

    PubMed

    Robinson, Tyler D; Meadows, Victoria S; Crisp, David; Deming, Drake; A'hearn, Michael F; Charbonneau, David; Livengood, Timothy A; Seager, Sara; Barry, Richard K; Hearty, Thomas; Hewagama, Tilak; Lisse, Carey M; McFadden, Lucy A; Wellnitz, Dennis D

    2011-06-01

    The EPOXI Discovery Mission of Opportunity reused the Deep Impact flyby spacecraft to obtain spatially and temporally resolved visible photometric and moderate resolution near-infrared (NIR) spectroscopic observations of Earth. These remote observations provide a rigorous validation of whole-disk Earth model simulations used to better understand remotely detectable extrasolar planet characteristics. We have used these data to upgrade, correct, and validate the NASA Astrobiology Institute's Virtual Planetary Laboratory three-dimensional line-by-line, multiple-scattering spectral Earth model. This comprehensive model now includes specular reflectance from the ocean and explicitly includes atmospheric effects such as Rayleigh scattering, gas absorption, and temperature structure. We have used this model to generate spatially and temporally resolved synthetic spectra and images of Earth for the dates of EPOXI observation. Model parameters were varied to yield an optimum fit to the data. We found that a minimum spatial resolution of ∼100 pixels on the visible disk, and four categories of water clouds, which were defined by using observed cloud positions and optical thicknesses, were needed to yield acceptable fits. The validated model provides a simultaneous fit to Earth's lightcurve, absolute brightness, and spectral data, with a root-mean-square (RMS) error of typically less than 3% for the multiwavelength lightcurves and residuals of ∼10% for the absolute brightness throughout the visible and NIR spectral range. We have extended our validation into the mid-infrared by comparing the model to high spectral resolution observations of Earth from the Atmospheric Infrared Sounder, obtaining a fit with residuals of ∼7% and brightness temperature errors of less than 1 K in the atmospheric window. For the purpose of understanding the observable characteristics of the distant Earth at arbitrary viewing geometry and observing cadence, our validated forward model can be

  10. Earth as an Extrasolar Planet: Earth Model Validation Using EPOXI Earth Observations

    PubMed Central

    Meadows, Victoria S.; Crisp, David; Deming, Drake; A'Hearn, Michael F.; Charbonneau, David; Livengood, Timothy A.; Seager, Sara; Barry, Richard K.; Hearty, Thomas; Hewagama, Tilak; Lisse, Carey M.; McFadden, Lucy A.; Wellnitz, Dennis D.

    2011-01-01

    Abstract The EPOXI Discovery Mission of Opportunity reused the Deep Impact flyby spacecraft to obtain spatially and temporally resolved visible photometric and moderate resolution near-infrared (NIR) spectroscopic observations of Earth. These remote observations provide a rigorous validation of whole-disk Earth model simulations used to better understand remotely detectable extrasolar planet characteristics. We have used these data to upgrade, correct, and validate the NASA Astrobiology Institute's Virtual Planetary Laboratory three-dimensional line-by-line, multiple-scattering spectral Earth model. This comprehensive model now includes specular reflectance from the ocean and explicitly includes atmospheric effects such as Rayleigh scattering, gas absorption, and temperature structure. We have used this model to generate spatially and temporally resolved synthetic spectra and images of Earth for the dates of EPOXI observation. Model parameters were varied to yield an optimum fit to the data. We found that a minimum spatial resolution of ∼100 pixels on the visible disk, and four categories of water clouds, which were defined by using observed cloud positions and optical thicknesses, were needed to yield acceptable fits. The validated model provides a simultaneous fit to Earth's lightcurve, absolute brightness, and spectral data, with a root-mean-square (RMS) error of typically less than 3% for the multiwavelength lightcurves and residuals of ∼10% for the absolute brightness throughout the visible and NIR spectral range. We have extended our validation into the mid-infrared by comparing the model to high spectral resolution observations of Earth from the Atmospheric Infrared Sounder, obtaining a fit with residuals of ∼7% and brightness temperature errors of less than 1 K in the atmospheric window. For the purpose of understanding the observable characteristics of the distant Earth at arbitrary viewing geometry and observing cadence, our validated forward

  11. Earth From Space: "Beautiful Earth's" Integration of Media Arts, Earth Science, and Native Wisdom in Informal Learning Environments

    NASA Astrophysics Data System (ADS)

    Casasanto, V.; Hallowell, R.; Williams, K.; Rock, J.; Markus, T.

    2015-12-01

    "Beautiful Earth: Experiencing and Learning Science in an Engaging Way" was a 3-year project funded by NASA's Competitive Opportunities in Education and Public Outreach for Earth and Space Science. An outgrowth of Kenji Williams' BELLA GAIA performance, Beautiful Earth fostered a new approach to teaching by combining live music, data visualizations and Earth science with indigenous perspectives, and hands-on workshops for K-12 students at 5 science centers. Inspired by the "Overview Effect," described by many astronauts who were awestruck by seeing the Earth from space and their realization of the profound interconnectedness of Earth's life systems, Beautiful Earth leveraged the power of multimedia performance to serve as a springboard to engage K-12 students in hands-on Earth science and Native wisdom workshops. Results will be presented regarding student perceptions of Earth science, environmental issues, and indigenous ways of knowing from 3 years of evaluation data.

  12. Digital Earth - A sustainable Earth

    NASA Astrophysics Data System (ADS)

    Mahavir

    2014-02-01

    All life, particularly human, cannot be sustainable, unless complimented with shelter, poverty reduction, provision of basic infrastructure and services, equal opportunities and social justice. Yet, in the context of cities, it is believed that they can accommodate more and more people, endlessly, regardless to their carrying capacity and increasing ecological footprint. The 'inclusion', for bringing more and more people in the purview of development is often limited to social and economic inclusion rather than spatial and ecological inclusion. Economic investment decisions are also not always supported with spatial planning decisions. Most planning for a sustainable Earth, be at a level of rural settlement, city, region, national or Global, fail on the capacity and capability fronts. In India, for example, out of some 8,000 towns and cities, Master Plans exist for only about 1,800. A chapter on sustainability or environment is neither statutorily compulsory nor a norm for these Master Plans. Geospatial technologies including Remote Sensing, GIS, Indian National Spatial Data Infrastructure (NSDI), Indian National Urban Information Systems (NUIS), Indian Environmental Information System (ENVIS), and Indian National GIS (NGIS), etc. have potential to map, analyse, visualize and take sustainable developmental decisions based on participatory social, economic and social inclusion. Sustainable Earth, at all scales, is a logical and natural outcome of a digitally mapped, conceived and planned Earth. Digital Earth, in fact, itself offers a platform to dovetail the ecological, social and economic considerations in transforming it into a sustainable Earth.

  13. Low-energy near Earth asteroid capture using Earth flybys and aerobraking

    NASA Astrophysics Data System (ADS)

    Tan, Minghu; McInnes, Colin; Ceriotti, Matteo

    2018-04-01

    Since the Sun-Earth libration points L1 and L2 are regarded as ideal locations for space science missions and candidate gateways for future crewed interplanetary missions, capturing near-Earth asteroids (NEAs) around the Sun-Earth L1/L2 points has generated significant interest. Therefore, this paper proposes the concept of coupling together a flyby of the Earth and then capturing small NEAs onto Sun-Earth L1/L2 periodic orbits. In this capture strategy, the Sun-Earth circular restricted three-body problem (CRTBP) is used to calculate target Lypaunov orbits and their invariant manifolds. A periapsis map is then employed to determine the required perigee of the Earth flyby. Moreover, depending on the perigee distance of the flyby, Earth flybys with and without aerobraking are investigated to design a transfer trajectory capturing a small NEA from its initial orbit to the stable manifolds associated with Sun-Earth L1/L2 periodic orbits. Finally, a global optimization is carried out, based on a detailed design procedure for NEA capture using an Earth flyby. Results show that the NEA capture strategies using an Earth flyby with and without aerobraking both have the potential to be of lower cost in terms of energy requirements than a direct NEA capture strategy without the Earth flyby. Moreover, NEA capture with an Earth flyby also has the potential for a shorter flight time compared to the NEA capture strategy without the Earth flyby.

  14. Ancient Earth, Alien Earths Event

    NASA Image and Video Library

    2014-08-20

    Panelists pose for a group photo at the “Ancient Earth, Alien Earths” Event at NASA Headquarters in Washington, DC Wednesday, August 20, 2014. The event was sponsored by NASA, the National Science Foundation (NSF), and the Smithsonian Institution and highlighted how research on early Earth could help guide our search for habitable planets orbiting other stars. Photo Credit: (NASA/Aubrey Gemignani)

  15. Fabrication de memoire monoelectronique non volatile par une approche de nanogrille flottante

    NASA Astrophysics Data System (ADS)

    Guilmain, Marc

    Les transistors monoelectroniques (SET) sont des dispositifs de tailles nanometriques qui permettent la commande d'un electron a la fois et donc, qui consomment peu d'energie. Une des applications complementaires des SET qui attire l'attention est son utilisation dans des circuits de memoire. Une memoire monoelectronique (SEM) non volatile a le potentiel d'operer a des frequences de l'ordre des gigahertz ce qui lui permettrait de remplacer en meme temps les memoires mortes de type FLASH et les memoires vives de type DRAM. Une puce SEM permettrait donc ultimement la reunification des deux grands types de memoire au sein des ordinateurs. Cette these porte sur la fabrication de memoires monoelectroniques non volatiles. Le procede de fabrication propose repose sur le procede nanodamascene developpe par C. Dubuc et al. a 1'Universite de Sherbrooke. L'un des avantages de ce procede est sa compatibilite avec le back-end-of-line (BEOL) des circuits CMOS. Ce procede a le potentiel de fabriquer plusieurs couches de circuits memoirestres denses au-dessus de tranches CMOS. Ce document presente, entre autres, la realisation d'un simulateur de memoires monoelectroniques ainsi que les resultats de simulations de differentes structures. L'optimisation du procede de fabrication de dispositifs monoelectroniques et la realisation de differentes architectures de SEM simples sont traitees. Les optimisations ont ete faites a plusieurs niveaux : l'electrolithographie, la gravure de l'oxyde, le soulevement du titane, la metallisation et la planarisation CMP. La caracterisation electrique a permis d'etudier en profondeur les dispositifs formes de jonction de Ti/TiO2 et elle a demontre que ces materiaux ne sont pas appropries. Par contre, un SET forme de jonction de TiN/Al2O3 a ete fabrique et caracterise avec succes a basse temperature. Cette demonstration demontre le potentiel du procede de fabrication et de la deposition de couche atomique (ALD) pour la fabrication de memoires

  16. Variation spatiotemporelle de la cryptorchidie et de l’hypospadias au Québec : Une étude exploratoire

    PubMed Central

    Guertin, Sophie; Lemieux, Karine-Sylvie; Makhoulian, Natalie; Michaud, Sébastien; Patry, Rose-Marie; Côté, Anne-Andrée; Gagnon, Fabien; Ayotte, Pierre; Bolduc, Stéphane

    2011-01-01

    Résumé Objectifs : La majorité des études effectuées au cours des dernières décennies ont mis en évidence une augmentation du nombre de cas de cryptorchidie et d’hypospadias entre 1970 et 1990. De plus, l’importante variabilité géographique de ces anomalies est bien décrite. Cette étude vise à mesurer la prévalence à la naissance de la cryptorchidie et de l’hypospadias au Québec, à vérifier si ces anomalies sont en augmentation et à en évaluer la répartition interrégionale. Méthode : Une étude épidémiologique descriptive a été réalisée à partir du nombre de garçons de cinq ans et moins hospitalisés pour une cryptorchidie ou un hypospadias au Québec de 1989 à 2004 selon les données du fichier administratif d’hospitalisation MED-ÉCHO. Les données sur les naissances provenaient de l’Institut de la statistique du Québec. Résultats : La prévalence annuelle moyenne pour 1000 naissances vivantes de sexe masculin est de 19,1 (IC à 95 % : 18,8–19,4) pour la cryptorchidie et 11,4 (IC à 95 % 11,1–11,6) pour l’hypospadias au Québec. Au cours de la période étudiée, la prévalence de cryptorchidie a légèrement diminué, alors que celle de l’hypospadias est demeurée stable. Comparativement à la province du Québec, des régions présentent une prévalence significativement différente de cryptorchidie et/ou d’hypospadias. . Conclusion : Au Québec, la prévalence de cryptorchidie est en légère diminution alors que celle de l’hypospadias est stable. Des variations régionales significatives sont observables. D’autres études sont nécessaires afin d’évaluer l’hypothèse d’un lien avec les contaminants environnementaux en émergence. L’implantation d’un système de surveillance des anomalies congénitales permettrait une représentation plus valide de la situation. PMID:21672476

  17. Variation spatiotemporelle de la cryptorchidie et de l'hypospadias au Québec : Une étude exploratoire.

    PubMed

    Guertin, Sophie; Lemieux, Karine-Sylvie; Makhoulian, Natalie; Michaud, Sébastien; Patry, Rose-Marie; Côté, Anne-Andrée; Gagnon, Fabien; Ayotte, Pierre; Bolduc, Stéphane

    2011-06-01

    RéSUMé: : La majorité des études effectuées au cours des dernières décennies ont mis en évidence une augmentation du nombre de cas de cryptorchidie et d'hypospadias entre 1970 et 1990. De plus, l'importante variabilité géographique de ces anomalies est bien décrite. Cette étude vise à mesurer la prévalence à la naissance de la cryptorchidie et de l'hypospadias au Québec, à vérifier si ces anomalies sont en augmentation et à en évaluer la répartition interrégionale. MéTHODE :: Une étude épidémiologique descriptive a été réalisée à partir du nombre de garçons de cinq ans et moins hospitalisés pour une cryptorchidie ou un hypospadias au Québec de 1989 à 2004 selon les données du fichier administratif d'hospitalisation MED-ÉCHO. Les données sur les naissances provenaient de l'Institut de la statistique du Québec. RéSULTATS :: La prévalence annuelle moyenne pour 1000 naissances vivantes de sexe masculin est de 19,1 (IC à 95 % : 18,8-19,4) pour la cryptorchidie et 11,4 (IC à 95 % 11,1-11,6) pour l'hypospadias au Québec. Au cours de la période étudiée, la prévalence de cryptorchidie a légèrement diminué, alors que celle de l'hypospadias est demeurée stable. Comparativement à la province du Québec, des régions présentent une prévalence significativement différente de cryptorchidie et/ou d'hypospadias. . : Au Québec, la prévalence de cryptorchidie est en légère diminution alors que celle de l'hypospadias est stable. Des variations régionales significatives sont observables. D'autres études sont nécessaires afin d'évaluer l'hypothèse d'un lien avec les contaminants environnementaux en émergence. L'implantation d'un système de surveillance des anomalies congénitales permettrait une représentation plus valide de la situation.

  18. Make Earth science education as dynamic as Earth itself

    NASA Astrophysics Data System (ADS)

    Lautenbacher, Conrad C.; Groat, Charles G.

    2004-12-01

    The images of rivers spilling over their banks and washing away entire towns, buildings decimated to rubble by the violent shaking of the Earth's plates, and molten lava flowing up from inside the Earth's core are constant reminders of the power of the Earth. Humans are simply at the whim of the forces of Mother Nature—or are we? Whether it is from a great natural disaster, a short-term weather event like El Nino, or longer-term processes like plate tectonics, Earth processes affect us all. Yet,we are only beginning to scratch the surface of our understanding of Earth sciences. We believe the day will come when our understanding of these dynamic Earth processes will prompt better policies and decisions about saving lives and property. One key place to start is in America's classrooms.

  19. Le transfert de connaissances entre les mathematiques et les sciences. Une etude exploratoire aupres d'eleves de 4e secondaire

    NASA Astrophysics Data System (ADS)

    Samson, Ghislain

    2003-06-01

    Au moment ou dans plusieurs pays on travaille a refondre les programmes d'etudes, tant au primaire qu'au secondaire, l'interet pour le transfert renait. Un des concepts fondamentaux en apprentissage consiste en l'habilete a reutiliser de facon consciente et efficace un acquis d'une situation a une autre situation. Cette recherche emane de preoccupations professionnelles au moment ou le chercheur etait enseignant au secondaire. Au cours de ces annees, il lui a ete possible de constater que plusieurs eleves percevaient difficilement les liens presents entre les disciplines mathematiques et scientifiques. Des travaux en psychologie cognitive et plus particulierement selon une perspective du traitement de l'information ont servi de cadre de reference pour evaluer et analyser les capacites de transfert aupres d'eleves de 4e secondaire. Ce cadre de reference permet de formuler le principal objectif qui est de mieux comprendre le processus de transfert chez des eleves en situation de resolution de problemes scientifiques. Cette these s'interesse donc au transfert en tant que phenomene important du processus d'apprentissage au sens de l'integration. La methode de recherche choisie, de nature qualitative, est principalement axee sur l'evaluation de la capacite a transferer des connaissances lors d'une epreuve et d'un entretien. Pour evaluer ce potentiel de transfert, nous avons elabore deux outils: une epreuve en mathematiques et en sciences et un guide d'entretien. Pour la passation de l'epreuve, le chercheur a pu compter sur la collaboration de 130 sujets provenant de deux ecoles. L'entretien complete la prise de donnees avec 13 sujets ayant accepte de poursuivre l'etude. Les donnees recueillies par ces instruments font ensuite l'objet d'une analyse de contenu. En premier lieu, les verbatims de l'epreuve et de l'entretien ont ete transcrits, puis codifies. La correction des reponses fournies pour les problemes resolus s'est faite a partir d'une grille d

  20. ISS EarthKam: Taking Photos of the Earth from Space

    ERIC Educational Resources Information Center

    Haste, Turtle

    2008-01-01

    NASA is involved in a project involving the International Space Station (ISS) and an Earth-focused camera called EarthKam, where schools, and ultimately students, are allowed to remotely program the EarthKAM to take images. Here the author describes how EarthKam was used to help middle school students learn about biomes and develop their…

  1. Validation de la version francophone d’une échelle composite multidimensionnelle pour l’évaluation de la douleur postopératoire chez les chats

    PubMed Central

    Steagall, Paulo V.M.; Monteiro, Beatriz P.; Lavoie, Anne-Marie; Frank, Diane; Troncy, Eric; Luna, Stelio P.L.; Brondani, Juliana T.

    2017-01-01

    Résumé L’objectif de cette étude était de valider la version francophone de l’échelle composite multidimensionnelle de douleur UNESP-Botucatu (MCPS-Fr) chez les chats. Deux vétérinaires et une étudiante de médecine vétérinaire francophones ont identifié trois catégories de comportements distincts sur des vidéos : «les changements psychomoteurs», «la protection de la région douloureuse» et «les variables physiologiques». La cohérence interne était excellente (score total du coefficient alpha de Cronbach était de 0,94; 0,90; et 0,61, respectivement). La bonne concordance entre les évaluations à l’aveugle des observateurs et l’évaluateur de référence confirme la validité de cet instrument. La fiabilité inter- et intra-évaluateur était bonne à très bonne. Le point limite optimal pour l’analgésie de secours, identifié avec une courbe ROC, était au-delà de 7 (échelle allant de 0 à 30 points), avec une sensibilité de 97,8 % et une spécificité de 99,1 %. La MCPS-Fr est un outil valide et sensible pour l’évaluation de la douleur aiguë chez les chattes ayant subi une ovariohystérectomie. PMID:28042156

  2. Ancient Earth, Alien Earths Event

    NASA Image and Video Library

    2014-08-20

    Panelists discuss how research on early Earth could help guide our search for habitable planets orbiting other stars at the “Ancient Earth, Alien Earths” Event at NASA Headquarters in Washington, DC Wednesday, August 20, 2014. The event was sponsored by NASA, the National Science Foundation (NSF), and the Smithsonian Institution and was moderated by Dr. David H. Grinspoon, Senior Scientist at the Planetary Science Institute. Photo Credit: (NASA/Aubrey Gemignani)

  3. Ancient Earth, Alien Earths Event

    NASA Image and Video Library

    2014-08-20

    Dr. David H. Grinspoon, Senior Scientist, Planetary Science Institute, moderates a panel at the “Ancient Earth, Alien Earths” Event at NASA Headquarters in Washington, DC Wednesday, August 20, 2014. The event was sponsored by NASA, the National Science Foundation (NSF), and the Smithsonian Institution and highlighted how research on early Earth could help guide our search for habitable planets orbiting other stars. Photo Credit: (NASA/Aubrey Gemignani)

  4. Une version canadienne française du Lower Extremity Functional Scale (LEFS) : L'Échelle fonctionnelle des membres inférieurs (ÉFMI), partie I

    PubMed Central

    René, Frédéric; Casimiro, Lynn; Tremblay, Manon; Lefebvre, Annabelle; Beaudouin, Martine; Belliveau, Véronik; Bergeron, Louis-Philippe

    2011-01-01

    RÉSUMÉ Introduction : Le Rehabilitation Network of Ottawa-Carleton (RENOC) recommande à ses établissements de santé d'utiliser le Lower Extremity Functional Scale (LEFS). Puisque le RENOC dessert une clientèle anglophone et francophone, il s'imposait de traduire le LEFS pour l'évaluation de la clientèle francophone. But : Produire une traduction canadienne-française du LEFS sous l'appellation proposée « Échelle fonctionnelle des membres inférieurs (ÉFMI) » et examiner la validité de son contenu. Méthodologie : Nous avons utilisé une approche modifiée de la méthodologie de validation transculturelle de questionnaires de Vallerand (1989). Une traduction renversée parallèle du LEFS a d'abord été complétée. Ensuite, un comité d'experts a examiné les deux versions préliminaires et a créé la première version expérimentale de l'ÉFMI. Cette version fut évaluée par un deuxième comité d'experts, dont les commentaires menèrent à une deuxième version expérimentale. Finalement, 35 professionnels de la réadaptation évaluèrent la version expérimentale de l'ÉFMI sur une échelle d'ambiguïté et proposèrent les modifications finales. Résultats : Pour les différents énoncés de la version finale de l'ÉFMI, les moyennes sur l'échelle d'ambiguïté démontrent un niveau d'ambiguïté relativement faible puisqu'elles varient entre 1 et 2.54. Conclusion : Les quatre étapes rigoureuses du processus ont permis de produire une version valide du LEFS en français. PMID:22379265

  5. Une colite à CMV révélant un lupus érythémateux systémique

    PubMed Central

    Ben Ghorbel, Imed; Boussetta, Najeh; Boubaker, Jalel; Zehani, Alia; Lamloum, Mounir; Houman, Mohamed Habib

    2014-01-01

    Le cytomégalovirus (CMV) est responsable d'infections souvent asymptomatiques chez les immunocompétents mais également d'infections graves chez les immunodéprimés notamment chez les patients lupiques. La réactivation du CMV au cours du lupus est une complication fréquente mais rarement inaugurale. Nous rapportons l'observation d'un patient ayant présenté une colite à CMV révélatrice d'un lupus érythémateux systémique. Le diagnostic a été retenu sur les données sérologiques, de la biopsie colique et la bonne évolution après un traitement par ganciclovir. PMID:25977743

  6. La prévention des blessures chez les enfants et les adolescents : une démarche de santé publique

    PubMed Central

    Yanchar, Natalie L; Warda, Lynne J; Fuselli, Pamela

    2012-01-01

    RÉSUMÉ La majorité des blessures dont sont victimes les enfants et les adolescents sont évitables. Le présent document de principes contient des renseignements généraux, des conseils et une déclaration d’engagement à l’égard de la prévention des blessures au Canada. Il sert de base sur laquelle construire en s’attardant d’abord aux définitions, à l’étendue et aux priorités en matière de prévention des blessures. Il contient également une description du fardeau et du profil des blessures non intentionnelles, de même que les principes d’interventions de prévention efficaces. La version intégrale renferme une liste de ressources en vue d’obtenir des données et de l’information probante (www.cps.ca). Enfin, le présent document de principes peut être utilisé pour la défense généralisée de la prévention des blessures.

  7. Digital Earth for Earth Sciences and Public Education

    NASA Astrophysics Data System (ADS)

    Foresman, T. W.

    2006-12-01

    Buckminster Fuller was an early advocate for better comprehension of the planet and its resources related to human affairs. A comprehensive vision was articulated by a US Vice President and quickly adopted by the world's oldest country China.. Digital Earth brings fresh perspective on the current state of affairs and connects citizens with scientists through the applications of 3D visualization, spinning globes, virtual Earths, and the current collaboration with Virtual Globes. The prowess of Digital Earth technology has been so successful in both understanding and communicating the more challenging topics for global change and climate change phenomena that China has assigned it priority status with the Ministry of Science and Technology and the Chinese Academy of Sciences. New Zealand has recently begun to adjust its national strategies for sustainability with the technologies of Digital Earth. A comprehensive coverage of the results compiled over the past seven years is presented to place a foundation for the science and engineering community to prepare to align with this compelling science enterprise as a fundamental new paradigm for the registration, storage, and access of science data and information through the emerging Digital Earth Exchange under protocols developed for the Digital Earth Reference Model.

  8. Etude des phenomenes chimiques au contact entre le bloc cathodique et la barre collectrice d'une cellule d'electrolyse d'aluminium

    NASA Astrophysics Data System (ADS)

    Lebeuf, Martin

    La production d'aluminium est une industrie importante au Québec. Les propriétés de ce métal le vouent à de multiples usages présents et futurs dans le cadre d'une économie moderne durable. Toutefois, le procédé Hall-Héroult est très énergivore et des progrès demeurent donc nécessaires pour en diminuer les coûts financiers et environnementaux. Parmi les améliorations envisageables de la cellule d'électrolyse se trouve le contact entre la cathode et la barre collectrice, qui doit offrir une faible résistivité au passage du courant électrique. En cours d'opération de la cellule, ce contact a tendance à se dégrader, générant des pertes énergétiques significatives. Les causes de cette dégradation, pouvant provenir de phénomènes chimiques, thermiques, mécaniques et/ou électriques, demeurent mal comprises. Le but du présent projet était donc d'étudier les phénomènes chimiques se produisant au contact bloc-barre de la cellule d'électrolyse Hall-Héroult. En premier lieu, un aspect crucial à considérer est la pénétration du bain électrolytique dans la cathode, car des composés de bain atteignent éventuellement la barre collectrice et peuvent y réagir. A cet effet, une méthode novatrice a été développée afin d'étudier les cathodes et la pénétration du bain dans celles-ci à l'aide de la microtomographie à rayons X. Cette méthode rapide et efficace s'est avérée fort utile dans le projet et a un potentiel important pour l'étude future des cathodes et des phénomènes qui s'y produisent. Ensuite, une cellule d'électrolyse rectangulaire à petite échelle a été développée. Plusieurs phénomènes observés 'en industrie sur des autopsies de cellules post-opération et rapportés dans la littérature ont été reproduis avec succès à l'aide de cette cellule expérimentale. Puis, des tests sans électrolyse, ciblant l'effet du bain électrolytique sur l'acier, ont aussi été conçus et complétés afin de s

  9. Why Earth Science?

    ERIC Educational Resources Information Center

    Smith, Michael J.

    2004-01-01

    This article briefly describes Earth science. The study of Earth science provides the foundation for an understanding of the Earth, its processes, its resources, and its environment. Earth science is the study of the planet in its entirety, how its lithosphere, atmosphere, hydrosphere, and biosphere work together as systems and how they affect…

  10. Étalement d'une goutte stratifiée incompressible

    NASA Astrophysics Data System (ADS)

    de Gennes, Pierre-Gilles; Cazabat, Anne-Marie

    L'étalement de films ultraminces de liquides simples sur une surface lisse horizontale conduit souvent à des gouttes à gradins d'une épaisseur moléculaire ([1]-[3]). Nous construisons ici un modèle pour la dynamique de l'étalement, en supposant que : (a) chaque gradin est un liquide bidimensionnel incompressible; (b) les molécules de la n-ième couche sont soumises à un potentiel (Wn) qui exprime leurs interactions à longue portée avec le solide; (c) on a un écoulement parallèle de cisaillement, et un écoulement normal de perméation. La perméation intervient seulement dans un certain « ruban » de largeur ξ sur le bord de chaque gradin. Dans le cas usuel, où le rayon du n-ième gradin Rn est trs supérieur à ξ, la dissipation est dominée par le cisaillement, et on arrive à des lois simples pour la vitesse de dilatation (ou de contraction) dotR_n. Very thin films of simple liquids often spread with well defined steps of molecular thickness ([1]-[3]). We construct a model for the dynamics of spreading assuming that: (a) each layer is an incompressible, 2 dimensional fluid; (b) the molecules in the (nth) layer experience a long range potential (e.g. Van der Waals) from the solid; (c) two types of flow occur: shear between layers and permeation normal to the layers. We find that permeation is important only in an annulus of small size ξ near each step. Between steps, the viscous effects in simple shear dominate, and this leads to simple laws for the dilation (or contraction) of the various layers.

  11. Approche au diagnostic de la maladie cœliaque chez les patients ayant une faible densité minérale osseuse ou des fractures de fragilité

    PubMed Central

    Rios, Lorena P.; Khan, Aliya; Sultan, Muhammad; McAssey, Karen; Fouda, Mona A.; Armstrong, David

    2013-01-01

    Résumé Objectif Présenter aux cliniciens une mise à jour sur le diagnostic de la maladie cœliaque (MC), ainsi que des recommandations sur les indications de procéder au dépistage de la MC chez les patients présentant une faible densité minérale osseuse (DMO) ou des fractures de fragilité. Qualité des données Un groupe de travail multidisciplinaire a élaboré des questions cliniquement pertinentes relativement au diagnostic de la MC servant de fondement à une recherche documentaire dans les bases de données MEDLINE, EMBASE et CENTRAL (de janvier 2000 à janvier 2009) à l’aide des mots clés en anglais celiac disease, osteoporosis, osteopenia, low bone mass et fracture. Les ouvrages scientifiques existants comportent des études de niveaux I et II. Message principal La prévalence estimée de la MC asymptomatique est de 2 % à 3 % chez les personnes qui ont une faible DMO. Par ailleurs, un dépistage ciblé est recommandé pour les patients qui ont des T-scores de −1,0 ou moins à la colonne vertébrale ou aux hanches ou des antécédents de fractures de fragilité associées à des symptômes ou à des problèmes reliés à la MC, des antécédents familiaux de MC ou de bas niveaux de calcium urinaire, une insuffisance en vitamine D et des niveaux à la hausse d’hormones parathyroïdiennes en dépit d’un apport suffisant en calcium et en vitamine D. Le dépistage de la MC devrait se faire pendant que le sujet consomme un régime alimentaire contenant du gluten. On procède au dépistage initial par le dosage d’immunoglobuline (Ig) A antitransglutaminase en utilisant la transglutaminase tissulaire humaine recombinante ou une autre transglutaminase tissulaire, en association avec l’immunofluorescence des IgA anti-endomysium. Une biopsie du duodénum est nécessaire pour confirmer le diagnostic de la MC. Le typage des antigènes des leucocytes humains peut aider à confirmer ou à exclure le diagnostic de la MC dans les cas où la s

  12. Une présentation atypique de la maladie cœliaque: l'occlusion de la veine centrale de la rétine

    PubMed Central

    Jomni, Taieb; Bellakhal, Syrine; Abouda, Maher; Abdelaali, Imene; Douggui, Hédi

    2015-01-01

    Parmi les complications thrombotiques de la maladie cœliaque l'occlusion de la veine centrale de la rétine a été exceptionnellement décrite. Nous rapportons l'observation d'une patiente âgée de 27 ans chez qui le diagnostic de maladie cœliaque a été porté dans le cadre du bilan étiologique d'une occlusion de la veine centrale de la rétine. L'interrogatoire ne révélait pas de diarrhée chronique ou de douleurs abdominales. La présence d'un amaigrissement, d'une anémie ferriprive et d'une hypocholestérolémie ont permis l'orientation vers la maladie cœliaque. La positivité des anticorps anti endomysium et la biopsie duodénale montrant l'atrophie villositaire confirmaient ce diagnostic. Le régime sans gluten associé à un traitement par aspirine avait partiellement amélioré l'acuité visuelle chez notre patiente. Cette présentation atypique de la maladie cœliaque souligne la diversité des manifestations extra-digestives au cours de cette maladie et l'intérêt de penser à la maladie cœliaque même lorsque ces manifestations sont inaugurales. PMID:26966496

  13. Crew Earth Observations

    NASA Technical Reports Server (NTRS)

    Runco, Susan

    2009-01-01

    Crew Earth Observations (CEO) takes advantage of the crew in space to observe and photograph natural and human-made changes on Earth. The photographs record the Earth's surface changes over time, along with dynamic events such as storms, floods, fires and volcanic eruptions. These images provide researchers on Earth with key data to better understand the planet.

  14. Earth Rotation

    NASA Technical Reports Server (NTRS)

    Dickey, Jean O.

    1995-01-01

    The study of the Earth's rotation in space (encompassing Universal Time (UT1), length of day, polar motion, and the phenomena of precession and nutation) addresses the complex nature of Earth orientation changes, the mechanisms of excitation of these changes and their geophysical implications in a broad variety of areas. In the absence of internal sources of energy or interactions with astronomical objects, the Earth would move as a rigid body with its various parts (the crust, mantle, inner and outer cores, atmosphere and oceans) rotating together at a constant fixed rate. In reality, the world is considerably more complicated, as is schematically illustrated. The rotation rate of the Earth's crust is not constant, but exhibits complicated fluctuations in speed amounting to several parts in 10(exp 8) [corresponding to a variation of several milliseconds (ms) in the Length Of the Day (LOD) and about one part in 10(exp 6) in the orientation of the rotation axis relative to the solid Earth's axis of figure (polar motion). These changes occur over a broad spectrum of time scales, ranging from hours to centuries and longer, reflecting the fact that they are produced by a wide variety of geophysical and astronomical processes. Geodetic observations of Earth rotation changes thus provide insights into the geophysical processes illustrated, which are often difficult to obtain by other means. In addition, these measurements are required for engineering purposes. Theoretical studies of Earth rotation variations are based on the application of Euler's dynamical equations to the problem of finding the response of slightly deformable solid Earth to variety of surface and internal stresses.

  15. EarthChem and SESAR: Data Resources and Interoperability for EarthScope Cyberinfrastructure

    NASA Astrophysics Data System (ADS)

    Lehnert, K. A.; Walker, D.; Block, K.; Vinay, S.; Ash, J.

    2008-12-01

    Data management within the EarthScope Cyberinfrastructure needs to pursue two goals in order to advance and maximize the broad scientific application and impact of the large volumes of observational data acquired by EarthScope facilities: (a) to provide access to all data acquired by EarthScope facilities, and to promote their use by broad audiences, and (b) to facilitate discovery of, access to, and integration of multi-disciplinary data sets that complement EarthScope data in support of EarthScope science. EarthChem and SESAR, the System for Earth Sample Registration, are two projects within the Geoinformatics for Geochemistry program that offer resources for EarthScope CI. EarthChem operates a data portal that currently provides access to >13 million analytical values for >600,000 samples, more than half of which are from North America, including data from the USGS and all data from the NAVDAT database, a web-accessible repository for age, chemical and isotopic data from Mesozoic and younger igneous rocks in western North America. The new EarthChem GEOCHRON database will house data collected in association with GeoEarthScope, storing and serving geochronological data submitted by participating facilities. The EarthChem Deep Lithosphere Dataset is a compilation of petrological data for mantle xenoliths, initiated in collaboration with GeoFrame to complement geophysical endeavors within EarthScope science. The EarthChem Geochemical Resource Library provides a home for geochemical and petrological data products and data sets. Parts of the digital data in EarthScope CI refer to physical samples such as drill cores, igneous rocks, or water and gas samples, collected, for example, by SAFOD or by EarthScope science projects and acquired through lab-based analysis. Management of sample-based data requires the use of global unique identifiers for samples, so that distributed data for individual samples generated in different labs and published in different papers can be

  16. Ancient Earth, Alien Earths Event

    NASA Image and Video Library

    2014-08-20

    An audience member asks the panelists a question at the “Ancient Earth, Alien Earths” Event at NASA Headquarters in Washington, DC Wednesday, August 20, 2014. The event was sponsored by NASA, the National Science Foundation (NSF), and the Smithsonian Institution and was moderated by Dr. David H. Grinspoon, Senior Scientist at the Planetary Science Institute. Six scientists discussed how research on early Earth could help guide our search for habitable planets orbiting other stars. Photo Credit: (NASA/Aubrey Gemignani)

  17. Les traumatismes de l’étage antérieur de la base du crane: à propos d'une série de 136 cas

    PubMed Central

    Bouchaouch, Abdelali; Hassani, Fahd Derkaoui; Abboud, Hilal; Mukengeshay, Jeff Ntalaja; El Fatemi, Nizare; Gana, Rachid; El Maaqili, Moulay Rchid; El Abbadi, Najia; Bellakhdar, Fouad

    2015-01-01

    Les traumatismes de l’étage antérieur de la base du crâne représentent 15 à 20% des traumatismes crâniens en général. Ils menacent les structures neuro-encéphaliques sus jacentes et sont très souvent responsables de brèches ostéo-méningées exposant au risque infectieux. Notre travail a concerné 136 dossiers exploitables de traumatisme de l’étage antérieur de la base du crâne colligés sur une période de 10 ans entre janvier 2003 et décembre 2012. Le diagnostic a été suspecté devant les signes cliniques évocateurs (ecchymose péri-orbitaire, rhinorrhée…) et a été confirmé dans la plupart des cas par la TDM. Le traitement idéal est la fermeture chirurgicale de la brèche en association aux moyens médicaux (vaccination, anti-épileptiques, mesures de réanimation…) Le moment idéal de la réparation est au-delà de la 72ème heure après la diminution de l'oedème cérébral en cas d'absence d'une lésion intracrânienne nécessitant une intervention en urgence. Notre équipe ne pratiquant pas la voie endoscopique, l'abord frontal est souvent indiqué. Le pronostic dépend des lésions cérébrales associées et surtout de la présence d'une brèche dont le diagnostic et la réparation doivent être les plus rapides et les plus précis possibles. Ainsi toute rhinorrhée post-traumatique nécessite une exploration systématique, le timing idéal: c'est la disparition de l'oedème cérébral pour faciliter l'exploration, ceci est en général possible à partir de la 72ème heure sauf dans les cas associés à une autre lésion intra crânienne nécessitant une exploration en urgence. PMID:26327992

  18. Earth Science Europe "Is Earth Science Europe an interesting and useful construct?"

    NASA Astrophysics Data System (ADS)

    Ludden, John

    2015-04-01

    In 2014 we managed to have a group of earth scientists from across the spectrum: from academic, survey, industry and government, pull together to create the first output for Earth Science Europe http://www.bgs.ac.uk/earthScienceEurope/downloads/EarthScienceEuropeBrochure.pdf In this document we stated that Earth scientists need a united, authoritative voice to enhance the status and impact of Earth science across Europe. The feeling was that there were many diverse infrastructure and research initiatives spanning the terrestrial and oceanic realms and science ranged from historical geology to active dynamics on Earth, and that a level of coordination and mutual knowledge sharing was necessary. In addition to a better understanding of the Earth in general, we thought there was a need to have Earth Science Europe develop a strategic research capacity in geohazards, georesources and environmental earth sciences, through a roadmap addressing fundamental and societal challenges. This would involve a robust research infrastructure to deliver strategic goals, enabling inspirational research and promoting solutions to societal challenges. In this talk I will propose some next steps and discuss what this "authoritative voice" could look like and ask the question - "is Earth Science Europe and interesting and useful concept?"

  19. Earth Reflectivity from Deep Space Climate Observatory (DSCOVR) Earth Polychromatic Camera (EPIC)

    NASA Astrophysics Data System (ADS)

    Song, W.; Knyazikhin, Y.; Wen, G.; Marshak, A.; Yan, G.; Mu, X.; Park, T.; Chen, C.; Xu, B.; Myneni, R. B.

    2017-12-01

    Earth reflectivity, which is also specified as Earth albedo or Earth reflectance, is defined as the fraction of incident solar radiation reflected back to space at the top of the atmosphere. It is a key climate parameter that describes climate forcing and associated response of the climate system. Satellite is one of the most efficient ways to measure earth reflectivity. Conventional polar orbit and geostationary satellites observe the Earth at a specific local solar time or monitor only a specific area of the Earth. For the first time, the NASA's Earth Polychromatic Imaging Camera (EPIC) onboard NOAA's Deep Space Climate Observatory (DSCOVR) collects simultaneously radiance data of the entire sunlit earth at 8 km resolution at nadir every 65 to 110 min. It provides reflectivity images in backscattering direction with the scattering angle between 168º and 176º at 10 narrow spectral bands in ultraviolet, visible, and near-Infrared (NIR) wavelengths. We estimate the Earth reflectivity using DSCOVR EPIC observations and analyze errors in Earth reflectivity due to sampling strategy of polar orbit Terra/Aqua MODIS and geostationary Goddard Earth Observing System-R series missions. We also provide estimates of contributions from ocean, clouds, land and vegetation to the Earth reflectivity. Graphic abstract shows enhanced RGB EPIC images of the Earth taken on July-24-2016 at 7:04GMT and 15:48 GMT. Parallel lines depict a 2330 km wide Aqua MODIS swath. The plot shows diurnal courses of mean Earth reflectance over the Aqua swath (triangles) and the entire image (circles). In this example the relative difference between the mean reflectances is +34% at 7:04GMT and -16% at 15:48 GMT. Corresponding daily averages are 0.256 (0.044) and 0.231 (0.025). The relative precision estimated as root mean square relative error is 17.9% in this example.

  20. Earth Observations

    NASA Image and Video Library

    2010-06-16

    ISS024-E-006136 (16 June 2010) --- Polar mesospheric clouds, illuminated by an orbital sunrise, are featured in this image photographed by an Expedition 24 crew member on the International Space Station. Polar mesospheric, or noctilucent (?night shining?), clouds are observed from both Earth?s surface and in orbit by crew members aboard the space station. They are called night-shining clouds as they are usually seen at twilight. Following the setting of the sun below the horizon and darkening of Earth?s surface, these high clouds are still briefly illuminated by sunlight. Occasionally the ISS orbital track becomes nearly parallel to Earth?s day/night terminator for a time, allowing polar mesospheric clouds to be visible to the crew at times other than the usual twilight due to the space station altitude. This unusual photograph shows polar mesospheric clouds illuminated by the rising, rather than setting, sun at center right. Low clouds on the horizon appear yellow and orange, while higher clouds and aerosols are illuminated a brilliant white. Polar mesospheric clouds appear as light blue ribbons extending across the top of the image. These clouds typically occur at high latitudes of both the Northern and Southern Hemispheres, and at fairly high altitudes of 76?85 kilometers (near the boundary between the mesosphere and thermosphere atmospheric layers). The ISS was located over the Greek island of Kos in the Aegean Sea (near the southwestern coastline of Turkey) when the image was taken at approximately midnight local time. The orbital complex was tracking northeastward, nearly parallel to the terminator, making it possible to observe an apparent ?sunrise? located almost due north. A similar unusual alignment of the ISS orbit track, terminator position, and seasonal position of Earth?s orbit around the sun allowed for striking imagery of polar mesospheric clouds over the Southern Hemisphere earlier this year.

  1. Ancient Earth, Alien Earths Event

    NASA Image and Video Library

    2014-08-20

    Dr. Phoebe Cohen, Professor of Geosciences, Williams College, speaks on a panel at the “Ancient Earth, Alien Earths” Event at NASA Headquarters in Washington, DC Wednesday, August 20, 2014. The event was sponsored by NASA, the National Science Foundation (NSF), and the Smithsonian Institution and was moderated by Dr. David H. Grinspoon, Senior Scientist at the Planetary Science Institute. Six scientists discussed how research on early Earth could help guide our search for habitable planets orbiting other stars. Photo Credit: (NASA/Aubrey Gemignani)

  2. Ancient Earth, Alien Earths Event

    NASA Image and Video Library

    2014-08-20

    Dr. Christopher House, Professor of Geosciences, Pennsylvania State University, speaks on a panel at the “Ancient Earth, Alien Earths” Event at NASA Headquarters in Washington, DC Wednesday, August 20, 2014. The event was sponsored by NASA, the National Science Foundation (NSF), and the Smithsonian Institution and was moderated by Dr. David H. Grinspoon, Senior Scientist at the Planetary Science Institute. Six scientists discussed how research on early Earth could help guide our search for habitable planets orbiting other stars. Photo Credit: (NASA/Aubrey Gemignani)

  3. Ancient Earth, Alien Earths Event

    NASA Image and Video Library

    2014-08-20

    Dr. Dawn Sumner, Professor of Geology, UC Davis, speaks on a panel at the “Ancient Earth, Alien Earths” Event at NASA Headquarters in Washington, DC Wednesday, August 20, 2014. The event was sponsored by NASA, the National Science Foundation (NSF), and the Smithsonian Institution and was moderated by Dr. David H. Grinspoon, Senior Scientist at the Planetary Science Institute. Six scientists discussed how research on early Earth could help guide our search for habitable planets orbiting other stars. Photo Credit: (NASA/Aubrey Gemignani)

  4. Ancient Earth, Alien Earths Event

    NASA Image and Video Library

    2014-08-20

    Dr. Timothy Lyons, Professor of Biogeochemistry, UC Riverside, speaks on a panel at the “Ancient Earth, Alien Earths” Event at NASA Headquarters in Washington, DC Wednesday, August 20, 2014. The event was sponsored by NASA, the National Science Foundation (NSF), and the Smithsonian Institution and was moderated by Dr. David H. Grinspoon, Senior Scientist at the Planetary Science Institute. Six scientists discussed how research on early Earth could help guide our search for habitable planets orbiting other stars. Photo Credit: (NASA/Aubrey Gemignani)

  5. EarthLabs - Investigating Hurricanes: Earth's Meteorological Monsters

    NASA Astrophysics Data System (ADS)

    McDaris, J. R.; Dahlman, L.; Barstow, D.

    2007-12-01

    Earth science is one of the most important tools that the global community needs to address the pressing environmental, social, and economic issues of our time. While, at times considered a second-rate science at the high school level, it is currently undergoing a major revolution in the depth of content and pedagogical vitality. As part of this revolution, labs in Earth science courses need to shift their focus from cookbook-like activities with known outcomes to open-ended investigations that challenge students to think, explore and apply their learning. We need to establish a new model for Earth science as a rigorous lab science in policy, perception, and reality. As a concerted response to this need, five states, a coalition of scientists and educators, and an experienced curriculum team are creating a national model for a lab-based high school Earth science course named EarthLabs. This lab course will comply with the National Science Education Standards as well as the states' curriculum frameworks. The content will focus on Earth system science and environmental literacy. The lab experiences will feature a combination of field work, classroom experiments, and computer access to data and visualizations, and demonstrate the rigor and depth of a true lab course. The effort is being funded by NOAA's Environmental Literacy program. One of the prototype units of the course is Investigating Hurricanes. Hurricanes are phenomena which have tremendous impact on humanity and the resources we use. They are also the result of complex interacting Earth systems, making them perfect objects for rigorous investigation of many concepts commonly covered in Earth science courses, such as meteorology, climate, and global wind circulation. Students are able to use the same data sets, analysis tools, and research techniques that scientists employ in their research, yielding truly authentic learning opportunities. This month-long integrated unit uses hurricanes as the story line by

  6. EarthExplorer

    USGS Publications Warehouse

    Houska, Treva

    2012-01-01

    The EarthExplorer trifold provides basic information for on-line access to remotely-sensed data from the U.S. Geological Survey Earth Resources Observation and Science (EROS) Center archive. The EarthExplorer (http://earthexplorer.usgs.gov/) client/server interface allows users to search and download aerial photography, satellite data, elevation data, land-cover products, and digitized maps. Minimum computer system requirements and customer service contact information also are included in the brochure.

  7. Comparison of Low Earth Orbit and Geosynchronous Earth Orbits

    NASA Technical Reports Server (NTRS)

    Drummond, J. E.

    1980-01-01

    The technological, environmental, social, and political ramifications of low Earth orbits as compared to geosynchronous Earth orbits for the solar power satellite (SPS) are assessed. The capital cost of the transmitting facilities is dependent on the areas of the antenna and rectenna relative to the requirement of high efficiency power transmission. The salient features of a low orbit Earth orbits are discussed in terms of cost reduction efforts.

  8. Ancient Earth, Alien Earths Event

    NASA Image and Video Library

    2014-08-20

    Dr. Shawn Domagal-Goldman, Research Space Scientist, NASA Goddard Space Flight Center, speaks on a panel at the “Ancient Earth, Alien Earths” Event at NASA Headquarters in Washington, DC Wednesday, August 20, 2014. The event was sponsored by NASA, the National Science Foundation (NSF), and the Smithsonian Institution and was moderated by Dr. David H. Grinspoon, Senior Scientist at the Planetary Science Institute. Six scientists discussed how research on early Earth could help guide our search for habitable planets orbiting other stars. Photo Credit: (NASA/Aubrey Gemignani)

  9. Earth - South America (first frame of Earth Spin Movie)

    NASA Technical Reports Server (NTRS)

    1990-01-01

    This color image of the Earth was obtained by Galileo at about 6:10 a.m. Pacific Standard Time on Dec. 11, 1990, when the spacecraft was about 1.3 million miles from the planet during the first of two Earth flybys on its way to Jupiter. The color composite used images taken through the red, green and violet filters. South America is near the center of the picture, and the white, sunlit continent of Antarctica is below. Picturesque weather fronts are visible in the South Atlantic, lower right. This is the first frame of the Galileo Earth spin movie, a 500- frame time-lapse motion picture showing a 25-hour period of Earth's rotation and atmospheric dynamics.

