Relaxivity of Gd-based contrast agents on X nuclei with long intrinsic relaxation times in aqueous solutions.

The relaxivity of commercially available gadolinium (Gd)-based contrast agents was studied for X-nuclei resonances with long intrinsic relaxation times ranging from 6 s to several hundred seconds. Omniscan in pure 13C formic acid had a relaxivity of 2.9 mM(-1) s(-1), whereas its relaxivity on glutamate C1 and C5 in aqueous solution was approximately 0.5 mM(-1) s(-1). Both relaxivities allow the preparation of solutions with a predetermined short T1 and suggest that in vitro substantial sensitivity gains in their measurement can be achieved. 6Li has a long intrinsic relaxation time, on the order of several minutes, which was strongly affected by the contrast agents. Relaxivity ranged from approximately 0.1 mM(-1) s(-1) for Omniscan to 0.3 for Magnevist, whereas the relaxivity of Gd-DOTP was at 11 mM(-1) s(-1), which is two orders of magnitude higher. Overall, these experiments suggest that the presence of 0.1- to 10-microM contrast agents should be detectable, provided sufficient sensitivity is available, such as that afforded by hyperpolarization, recently introduced to in vivo imaging.

An AdS/QCD model from tachyon condensation: II

A simple holographic model is presented and analyzed that describes chiral symmetry breaking and the physics of the meson sector in QCD. This is a bottom-up model that incorporates string theory ingredients like tachyon condensation which is expected to be the main manifestation of chiral symmetry breaking in the holographic context. As a model for glue the Kuperstein-Sonnenschein background is used. The structure of the flavor vacuum is analyzed in the quenched approximation. Chiral symmetry breaking is shown at zero temperature. Above the deconfinement transition chiral symmetry is restored. A complete holographic renormalization is performed and the chiral condensate is calculated for different quark masses both at zero and non-zero temperatures. The 0++, 0¿+, 1++, 1¿¿ meson trajectories are analyzed and their masses and decay constants are computed. The asymptotic trajectories are linear. The model has one phenomenological parameter beyond those of QCD that affects the 1++, 0¿+ sectors. Fitting this parameter we obtain very good agreement with data. The model improves in several ways the popular hard-wall and soft wall bottom-up models.

Polychlorinated trityl radicals for dynamic nuclear polarization: the role of chlorine nuclei

Polychlorinated trityl radicals bearing carboxylate substituents are water soluble persistent radicals that can be used for dynamic nuclear polarization. In contrast to other trityl radicals, the polarization mechanism differs from the classical solid effect. DFT calculations performed to rationalize this behaviour support the hypothesis that polarization is transferred from the unpaired electron to chlorine nuclei and from these to carbon by spin diffusion. The marked differences observed between neutral and anionic forms of the radical will be discussed.

Anàlisi comparativa d'accessibilitat i UX d'iTunes, Google Music i Amazon Cloud Player

Aquest treball final de carrera consisteix en la realització d'un estudi de la usabilitat i accessibilitat de tres gestors de medis multimèdia: iTunes, Google Music i Amazon Cloud Player. A través d'observacions contextuals, avaluacions heurístiques i tests d'usuaris he realitzat una anàlisi comparativa. Per tal d'esquematitzar tota aquesta informació he confeccionat una taula amb els punts forts i punts febles de cada aplicació per concloure amb la proposta de millores per a cada un dels gestors de medis.

Changes in D-serine levels and localization during postnatal development of the rat vestibular nuclei.

The patterns of development of the vestibular nuclei (VN) and their main connections involving glutamate neurotransmission offer a good model for studying the function of the glial-derived neuromodulator D-serine in synaptic plasticity. In this study we show that D-serine is present in the VN and we analyzed its distribution and the levels of expression of serine racemase and D-amino acid oxidase (D-AAO) at different stages of postnatal (P) development. From birth to P21, high levels of D-serine were detected in glial cells and processes in all parts of the VN. This period corresponded to high expression of serine racemase and low expression of D-AAO. On the other hand, in the mature VN D-serine displayed very low levels and was mainly localized in neuronal cell bodies and dendrites. This drop of D-serine in adult stages corresponded to an increasing expression of D-AAO at mature stages. High levels of glial D-serine during the first 3 weeks of postnatal development correspond to an intense period of plasticity and synaptogenesis and maturation of VN afferents, suggesting that D-serine could be involved in these phenomena. These results demonstrate for the first time that changes in D-serine levels and distribution occur during postnatal development in the central nervous system. The strong decrease of D-serine levels and the glial-to-neuronal switch suggests that D-serine may have distinct functional roles depending on the developmental stage of the vestibular network.

Estado del arte en soluciones de virtualización : Sistemas gestores de Cloud: OpenNebula

En el presente proyecto se ha abordado la tarea de acercar las tecnologías existentes de plataformas de gestión de infraestructuras ofrecidas en la nube (Cloud Management Platform, aka CMP) al mundo empresarial. En concreto, se ha desplegado una solución de explotación de infraestructuras privadas en la nube (IaaS) enfocada a la gestión de un datacenter virtualizado, utilizando para ello soluciones completamente basadas en software libre, en concreto, OpenNebula.

Estado del arte en soluciones de virtualización/sistemas gestores cloud : OpenStack

Los servicios cloud se utilizan cada vez más en todo tipo de entornos, y la tendencia no hará sino acentuarse en los próximos años. Amazon AWS es líder de servicios IaaS y todos pretenden imitarles con éxito. OpenStack es una de las soluciones OpenSource con más apoyo de la comunidad y de sponsors de renombre. El presente proyecto introduce la arquitectura OpenStack y desarrolla un proyecto real de explotación IaaS basado en ésta.