  10. The Dynamic Earth.

    ERIC Educational Resources Information Center

    Siever, Raymond

    1983-01-01

    Discusses how the earth is a dynamic system that maintains itself in a steady state. Areas considered include large/small-scale earth motions, geologic time, rock and hydrologic cycles, and other aspects dealing with the changing face of the earth. (JN)

  11. Atteinte cérébro-méningée multiple révélant une Tuberculose multifocale chez un immunocompétent

    PubMed Central

    Boulahri, Tarik; Taous, Abdellah; Berri, Maha Aït; Traibi, Imane; Rouimi, Abdelhadi

    2016-01-01

    La Tuberculose constitue un problème de santé publique au Maroc. L’atteinte du système nerveux central est néanmoins rare, survenant dans un contexte de tuberculose multifocale ou miliaire tuberculeuse. Cependant elle peut être un mode de révélation même chez un sujet immunocompétent. Nous rapportons le cas d’un homme de 30 ans qui avait présenté un trouble du langage évoluant dans un contexte d’altération de l’état général avec à l’examen clinique une aphasie motrice de type Broca, un syndrome pyramidal latéralisé à droite et des adénopathies latéro-cérvicales. la sérologie HIV était négative. L’IRM cérébrale: montrait des lésions associant des tuberculomes intracrâniens multiple et une image de méningo-encéphalite. La TDM thoracique montrait de multiples micronodules pulmonaires, une image cavitaire à paroi épaissie et DDB du fowler droit et du culmen. La biopsie des ganglions lymphatiques révélait la présence de granulome typique de tuberculose. Le diagnostic de tuberculose multifocale fut retenu et le patient fut mis sous traitement anti-bacillaire associé à une corticothérapie avec une bonne évolution clinico-radiologique. Cette observation est particulière par l’aspect et le siège des lésions tuberculeuse retrouvées à l’imagerie cérébrale, par l’absence d’immunodéficience, par la bonne évolution sous traitement et souligne l’intérêt de rechercher activement par un bilan exhaustif une infection tuberculeuse extra-cérébrale associée devant toute lésion cérébro-méningée évocatrice de tuberculose. PMID:28293347

  12. Chéilite tuberculeuse révélant une tuberculose pulmonaire

    PubMed Central

    Bricha, Myriem; Slimani, Hajar; Hammi, Sanae; Bourkadi, Jamal Eddine

    2016-01-01

    La tuberculose de la cavité buccale reste rare. Elle admet un polymorphisme clinique et pose avant tout un problème de diagnostic. Nous rapportons le cas d'un homme de 42 ans présentant une chéilite tuberculeuse. L’intérêt de cette présentation est d’attirer l’attention sur la tuberculose que l’on peut retrouver de façon exceptionnelle dans certaines localisations, comme la lèvre buccale. PMID:27795773

  13. Building a Dashboard of the Planet with Google Earth and Earth Engine

    NASA Astrophysics Data System (ADS)

    Moore, R. T.; Hancher, M.

    2016-12-01

    In 2005 Google Earth, a popular 3-D virtual globe, was first released. Scientists immediately recognized how it could be used to tell stories about the Earth. From 2006 to 2009, the "Virtual Globes" sessions of AGU included innovative examples of scientists and educators using Google Earth, and since that time it has become a commonplace tool for communicating scientific results. In 2009 Google Earth Engine, a cloud-based platform for planetary-scale geospatial analysis, was first announced. Earth Engine was initially used to extract information about the world's forests from raw Landsat data. Since then, the platform has proven highly effective for general analysis of georeferenced data, and users have expanded the list of use cases to include high-impact societal issues such as conservation, drought, disease, food security, water management, climate change and environmental monitoring. To support these use cases, the platform has continuously evolved with new datasets, analysis functions, and user interface tools. This talk will give an overview of the latest Google Earth and Earth Engine functionality that allow partners to understand, monitor and tell stories about of our living, breathing Earth. https://earth.google.com https://earthengine.google.com

  14. Silence et divulgation dans des familles d’adolescents vivant avec le VIH depuis la naissance : une exploration qualitative

    PubMed Central

    Proulx-Boucher, Karène; Blais, Martin; Fernet, Mylène; Richard, Marie-Ève; Otis, Joanne; Josy Lévy, Joseph; Samson, Johanne; Lapointe, Normand; Morin, Guylaine; Thériault, Jocelyne; Trottier, Germain

    2011-01-01

    OBJECTIF : Les études ciblant les enfants nés avec le VIH se sont principalement intéressées à la période précédant l’annonce du diagnostic à l’enfant. L’objectif de cette étude est d’explorer les dynamiques de communication intrafamiliale suivant l’annonce du diagnostic. MÉTHODOLOGIE : Vingt-neuf jeunes (de dix à 18 ans) vivant avec le VIH depuis la naissance ont accordé des entrevues individuelles semi-dirigées portant sur : 1) le dévoilement du statut sérologique, 2) leurs relations familiales et 3) l’éducation sexuelle en milieu familial. Les témoignages ont fait l’objet d’une analyse de contenu. RÉSULTATS : Les jeunes ont appris en moyenne à l’âge de 11 ans leur diagnostic VIH+. La dynamique qui s’installe après cette annonce apparaît régie par le silence : les échanges qui s’ensuivent portent en majorité sur des questions relatives à la médication et à la prévention d’une transmission sexuelle du virus. Ce silence préserverait l’équilibre familial en occupant trois fonctions : protéger la mère d’un sentiment de culpabilité à l’égard de la transmission, assurer l’harmonie familiale, se sentir normal face aux autres. Le diagnostic de l’adolescent n’est généralement pas révélé à la famille élargie, préservant ainsi leur intégration au sein de la famille en les protégeant du rejet, de la trahison et du jugement. EXPOSÉ : Les fonctions du silence et du secret occupent une place stabilisatrice importante au sein de la famille. Toutefois, elles contribuent à isoler les adolescents d’une forme de soutien affectif dont ils ont pourtant besoin. Des pistes d’intervention sont suggérées. PMID:22851894

  15. Student Geoscientists Explore the Earth during Earth Science Week 2005

    ERIC Educational Resources Information Center

    Benbow, Ann E.; Camphire, Geoff

    2005-01-01

    Taking place October 9-15, Earth Science Week 2005 will celebrate the theme "Geoscientists Explore the Earth." The American Geological Institute (AGI) is organizing the event, as always, to help people better understand and appreciate the Earth sciences and to encourage stewardship of the planet. This year, the focus will be on the wide range of…

  16. Earth analysis methods, subsurface feature detection methods, earth analysis devices, and articles of manufacture

    DOEpatents

    West, Phillip B [Idaho Falls, ID; Novascone, Stephen R [Idaho Falls, ID; Wright, Jerry P [Idaho Falls, ID

    2012-05-29

    Earth analysis methods, subsurface feature detection methods, earth analysis devices, and articles of manufacture are described. According to one embodiment, an earth analysis method includes engaging a device with the earth, analyzing the earth in a single substantially lineal direction using the device during the engaging, and providing information regarding a subsurface feature of the earth using the analysis.

  17. Earth analysis methods, subsurface feature detection methods, earth analysis devices, and articles of manufacture

    DOEpatents

    West, Phillip B [Idaho Falls, ID; Novascone, Stephen R [Idaho Falls, ID; Wright, Jerry P [Idaho Falls, ID

    2011-09-27

    Earth analysis methods, subsurface feature detection methods, earth analysis devices, and articles of manufacture are described. According to one embodiment, an earth analysis method includes engaging a device with the earth, analyzing the earth in a single substantially lineal direction using the device during the engaging, and providing information regarding a subsurface feature of the earth using the analysis.

  18. Earth horizon modeling and application to static Earth sensors on TRMM spacecraft

    NASA Technical Reports Server (NTRS)

    Keat, J.; Challa, M.; Tracewell, D.; Galal, K.

    1995-01-01

    Data from Earth sensor assemblies (ESA's) often are used in the attitude determination (AD) for both spinning and Earth-pointing spacecraft. The ESA's on previous such spacecraft for which the ground-based AD operation was performed by the Flight Dynamics Division (FDD) used the Earth scanning method. AD on such spacecraft requires a model of the shape of the Earth disk as seen from the spacecraft. AD accuracy requirements often are too severe to permit Earth oblateness to be ignored when modeling disk shape. Section 2 of this paper reexamines and extends the methods for Earth disk shape modeling employed in AD work at FDD for the past decade. A new formulation, based on a more convenient Earth flatness parameter, is introduced, and the geometric concepts are examined in detail. It is shown that the Earth disk can be approximated as an ellipse in AD computations. Algorithms for introducing Earth oblateness into the AD process for spacecraft carrying scanning ESA's have been developed at FDD and implemented into the support systems. The Tropical Rainfall Measurement Mission (TRMM) will be the first spacecraft with AD operation performed at FDD that uses a different type of ESA - namely, a static one - containing four fixed detectors D(sub i) (i = 1 to 4). Section 3 of this paper considers the effect of Earth oblateness on AD accuracy for TRMM. This effect ideally will not induce AD errors on TRMM when data from all four D(sub i) are present. When data from only two or three D(sub i) are available, however, a spherical Earth approximation can introduce errors of 0.05 to 0.30 deg on TRMM. These oblateness-induced errors are eliminated by a new algorithm that uses the results of Section 2 to model the Earth disk as an ellipse.

  19. Earth Science

    NASA Image and Video Library

    1992-07-18

    Workers at Launch Complex 17 Pad A, Kennedy Space Center (KSC) encapsulate the Geomagnetic Tail (GEOTAIL) spacecraft (upper) and attached payload Assist Module-D upper stage (lower) in the protective payload fairing. GEOTAIL project was designed to study the effects of Earth's magnetic field. The solar wind draws the Earth's magnetic field into a long tail on the night side of the Earth and stores energy in the stretched field lines of the magnetotail. During active periods, the tail couples with the near-Earth magnetosphere, sometimes releasing energy stored in the tail and activating auroras in the polar ionosphere. GEOTAIL measures the flow of energy and its transformation in the magnetotail and will help clarify the mechanisms that control the imput, transport, storage, release, and conversion of mass, momentum, and energy in the magnetotail.

  20. The Lifeworld Earth and a Modelled Earth

    ERIC Educational Resources Information Center

    Juuti, Kalle

    2014-01-01

    The goal of this paper is to study the question of whether a phenomenological view of the Earth could be empirically endorsed. The phenomenological way of thinking considers the Earth as a material entity, but not as an object as viewed in science. In the learning science tradition, tracking the process of the conceptual change of the shape of the…

  1. Earth Observation

    NASA Image and Video Library

    2014-06-01

    ISS040-E-006327 (1 June 2014) --- A portion of International Space Station solar array panels and Earth?s horizon are featured in this image photographed by an Expedition 40 crew member on the space station.

  2. The Effects of Earth Science Programs on Student Knowledge and Interest in Earth Science

    NASA Astrophysics Data System (ADS)

    Wilson, A.

    2016-12-01

    Ariana Wilson, Chris Skinner, Chris Poulsen Abstract For many years, academic programs have been in place for the instruction of young students in the earth sciences before they undergo formal training in high school or college. However, there has been little formal assessment of the impacts of these programs on student knowledge of the earth sciences and their interest in continuing with earth science. On August 6th-12th 2016 I will attend the University of Michigan's annual Earth Camp, where I will 1) ascertain high school students' knowledge of earth science-specifically atmospheric structure and wind patterns- before and after Earth Camp, 2) record their opinions about earth science before and after Earth Camp, and 3) record how the students feel about how the camp was run and what could be improved. I will accomplish these things through the use of surveys asking the students questions about these subjects. I expect my results will show that earth science programs like Earth Camp deepen students' knowledge of and interest in earth science and encourage them to continue their study of earth science in the future. I hope these results will give guidance on how to conduct future learning programs and how to recruit more students to become earth scientists in the future.

  3. Earth Science Information Center

    USGS Publications Warehouse

    ,

    1991-01-01

    An ESIC? An Earth Science Information Center. Don't spell it. Say it. ESIC. It rhymes with seasick. You can find information in an information center, of course, and you'll find earth science information in an ESIC. That means information about the land that is the Earth, the land that is below the Earth, and in some instances, the space surrounding the Earth. The U.S. Geological Survey (USGS) operates a network of Earth Science Information Centers that sell earth science products and data. There are more than 75 ESIC's. Some are operated by the USGS, but most are in other State or Federal agencies. Each ESIC responds to requests for information received by telephone, letter, or personal visit. Your personal visit.

  4. Earth meandering

    NASA Astrophysics Data System (ADS)

    Asadiyan, H.; Zamani, A.

    2009-04-01

    In this paper we try to put away current Global Tectonic Model to look the tectonic evolution of the earth from new point of view. Our new dynamic model is based on study of river meandering (RM) which infer new concept as Earth meandering(EM). In a universal gravitational field if we consider a clockwise spiral galaxy model rotate above Ninety East Ridge (geotectonic axis GA), this system with applying torsion field (likes geomagnetic field) in side direction from Rocky Mt. (west geotectonic pole WGP) to Tibetan plateau TP (east geotectonic pole EGP),it seems that pulled mass from WGP and pushed it in EGP due to it's rolling dynamics. According to this idea we see in topographic map that North America and Green land like a tongue pulled from Pacific mouth toward TP. Actually this system rolled or meander the earth over itself fractaly from small scale to big scale and what we see in the river meandering and Earth meandering are two faces of one coin. River transport water and sediments from high elevation to lower elevation and also in EM, mass transport from high altitude-Rocky Mt. to lower altitude Himalaya Mt. along 'S' shape geodetic line-optimum path which connect points from high altitude to lower altitude as kind of Euler Elastica(EE). These curves are responsible for mass spreading (source) and mass concentration (sink). In this regard, tiltness of earth spin axis plays an important role, 'S' are part of sigmoidal shape which formed due to intersection of Earth rolling with the Earth glob and actual feature of transform fault and river meandering. Longitudinal profile in mature rivers as a part of 'S' curve also is a kind of EE. 'S' which bound the whole earth is named S-1(S order 1) and cube corresponding to this which represent Earth fracturing in global scale named C-1(cube order 1 or side vergence cube SVC), C-1 is a biggest cycle of spiral polygon, so it is not completely closed and it has separation about diameter of C-7. Inside SVC we introduce cone

  5. Defending Planet Earth: Near-Earth Object Surveys and Hazard Mitigation Strategies

    NASA Technical Reports Server (NTRS)

    2010-01-01

    The United States spends approximately four million dollars each year searching for near-Earth objects (NEOs). The objective is to detect those that may collide with Earth. The majority of this funding supports the operation of several observatories that scan the sky searching for NEOs. This, however, is insufficient in detecting the majority of NEOs that may present a tangible threat to humanity. A significantly smaller amount of funding supports ways to protect the Earth from such a potential collision or "mitigation." In 2005, a Congressional mandate called for NASA to detect 90 percent of NEOs with diameters of 140 meters of greater by 2020. Defending Planet Earth: Near-Earth Object Surveys and Hazard Mitigation Strategies identifies the need for detection of objects as small as 30 to 50 meters as these can be highly destructive. The book explores four main types of mitigation including civil defense, "slow push" or "pull" methods, kinetic impactors and nuclear explosions. It also asserts that responding effectively to hazards posed by NEOs requires national and international cooperation. Defending Planet Earth: Near-Earth Object Surveys and Hazard Mitigation Strategies is a useful guide for scientists, astronomers, policy makers and engineers.

  6. Discover Earth: Earth's Energy Budget or Can You Spare a Sun?

    NASA Technical Reports Server (NTRS)

    Gates, Tom; Peters, Dale E.; Steeley, Jeanne

    1999-01-01

    Discover Earth is a NASA-sponsored project for teachers of grades 5-12, designed to: enhance understanding of the Earth as an integrated system enhance the interdisciplinary approach to science instruction, and provide classroom materials that focus on those goals. Discover Earth is conducted by the Institute for Global Environmental Strategies in collaboration with Dr. Eric Barron, Director, Earth System Science Center, The Pennsylvania State University; and Dr. Robert Hudson, Chair, the Department of Meteorology, University of Maryland at College Park.

  7. Earth - South America First Frame of Earth Spin Movie

    NASA Image and Video Library

    1996-01-29

    This color image of the Earth was obtained by NASA's Galileo at about 6:10 a.m. Pacific Standard Time on Dec. 11, 1990, when the spacecraft was about 1.3 million miles from the planet during the first of two Earth flybys on its way to Jupiter. The color composite used images taken through the red, green and violet filters. South America is near the center of the picture, and the white, sunlit continent of Antarctica is below. Picturesque weather fronts are visible in the South Atlantic, lower right. This is the first frame of the Galileo Earth spin movie, a 500- frame time-lapse motion picture showing a 25-hour period of Earth's rotation and atmospheric dynamics. A movie is availalble at http://photojournal.jpl.nasa.gov/catalog/PIA00114

  8. Simulation of interference between Earth stations and Earth-orbiting satellites

    NASA Technical Reports Server (NTRS)

    Bishop, D. F.

    1994-01-01

    It is often desirable to determine the potential for radio frequency interference between earth stations and orbiting spacecraft. This information can be used to select frequencies for radio systems to avoid interference or it can be used to determine if coordination between radio systems is necessary. A model is developed that will determine the statistics of interference between earth stations and elliptical orbiting spacecraft. The model uses orbital dynamics, detailed antenna patterns, and spectral characteristics to obtain accurate levels of interference at the victim receiver. The model is programmed into a computer simulation to obtain long-term statistics of interference. Two specific examples are shown to demonstrate the model. The first example is a simulation of interference from a fixed-satellite earth station to an orbiting scatterometer receiver. The second example is a simulation of interference from earth-exploration satellites to a deep-space earth station.

  9. The Not-So-Rare Earths.

    ERIC Educational Resources Information Center

    Muecke, Gunter K.; Moller, Peter

    1988-01-01

    Describes the characteristics of rare earth elements. Details the physical chemistry of rare earths. Reviews the history of rare earth chemistry and mineralogy. Discusses the mineralogy and crystallography of the formation of rare earth laden minerals found in the earth's crust. Characterizes the geologic history of rare earth elements. (CW)

  10. Sun-Earth Day: Exposing the Public to Sun-Earth Connection Science

    NASA Astrophysics Data System (ADS)

    Thieman, J. R.; Lewis, E.; Cline, T.

    2001-12-01

    The year 2001 marked the first observance of Sun-Earth Day as an event to celebrate the strong interconnection of the life we have on Earth and the dependence of it on the dynamic influence of the Sun. The science of the Sun-Earth Connection has grown dramatically with new satellite and ground-based studies of the Sun and the Sun's extended "atmosphere" in which we live. Space weather is becoming a more common concept that people know can affect their lives. An understanding of the importance of the Sun's dynamic behavior and how this shapes the solar system and especially the Earth is the aim of Sun-Earth Day. The first Sun-Earth event actually took place over two days, April 27 and 28, 2001, in order to accommodate all the events which were planned both in the classroom on Friday the 27th and in more informal settings on Saturday the 28th. The Sun-Earth Connection Education Forum (SECEF) organized the creation of ten thousand packets of educational materials about Sun-Earth Day and distributed them mostly to teachers who were trained to use them in the classroom. Many packets, however, went to science centers, museums, and planetariums as resource materials for programs associated with Sun-Earth Day. Over a hundred scientists used the event as an opportunity to communicate their love of science to audiences in these informal settings. Sun-Earth Day was also greatly assisted by the Amateur Astronomical Society which used the event as a theme for their annual promotion of astronomy in programs given around the country. The Solar and Heliospheric Observatory (SOHO), a satellite mission jointly sponsored by NASA and the European Space Agency (ESA), used Sun-Earth Day in conjunction with the fifth anniversary celebration of SOHO as a basis for many programs and events, especially a large number of happenings in Europe. These included observing parties, art exhibits, demonstrations, etc. Examples of some of the innovative ways that Sun-Earth Day was brought into people

  11. Early Earth(s) Across Time and Space

    NASA Astrophysics Data System (ADS)

    Mojzsis, S.

    2014-04-01

    The geochemical and cosmochemical record of our solar system is the baseline for exploring the question: "when could life appear on a world similar to our own?" Data arising from direct analysis of the oldest terrestrial rocks and minerals from the first 500 Myr of Earth history - termed the Hadean Eon - inform us about the timing for the establishment of a habitable silicate world. Liquid water is the key medium for life. The origin of water, and its interaction with the crust as revealed in the geologic record, guides our exploration for a cosmochemically Earth-like planets. From the time of primary planetary accretion to the start of the continuous rock record on Earth at ca. 3850 million years ago, our planet experienced a waning bolide flux that partially or entirely wiped out surface rocks, vaporized oceans, and created transient serpentinizing atmospheres. Arguably, "Early Earths" across the galaxy may start off as ice planets due to feeble insolation from their young stars, occasionally punctuated by steam atmospheres generated by cataclysmic impacts. Alternatively, early global environments conducive to life spanned from a benign surface zone to deep into crustal rocks and sediments. In some scenarios, nascent biospheres benefit from the exogenous delivery of essential bio-elements via leftovers of accretion, and the subsequent establishment of planetary-scale hydrothermal systems. If what is now known about the early dynamical regime of the Earth serves as any measure of the potential habitability of worlds across space and time, several key boundary conditions emerge. These are: (i) availability and long-term stability of liquid water; (ii) presence of energy resources; (iii) accessibility of organic raw materials; (iv) adequate inventory of radioisotopes to drive internal heating; (v) gross compositional parameters such as mantle/core mass ratio, and (vi) P-T conditions at or near the surface suitable for sustaining biological activity. Life could

  12. L’évaluation et la prise en charge des enfants et des adolescents victimes d’une commotion liée à un sport

    PubMed Central

    Purcell, Laura K

    2012-01-01

    RÉSUMÉ Les commotions sont des blessures sportives fréquentes, et elles sont particulièrement courantes chez les enfants et les adolescents qui participent à des sports organisés ou à des activités récréatives. Les symptômes de commotion peuvent être subtils et négligés par les athlètes, les entraîneurs et les parents. Un enfant ou un adolescent qui est victime d’une commotion devrait être immédiatement retiré du jeu et être évalué par un médecin dans les plus brefs délais. Il devrait éviter les activités physiques et cognitives pour se remettre de la commotion. Une fois les symptômes complètement résorbés au repos, l’athlète peut suivre un protocole d’effort graduel, supervisé par un médecin, avant d’obtenir l’autorisation médicale de retourner au jeu. Il est essentiel que tous ceux qui participent aux activités sportives pour les enfants et les adolescents connaissent les signes et symptômes de commotion afin qu’on puisse poser un diagnostic exact et rapide et amorcer une évaluation et une prise en charge convenables. Le présent document de principes remplace celui qui a été publié en 2006.

  13. NASA Earth Day 2014

    NASA Image and Video Library

    2014-04-22

    NASA Administrator Charles Bolden speaks to students who attended the NASA sponsored Earth Day event April 22, 2014 at Union Station in Washington, DC. NASA sponsored the Earth Day event as part of its "Earth Right Now" campaign, celebrating the launch of five Earth-observing missions in 2014. Photo Credit: (NASA/Aubrey Gemignani)

  14. Un gars, une fille: plaidoyer pour la culture avec un "petit c" dans un cours de francais languae etrangere (Un gars, une fille: Culture with a "Litte c" in a French as a econd Language Course).

    ERIC Educational Resources Information Center

    Black, Catherine

    2001-01-01

    Looks at the Quebecois TV show, "Un gars, Une fille" used in a university French course to teach the socio-cultural reality that underlies all linguistic utterances in a university-level French course. Attempts to identify what makes the show more authentic than videos and CD ROMs that accompany most language textbooks in French.…

  15. Discover Earth

    NASA Technical Reports Server (NTRS)

    1997-01-01

    Discover Earth is a NASA-funded project for teachers of grades 5-12 who want to expand their knowledge of the Earth system, and prepare to become master teachers who promote Earth system science in their own schools, counties, and throughout their state. Participants from the following states are invited to apply: Connecticut, Delaware, Maine, Maryland, Massachusetts, New Hampshire, New Jersey, New York, Pennsylvania, Rhode Island, Vermont, and Washington, DC. Teachers selected for the project participate in a two-week summer workshop conducted at the University of Maryland, College Park; develop classroom-ready materials during the workshop for broad dissemination; conduct a minimum of two peer training activities during the coming school year; and participate in other enrichment/education opportunities as available and desired. Discover Earth is a team effort that utilizes expertise from a range of contributors, and balances science content with hands-on classroom applications.

  16. La haute fiabilité en soins de santé: la création d'une culture et d'une mentalité favorisant la sécurité des patients.

    PubMed

    Cochrane, Bonnie S; Hagins, Mitch; Picciano, Gino; King, John A; Marshall, David A; Nelson, Brian; Deao, Craig

    2017-03-01

    Les préjudices que subissent les patients recevant des soins de santé représentent un fardeau considérable et peuvent avoir de graves répercussions sur les patients et les familles ainsi que sur la capacité des systèmes de santé de gérer l'accès des patients, leurs déplacements dans le système et les temps d'attente. L'intérêt pour la science de la haute fiabilité, mise au point à l'origine dans des secteurs comme l'aviation commerciale, qui ont un bilan exceptionnel en matière de sécurité, est une nouvelle tendance en soins de santé qui pourrait aider les organisations et les systèmes à atteindre le but ultime : zéro préjudice subi par les patients. Cet article fait valoir que zéro préjudice au patient est un impératif fondamental et que la science de la haute fiabilité peut aider à accélérer et à soutenir les progrès vers ce but vital. Bien que les pratiques utilisées dans d'autres secteurs ne soient pas facilement transférables aux soins de santé et qu'il n'existe pas encore un seul modèle éprouvé pour les organisations à haute fiabilité en santé, des organisations de premier plan commencent à faire la démonstration de stratégies efficaces propres aux soins de santé. L'expérience du réseau international d'organisations partenaires du groupe Studer est utilisée pour illustrer et comprendre ces premiers efforts. Le cadre Evidence-Based Leadership SM (leadership fondé sur les données probantes) du groupe Studer est appliqué dans différents milieux de soins de santé pour transformer la culture et la gestion du changement visant à favoriser une haute fiabilité. Il propose une démarche et des ressources pour progresser vers le but zéro préjudice subi par les patients et tous les avantages liés à l'utilisation efficiente de nos précieuses ressources en soins de santé.

  17. Uderstanding Snowball Earth Deglaciation

    NASA Astrophysics Data System (ADS)

    Abbot, D. S.

    2012-12-01

    Earth, a normally clement planet comfortably in its star's habitable zone, suffered global or nearly global glaciation at least twice during the Neoproterozoic era (at about 635 and 710 million years ago). Viewed in the context of planetary evolution, these pan-global glaciations (Snowball Earth events) were extremely rapid, lasting only a few million years. The dramatic effect of the Snowball Earth events on the development of the planet can be seen through their link to rises in atmospheric oxygen and evolutionary innovations. These potential catastrophes on an otherwise clement planet can be used to gain insight into planetary habitability more generally. Since Earth is not currently a Snowball, a sound deglaciation mechanism is crucial for the viability of the Snowball Earth hypothesis. The traditional deglaciation mechanism is a massive build up of CO2 due to reduced weathering during Snowball Earth events until tropical surface temperatures reach the melting point. Once initiated, such a deglaciation might happen on a timescale of only dozens of thousands of years and would thrust Earth from the coldest climate in its history to the warmest. Therefore embedded in Snowball Earth events is an even more rapid and dramatic environmental change. Early global climate model simulations raised doubt about whether Snowball Earth deglaciation could be achieved at a CO2 concentration low enough to be consistent with geochemical data, which represented a potential challenge to the Snowball Earth hypothesis. Over the past few years dust and clouds have emerged as the essential missing additional processes that would allow Snowball Earth deglaciation at a low enough CO2 concentration. I will discuss the dust and cloud mechanisms and the modeling behind these ideas. This effort is critical for the broader implications of Snowball Earth events because understanding the specific deglaciation mechanism determines whether similar processes could happen on other planets.

  18. The "Earth Physics" Workshops Offered by the Earth Science Education Unit

    ERIC Educational Resources Information Center

    Davies, Stephen

    2012-01-01

    Earth science has a part to play in broadening students' learning experience in physics. The Earth Science Education Unit presents a range of (free) workshops to teachers and trainee teachers, suggesting how Earth-based science activities, which show how we understand and use the planet we live on, can easily be slotted into normal science…

  19. An Algorithm for Converting Static Earth Sensor Measurements into Earth Observation Vectors

    NASA Technical Reports Server (NTRS)

    Harman, R.; Hashmall, Joseph A.; Sedlak, Joseph

    2004-01-01

    An algorithm has been developed that converts penetration angles reported by Static Earth Sensors (SESs) into Earth observation vectors. This algorithm allows compensation for variation in the horizon height including that caused by Earth oblateness. It also allows pitch and roll to be computed using any number (greater than 1) of simultaneous sensor penetration angles simplifying processing during periods of Sun and Moon interference. The algorithm computes body frame unit vectors through each SES cluster. It also computes GCI vectors from the spacecraft to the position on the Earth's limb where each cluster detects the Earth's limb. These body frame vectors are used as sensor observation vectors and the GCI vectors are used as reference vectors in an attitude solution. The attitude, with the unobservable yaw discarded, is iteratively refined to provide the Earth observation vector solution.

  20. Trajet de soins des personnes âgées à Bobo-Dioulasso, au Burkina Faso: une enquête transversale

    PubMed Central

    Hien, Hervé; Berthé, Abdramane; Konaté, Blahima; Drabo, Maxime koiné; Tou, Fatoumata; Somda, Désiré; Badini-Kinda, Fatoumata; Macq, Jean

    2015-01-01

    Introduction En Afrique, il y n'a pas encore une maitrise du trajet de soins des personnes âgées pour construire des modèles de soins adaptés afin d'améliorer leur prise en charge. L'objectif de cette étude était de décrire le trajet de soins des personnes âgées à Bobo-Dioulasso. Méthodes Nous avons réalisé une étude transversale à prédominance qualitative avec des personnes âgées vivant dans les ménages dans la ville de Bobo-Dioulasso de septembre à novembre 2012. Nous avons sélectionné 30 personnes âgées de manière raisonnée dans 22 secteurs. Des entretiens qualitatifs ont été réalisés. Le recours aux soins formels, informels et mixtes a été analysé. Résultats Le trajet de soins des personnes âgées à Bobo-Dioulasso était à prédominance mixte: elles utilisaient à la fois pour le même épisode de maladie les services publics et privés l'automédication à domicile, la médecine traditionnelle, l'utilisation des médicaments du marche informel de la rue. Les premiers recours aux soins étaient à l'initiative des personnes âgées elles-mêmes. Les recours aux soins formels étaient largement utilisés par les personnes âgées qui avaient un revenu de pension. Conclusion Devant la complexité de la prise en charge des personnes âgées présentant plusieurs pathologies et ayant différents recours des soins il y a une nécessité d'orienter le système d'offre de soins vers une coordination dite « collective ». PMID:26097632

  1. Tidal Locking Of The Earth

    NASA Astrophysics Data System (ADS)

    Koohafkan, Michael

    2006-05-01

    The Moon's orbit and spin period are nearly synchronized, or tidally locked. Could the Moon's orbit and the Earth's spin eventually synchronize as well? The Moon's gravitational pull on the Earth produces tides in our oceans, and tidal friction gradually lengthens our days. Less obvious gravitational interactions between the Earth and Moon may also have effects on Earth's spin. The Earth is slightly distorted into an egg-like shape, and the torque exerted by the Moon on our equatorial bulge slowly changes the tilt of our spin axis. How do effects such as these change as the Moon drifts away from Earth? I will examine gravitational interactions between Earth and Moon to learn how they contribute to the deceleration of the Earth's rotation. My goal is to determine the amount of time it would take for the Earth's rotational speed to decelerate until the period of a single rotation matches the period of the Moon's orbit around Earth -- when the Earth is ``tidally locked'' with the Moon. I aim to derive a general mathematical expression for the rotational deceleration of the Earth due to Moon's gravitational influences.

  2. Modeling of the Earth's gravity field using the New Global Earth Model (NEWGEM)

    NASA Technical Reports Server (NTRS)

    Kim, Yeong E.; Braswell, W. Danny

    1989-01-01

    Traditionally, the global gravity field was described by representations based on the spherical harmonics (SH) expansion of the geopotential. The SH expansion coefficients were determined by fitting the Earth's gravity data as measured by many different methods including the use of artificial satellites. As gravity data have accumulated with increasingly better accuracies, more of the higher order SH expansion coefficients were determined. The SH representation is useful for describing the gravity field exterior to the Earth but is theoretically invalid on the Earth's surface and in the Earth's interior. A new global Earth model (NEWGEM) (KIM, 1987 and 1988a) was recently proposed to provide a unified description of the Earth's gravity field inside, on, and outside the Earth's surface using the Earth's mass density profile as deduced from seismic studies, elevation and bathymetric information, and local and global gravity data. Using NEWGEM, it is possible to determine the constraints on the mass distribution of the Earth imposed by gravity, topography, and seismic data. NEWGEM is useful in investigating a variety of geophysical phenomena. It is currently being utilized to develop a geophysical interpretation of Kaula's rule. The zeroth order NEWGEM is being used to numerically integrate spherical harmonic expansion coefficients and simultaneously determine the contribution of each layer in the model to a given coefficient. The numerically determined SH expansion coefficients are also being used to test the validity of SH expansions at the surface of the Earth by comparing the resulting SH expansion gravity model with exact calculations of the gravity at the Earth's surface.

  3. Carcinome épidermoïde de l’urètre masculin révélé par une rupture spontanée de l’urètre

    PubMed Central

    Ghorbel, Jilani; Hafsia, Ghassen; Derouiche, Amine; Jrad, Anis; Chebil, Mohamed

    2011-01-01

    Résumé Le carcinome épidermoïde de l’urètre masculin est une tumeur rare, les tumeurs de l’urètre tous types confondus représentant moins de 1 % des tumeurs de l’appareil urinaire. Le pronostic reste défavorable malgré un traitement chirurgical énergique. La radiochimiothérapie semble être un traitement prometteur, mais son rôle doit être défini par d’autres études. Nous rapportons un cas rare de carcinome épidermoïde de l’urètre bulbo-membraneux découvert à un stade localement avancé après observation d’une rupture urétrale transtumorale chez un homme âgé de 70 ans. Le patient a été traité, après drainage vésical, par une irradiation externe associée à une chimiothérapie par cisplatine, et est décédé après progression de la maladie sur un an. La rupture spontanée de l’urètre transtumorale est un mode de découverte exceptionnel témoignant d’une évolution locale défavorable, ce qui rend ces tumeurs difficilement opérables. Cependant, l’espoir actuel réside dans des protocoles thérapeutiques associant radiothérapie et chimiothérapie. PMID:21672490

  4. Earth Science

    NASA Image and Video Library

    1976-01-01

    The LAGEOS I (Laser Geodynamics Satellite) was developed and launched by the Marshall Space Flight Center on May 4, 1976 from Vandenberg Air Force Base, California . The two-foot diameter satellite orbited the Earth from pole to pole and measured the movements of the Earth's surface.

  5. D'une ouverture de la voyelle /epsilon/ en finale absolue en francais quebecois : analyse acoustique et perceptive

    NASA Astrophysics Data System (ADS)

    Riverin-Coutlee, Josiane

    Cette contribution est consacree a l'ouverture du /epsilon/ en finale absolue, un phenomene phonetique repute etre en declin en francais quebecois et caracteristique de locuteurs âges, peu scolarises, issus de milieux populaires et s'exprimant en situation de communication informelle. Une analyse acoustique de 480 voyelles /epsilon/ issues de la parole formelle de 40 jeunes etudiants universitaires originaires des centres urbains de Saguenay et de Quebec revele toutefois que le phenomene est encore bien vivant en francais quebecois et qu'il est plus frequent chez les locuteurs de Saguenay, une tendance validee auditivement par accord inter-juges. Les resultats d'un test de discrimination et d'identification mene aupres de 26 etudiants universitaires originaires de ces deux memes villes indiquent que les auditeurs naifs de Saguenay semblent moins sensibles a la variation et moins enclins a juger de l'origine geographique d'un locuteur a partir de sa prononciation de la voyelle /epsilon/ en fin de mot.

  6. Raising awareness for research on earth walls, and earth scientific aspects

    NASA Astrophysics Data System (ADS)

    van den Ancker, Hanneke; Jungerius, Pieter Dirk; Baas, Henk; Groenewoudt, Bert; Peen, Charlotte

    2013-04-01

    A conference to raise awareness In the Netherlands, little research on earth walls has been done. To improve attention for earth walls, a number of organisations, including Geoheritage NL, organized a conference at the RCE, the Cultural Heritage Agency of the Netherlands. The conference* presented a state-of-the-art of research done. The book with the presentations, and extra case studies added, was published in December 2012. The book concludes with a research action list, including earth science research, and can be downloaded freely from the internet. It has English summaries. The earth science aspects Historical earth walls do not only add cultural value to a landscape, but also geodiversity value. Apart from geomorphological aspects, the walls contain information about past land- and climate conditions: - They cover up a former topography, a past landscape. A relevant source of scientific information where lands are levelled, as is the case in many parts of The Netherlands; - The soil formation under the earth wall is a reference soil. The soil formation in the top of the wall gives insight in the rate of soil formation in relationship with the age and parent material of the wall; - The soil profiles of different age have ecological significance. Older walls with a more pronounced soil formation often hold forest flora that has disappeared from the surrounding environment, such as historical bush or tree species, autogenetic DNA material or a specific soil fauna; - The materials in the earth walls tell about the process of wall-building. Paleosols and sedimentary structures in the earth walls, in the gullies and colluvial fans along the walls contain information about past land management and climate. - The eroded appearance of the earth walls is part of their history, and contain information about past management and land conditions, has ecological relevance, for example for insects, and is often visually more interesting. Insight in the rates of erosion are

  7. EarthChem: International Collaboration for Solid Earth Geochemistry in Geoinformatics

    NASA Astrophysics Data System (ADS)

    Walker, J. D.; Lehnert, K. A.; Hofmann, A. W.; Sarbas, B.; Carlson, R. W.

    2005-12-01

    The current on-line information systems for igneous rock geochemistry - PetDB, GEOROC, and NAVDAT - convincingly demonstrate the value of rigorous scientific data management of geochemical data for research and education. The next generation of hypothesis formulation and testing can be vastly facilitated by enhancing these electronic resources through integration of available datasets, expansion of data coverage in location, time, and tectonic setting, timely updates with new data, and through intuitive and efficient access and data analysis tools for the broader geosciences community. PetDB, GEOROC, and NAVDAT have therefore formed the EarthChem consortium (www.earthchem.org) as a international collaborative effort to address these needs and serve the larger earth science community by facilitating the compilation, communication, serving, and visualization of geochemical data, and their integration with other geological, geochronological, geophysical, and geodetic information to maximize their scientific application. We report on the status of and future plans for EarthChem activities. EarthChem's development plan includes: (1) expanding the functionality of the web portal to become a `one-stop shop for geochemical data' with search capability across databases, standardized and integrated data output, generally applicable tools for data quality assessment, and data analysis/visualization including plotting methods and an information-rich map interface; and (2) expanding data holdings by generating new datasets as identified and prioritized through community outreach, and facilitating data contributions from the community by offering web-based data submission capability and technical assistance for design, implementation, and population of new databases and their integration with all EarthChem data holdings. Such federated databases and datasets will retain their identity within the EarthChem system. We also plan on working with publishers to ease the assimilation

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

    NASA Astrophysics Data System (ADS)

    Mahjoub, Mehdi

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

  9. Aspects épidémiologiques, pronostiques et thérapeutiques de l'hématome retro placentaire (HRP) dans une maternité de référence en zone rurale

    PubMed Central

    Thiam, Ousmane; Mbaye, Magatte; Diouf, Abdou Aziz; Touré, Fode Baba; Gueye, Mamour; Niang, Mansour; Cissé, Mamadou Lamine; Dièye, Sidy; Moreau, Jean Charles

    2014-01-01

    Introduction IL s'agira ici d’ identifier les particularités diagnostiques et la prise en charge de l'HRP au Centre Hospitalier de Ndioum au Sénégal. Méthodes Etude rétrospective descriptive menée à l'hôpital régional de Ndioum, durant la période allant du 1er Janvier 2009 au 31 Décembre 2011. Toutes les patientes qui avaient présenté un HRP étaient incluses. Pour chaque patiente, nous avions étudié les paramètres socio-démographiques et cliniques, les données thérapeutiques et le pronostic materno-foetal. Résultats La fréquence était de 6,05%. L’âge moyen de nos patientes était compris entre 29 et 84 ans et la parité moyenne de 4,92. Aucune consultation prénatale n’était effectuée chez 16% des patientes. Les évacuations représentaient 66% de cas. L’âge gestationnel moyen était de 36 semaines d'aménorrhées et la majorité des patientes (86%) était en travail. La gravite du tableau clinique était appréciée selon la classification de Sher avec 63% (114 cas) au grade 3. Une coagulopathie était observée chez 27,2% des patientes. Nous avions retrouvé une relation statistiquement significative entre la gravite du tableau clinique et le pronostic maternel (p = 0,026) et foetal (p = 0,0000). Une direction du travail était effectuée chez 109 patientes (60% des cas). L'expulsion foetale était obtenue par voie basse dans 49% des cas et une césarienne était effectuée dans 51% des cas. La morbidité maternelle était dominée par l'anémie secondaire à une hémorragie aigue dans 17,8% des cas et à l'insuffisance rénale aigue dans 6,1% des cas. Les éléments de mauvais pronostic étaient représentés par la gravité du tableau clinique (p = 0,03) et le mode d'admission dominé par les évacuations (p = 0,01), la relation était statistiquement significative. La voie d'accouchement n’était pas retrouvée comme élément de mauvais pronostic (p = 0,09). Nous avions noté douze cas de décès maternels soit 6,6% des

  10. China's rare-earth industry

    USGS Publications Warehouse

    Tse, Pui-Kwan

    2011-01-01

    Introduction China's dominant position as the producer of over 95 percent of the world output of rare-earth minerals and rapid increases in the consumption of rare earths owing to the emergence of new clean-energy and defense-related technologies, combined with China's decisions to restrict exports of rare earths, have resulted in heightened concerns about the future availability of rare earths. As a result, industrial countries such as Japan, the United States, and countries of the European Union face tighter supplies and higher prices for rare earths. This paper briefly reviews China's rare-earth production, consumption, and reserves and the important policies and regulations regarding the production and trade of rare earths, including recently announced export quotas. The 15 lanthanide elements-lanthanum, cerium, praseodymium, neodymium, promethium, samarium, europium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium, and lutetium (atomic numbers 57-71)-were originally known as the rare earths from their occurrence in oxides mixtures. Recently, some researchers have included two other elements-scandium and yttrium-in their discussion of rare earths. Yttrium (atomic number 39), which lies above lanthanum in transition group III of the periodic table and has a similar 3+ ion with a noble gas core, has both atomic and ionic radii similar in size to those of terbium and dysprosium and is generally found in nature with lanthanides. Scandium (atomic number 21) has a smaller ionic radius than yttrium and the lanthanides, and its chemical behavior is intermediate between that of aluminum and the lanthanides. It is found in nature with the lanthanides and yttrium. Rare earths are used widely in high-technology and clean-energy products because they impart special properties of magnetism, luminescence, and strength. Rare earths are also used in weapon systems to obtain the same properties.

  11. L'acquisition d'une language seconde: Quelques developpements theoriques recents (Second Language Acquisition: Some Recent Theoretical Developments).

    ERIC Educational Resources Information Center

    Py, Bernard, Ed.

    1994-01-01

    This collection of articles on second language learning includes: "Action, langage et discours. Les fondements d'une psychologie du langage" ("Action, Language, and Discourse. Foundations of a Psychology of Language") (Jean-Paul Bronckart); "Contextes socio-culturels et appropriation des languages secondes: l'apprentissage en milieu social et la…

  12. EarthEd Online: Open Source Online Software to Support Large Courses

    NASA Astrophysics Data System (ADS)

    Prothero, W. A.

    2003-12-01

    The purpose of the EarthEd Online software project is to support a modern instructional pedagogy in a large, college level, earth science course. It is an ongoing development project that has evolved in a large general education oceanography course over the last decade. Primary goals for the oceanography course are to support learners in acquiring a knowledge of science process, an appreciation for the relevance of science to society, and basic content knowledge. In order to support these goals, EarthEd incorporates: a) integrated access to various kinds of real earth data (and links to web-based data browsers), b) online discussions, live chat, with integrated graphics editing, linking, and upload, c) online writing, reviewing, and grading, d) online homework assignments, e) on demand grade calculation, and f) instructor grade entry and progress reports. The software was created using Macromedia Director. It is distributed to students on a CDROM and updates are downloaded and installed automatically. Data browsers for plate tectonics relevant data ("Our Dynamic Planet"), a virtual exploration of the East Pacific Rise, the World Ocean Atlas-98, and a fishing simulation game are integrated with the EarthEd software. The system is modular which allows new capabilities, such as new data browsers, to be added. Student reactions to the software are positive overall. They are especially appreciative of the on demand grade computation capability. The online writing, commenting and grading is particularly effective in managing the large number of papers that get submitted. The TA's grade the papers, but the instructor can provide feedback to them as they grade the papers, and a record is maintained of all comments and rubric item grades. Commenting is made easy by simply "dragging" a selection of pre-defined comments into the student's text. Scoring is supported by an integrated scoring rubric. All assignments, rubrics, etc. are configured in text files that are downloaded

  13. Earth Global Reference Atmospheric Model (Earth-GRAM) GRAM Virtual Meeting

    NASA Technical Reports Server (NTRS)

    White, Patrick

    2017-01-01

    What is Earth-GRAM? Provide monthly mean and standard deviation for any point in atmosphere; Monthly, Geographic, and Altitude Variation. Earth-GRAM is a C++ software package; Currently distributed as Earth-GRAM 2016. Atmospheric variables included: pressure, density, temperature, horizontal and vertical winds, speed of sound, and atmospheric constituents. Used by engineering community because of ability to create dispersions inatmosphere at a rapid runtime; Often embedded in trajectory simulation software. Not a forecast model. Does not readily capture localized atmospheric effects.

  14. EarthServer: Cross-Disciplinary Earth Science Through Data Cube Analytics

    NASA Astrophysics Data System (ADS)

    Baumann, P.; Rossi, A. P.

    2016-12-01

    The unprecedented increase of imagery, in-situ measurements, and simulation data produced by Earth (and Planetary) Science observations missions bears a rich, yet not leveraged potential for getting insights from integrating such diverse datasets and transform scientific questions into actual queries to data, formulated in a standardized way.The intercontinental EarthServer [1] initiative is demonstrating new directions for flexible, scalable Earth Science services based on innovative NoSQL technology. Researchers from Europe, the US and Australia have teamed up to rigorously implement the concept of the datacube. Such a datacube may have spatial and temporal dimensions (such as a satellite image time series) and may unite an unlimited number of scenes. Independently from whatever efficient data structuring a server network may perform internally, users (scientist, planners, decision makers) will always see just a few datacubes they can slice and dice.EarthServer has established client [2] and server technology for such spatio-temporal datacubes. The underlying scalable array engine, rasdaman [3,4], enables direct interaction, including 3-D visualization, common EO data processing, and general analytics. Services exclusively rely on the open OGC "Big Geo Data" standards suite, the Web Coverage Service (WCS). Conversely, EarthServer has shaped and advanced WCS based on the experience gained. The first phase of EarthServer has advanced scalable array database technology into 150+ TB services. Currently, Petabyte datacubes are being built for ad-hoc and cross-disciplinary querying, e.g. using climate, Earth observation and ocean data.We will present the EarthServer approach, its impact on OGC / ISO / INSPIRE standardization, and its platform technology, rasdaman.References: [1] Baumann, et al. (2015) DOI: 10.1080/17538947.2014.1003106 [2] Hogan, P., (2011) NASA World Wind, Proceedings of the 2nd International Conference on Computing for Geospatial Research

  15. Earth Science Education Plan: Inspire the Next Generation of Earth Explorers

    NASA Technical Reports Server (NTRS)

    2004-01-01

    The Education Enterprise Strategy, the expanding knowledge of how people learn, and the community-wide interest in revolutionizing Earth and space science education have guided us in developing this plan for Earth science education. This document builds on the success of the first plan for Earth science education published in 1996; it aligns with the new framework set forth in the NASA Education Enterprise Strategy; it recognizes the new educational opportunities resulting from research programs and flight missions; and it builds on the accomplishments th'at the Earth Science Enterprise has made over the last decade in studying Earth as a system. This document embodies comprehensive, practicable plans for inspiring our children; providing educators with the tools they need to teach science, technology, engineering, and mathematics (STEM); and improving our citizens' scientific literacy. This plan describes an approach to systematically sharing knowledge; developing the most effective mechanisms to achieve tangible, lasting results; and working collaboratively to catalyze action at a scale great enough to ensure impact nationally and internationally. This document will evolve and be periodically reviewed in partnership with the Earth science education community.

  16. Beautiful Earth: Inspiring Native American students in Earth Science through Music, Art and Science

    NASA Astrophysics Data System (ADS)

    Casasanto, V.; Rock, J.; Hallowell, R.; Williams, K.; Angell, D.; Beautiful Earth

    2011-12-01

    The Beautiful Earth program, awarded by NASA's Competitive Opportunities in Education and Public Outreach for Earth and Space Science (EPOESS), is a live multi-media performance at partner science centers linked with hands-on workshops featuring Earth scientists and Native American experts. It aims to inspire, engage and educate diverse students in Earth science through an experience of viewing the Earth from space as one interconnected whole, as seen through the eyes of astronauts. The informal education program is an outgrowth of Kenji Williams' BELLA GAIA Living Atlas Experience (www.bellagaia.com) performed across the globe since 2008 and following the successful Earth Day education events in 2009 and 2010 with NASA's DLN (Digital Learning Network) http://tinyurl.com/2ckg2rh. Beautiful Earth takes a new approach to teaching, by combining live music and data visualizations, Earth Science with indigenous perspectives of the Earth, and hands-on interactive workshops. The program will utilize the emotionally inspiring multi-media show as a springboard to inspire participants to learn more about Earth systems and science. Native Earth Ways (NEW) will be the first module in a series of three "Beautiful Earth" experiences, that will launch the national tour at a presentation in October 2011 at the MOST science museum in collaboration with the Onandaga Nation School in Syracuse, New York. The NEW Module will include Native American experts to explain how they study and conserve the Earth in their own unique ways along with hands-on activities to convey the science which was seen in the show. In this first pilot run of the module, 110 K-12 students with faculty and family members of the Onandaga Nations School will take part. The goal of the program is to introduce Native American students to Earth Sciences and STEM careers, and encourage them to study these sciences and become responsible stewards of the Earth. The second workshop presented to participants will be the

  17. Galileo 1989 VEEGA trajectory design. [Venus-Earth-Earth-Gravity-Assist

    NASA Technical Reports Server (NTRS)

    D'Amario, Louis A.; Byrnes, Dennis V.; Johannesen, Jennie R.; Nolan, Brian G.

    1989-01-01

    The new baseline for the Galileo Mission is a 1989 Venus-earth-earth gravity-assist (VEEGA) trajectory, which utilizes three gravity-assist planetary flybys in order to reduce launch energy requirements significantly compared to other earth-Jupiter transfer modes. The launch period occurs during October-November 1989. The total flight time is about 6 years, with November 1995 as the most likely choice for arrival at Jupiter. Optimal 1989 VEEGA trajectories have been generated for a wide range of earth launch dates and Jupiter arrival dates. Launch/arrival space contour plots are presented for various trajectory parameters, including propellant margin, which is used to measure mission performance. The accessible region of the launch/arrival space is defined by propellant margin and launch energy constraints; the available launch period is approximately 1.5 months long.