Sistema de community cloud aplicat a la preservació digital personal (personal archiving) PYRAMID

La preservació digital (PD) s'ha convertit en un problema persistent per a tots els que vulguin conservar la seva informació digital, garantir el seu estat i consultar aquest informació en el transcurs del temps. Fins ara només grans institucions amb coneixement expert i eines especialitzades han pogut fer front a aquest problema, però la preservació digital no pot ser abordada per una sola institució o nació. Les biblioteques, arxius i altres institucions de conservació de la memòria comparteixen aquest repte de la mateixa manera que els col•leccionistes i creadors, que ho fan a títol individual.L’objectiu del projecte és crear l'aplicació Pyramid que està concebuda com una eina de suport orientada a l'usuari domèstic (sense coneixements tècnics ni de preservació) per a la preservació a mig i llarg termini de col•leccions digitals, texts i vídeos, tal que funcioni com un antivirus (en BackGround) i preservi la informació sense requerir un cost addicional a l'ordinador i que l'usuari no noti cap molèstia a l'hora de fer les seves tasques diàries

Sentence de la prévôté de l'Hôtel du roi, et grande prévôté de France, rendue au profit de Mr de la Roche, garde de la porte de Mgr le comte d'Artois, contre les curé et marguillers de Séve (Sèvres) près Saint-Cloud...

[Acte. 1778-09-30. Paris]

Retrieving Cloud Characteristics from Ground-Based Daytime Color All-Sky Images

A discussion is presented of daytime sky imaging and techniques that may be applied to the analysis of full-color sky images to infer cloud macrophysical properties. Descriptions of two different types of skyimaging systems developed by the authors are presented, one of which has been developed into a commercially available instrument. Retrievals of fractional sky cover from automated processing methods are compared to human retrievals, both from direct observations and visual analyses of sky images. Although some uncertainty exists in fractional sky cover retrievals from sky images, this uncertainty is no greater than that attached to human observations for the commercially available sky-imager retrievals. Thus, the application of automatic digital image processing techniques on sky images is a useful method to complement, or even replace, traditional human observations of sky cover and, potentially, cloud type. Additionally, the possibilities for inferring other cloud parameters such as cloud brokenness and solar obstruction further enhance the usefulness of sky imagers

Des cheminements sur la voie royale : une analyse sociologique des parcours de vie des normaliens-ne-s de Saint-Cloud, Fontenay-aux-Roses et Lyon (1981-1987)

Cette thèse est consacrée à l'analyse des parcours de vie d'un groupe d'anciens et anciennes élèves d'un établissement scolaire d'élite français (les Ecoles normales supérieures de Fontenay-aux-roses, Saint-Cloud et Lyon - promotions 1981-1987). A partir d'une approche longitudinale, son but est de montrer comment l'articulation entre la socialisation familiale, scolaire, professionnelle et conjugale participe à l'orientation progressive des parcours de vie des normalien-ne-s. Elle vise ainsi à remettre en question l'idée, largement répandue, selon laquelle l'intégration d'un cursus scolaire aussi sélectif et prestigieux que celui des ENS garantirait à Lou.te.s les élèves les mêmes chances d'accès aux positions dominantes de l'espace social. Alliant l'analyse de trois types de données (archives, questionnaires, entretiens), cette thèse met en évidence la manière dont inégalités relatives à l'origine sociale et au sexe se recomposent, une fois les portes de l'institution franchies. Elle montre que, dans un contexte socio-historique marqué par une forte expansion scolaire, il est plus que jamais nécessaire d'opérer une articulation systématique entre l'analyse des conditions sociales de réussite scolaire et l'analyse des conditions sociales d'exploitation des titres scolaires, afin de rendre compte des processus complexes de reproduction des inégalités et d'esquisser certaines de leur conditions de dépassement. Abstract: This thesis is dedicated to the life course analysis of alumni from one of the most prestigious French Grandes écoles (the Ecoles Normales Supérieures of Fontenay-aux- roses, Saint-Cloud and Lyon - classes of 1981.-1987). Through a longitudinal perspective, it aims to analyze how family, educational, professional and conjugal socialization processes combine to shape the life course of this particular group of graduates. The main goal of this research is to question the widespread belief that the French Grandes Ecoles guarantee automatic access to the very top of the professional and social hierarchy for all of their graduates. Based on a mixed methods research design (archive data, a questionnaire survey and semi-structured interviews), this thesis shows that, according to social origin and gender, ENS graduates actually adopt a diverse range of professional careers. It show how, in a socio-historical context characterized by a general increase in educational levels, any analysis of social inequalities should combine two levels of analysis: the social conditions of access to educational credentials, on the one hand, and the labor market value of formal qualifications, on the other hand. Our results suggest that the combined analysis of these two processes provide useful insight into the increasingly complex processes of social reproduction - and suggest fruitful perspectives for reducing some sources of inequality.

Cloud Corporatiu

Detall d'una implementació d'un sistema de computació al núvol a baixa escala i a nivell corporatiu.

18/4/20, [avenue du Palais à] St Cloud, concours de patinettes à moteur, Myrtho Laverne [sur la machine] : [photographie de presse] / [Agence Rol]

Référence bibliographique : Rol, 58923