  18. Earth Wisdom.

    ERIC Educational Resources Information Center

    Van Matre, Steve

    1985-01-01

    In our human-centered ignorance and arrogance we are rapidly destroying the earth. We must start helping people understand the big picture of ecological concepts. What these concepts mean for our own lives and how we must begin to change our lifestyles in order to live more harmoniously with the earth. (JHZ)

  19. Earth observation images taken as part of the EarthKAM educational program

    NASA Image and Video Library

    2000-02-13

    S99-E-5267 (13 February 2000) --- City of El Paso, Texas, and Ciudad Juarez, Chihuahua, Mexico and the Rio Grande River, which separates them. An electronic still camera (ESC), mounted in one of Endeavour's aft flight deck windows, is recording imagery of hundreds of Earth targets for the EarthKAM project. Students across the United States and in France, Germany and Japan are taking photos throughout the STS-99 mission. And they are using these new photos, plus all the images already available in the EarthKAM system, to enhance their classroom learning in Earth and space science, social studies, geography, mathematics and more. For general EarthKAM information and more images from this flight, go to http://www.earthkam.ucsd.edu/

  20. Charge-separated and molecular heterobimetallic rare earth-rare earth and alkaline earth-rare earth aryloxo complexes featuring intramolecular metal-pi-arene interactions.

    PubMed

    Deacon, Glen B; Junk, Peter C; Moxey, Graeme J; Ruhlandt-Senge, Karin; St Prix, Courtney; Zuniga, Maria F

    2009-01-01

    Treatment of a rare earth metal (Ln) and a potential divalent rare earth metal (Ln') or an alkaline earth metal (Ae) with 2,6-diphenylphenol (HOdpp) at elevated temperatures (200-250 degrees C) afforded heterobimetallic aryloxo complexes, which were structurally characterised. A charge-separated species [(Ln'/Ae)(2)(Odpp)(3)][Ln(Odpp)(4)] was obtained for a range of metals, demonstrating the similarities between the chemistry of the divalent rare earth metals and the alkaline earth metals. The [(Ln'/Ae)(2)(Odpp)(3)](+) cation in the heterobimetallic structures is unusual in that it consists solely of bridging aryloxide ligands. A molecular heterobimetallic species [AeEu(Odpp)(4)] (Ae = Ca, Sr, Ba) was obtained by treating an alkaline earth metal and Eu metal with HOdpp at elevated temperatures. Similarly, [BaSr(Odpp)(4)] was prepared by treating Ba metal and Sr metal with HOdpp. Treatment of [Ba(2)(Odpp)(4)] with [Mg(Odpp)(2)(thf)(2)] in toluene afforded [Ba(2)(Odpp)(3)][Mg(Odpp)(3)(thf)]. Analogous solution-based syntheses were not possible for [(Ln'/Ae)(2)(Odpp)(3)][Ln(Odpp)(4)] complexes, for which the free-metal route was essential. As a result of the absence of additional donor ligands, the crystal structures of the heterobimetallic complexes feature extensive pi-Ph-metal interactions involving the pendant phenyl groups of the Odpp ligands, thus enabling the large electropositive metal atoms to attain coordination saturation. The charge-separated heterobimetallic species were purified by extraction with toluene/thf mixtures at ambient temperature (Ba-containing compounds) or by extraction with toluene under pressure above the boiling point of the solvent (other products). In donor solvents, heterobimetallic complexes other than those containing barium were found to fragment into homometallic species.

  1. Towards Big Earth Data Analytics: The EarthServer Approach

    NASA Astrophysics Data System (ADS)

    Baumann, Peter

    2013-04-01

    Big Data in the Earth sciences, the Tera- to Exabyte archives, mostly are made up from coverage data whereby the term "coverage", according to ISO and OGC, is defined as the digital representation of some space-time varying phenomenon. Common examples include 1-D sensor timeseries, 2-D remote sensing imagery, 3D x/y/t image timeseries and x/y/z geology data, and 4-D x/y/z/t atmosphere and ocean data. Analytics on such data requires on-demand processing of sometimes significant complexity, such as getting the Fourier transform of satellite images. As network bandwidth limits prohibit transfer of such Big Data it is indispensable to devise protocols allowing clients to task flexible and fast processing on the server. The EarthServer initiative, funded by EU FP7 eInfrastructures, unites 11 partners from computer and earth sciences to establish Big Earth Data Analytics. One key ingredient is flexibility for users to ask what they want, not impeded and complicated by system internals. The EarthServer answer to this is to use high-level query languages; these have proven tremendously successful on tabular and XML data, and we extend them with a central geo data structure, multi-dimensional arrays. A second key ingredient is scalability. Without any doubt, scalability ultimately can only be achieved through parallelization. In the past, parallelizing code has been done at compile time and usually with manual intervention. The EarthServer approach is to perform a samentic-based dynamic distribution of queries fragments based on networks optimization and further criteria. The EarthServer platform is comprised by rasdaman, an Array DBMS enabling efficient storage and retrieval of any-size, any-type multi-dimensional raster data. In the project, rasdaman is being extended with several functionality and scalability features, including: support for irregular grids and general meshes; in-situ retrieval (evaluation of database queries on existing archive structures, avoiding data

  2. Une modélisation de haut niveau des stratégies d'écriture motrice d'enfants en scolarité primaire : approche bayésienne

    NASA Astrophysics Data System (ADS)

    Zaarour, I.; El-Eter, B.; Leray, P.; Heutte, L.; Labiche, J.; Mellier, D.; Zoaeter, M.

    2005-05-01

    L'objectif de cette étude est de découvrir des stratégies d'écriture motrices des enfants en scolarité primaire en adoptant un modèle graphique probabiliste (réseaux bayésiens). Nous représentons une stratégie d'écriture par une variable cachée et nous construisons ainsi un modèle global hiérarchique pour pouvoir lier les stratégies locales aux stratégies globales et modéliser la dépendance probabiliste entre variables et stratégies. Ce modèle hiérarchique, appris à partir des données réelles, nous a permis de découvrir des stratégies consistantes et robustes. Ces résultats nous a permis de favoriser une modélisation temporelle et dynamique des stratégies d'écriture motrices indépendantes de l'âge scolaire.

  3. Étude des perturbations conduites et rayonnées dans une cellule de commutation

    NASA Astrophysics Data System (ADS)

    Costa, F.; Forest, F.; Puzo, A.; Rojat, G.

    1993-12-01

    The principles used in static conversion and the rise of the performances of the new switching devices contribue to increase the level of electromagnetic noises emitted by electronic converters. We have studied the way how these perturbations are created and coupled through their environment in conducted and radiated mode by a switching cell. This one can work in hard switching, zero current or voltage switching modes. We first outline the general problems of electromagnetic pollution and their metrology in converters. Then we describe the experimental environment. We analyse the mechanisms of generation of parasitic signals in a switching cell related to the electrical constraints and its switching mode. The simulated results, issued of the analytical models obtained, are confronted with the experimental ones. Then we show a method to calculate analytically the E and H near fields. It has been confirmed by experimental results. At last, we present, in a synthetic manner, the main results obtained, relative to the switching mode and the electrical constraints, using a new characterizing method. Theses results will allow the designer to incorporate the electromagnetic considerations in the conception of a converter. Les principes de commutation employés en conversion statique, l'évolution des performances statiques et dynamiques des composants, contribuent à faire des dispositifs de conversion statique de puissants générateurs de perturbations conduites et rayonnées. Nous nous sommes attachés à étudier les mécanismes de génération et de couplage des perturbations, tant en mode conduit que rayonné dans des structures à une seule cellule de commutation et fonctionnant selon les trois principaux modes de commutation : commutation forcée, à zéro de courant (ZCS), et à zéro de tension (ZVS). Après la mise en évidence de la problématique de pollution électromagnétique dans les structures et leur métrologie, nous décrivons l'environnement exp

  4. Earth Science

    NASA Image and Video Library

    1994-09-02

    This image depicts a full view of the Earth, taken by the Geostationary Operational Environment Satellite (GOES-8). The red and green charnels represent visible data, while the blue channel represents inverted 11 micron infrared data. The north and south poles were not actually observed by GOES-8. To produce this image, poles were taken from a GOES-7 image. Owned and operated by the National Oceanic and Atmospheric Administration (NOAA), GOES satellites provide the kind of continuous monitoring necessary for intensive data analysis. They circle the Earth in a geosynchronous orbit, which means they orbit the equatorial plane of the Earth at a speed matching the Earth's rotation. This allows them to hover continuously over one position on the surface. The geosynchronous plane is about 35,800 km (22,300 miles) above the Earth, high enough to allow the satellites a full-disc view of the Earth. Because they stay above a fixed spot on the surface, they provide a constant vigil for the atmospheric triggers for severe weather conditions such as tornadoes, flash floods, hail storms, and hurricanes. When these conditions develop, the GOES satellites are able to monitor storm development and track their movements. NASA manages the design and launch of the spacecraft. NASA launched the first GOES for NOAA in 1975 and followed it with another in 1977. Currently, the United States is operating GOES-8, positioned at 75 west longitude and the equator, and GOES-10, which is positioned at 135 west longitude and the equator. (GOES-9, which malfunctioned in 1998, is being stored in orbit as an emergency backup should either GOES-8 or GOES-10 fail. GOES-11 was launched on May 3, 2000 and GOES-12 on July 23, 2001. Both are being stored in orbit as a fully functioning replacement for GOES-8 or GOES-10 on failure.

  5. NASA Earth Day 2014

    NASA Image and Video Library

    2014-04-22

    NASA Administrator Charles Bolden poses for a quick selfie with students who attended the NASA sponsored Earth Day event April 22, 2014 at Union Station in Washington, DC. NASA announced the "Global Selfie" event as part of its "Earth Right Now" campaign, celebrating the launch of five Earth-observing missions in 2014. All selfies posted to social media with the hashtag "GlobalSelfie" will be included in a mosaic image of Earth. Photo Credit: (NASA/Aubrey Gemignani)

  6. Earth Science Informatics - Overview

    NASA Technical Reports Server (NTRS)

    Ramapriyan, H. K.

    2015-01-01

    Over the last 10-15 years, significant advances have been made in information management, there are an increasing number of individuals entering the field of information management as it applies to Geoscience and Remote Sensing data, and the field of informatics has come to its own. Informatics is the science and technology of applying computers and computational methods to the systematic analysis, management, interchange, and representation of science data, information, and knowledge. Informatics also includes the use of computers and computational methods to support decision making and applications. Earth Science Informatics (ESI, a.k.a. geoinformatics) is the application of informatics in the Earth science domain. ESI is a rapidly developing discipline integrating computer science, information science, and Earth science. Major national and international research and infrastructure projects in ESI have been carried out or are on-going. Notable among these are: the Global Earth Observation System of Systems (GEOSS), the European Commissions INSPIRE, the U.S. NSDI and Geospatial One-Stop, the NASA EOSDIS, and the NSF DataONE, EarthCube and Cyberinfrastructure for Geoinformatics. More than 18 departments and agencies in the U.S. federal government have been active in Earth science informatics. All major space agencies in the world, have been involved in ESI research and application activities. In the United States, the Federation of Earth Science Information Partners (ESIP), whose membership includes nearly 150 organizations (government, academic and commercial) dedicated to managing, delivering and applying Earth science data, has been working on many ESI topics since 1998. The Committee on Earth Observation Satellites (CEOS)s Working Group on Information Systems and Services (WGISS) has been actively coordinating the ESI activities among the space agencies. Remote Sensing; Earth Science Informatics, Data Systems; Data Services; Metadata

  7. ACCESS Earth: Promoting Accessibility to Earth System Science for Students with Disabilities

    NASA Astrophysics Data System (ADS)

    Locke, S. M.; Cohen, L.; Lightbody, N.

    2001-05-01

    ACCESS Earth is an intensive summer institute for high school students with disabilities and their teachers that is designed to encourage students with disabilities to consider careers in earth system science. Participants study earth system science concepts at a Maine coastal estuary, using Geographic Information Systems, remote sensing, and field observations to evaluate the impacts of climate change, sea level rise, and development on coastal systems. Teachers, students, and scientists work together to adapt field and laboratory activities for persons with disabilities, including those with mobility and visual impairments. Other sessions include demonstrations of assistive technology, career discussions, and opportunities for students to meet with successful scientists with disabilities from throughout the U.S. The summer institute is one of several programs in development at the University of Southern Maine to address the problem of underrepresentation of people with disabilities in the earth sciences. Other projects include a mentoring program for high school students, a web-based clearinghouse of resources for teaching earth sciences to students with disabilities, and guidebooks for adaptation of popular published earth system science curricula for disabled learners.

  8. Google Earth and Geo Applications: A Toolset for Viewing Earth's Geospatial Information

    NASA Astrophysics Data System (ADS)

    Tuxen-Bettman, K.

    2016-12-01

    Earth scientists measure and derive fundamental data that can be of broad general interest to the public and policy makers. Yet, one of the challenges that has always faced the Earth science community is how to present their data and findings in an easy-to-use and compelling manner. Google's Geo Tools offer an efficient and dynamic way for scientists, educators, journalists and others to both access data and view or tell stories in a dynamic three-dimensional geospatial context. Google Earth in particular provides a dense canvas of satellite imagery on which can be viewed rich vector and raster datasets using the medium of Keyhole Markup Language (KML). Through KML, Google Earth can combine the analytical capabilities of Earth Engine, collaborative mapping of My Maps, and storytelling of Tour Builder and more to make Google's Geo Applications a coherent suite of tools for exploring our planet.https://earth.google.com/https://earthengine.google.com/https://mymaps.google.com/https://tourbuilder.withgoogle.com/https://www.google.com/streetview/

  9. Influence of slip-surface geometry on earth-flow deformation, Montaguto earth flow, southern Italy

    USGS Publications Warehouse

    Guerriero, L.; Coe, Jeffrey A.; Revellio, P.; Grelle, G.; Pinto, F.; Guadagno, F.

    2016-01-01

    We investigated relations between slip-surface geometry and deformational structures and hydrologic features at the Montaguto earth flow in southern Italy between 1954 and 2010. We used 25 boreholes, 15 static cone-penetration tests, and 22 shallow-seismic profiles to define the geometry of basal- and lateral-slip surfaces; and 9 multitemporal maps to quantify the spatial and temporal distribution of normal faults, thrust faults, back-tilted surfaces, strike-slip faults, flank ridges, folds, ponds, and springs. We infer that the slip surface is a repeating series of steeply sloping surfaces (risers) and gently sloping surfaces (treads). Stretching of earth-flow material created normal faults at risers, and shortening of earth-flow material created thrust faults, back-tilted surfaces, and ponds at treads. Individual pairs of risers and treads formed quasi-discrete kinematic zones within the earth flow that operated in unison to transmit pulses of sediment along the length of the flow. The locations of strike-slip faults, flank ridges, and folds were not controlled by basal-slip surface topography but were instead dependent on earth-flow volume and lateral changes in the direction of the earth-flow travel path. The earth-flow travel path was strongly influenced by inactive earth-flow deposits and pre-earth-flow drainages whose positions were determined by tectonic structures. The implications of our results that may be applicable to other earth flows are that structures with strikes normal to the direction of earth-flow motion (e.g., normal faults and thrust faults) can be used as a guide to the geometry of basal-slip surfaces, but that depths to the slip surface (i.e., the thickness of an earth flow) will vary as sediment pulses are transmitted through a flow.

  10. Earth - Moon Conjunction

    NASA Technical Reports Server (NTRS)

    1992-01-01

    On December 16, 1992, 8 days after its encounter with Earth, the Galileo spacecraft looked back from a distance of about 6.2 million kilometers (3.9 million miles) to capture this remarkable view of the Moon in orbit about Earth. The composite photograph was constructed from images taken through visible (violet, red) and near-infrared (1.0-micron) filters. The Moon is in the foreground; its orbital path is from left to right. Brightly colored Earth contrasts strongly with the Moon, which reacts only about one-third as much sunlight as our world. To improve the visibility of both bodies, contrast and color have been computer enhanced. At the bottom of Earth's disk, Antarctica is visible through clouds. The Moon's far side can also be seen. The shadowy indentation in the Moon's dawn terminator--the boundary between its dark and lit sides--is the South Pole-Aitken Basin, one of the largest and oldest lunar impact features. This feature was studied extensively by Galileo during the first Earth flyby in December 1990.

  11. NASA Sun Earth

    NASA Image and Video Library

    2017-12-08

    CME blast and subsequent impact at Earth -- This illustration shows a CME blasting off the Sun’s surface in the direction of Ea CME blast and subsequent impact at Earth -- This illustration shows a CME blasting off the Sun’s surface in the direction of Earth. This left portion is composed of an EIT 304 image superimposed on a LASCO C2 coronagraph. Two to four days later, the CME cloud is shown striking and beginning to be mostly deflected around the Earth’s magnetosphere. The blue paths emanating from the Earth’s poles represent some of its magnetic field lines. The magnetic cloud of plasma can extend to 30 million miles wide by the time it reaches earth. These storms, which occur frequently, can disrupt communications and navigational equipment, damage satellites, and even cause blackouts. (Objects in the illustration are not drawn to scale.) Credit: NASA/GSFC/SOHO/ESA To learn more go to the SOHO website: sohowww.nascom.nasa.gov/home.html To learn more about NASA's Sun Earth Day go here: sunearthday.nasa.gov/2010/index.php

  12. Émission spontanée amplifiée (ÉSA) dans une structure à double cavité verticale (Bi-VCSEL)

    NASA Astrophysics Data System (ADS)

    Boucher, Y.; Gayraud, L.

    2004-11-01

    Nous présentons une étude théorique de l'Émission Spontanée Amplifiée dans une structure verticale à double cavité, décrite en termes de couplage d'ondes. Chaque cavité y est représentée par un saut de phase, tandis que les puits quantiques sont assimilés à des singularités de Dirac de la permittivité. Les sources sont prises en compte dans le cadre du formalisme des matrices de transfert étendues (3 × 3), qui inclut la saturation des zones actives sous l'effet du champ interne. Dans le plan spectral, celui-ci apparaît, au même titre que le champ émis, filtré par la fonction de transfert bimode de la structure.

  13. NASA Earth Day 2014

    NASA Image and Video Library

    2014-04-22

    NASA Astronaut John Mace Grunsfeld takes a quick selfie with astronauts at the International Space Station at the NASA sponsored Earth Day event April 22, 2014 at Union Station in Washington, DC. NASA announced the "Global Selfie" event as part of its "Earth Right Now" campaign, celebrating the launch of five Earth-observing missions in 2014. All selfies posted to social media with the hashtag "GlobalSelfie" will be included in a mosaic image of Earth. Photo Credit: (NASA/Aubrey Gemignani)

  14. Curiosity Mars Rover First Image of Earth and Earth Moon

    NASA Image and Video Library

    2014-02-06

    The two bodies in this portion of an evening-sky view by NASA Mars rover Curiosity are Earth and Earth moon. The rover Mast Camera Mastcam imaged them in the twilight sky of Curiosity 529th Martian day, or sol Jan. 31, 2014.

  15. Earthing: health implications of reconnecting the human body to the Earth's surface electrons.

    PubMed

    Chevalier, Gaétan; Sinatra, Stephen T; Oschman, James L; Sokal, Karol; Sokal, Pawel

    2012-01-01

    Environmental medicine generally addresses environmental factors with a negative impact on human health. However, emerging scientific research has revealed a surprisingly positive and overlooked environmental factor on health: direct physical contact with the vast supply of electrons on the surface of the Earth. Modern lifestyle separates humans from such contact. The research suggests that this disconnect may be a major contributor to physiological dysfunction and unwellness. Reconnection with the Earth's electrons has been found to promote intriguing physiological changes and subjective reports of well-being. Earthing (or grounding) refers to the discovery of benefits-including better sleep and reduced pain-from walking barefoot outside or sitting, working, or sleeping indoors connected to conductive systems that transfer the Earth's electrons from the ground into the body. This paper reviews the earthing research and the potential of earthing as a simple and easily accessed global modality of significant clinical importance.

  16. Earthing: Health Implications of Reconnecting the Human Body to the Earth's Surface Electrons

    PubMed Central

    Chevalier, Gaétan; Sinatra, Stephen T.; Oschman, James L.; Sokal, Karol; Sokal, Pawel

    2012-01-01

    Environmental medicine generally addresses environmental factors with a negative impact on human health. However, emerging scientific research has revealed a surprisingly positive and overlooked environmental factor on health: direct physical contact with the vast supply of electrons on the surface of the Earth. Modern lifestyle separates humans from such contact. The research suggests that this disconnect may be a major contributor to physiological dysfunction and unwellness. Reconnection with the Earth's electrons has been found to promote intriguing physiological changes and subjective reports of well-being. Earthing (or grounding) refers to the discovery of benefits—including better sleep and reduced pain—from walking barefoot outside or sitting, working, or sleeping indoors connected to conductive systems that transfer the Earth's electrons from the ground into the body. This paper reviews the earthing research and the potential of earthing as a simple and easily accessed global modality of significant clinical importance. PMID:22291721

  17. Next-generation Digital Earth

    PubMed Central

    Goodchild, Michael F.; Guo, Huadong; Annoni, Alessandro; Bian, Ling; de Bie, Kees; Campbell, Frederick; Craglia, Max; Ehlers, Manfred; van Genderen, John; Jackson, Davina; Lewis, Anthony J.; Pesaresi, Martino; Remetey-Fülöpp, Gábor; Simpson, Richard; Skidmore, Andrew; Wang, Changlin; Woodgate, Peter

    2012-01-01

    A speech of then-Vice President Al Gore in 1998 created a vision for a Digital Earth, and played a role in stimulating the development of a first generation of virtual globes, typified by Google Earth, that achieved many but not all the elements of this vision. The technical achievements of Google Earth, and the functionality of this first generation of virtual globes, are reviewed against the Gore vision. Meanwhile, developments in technology continue, the era of “big data” has arrived, the general public is more and more engaged with technology through citizen science and crowd-sourcing, and advances have been made in our scientific understanding of the Earth system. However, although Google Earth stimulated progress in communicating the results of science, there continue to be substantial barriers in the public’s access to science. All these factors prompt a reexamination of the initial vision of Digital Earth, and a discussion of the major elements that should be part of a next generation. PMID:22723346

  18. People and the Earth

    NASA Astrophysics Data System (ADS)

    Rogers, John James William; Feiss, P. Geoffrey

    1998-03-01

    People and the Earth examines the numerous ways in which this planet enhances and limits our lifestyles. Written with wit and remarkable insight, and illustrated with numerous case histories, it provides a balanced view of the complex environmental issues facing our civilization. The authors look at the geologic restrictions on our ability to withdraw resources--food, water, energy, and minerals--from the earth, the effect human activity has on the earth, and the lingering damage caused by natural disasters. People and the Earth examines the basic components of our interaction with this planet, provides a lucid, scientific discussion of each issue, and speculates on what the future may hold. It provides the fundamental concepts that will enable us to make wise and conscientious choices on how to live our day-to-day lives. People and the Earth is an ideal introductory textbook and will also appeal to anyone concerned with our evolving relationship to the earth.

  19. Next-generation Digital Earth.

    PubMed

    Goodchild, Michael F; Guo, Huadong; Annoni, Alessandro; Bian, Ling; de Bie, Kees; Campbell, Frederick; Craglia, Max; Ehlers, Manfred; van Genderen, John; Jackson, Davina; Lewis, Anthony J; Pesaresi, Martino; Remetey-Fülöpp, Gábor; Simpson, Richard; Skidmore, Andrew; Wang, Changlin; Woodgate, Peter

    2012-07-10

    A speech of then-Vice President Al Gore in 1998 created a vision for a Digital Earth, and played a role in stimulating the development of a first generation of virtual globes, typified by Google Earth, that achieved many but not all the elements of this vision. The technical achievements of Google Earth, and the functionality of this first generation of virtual globes, are reviewed against the Gore vision. Meanwhile, developments in technology continue, the era of "big data" has arrived, the general public is more and more engaged with technology through citizen science and crowd-sourcing, and advances have been made in our scientific understanding of the Earth system. However, although Google Earth stimulated progress in communicating the results of science, there continue to be substantial barriers in the public's access to science. All these factors prompt a reexamination of the initial vision of Digital Earth, and a discussion of the major elements that should be part of a next generation.

  20. Galileo's Earth-Moon portrait

    NASA Astrophysics Data System (ADS)

    Simarski, Lynn Teo

    Research reported at an AGU session on Galileo's Earth/Moon flyby refined the spacecraft's distinctive portrait of the Earth-Moon system. The Galileo team presented dramatic new views of the Earth and Moon taken last December. Andrew P. Ingersoll showed a color movie of the rotating Earth, made through spectral filters with which Galileo viewed the Earth almost continuously for 25 hours.Galileo also made finely tuned observations of vegetation and clouds, using three very closely spaced spectral wavelengths in the near-infrared, explained W. Reid Thompson. In the resulting images, Argentinian grassland and Brazilian rain forest are clearly distinguished, demonstrating the applicability of this technique for routine monitoring of deforestation, shifts in vegetation due to climate, and other phenomena. Thompson suggested that this capability could be used on the Earth Observing System. One of the spectral bands may also have potential for monitoring cloud condensation, as it appears to differentiate actively condensing, vapor-heavy clouds from higher and drier clouds.

  1. Earth impedance model for through-the-earth communication applications with electrodes

    NASA Astrophysics Data System (ADS)

    Bataller, Vanessa; MuñOz, Antonio; Gaudó, Pilar Molina; Mediano, Arturo; Cuchí, José A.; Villarroel, José L.

    2010-12-01

    Through-the-earth (TTE) communications are relevant in applications such as caving, tunnel and cave rescue, mining, and subsurface radiolocation. The majority of the TTE communication systems use ground electrodes as load antenna. Wires, electrode contact, and earth impedances are the major contributors to the impedance observed by the transmitter. In this paper, state-of-art models found in the literature are reviewed, and an improved method to measure the earth impedance is presented. The paper also proposes an optimal circuit model for earth impedance between electrodes as a function of frequency, as a consequence of the particular conditions of the application. The model is validated with measurements for different soil conditions, showing a good agreement between empirical data and the simulation results.

  2. Earth observing satellite: Understanding the Earth as a system

    NASA Technical Reports Server (NTRS)

    Soffen, Gerald

    1990-01-01

    There is now a plan for global studies which include two very large efforts. One is the International Geosphere/Biosphere Program (IGBP) sponsored by the International Council of Scientific Unions. The other initiative is Mission to Planet Earth, an unbrella program for doing three kinds of space missions. The major one is the Earth Observation Satellite (EOS). EOS is large polar orbiting satellites with heavy payloads. Two will be placed in orbit by NASA, one by the Japanese and one or two by ESA. The overall mission measurement objectives of EOS are summarized: (1) the global distribution of energy input to and energy output from the Earth; (2) the structure, state variables, composition, and dynamics of the atmosphere from the ground to the mesopause; (3) the physical and biological structure, state, composition, and dynamics of the land surface, including terrestrial and inland water ecosystems; (4) the rates, important sources and sinks, and key components and processes of the Earth's biogeochemical cycles; (5) the circulation, surface temperature, wind stress, sea state, and the biological activity of the oceans; (6) the extent, type, state, elevation, roughness, and dynamics of glaciers, ice sheets, snow and sea ice, and the liquid equivalent of snow in the global cryosphere; (7) the global rates, amounts, and distribution of precipitation; and (8) the dynamic motions of the Earth (geophysics) as a whole, including both rotational dynamics and the kinematic motions of the tectonic plates.

  3. Earth Science Informatics - Overview

    NASA Technical Reports Server (NTRS)

    Ramapriyan, H. K.

    2017-01-01

    Over the last 10-15 years, significant advances have been made in information management, there are an increasing number of individuals entering the field of information management as it applies to Geoscience and Remote Sensing data, and the field of informatics has come to its own. Informatics is the science and technology of applying computers and computational methods to the systematic analysis, management, interchange, and representation of science data, information, and knowledge. Informatics also includes the use of computers and computational methods to support decision making and applications. Earth Science Informatics (ESI, a.k.a. geoinformatics) is the application of informatics in the Earth science domain. ESI is a rapidly developing discipline integrating computer science, information science, and Earth science. Major national and international research and infrastructure projects in ESI have been carried out or are on-going. Notable among these are: the Global Earth Observation System of Systems (GEOSS), the European Commissions INSPIRE, the U.S. NSDI and Geospatial One-Stop, the NASA EOSDIS, and the NSF DataONE, EarthCube and Cyberinfrastructure for Geoinformatics. More than 18 departments and agencies in the U.S. federal government have been active in Earth science informatics. All major space agencies in the world, have been involved in ESI research and application activities. In the United States, the Federation of Earth Science Information Partners (ESIP), whose membership includes over 180 organizations (government, academic and commercial) dedicated to managing, delivering and applying Earth science data, has been working on many ESI topics since 1998. The Committee on Earth Observation Satellites (CEOS)s Working Group on Information Systems and Services (WGISS) has been actively coordinating the ESI activities among the space agencies.

  4. The Earth & Moon

    NASA Image and Video Library

    1998-06-04

    During its flight, NASA’s Galileo spacecraft returned images of the Earth and Moon. Separate images of the Earth and Moon were combined to generate this view. http://photojournal.jpl.nasa.gov/catalog/PIA00342

  5. A carbon dioxide radiance model of the earth planet using the conical earth sensor data

    NASA Astrophysics Data System (ADS)

    Deng, Loulou; Mei, Zhiwu; Tu, Zhijun; Yuan, Jun; He, Ting; Wei, Yi

    2013-10-01

    Climate Modeling results show that about 50% of the Earth's outgoing radiation and 75% of the atmospheric outgoing radiation are contained in the far infrared. Generally the earth is considered as a 220~230 K blackbody, and the peak breadth of the Earth's outgoing radiation is around the wavelength of 10 micron. The atmospheric outgoing radiation are contained with five spectral intervals: the water vapor band from 6.33 to 6.85 microns, the ozone band from 8.9 to 10.1microns, the atmospheric window from 10.75 to 11.75 microns, the carbon dioxide band from 14 to 16 microns, and finally the rotational water vapor band from 21 to 125 microns. The properties of the carbon dioxide band is stable than other bands which has been chosen for the work Spectrum of the earth sensors. But the radiation energy of carbon dioxide band is variety and it is a function of latitude, season and weather conditions. Usually the luminance of the Earth's radiation (14 to 16 μm) is from 3 to 7 W/m2Sr. Earth sensor is an important instrument of the Attitude and Orbit Control System (AOCS), and it is sensitive to the curve of the earth's and atmospheric outgoing radiation profile to determine the roll and pitch angles of satellite which are relative to nadir vector. Most earth sensors use profile data gathered form Project Scanner taken in August and December 1966. The earth sensor referred in this paper is the conical scanning earth sensor which is mainly used in the LEO (Low Earth Orbit) satellite. A method to determine the luminance of earth's and atmospheric outgoing radiation (carbon dioxide) using the earth sensor is discussed in this paper. When the conical scanning sensor scan form the space to the earth, a pulse is produced and the pulse breadth is scale with the infrared radiation luminance. Then the infrared radiation luminance can be calculated. A carbon dioxide radiance model of the earth's and atmospheric outgoing radiation is obtained according the luminance data about with

  6. Myopéricardite aiguë simulant un infarctus du myocarde: à propos d'une observation et revue de la littérature

    PubMed Central

    Bouzerda, Abdelmajid

    2015-01-01

    Le diagnostic de myopéricardite aiguë est difficile surtout quand la présentation clinique mime un syndrome coronaire aiguë. Nous rapportons l'observation d'un patient âgé de 40 ans admis pour un syndrome coronarien aiguë ST+ chez qui la coronarographie réalisée en urgence montre un réseau coronaire angio-graphiquement sain. L'imagerie par résonance magnétique (IRM) permettra d'affirmer le diagnostic d'une myopéricardite. Cette observation confirme le rôle primordial de l'IRM cardiaque chez les patients présentant une suspicion clinique de myocardite aiguë ou un tableau de SCA à coronaire saines. PMID:26491513

  7. Melting in super-earths.

    PubMed

    Stixrude, Lars

    2014-04-28

    We examine the possible extent of melting in rock-iron super-earths, focusing on those in the habitable zone. We consider the energetics of accretion and core formation, the timescale of cooling and its dependence on viscosity and partial melting, thermal regulation via the temperature dependence of viscosity, and the melting curves of rock and iron components at the ultra-high pressures characteristic of super-earths. We find that the efficiency of kinetic energy deposition during accretion increases with planetary mass; considering the likely role of giant impacts and core formation, we find that super-earths probably complete their accretionary phase in an entirely molten state. Considerations of thermal regulation lead us to propose model temperature profiles of super-earths that are controlled by silicate melting. We estimate melting curves of iron and rock components up to the extreme pressures characteristic of super-earth interiors based on existing experimental and ab initio results and scaling laws. We construct super-earth thermal models by solving the equations of mass conservation and hydrostatic equilibrium, together with equations of state of rock and iron components. We set the potential temperature at the core-mantle boundary and at the surface to the local silicate melting temperature. We find that ancient (∼4 Gyr) super-earths may be partially molten at the top and bottom of their mantles, and that mantle convection is sufficiently vigorous to sustain dynamo action over the whole range of super-earth masses.

  8. Development of educational programs using Dagik Earth, a four dimensional display of the Earth and planets

    NASA Astrophysics Data System (ADS)

    Saito, A.; Akiya, Y.; Yoshida, D.; Odagi, Y.; Yoshikawa, M.; Tsugawa, T.; Takahashi, M.; Kumano, Y.; Iwasaki, S.

    2010-12-01

    We have developed a four-dimensional display system of the Earth and planets to use in schools, science centers, and research institutes. It can display the Earth and planets in three-dimensional way without glasses, and the time variation of the scientific data can be displayed on the Earth and planets image. The system is named Dagik Earth, and educational programs using Dagik Earth have been developed for schools and science centers. Three dimensional displays can show the Earth and planets in exact form without any distortion, which cannot be achieved with two-dimensional display. Furthermore it can provide a sense of reality. There are several systems for the three-dimensional presentation of the Earth, such as Science on a sphere by NOAA, and Geocosmos by Miraikan, Japan. Comparing these systems, the advantage of Dagik Earth is portability and affordability. The system uses ordinary PC and PC projector. Only a spherical screen is the special equipment of Dagik Earth. Therefore Dagik Earth is easy to use in classrooms. Several educational programs have been developed and carried out in high schools, junior high schools, elementary schools and science centers. Several research institutes have used Dagik Earth in their public outreach programs to demonstrate their novel scientific results to public in an attractive way of presentation. A community of users and developers of Dagik Earth is being formed in Japan. In the presentation, the outline of Dagik Earth and the educational programs using Dagik Earth will be presented. Its future plan will also be discussed.

  9. Earth Day 2017

    NASA Image and Video Library

    2017-12-08

    Happy Earth Day! Explore the diverse colors, unique shapes and striking patterns of our very favorite planet, Earth - as only NASA can see it. Credit: NASA/Goddard #nasagoddard NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

  10. Maladie de Kaposi à localisation broncho-pulmonaire révélant une infection VIH

    PubMed Central

    Sebbar, Amal; Zaghba, Nahid; Benjelloun, Hanane; Bakhatar, Abdelaziz; Yassine, Najiba

    2015-01-01

    La maladie de Kaposi (MK) associée au VIH, forme dite épidémique, a été décrite la 1ère fois en 1981 par Hymmes. C'est l'affection maligne la plus fréquente au cours du SIDA. La MK est à l'origine de 10% des atteintes pleuropulmonaires au cours de l'infection par le VIH et 40% des pneumopathies en cas de MK cutanéomuqueuse. Les localisations pulmonaires occupent la deuxième place des atteintes viscérales après la forme digestive. Le diagnostic repose sur des arguments épidémiologiques, cliniques, radiologiques, biologiques, endoscopiques et histologiques. Nous rapportons un cas de MK broncho-pulmonaire compliquant une infection VIH chez un patient présentant une maladie de Kaposi cutanée de découverte fortuite au cours de l'atteinte pulmonaire. Le diagnostic a été retenu après avoir éliminé les maladies opportunistes à tropisme pulmonaire. Le Kaposi pulmonaire constitue l'atteinte la plus grave de la MK-sida et la survie après le diagnostic est courte malgré les thérapeutiques agressives. PMID:26958142

  11. Earth - Pacific Ocean

    NASA Image and Video Library

    1996-01-29

    This color image of the Earth was obtained by NASA’s Galileo spacecraft early Dec. 12, 1990, when the spacecraft was about 1.6 million miles from the Earth. http://photojournal.jpl.nasa.gov/catalog/PIA00123

  12. Effets tardifs d'une irradiation corporelle totale sur le métabolisme intraneuronal de la dopamine et de la sérotonine

    NASA Astrophysics Data System (ADS)

    Joubert, C.; Jacquet, N.; Lambert, F.; Martin, S.; Martin, C.

    1998-04-01

    Whole-body irradiation leads to delayed cognitive dysfunction which could result from perturbations of neurotransmission, specially the dopaminergic and the serotoninergic one. The aim of this study was to determine the concentrations of dopamine (DA), serotonin (5-HT) and their metabolites in three cerebral areas of rats, one month after (neutron-gamma) irradiation at 3.38Gy. An increase of DA, 5-HT, and their catabolites was observed. These effects are weak but observed in older rats. Au cours des mois suivant une irradiation corporell totale peuvent se manifester des troubles comportementaux qui pourraient être la conséquence d'altérations de la neuraotransmission, plus particulièrement de la transmission dopaminergique ou sérotoninergique. Nous avons recherché les variations des taux de dopamine (DA), de sérotonine (5-HT) et de leurs métabolites dans 3structures cérébrales 1 mois après une irradiation (neutron-gamma) à la dose de 3,38Gy. Les résultats préliminaires mettent en évidence une augmentation des taux de DA, de 5-HT et de leurs catabolites ; ces effets sont plus discrets mais similaires à ceux observés chez des animaux plus âgés.

  13. Accretion of the Earth.

    PubMed

    Canup, Robin M

    2008-11-28

    The origin of the Earth and its Moon has been the focus of an enormous body of research. In this paper I review some of the current models of terrestrial planet accretion, and discuss assumptions common to most works that may require re-examination. Density-wave interactions between growing planets and the gas nebula may help to explain the current near-circular orbits of the Earth and Venus, and may result in large-scale radial migration of proto-planetary embryos. Migration would weaken the link between the present locations of the planets and the original provenance of the material that formed them. Fragmentation can potentially lead to faster accretion and could also damp final planet orbital eccentricities. The Moon-forming impact is believed to be the final major event in the Earth's accretion. Successful simulations of lunar-forming impacts involve a differentiated impactor containing between 0.1 and 0.2 Earth masses, an impact angle near 45 degrees and an impact speed within 10 per cent of the Earth's escape velocity. All successful impacts-with or without pre-impact rotation-imply that the Moon formed primarily from material originating from the impactor rather than from the proto-Earth. This must ultimately be reconciled with compositional similarities between the Earth and the Moon.

  14. Early Earth slab stagnation

    NASA Astrophysics Data System (ADS)

    Agrusta, R.; Van Hunen, J.

    2016-12-01

    At present day, the Earth's mantle exhibits a combination of stagnant and penetrating slabs within the transition zone, indicating a intermittent convection mode between layered and whole-mantle convection. Isoviscous thermal convection calculations show that in a hotter Earth, the natural mode of convection was dominated by double-layered convection, which may imply that slabs were more prone to stagnate in the transition zone. Today, slab penetration is to a large extent controlled by trench mobility for a plausible range of lower mantle viscosity and Clapeyron slope of the mantle phase transitions. Trench mobility is, in turn, governed by slab strength and density and upper plate forcing. In this study, we systematically investigate the slab-transition zone internation in the Early Earth, using 2D self-consistent numerical subduction models. Early Earth's higher mantle temperature facilitates decoupling between the plates and the underlying asthenosphere, and may result in slab sinking almost without trench retreat. Such behaviour together with a low resistance of a weak lower mantle may allow slabs to penetrate. The ability of slab to sink into the lower mantle throughout Earth's history may have important implications for Earth's evolution: it would provide efficient mass and heat flux through the transition zone therefore provide an efficient way to cool and mix the Earth's mantle.

  15. Venus, Earth, Xenon

    NASA Astrophysics Data System (ADS)

    Zahnle, K. J.

    2013-12-01

    Xenon has been regarded as an important goal of many proposed missions to Venus. This talk is intended to explain why. Despite its being the heaviest gas found in natural planetary atmospheres, there is more evidence that Xe escaped from Earth than for any element apart from helium: (i) Atmospheric Xe is very strongly mass fractionated (at about 4% per amu) from any known solar system source. This suggests fractionating escape that preferentially left the heavy Xe isotopes behind. (ii) Xe is underabundant compared to Kr, a lighter noble gas that is not strongly mass fractionated in air. (iii) Radiogenic Xe is strongly depleted by factors of several to ~100 compared to the quantities expected from radioactive decay of primordial solar system materials. In these respects Xe on Mars is similar to Xe on Earth, but with one key difference: Xe on Mars is readily explained by a simple process like hydrodynamic escape that acts on an initially solar or meteoritic Xe. This is not so for Earth. Earth's Xe cannot be derived by an uncontrived mass fractionating process acting on any known type of Solar System Xe. Earth is a stranger, made from different stuff than any known meteorite or Mars or even the Sun. Who else is in Earth's family? Comets? We know nothing. Father Zeus? Data from Jupiter are good enough to show that jovian Xe is not strongly mass-fractionated but not good enough to determine whether Jupiter resembles the Earth or the Sun. Sister Venus? Noble gas data from Venus are incomplete, with Kr uncertain and Xe unmeasured. Krypton was measured by several instruments on several spacecraft. The reported Kr abundances are discrepant and were once highly controversial. These discrepancies appear to have been not so much resolved as forgotten. Xenon was not detected on Venus. Upper limits were reported for the two most abundant xenon isotopes 129Xe and 132Xe. From the limited data it is not possible to tell whether Venus's affinities lie with the solar wind, or with

  16. NASA's mission to planet Earth: Earth observing system

    NASA Technical Reports Server (NTRS)

    1993-01-01

    The topics covered include the following: global climate change; radiation, clouds, and atmospheric water; the ocean; the troposphere - greenhouse gases; land cover and the water cycle; polar ice sheets and sea level; the stratosphere - ozone chemistry; volcanoes; the Earth Observing System (EOS) - how NASA will support studies of global climate change?; research and assessment - EOS Science Investigations; EOS Data and Information System (EOSDIS); EOS observations - instruments and spacecraft; a national international effort; and understanding the Earth System.

  17. Earth's earliest atmospheres.

    PubMed

    Zahnle, Kevin; Schaefer, Laura; Fegley, Bruce

    2010-10-01

    Earth is the one known example of an inhabited planet and to current knowledge the likeliest site of the one known origin of life. Here we discuss the origin of Earth's atmosphere and ocean and some of the environmental conditions of the early Earth as they may relate to the origin of life. A key punctuating event in the narrative is the Moon-forming impact, partly because it made Earth for a short time absolutely uninhabitable, and partly because it sets the boundary conditions for Earth's subsequent evolution. If life began on Earth, as opposed to having migrated here, it would have done so after the Moon-forming impact. What took place before the Moon formed determined the bulk properties of the Earth and probably determined the overall compositions and sizes of its atmospheres and oceans. What took place afterward animated these materials. One interesting consequence of the Moon-forming impact is that the mantle is devolatized, so that the volatiles subsequently fell out in a kind of condensation sequence. This ensures that the volatiles were concentrated toward the surface so that, for example, the oceans were likely salty from the start. We also point out that an atmosphere generated by impact degassing would tend to have a composition reflective of the impacting bodies (rather than the mantle), and these are almost without exception strongly reducing and volatile-rich. A consequence is that, although CO- or methane-rich atmospheres are not necessarily stable as steady states, they are quite likely to have existed as long-lived transients, many times. With CO comes abundant chemical energy in a metastable package, and with methane comes hydrogen cyanide and ammonia as important albeit less abundant gases.

  18. Earth Science Informatics - Overview

    NASA Technical Reports Server (NTRS)

    Ramapriyan, H. K.

    2017-01-01

    Over the last 10-15 years, significant advances have been made in information management, there are an increasing number of individuals entering the field of information management as it applies to Geoscience and Remote Sensing data, and the field of informatics has come to its own. Informatics is the science and technology of applying computers and computational methods to the systematic analysis, management, interchange, and representation of science data, information, and knowledge. Informatics also includes the use of computers and computational methods to support decision making and applications. Earth Science Informatics (ESI, a.k.a. geoinformatics) is the application of informatics in the Earth science domain. ESI is a rapidly developing discipline integrating computer science, information science, and Earth science. Major national and international research and infrastructure projects in ESI have been carried out or are on-going. Notable among these are: the Global Earth Observation System of Systems (GEOSS), the European Commissions INSPIRE, the U.S. NSDI and Geospatial One-Stop, the NASA EOSDIS, and the NSF DataONE, EarthCube and Cyberinfrastructure for Geoinformatics. More than 18 departments and agencies in the U.S. federal government have been active in Earth science informatics. All major space agencies in the world, have been involved in ESI research and application activities. In the United States, the Federation of Earth Science Information Partners (ESIP), whose membership includes over 180 organizations (government, academic and commercial) dedicated to managing, delivering and applying Earth science data, has been working on many ESI topics since 1998. The Committee on Earth Observation Satellites (CEOS)s Working Group on Information Systems and Services (WGISS) has been actively coordinating the ESI activities among the space agencies.The talk will present an overview of current efforts in ESI, the role members of IEEE GRSS play, and discuss

  19. Une urgence médico-chirurgicale rare: l’abcès épidural rachidien (à propos de 03 cas)

    PubMed Central

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

    2017-01-01

    Les infections de l’espace épidural sont de mieux en mieux connues grâce au développement de la neurochirurgie, notamment l’IRM. Les abcès épiduraux rachidiens représentent une pathologie rare mais éminemment grave sur le plan fonctionnel, avec un risque vital potentiel. Nous rapportons trois cas d’abcès épidural rachidien tous diagnostiqués chez des patients de sexe masculin, le premier âgé de 52 ans le deuxième de 57 ans et le troisième de 63ans. Deux patients ont été admis aux urgences neurochirurgicales pour un tableau de compression médullaire lente évoluant dans un contexte infectieux, et le dernier se plaignait d’une sciatique S1 droite rebelle au traitement avec des fuites urinaires. Aucune porte d’entrée n’a été identifiée dans le bilan initial. Tous les patients ont été opérés par voie d’abord postérieure avec décompression médullaire/radiculaire et évacuation de l’abcès épidural. L’étude bactériologique a trouvé un germe pyogène justifiant une antibiothérapie adaptée dans les trois cas. L’évolution a été favorable dans deux cas. Par contre un patient est décédé trois jours en post-opératoire par un sepsis sévère. PMID:28533868

  20. Direct and indirect capture of near-Earth asteroids in the Earth-Moon system

    NASA Astrophysics Data System (ADS)

    Tan, Minghu; McInnes, Colin; Ceriotti, Matteo

    2017-09-01

    Near-Earth asteroids have attracted attention for both scientific and commercial mission applications. Due to the fact that the Earth-Moon L1 and L2 points are candidates for gateway stations for lunar exploration, and an ideal location for space science, capturing asteroids and inserting them into periodic orbits around these points is of significant interest for the future. In this paper, we define a new type of lunar asteroid capture, termed direct capture. In this capture strategy, the candidate asteroid leaves its heliocentric orbit after an initial impulse, with its dynamics modeled using the Sun-Earth-Moon restricted four-body problem until its insertion, with a second impulse, onto the L2 stable manifold in the Earth-Moon circular restricted three-body problem. A Lambert arc in the Sun-asteroid two-body problem is used as an initial guess and a differential corrector used to generate the transfer trajectory from the asteroid's initial obit to the stable manifold associated with Earth-Moon L2 point. Results show that the direct asteroid capture strategy needs a shorter flight time compared to an indirect asteroid capture, which couples capture in the Sun-Earth circular restricted three-body problem and subsequent transfer to the Earth-Moon circular restricted three-body problem. Finally, the direct and indirect asteroid capture strategies are also applied to consider capture of asteroids at the triangular libration points in the Earth-Moon system.

  1. Earth Orientation - Naval Oceanography Portal

    Science.gov Websites

    section Advanced Search... Sections Home Time Earth Orientation Astronomy Meteorology Oceanography Ice You are here: Home › USNO › Earth Orientation USNO Logo USNO Navigation Earth Orientation Products GPS -based Products VLBI-based Products EO Information Center Publications about Products Software Info Earth

  2. Earthing Spiritual Literacy: How to Link Spiritual Development and Education to a New Earth Consciousness?

    ERIC Educational Resources Information Center

    King, Ursula

    2010-01-01

    This article discusses the development of spiritual literacy in relation to a new consciousness of the Earth and what Thomas Berry calls "Earth literacy". It draws on the metaphor of "earthing" to argue for a close link between spiritual literacy and Earth literacy, considered of great importance for both personal spiritual…

  3. Not So Rare Earth? New Developments in Understanding the Origin of the Earth and Moon

    NASA Technical Reports Server (NTRS)

    Righter, Kevin

    2007-01-01

    A widely accepted model for the origin of the Earth and Moon has been a somewhat specific giant impact scenario involving an impactor to proto-Earth mass ratio of 3:7, occurring 50-60 Ma after T(sub 0), when the Earth was only half accreted, with the majority of Earth's water then accreted after the main stage of growth, perhaps from comets. There have been many changes to this specific scenario, due to advances in isotopic and trace element geochemistry, more detailed, improved, and realistic giant impact and terrestrial planet accretion modeling, and consideration of terrestrial water sources other than high D/H comets. The current scenario is that the Earth accreted faster and differentiated quickly, the Moon-forming impact could have been mid to late in the accretion process, and water may have been present during accretion. These new developments have broadened the range of conditions required to make an Earth-Moon system, and suggests there may be many new fruitful avenues of research. There are also some classic and unresolved problems such as the significance of the identical O isotopic composition of the Earth and Moon, the depletion of volatiles on the lunar mantle relative to Earth's, the relative contribution of the impactor and proto-Earth to the Moon's mass, and the timing of Earth's possible atmospheric loss relative to the giant impact.

  4. Exploring Spaceship Earth

    ERIC Educational Resources Information Center

    McInnis, Noel F.

    1973-01-01

    Describes various activities to understand the nature of the earth as a spaceship and its impact on human life. A figure depicting a holocoenotic environmental complex is given which can be used to illustrate various interacting forces on earth. (PS)

  5. The Group on Earth Observations and the Global Earth Observation System of Systems

    NASA Astrophysics Data System (ADS)

    Achache, J.

    2006-05-01

    The Group on Earth Observations (GEO) is leading a worldwide effort to build a Global Earth Observation System of Systems (GEOSS) over the next 10 years. The GEOSS vision, articulated in its 10-Year Implementation Plan, represents the consolidation of a global scientific and political consensus: the assessment of the state of the Earth requires continuous and coordinated observation of our planet at all scales. GEOSS aims to achieve comprehensive, coordinated and sustained observations of the Earth system in order to improve monitoring of the state of the Earth; increase understanding of Earth processes; and enhance prediction of the behaviour of the Earth system. After the World Summit on Sustainable Development in 2002 highlighted the urgent need for coordinated observations relating to the state of the Earth, GEO was established at the Third Earth Observation Summit in February 2005 and the GEOSS 10-Year Implementation Plan was endorsed. GEO currently involves 60 countries; the European Commission; and 43 international organizations and has begun implementation of the GEOSS 10-Year Implementation Plan. GEO programme activities cover nine societal benefit areas (Disasters; Health; Energy; Climate; Water; Weather; Ecosystems; Agriculture; Biodiversity) and five transverse or crosscutting elements (User Engagement; Architecture; Data Management; Capacity Building; Outreach). All these activities have as their final goal the establishment of the "system of systems" which will yield a broad range of basic societal benefits, including the reduction of loss of life and property from tsunamis, hurricanes, and other natural disasters; improved water resource and energy management; and improved understanding of environmental factors significant to public health. As a "system of systems", GEOSS will work with and build upon existing national, regional, and international systems to provide comprehensive, coordinated Earth observations from thousands of instruments worldwide

  6. PREFACE: 2013 International Conferences on Geological, Geographical, Aerospace and Earth Sciences (AeroEarth 2013)

    NASA Astrophysics Data System (ADS)

    2014-03-01

    The 2013 International Conferences on Geological, Geographical, Aerospace and Earth Sciences (AeroEarth 2013), was held at the Swiss Bell Mangga Besar, Jakarta, Indonesia, on 23 December 2013. The AeroEarth conference aims to bring together researchers, engineers and scientists in the domain of interest from around the world. AeroEarth 2013 promotes interaction between the theoretical, experimental, and applied communities, so that high-level exchange is achieved in new and emerging areas within Earth Science. Through research and development, earth scientists have the power to preserve the planet's different resource domains by providing expert opinion and information about the forces which make life possible on Earth. We would like to express our sincere gratitude to all in the Technical Program Committee who have reviewed the papers and developed a very interesting Conference Program as well as the invited and plenary speakers. This year, we received 91 papers and after rigorous review, 17 papers were accepted. The participants come from 8 countries. There are 3 (three) Plenary Sessions and two invited Speakers. It is an honour to present this volume of IOP Conference Series: Earth and Environmental Science (EES) and we deeply thank the authors for their enthusiastic and high-grade contribution. Finally, we would like to thank the conference chairmen, the members of the steering committee, the organizing committee, the organizing secretariat and the financial support from the conference sponsors that allowed the success of AeroEarth 2013. The AeroEarth 2013 Proceedings Editors Dr. Ford Lumban Gaol Dr. Benfano Soewito Dr. Amit Desai Further information on the invited plenary speakers and photographs from the conference can be found in the pdf.

  7. Modeling the Earth system in the Mission to Planet Earth era

    NASA Technical Reports Server (NTRS)

    Unninayar, Sushel; Bergman, Kenneth H.

    1993-01-01

    A broad overview is made of global earth system modeling in the Mission to Planet Earth (MTPE) era for the multidisciplinary audience encompassed by the Global Change Research Program (GCRP). Time scales of global system fluctuation and change are described in Section 2. Section 3 provides a rubric for modeling the global earth system, as presently understood. The ability of models to predict the future state of the global earth system and the extent to which their predictions are reliable are covered in Sections 4 and 5. The 'engineering' use of global system models (and predictions) is covered in Section 6. Section 7 covers aspects of an increasing need for improved transform algorithms and better methods to assimilate this information into global models. Future monitoring and data requirements are detailed in Section 8. Section 9 covers the NASA-initiated concept 'Mission to Planet Earth,' which employs space and ground based measurement systems to provide the scientific basis for understanding global change. Section 10 concludes this review with general remarks concerning the state of global system modeling and observing technology and the need for future research.

  8. Introduction à une théorie des systèmes composites : exemples simples de matériaux lamellaires

    NASA Astrophysics Data System (ADS)

    Akjouj, A.; Sylla, B.; Dobrzynski, L.

    This review paper is mostly an introduction to the linear response theory for composite systems. The composite materials are defined here as being formed by different homogeneous parts connected together by interfaces. This type of material can be constructed with the help of homogeneous "bricks" cuted out from infinite materials. This cutting procedures are realized with the help of cleavage operators. The "bricks" are then put together by a coupling operator. This construction manner enables to obtain for any composite system a general equation relating the composite response function (called also Green's function) to the elements of the infinite material response functions and to the cleavage and coupling operators. A general and unified formulation valid as well in matrix algebra as in the algebra of differential equations results from this approach. Any general theory is abstract ; simple examples help very much to understand it. The principal aim of this review paper is the introduction of a general theory for composite systems through simple and analytical examples from the fields of phonons, magnons and electrons in the lamellar composite materials. In order to achieve this goal, the algebra of the examples is as explicit as possible. The references of what was already realized in theory of composite response are discussed also. A prospective and non exhaustive study of all the fields where such a theory can prove to be helpful is given also in this review paper. Cet article de revue est essentiellement une introduction à la théorie de la réponse linéaire dans les systèmes composites. Les matériaux composites sont définis ici comme étant formés de parties homogènes différentes reliées par des interfaces. Ce type de matériaux peut être construit à partir de "briques" homogènes découpées dans des matériaux infinis. Ces opérations de découpage sont effectuées par l'intermédiaire d'opérateurs de clivage. Les "briques" sont ensuite

  9. Sun-Earth Scientists and Native Americans Collaborate on Sun-Earth Day

    NASA Astrophysics Data System (ADS)

    Ng, C. Y.; Lopez, R. E.; Hawkins, I.

    2004-12-01

    Sun-Earth Connection scientists have established partnerships with several minority professional societies to reach out to the blacks, Hispanics and Native American students. Working with NSBP, SACNAS, AISES and NSHP, SEC scientists were able to speak in their board meetings and national conferences, to network with minority scientists, and to engage them in Sun-Earth Day. Through these opportunities and programs, scientists have introduced NASA research results as well indigenous views of science. They also serve as role models in various communities. Since the theme for Sun-Earth Day 2005 is Ancient Observatories: Timeless Knowledge, scientists and education specialists are hopeful to excite many with diverse backgrounds. Sun-Earth Day is a highly visible annual program since 2001 that touches millions of students and the general public. Interviews, classroom activities and other education resources are available on the web at sunearthday.nasa.gov.

  10. PREFACE: 3rd International Conference on Geological, Geographical, Aerospace and Earth Science 2015 (AeroEarth 2015)

    NASA Astrophysics Data System (ADS)

    Gaol, F. L.

    2016-02-01

    The 3rd International Conferences on Geological, Geographical, Aerospaces and Earth Sciences 2015 (AeroEarth 2015), was held at The DoubleTree Hilton, Jakarta, Indonesia during 26 - 27 September 2015. The 1st AeoroEarth was held succefully in Jakarta in 2013. The success continued to The 2nd AeroEarth 2014 that was held in Kuta Bali, Indonesia. The publications were published by EES IOP in http://iopscience.iop.org/1755-1315/19/1 and http://iopscience.iop.org/1755-1315/23/1 respectively. The AeroEarth 2015 conference aims to bring together researchers, engineers and scientists from around the world. Through research and development, Earth's scientists have the power to preserve the planet's different resource domains by providing expert opinion and information about the forces which make life possible on Earth. The theme of AeroEarth 2015 is ''Earth and Aerospace Sciences : Challenges and Opportunities'' Earth provides resources and the exact conditions to make life possible. However, with the advent of technology and industrialization, the Earth's resources are being pushed to the brink of depletion. Non-sustainable industrial practices are not only endangering the supply of the Earth's natural resources, but are also putting burden on life itself by bringing about pollution and climate change. A major role of earth science scholars is to examine the delicate balance between the Earth's resources and the growing demands of industrialization. Through research and development, earth scientists have the power to preserve the planet's different resource domains by providing expert opinion and information about the forces which make life possible on Earth. We would like to express our sincere gratitude to all in the Technical Program Committee who have reviewed the papers and developed a very interesting Conference Program as well as the invited and plenary speakers. This year, we received 78 papers and after rigorous review, 18 papers were accepted. The participants

  11. Caracterisation environnementale des emissions atmospheriques d'une source fixe et creation d'un outil de gestion dynamique =

    NASA Astrophysics Data System (ADS)

    Fournier, Marie-Claude

    Une caracterisation des emissions atmospheriques provenant des sources fixes en operation, alimentees au gaz et a l'huile legere, a ete conduite aux installations visees des sites no.1 et no.2. La caracterisation et les calculs theoriques des emissions atmospheriques aux installations des sites no.1 et no.2 presentent des resultats qui sont en dessous des valeurs reglementaires pour des conditions d'operation normales en periode hivernale et par consequent, a de plus fortes demandes energetiques. Ainsi, pour une demande energetique plus basse, le taux de contaminants dans les emissions atmospheriques pourrait egalement etre en dessous des reglementations municipales et provinciales en vigueur. Dans la perspective d'une nouvelle reglementation provinciale, dont les termes sont discutes depuis 2005, il serait souhaitable que le proprietaire des infrastructures visees participe aux echanges avec le Ministere du Developpement Durable, de l'Environnement et des Parcs (MDDEP) du Quebec. En effet, meme si le principe de droit acquis permettrait d'eviter d'etre assujetti a la nouvelle reglementation, l'application de ce type de principe ne s'inscrit pas dans ceux d'un developpement durable. L'âge avance des installations etudiees implique la planification d'un entretien rigoureux afin d'assurer les conditions optimales de combustion en fonction du type de combustible. Des tests de combustion sur une base reguliere sont donc recommandes. Afin de supporter le processus de suivi et d'evaluation de la performance environnementale des sources fixes, un outil d'aide a la gestion de l'information environnementale a ete developpe. Dans ce contexte, la poursuite du developpement d'un outil d'aide a la gestion de l'information environnementale faciliterait non seulement le travail des personnes affectees aux inventaires annuels mais egalement le processus de communication entre les differents acteurs concernes tant intra- qu'inter-etablissement. Cet outil serait egalement un bon

  12. Baltic Earth - Earth System Science for the Baltic Sea Region

    NASA Astrophysics Data System (ADS)

    Meier, Markus; Rutgersson, Anna; Lehmann, Andreas; Reckermann, Marcus

    2014-05-01

    The Baltic Sea region, defined as its river catchment basin, spans different climate and population zones, from a temperate, highly populated, industrialized south with intensive agriculture to a boreal, rural north. It encompasses most of the Scandinavian Peninsula in the west; most of Finland and parts of Russia, Belarus, and the Baltic states in the east; and Poland and small parts of Germany and Denmark in the south. The region represents an old cultural landscape, and the Baltic Sea itself is among the most studied sea areas of the world. Baltic Earth is the new Earth system research network for the Baltic Sea region. It is the successor to BALTEX, which was terminated in June 2013 after 20 years and two successful phases. Baltic Earth stands for the vision to achieve an improved Earth system understanding of the Baltic Sea region. This means that the research disciplines of BALTEX continue to be relevant, i.e. atmospheric and climate sciences, hydrology, oceanography and biogeochemistry, but a more holistic view of the Earth system encompassing processes in the atmosphere, on land and in the sea as well as in the anthroposphere shall gain in importance in Baltic Earth. Specific grand research challenges have been formulated, representing interdisciplinary research questions to be tackled in the coming years. A major means will be scientific assessments of particular research topics by expert groups, similar to the BACC approach, which shall help to identify knowledge gaps and develop research strategies. Preliminary grand challenges and topics for which Working Groups have been installed include: • Salinity dynamics in the Baltic Sea • Land-Sea biogeochemical feedbacks in the Baltic Sea region • Natural hazards and extreme events in the Baltic Sea region • Understanding sea level dynamics in the Baltic Sea • Understanding regional variability of water and energy exchange • Utility of Regional Climate Models • Assessment of Scenario Simulations

  13. Macro-adénome surrénalien masquant une hyperplasie micronodulaire des surrénales au cours d’un syndrome de Cushing ACTH indépendant et hypokaliémie réfractaire

    PubMed Central

    Alaya, Wafa; Bouchahda, Haifa; Fradi, Asma; Zantour, Baha; Sfar, Mohamed Habib

    2017-01-01

    L’association d’une hyperplasie micronodulaire des surrénales à un macro-adénome surrénalien au cours d’un syndrome de Cushing (SC) ACTH-indépendant est rare et suscite beaucoup de questions. Nous en rapportons un cas. Patiente âgée de 35 ans nous a été adressée pour suspicion d’un SC devant une obésité facio-tronculaire avec hypokaliémie d’origine rénale. Les explorations hormonales ont objectivé un SC ACTH-indépendant et le scanner abdominal a montré macro-adénome surrénalien gauche de 2cm avec une surrénale droite normale. La patiente a eu une surrénalectomie gauche. Cependant, l’hypercortisolisme et l’hypokaliémie ont persisté. L’examen anatomopathologique a permis de conclure à un adénome corticosurrénalien de 2,5cm, avec une hyperplasie micronodulaire non pigmentée des surrénales (i-MAD). La patiente a eu une surrénalectomie droite, suivie d’une insuffisance surrénalienne. Paradoxalement, l’hypokaliémie a persisté sans autres anomalies ni explication évidente (magnésémie, pH sanguin et urinaire, bilan phosphocalcique et échographie rénale normaux) nécessitant une supplémentation parentérale puis orale par du KCl. The association between micronodular adrenal hyperplasia and macro-adrenal adenoma in patients with ACTH-independent Cushing’s syndrome (CS) is rare and raises a lot of questions. We here report the case of a 35-year old female patient referred to us for suspected CS due to central obesity associated with renal hypokalaemia. Hormonal explorations objectified ACTH-independent CS and abdominal CT scan showed left macro-adrenal adenoma measuring 2cm in diameter associated with normal right adrenal gland. The patient underwent left adrenalectomy. However, hypercortisolism and hypokalaemia persisted. Anatomo-pathological examination allowed the diagnisis of adrenocortical adenoma measuring 2,5cm in diameter associated with unpigmented micronodular adrenal hyperplasia (i-Mad). The patient

  14. Rotation of a Moonless Earth

    NASA Technical Reports Server (NTRS)

    Lissauer, Jack J.; Barnes, Jason W.; Chambers, John E.

    2013-01-01

    We numerically explore the obliquity (axial tilt) variations of a hypothetical moonless Earth. Previous work has shown that the Earth's Moon stabilizes Earth's obliquity such that it remains within a narrow range, between 22.1 deg and 24.5 deg. Without lunar influence, a frequency-map analysis by Laskar et al. showed that the obliquity could vary between 0 deg. and 85 deg. This has left an impression in the astrobiology community that a large moon is necessary to maintain a habitable climate on an Earth-like planet. Using a modified version of the orbital integrator mercury, we calculate the obliquity evolution for moonless Earths with various initial conditions for up to 4 Gyr. We find that while obliquity varies significantly more than that of the actual Earth over 100,000 year timescales, the obliquity remains within a constrained range, typically 20-25 deg. in extent, for timescales of hundreds of millions of years. None of our Solar System integrations in which planetary orbits behave in a typical manner show obliquity accessing more than 65% of the full range allowed by frequency-map analysis. The obliquities of moonless Earths that rotate in the retrograde direction are more stable than those of pro-grade rotators. The total obliquity range explored for moonless Earths with rotation periods shorter than 12 h is much less than that for slower-rotating moonless Earths. A large moon thus does not seem to be needed to stabilize the obliquity of an Earth-like planet on timescales relevant to the development of advanced life.

  15. Biosignatures of early earths

    NASA Technical Reports Server (NTRS)

    Pilcher, Carl B.

    2003-01-01

    A major goal of NASA's Origins Program is to find habitable planets around other stars and determine which might harbor life. Determining whether or not an extrasolar planet harbors life requires an understanding of what spectral features (i.e., biosignatures) might result from life's presence. Consideration of potential biosignatures has tended to focus on spectral features of gases in Earth's modern atmosphere, particularly ozone, the photolytic product of biogenically produced molecular oxygen. But life existed on Earth for about 1(1/2) billion years before the buildup of atmospheric oxygen. Inferred characteristics of Earth's earliest biosphere and studies of modern microbial ecosystems that share some of those characteristics suggest that organosulfur compounds, particularly methanethiol (CH(3)SH, the sulfur analog of methanol), may have been biogenic products on early Earth. Similar production could take place on extrasolar Earth-like planets whose biota share functional chemical characteristics with Earth life. Since methanethiol and related organosulfur compounds (as well as carbon dioxide) absorb at wavelengths near or overlapping the 9.6-microm band of ozone, there is potential ambiguity in interpreting a feature around this wavelength in an extrasolar planet spectrum.

  16. Biosignatures of early earths.

    PubMed

    Pilcher, Carl B

    2003-01-01

    A major goal of NASA's Origins Program is to find habitable planets around other stars and determine which might harbor life. Determining whether or not an extrasolar planet harbors life requires an understanding of what spectral features (i.e., biosignatures) might result from life's presence. Consideration of potential biosignatures has tended to focus on spectral features of gases in Earth's modern atmosphere, particularly ozone, the photolytic product of biogenically produced molecular oxygen. But life existed on Earth for about 1(1/2) billion years before the buildup of atmospheric oxygen. Inferred characteristics of Earth's earliest biosphere and studies of modern microbial ecosystems that share some of those characteristics suggest that organosulfur compounds, particularly methanethiol (CH(3)SH, the sulfur analog of methanol), may have been biogenic products on early Earth. Similar production could take place on extrasolar Earth-like planets whose biota share functional chemical characteristics with Earth life. Since methanethiol and related organosulfur compounds (as well as carbon dioxide) absorb at wavelengths near or overlapping the 9.6-microm band of ozone, there is potential ambiguity in interpreting a feature around this wavelength in an extrasolar planet spectrum.

  17. Earth on the Horizon

    NASA Image and Video Library

    2004-03-13

    This is the first image ever taken of Earth from the surface of a planet beyond the Moon. It was taken by the Mars Exploration Rover Spirit one hour before sunrise on the 63rd martian day, or sol, of its mission. Earth is the tiny white dot in the center. The image is a mosaic of images taken by the rover's navigation camera showing a broad view of the sky, and an image taken by the rover's panoramic camera of Earth. The contrast in the panoramic camera image was increased two times to make Earth easier to see. http://photojournal.jpl.nasa.gov/catalog/PIA05560

  18. EarthCache as a Tool to Promote Earth-Science in Public School Classrooms

    NASA Astrophysics Data System (ADS)

    Gochis, E. E.; Rose, W. I.; Klawiter, M.; Vye, E. C.; Engelmann, C. A.

    2011-12-01

    Geoscientists often find it difficult to bridge the gap in communication between university research and what is learned in the public schools. Today's schools operate in a high stakes environment that only allow instruction based on State and National Earth Science curriculum standards. These standards are often unknown by academics or are written in a style that obfuscates the transfer of emerging scientific research to students in the classroom. Earth Science teachers are in an ideal position to make this link because they have a background in science as well as a solid understanding of the required curriculum standards for their grade and the pedagogical expertise to pass on new information to their students. As part of the Michigan Teacher Excellence Program (MiTEP), teachers from Grand Rapids, Kalamazoo, and Jackson school districts participate in 2 week field courses with Michigan Tech University to learn from earth science experts about how the earth works. This course connects Earth Science Literacy Principles' Big Ideas and common student misconceptions with standards-based education. During the 2011 field course, we developed and began to implement a three-phase EarthCache model that will provide a geospatial interactive medium for teachers to translate the material they learn in the field to the students in their standards based classrooms. MiTEP participants use GPS and Google Earth to navigate to Michigan sites of geo-significance. At each location academic experts aide participants in making scientific observations about the locations' geologic features, and "reading the rocks" methodology to interpret the area's geologic history. The participants are then expected to develop their own EarthCache site to be used as pedagogical tool bridging the gap between standards-based classroom learning, contemporary research and unique outdoor field experiences. The final phase supports teachers in integrating inquiry based, higher-level learning student

  19. Recycling of rare earth metals from rare earth-transition metal alloy scrap by liquid metal extraction

    DOEpatents

    Ellis, Timothy W.; Schmidt, Frederick A.

    1995-08-01

    Method of treating rare earth metal-bearing scrap, waste or other material (e.g. Nd--Fe--B or Dy--Tb--Fe scrap) to recover the rare earth metal comprising melting the rare earth metal-bearing material, melting a Group IIA metal extractant, such as Mg, Ca, or Ba, in which the rare earth is soluble in the molten state, and contacting the melted material and melted extractant at a temperature and for a time effective to extract the rare earth from the melted material into the melted extractant. The rare earth metal is separated from the extractant metal by vacuum sublimation or distillation.

  20. Earthquake-origin expansion of the Earth inferred from a spherical-Earth elastic dislocation theory

    NASA Astrophysics Data System (ADS)

    Xu, Changyi; Sun, Wenke

    2014-12-01

    In this paper, we propose an approach to compute the coseismic Earth's volume change based on a spherical-Earth elastic dislocation theory. We present a general expression of the Earth's volume change for three typical dislocations: the shear, tensile and explosion sources. We conduct a case study for the 2004 Sumatra earthquake (Mw9.3), the 2010 Chile earthquake (Mw8.8), the 2011 Tohoku-Oki earthquake (Mw9.0) and the 2013 Okhotsk Sea earthquake (Mw8.3). The results show that mega-thrust earthquakes make the Earth expand and earthquakes along a normal fault make the Earth contract. We compare the volume changes computed for finite fault models and a point source of the 2011 Tohoku-Oki earthquake (Mw9.0). The big difference of the results indicates that the coseismic changes in the Earth's volume (or the mean radius) are strongly dependent on the earthquakes' focal mechanism, especially the depth and the dip angle. Then we estimate the cumulative volume changes by historical earthquakes (Mw ≥ 7.0) since 1960, and obtain an Earth mean radius expanding rate about 0.011 mm yr-1.

  1. Fracture panfaciale: un challenge thérapeutique: à propos d'une observation et revue de la littérature

    PubMed Central

    Fassih, Malika; Nassik, Hicham; Abada, Mourad Nafaa Redallah; Rouadi, Sami; Mahta, Mohamed; Roubal, Mohamed; Essaadi, Mustapha; El Kadiri, Mohamed Fatmi

    2015-01-01

    La gestion des traumatismes de la face a subi plusieurs progrès dans la dernière décennie. Avec l'avènement de la tomodensitométrie bi- et tridimensionnelle, qui permet de dresser une cartographie précise des lésions osseuses, le développement du matériel d'ostéosynthèse, et les procédés de réduction des fractures. L'objectif est la restauration totale de la forme et la fonction de la face, seul garant pour empêcher la survenue de préjudices esthétiques et fonctionnels. Nous rapportons l'observation de Mme assal khadija, âgée de 38 ans, admise le 25 Aout 2010, au service des urgences d'ORL et maxillo-faciales, à l'hôpital 20 aout de Casablanca, victime d'un AVP, occasionnant un traumatisme facial grave, avec un important délabrement de la face, et asphyxie. Une trachéotomie a été réalisée en urgence. Le bilan lésionnel a objectivé un important fracas du massif facial intéressant l’étage supérieure, moyen et inférieur. Dans l'immédiat, un parage a été réalisé sous anesthésie générale, la réparation des parties molles délabrées a été effectuée en endobuccale (vestibules, langue et plancher buccal) et pour les téguments de la face. Une semaine après, la patiente a été reprise pour la reconstruction du massif facial, nous avons opté pour le «inside-out, de bas en haut" pour la réduction des fractures. Nous avons procédé à la fixation de la mandibule qui a précédé la reconstruction du maxillaire, de la pyramide nasale, et de l'orbite. L’évolution a été marquée par l'apparition d'un orostome, qui fera l'objet après tarissement de l'infection, d'une réparation grâce à un lambeau myocutané, et une nécrose cutanée de la région zygomatique laissée à la cicatrisation dirigée. Toutes les lésions traumatiques de la face ont des répercussions esthétiques et fonctionnelles à moyen et long termes, dont le degré dépend de la qualité de la prise en charge, qui étant la plus précoce et la plus

  2. Magnetic field of the Earth

    NASA Astrophysics Data System (ADS)

    Popov, Aleksey

    2013-04-01

    The magnetic field of the Earth has global meaning for a life on the Earth. The world geophysical science explains: - occurrence of a magnetic field of the Earth it is transformation of kinetic energy of movements of the fused iron in the liquid core of Earth - into the magnetic energy; - the warming up of a kernel of the Earth occurs due to radioactive disintegration of elements, with excretion of thermal energy. The world science does not define the reasons: - drift of a magnetic dipole on 0,2 a year to the West; - drift of lithospheric slabs and continents. The author offers: an alternative variant existing in a world science the theories "Geodynamo" - it is the theory « the Magnetic field of the Earth », created on the basis of physical laws. Education of a magnetic field of the Earth occurs at moving the electric charge located in a liquid kernel, at rotation of the Earth. At calculation of a magnetic field is used law the Bio Savara for a ring electric current: dB = . Magnetic induction in a kernel of the Earth: B = 2,58 Gs. According to the law of electromagnetic induction the Faradey, rotation of a iron kernel of the Earth in magnetic field causes occurrence of an electric field Emf which moves electrons from the center of a kernel towards the mantle. So of arise the radial electric currents. The magnetic field amplifies the iron of mantle and a kernel of the Earth. As a result of action of a radial electric field the electrons will flow from the center of a kernel in a layer of an electric charge. The central part of a kernel represents the field with a positive electric charge, which creates inverse magnetic field Binv and Emfinv When ?mfinv = ?mf ; ?inv = B, there will be an inversion a magnetic field of the Earth. It is a fact: drift of a magnetic dipole of the Earth in the western direction approximately 0,2 longitude, into a year. Radial electric currents a actions with the basic magnetic field of a Earth - it turn a kernel. It coincides with laws

  3. Our Mission to Planet Earth: A guide to teaching Earth system science

    NASA Technical Reports Server (NTRS)

    1994-01-01

    Volcanic eruptions, hurricanes, floods, and El Nino are naturally occurring events over which humans have no control. But can human activities cause additional environmental change? Can scientists predict the global impacts of increased levels of pollutants in the atmosphere? Will the planet warm because increased levels of greenhouse gases, produced by the burning of fossil fuels, trap heat and prevent it from being radiated back into space? Will the polar ice cap melt, causing massive coastal flooding? Have humans initiated wholesale climatic change? These are difficult questions, with grave implications. Predicting global change and understanding the relationships among earth's components have increased in priority for the nation. The National Aeronautics and Space Administration (NASA), along with many other government agencies, has initiated long-term studies of earth's atmosphere, oceans, and land masses using observations from satellite, balloon, and aircraft-borne instruments. NASA calls its research program Mission to Planet Earth. Because NASA can place scientific instruments far above earth's surface, the program allows scientists to explore earth's components and their interactions on a global scale.

  4. Joint Interdisciplinary Earth Science Information Center

    NASA Technical Reports Server (NTRS)

    Kafatos, Menas

    2004-01-01

    The report spans the three year period beginning in June of 2001 and ending June of 2004. Joint Interdisciplinary Earth Science Information Center's (JIESIC) primary purpose has been to carry out research in support of the Global Change Data Center and other Earth science laboratories at Goddard involved in Earth science, remote sensing and applications data and information services. The purpose is to extend the usage of NASA Earth Observing System data, microwave data and other Earth observing data. JIESIC projects fall within the following categories: research and development; STW and WW prototyping; science data, information products and services; and science algorithm support. JIESIC facilitates extending the utility of NASA's Earth System Enterprise (ESE) data, information products and services to better meet the science data and information needs of a number of science and applications user communities, including domain users such as discipline Earth scientists, interdisciplinary Earth scientists, Earth science applications users and educators.

  5. Moving Closer to EarthScope: A Major New Initiative for the Earth Sciences*

    NASA Astrophysics Data System (ADS)

    Simpson, D.; Blewitt, G.; Ekstrom, G.; Henyey, T.; Hickman, S.; Prescott, W.; Zoback, M.

    2002-12-01

    EarthScope is a scientific research and infrastructure initiative designed to provide a suite of new observational facilities to address fundamental questions about the evolution of continents and the processes responsible for earthquakes and volcanic eruptions. The integrated observing systems that will comprise EarthScope capitalize on recent developments in sensor technology and communications to provide Earth scientists with synoptic and high-resolution data derived from a variety of geophysical sensors. An array of 400 broadband seismometers will spend more than ten years crossing the contiguous 48 states and Alaska to image features that make up the internal structure of the continent and underlying mantle. Additional seismic and electromagnetic instrumentation will be available for high resolution imaging of geological targets of special interest. A network of continuously recording Global Positioning System (GPS) receivers and sensitive borehole strainmeters will be installed along the western U.S. plate boundary. These sensors will measure how western North America is deforming, what motions occur along faults, how earthquakes start, and how magma flows beneath active volcanoes. A four-kilometer deep observatory bored directly into the San Andreas fault will provide the first opportunity to observe directly the conditions under which earthquakes occur, to collect fault rocks and fluids for laboratory study, and to monitor continuously an active fault zone at depth. All data from the EarthScope facilities will be openly available in real-time to maximize participation from the scientific community and to provide on-going educational outreach to students and the public. EarthScope's sensors will revolutionize observational Earth science in terms of the quantity, quality and spatial extent of the data they provide. Turning these data into exciting scientific discovery will require new modes of experimentation and interdisciplinary cooperation from the Earth

  6. Earth science big data at users' fingertips: the EarthServer Science Gateway Mobile

    NASA Astrophysics Data System (ADS)

    Barbera, Roberto; Bruno, Riccardo; Calanducci, Antonio; Fargetta, Marco; Pappalardo, Marco; Rundo, Francesco

    2014-05-01

    The EarthServer project (www.earthserver.eu), funded by the European Commission under its Seventh Framework Program, aims at establishing open access and ad-hoc analytics on extreme-size Earth Science data, based on and extending leading-edge Array Database technology. The core idea is to use database query languages as client/server interface to achieve barrier-free "mix & match" access to multi-source, any-size, multi-dimensional space-time data -- in short: "Big Earth Data Analytics" - based on the open standards of the Open Geospatial Consortium Web Coverage Processing Service (OGC WCPS) and the W3C XQuery. EarthServer combines both, thereby achieving a tight data/metadata integration. Further, the rasdaman Array Database System (www.rasdaman.com) is extended with further space-time coverage data types. On server side, highly effective optimizations - such as parallel and distributed query processing - ensure scalability to Exabyte volumes. In this contribution we will report on the EarthServer Science Gateway Mobile, an app for both iOS and Android-based devices that allows users to seamlessly access some of the EarthServer applications using SAML-based federated authentication and fine-grained authorisation mechanisms.

  7. Crew Earth Observations: Twelve Years of Documenting Earth from the International Space Station

    NASA Technical Reports Server (NTRS)

    Evans, Cynthia A.; Stefanov, William L.; Willis, Kimberley; Runco, Susan; Wilkinson, M. Justin; Dawson, Melissa; Trenchard, Michael

    2012-01-01

    The Crew Earth Observations (CEO) payload was one of the initial experiments aboard the International Space Station, and has been continuously collecting data about the Earth since Expedition 1. The design of the experiment is simple: using state-of-the-art camera equipment, astronauts collect imagery of the Earth's surface over defined regions of scientific interest and also document dynamic events such as storms systems, floods, wild fires and volcanic eruptions. To date, CEO has provided roughly 600,000 images of Earth, capturing views of features and processes on land, the oceans, and the atmosphere. CEO data are less rigorously constrained than other remote sensing data, but the volume of data, and the unique attributes of the imagery provide a rich and understandable view of the Earth that is difficult to achieve from the classic remote sensing platforms. In addition, the length-of-record of the imagery dataset, especially when combined with astronaut photography from other NASA and Russian missions starting in the early 1960s, provides a valuable record of changes on the surface of the Earth over 50 years. This time period coincides with the rapid growth of human settlements and human infrastructure.

  8. Earth Science

    NASA Image and Video Library

    1994-03-08

    Workers at the Astrotech processing facility in Titusville prepared for a news media showing of the Geostationary Operational Environmental Satellite-1 (GOES-1). GOES-1 was the first in a new generation of weather satellites deployed above Earth. It was the first 3-axis, body-stabilized meteorological satellite to be used by the National Oceanic Atmospheric Administration (NOAA) and NASA. These features allowed GOES-1 to continuously monitor the Earth, rather than viewing it just five percent of the time as was the case with spin-stabilized meteorological satellites. GOES-1 also has independent imaging and sounding instruments which can operate simultaneously yet independently. As a result, observations provided by each instrument will not be interrupted. The imager produces visual and infrared images of the Earth's surface, oceans, cloud cover and severe storm development, while the prime sounding products include vertical temperature and moisture profiles, and layer mean moisture.

  9. Earth Observations

    NASA Image and Video Library

    2010-09-09

    ISS024-E-014071 (9 Sept. 2010) --- This striking panoramic view of the southwestern USA and Pacific Ocean is an oblique image photographed by an Expedition 24 crew member looking outwards at an angle from the International Space Station (ISS). While most unmanned orbital satellites view Earth from a nadir perspective?in other words, collecting data with a ?straight down? viewing geometry?crew members onboard the space station can acquire imagery at a wide range of viewing angles using handheld digital cameras. The ISS nadir point (the point on Earth?s surface directly below the spacecraft) was located in northwestern Arizona, approximately 260 kilometers to the east-southeast, when this image was taken. The image includes parts of the States of Arizona, Nevada, Utah, and California together with a small segment of the Baja California, Mexico coastline at center left. Several landmarks and physiographic features are readily visible. The Las Vegas, NV metropolitan area appears as a gray region adjacent to the Spring Mountains and Sheep Range (both covered by white clouds). The Grand Canyon, located on the Colorado Plateau in Arizona, is visible (lower left) to the east of Las Vegas with the blue waters of Lake Mead in between. The image also includes the Mojave Desert, stretching north from the Salton Sea (left) to the Sierra Nevada mountain range. The Sierra Nevada range is roughly 640 kilometers long (north-south) and forms the boundary between the Central Valley of California and the adjacent Basin and Range. The Basin and Range is so called due to the pattern of long linear valleys separated by parallel linear mountain ranges ? this landscape, formed by extension and thinning of Earth?s crust, is particularly visible at right.

  10. The Earth Information Exchange: A Portal for Earth Science From the ESIP Federation

    NASA Astrophysics Data System (ADS)

    Wertz, R.; Hutchinson, C.; Hardin, D.

    2006-12-01

    The Federation of Earth Science Information Partners is a unique consortium of more than 90 organizations that collect, interpret and develop applications for remotely sensed Earth Observation Information. Included in the ESIP network are NASA, NOAA and USGS data centers, research universities, government research laboratories, supercomputer facilities, education resource providers, information technology innovators, nonprofit organizations and commercial enterprises. The consortium's work is dedicated to providing the most up-to-date, science-based information to researchers and decision-makers who are working to understand and address the environmental, economic and social challenges facing our planet. By increasing the use and usability of Earth observation data and linking it with decision-making tools, the Federation partners leverage the value of these important data resources for the betterment of society and our planet. To further the dissemination of Earth Science data, the Federation is developing the Earth Information Exchange (EIE). The EIE is a portal that will provide access to the vast information holdings of the members' organizations in one web-based location and will provides a robust marketplace in which the products and services needed to use and understand this information can be readily acquired. Since the Federation membership includes the federal government's Earth observing data centers, we believe that the impact of the EIE on Earth science research and education and environmental policy making will be profound. In the EIE, Earth observation data, products and services, are organized by the societal benefits categories defined by the international working group developing the Global Earth Observation System of Systems (GEOSS). The quality of the information is ensured in each of the Exchange's issue areas by maintaining working groups of issue area researchers and practitioners who serve as stewards for their respective communities. The

  11. Catalyseur d'hydrocraquage à base de sulfure de NiMo déposé sur une zéolithe HEMT modifiée

    NASA Astrophysics Data System (ADS)

    Baalala, M.; Becue, T.; Leglise, J.; Manoli, J. M.; van Gestel, J. N. M.; Lamotte, J.; Bensitel, M.; Goupil, J. M.; Cornet, D.

    1999-02-01

    Treating a NH4EMT zeolite with a solution of (NH4)2SiF6 at 80 °C affords a solid containing amorphous SiO2 intimately mixed with the zeolite. This acidic support EMT-Si was loaded with NiMo sulfide in order to prepare a bifunctional catalyst, which was tested for the hydrogenation of benzene and the hydrocracking of n-heptane. This NiMo/EMT-Si catalyst was found more active for hydrogenation than the analogous NiMo/HY. This is ascribed to a higher dispersion of the NiMo sulfide, which is almost equally shared between the internal mesopores in the modified EMT solid, and the fissures, which were created throughout the zeolite grains upon inserting the NiMo sulfide. The catalyst with the EMT-Si support was also found more active than the NiMo/HY for the hydrocracking of heptane, with a slightly higher selectivity into heptane isomers. Le traitement d'une zéolithe NH4EMT par une solution de (NH4)2SiF6 fournit un solide comportant une phase SiO2 amorphe intimement mélangée aux parties intactes de la zéolithe. Sur ce support acide EMT-Si, on a greffé un sulfure de NiMo afin de préparer un catalyseur bifonctionnel qui a été testé dans les réactions d'hydrogénation du benzène et d'hydrocraquage du n-heptane. Ce catalyseur NiMo/EMT-Si s'avère plus actif en hydrogénation que son analogue NiMo/HY, en raison d'une meilleure dispersion du sulfure de NiMo. Sur le solide EMT modifié, le sulfure se répartit à peu près également entre les mésopores internes et les fissures crées dans les grains de zéolithe lors de l'insertion du sulfure de NiMo. Au contraire sur le support Y, une partie du sulfure est externe aux grains de zéolithe et inactive en catalyse. Le catalyseur NiMo/EMT-Si est aussi trouvé plus actif que le NiMo/HY en hydrocraquage du n-heptane, et un peu plus sélectif en isomères.

  12. Recycling of rare earth metals from rare earth-transition metal alloy scrap by liquid metal extraction

    DOEpatents

    Ellis, T.W.; Schmidt, F.A.

    1995-08-01

    A method is described for treating rare earth metal-bearing scrap, waste or other material (e.g. Nd--Fe--B or Dy--Tb--Fe scrap) to recover the rare earth metal comprising melting the rare earth metal-bearing material, melting a Group IIA metal extractant, such as Mg, Ca, or Ba, in which the rare earth is soluble in the molten state, and contacting the melted material and melted extractant at a temperature and for a time effective to extract the rare earth from the melted material into the melted extractant. The rare earth metal is separated from the extractant metal by vacuum sublimation or distillation. 2 figs.

  13. Earth before life.

    PubMed

    Marzban, Caren; Viswanathan, Raju; Yurtsever, Ulvi

    2014-01-09

    A recent study argued, based on data on functional genome size of major phyla, that there is evidence life may have originated significantly prior to the formation of the Earth. Here a more refined regression analysis is performed in which 1) measurement error is systematically taken into account, and 2) interval estimates (e.g., confidence or prediction intervals) are produced. It is shown that such models for which the interval estimate for the time origin of the genome includes the age of the Earth are consistent with observed data. The appearance of life after the formation of the Earth is consistent with the data set under examination.

  14. Development of an earth pressure model for design of earth retaining structures in piedmont soil.

    DOT National Transportation Integrated Search

    2008-10-01

    Anecdotal evidence suggests that earth pressure in Piedmont residual soils is typically over estimated. Such estimates of earth pressure impact the design of earth retaining structures used on highway projects. Thus, the development of an appropriate...

  15. The Earth's Core.

    ERIC Educational Resources Information Center

    Jeanloz, Raymond

    1983-01-01

    The nature of the earth's core is described. Indirect evidence (such as that determined from seismological data) indicates that it is an iron alloy, solid toward its center but otherwise liquid. Evidence also suggests that it is the turbulent flow of the liquid that generates the earth's magnetic field. (JN)

  16. Prise en charge d’un afflux massif de brûles lors d’une situation de catastrophe par incendie au Maroc

    PubMed Central

    Siah, S.; Hatimi, E.M.; Ihrai, H.; Drissi Kamili, N.

    2012-01-01

    Summary La brûlure est l’une des lésions les plus fréquemment rencontrées lors de catastrophes naturelles ou lors de catastrophes d’origine humaine (incendies de lieux publics d’origine accidentelle, ou en temps de guerre ou encore lors d’attentats terroristes). La prise en charge et le triage de brûlés en nombre reste un problème difficile; ceci souligne la nécessité d’une réflexion et de prévisions de ces crises en insistant sur la formation des médecins et des soignants. Les défis à relever sont multiples: les soins aux brûlés requièrent un nombre important de personnel qualifié; les évacuations doivent être planifiées en fonction de la gravité de la brûlure et des lésions associées; les stocks et lots de dotation (en particulier en topiques anti-infectieux et en cristalloïdes) doivent être suffisants et adéquats. Les services hospitaliers de l’Hôpital Militaire d’Instruction Mohammed V de Rabat doivent pouvoir être rapidement adaptés pour accueillir et surtout isoler ces patients. L’hypothèse d’une catastrophe par incendie avec afflux massif de brûlés à l’hôpital militaire d’instruction Mohammed V de Rabat ne doit laisser place à aucune improvisation. PMID:23467075

  17. Photoémission de Csl induite par une impulsion laser intense femtoseconde

    NASA Astrophysics Data System (ADS)

    Belsky, A.; Vasil'Ev, A.; Yatsenko, B.; Bachau, H.; Martin, P.; Geoffroy, G.; Guizard, S.

    2003-06-01

    Nous avons mesuré pour la première fois les spectres de photoélectrons émis par un cristal isolant à large bande interdite, Csl, avec une dynamique de 10^6 coups/s, excité par la source laser haute cadence du C.E.L.I.A (800 nm, 40 fs, 1 kHz, 1 TW). L'émission d'électrons jusqu'à des énergies de quelques dizaines d'électrons-volts a été observée pour des impulsions d'éclairement compris entre 0.5 et 3 TW/cm^2, relativement faible donc par comparaison aux éclairements utilisés pour accélérer les électrons d'un atome aux mêmes énergies. Ces spectres contiennent tous, en particulier, deux bandes dans le domaine des basses énergies d'électrons (<5 eV), également observées lors d'études précédentes. Les électrons les plus énergétiques forment un plateau intense légèrement structuré et limité par une coupure exponentielle. Pour des impulsions de 3 TW/cm^2 cette coupure est située à 27 eV. L'insuffisance du mécanisme électron-photon-phonon, considéré jusqu'à présent comme le principal processus d'échauffement des électrons dans les solides en interaction non destructrice avec un champ laser, nous a poussé à proposer un mécanisme alternatif. Ce modèle met en évidence les transitions directes multiphotoniques dans la bande de conduction du solide qui sont incontournables du fait de sa structure électronique multi-branches

  18. Earth Day at Union Station

    NASA Image and Video Library

    2013-04-22

    NASA's Earth Dome is seen at Union Station, Monday, April 22, 2013 in Washington. The Earth Dome housed two of NASA's Science Gallery exhibits as part of a NASA-sponsored Earth Day event at Union Station. Photo Credit: (NASA/Carla Cioffi)

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

    NASA Astrophysics Data System (ADS)

    Nicolas, Joëlle

    2000-12-01

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

  20. Appel pour une allocation intelligente dans le financement du système de santé au Cameroun

    PubMed Central

    Sieleunou, Isidore

    2011-01-01

    Le Cameroun utilise un système de budgétisation historique et une approche «top-down» pour allouer ses ressources de santé publique. Cependant, le pays compte 175 districts de santé dont les fortes disparités de nature épidémiologique, économique, géographique et culturelle, devraient être prises en compte pour réduire les iniquités en matière de sante publique. Comment comprendre alors que dans ces conditions, le budget des administrations publiques alloué aux différents districts de santé au Cameroun soit quasi identique alors que les défis sont si différents? L'inefficience allocative (mauvaise attribution du budget) générée par un tel système conduit vraisemblablement à une inefficience technique (mauvaise utilisation du budget). Pour la marche vers l'atteinte des objectifs du millénaire en matière de sante, il est impératif et urgent que les décideurs du secteur de la santé allouent de manière intelligente les ressources dans le système de santé. PMID:22355420

  1. Earth Observation

    NASA Image and Video Library

    2014-07-19

    ISS040-E-070424 (19 July 2014) --- One of the Expedition 40 crew members aboard the Earth-orbiting International Space Station recorded this July 19 image of wildfires which are plaguing the Northwest and causing widespread destruction. The orbital outpost was flying 223 nautical miles above Earth at the time of the photo. Lightning has been given as the cause of the Ochoco Complex fires in the Ochoco National Forest in central Oregon. The complex has gotten larger since this photo was taken.

  2. Une validation de la forme abrégée de l’Échelle de provisions sociales : l’ÉPS-10 items

    PubMed Central

    Caron, Jean

    2016-01-01

    L’Échelle de provisions sociales-10 items (ÉPS-10) est une version abrégée de l’Échelle de provisions sociales (Social Provisions Scale) (Cutrona et Russell, 1987) validée en langue française sur une population québécoise (Caron, 1996) et qui permet de mesurer la disponibilité du soutien social. L’ÉPS-10 conserve cinq des six sous-échelles de l’ÉPS (l’attachement ; l’intégration sociale ; la confirmation de sa valeur ; l’aide matérielle et l’orientation), le besoin de se sentir utile et nécessaire ayant été exclu, et ne garde que les items formulés positivement, soit deux items par dimension du soutien. L’article présente la validation de l’EPS-10 sur un échantillon représentatif de 2433 personnes provenant de la population générale du sud-ouest de Montréal. Elle a une forte validité concomitante avec l’Échelle originelle de 24 items (ÉPS). Tous ces items sont fortement corrélés au score total et sa consistance interne est excellente. Des analyses de corrélation entre les sous-échelles et le score global et une analyse factorielle indiquent que l’ÉPS-10 conserve sa validité de construit. L’ÉPS-10 explique 14,1 % de la variance de la détresse psychologique et 25,4 % de la variance de la qualité de vie et conserve un pouvoir prédictif équivalent à l’ÉPS à 24 items. L’ensemble des analyses suggère que l’ÉPS-10 est un instrument fiable et valide pour mesurer la disponibilité du soutien social avec un temps d’administration réduit de moitié. Il s’avère un excellent choix pour les enquêtes épidémiologiques. PMID:24337002

  3. Earth as art three

    USGS Publications Warehouse

    ,

    2010-01-01

    For most of us, deserts, mountains, river valleys, coastlines even dry lakebeds are relatively familiar features of the Earth's terrestrial environment. For earth scientists, they are the focus of considerable scientific research. Viewed from a unique and unconventional perspective, Earth's geographic attributes can also be a surprising source of awe-inspiring art. That unique perspective is space. The artists for the Earth as Art Three exhibit are the Landsat 5 and Landsat 7 satellites, which orbit approximately 705 kilometers (438 miles) above the Earth's surface. While studying the images these satellites beam down daily, researchers are often struck by the sheer beauty of the scenes. Such images inspire the imagination and go beyond scientific value to remind us how stunning, intricate, and simply amazing our planet's features can be. Instead of paint, the medium for these works of art is light. But Landsat satellite sensors don't see light as human eyes do; instead, they see radiant energy reflected from Earth's surface in certain wavelengths, or bands, of red, green, blue, and infrared light. When these different bands are combined into a single image, remarkable patterns, colors, and shapes emerge. The Earth as Art Three exhibit provides fresh and inspiring glimpses of different parts of our planet's complex surface. The images in this collection were chosen solely based on their aesthetic appeal. Many of the images have been manipulated to enhance color variations or details. They are not intended for scientific interpretation only for your viewing pleasure. Enjoy!

  4. Clementine Images of Earth and Moon

    NASA Technical Reports Server (NTRS)

    1997-01-01

    During its flight and lunar orbit, the Clementine spacecraft returned images of the planet Earth and the Moon. This collection of UVVIS camera Clementine images shows the Earth from the Moon and 3 images of the Earth.

    The image on the left shows the Earth as seen across the lunar north pole; the large crater in the foreground is Plaskett. The Earth actually appeared about twice as far above the lunar horizon as shown. The top right image shows the Earth as viewed by the UVVIS camera while Clementine was in transit to the Moon; swirling white cloud patterns indicate storms. The two views of southeastern Africa were acquired by the UVVIS camera while Clementine was in low Earth orbit early in the mission

  5. Habitability of the Paleo-Earth as a Model for Earth-like Exoplanets

    NASA Astrophysics Data System (ADS)

    Mendez, A.

    2013-05-01

    The Phanerozoic is the current eon of Earth's geological history, from 542 million years ago to today, when large and complex life started to populate the ocean and land areas. Our planet became more hospitable and life took the opportunity to evolve and spread globally, especially on land. This had an impact on surface and atmospheric bio-signatures. Future observations of exoplanets might be able to detect similar changes on nearby exoplanets. Therefore, the application of the evolution of terrestrial habitability might help to determine the potential for life on Earth-like exoplanets. Here we evaluated the habitability of Earth during the Phanerozoic as a model for comparison with future observations of Earth-like exoplanets. Vegetation was used as a global indicator of habitability because as a primary producer it provides the energy for many other simple to complex life forms in the trophic scale. Our first proxy for habitability was the Relative Vegetation Density (RVD) derived from our vegetation datasets of the Visible Paleo-Earth. The RVD is a measure similar to vegetation indices, such as the Normalized Difference Vegetation Index (NDVI), that gives a general idea of the global area-weighted fraction of vegetation cover. Our second habitability proxy was the Standard Primary Habitability (SPH) derived from mean global surface temperatures and relative humidity. The RVD is a more direct measure of the habitability of a planet but the SPH is easier to measure by remote sensors. Our analysis shows that terrestrial habitability has been greater than today for most of the Phanerozoic as demonstrated by both the RVD and SPH, with the Devonian and Cretaceous particularly more habitable. The RVD and SPH are generally correlated except around the Permian-Triassic, matching the P-Tr extinction. There has been a marked decrease in terrestrial habitability during the last 100 million years, even superseding the K-Pg extinction. Additional metrics were used to examine

  6. Paternité des articles et intérêts concurrents : une analyse des recommandations aux auteurs des journaux traitant de pratique pharmaceutique

    PubMed Central

    Courbon, Ève; Tanguay, Cynthia; Lebel, Denis; Bussières, Jean-François

    2014-01-01

    RÉSUMÉ Contexte : La présence d’auteurs honorifiques et fantômes ainsi que les intérêts concurrents représentent des difficultés bien documentées, liées à la publication d’articles scientifiques. Il existe des lignes directrices encadrant la rédaction et la publication de manuscrits scientifiques, notamment celles de l’International Committee of Medical Journal Editors (ICMJE). Objectifs : L’objectif principal de cette étude descriptive et transversale visait à recenser les instructions portant sur la paternité des articles et les intérêts concurrents provenant des recommandations aux auteurs des journaux traitant de pratique pharmaceutique. L’objectif secondaire visait à déterminer des mesures correctrices pour une paternité des articles plus transparente. Méthode : La recherche a débuté par l’identification des journaux traitant de pratique pharmaceutique. La consultation des instructions aux auteurs des journaux a permis ensuite de recenser les recommandations destinées à éviter les problèmes de paternité des articles et d’intérêts concurrents. Finalement, les membres de l’équipe de recherche se sont consultés afin de définir des mesures correctrices possibles à l’intention des chercheurs. Résultats : Des 232 journaux traitant de pharmacie, 33 ont été définis comme traitant de pratique pharmaceutique. Un total de 24 (73 %) journaux mentionnaient suivre la politique de l’ICMJE, 14 (42 %) demandaient aux auteurs de remplir un formulaire de déclaration d’intérêts concurrents au moment de la soumission de l’article, 17 (52 %) présentaient une définition de la qualité d’auteur et 5 (15 %) demandaient de détailler les contributions de chaque auteur. Une grille de 40 critères a été élaborée pour définir l’attribution du statut d’auteur. Conclusion : Moins de la moitié des journaux demandait aux auteurs de transmettre un formulaire de déclaration des intérêts concurrents au moment de la

  7. Mouvements collectifs de grandes amplitudes dans les noyaux : une approche microscopique

    NASA Astrophysics Data System (ADS)

    Giannoni, M.-J.

    Various aspects of the adiabatic limit of the time-dependent Hartree-Fock approximation are studied. This formalism is a mean field theory for nuclear collective motion which provides microscopical foundations to the successful phenomenological collective models, and whose validity is not restricted to small amplitude phenomena. Emphasis is put on the classical Hamiltonian-like structure of the dynamical equations. Several limiting cases of the general formalism are considered : Random Phase Approximation, Nuclear Hydrodynamics, case of a single collective variable. Applications to low-lying vibrational modes are described. Results are discussed in terms of sum rules. A quantitative comparison between self-consistent and Inglis cranking mass parameters is made. Important dynamical corrections to the Hartree-Fock ground state are expected for soft nuclei. On étudie divers aspects de l'approximation de Hartree-Fock dépendant du temps à la limite adiabatique. Ce formalisme est une théorie de champ moyen adaptée à la description de phénomènes collectifs dans les noyaux, et dont le domaine de validité n'est pas limité aux mouvements de faibles amplitudes ; d'autre part il permet, grâce à l'approximation adiabatique, de comprendre en termes microscopiques les modèles collectifs purement phénoménologiques. La structure Hamiltonienne classique des équations de mouvement, est étudiée en détail. On considère plusieurs cas limites du formalisme général : approximation des phases au hasard (RPA), limite hydrodynamique, réduction à une seule variable collective. Dans le cadre de ce dernier cas limite, on calcule les paramètres de masse pour les modes vibrationnels quadrupolaires de plusieurs noyaux. Les résultats sont discutés en termes de règle de somme. On compare les paramètres de masse autocohérents aux paramètres de masse d'Inglis. Le formalisme conduit à d'importantes corrections, d'origine dynamique, à l'état fondamental de Hartree

  8. PREFACE: The 2nd International Conference on Geological, Geographical, Aerospace and Earth Sciences 2014 (AeroEarth 2014)

    NASA Astrophysics Data System (ADS)

    Lumban Gaol, Ford; Soewito, Benfano

    2015-01-01

    The 2nd International Conference on Geological, Geographical, Aerospace and Earth Sciences 2014 (AeroEarth 2014), was held at Discovery Kartika Plaza Hotel, Kuta, Bali, Indonesia during 11 - 12 October 2014. The AeroEarth 2014 conference aims to bring together researchers and engineers from around the world. Through research and development, earth scientists have the power to preserve the planet's different resource domains by providing expert opinion and information about the forces which make life possible on Earth. Earth provides resources and the exact conditions to make life possible. However, with the advent of technology and industrialization, the Earth's resources are being pushed to the brink of depletion. Non-sustainable industrial practices are not only endangering the supply of the Earth's natural resources, but are also putting burden on life itself by bringing about pollution and climate change. A major role of earth science scholars is to examine the delicate balance between the Earth's resources and the growing demands of industrialization. Through research and development, earth scientists have the power to preserve the planet's different resource domains by providing expert opinion and information about the forces which make life possible on Earth. We would like to express our sincere gratitude to all in the Technical Program Committee who have reviewed the papers and developed a very interesting Conference Program as well as the invited and plenary speakers. This year, we received 98 papers and after rigorous review, 17 papers were accepted. The participants come from eight countries. There are four Parallel Sessions and two invited Speakers. It is an honour to present this volume of IOP Conference Series: Earth and Environmental Science (EES) and we deeply thank the authors for their enthusiastic and high-grade contributions. Finally, we would like to thank the conference chairmen, the members of the steering committee, the organizing committee

  9. Earth Science: Then and Now

    ERIC Educational Resources Information Center

    Orgren, James R.

    1969-01-01

    Reviews history of earth science in secondary schools. From early nineteenth century to the present, earth science (and its antecedents, geology, physical geography, and astronomy) has had an erratic history for several reasons, but particularly because of lack of earth science teacher-training programs. (BR)

  10. COMPASS Final Report: Near Earth Asteroids Rendezvous and Sample Earth Returns (NEARER)

    NASA Technical Reports Server (NTRS)

    Oleson, Steven R.; McGuire, Melissa L.

    2009-01-01

    In this study, the Collaborative Modeling for Parametric Assessment of Space Systems (COMPASS) team completed a design for a multi-asteroid (Nereus and 1996 FG3) sample return capable spacecraft for the NASA In-Space Propulsion Office. The objective of the study was to support technology development and assess the relative benefits of different electric propulsion systems on asteroid sample return design. The design uses a single, heritage Orion solar array (SA) (approx.6.5 kW at 1 AU) to power a single NASA Evolutionary Xenon Thruster ((NEXT) a spare NEXT is carried) to propel a lander to two near Earth asteroids. After landing and gathering science samples, the Solar Electric Propulsion (SEP) vehicle spirals back to Earth where it drops off the first sample s return capsule and performs an Earth flyby to assist the craft in rendezvousing with a second asteroid, which is then sampled. The second sample is returned in a similar fashion. The vehicle, dubbed Near Earth Asteroids Rendezvous and Sample Earth Returns (NEARER), easily fits in an Atlas 401 launcher and its cost estimates put the mission in the New Frontier s (NF's) class mission.

  11. Google Earth Engine

    NASA Astrophysics Data System (ADS)

    Gorelick, Noel

    2013-04-01

    The Google Earth Engine platform is a system designed to enable petabyte-scale, scientific analysis and visualization of geospatial datasets. Earth Engine provides a consolidated environment including a massive data catalog co-located with thousands of computers for analysis. The user-friendly front-end provides a workbench environment to allow interactive data and algorithm development and exploration and provides a convenient mechanism for scientists to share data, visualizations and analytic algorithms via URLs. The Earth Engine data catalog contains a wide variety of popular, curated datasets, including the world's largest online collection of Landsat scenes (> 2.0M), numerous MODIS collections, and many vector-based data sets. The platform provides a uniform access mechanism to a variety of data types, independent of their bands, projection, bit-depth, resolution, etc..., facilitating easy multi-sensor analysis. Additionally, a user is able to add and curate their own data and collections. Using a just-in-time, distributed computation model, Earth Engine can rapidly process enormous quantities of geo-spatial data. All computation is performed lazily; nothing is computed until it's required either for output or as input to another step. This model allows real-time feedback and preview during algorithm development, supporting a rapid algorithm development, test, and improvement cycle that scales seamlessly to large-scale production data processing. Through integration with a variety of other services, Earth Engine is able to bring to bear considerable analytic and technical firepower in a transparent fashion, including: AI-based classification via integration with Google's machine learning infrastructure, publishing and distribution at Google scale through integration with the Google Maps API, Maps Engine and Google Earth, and support for in-the-field activities such as validation, ground-truthing, crowd-sourcing and citizen science though the Android Open Data

  12. Google Earth Engine

    NASA Astrophysics Data System (ADS)

    Gorelick, N.

    2012-12-01

    The Google Earth Engine platform is a system designed to enable petabyte-scale, scientific analysis and visualization of geospatial datasets. Earth Engine provides a consolidated environment including a massive data catalog co-located with thousands of computers for analysis. The user-friendly front-end provides a workbench environment to allow interactive data and algorithm development and exploration and provides a convenient mechanism for scientists to share data, visualizations and analytic algorithms via URLs. The Earth Engine data catalog contains a wide variety of popular, curated datasets, including the world's largest online collection of Landsat scenes (> 2.0M), numerous MODIS collections, and many vector-based data sets. The platform provides a uniform access mechanism to a variety of data types, independent of their bands, projection, bit-depth, resolution, etc..., facilitating easy multi-sensor analysis. Additionally, a user is able to add and curate their own data and collections. Using a just-in-time, distributed computation model, Earth Engine can rapidly process enormous quantities of geo-spatial data. All computation is performed lazily; nothing is computed until it's required either for output or as input to another step. This model allows real-time feedback and preview during algorithm development, supporting a rapid algorithm development, test, and improvement cycle that scales seamlessly to large-scale production data processing. Through integration with a variety of other services, Earth Engine is able to bring to bear considerable analytic and technical firepower in a transparent fashion, including: AI-based classification via integration with Google's machine learning infrastructure, publishing and distribution at Google scale through integration with the Google Maps API, Maps Engine and Google Earth, and support for in-the-field activities such as validation, ground-truthing, crowd-sourcing and citizen science though the Android Open Data

  13. Earth radiation balance and climate: Why the Moon is the wrong place to observe the Earth

    NASA Astrophysics Data System (ADS)

    Kandel, Robert S.

    1994-06-01

    Increasing 'greenhouse' gases in the Earth's atmosphere will perturb the Earth's radiation balance, forcing climate change over coming decades. Climate sensitivity depends critically on cloud-radiation feedback: its evaluation requires continual observation of changing patterns of Earth radiation balance and cloud cover. The Moon is the wrong place for such observations, with many disadvantages compared to an observation system combining platforms in low polar, intermediate-inclination and geostationary orbits. From the Moon, active observations are infeasible; thermal infrared observations require very large instruments to reach spatial resolutions obtained at much lower cost from geostationary or lower orbits. The Earth's polar zones are never well observed from the Moon; other zones are invisible more than half the time. The monthly illumination cycle leads to further bias in radiation budget determinations. The Earth will be a pretty sight from the Earth-side of the Moon, but serious Earth observations will be made elsewhere.

  14. Earth Science Enterprise Technology Strategy

    NASA Technical Reports Server (NTRS)

    1999-01-01

    NASA's Earth Science Enterprise (ESE) is dedicated to understanding the total Earth system and the effects of natural and human-induced changes on the global environment. The goals of ESE are: (1) Expand scientific knowledge of the Earth system using NASA's unique vantage points of space, aircraft, and in situ platforms; (2) Disseminate information about the Earth system; and (3) Enable the productive use of ESE science and technology in the public and private sectors. ESE has embraced the NASA Administrator's better, faster, cheaper paradigm for Earth observing missions. We are committed to launch the next generation of Earth Observing System (EOS) missions at a substantially lower cost than the EOS first series. Strategic investment in advanced instrument, spacecraft, and information system technologies is essential to accomplishing ESE's research goals in the coming decades. Advanced technology will play a major role in shaping the ESE fundamental and applied research program of the future. ESE has established an Earth science technology development program with the following objectives: (1) To accomplish ESE space-based and land-based program elements effectively and efficiently; and (2) To enable ESE's fundamental and applied research programs goals as stated in the NASA Strategic Plan.

  15. A volatile rich Earth's core?

    NASA Astrophysics Data System (ADS)

    Morard, G.; Antonangeli, D.; Andrault, D.; Nakajima, Y.

    2017-12-01

    The composition of the Earth's core is still an open question. Although mostly composed of iron, it contains impurities that lower its density and melting point with respect to pure Fe. Knowledge of the nature and abundance of light elements (O, S, Si, C or H) in the core has major implications for establishing the bulk composition of the Earth and for building the model of Earth's differentiation. Geochemical models of the Earth's formation point out that its building blocks were depleted in volatile elements compared to the chondritic abundance, therefore light elements such as S, H or C cannot be the major elements alloyed with iron in the Earth's core. However, such models should be compatible with the comparison of seismic properties of the Earth's core and physical properties of iron alloys under extreme conditions, such as sound velocity or density of solid and liquid. The present work will discuss the recent progress for compositional model issued from studies of phase diagrams and elastic properties of iron alloys under core conditions and highlight the compatibility of volatile elements with observed properties of the Earth's core, in potential contradiction with models derived from metal-silicate partitioning experiments.

  16. Using EarthLabs to Enhance Earth Science Curriculum in Texas

    NASA Astrophysics Data System (ADS)

    Chegwidden, D. M.; Ellins, K. K.; Haddad, N.; Ledley, T. S.

    2012-12-01

    As an educator in Texas, a state that values and supports an Earth Science curriculum, I find it essential to educate my students who are our future voting citizens and tax payers. It is important to equip them with tools to understand and solve the challenges of solving of climate change. As informed citizens, students can help to educate others in the community with basic knowledge of weather and climate. They can also help to dispose of the many misconceptions that surround the climate change, which is perceived as a controversial topic. As a participant in a NSF-sponsored Texas Earth and Space (TXESS) Revolution teacher professional development program, I was selected to participate in a curriculum development project led by TERC to develop and test education resources for the EarthLabs climate literacy collection. I am involved in the multiple phases of the project, including reviewing labs that comprise the Climate, Weather and Biosphere module during the development phase, pilot teaching the module with my students, participating in research, and delivering professional development to other Texas teachers to expose them to the content found in the module and to encourage them to incorporate it into their teaching. The Climate, Weather and the Biosphere module emphasizes different forms of evidence and requires that learners apply different inquiry-based approaches to build the knowledge they need to develop as climate literate citizens. My involvement with the EarthLabs project has strengthened my overall knowledge and confidence to teach about Earth's climate system and climate change. In addition, the project has produced vigorous classroom discussion among my students as well as encouraged me to collaborate with other educators through our delivery of professional development to other teachers. In my poster, I will share my experiences, describe the impact the curriculum has made on my students, and report on challenges and valuable lessons gained by

  17. Lightcurve Analysis for Two Near-Earth Asteroids Eclipsed by the Earth's Shadow

    NASA Astrophysics Data System (ADS)

    Birtwhistle, Peter

    2018-07-01

    Photometry was obtained from Great Shefford Observatory of near-Earth asteroids 2012 XE54 in 2012 and 2016 VA in 2016 during close approaches. A superfast rotation period has been determined for 2012 XE54 and H-G magnitude system coefficients have been estimated for 2016 VA. While under observation, 2012 XE54 underwent a deep penumbral eclipse by the Earth's shadow and 2016 VA also experienced a total eclipse by the Earth's shadow. The dimming due to the eclipses is modeled taking into account solar limb darkening.

  18. Mission to Planet Earth

    NASA Technical Reports Server (NTRS)

    Wilson, Gregory S.; Huntress, Wesley T.

    1990-01-01

    The rationale behind Mission to Planet Earth is presented, and the program plan is described in detail. NASA and its interagency and international partners will place satellites carrying advanced sensors in strategic earth orbits to collect muultidisciplinary data. A sophisticated data system will process and archive an unprecedented large amount of information about the earth and how it functions as a system. Attention is given to the space observatories, the data and information systems, and the interdisciplinary research.

  19. The Earth is a Planet Too!

    NASA Technical Reports Server (NTRS)

    Cairns, Brian

    2014-01-01

    When the solar system formed, the sun was 30 dimmer than today and Venus had an ocean. As the sun brightened, a runaway greenhouse effect caused the Venus ocean to boil away. At times when Earth was younger, the sun less bright, and atmospheric CO2 less, Earth froze over (snowball Earth). Earth is in the sweet spot today. Venus is closer to sun than Earth is, but cloud-covered Venus absorbs only 25 of incident sunlight, while Earth absorbs 70. Venus is warmer because it has a thick carbon dioxide atmosphere causing a greenhouse effect of several hundred degrees. Earth is Goldilocks choice among the planets, the one that is just right for life to exist. Not too hot. Not too cold. How does the Earth manage to stay in this habitable range? Is there a Gaia phenomenon keeping the climate in bounds? A nice idea, but it doesnt work. Today, greenhouse gas levels are unprecedented compared to the last 450,000 years.

  20. Diagnostics différentiels d'images d'hypofixations sur une scintigraphie du squelette: à propos d'un cas de leucémie aigue lymphoblastique

    PubMed Central

    Bahadi, Nisrine; Biyi, Abdelhamid; Oueriagli, Salah Nabih; Doudouh, Abderrahim

    2016-01-01

    Si les hyperfixations sont la traduction scintigraphique habituelle de nombreuses pathologies osseuses, les hypofixations sont un événement rare et suscitent souvent analyse minutieuse afin d’éviter des interprétations erronés. Nous rapportons ici l'observation d'un adolescent de 17 ans admis pour douleurs osseuses diffuses, une hypercalcémie et une thrombopénie. La scintigraphie du squelette a montré des foyers d'hypofixations. L’étude de la moelle osseuse a conclu au diagnostic de leucémie aigue lymphoblastique. A travers ce cas clinique, nous discutons les principaux diagnostics différentiels soulevés par de telles anomalies scintigraphiques. PMID:27642484

  1. Earth

    NASA Image and Video Library

    2012-01-30

    Behold one of the more detailed images of the Earth yet created. This Blue Marble Earth montage shown above -- created from photographs taken by the Visible/Infrared Imager Radiometer Suite (VIIRS) instrument on board the new Suomi NPP satellite -- shows many stunning details of our home planet. The Suomi NPP satellite was launched last October and renamed last week after Verner Suomi, commonly deemed the father of satellite meteorology. The composite was created from the data collected during four orbits of the robotic satellite taken earlier this month and digitally projected onto the globe. Many features of North America and the Western Hemisphere are particularly visible on a high resolution version of the image. http://photojournal.jpl.nasa.gov/catalog/PIA18033

  2. The EarthLabs Approach to Curriculum and Professional Development: Earth Science Education in the 21st Century

    NASA Astrophysics Data System (ADS)

    Mote, A. S.; Ellins, K. K.; Haddad, N.

    2011-12-01

    Humans are modifying planet Earth at an alarming rate without fully understanding how our actions will affect the atmosphere, hydrosphere, or biosphere. Recognizing the value of educating people to become citizens who can make informed decisions about Earth's resources and challenges, Texas currently offers Earth and Space Science as a rigorous high school capstone course. The new course has created a need for high quality instructional resources and professional development to equip teachers with the most up to date content knowledge, pedagogical approaches, and technological skills to be able to teach a rigorous Earth and Space Science course. As a participant in the NSF-sponsored Texas Earth and Space Science (TXESS) Revolution teacher professional development program, I was selected to participate in a curriculum development project led by TERC to create Earth System Science and climate change resources for the EarthLabs collection. To this end, I am involved in multiple phases of the EarthLabs project, including reviewing the lab-based units during the development phase, pilot teaching the units with my students, participating in research, and ultimately delivering professional development to other teachers to turn them on to the new modules. My partnership with the EarthLabs project has strengthened my teaching practice by increasing my involvement with curriculum development and collaboration and interaction with other Earth science educators. Critically evaluating the lab modules prior to delivering the lessons to my students has prepared me to more effectively teach the EarthLabs modules in my classroom and present the material to other teachers during professional development workshops. The workshop was also strengthened by planning meetings held with EarthLabs partner teachers in which we engaged in lively discussions regarding misconceptions in Earth science, held by both students and adults, and pedagogical approaches to uncover these misconceptions

  3. The Earth System Model

    NASA Technical Reports Server (NTRS)

    Schoeberl, Mark; Rood, Richard B.; Hildebrand, Peter; Raymond, Carol

    2003-01-01

    The Earth System Model is the natural evolution of current climate models and will be the ultimate embodiment of our geophysical understanding of the planet. These models are constructed from components - atmosphere, ocean, ice, land, chemistry, solid earth, etc. models and merged together through a coupling program which is responsible for the exchange of data from the components. Climate models and future earth system models will have standardized modules, and these standards are now being developed by the ESMF project funded by NASA. The Earth System Model will have a variety of uses beyond climate prediction. The model can be used to build climate data records making it the core of an assimilation system, and it can be used in OSSE experiments to evaluate. The computing and storage requirements for the ESM appear to be daunting. However, the Japanese ES theoretical computing capability is already within 20% of the minimum requirements needed for some 2010 climate model applications. Thus it seems very possible that a focused effort to build an Earth System Model will achieve succcss.

  4. Clementine Images of Earth and Moon

    NASA Image and Video Library

    1999-06-12

    During its flight and lunar orbit, NASA’s Clementine spacecraft returned images of the planet Earth and the Moon. This collection of UVVIS camera Clementine images shows the Earth from the Moon and 3 images of the Earth. The image on the left shows the Earth as seen across the lunar north pole; the large crater in the foreground is Plaskett. The Earth actually appeared about twice as far above the lunar horizon as shown. The top right image shows the Earth as viewed by the UVVIS camera while Clementine was in transit to the Moon; swirling white cloud patterns indicate storms. The two views of southeastern Africa were acquired by the UVVIS camera while Clementine was in low Earth orbit early in the mission. http://photojournal.jpl.nasa.gov/catalog/PIA00432

  5. The Earth Charter

    ERIC Educational Resources Information Center

    Journal of Education for Sustainable Development, 2010

    2010-01-01

    Humanity is part of a vast evolving universe. Earth is alive with a unique community of life. The forces of nature make existence a demanding and uncertain adventure, but Earth has provided the conditions essential to life's evolution. The resilience of the community of life and the well-being of humanity depend upon preserving a healthy biosphere…

  6. Analysis of Risks in a Learning Management System: A Case Study in the Spanish National University of Distance Education (UNED)

    ERIC Educational Resources Information Center

    Vázquez-Cano, Esteban; Sevillano García, Ma. Luisa

    2015-01-01

    This article presents a research that examines the university students' risk perception when using a Learning Management System called "aLF" and implemented by the Spanish National University of Distance Education (UNED) for the development of its university distance studies. The development of comprehensive Learning Management Systems…

  7. From Earth Algebra to Earth Math: An Expansion and Dissemination of the Methods of Earth Algebra [and] Proceedings, Earth Math Conference (Kennesaw, Georgia, April 19-20, 1996).

    ERIC Educational Resources Information Center

    Zumoff, Nancy; Schaufele, Christopher

    This final report and appended conference proceedings describe activities of the Earth Math project, a 3-year effort at Kennesaw State University (Georgia) to broaden and disseminate the concept of Earth Algebra to precalculus and mathematics education courses. Major outcomes of the project were the draft of a precalculus textbook now being…

  8. Google Earth locations of USA and seafloor hydrothermal vents with associated rare earth element data

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

    Andrew Fowler

    Google Earth .kmz files that contain the locations of geothermal wells and thermal springs in the USA, and seafloor hydrothermal vents that have associated rare earth element data. The file does not contain the actual data, the actual data is available through the GDR website in two tier 3 data sets entitled "Compilation of Rare Earth Element Analyses from US Geothermal Fields and Mid Ocean Ridge (MOR) Hydrothermal Vents" and "Rare earth element content of thermal fluids from Surprise Valley, California"

  9. Ames Lab 101: Rare Earths

    ScienceCinema

    Gschneidner, Karl

    2017-12-11

    "Mr. Rare Earth," Ames Laboratory scientist Karl Gschneidner Jr., explains the importance of rare-earth materials in many of the technologies we use today -- ranging from computers to hybrid cars to wind turbines. Gschneidner is a world renowned rare-earths expert at the U.S. Department of Energy's Ames Laboratory.

  10. 47 CFR 97.209 - Earth station.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 47 Telecommunication 5 2013-10-01 2013-10-01 false Earth station. 97.209 Section 97.209... SERVICE Special Operations § 97.209 Earth station. (a) Any amateur station may be an Earth station. A holder of any class operator license may be the control operator of an Earth station, subject to the...

  11. 47 CFR 97.209 - Earth station.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 47 Telecommunication 5 2011-10-01 2011-10-01 false Earth station. 97.209 Section 97.209... SERVICE Special Operations § 97.209 Earth station. (a) Any amateur station may be an Earth station. A holder of any class operator license may be the control operator of an Earth station, subject to the...

  12. 47 CFR 97.209 - Earth station.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 47 Telecommunication 5 2012-10-01 2012-10-01 false Earth station. 97.209 Section 97.209... SERVICE Special Operations § 97.209 Earth station. (a) Any amateur station may be an Earth station. A holder of any class operator license may be the control operator of an Earth station, subject to the...

  13. 47 CFR 97.209 - Earth station.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 5 2010-10-01 2010-10-01 false Earth station. 97.209 Section 97.209... SERVICE Special Operations § 97.209 Earth station. (a) Any amateur station may be an Earth station. A holder of any class operator license may be the control operator of an Earth station, subject to the...

  14. 47 CFR 97.209 - Earth station.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 47 Telecommunication 5 2014-10-01 2014-10-01 false Earth station. 97.209 Section 97.209... SERVICE Special Operations § 97.209 Earth station. (a) Any amateur station may be an Earth station. A holder of any class operator license may be the control operator of an Earth station, subject to the...

  15. Earth Radiation Measurement Science

    NASA Technical Reports Server (NTRS)

    Smith, G. Louis

    2000-01-01

    This document is the final report for NASA Grant NAG1-1959, 'Earth Radiation Measurement Science'. The purpose of this grant was to perform research in this area for the needs of the Clouds and Earth Radiant Energy System (CERES) project and for the Earth Radiation Budget Experiment (ERBE), which are bing conducted by the Radiation and Aerosols Branch of the Atmospheric Sciences Division of Langley Research Center. Earth Radiation Measurement Science investigates the processes by which measurements are converted into data products. Under this grant, research was to be conducted for five tasks: (1) Point Response Function Measurements; (2) Temporal Sampling of Outgoing Longwave Radiation; (3) Spatial Averaging of Radiation Budget Data; (4) CERES Data Validation and Applications; and (5) ScaRaB Data Validation and Application.

  16. Diagnostic tardif d'une hyperoxalurie primitive au stade d'insuffisance rénale chronique terminale avec hypoparathyroïdie sévère

    PubMed Central

    El Ghali, Zineb; Lahcen, Zineb Ait; Fadili, Wafaa; Kaitouni, Abderrahim Idrissi; Hakkou, Mohamed; Hamdaoui, Abderrachid; Laouad, Inass

    2014-01-01

    L'hyperoxalurie primitive est une anomalie métabolique congénitale rare caractérisée par un excès de production avec accumulation d'oxalate secondaire à un déficit enzymatique hépatique. Nous rapportons le cas d'un patient de 18 ans qui avait comme antécédent des lithiases rénales récidivantes depuis l'enfance évoluant vers l'insuffisance rénale chronique terminale, mis en hémodialyse périodique depuis 4 ans avec apparition d'une anémie résistante à l’érythropoïétine pour laquelle il a été multitransfusé et qui était admis pour prise en charge de douleurs osseuses invalidantes d'aggravation progressive associées à un syndrome tumoral fait d'adénopathies périphériques et de splénomégalie avec dyspnée et altération de l’état général. Le bilan réalisé avait objectivé de multiples images lytiques lacunaires et condensantes au niveau des poignets et des mains avec des petits reins calcifiés, une pleurésie avec péricardite de grande abondance drainée, une ascite de moyenne abondance avec splénomégalie homogène, une anémie normochrome normocytaire à 7.2 g/dl avec hyperferritinémie à 1129 μg/l et un syndrome inflammatoire biologique. La calcémie était spontanément normale à 97 mg/l avec hyperphosphorémie à 83 mg/l et hypoparathyroïdie à 74,85 pg/ml. Les PAL étaient à 136 UI/l, l'aluminium sérique à 13μg/l et la Vitamine D native à 20,87ng/ml. Le diagnostic d'hyperoxalurie a été retenu sur les données de la biopsie ostéomédullaire objectivant des dépôts de cristaux d'oxalate de calcium avec fibrose médullaire et réaction macrophagique à corps étranger. L’évolution a été marquée par la survenue de fractures spontanées récidivantes au niveau de l’épaule et des 2 hanches. PMID:25328593

  17. Principes et réalisation d'une chaîne laser femtoseconde haute intensité basée sur le saphir dopé au titane

    NASA Astrophysics Data System (ADS)

    Le Blanc, Catherine

    We present the initial study, the realisation and the characterisation of a high intensity femtosecond laser chain. This chain is able to produce intensities higher than 10^18 W/cm2 on target, at a 10 Hertz repetition rate. We present first fondamentals principles of chirped pulse propagation mechanisms: group velocity dispersion, self-phase modulation, self-focusing, and gain saturation. Then after describing the spectroscopic properties of titanium doped sapphire (Ti:S), we discuss near infrared femtosecond oscillators able to be amplified in Ti:S medium, and describe our home made Kerr Lens mode locked femtosecond Ti:S oscillator. The high intensity laser chain is based on the Chirped Pulse Amplification concept, which consists in stretching the pulse before its amplification in order to avoid non-linear effects such self-focusing or breakdown, and then recompressing it to its initial pulse duration. We have developed two compact and efficient multipass amplifiers for femtosecond chirped pulse amplification. With only two of these devices, we obtain an amplification factor of 10^8, which corresponds to a peak power of ˜ 0.5 terawatt after compression. We analyse in details the performances of this system and its advantages in terms of its high quantum yield (0.3), flexibility, and optical quality. Some observed spectral distortion on chirped pulses is simply explained by a gain saturation model. High dynamic pulse temporal control is crucial for interaction experiments. For this reason, we have developed a third order sampling autocorrelator. This device is able to measure 100 fs pulses with more than 8 orders of magnitude. I compare our obtained performances to other femtosecond systems and I analyse the best way to increase the energy, reduce the pulse duration and optimise focusing in order to reach the 10^19 W/cm2 regime. Ce mémoire présente les études préliminaires, la réalisation et la caractérisation d'une chaîne dite "de haute intensité" en r

  18. Earth Education: A New Beginning.

    ERIC Educational Resources Information Center

    Van Matre, Steve

    The Institute for Earth Education is a nonprofit volunteer group made up of an international network of individuals and member organizations devoted to helping people live more lightly on the earth. This book proposes an alternative path to solve environmental problems. The program, called the earth education path, seeks to accomplish one of…

  19. Cool Earth Solar

    ScienceCinema

    Lamkin, Rob; McIlroy, Andy; Swalwell, Eric; Rajan,

    2018-05-30

    In a public-private partnership that takes full advantage of the Livermore Valley Open Campus (LVOC) for the first time, Sandia National Laboratories and Cool Earth Solar have signed an agreement that could make solar energy more affordable and accessible. In this piece, representatives from Sandia, Cool Earth Solar, and leaders in California government all discuss the unique partnership and its expected impact.

  20. NASA Earth Day 2014

    NASA Image and Video Library

    2014-04-22

    Students listen intently while NASA's Director, Earth Science Division, Mike Freilich, speaks at NASA's Earth Day event. The event took place at Union Station in Washington, DC on April 22, 2014. Photo Credit: (NASA/Aubrey Gemignani)

  1. Raman scattering of rare earth hexaborides

    NASA Astrophysics Data System (ADS)

    Ogita, Norio; Hasegawa, Takumi; Udagawa, Masayuki; Iga, Fumitoshi; Kunii, Satoru

    2009-06-01

    Raman scattering spectra were measured for the rare-earth hexaborides RB6 (R = Ce, Gd, or Dy). All Raman-active phonons due to B6 vibrations were observed in the range 600 - 1400 cm-1. Anomalous peaks were detected below 200 cm-1, which correspond to vibrations of rare-earth ion excited by second-order Raman scattering process. The intensity and energy of the rare-earth mode decrease with decreasing temperature. This suggests that the rare-earth ion vibrates in a shallow and anharmonic potential due to the boron cage. Using the reported values of mean square displacement of rare-earth ion, we estimated the anharmonic contribution for the rare-earth vibrations.

  2. CERES Detects Earth's Heat and Energy

    NASA Technical Reports Server (NTRS)

    2002-01-01

    Clouds and the Earth's Radiant Energy System, CERES, monitors solar energy reflected from the Earth and heat energy emitted from the Earth. In this image, heat energy radiated from the earth is shown in varying shades of yellow, red, blue and white. The brightest yellow areas, such as the Sahara Desert and Arabian Peninsula, are emitting the most energy out to space, while the dark blue polar regions and bright white clouds are the coldest areas on Earth, and are emitting the least energy. The animation (1.5MB) (high-res (4MB)) shows roughly a week of CERES data. For more information: CERES images through Visible Earth. CERES web site Image courtesy of the CERES instrument team

  3. The Earth's Plasmasphere

    NASA Technical Reports Server (NTRS)

    Gallagher, D. L.

    2015-01-01

    The Earth's plasmasphere is an inner part of the magneteosphere. It is located just outside the upper ionosphere located in Earth's atmosphere. It is a region of dense, cold plasma that surrounds the Earth. Although plasma is found throughout the magnetosphere, the plasmasphere usually contains the coldest plasma. Here's how it works: The upper reaches of our planet's atmosphere are exposed to ultraviolet light from the Sun, and they are ionized with electrons that are freed from neutral atmospheric particles. The results are electrically charged negative and positive particles. The negative particles are electrons, and the positive particles are now called ions (formerly atoms and molecules). If the density of these particles is low enough, this electrically charged gas behaves differently than it would if it were neutral. Now this gas is called plasma. The atmospheric gas density becomes low enough to support the conditions for a plasma around earth at about 90 kilometers above Earth's surface. The electrons in plasma gain more energy, and they are very low in mass. They move along Earth's magnetic field lines and their increased energy is enough to escape Earth's gravity. Because electrons are very light, they don't have to gain too much kinetic energy from the Sun's ultraviolet light before gravity loses its grip on them. Gravity is not all that holds them back, however. As more and more electrons begin to escape outward, they leave behind a growing net positive electric charge in the ionosphere and create a growing net negative electric charge above the ionosphere; an electric field begins to develop (the Pannekoek-Rosseland E-field). Thus, these different interacting charges result in a positively charged ionosphere and negatively charged region of space above it. Very quickly this resulting electric field opposed upward movement of the electrons out of the ionosphere. The electrons still have this increased energy, however, so the electric field doesn't just

  4. Earth Science Applications Showcase

    NASA Image and Video Library

    2014-08-05

    Michael Gao presents his project on Southeast Asian disasters during the annual DEVELOP Earth Science Application Showcase at NASA headquarters Tuesday, August 5, 2014. The Earth Science Applications Showcase highlights the work of over 150 participants in the 10-week DEVELOP program that started in June. The DEVELOP Program bridges the gap between NASA Earth science and society, building capacity in both its participants and partner organizations, to better prepare them to handle the challenges that face our society and future generations. Photo Credit: (NASA/Aubrey Gemignani)

  5. Intrinsic Hydrophobicity of Rammed Earth

    NASA Astrophysics Data System (ADS)

    Holub, M.; Stone, C.; Balintova, M.; Grul, R.

    2015-11-01

    Rammed earth is well known for its vapour diffusion properties, its ability to regulate humidity within the built environment. Rammed earth is also an aesthetically iconic material such as marble or granite and therefore is preferably left exposed. However exposed rammed earth is often coated with silane/siloxane water repellents or the structure is modified architecturally (large roof overhangs) to accommodate for the hydrophilic nature of the material. This paper sets out to find out optimal hydrophobicity for rammed earth based on natural composite fibres and surface coating without adversely affecting the vapour diffusivity of the material. The material is not required to be waterproof, but should resist at least driving rain. In order to evaluate different approaches to increase hydrophobicity of rammed earth surface, peat fibres and four types of repellents were used.

  6. Earth Day at Union Station

    NASA Image and Video Library

    2013-04-22

    Jennifer Brennan, NASA EOSDIS Outreach Lead at NASA's Goddard Spaceflight Center, speaks to participants at a NASA Earth Day sponsored exhibit about satellite earth imagery, Monday, April 22, 2013 at Union Station in Washington. The NASA Science Gallery exhibits are being sponsored by NASA in honor of Earth Day. (Photo Credit: NASA/Carla Cioffi)

  7. Earth - India and Australia

    NASA Image and Video Library

    1996-02-08

    This color image of the Earth was obtained by NASA’s Galileo spacecraft on Dec. 11, 1990, when the spacecraft was about 1.5 million miles from the Earth. http://photojournal.jpl.nasa.gov/catalog/PIA00122

  8. Oblique Shot of Earth

    NASA Image and Video Library

    2008-09-05

    This highly oblique image shot over northwestern part of the African continent captures the curvature of the Earth and shows its atmosphere as seen by NASA EarthKAM. You can see clouds and even the occasional thunderhead.

  9. Production method for making rare earth compounds

    DOEpatents

    McCallum, R.W.; Ellis, T.W.; Dennis, K.W.; Hofer, R.J.; Branagan, D.J.

    1997-11-25

    A method of making a rare earth compound, such as a earth-transition metal permanent magnet compound, without the need for producing rare earth metal as a process step, comprises carbothermically reacting a rare earth oxide to form a rare earth carbide and heating the rare earth carbide, a compound-forming reactant (e.g., a transition metal and optional boron), and a carbide-forming element (e.g., a refractory metal) that forms a carbide that is more thermodynamically favorable than the rare earth carbide whereby the rare earth compound (e.g., Nd{sub 2}Fe{sub 14}B or LaNi{sub 5}) and a carbide of the carbide-forming element are formed.

  10. Production method for making rare earth compounds

    DOEpatents

    McCallum, R. William; Ellis, Timothy W.; Dennis, Kevin W.; Hofer, Robert J.; Branagan, Daniel J.

    1997-11-25

    A method of making a rare earth compound, such as a earth-transition metal permanent magnet compound, without the need for producing rare earth metal as a process step, comprises carbothermically reacting a rare earth oxide to form a rare earth carbide and heating the rare earth carbide, a compound-forming reactant (e.g. a transition metal and optional boron), and a carbide-forming element (e.g. a refractory metal) that forms a carbide that is more thermodynamically favorable than the rare earth carbide whereby the rare earth compound (e.g. Nd.sub.2 Fe.sub.14 B or LaNi.sub.5) and a carbide of the carbide-forming element are formed.

  11. Factors Affecting Student Success with a Google Earth-Based Earth Science Curriculum

    ERIC Educational Resources Information Center

    Blank, Lisa M.; Almquist, Heather; Estrada, Jen; Crews, Jeff

    2016-01-01

    This study investigated to what extent the implementation of a Google Earth (GE)-based earth science curriculum increased students' understanding of volcanoes, earthquakes, plate tectonics, scientific reasoning abilities, and science identity. Nine science classrooms participated in the study. In eight of the classrooms, pre- and post-assessments…

  12. Unique Non-Keplerian Orbit Vantage Locations for Sun-Earth Connection and Earth Science Vision Roadmaps

    NASA Technical Reports Server (NTRS)

    Folta, David; Young, Corissa; Ross, Adam

    2001-01-01

    The purpose of this investigation is to determine the feasibility of attaining and maintaining unique non-Keplerian orbit vantage locations in the Earth/Moon environment in order to obtain continuous scientific measurements. The principal difficulty associated with obtaining continuous measurements is the temporal nature of astrodynamics, i.e., classical orbits. This investigation demonstrates advanced trajectory designs to meet demanding science requirements which cannot be met following traditional orbital mechanic logic. Examples of continuous observer missions addressed include Earth pole-sitters and unique vertical libration orbits that address Sun-Earth Connection and Earth Science Vision roadmaps.

  13. The early Earth Observing System reference handbook: Earth Science and Applications Division missions, 1990-1997

    NASA Technical Reports Server (NTRS)

    1990-01-01

    Prior to the launch of the Earth Observing System (EOS) series, NASA will launch and operate a wide variety of new earth science satellites and instruments, as well as undertake several efforts collecting and using the data from existing and planned satellites from other agencies and nations. These initiatives will augment the knowledge base gained from ongoing Earth Science and Applications Division (ESAD) programs. This volume describes three sets of ESAD activities -- ongoing exploitation of operational satellite data, research missions with upcoming launches between now and the first launch of EOS, and candidate earth probes.

  14. Earth Rings for Planetary Environment Control

    NASA Astrophysics Data System (ADS)

    Pearson, Jerome; Oldson, John; Levin, Eugene; Carroll, Joseph

    2002-01-01

    For most of its past, large parts of the Earth have experienced subtropical climates, with high sea levels and no polar icecaps. This warmer environment was punctuated 570, 280, and 3 million years ago with periods of glaciation that covered temperate regions with thick ice for millions of years. At the end of the current ice age, a warmer climate could flood coastal cities, even without human-caused global warming. In addition, asteroids bombard the Earth periodically, with impacts large enough to destroy most life on Earth, and the sun is warming inexorably. This paper proposes a concept to solve these problems simultaneously, by creating an artificial planetary ring about the Earth to shade it. Past proposals for space climate control have depended on gigantic engineering structures launched from Earth and placed in Earth orbit or at the Earth-Sun L1 libration point, requiring fabrication, large launch masses and expense, constant control, and repair. Our solution is to begin by using lunar material, and then mine and remove Earth-orbit-crossing asteroids and discard the tailings into Earth orbit, to form a broad, flat ring like those of Saturn. This solution is evaluated and compared with other alternatives. Such ring systems can persist for thousands of years, and can be maintained by shepherding satellites or by continual replenishment from new asteroids to replace the edges of the ring lost by diffusion. An Earth ring at R = 1.3-1.83 RE would shade only the equatorial regions, moderating climate extremes, and could reverse a century of global warming. It could also absorb particles from the radiation belts, making trips to high Earth orbit and GEO safer for humans and for electronics. It would also light the night many times as bright as the full moon. A preliminary design of the ring is developed, including its location, mass, composition, stability, and timescale required. A one-dimensional climate model is used to evaluate the Earth ring performance

  15. Répercussions psychosociales de la drépanocytose sur les parents d'enfants vivant à Kinshasa, République Démocratique du Congo: une étude qualitative

    PubMed Central

    Luboya, Evariste; Tshilonda, Jean-Christophe Bukasa; Ekila, Mathilde Bothale; Aloni, Michel Ntetani

    2014-01-01

    Introduction L'insuffisance des moyens de base pour le dépistage et la prise en charge de la socioculturel Africain. D'où la nécessité de réaliser un travail de mise en sens du vécu et des émotions en vue d'information et de soutien psychologique des familles des drépanocytaires. Cette étude a eu pour objectif d'identifier la nature des répercussions psychosociales de la drépanocytose chez les parents et chez les malades. Méthodes Une approche qualitative a été utilisée. Des entretiens ont été menés auprès des parents et des patients drépanocytaires. Nos résultats ont fait l'objet d'une analyse thématique articulée sur les circonstances de découvertes de la maladie, les répercussions de la maladie et la perception de la prise en charge. Résultats Nos interviews ont montré des répercussions psychosociales importantes chez les parents d'enfants drépanocytaires et de stigmatisation des difficultés d'insertion sociale et scolaire pour les enfants drépanocytaires. Ces derniers sont les grands oubliés des récits de parents. La prise en charge est uniquement médicale avec des ressources très limitées et aucun accompagnement psychologique de la famille n'est assuré. Conclusion La prise en charge de cette maladie nécessite la mise en place d'une politique de prise en charge basée sur une approche globale de la maladie. PMID:25574334

  16. Guided earth boring tool

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

    Mc Donald, W.J.; Pittard, G.T.; Maurer, W.C.

    A controllable tool for drilling holes in the earth is described comprising a hollow elongated rigid supporting drill pipe having a forward end for entering the earth, means supporting the drill pipe for earth boring or piercing movement, including means for moving the drill pipe longitudinally for penetrating the earth, the drill pipe moving means being constructed to permit addition and removal of supporting drill pipe during earth penetrating operation, a boring mole supported on the forward end of the hollow low drill pipe comprising a cylindrical housing supported on and open to the forward end of the drill pipe,more » a first means on the front end for applying a boring force to the soil comprising an anvil having a striking surface inside the housing and a boring surface outside the housing, a second means comprising a reciprocally movable hammer positioned in the housing to apply a percussive force to the anvil striking surface for transmitting a percussive force to the boring force applying means, and means permitting introduction of air pressure supplied through the hollow pipe into the housing for operating the hammer and for discharging spent air from the housing to the hole being bored, and the tool being operable to penetrate the earth upon longitudinal movement of the drill rod by the longitudinal rod moving means and operation of the mole by reciprocal movement of the hammer.« less

  17. Crescent Earth and Moon

    NASA Technical Reports Server (NTRS)

    1977-01-01

    This picture of a crescent-shaped Earth and Moon -- the first of its kind ever taken by a spacecraft -- was recorded Sept. 18, 1977, by NASA's Voyager 1 when it was 7.25 million miles (11.66 million kilometers) from Earth. The Moon is at the top of the picture and beyond the Earth as viewed by Voyager. In the picture are eastern Asia, the western Pacific Ocean and part of the Arctic. Voyager 1 was directly above Mt. Everest (on the night side of the planet at 25 degrees north latitude) when the picture was taken. The photo was made from three images taken through color filters, then processed by the Jet Propulsion Laboratory's Image Processing Lab. Because the Earth is many times brighter than the Moon, the Moon was artificially brightened by a factor of three relative to the Earth by computer enhancement so that both bodies would show clearly in the print. Voyager 2 was launched Aug. 20, 1977, followed by Voyager 1 on Sept. 5, 1977, en route to encounters at Jupiter in 1979 and Saturn in 1980 and 1981. JPL manages the Voyager mission for NASA's Office of Space Science.

  18. Décision d'amputation dans la prise en charge initiale d'une luxation ouverte grave de la cheville à propos d'un cas observé à l'Hôpital Laquintinie de Douala suite à un accident par moto-taxi

    PubMed Central

    Tsatedem, Faustin Atemkeng; Tsiagadigui, Jean Gustave; Ndando, Richard Polle; Arabo, Mohamadou Saidou; Bayiha, Alphonse; Kenfack, Bruno

    2012-01-01

    La décision d'amputation pour traumatisme grave de membre n'est pas toujours facile à prendre. Les auteurs rapportent le cas d'un traumatisme ouvert de la cheville gauche avec luxation tibiotalienne complète, référé pour amputation. Il s'agit d'une passagère d'une moto-taxi percutée par une voiture. A l'admission, le pouls tibial postérieur était présent et le score dit MESS (Mangled Extremity Severity Score) côté à 5, ce qui a permis et d'éviter l'amputation. Après débridement et réduction, une broche transplantaire a permis d'immobiliser la cheville et de faire les pansements. L'amputation a été évitée. La cicatrisation dirigée de la peau a été suivie par la kinésithérapie. La mobilité de la cheville autorise une marche avec cannes au quatrième mois post-opératoire. Les auteurs recommandent l'utilisation du MESS dans la décision d'amputation après traumatisme grave de membre. PMID:23396997

  19. Earth-approaching asteroid streams

    NASA Astrophysics Data System (ADS)

    Drummond, J. D.

    1991-01-01

    Three association patterns have been noted among 139 earth-approaching asteroids on the basis of current orbital similarity; these asteroid streams, consisting of two groups of five members and one of four, can be matched to three of the four meteorite-producing fireball streams determined by Halliday et al. (1990). If the asteroid streams are true nonrandom associations, the opportunity arises for studies of an 'exploded' asteroid in the near-earth environment. Near-earth asteroid-search projects are encouraged to search the mean orbit of the present streams in order to discover additional association members.

  20. Earth Science Applications Showcase

    NASA Image and Video Library

    2014-08-05

    NASA Administrator Charles Bolden speaks with young professionals about their project during the annual DEVELOP Earth Science Application Showcase at NASA headquarters Tuesday, August 5, 2014. The Earth Science Applications Showcase highlights the work of over 150 participants in the 10-week DEVELOP program that started in June. The DEVELOP Program bridges the gap between NASA Earth science and society, building capacity in both its participants and partner organizations, to better prepare them to handle the challenges that face our society and future generations. Photo Credit: (NASA/Aubrey Gemignani)

  1. Earth Science Applications Showcase

    NASA Image and Video Library

    2014-08-05

    NASA Administrator Charles Bolden poses for a selfie after a quick rap performance by some young professionals during the annual DEVELOP Earth Science Application Showcase at NASA headquarters Tuesday, August 5, 2014. The Earth Science Applications Showcase highlights the work of over 150 participants in the 10-week DEVELOP program that started in June. The DEVELOP Program bridges the gap between NASA Earth science and society, building capacity in both its participants and partner organizations, to better prepare them to handle the challenges that face our society and future generations. Photo Credit: (NASA/Aubrey Gemignani)

  2. Earth Science Applications Showcase

    NASA Image and Video Library

    2014-08-05

    NASA Administrator Charles Bolden speaks with young professionals about their project on New England water resources during the annual DEVELOP Earth Science Application Showcase at NASA headquarters Tuesday, August 5, 2014. The Earth Science Applications Showcase highlights the work of over 150 participants in the 10-week DEVELOP program that started in June. The DEVELOP Program bridges the gap between NASA Earth science and society, building capacity in both its participants and partner organizations, to better prepare them to handle the challenges that face our society and future generations. Photo Credit: (NASA/Aubrey Gemignani)

  3. Earth Science Applications Showcase

    NASA Image and Video Library

    2014-08-05

    Lisa Waldron and Justin Roberts-Pierel present their project on Texas health and air quality during the annual DEVELOP Earth Science Application Showcase at NASA headquarters Tuesday, August 5, 2014. The Earth Science Applications Showcase highlights the work of over 150 participants in the 10-week DEVELOP program that started in June. The DEVELOP Program bridges the gap between NASA Earth science and society, building capacity in both its participants and partner organizations, to better prepare them to handle the challenges that face our society and future generations. Photo Credit: (NASA/Aubrey Gemignani)

  4. Earth Science Applications Showcase

    NASA Image and Video Library

    2014-08-05

    NASA Administrator Charles Bolden asks young professionals about their projects after posing for a group photo during the annual DEVELOP Earth Science Application Showcase at NASA headquarters Tuesday, August 5, 2014. The Earth Science Applications Showcase highlights the work of over 150 participants in the 10-week DEVELOP program that started in June. The DEVELOP Program bridges the gap between NASA Earth science and society, building capacity in both its participants and partner organizations, to better prepare them to handle the challenges that face our society and future generations. Photo Credit: (NASA/Aubrey Gemignani)

  5. Earth Orientation Help - Naval Oceanography Portal

    Science.gov Websites

    section Advanced Search... Sections Home Time Earth Orientation Astronomy Meteorology Oceanography Ice You are here: Home › Help › Earth Orientation Help USNO Logo USNO Info Earth Orientation Help Send an e-mail regarding Earth Orientation products. Privacy Advisory Your E-Mail Address Subject ■ Select

  6. What can earth tide measurements tell us about ocean tides or earth structure?

    NASA Technical Reports Server (NTRS)

    Baker, T. F.

    1978-01-01

    Current experimental problems in Earth tides are reviewed using comparisons of tidal gravity and tilt measurements in Europe with loading calculations are examples. The limitations of present day instrumentation and installation techniques are shown as well as some of the ways in which they can be improved. Many of the geophysical and oceanographic investigations that are possible with Earth tide measurements are discussed with emphasis on the percentage accuracies required in the measurements in order to obtain new information about Earth or its oceans.

  7. ATLAS 1: Encountering Planet Earth

    NASA Technical Reports Server (NTRS)

    Shea, Charlotte; Mcmahan, Tracy; Accardi, Denise; Tygielski, Michele; Mikatarian, Jeff; Wiginton, Margaret (Editor)

    1984-01-01

    Several NASA science programs examine the dynamic balance of sunlight, atmosphere, water, land, and life that governs Earth's environment. Among these is a series of Space Shuttle-Spacelab missions, named the Atmospheric Laboratory for Applications and Science (ATLAS). During the ATLAS missions, international teams of scientists representing many disciplines combine their expertise to seek answers to complex questions about the atmospheric and solar conditions that sustain life on Earth. The ATLAS program specifically investigates how Earth's middle atmosphere and upper atmospheres and climate are affected by both the Sun and by products of industrial and agricultural activities on Earth.

  8. Ecology of Near-Earth Space

    NASA Astrophysics Data System (ADS)

    Nikoghosyan, E. H.

    2017-12-01

    The technical achievements of our civilization are accompanied by certain negative consequences affect the near-Earth space. The problem of clogging of near-Earth space by "space debris" as purely theoretical arose essentially as soon as the first artificial satellite in 1957 was launched. Since then, the rate of exploitation of outer space has increased very rapidly. As a result, the problem of clogging of near-Earth space ceased to be only theoretical and transformed into practical. Presently, anthropogenic factors of the development of near-Earth space are divided into several categories: mechanical, chemical, radioactive and electromagnetic pollution.

  9. Visualizing Earth Materials

    NASA Astrophysics Data System (ADS)

    Cashman, K. V.; Rust, A.; Stibbon, E.; Harris, R.

    2016-12-01

    Earth materials are fundamental to art. They are pigments, they are clay, they provide form and color. Earth scientists, however, rarely attempt to make the physical properties of Earth materials visible through art, and similarly many artists use Earth materials without fully understanding their physical and chemical properties. Here we explore the intersection between art and science through study of the physical properties of Earth materials as characterized in the laboratory, and as transferred to paper using different techniques and suspending media. One focus of this collaboration is volcanic ash. Ash is interesting scientifically because its form provides information on the fundamental processes that drive volcanic eruptions, and determines its transport properties, and thus its potential to affect populations far downwind of the volcano. Ash properties also affect its behavior as an art material. From an aesthetic point of view, ash lends a granular surface to the image; it is also uncontrollable, and thus requires engagement between artist and medium. More fundamentally, using ash in art creates an exchange between the medium and the subject matter, and imparts something of the physical, visceral experience of volcanic landscapes to the viewer. Another component of this work uses powdered rock as a printing medium for geologic maps. Because different types of rock create powders with different properties (grain size distributions and shapes), the geology is communicated not only as color, but also by the physical characteristics of the material as it interacts with the paper. More importantly, the use of actual rocks samples as printing material for geologic maps not only makes a direct connection between the map and the material it represents, but also provides an emotional connection between the map, the viewer and the landscape, its colors, textures and geological juxtapositions. Both case studies provide examples not only of ways in which artists can

  10. Phase stable rare earth garnets

    DOEpatents

    Kuntz, Joshua D.; Cherepy, Nerine J.; Roberts, Jeffery J.; Payne, Stephen A.

    2013-06-11

    A transparent ceramic according to one embodiment includes a rare earth garnet comprising A.sub.hB.sub.iC.sub.jO.sub.12, where h is 3.+-.10%, i is 2.+-.10%, and j is 3.+-.10%. A includes a rare earth element or a mixture of rare earth elements, B includes at least one of aluminum, gallium and scandium, and C includes at least one of aluminum, gallium and scandium, where A is at a dodecahedral site of the garnet, B is at an octahedral site of the garnet, and C is at a tetrahedral site of the garnet. In one embodiment, the rare earth garment has scintillation properties. A radiation detector in one embodiment includes a transparent ceramic as described above and a photo detector optically coupled to the rare earth garnet.

  11. Earth on the Move.

    ERIC Educational Resources Information Center

    Naturescope, 1987

    1987-01-01

    Provides background information on the layers of the earth, the relationship between changes on the surface of the earth and its insides, and plate tectonics. Teaching activities are included, with some containing reproducible worksheets and handouts to accompany them. (TW)

  12. Earth Observation

    NASA Image and Video Library

    2014-07-19

    ISS040-E-070412 (19 July 2014) --- One of the Expedition 40 crew members aboard the Earth-orbiting International Space Station recorded this July 19 panorama featuring wildfires which are plaguing the Northwest and causing widespread destruction. (Note: south is at the top of the frame). The orbital outpost was flying 223 nautical miles above Earth at the time of the photo. Parts of Oregon and Washington are included in the scene. Mt. Jefferson, Three Sisters and Mt. St. Helens are all snow-capped and visible in the photo, and the Columbia River can also be delineated.

  13. Earth observation

    NASA Image and Video Library

    2014-09-04

    ISS040-E-129950 (4 Sept. 2014) --- In this photograph. taken by one of the Expedition 40 crew members aboard the Earth-orbiting International Space Station, the orange spot located in the very center is the sun, which appears to be sitting on Earth's limb. At far right, a small bright spot is believed to be a reflection from somewhere in the camera system or something on the orbital outpost. When the photographed was exposed, the orbital outpost was flying at an altutude of 226 nautical miles above a point near French Polynesia in the Pacific Ocean.

  14. Earth Science

    NASA Image and Video Library

    2004-08-13

    This panoramic view of Hurricane Charley was photographed by the Expedition 9 crew aboard the International Space Station (ISS) on August 13, 2004, at a vantage point just north of Tampa, Florida. The small eye was not visible in this view, but the raised cloud tops near the center coincide roughly with the time that the storm began to rapidly strengthen. The category 2 hurricane was moving north-northwest at 18 mph packing winds of 105 mph. Crew Earth Observations record Earth surface changes over time, as well as more fleeting events such as storms, floods, fires, and volcanic eruptions.

  15. Earth Science

    NASA Image and Video Library

    2004-09-11

    This image hosts a look at the eye of Hurricane Ivan, one of the strongest hurricanes on record, as the storm topped the western Caribbean Sea on Saturday, September 11, 2004. The hurricane was photographed by astronaut Edward M. (Mike) Fincke from aboard the International Space Station (ISS) at an altitude of approximately 230 miles. At the time, the category 5 storm sustained winds in the eye of the wall that were reported at about 160 mph. Crew Earth Observations record Earth surface changes over time, as well as more fleeting events such as storms, floods, fires, and volcanic eruptions.

  16. Assessing the Impact of Earth Radiation Pressure Acceleration on Low-Earth Orbit Satellites

    NASA Astrophysics Data System (ADS)

    Vielberg, Kristin; Forootan, Ehsan; Lück, Christina; Kusche, Jürgen; Börger, Klaus

    2017-04-01

    The orbits of satellites are influenced by several external forces. The main non-gravitational forces besides thermospheric drag, acting on the surface of satellites, are accelerations due to the Earth and Solar Radiation Pres- sure (SRP and ERP, respectively). The sun radiates visible and infrared light reaching the satellite directly, which causes the SRP. Earth also emits and reflects the sunlight back into space, where it acts on satellites. This is known as ERP acceleration. The influence of ERP increases with decreasing distance to the Earth, and for low-earth orbit (LEO) satellites ERP must be taken into account in orbit and gravity computations. Estimating acceler- ations requires knowledge about energy emitted from the Earth, which can be derived from satellite remote sensing data, and also by considering the shape and surface material of a satellite. In this sensitivity study, we assess ERP accelerations based on different input albedo and emission fields and their modelling for the satellite missions Challenging Mini-Satellite Payload (CHAMP) and Gravity Recovery and Climate Experiment (GRACE). As input fields, monthly 1°x1° products of Clouds and the Earth's Radiant En- ergy System (CERES), L3 are considered. Albedo and emission models are generated as latitude-dependent, as well as in terms of spherical harmonics. The impact of different albedo and emission models as well as the macro model and the altitude of satellites on ERP accelerations will be discussed.

  17. Determination of thorium and of rare earth elements in cerium earth minerals and ores

    USGS Publications Warehouse

    Carron, M.K.; Skinner, D.L.; Stevens, R.E.

    1955-01-01

    The conventional oxalate method for precipitating thorium and the rare earth elements in acid solution exhibits definite solubilities of these elements. The present work was undertaken to establish conditions overcoming these solubilities and to find optimum conditions for precipitating thorium and the rare earth elements as hydroxides and sebacates. The investigations resulted in a reliable procedure applicable to samples in which the cerium group elements predominate. The oxalate precipitations are made from homogeneous solution at pH 2 by adding a prepared solution of anhydrous oxalic acid in methanol instead of the more expensive crystalline methyl oxalate. Calcium is added as a carrier. Quantitative precipitation of thorium and the rare earth elements is ascertained by further small additions of calcium to the supernatant liquid, until the added calcium precipitates as oxalate within 2 minutes. Calcium is removed by precipitating the hydroxides of thorium and rare earths at room temperature by adding ammonium hydroxide to pH > 10. Thorium is separated as the sebacate at pH 2.5, and the rare earths are precipitated with ammonium sebacate at pH 9. Maximum errors for combined weights of thorium and rare earth oxides on synthetic mixtures are ??0.6 mg. Maximum error for separated thoria is ??0.5 mg.

  18. HABEBEE: habitability of eyeball-exo-Earths.

    PubMed

    Angerhausen, Daniel; Sapers, Haley; Citron, Robert; Bergantini, Alexandre; Lutz, Stefanie; Queiroz, Luciano Lopes; da Rosa Alexandre, Marcelo; Araujo, Ana Carolina Vieira

    2013-03-01

    Extrasolar Earth and super-Earth planets orbiting within the habitable zone of M dwarf host stars may play a significant role in the discovery of habitable environments beyond Earth. Spectroscopic characterization of these exoplanets with respect to habitability requires the determination of habitability parameters with respect to remote sensing. The habitable zone of dwarf stars is located in close proximity to the host star, such that exoplanets orbiting within this zone will likely be tidally locked. On terrestrial planets with an icy shell, this may produce a liquid water ocean at the substellar point, one particular "Eyeball Earth" state. In this research proposal, HABEBEE: exploring the HABitability of Eyeball-Exo-Earths, we define the parameters necessary to achieve a stable icy Eyeball Earth capable of supporting life. Astronomical and geochemical research will define parameters needed to simulate potentially habitable environments on an icy Eyeball Earth planet. Biological requirements will be based on detailed studies of microbial communities within Earth analog environments. Using the interdisciplinary results of both the physical and biological teams, we will set up a simulation chamber to expose a cold- and UV-tolerant microbial community to the theoretically derived Eyeball Earth climate states, simulating the composition, atmosphere, physical parameters, and stellar irradiation. Combining the results of both studies will enable us to derive observable parameters as well as target decision guidance and feasibility analysis for upcoming astronomical platforms.

  19. Pull vs. Push: How OmniEarth Delivers Better Earth Observation Information to Subscribers

    NASA Astrophysics Data System (ADS)

    Fish, C.; Slagowski, S.; Dyrud, L.; Fentzke, J.; Hargis, B.; Steerman, M.

    2015-04-01

    Until very recently, the commercialization of Earth observation systems has largely occurred in two ways: either through the detuning of government satellites or the repurposing of NASA (or other science) data for commercial use. However, the convergence of cloud computing and low-cost satellites is enabling Earth observation companies to tailor observation data to specific markets. Now, underserved constituencies, such as agriculture and energy, can tap into Earth observation data that is provided at a cadence, resolution and cost that can have a real impact to their bottom line. To connect with these markets, OmniEarth fuses data from a variety of sources, synthesizes it into useful and valuable business information, and delivers it to customers via web or mobile interfaces. The "secret sauce" is no longer about having the highest resolution imagery, but rather it is about using that imagery - in conjunction with a number of other sources - to solve complex problems that require timely and contextual information about our dynamic and changing planet. OmniEarth improves subscribers' ability to visualize the world around them by enhancing their ability to see, analyze, and react to change in real time through a solutions-as-a-service platform.

  20. Connecting Earth Systems: Developing Holistic Understanding through the Earth-System-Science Model

    ERIC Educational Resources Information Center

    Gagnon, Valoree; Bradway, Heather

    2012-01-01

    For many years, Earth science concepts have been taught as thematic units with lessons in nice, neat chapter packages complete with labs and notes. But compartmentalized Earth science no longer exists, and implementing teaching methods that support student development of holistic understandings can be a time-consuming and difficult task. While…

  1. Conception, elaboration et mise a l'essai d'un simulateur interactif permettant une approche modelisante: Application aux lois de la genetique mendelienne

    NASA Astrophysics Data System (ADS)

    Lasri, Abdel-Halim

    Dans cette recherche-developpement, nous avons concu, developpe et mis a l'essai un simulateur interactif pour favoriser l'apprentissage des lois probabilistes impliqees dans la genetique mendelienne. Cet environnement informatise devra permettre aux etudiants de mener des experiences simulees, utilisant les statistiques et les probebilites comme outils mathematiques pour modeliser le phenomene de la transmission des caracteres hereditaires. L'approche didactique est essentiellement orientee vers l'utilisation des methodes quantitatives impliquees dans l'experimentation des facteurs hereditaires. En incorporant au simulateur le principe de la "Lunette cognitive" de Nonnon (1986), l'etudiant fut place dans une situation ou il a pu synchroniser la perception de la representation iconique (concrete) et symbolique (abstraite) des lois probabilistes de Mendel. A l'aide de cet environnement, nous avons amene l'etudiant a identifier le(s) caractere(s) hereditaire(s) des parents a croiser, a predire les frequences phenotypiques probables de la descendance issue du croisement, a observer les resultats statistiques et leur fluctuation au niveau de l'histogramme des frequences, a comparer ces resultats aux predictions anticipees, a interpreter les donnees et a selectionner en consequence d'autres experiences a realiser. Les etapes de l'approche inductive sont privilegiees du debut a la fin des activites proposees. L'elaboration, du simulateur et des documents d'accompagnement, a ete concue a partir d'une vingtaine de principes directeurs et d'un modele d'action. Ces principes directeurs et le modele d'action decoulent de considerations theoriques psychologiques, didactiques et technologiques. La recherche decrit la structure des differentes parties composant le simulateur. L'architecture de celui-ci est construite autour d'une unite centrale, la "Principale", dont les liens et les ramifications avec les autres unites confere a l'ensemble du simulateur sa souplesse et sa

  2. Selective Emitter Pumped Rare Earth Laser

    NASA Technical Reports Server (NTRS)

    Chubb, Donald L. (Inventor); Patton, Martin O. (Inventor)

    2001-01-01

    A selective emitter pumped rare earth laser provides an additional type of laser for use in many laser applications. Rare earth doped lasers exist which are pumped with flashtubes or laser diodes. The invention uses a rare earth emitter to transform thermal energy input to a spectral band matching the absorption band of a rare earth in the laser in order to produce lasing.

  3. Earthing the human body influences physiologic processes.

    PubMed

    Sokal, Karol; Sokal, Pawel

    2011-04-01

    This study was designed to answer the question: Does the contact of the human organism with the Earth via a copper conductor affect physiologic processes? Subjects and experiments: Five (5) experiments are presented: experiment 1-effect of earthing on calcium-phosphate homeostasis and serum concentrations of iron (N = 84 participants); experiment 2-effect of earthing on serum concentrations of electrolytes (N = 28); experiment 3-effect of earthing on thyroid function (N = 12); experiment 4-effect of earthing on glucose concentration (N = 12); experiment 5-effect of earthing on immune response to vaccine (N = 32). Subjects were divided into two groups. One (1) group of people was earthed, while the second group remained without contact with the Earth. Blood and urine samples were examined. Earthing of an electrically insulated human organism during night rest causes lowering of serum concentrations of iron, ionized calcium, inorganic phosphorus, and reduction of renal excretion of calcium and phosphorus. Earthing during night rest decreases free tri-iodothyronine and increases free thyroxine and thyroid-stimulating hormone. The continuous earthing of the human body decreases blood glucose in patients with diabetes. Earthing decreases sodium, potassium, magnesium, iron, total protein, and albumin concentrations while the levels of transferrin, ferritin, and globulins α1, α2, β, and γ increase. These results are statistically significant. Earthing the human body influences human physiologic processes. This influence is observed during night relaxation and during physical activity. Effect of the earthing on calcium-phosphate homeostasis is the opposite of that which occurs in states of weightlessness. It also increases the activity of catabolic processes. It may be the primary factor regulating endocrine and nervous systems.

  4. The Australian Computational Earth Systems Simulator

    NASA Astrophysics Data System (ADS)

    Mora, P.; Muhlhaus, H.; Lister, G.; Dyskin, A.; Place, D.; Appelbe, B.; Nimmervoll, N.; Abramson, D.

    2001-12-01

    Numerical simulation of the physics and dynamics of the entire earth system offers an outstanding opportunity for advancing earth system science and technology but represents a major challenge due to the range of scales and physical processes involved, as well as the magnitude of the software engineering effort required. However, new simulation and computer technologies are bringing this objective within reach. Under a special competitive national funding scheme to establish new Major National Research Facilities (MNRF), the Australian government together with a consortium of Universities and research institutions have funded construction of the Australian Computational Earth Systems Simulator (ACcESS). The Simulator or computational virtual earth will provide the research infrastructure to the Australian earth systems science community required for simulations of dynamical earth processes at scales ranging from microscopic to global. It will consist of thematic supercomputer infrastructure and an earth systems simulation software system. The Simulator models and software will be constructed over a five year period by a multi-disciplinary team of computational scientists, mathematicians, earth scientists, civil engineers and software engineers. The construction team will integrate numerical simulation models (3D discrete elements/lattice solid model, particle-in-cell large deformation finite-element method, stress reconstruction models, multi-scale continuum models etc) with geophysical, geological and tectonic models, through advanced software engineering and visualization technologies. When fully constructed, the Simulator aims to provide the software and hardware infrastructure needed to model solid earth phenomena including global scale dynamics and mineralisation processes, crustal scale processes including plate tectonics, mountain building, interacting fault system dynamics, and micro-scale processes that control the geological, physical and dynamic

  5. Earth observing system: 1989 reference handbook

    NASA Technical Reports Server (NTRS)

    1989-01-01

    NASA is studying a coordinated effort called the Mission to Planet Earth to understand global change. The goals are to understand the Earth as a system, and to determine those processes that contribute to the environmental balance, as well as those that may result in changes. The Earth Observing System (Eos) is the centerpiece of the program. Eos will create an integrated scientific observing system that will enable multidisciplinary study of the Earth including the atmosphere, oceans, land surface, polar regions, and solid Earth. Science goals, the Eos data and information system, experiments, measuring instruments, and interdisciplinary investigations are described.

  6. Patterns in Crew-Initiated Photography of Earth from ISS - Is Earth Observation a Salutogenic Experience?

    NASA Technical Reports Server (NTRS)

    Robinson, Julie A.; Slack, Kelley; Olson, V.; Trenchard, M.; Willis, K.; Baskin, P.

    2006-01-01

    This viewgraph presentation asks the question "Is the observation of earth from the ISS a positive (salutogenic) experience for crew members?"All images are distributed to the public via the "Gateway to Astronaut Photography of Earth at http://eol.jsc.nasa.gov. The objectives of the study are (1) Mine the dataset of Earth Observation photography--What can it tell us about the importance of viewing the Earth as a positive experience for the crewmembers? (2) Quantify extent to which photography was self-initiated (not requested by scientists) (3) Identify patterns photography activities versus scientific requested photography.

  7. NASA Earth Day 2014

    NASA Image and Video Library

    2014-04-22

    An attendee of NASA's Earth Day event observes the glow from a bracelet that is part of an exhibit at the event. The Earth Day event took place at Union Station in Washington, DC on April 22, 2014. Photo Credit: (NASA/Aubrey Gemignani)

  8. Learning More About Our Earth: An Exploration of NASA's Contributions to Earth Science Through Remote Sensing Technologies

    NASA Technical Reports Server (NTRS)

    Lindsay, Francis

    2017-01-01

    NASA is commonly known for its pioneering work in space exploration and the technological advancements that made access to space possible. NASA is now increasingly known for the agency's research and technologies that support the Earth sciences. This is a presentation focusing on NASA's Earth science efforts told mostly through the technological innovations NASA uses to achieve a greater understanding of the Earth, making it possible to explore the Earth as a system. Enabling this science is NASA's fleet of over two dozen Earth science spacecraft, supported by aircraft, ships and ground observations. NASA's Earth Observing System (EOS) is a coordinated series of polar-orbiting and low inclination satellites for long-term global observations of the land surface, biosphere, solid Earth, atmosphere, and oceans. With the launching of the three flagship satellite missions, Terra, Aqua and Aura, beginning in 1999, NASA's initial Mission to Planet Earth made it possible to measure aspects of the environment that touch the lives of every person around the world. NASA harnessing the unique space-based platform means, fortunately, no planet is better studied than the one we actually live on.

  9. NASA to Survey Earth's Resources

    NASA Technical Reports Server (NTRS)

    Mittauer, R. T.

    1971-01-01

    A wide variety of the natural resources of earth and man's management of them will be studied by an initial group of foreign and domestic scientists tentatively chosen by the National Aeronautics and Space Administration to analyze data to be gathered by two earth-orbiting spacecraft. The spacecraft are the first Earth Resources Technology Satellite (ERTS-A) and the manned Skylab which will carry an Earth Resources Experiment Package (EREP). In the United States, the initial experiments will study the feasibility of remote sensing from a satellite in gathering information on ecological problems. The objective of both ERTS and EREP aboard Skylab is to obtain multispectral images of the surface of the earth with high resolution remote sensors and to process and distribute the images to scientific users in a wide variety of disciplines. The ERTS-A, EREP, and Skylab systems are described and their operation is discussed.

  10. La replantation digitale, résultats et complications: étude d’une série de 18 cas

    PubMed Central

    Idrissi, Mohammed El; Elibrahimi, Abdelhalim; Shimi, Mohammed; Elmrini, Abdelmajid

    2016-01-01

    Les amputations digitales sont des lésions fréquentes, la majorité étant provoquée par des accidents de travail. Les techniques microchirurgicales représentent une alternative pour réparer ces amputations. L'objectif de ce travail est de rapporter notre expérience dans la replantation digitale à travers l'étude de 18 cas. Nous avons mené une étude rétrospective, étalée entre Juin 2013 et Janvier 2015, incluant 14 patients présentant une amputation totale ou subtotale des doigts. Nous avons inclus dans notre série toutes les replantations unidigitales et multidigitales réalisées en aval de l'insertion distale du tendon fléchisseur superficiel ainsi que les replantations digitales réalisées en amont de l'insertion distale du tendon fléchisseur superficiel. Nous avons opéré ces patients selon le procédé classique de réimplantation digitale. Cinq replantations ont été secondairement régularisées. Parmi les 18 replantations, huit replantions digitales ont favorablement évolué puisque la replantation a permis de restituer un secteur complet de mobilité passive et active du doigt opéré sans chirurgie de reprise et sans complication secondaire précoce et tardive. Dans notre étude nous avons noté des résultats satisfaisants, malgré les conditions difficiles notamment le conditionnement initial du doigt amputé, et le délai de prise en charge retardé. Le développement et la maîtrise de la microchirurgie a permis de changer le pronostic de ces amputations à retentissement fonctionnel et psychologique difficile, les résultats de notre série sont encourageants pour a mise en place d'un service SOS main au Maroc. PMID:27795781

  11. L’expérience d’une patiente qui reçoit des soins pour la démence

    PubMed Central

    Frank, Christopher; Forbes, Rev Faye

    2017-01-01

    Résumé Objectif Permettre aux médecins de famille de comprendre « l’expérience vécue » de la démence de la bouche d’une personne atteinte de démence—Faye Forbes, ministre anglicane de 64 ans atteinte de la maladie d’Alzheimer, qui donne son point de vue sur comment vivre avec la démence—et utiliser cette information pour améliorer les soins et les résultats. Sources d’information Une recherche a été effectuée dans MEDLINE sur Ovid entre janvier 2005 et février 2015, à l’aide des mots-clés anglais suivants : dementia, caregiver, perspectives et quality of health care. Les articles qui s’adressaient aux médecins de famille ont été sélectionnés. Des revues pertinentes et des articles de recherche originaux ont été utilisés, le cas échéant, s’ils s’appliquaient aux personnes atteintes de démence et à leurs soignants. Message principal Plusieurs cadres de référence organisent les principales expériences décrites par les patients et leurs soignants. Nous avons utilisé une revue de la littérature qualitative pour fournir un cadre de référence résumant l’expérience de Faye, en fonction des thèmes suivants : tenter d’obtenir un diagnostic, accéder au soutien et aux services, besoins en matière d’information, prise en charge de la maladie, et communication et attitudes. Conclusion Les médecins doivent tenir compte de ces thèmes lorsqu’ils planifient la prise en charge des personnes atteintes de démence. Il importe de tenter de comprendre l’expérience et le point de vue des personnes atteintes de démence et de leurs soignants afin de pouvoir dispenser des soins optimaux. PMID:28115451

  12. Evidence against a chondritic Earth.

    PubMed

    Campbell, Ian H; O'Neill, Hugh St C

    2012-03-28

    The (142)Nd/(144)Nd ratio of the Earth is greater than the solar ratio as inferred from chondritic meteorites, which challenges a fundamental assumption of modern geochemistry--that the composition of the silicate Earth is 'chondritic', meaning that it has refractory element ratios identical to those found in chondrites. The popular explanation for this and other paradoxes of mantle geochemistry, a hidden layer deep in the mantle enriched in incompatible elements, is inconsistent with the heat flux carried by mantle plumes. Either the matter from which the Earth formed was not chondritic, or the Earth has lost matter by collisional erosion in the later stages of planet formation.

  13. Carbon cycling and snowball Earth.

    PubMed

    Goddéris, Yves; Donnadieu, Yannick

    2008-12-18

    The possibility that Earth witnessed episodes of global glaciation during the latest Precambrian challenges our understanding of the physical processes controlling the Earth's climate. Peltier et al. suggest that a 'hard snowball Earth' state may have been prevented owing to the release of CO(2) from the oxidation of dissolved organic carbon (DOC) in the ocean as the temperature decreased. Here we show that the model of Peltier et al. is not self-consistent as it implies large fluctuations of the ocean alkalinity content without providing any processes to account for it. Our findings suggest that the hard snowball Earth hypothesis is still valid.

  14. Sally Ride EarthKAM - Automated Image Geo-Referencing Using Google Earth Web Plug-In

    NASA Technical Reports Server (NTRS)

    Andres, Paul M.; Lazar, Dennis K.; Thames, Robert Q.

    2013-01-01

    Sally Ride EarthKAM is an educational program funded by NASA that aims to provide the public the ability to picture Earth from the perspective of the International Space Station (ISS). A computer-controlled camera is mounted on the ISS in a nadir-pointing window; however, timing limitations in the system cause inaccurate positional metadata. Manually correcting images within an orbit allows the positional metadata to be improved using mathematical regressions. The manual correction process is time-consuming and thus, unfeasible for a large number of images. The standard Google Earth program allows for the importing of KML (keyhole markup language) files that previously were created. These KML file-based overlays could then be manually manipulated as image overlays, saved, and then uploaded to the project server where they are parsed and the metadata in the database is updated. The new interface eliminates the need to save, download, open, re-save, and upload the KML files. Everything is processed on the Web, and all manipulations go directly into the database. Administrators also have the control to discard any single correction that was made and validate a correction. This program streamlines a process that previously required several critical steps and was probably too complex for the average user to complete successfully. The new process is theoretically simple enough for members of the public to make use of and contribute to the success of the Sally Ride EarthKAM project. Using the Google Earth Web plug-in, EarthKAM images, and associated metadata, this software allows users to interactively manipulate an EarthKAM image overlay, and update and improve the associated metadata. The Web interface uses the Google Earth JavaScript API along with PHP-PostgreSQL to present the user the same interface capabilities without leaving the Web. The simpler graphical user interface will allow the public to participate directly and meaningfully with EarthKAM. The use of

  15. Sun-Earth Day, 2001

    NASA Technical Reports Server (NTRS)

    Adams, Mitzi L.; Mortfield, P.; Hathaway, D. H.; Whitaker, Ann F. (Technical Monitor)

    2001-01-01

    To promote awareness of the Sun-Earth connection, NASA's Marshall Space Flight Center, in collaboration with the Stanford SOLAR Center, sponsored a one-day Sun-Earth Day event on April 27, 2001. Although "celebrated" on only one day, teachers and students from across the nation, prepared for over a month in advance. Workshops were held in March to train teachers. Students performed experiments, results of which were shared through video clips and an internet web cast. Our poster includes highlights from student experiments (grades 2 - 12), lessons learned from the teacher workshops and the event itself, and plans for Sun-Earth Day 2002.

  16. Rare earth gas laser

    DOEpatents

    Krupke, W.F.

    1975-10-31

    A high energy gas laser with light output in the infrared or visible region of the spectrum is described. Laser action is obtained by generating vapors of rare earth halides, particularly neodymium iodide or, to a lesser extent, neodymium bromide, and disposing the rare earth vapor medium in a resonant cavity at elevated temperatures; e.g., approximately 1200/sup 0/ to 1400/sup 0/K. A particularly preferred gaseous medium is one involving a complex of aluminum chloride and neodymium chloride, which exhibits tremendously enhanced vapor pressure compared to the rare earth halides per se, and provides comparable increases in stored energy densities.

  17. Earthing the Human Body Influences Physiologic Processes

    PubMed Central

    Sokal, Karol

    2011-01-01

    Abstract Objectives This study was designed to answer the question: Does the contact of the human organism with the Earth via a copper conductor affect physiologic processes? Subjects and experiments Five (5) experiments are presented: experiment 1—effect of earthing on calcium–phosphate homeostasis and serum concentrations of iron (N = 84 participants); experiment 2—effect of earthing on serum concentrations of electrolytes (N = 28); experiment 3—effect of earthing on thyroid function (N = 12); experiment 4—effect of earthing on glucose concentration (N = 12); experiment 5—effect of earthing on immune response to vaccine (N = 32). Subjects were divided into two groups. One (1) group of people was earthed, while the second group remained without contact with the Earth. Blood and urine samples were examined. Results Earthing of an electrically insulated human organism during night rest causes lowering of serum concentrations of iron, ionized calcium, inorganic phosphorus, and reduction of renal excretion of calcium and phosphorus. Earthing during night rest decreases free tri-iodothyronine and increases free thyroxine and thyroid-stimulating hormone. The continuous earthing of the human body decreases blood glucose in patients with diabetes. Earthing decreases sodium, potassium, magnesium, iron, total protein, and albumin concentrations while the levels of transferrin, ferritin, and globulins α1, α2, β, and γ increase. These results are statistically significant. Conclusions Earthing the human body influences human physiologic processes. This influence is observed during night relaxation and during physical activity. Effect of the earthing on calcium–phosphate homeostasis is the opposite of that which occurs in states of weightlessness. It also increases the activity of catabolic processes. It may be the primary factor regulating endocrine and nervous systems. PMID:21469913

  18. A strategy for Earth science from space in the 1980s. Part 1: Solid earth and oceans

    NASA Technical Reports Server (NTRS)

    1982-01-01

    The report develops a ten-year science strategy for investigating the solid earth and dynamics of world oceans from Earth orbit. The strategy begins from the premise that earth studies have proceeded to the point where further advances in understanding Earth processes must be based on a global perspective and that the U.S. is technically ready to begin a global study approach from Earth orbit. The major areas of study and their fundamental problems are identified. The strategy defines the primary science objectives to be addressed and the essential measurements and precision to achieve them.

  19. The Earth's Biosphere

    NASA Technical Reports Server (NTRS)

    2002-01-01

    In the last five years, scientists have been able to monitor our changing planet in ways never before possible. The Sea-viewing Wide Field-of-View Sensor (SeaWiFS), aboard the OrbView-2 satellite, has given researchers an unprecedented view of the biological engine that drives life on Earth-the countless forms of plants that cover the land and fill the oceans. 'There is no question the Earth is changing. SeaWiFS has enabled us, for the first time, to monitor the biological consequences of that change-to see how the things we do, as well as natural variability, affect the Earth's ability to support life,' said Gene Carl Feldman, SeaWiFS project manager at NASA's Goddard Space Flight Center, Greenbelt, Md. SeaWiFS data, based on continuous daily global observations, have helped scientists make a more accurate assessment of the oceans' role in the global carbon cycle. The data provide a key parameter in a number of ecological and environmental studies as well as global climate-change modeling. The images of the Earth's changing land, ocean and atmosphere from SeaWiFS have documented many previously unrecognized phenomena. The image above shows the global biosphere from June 2002 measured by SeaWiFS. Data in the oceans is chlorophyll concentration, a measure of the amount of phytoplankton (microscopic plants) living in the ocean. On land SeaWiFS measures Normalized Difference Vegetation Index, an indication of the density of plant growth. For more information and images, read: SeaWiFS Sensor Marks Five Years Documenting Earth'S Dynamic Biosphere Image courtesy SeaWiFS project and copyright Orbimage.

  20. Atmospheric Expression of Seasonality on the Early Earth and Earth-like Exoplanets

    NASA Astrophysics Data System (ADS)

    Olson, S. L.; Schwieterman, E. W.; Reinhard, C. T.; Ridgwell, A.; Lyons, T. W.

    2017-12-01

    Biologically modulated seasonality impacts nearly every chemical constituent of Earth's atmosphere. For example, seasonal shifts in the balance of photosynthesis and respiration manifest as striking oscillation in the atmospheric abundance of CO2 and O2. Similar temporal variability is likely on other inhabited worlds, and seasonality is often regarded as a potential exoplanetary biosignature. Seasonality is a particularly intriguing biosignature because it may allow us to identify life through the abundance of spectrally active gases that are not uniquely biological in origin (e.g., CO2 or CH4). To date, however, the discussion of seasonality as a biosignature has been exclusively qualitative. We lack both quantitative constraints on the likelihood of spectrally detectable seasonality elsewhere and a framework for evaluating potential false positive scenarios (e.g., seasonal CO2 ice sublimation). That is, we do not yet know for which gases, and under which conditions, we could expect to detect seasonality and reliably infer the presence of an active biosphere. The composition of Earth's atmosphere has changed dramatically through time, and consequently, the atmospheric expression of seasonality has necessarily changed throughout Earth history as well. Thus, Earth offers several case studies for examining the potential for observable seasonality on chemically and tectonically diverse exoplanets. We outline an approach for exploring the history of seasonality on Earth via coupled biogeochemical and photochemical models, with particular emphasis on the seasonal cycles of CO2, CH4, and O2/O3. We also discuss the remote detectability of these seasonal signals on directly imaged exoplanets via reflectance and emission spectra. We suggest that seasonality in O2 on the early Earth was biogeochemically significant—and that seasonal cycles in O3, an indirect biological product coupled to biogenic O2, may be a readily detectable fingerprint of life in the absence of

  1. Ancient and Medieval Earth in Armenia

    NASA Astrophysics Data System (ADS)

    Farmanyan, S. V.

    2015-07-01

    Humankind has always sought to recognize the nature of various sky related phenomena and tried to give them explanations. The purpose of this study is to identify ancient Armenians' pantheistic and cosmological perceptions, world view, notions and beliefs related to the Earth. The paper focuses on the structure of the Earth and many other phenomena of nature that have always been on a major influence on ancient Armenians thinking. In this paper we have compared the term Earth in 31 languages. By discussing and comparing Universe structure in various regional traditions, myths, folk songs and phraseological units we very often came across to "Seven Heavens" (Seven heavens is a part of religious cosmology found in many major religions such as Islam, Judaism, Hinduism and Christianity (namely Catholicism) and "Seven Earths". Armenians in their turn divided Earth and Heavens into seven layers. And in science too, both the Earth and the Heavens have 7 layers. The Seven Heavens refer to the layers of our atmosphere. The Seven Earths refer to the layers of the Earth (from core to crust), as well as seven continents. We conclude that the perception of celestial objects varies from culture to culture and preastronomy had a significant impact on humankind, particularly on cultural diversities.

  2. BENNU’S JOURNEY - Early Earth

    NASA Image and Video Library

    2017-12-08

    This is an artist's concept of the young Earth being bombarded by asteroids. Scientists think these impacts could have delivered significant amounts of organic matter and water to Earth. Image Credit: NASA's Goddard Space Flight Center Conceptual Image Lab The Origins Spectral Interpretation Resource Identification Security -- Regolith Explorer spacecraft (OSIRIS-REx) will travel to a near-Earth asteroid, called Bennu, and bring a sample back to Earth for study. The mission will help scientists investigate how planets formed and how life began, as well as improve our understanding of asteroids that could impact Earth. OSIRIS-REx is scheduled for launch in late 2016. As planned, the spacecraft will reach its asteroid target in 2018 and return a sample to Earth in 2023. Watch the full video: youtu.be/gtUgarROs08 Learn more about NASA’s OSIRIS-REx mission and the making of Bennu’s Journey: www.nasa.gov/content/goddard/bennus-journey/ More information on the OSIRIS-REx mission is available at: www.nasa.gov/mission_pages/osiris-rex/index.html www.asteroidmission.org NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

  3. Supporting Inquiry-based Earth System Science Instruction with Middle and High School Earth Science Teachers

    NASA Astrophysics Data System (ADS)

    Finkel, L.; Varner, R.; Froburg, E.; Smith, M.; Graham, K.; Hale, S.; Laura, G.; Brown, D.; Bryce, J.; Darwish, A.; Furman, T.; Johnson, J.; Porter, W.; von Damm, K.

    2007-12-01

    The Transforming Earth System Science Education (TESSE) project, a partnership between faculty at the University of New Hampshire, Pennsylvania State University, Elizabeth City State University and Dillard University, is designed to enrich the professional development of in-service and pre-service Earth science teachers. One goal of this effort is to help teachers use an inquiry-based approach to teaching Earth system science in their classrooms. As a part of the TESSE project, 42 pre-service and in-service teachers participated in an intensive two-week summer institute at UNH taught by Earth scientists and science educators from TESSE partnership institutions. The institute included instruction about a range of Earth science system topics as well as an introduction to teaching Earth science using an inquiry-based approach. In addition to providing teachers with information about inquiry-based science teaching in the form of sample lesson plans and opportunities to revise traditional lessons and laboratory exercises to make them more inquiry-based, TESSE instructors modeled an inquiry- based approach in their own teaching as much as possible. By the end of the Institute participants had developed lesson plans, units, or year-long course overviews in which they were expected to explain the ways in which they would include an inquiry-based approach in their Earth science teaching over the course of the school year. As a part of the project, graduate fellows (graduate students in the earth sciences) will work with classroom teachers during the academic year to support their implementation of these plans as well as to assist them in developing a more comprehensive inquiry-based approach in the classroom.

  4. Les infestations par les poux de tête : une mise à jour clinique.

    PubMed

    Cummings, Carl; Finlay, Jane C; MacDonald, Noni E

    2018-02-01

    Les infestations par les poux de tête ( Pediculus humanus capitis ) ne constituent ni un risque sanitaire primaire ni un vecteur de maladie, mais représentent plutôt un problème de société au coût impor- tant. Pour diagnostiquer une infestation, il faut déceler un pou vivant. Même si les pyréthines et la perméthrine demeurent les traitements de première intention au Canada, la solution de myristate d'isopropyle et de ST-cyclométhicone et la diméticone peuvent être envisagées en deuxième intention après un échec thérapeutique démontré.

  5. Earth as art 4

    USGS Publications Warehouse

    ,

    2016-03-29

    Landsat 8 is the latest addition to the long-running series of Earth-observing satellites in the Landsat program that began in 1972. The images featured in this fourth installment of the Earth As Art collection were all acquired by Landsat 8. They show our planet’s diverse landscapes with remarkable clarity.Landsat satellites see the Earth as no human can. Not only do they acquire images from the vantage point of space, but their sensors record infrared as well as visible wavelengths of light. The resulting images often reveal “hidden” details of the Earth’s land surface, making them invaluable for scientific research.As with previous Earth As Art exhibits, these Landsat images were selected solely for their aesthetic appeal. Many of the images have been manipulated to enhance color variations or details. They are not intended for scientific interpretation—only for your viewing pleasure. What do you see in these unique glimpses of the Earth’s continents, islands, and coastlines?

  6. Venus - Lessons for earth

    NASA Technical Reports Server (NTRS)

    Hunten, D. M.

    1992-01-01

    The old idea that Venus might possess surface conditions to those of an overcast earth has been thoroughly refuted by space-age measurements. Instead, the two planets may have started out similar, but diverged because of the greater solar flux at Venus. This cannot be proved, but is consistent with everything known. A runaway greenhouse effect could have evaporated an 'ocean'. The hydrogen would escape, and most of the oxygen would be incorporated into the crust. Without liquid water, CO2 would remain in the atmosphere. Chlorine atoms would catalyze the recombination of any free oxygen back to CO2. The same theories apply to the future of the earth, and to the explanation of the polar ozone holes; the analogies are striking. There is no likelihood that the earth will actually come to resemble Venus, but Venus serves both as a warning that major environmental effects can flow from seemingly small causes, and as a testbed for the predictive models of the earth.

  7. Earth Observation

    NASA Image and Video Library

    2010-08-23

    ISS024-E-016042 (23 Aug. 2010) --- This night time view captured by one of the Expedition 24 crew members aboard the International Space Station some 220 miles above Earth is looking southward from central Romania over the Aegean Sea toward Greece and it includes Thessaloniki (near center), the larger bright mass of Athens (left center), and the Macedonian capital of Skopje (lower right). Center point coordinates of the area pictured are 46.4 degrees north latitude and 25.5 degrees east longitude. The picture was taken in August and was physically brought back to Earth on a disk with the return of the Expedition 25 crew in November 2010.

  8. Earth Science

    NASA Image and Video Library

    2004-09-15

    Except for a small portion of the International Space Station (ISS) in the foreground, Hurricane Ivan, one of the strongest hurricanes on record, fills this image over the northern Gulf of Mexico. As the downgraded category 4 storm approached landfall on the Alabama coast Wednesday afternoon on September 15, 2004, sustained winds in the eye of the wall were reported at about 135 mph. The hurricane was photographed by astronaut Edward M. (Mike) Fincke from aboard the ISS at an altitude of approximately 230 miles. Crew Earth Observations record Earth surface changes over time, as well as more fleeting events such as storms, floods, fires, and volcanic eruptions.

  9. Earth Science

    NASA Image and Video Library

    2004-09-15

    This image hosts a look into the eye of Hurricane Ivan, one of the strongest hurricanes on record, as the storm approached landfall on the central Gulf coast Wednesday afternoon on September 15, 2004. The hurricane was photographed by astronaut Edward M. (Mike) Fincke from aboard the International Space Station (ISS) at an altitude of approximately 230 miles. At the time, sustained winds in the eye of the wall were reported at about 135 mph as the downgraded category 4 storm approached the Alabama coast. Crew Earth Observations record Earth surface changes over time, as well as more fleeting events such as storms, floods, fires, and volcanic eruptions.

  10. Rare earth elements: end use and recyclability

    USGS Publications Warehouse

    Goonan, Thomas G.

    2011-01-01

    Rare earth elements are used in mature markets (such as catalysts, glassmaking, lighting, and metallurgy), which account for 59 percent of the total worldwide consumption of rare earth elements, and in newer, high-growth markets (such as battery alloys, ceramics, and permanent magnets), which account for 41 percent of the total worldwide consumption of rare earth elements. In mature market segments, lanthanum and cerium constitute about 80 percent of rare earth elements used, and in new market segments, dysprosium, neodymium, and praseodymium account for about 85 percent of rare earth elements used. Regardless of the end use, rare earth elements are not recycled in large quantities, but could be if recycling became mandated or very high prices of rare earth elements made recycling feasible.

  11. Alkali element constraints on Earth-Moon relations

    NASA Technical Reports Server (NTRS)

    Norman, M. D.; Drake, M. J.; Jones, J. H.

    1994-01-01

    Given their range of volatilities, alkali elements are potential tracers of temperature-dependent processes during planetary accretion and formation of the Earth-Moon system. Under the giant impact hypothesis, no direct connection between the composition of the Moon and the Earth is required, and proto-lunar material does not necessarily experience high temperatures. Models calling for multiple collisions with smaller planetesimals derive proto-lunar materials mainly from the Earth's mantle and explicitly invoke vaporization, shock melting and volatility-related fractionation. Na/K, K/Rb, and Rb/Cs should all increase in response to thermal volatization, so theories which derive the Moon substantially from Earth's mantle predict these ratios will be higher in the Moon than in the primitive mantle of the Earth. Despite the overall depletion of volatile elements in the Moon, its Na/K and K/Rb are equal to or less than those of Earth. A new model presented here for the composition of Earth's continental crust, a major repository of the alkali elements, suggests the Rb/Cs of the Moon is also less than that of Earth. Fractionation of the alkali elements between Earth and Moon are in the opposite sense to predictions based on the relative volatilities of these elements, if the Moon formed by high-T processing of Earth's mantle. Earth, rather than the Moon, appears to carry a signature of volatility-related fractionation in the alkali elements. This may reflect an early episode of intense heating on Earth with the Moon's alkali budget accreting from cooler material.

  12. Mineral resource of the month: rare earth elements

    USGS Publications Warehouse

    ,

    2011-01-01

    The article provides information on rare earth elements, which are group of 17 natural metallic elements. The rare earth elements are scandium, yttrium and lanthanides and classified into light rare earth elements (LREE) and heavy rate earth elements (HREE). The principal ores of the rare earth elements are identified. An overview of China's production of 97 percent of the rare earths in the world is provided. Commercial applications of rare earths are described.

  13. NASA's Earth Science Data Systems

    NASA Technical Reports Server (NTRS)

    Ramapriyan, H. K.

    2015-01-01

    NASA's Earth Science Data Systems (ESDS) Program has evolved over the last two decades, and currently has several core and community components. Core components provide the basic operational capabilities to process, archive, manage and distribute data from NASA missions. Community components provide a path for peer-reviewed research in Earth Science Informatics to feed into the evolution of the core components. The Earth Observing System Data and Information System (EOSDIS) is a core component consisting of twelve Distributed Active Archive Centers (DAACs) and eight Science Investigator-led Processing Systems spread across the U.S. The presentation covers how the ESDS Program continues to evolve and benefits from as well as contributes to advances in Earth Science Informatics.

  14. Accessible Near-Earth Objects (NEOs)

    NASA Technical Reports Server (NTRS)

    Barbee, Brent W.

    2015-01-01

    Near Earth Objects (NEOs) are asteroids and comets whose orbits are in close proximity to Earth's orbit; specifically, they have perihelia less than 1.3 astronomical units. NEOs particularly near Earth asteroids (NEAs) are identified as potential destinations for future human exploration missions. In this presentation I provide an overview of the current state of knowledge regarding the astrodynamical accessibility of NEAs according to NASA's Near Earth Object Human Space Flight Accessible Targets Study (NHATS). I also investigate the extremes of NEA accessibility using case studies and illuminate the fact that a space-based survey for NEOs is essential to expanding the set of known accessible NEAs for future human exploration missions.

  15. Spaceship Earth Curriculum Project.

    ERIC Educational Resources Information Center

    McInnis, Noel; And Others

    Three separate papers from the Project are included in this document. One of these, by the Center staff, is entitled "Potentials of the Spaceship Earth Metaphor". It discusses static, dynamic, and analogic representations of spaceship earth and their educational value. A second paper, "Some Resources for Introducing Environmental…

  16. Crescent Earth and Moon

    NASA Image and Video Library

    1996-08-29

    This picture of a crescent-shaped Earth and Moon, the first of its kind ever taken by a spacecraft, was recorded Sept. 18, 1977, by NASA Voyager 1 when it was 7.25 million miles 11.66 million kilometers from Earth. http://photojournal.jpl.nasa.gov/catalog/PIA00013

  17. Une étude rétrospective sur l'incidence de l'insuffisance rénale chronique dans le service de Médecine Interne et Néphrologie du Centre Hospitalier Universitaire d'Antananarivo

    PubMed Central

    Ramilitiana, Benja; Ranivoharisoa, Eliane Mikkelsen; Dodo, Mihary; Razafimandimby, Evanirina; Randriamarotia, Willy Franck

    2016-01-01

    L'insuffisance rénale chronique est un problème de santé publique au niveau mondial. Dans les pays développés, cette affection survient essentiellement chez les sujets âgés, mais en Afrique, elle s'installe plutôt chez les sujets jeunes actifs. C'est une affection de lourde prise en charge dans un pays à faible revenu à cause de ses coûts. Notre but est de décrire les aspects épidémiologiques des nouveaux cas d'insuffisance rénale chronique à Madagascar. Il s'agit d'une étude rétrospective descriptive de 3 ans partant du 1er janvier 2007 au 31 décembre 2009 dans le service de Médecine Interne et Néphrologie du Centre Hospitalier Universitaire d'Antananarivo portant sur 239 patients diagnostiqués comme une insuffisance rénale chronique. L'incidence était de 8,51% parmi les patients hospitalisés dans le service. L’âge moyen des patients était de 45,4 ans avec des extrêmes de 16 et 82 ans et un sex-ratio de 1,46. Le principal antécédent était l'hypertension artérielle (59,8%). L'insuffisance rénale chronique était terminale dans 75,31% des cas (n=180). Les causes de l'insuffisance rénale chronique étaient dominées par la glomérulonéphrite chronique (40,1%), la néphroangiosclérose (35,5%). L'hémodialyse était réalisée chez 3 patients (1,26%), aucun patient n’était pas programmé pour une greffe rénale. Le taux de mortalité dans le service était de 28,87%. L'insuffisance rénale chronique est une maladie de pronostic redoutable et handicapante qui affecte les sujets jeunes à Madagascar. Son traitement reste inaccessible dans la majorité des patients. L'accent doit donc être mis principalement sur la prévention notamment une bonne prise en charge précoce des infections, de l'hypertension artérielle et du diabète pour réduire ses impacts négatifs sur la santé communautaire et publique. Le projet de la transplantation rénale - donneur vivant, traitement efficace et moins coûteux par rapport à l

  18. Detecting Water on Super-Earths Using JAVST

    NASA Technical Reports Server (NTRS)

    Deming, D.

    2010-01-01

    Nearby lower train sequence stars host a class of planets known as Super-Earths, that have no analog in our own solar system. Super-Earths are rocky and/or icy planets with masses up to about 10 Earth masses, They are expected to host atmospheres generated by a number of processes including accretion of chondritic material. Water vapor should be a common constituent of super-Earth atmospheres, and may be detectable in transiting super-Earths using transmission spectroscopy during primar y eclipse, and emission spectroscopy at secondary eclipse. I will discuss the prospects for super-Earth atmospheric measurements using JWST.

  19. How Big is Earth?

    NASA Astrophysics Data System (ADS)

    Thurber, Bonnie B.

    2015-08-01

    How Big is Earth celebrates the Year of Light. Using only the sunlight striking the Earth and a wooden dowel, students meet each other and then measure the circumference of the earth. Eratosthenes did it over 2,000 years ago. In Cosmos, Carl Sagan shared the process by which Eratosthenes measured the angle of the shadow cast at local noon when sunlight strikes a stick positioned perpendicular to the ground. By comparing his measurement to another made a distance away, Eratosthenes was able to calculate the circumference of the earth. How Big is Earth provides an online learning environment where students do science the same way Eratosthenes did. A notable project in which this was done was The Eratosthenes Project, conducted in 2005 as part of the World Year of Physics; in fact, we will be drawing on the teacher's guide developed by that project.How Big Is Earth? expands on the Eratosthenes project by providing an online learning environment provided by the iCollaboratory, www.icollaboratory.org, where teachers and students from Sweden, China, Nepal, Russia, Morocco, and the United States collaborate, share data, and reflect on their learning of science and astronomy. They are sharing their information and discussing their ideas/brainstorming the solutions in a discussion forum. There is an ongoing database of student measurements and another database to collect data on both teacher and student learning from surveys, discussions, and self-reflection done online.We will share our research about the kinds of learning that takes place only in global collaborations.The entrance address for the iCollaboratory is http://www.icollaboratory.org.

  20. Story-telling, Earth-Sciences and Geoethics

    NASA Astrophysics Data System (ADS)

    Bohle, Martin; Sibilla, Anna; Graells, Robert Casals i.

    2015-04-01

    People are engineers, even the artist. People like stories, even the engineers. Engineering shapes the intersections of humans and their environments including with the geosphere. Geoethics considers values upon which to base practices how to intersect the geosphere. Story-telling is a skilful human practice to describe perception of values in different contexts to influence their application. Traditional earth-centric narrations of rural communities have been lost in the global urbanisation process. These former-time narrations related to the "sacrum" - matters not possible to be explained with reasoning. Science and technology, industrialisation and global urbanisation require an other kind of earth-centric story-telling. Now at the fringe of the Anthropocene, humans can base their earth-centricity on knowledge and scientific thinking. We argue that modern story-telling about the functioning of Earth's systems and the impact of humankind's activities on these systems is needed, also in particular because citizens rarely can notice how the geosphere intersects with their daily dealings; putting weather and disasters aside. Modern earth-centric story-telling would offer citizens opportunities to develop informed position towards humankind's place within earth-systems. We argue that such "earth-science story-lines" should be part of the public discourse to engage citizens who have more or less "expert-knowledge". Understanding the functioning of the Earth is needed for economy and values suitable for an anthropophil society. Multi-faceted discussion of anthropogenic global change and geoengineering took off recently; emerging from discussions about weather and hazard mitigation. Going beyond that example; we illustrate opportunities for rich story-telling on intersections of humans' activities and the geosphere. These 'modern narrations' can weave science, demographics, linguistics and cultural histories into earth-centric stories around daily dealings of citizens

  1. EarthLabs: A National Model for Earth Science Lab Courses

    NASA Astrophysics Data System (ADS)

    McDaris, J. R.; Dahlman, L.; Barstow, D.

    2008-12-01

    As a response to the need for more rigorous, inquiry-based high school Earth science courses, a coalition of scientists, educators, and five states have created EarthLabs, a set of pilot modules that can serve as a national model for lab-based science courses. The content of EarthLabs chapters focuses on Earth system science and environmental literacy and conforms to the National Science Education Standards as well as the states' curriculum frameworks. The effort is funded by NOAA's Environmental Literacy program. The pilot modules present activities on Corals, Drought, Fisheries, and Hurricanes. The Fisheries and Hurricanes units were reviewed and field-tested by educators in Texas and Arizona. The feedback from this evaluation led to revisions of these units and guided development of the Corals and Drought chapters. Each module consists of activities that use online data sets, satellite imagery, web-based readings, and hands-on laboratory experiments. The project comprises two separate websites, one for the instructor and one for students. The instructor's site contains the pedagogical underpinnings for each lab including teaching materials, assessment strategies, and the alignment of activities with state and national science standards. The student site provides access to all materials that students need to complete the activities or, in the case of the hands-on labs, where they access additional information to help extend their learning. There are also formative and summative questions embedded in the student webpages to help scaffold learning through the activities.

  2. Earth Eclipses the Sun

    NASA Image and Video Library

    2017-02-21

    Several times a day for a few days the Earth completely blocked the Sun for about an hour due to NASA's Solar Dynamics Observatory's orbital path (Feb. 15, 2017). The edge of the Earth is not crisp, but kind of fuzzy due to Earth's atmosphere. This frame from a video shows the ending of one such eclipse over -- just seven minutes. The sun is shown in a wavelength of extreme ultraviolet light. These eclipses re-occur about every six months. The Moon blocks SDO's view of the sun on occasion as well. Movies are available at http://photojournal.jpl.nasa.gov/catalog/PIA21461

  3. On the Sun, Earth, and Clocks.

    ERIC Educational Resources Information Center

    Easton, D.

    1985-01-01

    Discusses motions of the sun and earth in relation to the accuracy of clocks. Effect of eccentricity of the earth's orbit, efect of inclination of the earth's axis, and combination of these two effects are considered. The accuracy of sundials is also discussed. (DH)

  4. Interacting with Petabytes of Earth Science Data using Jupyter Notebooks, IPython Widgets and Google Earth Engine

    NASA Astrophysics Data System (ADS)

    Erickson, T. A.; Granger, B.; Grout, J.; Corlay, S.

    2017-12-01

    The volume of Earth science data gathered from satellites, aircraft, drones, and field instruments continues to increase. For many scientific questions in the Earth sciences, managing this large volume of data is a barrier to progress, as it is difficult to explore and analyze large volumes of data using the traditional paradigm of downloading datasets to a local computer for analysis. Furthermore, methods for communicating Earth science algorithms that operate on large datasets in an easily understandable and reproducible way are needed. Here we describe a system for developing, interacting, and sharing well-documented Earth Science algorithms that combines existing software components: Jupyter Notebook: An open-source, web-based environment that supports documents that combine code and computational results with text narrative, mathematics, images, and other media. These notebooks provide an environment for interactive exploration of data and development of well documented algorithms. Jupyter Widgets / ipyleaflet: An architecture for creating interactive user interface controls (such as sliders, text boxes, etc.) in Jupyter Notebooks that communicate with Python code. This architecture includes a default set of UI controls (sliders, dropboxes, etc.) as well as APIs for building custom UI controls. The ipyleaflet project is one example that offers a custom interactive map control that allows a user to display and manipulate geographic data within the Jupyter Notebook. Google Earth Engine: A cloud-based geospatial analysis platform that provides access to petabytes of Earth science data via a Python API. The combination of Jupyter Notebooks, Jupyter Widgets, ipyleaflet, and Google Earth Engine makes it possible to explore and analyze massive Earth science datasets via a web browser, in an environment suitable for interactive exploration, teaching, and sharing. Using these environments can make Earth science analyses easier to understand and reproducible, which may

  5. Laurel Clark Earth Camp: Building a Framework for Teacher and Student Understanding of Earth Systems

    NASA Astrophysics Data System (ADS)

    Colodner, D.; Buxner, S.; Schwartz, K.; Orchard, A.; Titcomb, A.; King, B.; Baldridge, A.; Thomas-Hilburn, H.; Crown, D. A.

    2013-04-01

    Laurel Clark Earth Camp is designed to inspire teachers and students to study their world through field experiences, remote sensing investigations, and hands on exploration, all of which lend context to scientific inquiry. In three different programs (for middle school students, for high school students, and for teachers) participants are challenged to understand Earth processes from the perspectives of both on-the ground inspection and from examination of satellite images, and use those multiple perspectives to determine best practices on both a societal and individual scale. Earth Camp is a field-based program that takes place both in the “natural” and built environment. Middle School Earth Camp introduces students to a variety of environmental science, engineering, technology, and societal approaches to sustainability. High School Earth Camp explores ecology and water resources from southern Arizona to eastern Utah, including a 5 day rafting trip. In both camps, students compare environmental change observed through repeat photography on the ground to changes observed from space. Students are encouraged to utilize their camp experience in considering their future course of study, career objectives, and lifestyle choices. During Earth Camp for Educators, teachers participate in a series of weekend workshops to explore relevant environmental science practices, including water quality testing, biodiversity surveys, water and light audits, and remote sensing. Teachers engage students, both in school and after school, in scientific investigations with this broad based set of tools. Earth Stories from Space is a website that will assist in developing skills and comfort in analyzing change over time and space using remotely sensed images. Through this three-year NASA funded program, participants will appreciate the importance of scale and perspective in understanding Earth systems and become inspired to make choices that protect the environment.

  6. Hands On Earth Science.

    ERIC Educational Resources Information Center

    Weisgarber, Sherry L.; Van Doren, Lisa; Hackathorn, Merrianne; Hannibal, Joseph T.; Hansgen, Richard

    This publication is a collection of 13 hands-on activities that focus on earth science-related activities and involve students in learning about growing crystals, tectonics, fossils, rock and minerals, modeling Ohio geology, geologic time, determining true north, and constructing scale-models of the Earth-moon system. Each activity contains…

  7. Thermal evolution of the earth

    NASA Technical Reports Server (NTRS)

    Spohn, T.

    1984-01-01

    The earth's heat budget and models of the earth's thermal evolution are discussed. Sources of the planetary heat are considered and modes of heat transport are addressed, including conduction, convection, and chemical convection. Thermal and convectional models of the earth are covered, and models of thermal evolution are discussed in detail, including changes in the core, the influence of layered mantle convection on the thermal evolution, and the effect of chemical differentiation on the continents.

  8. Educational and public outreach programs using four-dimensional presentation of the earth and planetary science data with Dagik Earth

    NASA Astrophysics Data System (ADS)

    Saito, A.; Tsugawa, T.; Nagayama, S.; Iwasaki, S.; Odagi, Y.; Kumano, Y.; Yoshikawa, M.; Akiya, Y.; Takahashi, M.

    2011-12-01

    We are developing educational and public outreach programs of the earth and planetary science data using a four-dimensional digital globe system, Dagik Earth. Dagik Earth is a simple and affordable four dimensional (three dimension in space and one dimension in time) presentation system of the earth and planetary scientific results. It can display the Earth and planets in three-dimensional way without glasses, and the time variation of the scientific data can be displayed on the Earth and planets image. It is easier to handle and lower cost than similar systems such as Geocosmos by Miraikan museum, Japan and Science On a Sphere by NOAA. At first it was developed as a presentation tool for public outreach programs in universities and research institutes by earth scientists. And now it is used in classrooms of schools and science museums collaboration with school teachers and museum curators. The three dimensional display can show the Earth and planets in exact form without any distortion, which cannot be achieved with two-dimensional display. Furthermore it can provide a sense of reality. Several educational programs have been developed and carried out in high schools, junior high schools, elementary schools and science centers. Several research institutes have used Dagik Earth in their public outreach programs to demonstrate their novel scientific results to public in universities, research institutes and science cafe events. A community of users and developers of Dagik Earth is being formed in Japan. In the presentation, the outline of Dagik Earth and the educational programs using Dagik Earth will be presented.

  9. Better Than Earth

    NASA Astrophysics Data System (ADS)

    Heller, René

    2015-01-01

    Do we inhabit the best of all possible worlds? German mathematician Gottfried Leibniz thought so, writing in 1710 that our planet, warts and all, must be the most optimal one imaginable. Leibniz's idea was roundly scorned as unscientific wishful thinking, most notably by French author Voltaire in his magnum opus, Candide. Yet Leibniz might find sympathy from at least one group of scientists - the astronomers who have for decades treated Earth as a golden standard as they search for worlds beyond our own solar system. Because earthlings still know of just one living world - our own - it makes some sense to use Earth as a template in the search for life elsewhere, such as in the most Earth-like regions of Mars or Jupiter's watery moon Europa. Now, however, discoveries of potentially habitable planets orbiting stars other than our sun - exoplanets, that is - are challenging that geocentric approach.

  10. Étude par détection de photons des processus électroniques au sein d'une jonction tunnel dans un milieu moléculaire

    NASA Astrophysics Data System (ADS)

    Perronet, K.

    2005-03-01

    Analysis of the luminescence induced by a STM (scanning tunneling microscope) permits to get insights into the electronic processes taking place in a single nanoscopic tunnel junction. We studied a Au(111)/Au junction under vacuum (UHV) and immersed in a molecular medium. The study under UHV reveals the influence of spatial variations of surface local density of states (LDOS) on the luminescence. The emission at the solid-liquid interface is characterized and the role played by the dielectric function is shown. Time correlations between the emitted single photons are then studied. Depending on the liquid immersing the junction, a photon bunching can occur. We link this bunching with structural changes of the junction induced by the presence of a diffusing molecule. If the HOMO LUMO gap of the molecule is small enough, resonant tunnelling paths exist and tunnelling-electron bunching occurs. Finally, the influence of a self-assembled monolayer on the substrate is investigated. Boundings between triphenylene derivatives and Au(111) are too weak, but with chemisorbed alcanethiols, molecular resolution is reached both on the STM image and on the photon map. We show that the contrast on photon map comes from the modulation of the LDOS spatial extension into the barrier due to the S Au bond. The elaboration of organic multilayers is considered as a route for observing the electroluminescence of a single molecule, isolated from the substrate by thiols and to study correlations of electronic origin. We have already optically characterised such a layer using C{60}. La luminescence induite par STM (microscopie à effet tunnel) est une source d'informations d'une grande richesse sur les processus électroniques au sein d'un objet nanoscopique individuel. Nous nous sommes intéressés à une jonction Au/Au(111) sous vide puis dans un milieu moléculaire. L'étude sous vide a permis de montrer l'influence des variations spatiales des densités d'états de la surface. L

  11. Dangerous Near-Earth Asteroids and Meteorites

    NASA Astrophysics Data System (ADS)

    Mickaelian, A. M.; Grigoryan, A. E.

    2015-07-01

    The problem of Near-Earth Objects (NEOs; Astreoids and Meteorites) is discussed. To have an understanding on the probablity of encounters with such objects, one may use two different approaches: 1) historical, based on the statistics of existing large meteorite craters on the Earth, estimation of the source meteorites size and the age of these craters to derive the frequency of encounters with a given size of meteorites and 2) astronomical, based on the study and cataloging of all medium-size and large bodies in the Earth's neighbourhood and their orbits to estimate the probability, angles and other parameters of encounters. Therefore, we discuss both aspects and give our present knowledge on both phenomena. Though dangerous NEOs are one of the main source for cosmic catastrophes, we also focus on other possible dangers, such as even slight changes of Solar irradiance or Earth's orbit, change of Moon's impact on Earth, Solar flares or other manifestations of Solar activity, transit of comets (with impact on Earth's atmosphere), global climate change, dilution of Earth's atmosphere, damage of ozone layer, explosion of nearby Supernovae, and even an attack by extraterrestrial intelligence.

  12. Recovering heavy rare earth metals from magnet scrap

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

    Ott, Ryan T.; McCallum, Ralph W.; Jones, Lawrence L.

    A method of treating rare earth metal-bearing permanent magnet scrap, waste or other material in a manner to recover the heavy rare earth metal content separately from the light rare earth metal content. The heavy rare earth metal content can be recovered either as a heavy rare earth metal-enriched iron based alloy or as a heavy rare earth metal based alloy.

  13. Google Earth: A Virtual Globe for Elementary Geography

    ERIC Educational Resources Information Center

    Britt, Judy; LaFontaine, Gus

    2009-01-01

    Originally called Earth Viewer in 2004, Google Earth was the first virtual globe easily available to the ordinary user of the Internet. Google Earth, at earth.google.com, is a free, 3-dimensional computer model of Earth, but that means more than just a large collection of pretty pictures. It allows the viewer to "fly" anywhere on Earth "to view…

  14. Properties of an Earth-like planet orbiting a Sun-like star: Earth observed by the EPOXI mission.

    PubMed

    Livengood, Timothy A; Deming, L Drake; A'hearn, Michael F; Charbonneau, David; Hewagama, Tilak; Lisse, Carey M; McFadden, Lucy A; Meadows, Victoria S; Robinson, Tyler D; Seager, Sara; Wellnitz, Dennis D

    2011-11-01

    NASA's EPOXI mission observed the disc-integrated Earth and Moon to test techniques for reconnoitering extrasolar terrestrial planets, using the Deep Impact flyby spacecraft to observe Earth at the beginning and end of Northern Hemisphere spring, 2008, from a range of ∼1/6 to 1/3 AU. These observations furnish high-precision and high-cadence empirical photometry and spectroscopy of Earth, suitable as "ground truth" for numerically simulating realistic observational scenarios for an Earth-like exoplanet with finite signal-to-noise ratio. Earth was observed at near-equatorial sub-spacecraft latitude on 18-19 March, 28-29 May, and 4-5 June (UT), in the range of 372-4540 nm wavelength with low visible resolving power (λ/Δλ=5-13) and moderate IR resolving power (λ/Δλ=215-730). Spectrophotometry in seven filters yields light curves at ∼372-948 nm filter-averaged wavelength, modulated by Earth's rotation with peak-to-peak amplitude of ≤20%. The spatially resolved Sun glint is a minor contributor to disc-integrated reflectance. Spectroscopy at 1100-4540 nm reveals gaseous water and carbon dioxide, with minor features of molecular oxygen, methane, and nitrous oxide. One-day changes in global cloud cover resulted in differences between the light curve beginning and end of ≤5%. The light curve of a lunar transit of Earth on 29 May is color-dependent due to the Moon's red spectrum partially occulting Earth's relatively blue spectrum. The "vegetation red edge" spectral contrast observed between two long-wavelength visible/near-IR bands is ambiguous, not clearly distinguishing between the verdant Earth diluted by cloud cover versus the desolate mineral regolith of the Moon. Spectrophotometry in at least one other comparison band at short wavelength is required to distinguish between Earth-like and Moon-like surfaces in reconnaissance observations. However, measurements at 850 nm alone, the high-reflectance side of the red edge, could be sufficient to

  15. Another Earth 2.0? Not So Fast.

    PubMed

    Schulze-Makuch, Dirk; Guinan, Edward

    2016-11-01

    The number of confirmed exoplanets now exceeds 3000, with an additional nearly 5000 exoplanet candidates awaiting confirmation in the NASA Exoplanet Archive ( 2016 ). Nearly weekly we hear about the detection of a new exoplanet similar in mass to Earth and located in the so-called habitable zone around its host star. The excitement is understandable given our desire to find a second Earth. However, the excitement should not lead to an over-interpretation of the findings, because the claim can only be to have some crude similarity to Earth based on a few selected geophysical parameters. Only a very small fraction of these planets will actually be Earth-like. Earth-like would imply multiple environmental habitats and presence of a sizable biosphere and complex ecosystems, without which Earth, as we experience it, would not exist. Thus, it should be clearly communicated to the public that we are probably still many years away from having the technological capability to detect an Earth-like planet or Earth 2.0 with adequate certainty. Key Words: Habitable zone-Second Earth-Habitable planet-Habitability-Life. Astrobiology 16, 817-821.

  16. Deep Space Earth Observations from DSCOVR

    NASA Astrophysics Data System (ADS)

    Marshak, A.; Herman, J.

    2018-02-01

    The Deep Space Climate Observatory (DSCOVR) at Sun-Earth L1 orbit observes the full sunlit disk of Earth. There are two Earth science instruments on board DSCOVR — EPIC and NISTAR. We discuss if EPIC and NISAR-like instruments can be used in Deep Space Gateway.

  17. Télèmetre utilisant une diode laser à balayage continu en fréquence et un double interférométre

    NASA Astrophysics Data System (ADS)

    Hafidi, Abdeslam; Pfeiffer, Pierre; Meyrueis, Patrick

    2018-04-01

    This paper, "Télèmetre utilisant une diode laser à balayage continu en fréquence et un double interférométre," was presented as part of International Conference on Space Optics—ICSO 1997, held in Toulouse, France.

  18. EOS Reference Handbook 1999: A Guide to NASA's Earth Science Enterprise and the Earth Observing System

    NASA Technical Reports Server (NTRS)

    King, M. D. (Editor); Greenstone, R. (Editor)

    2000-01-01

    The content of this handbook includes Earth Science Enterprise; The Earth Observing System; EOS Data and Information System (EOSDIS); Data and Information Policy; Pathfinder Data Sets; Earth Science Information Partners and the Working Prototype-Federation; EOS Data Quality: Calibration and Validation; Education Programs; International Cooperation; Interagency Coordination; Mission Elements; EOS Instruments; EOS Interdisciplinary Science Investigations; and Points-of-Contact.

  19. Optimal design of near-Earth asteroid sample-return trajectories in the Sun-Earth-Moon system

    NASA Astrophysics Data System (ADS)

    He, Shengmao; Zhu, Zhengfan; Peng, Chao; Ma, Jian; Zhu, Xiaolong; Gao, Yang

    2016-08-01

    In the 6th edition of the Chinese Space Trajectory Design Competition held in 2014, a near-Earth asteroid sample-return trajectory design problem was released, in which the motion of the spacecraft is modeled in multi-body dynamics, considering the gravitational forces of the Sun, Earth, and Moon. It is proposed that an electric-propulsion spacecraft initially parking in a circular 200-km-altitude low Earth orbit is expected to rendezvous with an asteroid and carry as much sample as possible back to the Earth in a 10-year time frame. The team from the Technology and Engineering Center for Space Utilization, Chinese Academy of Sciences has reported a solution with an asteroid sample mass of 328 tons, which is ranked first in the competition. In this article, we will present our design and optimization methods, primarily including overall analysis, target selection, escape from and capture by the Earth-Moon system, and optimization of impulsive and low-thrust trajectories that are modeled in multi-body dynamics. The orbital resonance concept and lunar gravity assists are considered key techniques employed for trajectory design. The reported solution, preliminarily revealing the feasibility of returning a hundreds-of-tons asteroid or asteroid sample, envisions future space missions relating to near-Earth asteroid exploration.

  20. EarthRef.org: Exploring aspects of a Cyber Infrastructure in Earth Science and Education

    NASA Astrophysics Data System (ADS)

    Staudigel, H.; Koppers, A.; Tauxe, L.; Constable, C.; Helly, J.

    2004-12-01

    EarthRef.org is the common host and (co-) developer of a range of earth science databases and IT resources providing a test bed for a Cyberinfrastructure in Earth Science and Education (CIESE). EarthRef.org data base efforts include in particular the Geochemical Earth Reference Model (GERM), the Magnetics Information Consortium (MagIC), the Educational Resources for Earth Science Education (ERESE) project, the Seamount Catalog, the Mid-Ocean Ridge Catalog, the Radio-Isotope Geochronology (RiG) initiative for CHRONOS, and the Microbial Observatory for Fe oxidizing microbes on Loihi Seamount (FeMO; the most recent development). These diverse databases are developed under a single database umbrella and webserver at the San Diego Supercomputing Center. All the data bases have similar structures, with consistent metadata concepts, a common database layout, and automated upload wizards. Shared resources include supporting databases like an address book, a reference/publication catalog, and a common digital archive making database development and maintenance cost-effective, while guaranteeing interoperability. The EarthRef.org CIESE provides a common umbrella for synthesis information as well as sample-based data, and it bridges the gap between science and science education in middle and high schools, validating the potential for a system wide data infrastructure in a CIESE. EarthRef.org experiences have shown that effective communication with the respective communities is a key part of a successful CIESE facilitating both utility and community buy-in. GERM has been particularly successful at developing a metadata scheme for geochemistry and in the development of a new electronic journal (G-cubed) that has made much progress in data publication and linkages between journals and community data bases. GERM also has worked, through editors and publishers, towards interfacing databases with the publication process, to accomplish a more scholarly and database friendly data

  1. Time variations in the Earth's gravity field

    NASA Astrophysics Data System (ADS)

    Shum, C. K.; Eanes, R. J.

    1992-01-01

    At the present time, the causes and consequences of changes in the Earth's gravity field due to geophysical and meteorological phenomena are not well understood. The Earth's gravity field represents the complicated distribution of all of the matter that makes up our planet. Its variations are caused by the motions of the solid Earth interacting with the gravitational attraction of the Sun and the Moon (tides) and with the Earth's atmosphere, oceans, polar ice caps and groundwater due to changing weather patterns. These variations influence the rotation of the Earth, alter the orbits of Earth satellites, cause sea level fluctuations, and indirectly affect the global climate pattern.

  2. Skylab Explores the Earth.

    ERIC Educational Resources Information Center

    National Aeronautics and Space Administration, Washington, DC.

    This book describes the Skylab 4 Earth Explorations Project. Photographs of the earth taken by the Skylab astronauts are reproduced here and accompanied by an analytical and explanatory text. Some of the geological and geographical topics covered are: (1) global tectonics - some geological analyses of observations and photographs from Skylab; (2)…

  3. Séchage d'un enduit pigmenté avec application à l'étude d'une couche papetière

    NASA Astrophysics Data System (ADS)

    Bernada, P.; Bruneau, D.

    1996-07-01

    Paper color coating drying is investigated from several experimental view points which include drying kinetics and time evolution of moisture content profiles, pore size distribution in the dried coating, and natural binder (starch) distribution in the dried coating. A study of the effects of drying conditions on those experimental parameters is carried out. Furthermore, gelification and consolidation characteristic moisture contents of the coating are determined using a graphical approach. Le séchage d'un enduit pigmenté à l'usage d'une couche papetière est absorbé sous diverts aspects : cinétiques de séchage et évolution temporelle des profils de teneur en eau, profils de répartition de la taille des pores dans la couche séchée, et répartition finale d'un liant hydrophile de la sauce de couchage (amidon). Les conséquences des conditions de séchage sur ces paramètres expérimentaux sont mises en évidence. De plus, les teneurs en eau caractéristiques de gélification et consolidation de la sauce de couchage sont obtenues par une approche graphique.

  4. iSTEM: Celebrating Earth Day with Sustainability

    ERIC Educational Resources Information Center

    Sibley, Amanda; Kurz, Terri L.

    2014-01-01

    Earth Day is celebrated annually on April 22. Teachers often commemorate Earth Day with their classes by planting trees, discussing important conservation topics (such as recycling or preventing pollution), and encouraging students to take care of planet Earth. To promote observance of Earth Day in an intermediate elementary school classroom, this…

  5. General Education Engagement in Earth and Planetary Science through an Earth-Mars Analog Curriculum

    NASA Astrophysics Data System (ADS)

    Chan, M. A.; Kahmann-Robinson, J. A.

    2012-12-01

    The successes of NASA rovers on Mars and new remote sensing imagery at unprecedented resolution can awaken students to the valuable application of Earth analogs to understand Mars processes and the possibilities of extraterrestrial life. Mars For Earthlings (MFE) modules and curriculum are designed as general science content introducing a pedagogical approach of integrating Earth science principles and Mars imagery. The content can be easily imported into existing or new general education courses. MFE learning modules introduce students to Google Mars and JMARS software packages and encourage Mars imagery analysis to predict habitable environments on Mars drawing on our knowledge of extreme environments on Earth. "Mars Mission" projects help students develop teamwork and presentation skills. Topic-oriented module examples include: Remote Sensing Mars, Olympus Mons and Igneous Rocks, Surface Sculpting Forces, and Extremophiles. The learning modules package imagery, video, lab, and in-class activities for each topic and are available online for faculty to adapt or adopt in courses either individually or collectively. A piloted MFE course attracted a wide range of non-majors to non-degree seeking senior citizens. Measurable outcomes of the piloted MFE curriculum were: heightened enthusiasm for science, awareness of NASA programs, application of Earth science principles, and increased science literacy to help students develop opinions of current issues (e.g., astrobiology or related government-funded research). Earth and Mars analog examples can attract and engage future STEM students as the next generation of earth, planetary, and astrobiology scientists.

  6. Geology, Geochronology, and EarthScope: The EarthScope AGeS Program and a new idea for a 4D Earth Initiative

    NASA Astrophysics Data System (ADS)

    Flowers, R. M.; Arrowsmith, R.; Metcalf, J. R.; Rittenour, T. M.; Schoene, B.; Hole, J. A.; Pavlis, T. L.; Wagner, L. S.; Whitmeyer, S. J.; Williams, M. L.

    2015-12-01

    The EarthScope AGeS (Awards for Geochronology Student Research) program is a multi-year educational initiative aimed at enhancing interdisciplinary, innovative, and high-impact science by promoting training and new interactions between students, scientists, and geochronology labs at different institutions. The program offers support of up to $10,000 for graduate students to collect and interpret geochronology data that contribute to EarthScope science targets through visits to participating geochronology labs (www.earthscope.org/geochronology). The program was launched by a 2-day short course held before the 2014 National GSA meeting in Vancouver, at which 16 geochronology experts introduced 43 participants to the basic theory and applications of geochronology methods. By the first proposal submission deadline in spring 2015, 33 labs representing a broad range of techniques had joined the program by submitting lab plans that were posted on the EarthScope website. The lab plans provide information about preparation, realistic time frames for visits, and analytical costs. In the first year of the program, students submitted 47 proposals from 32 different institutions. Proposals were ranked by an independent panel, 10 were funded, and research associated with these projects is currently underway. The next proposal deadline will be held in spring 2016. The 4D-Earth initiative is an idea for a natural successor to the EarthScope program aimed at expanding the primarily 3D geophysical focus that captured a snapshot of present day North America into the 4th dimension of time (hence the connection to the prototypical AGeS program), and illuminating the crustal component that was below the resolution of much of the USArray image. Like EarthScope, the notion is that this initiative would integrate new infrastructure and usher in a new way of doing science. The overarching scientific motivation is to develop a Community Geologic Model for the 4-D Evolution of the North

  7. Earth Sciences Division

    NASA Astrophysics Data System (ADS)

    1991-06-01

    This Annual Report presents summaries of selected representative research activities grouped according to the principal disciplines of the Earth Sciences Division: Reservoir Engineering and Hydrogeology, Geology and Geochemistry, and Geophysics and Geomechanics. Much of the Division's research deals with the physical and chemical properties and processes in the earth's crust, from the partially saturated, low-temperature near-surface environment to the high-temperature environments characteristic of regions where magmatic-hydrothermal processes are active. Strengths in laboratory and field instrumentation, numerical modeling, and in situ measurement allow study of the transport of mass and heat through geologic media -- studies that now include the appropriate chemical reactions and the hydraulic-mechanical complexities of fractured rock systems. Of particular note are three major Division efforts addressing problems in the discovery and recovery of petroleum, the application of isotope geochemistry to the study of geodynamic processes and earth history, and the development of borehole methods for high-resolution imaging of the subsurface using seismic and electromagnetic waves. In 1989, a major DOE-wide effort was launched in the areas of Environmental Restoration and Waste Management. Many of the methods previously developed for and applied to deeper regions of the earth will, in the coming years, be turned toward process definition and characterization of the very shallow subsurface, where man-induced contaminants now intrude and where remedial action is required.

  8. Earth Observation

    NASA Image and Video Library

    2011-06-27

    ISS028-E-009979 (27 June 2011) --- The Massachusetts coastline is featured in this image photographed by an Expedition 28 crew member on the International Space Station. The Crew Earth Observations team at NASA Johnson Space Center sends specific ground targets for photography up to the station crew on a daily basis, but sometimes the crew takes imagery on their own of striking displays visible from orbit. One such display, often visible to the ISS crew due to their ability to look outwards at angles between 0 and 90 degrees, is sunglint on the waters of Earth. Sunglint is caused by sunlight reflecting off of a water surface?much as light reflects from a mirror?directly towards the observer. Roughness variations of the water surface scatter the light, blurring the reflection and producing the typical silvery sheen of the sunglint area. The point of maximum sunglint is centered within Cape Cod Bay, the body of water partially enclosed by the ?hook? of Cape Cod in Massachusetts (bottom). Cape Cod was formally designated a National Seashore in 1966. Sunglint off the water provides sharp contrast with the coastline and the nearby islands of Martha?s Vineyard and Nantucket (lower left), both popular destinations for tourists and summer residents. To the north, rocky Cape Ann extends out into the Atlantic Ocean; the border with New Hampshire is located approximately 30 kilometers up the coast. Further to the west, the eastern half of Long Island, New York is visible emerging from extensive cloud cover over the mid-Atlantic and Midwestern States. Persistent storm tracks had been contributing to record flooding along rivers in the Midwest at the time this image was taken in late June 2011. Thin blue layers of the atmosphere, contrasted against the darkness of space, are visible extending along the Earth?s curvature at top.

  9. Earth Institute at Columbia University ADVANCE Program: Addressing Needs for Women in Earth and Environmental Sciences

    NASA Astrophysics Data System (ADS)

    Bell, R. E.; Cane, M.; Mutter, J.; Miller, R.; Pfirman, S.; Laird, J.

    2004-12-01

    The Earth Institute has received a major NSF ADVANCE grant targeted at increasing the participation and advancement of women scientists and engineers in the Academy through institutional transformation. The Earth Institute at Columbia University includes 9 research institutes including Lamont-Doherty Earth Observatory, Center for Environmental Research and Conservation (CERC), Center for International Earth Science Information Network (CIESIN), International Research Institute (IRI) for Climate Prediction, Earth Engineering Center, NASA-Goddard Institute for Space Studies, Center for Risks and Hazards, Center for Globalization and Sustainable Development, and Center for Global Health and Economic Development and six academic departments including Ecology, Evolution and Environmental Biology (E3B, School of Arts and Sciences), Earth and Environmental Engineering (DEEE, School of Engineering and Applied Sciences), Department of Environmental Health (School of Public Health), Department of Earth and Environmental Sciences (DEES, School of Arts and Sciences), Department of International and Public Affairs (School of International and Policy Affairs), and Barnard College Department of Environmental Science. The Earth Institute at Columbia University's ADVANCE program is based both on a study of the status of women at Columbia and research on the progression of women in science elsewhere. The five major targets of the Columbia ADVANCE program are to (1) change the demographics of the faculty through intelligent hiring practices, (2) provide support to women scientists through difficult life transitions including elder care and adoption or birth of a child, (3) enhance mentoring and networking opportunities, (4) implement transparent promotion procedures and policies, and (5) conduct an institutional self study. The Earth Institute ADVANCE program is unique in that it addresses issues that tend to manifest themselves in the earth and environmental fields, such as extended

  10. Keeping Earth at work: Using thermodynamics to develop a holistic theory of the Earth system

    NASA Astrophysics Data System (ADS)

    Kleidon, Axel

    2010-05-01

    The Earth system is unique among terrestrial planets in that it is maintained in a state far from thermodynamic equilibrium. Practically all processes are irreversible in their nature, thereby producing entropy, and these would act to destroy this state of disequilibrium. In order to maintain disequilibrium in steady state, driving forces are required that perform the work to maintain the Earth system in a state far from equilibrium. To characterize the functioning of the Earth system and the interactions among its subsystems we need to consider all terms of the first and second law of thermodynamics. While the global energy balance is well established in climatology, the global entropy and work balances receive little, if any, attention. Here I will present first steps in developing a holistic theory of the Earth system including quantifications of the relevant terms that is based on the first and second laws of thermodynamics. This theory allows us to compare the significance of different processes in driving and maintaining disequilibrium, allows us to explore interactions by investigating the role of power transfer among processes, and specifically illustrate the significance of life in driving planetary disequilibrium. Furthermore, the global work balance demonstrates the significant impact of human activity and it provides an estimate for the availability of renewable sources of free energy within the Earth system. Hence, I conclude that a holistic thermodynamic theory of the Earth system is not just some academic exercise of marginal use, but essential for a profound understanding of the Earth system and its response to change.

  11. The Crew Earth Observations Experiment: Earth System Science from the ISS

    NASA Technical Reports Server (NTRS)

    Stefanov, William L.; Evans, Cynthia A.; Robinson, Julie A.; Wilkinson, M. Justin

    2007-01-01

    This viewgraph presentation reviews the use of Astronaut Photography (AP) as taken from the International Space Station (ISS) in Earth System Science (ESS). Included are slides showing basic remote sensing theory, data characteristics of astronaut photography, astronaut training and operations, crew Earth observations group, targeting sites and acquisition, cataloging and database, analysis and applications for ESS, image analysis of particular interest urban areas, megafans, deltas, coral reefs. There are examples of the photographs and the analysis.

  12. Earth Observation

    NASA Image and Video Library

    2014-07-19

    ISS040-E-070439 (19 July 2014) --- One of the Expedition 40 crew members aboard the Earth-orbiting International Space Station recorded this July 19 image of wildfires which are plaguing the Northwest and causing widespread destruction. The orbital outpost was flying 223 nautical miles above a point on Earth located at 48.0 degrees north latitude and 116.9 degrees west longitude when the image was exposed. The state of Washington is especially affected by the fires, many of which have been blamed on lightning. This particular fire was part of the Carlton Complex Fire, located near the city of Brewster in north central Washington. The reservoir visible near the center of the image is Banks Lake.

  13. The Near-Earth Plasma Environment

    NASA Technical Reports Server (NTRS)

    Pfaff, Robert F., Jr.

    2012-01-01

    An overview of the plasma environment near the earth is provided. We describe how the near-earth plasma is formed, including photo-ionization from solar photons and impact ionization at high latitudes from energetic particles. We review the fundamental characteristics of the earth's plasma environment, with emphasis on the ionosphere and its interactions with the extended neutral atmosphere. Important processes that control ionospheric physics at low, middle, and high latitudes are discussed. The general dynamics and morphology of the ionized gas at mid- and low-latitudes are described including electrodynamic contributions from wind-driven dynamos, tides, and planetary-scale waves. The unique properties of the near-earth plasma and its associated currents at high latitudes are shown to depend on precipitating auroral charged particles and strong electric fields which map earthward from the magnetosphere. The upper atmosphere is shown to have profound effects on the transfer of energy and momentum between the high-latitude plasma and the neutral constituents. The article concludes with a discussion of how the near-earth plasma responds to magnetic storms associated with solar disturbances.

  14. The Visibility of Earth Transits

    NASA Technical Reports Server (NTRS)

    Castellano, Timothy P.; Doyle, Laurance; McIntosh, Dawn; DeVincenzi, Donald (Technical Monitor)

    2000-01-01

    The recent photometric detection of planetary transits of the solar-like star HD 209458 at a distance of 47 parsecs suggest that transits can reveal the presence of Jupiter-size planetary companions in the solar neighborhood. Recent space-based transit searches have achieved photometric precision within an order of magnitude of that required to detect the much smaller transit signal of an earth-size planet across a solar-size star. Laboratory experiments in the presence of realistic noise sources have shown that CCDs can achieve photometric precision adequate to detect the 9.6 E-5 dimming of the Sun due to a transit of the Earth. Space-based solar irradiance monitoring has shown that the intrinsic variability of the Sun would not preclude such a detection. Transits of the Sun by the Earth would be detectable by observers that reside within a narrow band of sky positions near the ecliptic plane, if the observers possess current Earth epoch levels of technology and astronomical expertise. A catalog of solar-like stars that satisfy the geometric condition for Earth transit visibility are presented.

  15. Earth System Science Project

    ERIC Educational Resources Information Center

    Rutherford, Sandra; Coffman, Margaret

    2004-01-01

    For several decades, science teachers have used bottles for classroom projects designed to teach students about biology. Bottle projects do not have to just focus on biology, however. These projects can also be used to engage students in Earth science topics. This article describes the Earth System Science Project, which was adapted and developed…

  16. Le TERS, ou comment obtenir une signature chimique à l'échelle nanométrique

    NASA Astrophysics Data System (ADS)

    Hsia, Patrick; Chaigneau, Marc

    2018-02-01

    Le TERS pour tip enhanced raman scattering, est une technique de pointe (dans tous les sens du terme) basée sur l'amplification du signal Raman relative à la résonance de plasmons de surface. Cette technique non-destructive, qui ne nécessite pas de marquage particulier, permet de caractériser un échantillon à l'échelle nanométrique. Le TERS s'impose aujourd'hui pour sonder les propriétés physico-chimiques des nanomatériaux et participer ainsi au développement de nouvelles applications dans le domaine des nanotechnologies.

  17. Another Earth 2.0? Not So Fast

    NASA Astrophysics Data System (ADS)

    Schulze-Makuch, Dirk; Guinan, Edward

    2016-11-01

    The number of confirmed exoplanets now exceeds 3000, with an additional nearly 5000 exoplanet candidates awaiting confirmation in the NASA Exoplanet Archive (2016). Nearly weekly we hear about the detection of a new exoplanet similar in mass to Earth and located in the so-called habitable zone around its host star. The excitement is understandable given our desire to find a second Earth. However, the excitement should not lead to an over-interpretation of the findings, because the claim can only be to have some crude similarity to Earth based on a few selected geophysical parameters. Only a very small fraction of these planets will actually be Earth-like. Earth-like would imply multiple environmental habitats and presence of a sizable biosphere and complex ecosystems, without which Earth, as we experience it, would not exist. Thus, it should be clearly communicated to the public that we are probably still many years away from having the technological capability to detect an Earth-like planet or Earth 2.0 with adequate certainty.

  18. EARTHS (Earth Albedo Radiometer for Temporal Hemispheric Sensing)

    NASA Astrophysics Data System (ADS)

    Ackleson, S. G.; Bowles, J. H.; Mouroulis, P.; Philpot, W. D.

    2018-02-01

    We propose a concept for measuring the hemispherical Earth albedo in high temporal and spectral resolution using a hyperspectral imaging sensor deployed on a lunar satellite, such as the proposed NASA Deep Space Gateway.

  19. Flexible Description and Adaptive Processing of Earth Observation Data through the BigEarth Platform

    NASA Astrophysics Data System (ADS)

    Gorgan, Dorian; Bacu, Victor; Stefanut, Teodor; Nandra, Cosmin; Mihon, Danut

    2016-04-01

    The Earth Observation data repositories extending periodically by several terabytes become a critical issue for organizations. The management of the storage capacity of such big datasets, accessing policy, data protection, searching, and complex processing require high costs that impose efficient solutions to balance the cost and value of data. Data can create value only when it is used, and the data protection has to be oriented toward allowing innovation that sometimes depends on creative people, which achieve unexpected valuable results through a flexible and adaptive manner. The users need to describe and experiment themselves different complex algorithms through analytics in order to valorize data. The analytics uses descriptive and predictive models to gain valuable knowledge and information from data analysis. Possible solutions for advanced processing of big Earth Observation data are given by the HPC platforms such as cloud. With platforms becoming more complex and heterogeneous, the developing of applications is even harder and the efficient mapping of these applications to a suitable and optimum platform, working on huge distributed data repositories, is challenging and complex as well, even by using specialized software services. From the user point of view, an optimum environment gives acceptable execution times, offers a high level of usability by hiding the complexity of computing infrastructure, and supports an open accessibility and control to application entities and functionality. The BigEarth platform [1] supports the entire flow of flexible description of processing by basic operators and adaptive execution over cloud infrastructure [2]. The basic modules of the pipeline such as the KEOPS [3] set of basic operators, the WorDeL language [4], the Planner for sequential and parallel processing, and the Executor through virtual machines, are detailed as the main components of the BigEarth platform [5]. The presentation exemplifies the development

  20. Evidence for a near-Earth asteroid belt

    NASA Technical Reports Server (NTRS)

    Rabinowitz, D. L.; Gehrels, T.; Scotti, J. V.; Mcmillan, R. S.; Perry, M. L.; Wisniewski, W.; Larson, S. M.; Howell, E. S.; Mueller, B. E. A.

    1993-01-01

    In January 1991, the 0.9-m Spacewatch telescope made the first observation of an asteroid outside Earth's atmosphere but in the neighborhood of the Earth-moon system. Since then, more than 40 Earth-approaching asteroids have been discovered, including 13 smaller than 50 m. Using these data, one of us has shown that there is an excess of Earth-approaching asteroids with diameters less than 50 m, relative to the population inferred from the distribution of larger objects. Here we argue that these smaller objects - characterized by low eccentricities, widely ranging inclinations and unusual spectral properties - form a previously undetected asteroid belt concentrated near Earth. The recent discovery of additional small Earth-approaching asteroids supports this conclusion.

  1. Understanding our Changing Planet: NASA's Earth Science Enterprise

    NASA Technical Reports Server (NTRS)

    Forehand, Lon; Griner, Charlotte (Editor); Greenstone, Renny (Editor)

    1999-01-01

    NASA has been studying the Earth and its changing environment by observing the atmosphere, oceans, land, ice, and snow and their influence on climate and weather since the agency's creation. This study has lead to a new approach to understanding the interaction of the Earth's systems, Earth System Science. The Earth Science Enterprise, NASA's comprehensive program for Earth System Science, uses satellites and other tools to intensively study the Earth. The Earth Science Enterprise has three main components: (1) a series of Earth-observing satellites, (2) an advanced data system and (3) teams of scientist who study the data. Key areas of study include: (1) clouds, (2) water and energy cycles, (3) oceans, (4) chemistry of the atmosphere, (5) land surface, water and ecosystems processes; (6) glaciers and polar ice sheets, and (7) the solid earth.

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

    PubMed Central

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

    2014-01-01

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

  3. Satellite-tracking and Earth dynamics research programs

    NASA Technical Reports Server (NTRS)

    1983-01-01

    Tracking of LAGEOS for polar motion and Earth rotation studies and for other geophysical investigations, including crustal dynamics, Earth and ocean tides, and the general development of precision orbit determination continues. The BE-C and Starlette satellites were tracked for refined determinations of station coordinates and the Earth's gravity field and for studies of solid Earth dynamics.

  4. 3D-model: Earth's seasons

    NASA Astrophysics Data System (ADS)

    Meirlaen, Koen

    2017-04-01

    A lot of subjects in geography and geology are linked to the seasons of the earth. Most of the students think that the earth's seasons are caused by the differences in the distance from the sun throughout the year. So as a teacher I tried year after year to explain the motion of the earth around the sun. Even when I used animations/movies/… it still seemed difficult for the students to understand the 3D-situation. Most of the animations only show the start of every season but it's important to demonstrate to the students the motion of the earth during a year so they can see that the tilt of our planet causes the seasons. The earth's axis is tilted by 23.4 degrees to the plane in which it travels around the sun, the ecliptic. So I started to work on a 3D-model on a scale to use in a classroom. It measures approximately 2m by 1m. You can buy all the materials in DIY-shop for less than € 100: wooden plank, lamp, styrofoam spheres (= earth), … I have been using the model for over 4 years now and it's very nice to work with. You can involve the students more and let them investigate for themselves what causes the seasons. The model demonstrates the start of every season, why it is dark for several months in several places on Earth. They can draw the positions of the Tropic of Cancer, Tropic of Capricorn, Arctic Circle and Antarctic Circle on the styrofoam spheres. Also the difference between day and night is well shown on the globes. A lot of subjects in geography and geology are linked to the seasons of the earth: the changes in weather, ocean currents, winds, tropical storms, vegetation, fauna and flora, hours of daylight, … even economy, migration and social health. This way the model can be used in many lessons during the year. The poster session will demonstrate how you can make the 3D-model, some exercises, …

  5. Earth Day 2018 Activities

    NASA Image and Video Library

    2018-04-17

    During the annual Earth Day celebration at the Kennedy Space Center Visitor Complex, Shari Blissett-Clark of the Florida Bat Conservancy displays one of the mammals. The event took place during the annual Earth Day celebration at the Kennedy Space Center Visitor Complex, guests have an opportunity to learn more about energy awareness, the environment and sustainability.

  6. Introducing Earth's Orbital Eccentricity

    ERIC Educational Resources Information Center

    Oostra, Benjamin

    2015-01-01

    Most students know that planetary orbits, including Earth's, are elliptical; that is Kepler's first law, and it is found in many science textbooks. But quite a few are mistaken about the details, thinking that the orbit is very eccentric, or that this effect is somehow responsible for the seasons. In fact, the Earth's orbital eccentricity is…

  7. The Earth Needs You!

    ERIC Educational Resources Information Center

    Curriculum Review, 2008

    2008-01-01

    Celebrated annually on April 22, schools and communities organize numerous activities during Earth Day to promote awareness. To help teachers plan their own initiatives and to learn more about what is happening around the world, they can join the Earth Day Network at: http://network.earthday.net/. Once they have joined, they can create a webpage…

  8. NASA's Earth science flight program status

    NASA Astrophysics Data System (ADS)

    Neeck, Steven P.; Volz, Stephen M.

    2010-10-01

    NASA's strategic goal to "advance scientific understanding of the changing Earth system to meet societal needs" continues the agency's legacy of expanding human knowledge of the Earth through space activities, as mandated by the National Aeronautics and Space Act of 1958. Over the past 50 years, NASA has been the world leader in developing space-based Earth observing systems and capabilities that have fundamentally changed our view of our planet and have defined Earth system science. The U.S. National Research Council report "Earth Observations from Space: The First 50 Years of Scientific Achievements" published in 2008 by the National Academy of Sciences articulates those key achievements and the evolution of the space observing capabilities, looking forward to growing potential to address Earth science questions and enable an abundance of practical applications. NASA's Earth science program is an end-to-end one that encompasses the development of observational techniques and the instrument technology needed to implement them. This includes laboratory testing and demonstration from surface, airborne, or space-based platforms; research to increase basic process knowledge; incorporation of results into complex computational models to more fully characterize the present state and future evolution of the Earth system; and development of partnerships with national and international organizations that can use the generated information in environmental forecasting and in policy, business, and management decisions. Currently, NASA's Earth Science Division (ESD) has 14 operating Earth science space missions with 6 in development and 18 under study or in technology risk reduction. Two Tier 2 Decadal Survey climate-focused missions, Active Sensing of CO2 Emissions over Nights, Days and Seasons (ASCENDS) and Surface Water and Ocean Topography (SWOT), have been identified in conjunction with the U.S. Global Change Research Program and initiated for launch in the 2019

  9. Rare Earth Element Mines, Deposits, and Occurrences

    USGS Publications Warehouse

    Orris, Greta J.; Grauch, Richard I.

    2002-01-01

    Data on rare earth (including yttrium) mines, deposits, and occurrences were compiled as part of an effort by the USGS and the University of Arizona Center for Mineral Resources to summarize current knowledge on the supply and demand outlook and related topics for this group of elements. Economic competition and environmental concerns are increasingly constraining the mining and processing of rare earths from the Mountain Pass mine in California. For many years, the deposit at Mountain Pass was the world's dominant source of rare earth elements and the United States was essentially self-sufficient. Starting approximately 10 years ago, the U.S. has become increasingly dependent (> 90 percent of separated rare earths) upon imports from China, now the dominant source of rare earths. A knowledge of the known economic and noneconomic sources of rare earths is basic to evaluating the outlook for rare earth supply and associated issues.

  10. Galileo: Earth avoidance study report

    NASA Technical Reports Server (NTRS)

    Mitchell, R. T.

    1988-01-01

    The 1989 Galileo mission to Jupiter is based on a VEEGA (Venus Earth Earth-Gravity Assist) trajectory which uses two flybys of Earth and one of Venus to achieve the necessary energy and shaping to reach Jupiter. These encounters are needed because the Centaur upper stage is not now being used on this mission. Since the Galileo spacecraft uses radioisotope thermoelectric generators (RTGs) for electrical power, the question arises as to whether there is any chance of an inadvertent atmospheric entry of the spacecraft during either of the two Earth flybys. A study was performed which determined the necessary actions, in both spacecraft and trajectory design as well as in operations, to insure that the probability of such reentry is made very small, and to provide a quantitative assessment of the probability of reentry.

  11. Earth system science: A program for global change

    NASA Technical Reports Server (NTRS)

    1989-01-01

    The Earth System Sciences Committee (ESSC) was appointed to consider directions for the NASA Earth-sciences program, with the following charge: review the science of the Earth as a system of interacting components; recommend an implementation strategy for Earth studies; and define the role of NASA in such a program. The challenge to the Earth system science is to develop the capability to predict those changes that will occur in the next decade to century, both naturally and in response to human activity. Sustained, long-term measurements of global variables; fundamental descriptions of the Earth and its history; research foci and process studies; development of Earth system models; an information system for Earth system science; coordination of Federal agencies; and international cooperation are examined.

  12. Spacewatch discovery of near-Earth asteroids

    NASA Technical Reports Server (NTRS)

    Gehrels, Tom

    1992-01-01

    Our overall scientific goal is to survey the solar system to completion - that is, to find the various populations and to study their statistics, interrelations, and origins. The practical benefit to SERC is that we are finding Earth-approaching asteroids that are accessible for mining. Our system can detect Earth-approachers in the 1-km size range even when they are far away, and can detect smaller objects when they are moving rapidly past Earth. Until Spacewatch, the size range of 6-300 meters in diameter for the near-Earth asteroids was unexplored. This important region represents the transition between the meteorites and the larger observed near-Earth asteroids. One of our Spacewatch discoveries, 1991 VG, may be representative of a new orbital class of object. If it is really a natural object, and not man-made, its orbital parameters are closer to those of the Earth than we have seen before; its delta V is the lowest of all objects known thus far. We may expect new discoveries as we continue our surveying, with fine-tuning of the techniques.

  13. Behaviour of Rare Earth Elements during the Earth's core formation

    NASA Astrophysics Data System (ADS)

    Faure, Pierre; Bouhifd, Mohamed Ali; Boyet, Maud; Hammouda, Tahar; Manthilake, Geeth

    2017-04-01

    Rare Earth Elements (REE) are classified in the refractory group, which means that they have a high temperature condensation and their volatility-controlled fractionation is limited to high-temperature processes. Anomalies have been measured for Eu, Yb and Sm, which are the REE with the lowest condensation temperatures in CAIs and chondrules (e.g. [1]). REE are particularly abundant in the sulfides of enstatite chondrites, 100 to 1000 times the CI value [e.g. 2,3], proving that these elements are not strictly lithophile under extremely reducing conditions. However by investigating experimentally the impact of Earth's core formation on the behavior of Sm and Nd, we have shown the absence of fractionation between Sm and Nd during the segregation of the metallic phase [4]. Recently, Wohlers and Wood [5] proposed that Nd and Sm could be fractionated in presence of a S-rich alloy phase. However, their results were obtained at pressure and temperature conditions below the plausible conditions of the Earth's core formation. Clearly, large pressure range needs to be covered before well-constrained model can be expected. Furthermore, our preliminary metal-silicate partitioning results show that Ce and Eu have higher metal/silicate partition coefficients than their neighboring elements, and that the presence of sulphur enhances the relative difference between partition coefficients. In this presentation, we will present and discuss new metal-silicate partition coefficients of all REE at a deep magma ocean at pressures ranging from those of the uppermost upper mantle ( 5 GPa) to a maximum pressure expected in the range of 20 GPa, temperatures ranging from 2500 to about 3000 K, and oxygen fugacities within IW-1 to IW-5 (1 to 5 orders of magnitude lower than the iron-wüstite buffer). We will discuss the effect of S, as well as the effect of H2O on the behaviour of REE during the Earth's core formation: recent models suggest that contrary to currently accepted beliefs, the

  14. Earth: A Ringed Planet?

    NASA Astrophysics Data System (ADS)

    Hancock, L. O.; Povenmire, H.

    2010-12-01

    Among the most beautiful findings of the Space Age have been the discoveries of planetary rings. Not only Saturn but also Jupiter, Uranus and Neptune have rings; Saturn’s ring system has structures newly discovered; even Saturn's moon Rhea itself has a ring. All these are apparently supplied by material from the planetary moons (Rhea's ring by Rhea itself). The question naturally arises, why should the Earth not have a ring, and on the other hand, if it does, why has it not been observed? No rings have yet been observed in the inner solar system, but after all, rings in the inner solar system might simply tend to be fainter and more transient than those of the outer solar system: the inner solar system is more affected by the solar wind, and the Sun’s perturbing gravitational influence is greater. J.A. O’Keefe first suggested (1980) that Earth might have a ring system of its own. An Earth ring could account for some climate events. O’Keefe remarked that formation or thickening of a ring system in Earth’s equatorial plane could drive glaciation by deepening the chill of the winter hemisphere. (It is very well established that volcanic dust is an effective agent for the extinction of sunlight; this factor can be overwhelmingly apparent in eclipse observations.) O’Keefe died in 2000 and the speculation was not pursued, but the idea of an Earth ring has a prima facie reasonableness that calls for its renewed consideration. The program of this note is to hypothesize that, as O’Keefe proposed: (a) an Earth ring system exists; (b) it affects Earth's weather and climate; (c) the tektite strewn fields comprise filaments of the ring fallen to Earth's surface on various occasions of disturbance by comets or asteroids. On this basis, and drawing on the world's weather records, together with the Twentieth Century Reanalysis by NCEP/CIRES covering the period 1870-2010 and the geology of the tektite strewn fields, we herein propose the hypothesized Earth ring

  15. Earth Systems Science: An Analytic Framework

    ERIC Educational Resources Information Center

    Finley, Fred N.; Nam, Younkeyong; Oughton, John

    2011-01-01

    Earth Systems Science (ESS) is emerging rapidly as a discipline and is being used to replace the older earth science education that has been taught as unrelated disciplines--geology, meteorology, astronomy, and oceanography. ESS is complex and is based on the idea that the earth can be understood as a set of interacting natural and social systems.…

  16. Center for Space and Earth Science

    Science.gov Websites

    Search Site submit Los Alamos National LaboratoryCenter for Space and Earth Science Part of the Partnerships NSEC » CSES Center for Space and Earth Science High quality, cutting-edge science in the areas of astrophysics, space physics, solid planetary geoscience, and Earth systems Contact Director Reiner Friedel (505

  17. Rare Earths; The Fraternal Fifteen (Rev.)

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

    Gschneidner, Jr., Karl A.

    1966-01-01

    Rare earths are a set of 15 elements: lanthanum, cerium, praseodymium, neodymium, promethium, samarium, europium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium and lutetium. They are not rare and not earths; they are metals and quite abundant. They are studied to develop commercial products which are beneficial to mankind, and because some rare earths are important to fission products.

  18. Earth Science Literacy: Building Community Consensus

    NASA Astrophysics Data System (ADS)

    Wysession, M.; Ladue, N.; Budd, D.; Campbell, K.; Conklin, M.; Lewis, G.; Raynolds, R.; Ridky, R.; Ross, R.; Taber, J.; Tewksbury, B.; Tuddenham, P.

    2008-12-01

    During 2008, the Earth Sciences Literacy Initiative (ESLI) constructed a framework of earth science "Big Ideas" and "Supporting Concepts". Following the examples of recent literacy efforts in the ocean, atmosphere and climate research communities, ESLI has distilled the fundamental understandings of the earth science community into a document that all members of the community will be able to refer to when working with educators, policy-makers, the press and members of the general public. This document is currently in draft form for review and will be published for public distribution in 2009. ESLI began with the construction of an organizing committee of a dozen people who represent a wide array of earth science backgrounds. This group then organized and ran two workshops in 2008: a 2-week online content workshop and a 3-day intensive writing workshop. For both workshops, participants were chosen so as to cover the full breadth of earth science related to the solid earth, surficial processes, and fresh-water hydrology. The asynchronous online workshop included 350 scientists and educators participating from around the world and was a powerful way to gather ideas and information while retaining a written record of all interactions. The writing workshop included 35 scientists, educators and agency representatives to codify the extensive input of the online workshop. Since September, 2008, drafts of the ESLI literacy framework have been circulated through many different channels to make sure that the document accurately reflects the current understandings of earth scientists and to ensure that it is widely accepted and adopted by the earth science communities.

  19. USGEO Common Framework For Earth Observation Data

    NASA Astrophysics Data System (ADS)

    Walter, J.; de la Beaujardiere, J.; Bristol, S.

    2015-12-01

    The United States Group on Earth Observations (USGEO) Data Management Working Group (DMWG) is an interagency body established by the White House Office of Science and Technology Policy (OSTP). The primary purpose of this group is to foster interagency cooperation and collaboration for improving the life cycle data management practices and interoperability of federally held earth observation data consistent with White House documents including the National Strategy for Civil Earth Observations, the National Plan for Civil Earth Observations, and the May 2013 Executive Order on Open Data (M-13-13). The members of the USGEO DMWG are working on developing a Common Framework for Earth Observation Data that consists of recommended standards and approaches for realizing these goals as well as improving the discoverability, accessibility, and usability of federally held earth observation data. These recommendations will also guide work being performed under the Big Earth Data Initiative (BEDI). This talk will summarize the Common Framework, the philosophy behind it, and next steps forward.

  20. Earth Observation

    NASA Image and Video Library

    2013-08-20

    Earth observation taken during day pass by an Expedition 36 crew member on board the International Space Station (ISS). Per Twitter message: Looking southwest over northern Africa. Libya, Algeria, Niger.

  1. Earth and ocean modeling

    NASA Technical Reports Server (NTRS)

    Knezovich, F. M.

    1976-01-01

    A modular structured system of computer programs is presented utilizing earth and ocean dynamical data keyed to finitely defined parameters. The model is an assemblage of mathematical algorithms with an inherent capability of maturation with progressive improvements in observational data frequencies, accuracies and scopes. The Eom in its present state is a first-order approach to a geophysical model of the earth's dynamics.

  2. Non-rocket Earth-Moon transport system

    NASA Astrophysics Data System (ADS)

    Bolonkin, Alexander

    2003-06-01

    This paper proposes a new transportation system for travel between Earth and Moon. This transportation system uses mechanical energy transfer and requires only minimal energy, using an engine located on Earth. A cable directly connects a pole of the Earth through a drive station to the lunar surface_ The equation for an optimal equal stress cable for complex gravitational field of Earth-Moon has been derived that allows significantly lower cable masses. The required strength could be provided by cables constructed of carbon nanotubes or carbon whiskers. Some of the constraints on such a system are discussed.

  3. Aqua Satellite Orbiting Earth Artist Concept

    NASA Image and Video Library

    2002-05-08

    NASA Aqua satellite carries six state-of-the-art instruments in a near-polar low-Earth orbit. Aqua is seen in this artist concept orbiting Earth. The six instruments are the Atmospheric Infrared Sounder (AIRS), the Advanced Microwave Sounding Unit (AMSU-A), the Humidity Sounder for Brazil (HSB), the Advanced Microwave Scanning Radiometer for EOS (AMSR-E), the Moderate Resolution Imaging Spectroradiometer (MODIS), and Clouds and the Earth's Radiant Energy System (CERES). Each has unique characteristics and capabilities, and all six serve together to form a powerful package for Earth observations. http://photojournal.jpl.nasa.gov/catalog/PIA18156

  4. The Earth is flat when personally significant experiences with the sphericity of the Earth are absent.

    PubMed

    Carbon, Claus-Christian

    2010-07-01

    Participants with personal and without personal experiences with the Earth as a sphere estimated large-scale distances between six cities located on different continents. Cognitive distances were submitted to a specific multidimensional scaling algorithm in the 3D Euclidean space with the constraint that all cities had to lie on the same sphere. A simulation was run that calculated respective 3D configurations of the city positions for a wide range of radii of the proposed sphere. People who had personally experienced the Earth as a sphere, at least once in their lifetime, showed a clear optimal solution of the multidimensional scaling (MDS) routine with a mean radius deviating only 8% from the actual radius of the Earth. In contrast, the calculated configurations for people without any personal experience with the Earth as a sphere were compatible with a cognitive concept of a flat Earth. 2010 Elsevier B.V. All rights reserved.

  5. The young age of Earth

    NASA Astrophysics Data System (ADS)

    Zhang, Youxue

    1998-09-01

    Patterson (1956) established that the age of Earth is close to that of meteorites. Over the last 20 years, workers argued for younger age for core differentiation based on Pb-Pb model ages and tungsten isotopic data and for gas retention based on I-Xe modeling. However, disagreement is abundant, and the young age of Earth has not been widely accepted. In this work, I examine all radiogenic noble gases in the atmosphere and use a model-independent approach and total inversion to show that (1) the Xe-closure age of Earth is 109 ± 23 million years younger than the formation of meteorite Bjurbole (˜4560 Ma) and (2) all radiogenic components of noble gases in the atmosphere can be quantitatively accounted for by production and degassing ˜60% of the bulk silicate earth. The agreement between the 129I- 129Xe clock and 244Pu- 238U- 136Xe- 134Xe- 132Xe- 131Xe clock suggests that the volatility of iodine does not affect the 129I- 129Xe clock. Earth's Xe-closure age is 4.45 ± 0.02 Ga, consistent with the model age of Pb and the 146Sm- 142Nd, 147Sm- 143Nd and 182Hf- 182W systematics. On the basis of the consistency of these ages, 4.45 ± 0.02 Ga probably represents the time when the last Martian-sized planetesimal hit Earth and reinitialized the global clocks.

  6. The Earth and Environmental Systems Podcast, and the Earth Explorations Video Series

    NASA Astrophysics Data System (ADS)

    Shorey, C. V.

    2015-12-01

    The Earth and Environmental Systems Podcast, a complete overview of the theoretical basics of Earth Science in 64 episodes, was completed in 2009, but has continued to serve the worldwide community as evidenced by listener feedback (e.g. "I am a 65 year old man. I have been retired for awhile and thought that retirement would be nothing more than waiting for the grave. However I want to thank you for your geo podcasts. They have given me a new lease on life and taught me a great deal." - FP, 2015). My current project is a video series on the practical basics of Earth Science titled "Earth Explorations". Each video is under 12 minutes long and tackles a major Earth Science concept. These videos go beyond a talking head, or even voice-over with static pictures or white-board graphics. Moving images are combined with animations created with Adobe After Effects, and aerial shots using a UAV. The dialog is scripted in a way to make it accessible at many levels, and the episodes as they currently stand have been used in K-12, and Freshman college levels with success. Though these videos are made to be used at this introductory level, they are also designed as remedial episodes for upper level classes, freeing up time given to review for new content. When completed, the series should contain close to 200 episodes, and this talk will cover the full range of resources I have produced, plan to produce, and how to access these resources. Both resources are available on iTunesU, and the videos are also available on YouTube.

  7. Jupyter meets Earth: Creating Comprehensible and Reproducible Scientific Workflows with Jupyter Notebooks and Google Earth Engine

    NASA Astrophysics Data System (ADS)

    Erickson, T.

    2016-12-01

    Deriving actionable information from Earth observation data obtained from sensors or models can be quite complicated, and sharing those insights with others in a form that they can understand, reproduce, and improve upon is equally difficult. Journal articles, even if digital, commonly present just a summary of an analysis that cannot be understood in depth or reproduced without major effort on the part of the reader. Here we show a method of improving scientific literacy by pairing a recently developed scientific presentation technology (Jupyter Notebooks) with a petabyte-scale platform for accessing and analyzing Earth observation and model data (Google Earth Engine). Jupyter Notebooks are interactive web documents that mix live code with annotations such as rich-text markup, equations, images, videos, hyperlinks and dynamic output. Notebooks were first introduced as part of the IPython project in 2011, and have since gained wide acceptance in the scientific programming community, initially among Python programmers but later by a wide range of scientific programming languages. While Jupyter Notebooks have been widely adopted for general data analysis, data visualization, and machine learning, to date there have been relatively few examples of using Jupyter Notebooks to analyze geospatial datasets. Google Earth Engine is cloud-based platform for analyzing geospatial data, such as satellite remote sensing imagery and/or Earth system model output. Through its Python API, Earth Engine makes petabytes of Earth observation data accessible, and provides hundreds of algorithmic building blocks that can be chained together to produce high-level algorithms and outputs in real-time. We anticipate that this technology pairing will facilitate a better way of creating, documenting, and sharing complex analyses that derive information on our Earth that can be used to promote broader understanding of the complex issues that it faces. http://jupyter.orghttps://earthengine.google.com

  8. Crescent-shaped Earth and Moon

    NASA Technical Reports Server (NTRS)

    1978-01-01

    This picture of a crescent-shaped Earth and Moon -- the first of its kind ever taken by a spacecraft -- was recorded Sept. 18, 1977, by NASA's Voyager 1 when it was 7.25 million miles (11.66 million kilometers) from Earth. The Moon is at the top of the picture and beyond the Earth as viewed by Voyager. In the picture are eastern Asia, the western Pacific Ocean and part of the Arctic. Voyager 1 was directly above Mt. Everest (on the night side of the planet at 25 degrees north latitude) when the picture was taken. The photo was made from three images taken through color filters, then processed by the Jet Propulsion Laboratory's Image Processing Lab. Because the Earth is many times brighter than the Moon, the Moon was artificially brightened by a factor of three relative to the Earth by computer enhancement so that both bodies would show clearly in the print. Voyager 2 was launched Aug. 20, 1977, followed by Voyager 1 on Sept. 5, 1977, en route to encounters at Jupiter in 1979 and Saturn in 1980 and 1981. JPL manages the Voyager mission for NASA.

  9. The Visibility of Earth Transits

    NASA Technical Reports Server (NTRS)

    Castellano, Tim; DeVincenzi, Donald L. (Technical Monitor)

    2000-01-01

    The recent detection of planetary transits of the solar-like star HD 209458 at a distance of 47 parsecs suggest that transits can reveal the presence of Jupiter-size planetary companions in the solar neighborhood. Recent space-based transit searches have achieved photometric precision within an order of magnitude of that required to detect the much smaller transit signal of an earth-size planet around a solar-size star. Laboratory experiments in the presence of realistic noise sources have shown that CCDs can achieve photometric precision adequate to detect the 9.6 E-5 dimming, of the Sun due to a transit of the Earth. Space-based solar irradiance monitoring has shown that the intrinsic variability of the Sun would not preclude such a detection. Transits of the Sun by the Earth would be detectable by observers that reside within a narrow band of sky positions near the ecliptic plane, if the observers possess current Earth epoch levels of technology and astronomical expertise. A catalog of candidate target stars, their properties, and simulations of the photometric Earth transit signal detectability at each target is presented.

  10. Sensing Planet Earth - Chalmers' MOOCs on Earth observation

    NASA Astrophysics Data System (ADS)

    Hobiger, Thomas; Stöhr, Christian; Murtagh, Donal; Forkman, Peter; Galle, Bo; Mellquist, Johan; Soja, Maciej; Berg, Anders; Carvajal, Gisela; Eriksson, Leif; Haas, Rüdiger

    2016-04-01

    An increasing number of universities around the globe produce and conduct Massive Open Online Courses (MOOCs). In the beginning of 2016, Chalmers University of Technology ran two MOOCs on the topic of Earth observations on the edX platform. Both four week long courses were at introductory level and covered topics related to solid Earth, atmosphere, biosphere, hydrosphere and cryosphere. It was discussed how one can measure and trace global change and use remote sensing tools for disaster monitoring. Research has attempted to assess the learners' motivations to participate in MOOCs, but there is a need for further case studies about motivations, opportunities and challenges for teachers engaging in MOOC development. In our presentation, we are going to report about the experiences gained from both the MOOC production and the actual course run from the instructors' perspective. After brief introduction to MOOCs in general and at Chalmers in particular, we share experiences and challenges of developing lecture and assessment material, the video production and coordination efforts between and within different actors involved in the production process. Further, we reflect upon the actual run of the course including course statistics and feedback from the learners. We discuss issues such as learner activation and engagement with the material, teacher-learner and student-student interaction as well as the scalability of different learning activities. Finally, we will present our lessons-learned and conclusions on the applicability of MOOCs in the field of Earth science teaching.

  11. Earth as Seen from Mars

    NASA Technical Reports Server (NTRS)

    2005-01-01

    On its 449th martian day, or sol (April 29, 2005), NASA's Mars rover Opportunity woke up approximately an hour after sunset and took this picture of the fading twilight as the stars began to come out. Set against the fading red glow of the sky, the pale dot near the center of the picture is not a star, but a planet -- Earth.

    Earth appears elongated because it moved slightly during the 15-second exposures. The faintly blue light from the Earth combines with the reddish sky glow to give the pale white appearance.

    The images were taken with Opportunity's panoramic camera, using 440-nanometer, 530-nanometer, and 750-nanometer color filters. In processing on the ground, the images were shifted slightly to compensate for Earth's motion between one image and the next.

  12. Dark Matter Hairs Around Earth

    NASA Image and Video Library

    2015-11-23

    This illustration shows Earth surrounded by filaments of dark matter called "hairs," which are proposed in a study in the Astrophysical Journal by Gary Prézeau of NASA's Jet Propulsion Laboratory, Pasadena, California. A hair is created when a stream of dark matter particles goes through the planet. According to simulations, the hair is densest at a point called the "root." When particles of a dark matter stream pass through the core of Earth, they form a hair whose root has a particle density about a billion times greater than average. The hairs in this illustration are not to scale. Simulations show that the roots of such hairs can be 600,000 miles (1 million kilometers) from Earth, while Earth's radius is only about 4,000 miles (6,400 kilometers). http://photojournal.jpl.nasa.gov/catalog/PIA20176

  13. NASA's Current Earth Science Program

    NASA Technical Reports Server (NTRS)

    Charles, Leslie Bermann

    1998-01-01

    NASA's Earth science program is a scientific endeavor whose goal is to provide long-term understanding of the Earth as an integrated system of land, water, air and life. A highly developed scientific knowledge of the Earth system is necessary to understand how the environment affects humanity, and how humanity may be affecting the environment. The remote sensing technologies used to gather the global environmental data used in such research also have numerous practical applications. Current applications of remote sensing data demonstrate their practical benefits in areas such as the monitoring of crop conditions and yields, natural disasters and forest fires; hazardous waste clean up; and tracking of vector-borne diseases. The long-term availability of environmental data is essential for the continuity of important research and applications efforts. NASA's Earth observation program has undergone many changes in the recent past.

  14. Physical conditions on the early Earth.

    PubMed

    Lunine, Jonathan I

    2006-10-29

    The formation of the Earth as a planet was a large stochastic process in which the rapid assembly of asteroidal-to-Mars-sized bodies was followed by a more extended period of growth through collisions of these objects, facilitated by the gravitational perturbations associated with Jupiter. The Earth's inventory of water and organic molecules may have come from diverse sources, not more than 10% roughly from comets, the rest from asteroidal precursors to chondritic bodies and possibly objects near Earth's orbit for which no representative class of meteorites exists today in laboratory collections. The final assembly of the Earth included a catastrophic impact with a Mars-sized body, ejecting mantle and crustal material to form the Moon, and also devolatilizing part of the Earth. A magma ocean and steam atmosphere (possibly with silica vapour) existed briefly in this period, but terrestrial surface waters were below the critical point within 100 million years after Earth's formation, and liquid water existed continuously on the surface within a few hundred million years. Organic material delivered by comets and asteroids would have survived, in part, this violent early period, but frequent impacts of remaining debris probably prevented the continuous habitability of the Earth for one to several hundred million years. Planetary analogues to or records of this early time when life began include Io (heat flow), Titan (organic chemistry) and Venus (remnant early granites).

  15. Earth-class Planets Line Up

    NASA Image and Video Library

    2011-12-20

    This chart compares the first Earth-size planets found around a sun-like star to planets in our own solar system, Earth and Venus. NASA Kepler mission discovered the newfound planets, called Kepler-20e and Kepler-20f.

  16. South Polar Projection of Earth

    NASA Image and Video Library

    1997-09-10

    This view of the Earth shows a wonderfully unique but physically impossible view of the southern hemisphere and Antarctica. While a spacecraft could find itself directly over the Earth pole, roughly half of the image should be in darkness!

  17. Determining Possible Building Blocks of the Earth

    NASA Technical Reports Server (NTRS)

    Burbine, T. H.; O'Brien, K. M.

    2003-01-01

    Introduction: One of the fundamental questions concerning the formation of the Earth is what is it made out of. The Earth appears to have condensed out of material from the solar nebula. We sample this "primitive" material in the form of chondritic meteorites. One of the most important constraints on possible building blocks for the Earth is the Earth#s oxygen iso-topic composition. Rocks from the Earth and Moon plot along a line (the terrestrial fractionation line) in diagrams of delta(sup 17)O (% relative to Standard Mean Ocean Water or SMOW) versus delta(sup 18)O (% relative to SMOW). Chondritic meteorites fall above and below this line. Distances from this line are given as Delta(sup 17)O (%) (= delta(sup 17)O - 0.52 x delta(sup 18)O).

  18. Cosmic Influence on the Sun-Earth Environment

    PubMed Central

    Mukherjee, Saumitra

    2008-01-01

    SOHO satellite data reveals geophysical changes before sudden changes in the Earth's Sun-Earth environment. The influence of extragalactic changes on the Sun as well as the Sun-Earth environment seems to be both periodic and episodic. The periodic changes in terms of solar maxima and minima occur every 11 years, whereas the episodic changes can happen at any time. Episodic changes can be monitored by cosmic ray detectors as a sudden increase or decrease of activity. During these solar and cosmic anomaly periods the environment of the Earth is affected. The Star-Sun-Earth connection has the potential to influence the thermosphere, atmosphere, ionosphere and lithosphere. Initial correlation of the cosmic and Sun-Earth connection has shown the possibility of predicting earthquakes, sudden changes in atmospheric temperatures and erratic rainfall/snowfall patterns. PMID:27873955

  19. Mars at 43 Million Miles From Earth

    NASA Image and Video Library

    2001-06-26

    NASA Earth-orbiting Hubble Space Telescope took the picture on June 26, 2001 when Mars was approximately 43 million miles 68 million km from Earth -- the closest Mars has ever been to Earth since 1988.

  20. Earth Science

    NASA Image and Video Library

    1990-10-24

    Solar Vector Magnetograph is used to predict solar flares, and other activities associated with sun spots. This research provides new understanding about weather on the Earth, and solar-related conditions in orbit.

  1. Crescent-shaped Earth and Moon

    NASA Image and Video Library

    1999-05-15

    This picture of a crescent-shaped Earth and Moon -- the first of its kind ever taken by a spacecraft -- was recorded Sept. 18, 1977, by NASA Voyager 1 when it was 7.25 million miles 11.66 million kilometers from Earth.

  2. Immersive Earth: Teaching Earth and Space with inexpensive immersive technology

    NASA Astrophysics Data System (ADS)

    Reiff, P. H.; Sumners, C.; Law, C. C.; Handron, K.

    2003-12-01

    In 1995 we pioneered "Space Update", the Digital Library for the rest of us", software that was so simple that a child could use it without a keyboard and yet would allow one-click updating of the daily earth and space science images without the dangers of having an open web browser on display. Thanks to NASA support, it allowed museums and schools to have a powerful exhibit for a tiny price. Over 40,000 disks in our series have been distributed so far to educators and the public. In 2003, with our partners we are again revolutionizing educational technology with a low-cost hardware and software solution to creating and displaying immersive content. Recently selected for funding as part of the REASoN competition, Immersive Earth is a partnership of scientists, museums, educators, and content providers. The hardware consists of a modest projector with a special fisheye lens to be used in an inflatable dome which many schools already have. This, coupled with a modest personal computer, can now easily project images and movies of earth and space, allows training students in 3-D content at a tiny fraction of the cost of a cave or fullscale dome theater. Another low-cost solution is the "Imove" system, where spherical movies can play on a personal computer, with the user changing the viewing direction with a joystick. We were the first to create immersive earth science shows, remain the leader in creating educational content that people want to see. We encourage people with "allsky" images or movies to bring it and see what it looks like inside a dome! Your content could be in our next show!

  3. Earth Global Reference Atmospheric Model 2007 (Earth-GRAM07) Applications for the NASA Constellation Program

    NASA Technical Reports Server (NTRS)

    Leslie, Fred W.; Justus, C. G.

    2008-01-01

    Engineering models of the atmosphere are used extensively by the aerospace community for design issues related to vehicle ascent and descent. The Earth Global Reference Atmosphere Model version 2007 (Earth-GRAM07) is the latest in this series and includes a number of new features. Like previous versions, Earth-GRAM07 provides both mean values and perturbations for density, temperature, pressure, and winds, as well as monthly- and geographically-varying trace constituent concentrations. From 0 km to 27 km, thermodynamics and winds are based on the National Oceanic and Atmospheric Administration Global Upper Air Climatic Atlas (GUACA) climatology. For altitudes between 20 km and 120 km, the model uses data from the Middle Atmosphere Program (MAP). Above 120 km, EarthGRAM07 now provides users with a choice of three thermosphere models: the Marshall Engineering Thermosphere (MET-2007) model; the Jacchia-Bowman 2006 thermosphere model (JB2006); and the Naval Research Labs Mass Spectrometer, Incoherent Scatter Radar Extended Model (NRL MSIS E-OO) with the associated Harmonic Wind Model (HWM-93). In place of these datasets, Earth-GRAM07 has the option of using the new 2006 revised Range Reference Atmosphere (RRA) data, the earlier (1983) RRA data, or the user may also provide their own data as an auxiliary profile. Refinements of the perturbation model are also discussed which include wind shears more similar to those observed at the Kennedy Space Center than the previous version Earth-GRAM99.

  4. Earth Observation

    NASA Image and Video Library

    2011-08-02

    ISS028-E-020276 (2 Aug. 2011) --- This photograph of polar mesospheric clouds was acquired at an altitude of just over 202 nautical miles (about 322 kilometers) in the evening hours (03:19:54 Greenwich Mean Time) on Aug. 2, 2011, as the International Space Station was passing over the English Channel. The nadir coordinates of the station were 49.1 degrees north latitude and 5.5 degrees west longitude. Polar mesospheric clouds (also known as noctilucent, or ?night-shining? clouds) are transient, upper atmospheric phenomena that are usually observed in the summer months at high latitudes (greater than 50 degrees) of both the Northern and Southern Hemispheres. They appear bright and cloudlike while in deep twilight. They are illuminated by sunlight when the lower layers of the atmosphere are in the darkness of Earth?s shadow. The horizon of Earth appears at the bottom of the image, with some layers of the lower atmosphere already illuminated by the rising sun. The higher, bluish-colored clouds look much like wispy cirrus clouds, which can be found as high as 60,000 feet (18 kilometers) in the atmosphere. However noctilucent clouds, as seen here, are observed in the mesosphere at altitudes of 250,000 to 280,000 feet (about 76 to 85 kilometers). Astronaut observations of polar mesospheric clouds over northern Europe in the summer are not uncommon.

  5. Cloudy Earth

    NASA Image and Video Library

    2015-05-08

    Decades of satellite observations and astronaut photographs show that clouds dominate space-based views of Earth. One study based on nearly a decade of satellite data estimated that about 67 percent of Earth’s surface is typically covered by clouds. This is especially the case over the oceans, where other research shows less than 10 percent of the sky is completely clear of clouds at any one time. Over land, 30 percent of skies are completely cloud free. Earth’s cloudy nature is unmistakable in this global cloud fraction map, based on data collected by the Moderate Resolution Imaging Spectroradiometer (MODIS) on the Aqua satellite. While MODIS collects enough data to make a new global map of cloudiness every day, this version of the map shows an average of all of the satellite’s cloud observations between July 2002 and April 2015. Colors range from dark blue (no clouds) to light blue (some clouds) to white (frequent clouds). Read more here: 1.usa.gov/1P6lbMU Credit: NASA Earth Observatory NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

  6. Accumulation of rare earth elements by siderophore-forming Arthrobacter luteolus isolated from rare earth environment of Chavara, India.

    PubMed

    Emmanuel, E S Challaraj; Ananthi, T; Anandkumar, B; Maruthamuthu, S

    2012-03-01

    In this study, Arthrobacter luteolus, isolated from rare earth environment of Chavara (Quilon district, Kerala, India), were found to produce catechol-type siderophores. The bacterial strain accumulated rare earth elements such as samarium and scandium. The siderophores may play a role in the accumulation of rare earth elements. Catecholate siderophore and low-molecular-weight organic acids were found to be present in experiments with Arthrobacter luteolus. The influence of siderophore on the accumulation of rare earth elements by bacteria has been extensively discussed.

  7. The Sun and Earth

    NASA Technical Reports Server (NTRS)

    Gopalswamy, Natchimuthuk

    2012-01-01

    Thus the Sun forms the basis for life on Earth via the black body radiation it emits. The Sun also emits mass in the form of the solar wind and the coronal mass ejections (CMEs). Mass emission also occurs in the form of solar energetic particles (SEPs), which happens during CMEs and solar flares. Both the mass and electromagnetic energy output of the Sun vary over a wide range of time scales, thus introducing disturbances on the space environment that extends from the Sun through the entire heliosphere including the magnetospheres and ionospheres of planets and moons of the solar system. Although our habitat is located in the neutral atmosphere of Earth, we are intimately connected to the non-neutral space environment starting from the ionosphere to the magnetosphere and to the vast interplanetary space. The variability of the solar mass emissions results in the interaction between the solar wind plasma and the magnetospheric plasma leading to huge disturbances in the geospace. The Sun ionizes our atmosphere and creates the ionosphere. The ionosphere can be severely disturbed by the transient energy input from solar flares and the solar wind during geomagnetic storms. The complex interplay between Earth's magnetic field and the solar magnetic field carried by the solar wind presents varying conditions that are both beneficial and hazardous to life on earth. This seminar presents some of the key aspects of this Sun-Earth connection that we have learned since the birth of space science as a scientific discipline some half a century ago.

  8. Skylab explores the Earth

    NASA Technical Reports Server (NTRS)

    1977-01-01

    Data from visual observations are integrated with results of analyses of approxmately 600 of the nearly 2000 photographs taken of Earth during the 84-day Skylab 4 mission to provide additional information on (1) Earth features and processes; (2) operational procedures and constraints in observing and photographing the planet; and (3) the use of man in real-time analysis of oceanic and atmospheric phenomena.

  9. Propagation Velocity of Solid Earth Tides

    NASA Astrophysics Data System (ADS)

    Pathak, S.

    2017-12-01

    One of the significant considerations in most of the geodetic investigations is to take into account the outcome of Solid Earth tides on the location and its consequent impact on the time series of coordinates. In this research work, the propagation velocity resulting from the Solid Earth tides between the Indian stations is computed. Mean daily coordinates for the stations have been computed by applying static precise point positioning technique for a day. The computed coordinates are used as an input for computing the tidal displacements at the stations by Gravity method along three directions at 1-minute interval for 24 hours. Further the baseline distances are computed between four Indian stations. Computation of the propagation velocity for Solid Earth tides can be done by the virtue of study of the concurrent effect of it in-between the stations of identified baseline distance along with the time consumed by the tides for reaching from one station to another. The propagation velocity helps in distinguishing the impact at any station if the consequence at a known station for a specific time-period is known. Thus, with the knowledge of propagation velocity, the spatial and temporal effects of solid earth tides can be estimated with respect to a known station. As theoretically explained, the tides generated are due to the position of celestial bodies rotating about Earth. So the need of study is to observe the correlation of propagation velocity with the rotation speed of the Earth. The propagation velocity of Solid Earth tides comes out to be in the range of 440-470 m/s. This velocity comes out to be in a good agreement with the Earth's rotation speed.

  10. Evolution of Earth&'s Atmosphere and Climate

    NASA Astrophysics Data System (ADS)

    Kasting, J. F.

    2004-12-01

    Earth's climate prior to 2.5 Ga seems to have been, if anything, warmer than today (1,2), despite the faintness of the young Sun (3). The idea that the young Sun was 25-30 percent less bright has been bolstered by data on mass loss from young, solar-type stars (4). Sagan and Mullen (1) suggested many years ago that the warming required to offset low solar luminosity was provided by high concentrations of reduced greenhouse gases. Ammonia has since been shown to be photochemically unstable in low-O2 atmospheres (5), but methane is a viable candidate. Methane photolyzes only at wavelengths shorter than 145 nm, so it is long-lived in the absence of O2 and O3. Furthermore, it is produced by anaerobic bacteria (methanogens) that are thought to have evolved early in Earth history (6). A biological methane flux comparable to today's flux, ~500 Tg CH4/yr, could have been generated by methanogens living in an anaerobic early ocean and sediments (7). This flux should have increased once oxygenic photosynthesis evolved because of increased production and recycling of organic matter (8). An Archean methane flux equal to today's flux could have generated atmospheric CH4 concentrations in excess of 1000 ppmv (9). This, in turn, could have provided 30 degrees or more of greenhouse warming (10) enough to have kept the early Earth warm even if atmospheric CO2 was no higher than today. All of this does not imply that CO2 concentrations must have been low throughout the Archean. Indeed, siderite-coated stream pebbles imply that pCO2 was greater than 2.5,e10-3 bar, or ~7 times present, at 3.2 Ga (11). Atmospheric CO2 could have been much higher than this if the continents had formed slowly (12) and/or if subduction of carbonates was inhibited (13). The rise in O2 at ~2.3 Ga (14,15) brought an end to the methane greenhouse and may have triggered the Huronian glaciation (10). Although methane concentrations declined with the rise of O2, they may still have remained much higher than

  11. Earth Observation

    NASA Image and Video Library

    2013-08-03

    Earth observation taken during day pass by an Expedition 36 crew member on board the International Space Station (ISS). Per Twitter message: Perhaps a dandelion losing its seeds in the wind? Love clouds!

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

    NASA Astrophysics Data System (ADS)

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

    2018-05-01

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

  13. Discovering and measuring a layered Earth: A foundational laboratory for developing students' understanding of Earth's interior structure

    NASA Astrophysics Data System (ADS)

    Hubenthal, M.; Braile, L. W.; Olds, S. E.; Taber, J.

    2010-12-01

    Geophysics research is continuously revealing new insights about Earth’s interior structure. Before students can grasp theses new complexities, they first must internalize the 1st order layered structure of Earth and comprehend how seismology contributes to the development of such models. Earth structure is of course covered in most introductory geoscience courses, though all too often instruction of this content is limited to didactic methods that make little effort to inspire or engage the minds of students. In the process, students are expected to blindly accept our understanding of the unseen and abstract. Thus, it is not surprising then that many students can draw a layered Earth diagram, yet not know that knowledge of Earth’s interior is based on information from earthquakes. Cognitive learning theory would suggest that what has been missing from instruction of Earth structure is a feasible method to present students with seismic evidence in a manner that allows students to become minds-on with the content; discovering or dispelling the presence of a layered Earth for themselves. Recent advances in serving seismic data to a non-seismologist audience have made the development of such laboratory investigations possible. In this exercise students use an inquiry approach to examine seismic evidence and determine that the Earth cannot have a homogeneous composition. Further they use the data to estimate the dimensions of Earth’s outer core. To reach these conclusions, students are divided into two teams, theoreticians and seismologists, to test the simplest hypothesis for Earth's internal structure; a homogeneous Earth. The theoreticians create a scale model of a homogeneous Earth and predict when seismic waves should arrive at various points on the model. Simultaneously, seismologists interpret a seismic record section from a recent earthquake noting when seismic waves arrive at various points around Earth. The two groups of students then compare the

  14. Looking at Earth from Space: Teacher's Guide with Activities for Earth and Space Science.

    ERIC Educational Resources Information Center

    National Aeronautics and Space Administration, Washington, DC.

    The Maryland Pilot Earth Science and Technology Education Network (MAPS-NET) project was sponsored by the National Aeronautics and Space Administration (NASA) to enrich teacher preparation and classroom learning in the area of Earth system science. This publication includes a teacher's guide that replicates material taught during a graduate-level…

  15. Human Exploration of Earth's Neighborhood and Mars

    NASA Technical Reports Server (NTRS)

    Condon, Gerald

    2003-01-01

    The presentation examines Mars landing scenarios, Earth to Moon transfers comparing direct vs. via libration points. Lunar transfer/orbit diagrams, comparison of opposition class and conjunction class missions, and artificial gravity for human exploration missions. Slides related to Mars landing scenarios include: mission scenario; direct entry landing locations; 2005 opportunity - Type 1; Earth-mars superior conjunction; Lander latitude accessibility; Low thrust - Earth return phase; SEP Earth return sequence; Missions - 200, 2007, 2009; and Mission map. Slides related to Earth to Moon transfers (direct vs. via libration points (L1, L2) include libration point missions, expeditionary vs. evolutionary, Earth-Moon L1 - gateway for lunar surface operations, and Lunar mission libration point vs. lunar orbit rendezvous (LOR). Slides related to lunar transfer/orbit diagrams include: trans-lunar trajectory from ISS parking orbit, trans-Earth trajectories, parking orbit considerations, and landing latitude restrictions. Slides related to comparison of opposition class (short-stay) and conjunction class (long-stay) missions for human exploration of Mars include: Mars mission planning, Earth-Mars orbital characteristics, delta-V variations, and Mars mission duration comparison. Slides related to artificial gravity for human exploration missions include: current configuration, NEP thruster location trades, minor axis rotation, and example load paths.

  16. Earth Surface Processes, Landforms and Sediment Deposits

    NASA Astrophysics Data System (ADS)

    Bridge, John; Demicco, Robert

    Earth surface processes, landforms and sediment deposits are intimately related - involving erosion of rocks, generation of sediment, and transport and deposition of sediment through various Earth surface environments. These processes, and the landforms and deposits that they generate, have a fundamental bearing on engineering, environmental and public safety issues; on recovery of economic resources; and on our understanding of Earth history. This unique textbook brings together the traditional disciplines of sedimentology and geomorphology to explain Earth surface processes, landforms and sediment deposits in a comprehensive and integrated way. It is the ideal resource for a two-semester course in sedimentology, stratigraphy, geomorphology, and Earth surface processes from the intermediate undergraduate to beginning graduate level. The book is also accompanied by a website hosting illustrations and material on field and laboratory methods for measuring, describing and analyzing Earth surface processes, landforms and sediments.

  17. Lait humain provenant d’une banque de dons ou acheté en ligne?

    PubMed Central

    St-Onge, Maude; Chaudhry, Shahnaz; Koren, Gideon

    2015-01-01

    Résumé Question Une de mes patientes m’a demandé si elle pourrait se procurer du lait humain par Internet pour allaiter son nourrisson s’il le fallait. L’usage de lait humain provenant d’une banque de dons est-il plus sécuritaire que son achat en ligne? Réponse L’Organisation mondiale de la Santé et l’American Academy of Pediatrics recommandent d’utiliser des dons de lait humain comme choix à privilégier lorsque le lait maternel n’est pas disponible. Cependant, la Société canadienne de pédiatrie n’approuve pas le partage de lait humain non traité. Le lait humain entreposé dans les banques de lait diffère de celui qu’on peut se procurer par Internet en raison du processus rigoureux de sélection des donneuses, des fréquentes inspections de la qualité, des procédés de transport règlementés et du processus de pasteurisation conforme aux directives établies par l’Agence canadienne d’inspection des aliments. La plupart des échantillons achetés en ligne contiennent des bactéries à gram négatif ou comptent au total plus de 104 unités formant colonies de bactéries aérobiques par millilitre; ils renferment aussi en moyenne au décompte total plus de bactéries aérobiques, de bactéries à gram négatif, de coliformes et de Staphylococcus spp que les échantillons des banques de lait. La croissance de la plupart des espèces de bactéries est associée au nombre de jours en transit, ce qui porte à croire que les conditions de collecte, d’entreposage et de transport sont médiocres pour le lait acheté en ligne.

  18. Spectra of Th/Ar and U/Ne hollow cathode lamps for spectrograph calibration

    NASA Astrophysics Data System (ADS)

    Nave, Gillian; Shlosberg, Ariel; Kerber, Florian; Den Hartog, Elizabeth; Neureiter, Bianca

    2018-01-01

    Low-current Th/Ar hollow cathode lamps have long been used for calibration of astronomical spectrographs on ground-based telescopes. Thorium is an attractive element for calibration as it has a single isotope, has narrow spectral lines, and has a dense spectrum covering the whole of the visible region. However, the high density of the spectrum that makes it attractive for calibrating high-resolution spectrographs is a detriment for lower resolution spectrographs and this is not obvious by examination of existing linelists. In addition, recent changes in regulations regarding the handling of thorium have led to a degradation in the quality of Th/Ar calibration lamps, with contamination by molecular ThO lines that are strong enough to obscure the calibration lines of interest.We are pursuing two approaches to these problems. First, we have expanded and improved the NIST Standard Reference Database 161, "Spectrum of Th-Ar Hollow Cathode Lamps" to cover the region 272 nm to 5500 nm. Spectra of hollow cathode lamps at up to 3 different currents can now be displayed simultaneously. Interactive zooming and the ability to convolve any of the spectra with a Gaussian or uploaded instrument profile enable the user to see immediately what the spectrum would look like at the particular resolution of their spectrograph. Second, we have measured the spectrum of a recent, contaminated Th/Ar hollow cathode lamp using a high-resolution Echelle spectrograph (Madison Wisconsin) at a resolving power (R~ 250,000). This significantly exceeds the resolving power of most astronomical spectrographs and resolves many of the molecular lines of ThO. With these spectra we are measuring and calibrating the positions of these molecular lines in order to make them suitable for spectrograph calibration.In the near infrared region, U/Ne hollow cathode lamps give a higher density of calibration lines than Th/Ar lamps and will be implemented on the upgraded CRIRES+ spectrograph on ESO’s Very Large

  19. EarthCube's Assessment Framework: Ensuring Return on Investment

    NASA Astrophysics Data System (ADS)

    Lehnert, K.

    2016-12-01

    EarthCube is a community-governed, NSF-funded initiative to transform geoscience research by developing cyberinfrastructure that improves access, sharing, visualization, and analysis of all forms of geosciences data and related resources. EarthCube's goal is to enable geoscientists to tackle the challenges of understanding and predicting a complex and evolving solid Earth, hydrosphere, atmosphere, and space environment systems. EarthCube's infrastructure needs capabilities around data, software, and systems. It is essential for EarthCube to determine the value of new capabilities for the community and the progress of the overall effort to demonstrate its value to the science community and Return on Investment for the NSF. EarthCube is therefore developing an assessment framework for research proposals, projects funded by EarthCube, and the overall EarthCube program. As a first step, a software assessment framework has been developed that addresses the EarthCube Strategic Vision by promoting best practices in software development, complete and useful documentation, interoperability, standards adherence, open science, and education and training opportunities for research developers.

  20. Near-Earth Asteroid Scout

    NASA Technical Reports Server (NTRS)

    Walden, Amy; Clardy, Dennon; Johnson, Les

    2015-01-01

    Near-Earth asteroids (NEAs) are easily accessible objects in Earth's vicinity. As NASA continues to refine its plans to possibly explore NEAs with humans, initial reconnaissance with comparatively inexpensive robotic precursors is necessary. Obtaining and analyzing relevant data about these bodies via robotic precursors before committing a crew to visit an NEA will significantly minimize crew and mission risk, as well as maximize exploration return potential. The NASA Marshall Space Flight Center (MSFC) and NASA Jet Propulsion Laboratory are jointly developing the Near-Earth Asteroid Scout (NEAS) utilizing a low-cost CubeSat platform in response to the current needs for affordable missions with exploration science value. The mission is enabled by the use of an 85-sq m solar sail being developed by MSFC (figs. 1 and 2).