Search results for "raton"
showing 10 items of 156 documents
Precambrian basement around Wadi Halfa, Sudan: a new perspective on the evolution of the East Saharan Craton
1994
This paper provides new geochemical and isotopic data on the evolution of the western foreland to the Nubian shield of north-east Africa. There is abundant evidence for early to middle Proterozoic crust west of the River Nile, but this was severely affected by the Pan-African (~ 500-900 Ma) orogenic cycle. The results are reported of Rb-Sr whole rock and zircon evaporation geochronological studies and whole rock Sm-Nd and feldspar Pb isotopic analyses for four rock units around Wadi Halfa in northern- most Sudan. These results indicate the presence of heterogeneous pre-Pan-African crustal components, preserved in mylonitic gneisses and in conglomerates that unconformably overlie the gneisse…
Depositional ages and provenance of the Neoproterozoic Damara Supergroup (northwest Namibia): implications for the Angola-Congo and Kalahari cratons …
2017
Abstract The Damara Orogen is composed of the Damara, Kaoko and Gariep belts developed during the Neoproterozoic Pan-African Orogeny. The Damara Belt contains Neoproterozoic siliciclastic and carbonate successions of the Damara Supergroup that record rift to proto-ocean depositional phases during the Rodinia supercontinent break up. There are two conflicting interpretations of the geotectonic framework of the Damara Supergroup basin: i) as one major basin, composed of the Outjo and Khomas basins, related to rifting in the Angola-Congo-Kalahari paleocontinent or, ii) as two independent passive margin basins, one related to the Angola-Congo and the other to the Kalahari proto-cratons. Detrita…
LA-ICP-MS U–Pb dating of detrital rutile and zircon from the Reynolds Range: A window into the Palaeoproterozoic tectonosedimentary evolution of the …
2014
Abstract The Palaeoproterozoic Reynolds Range of the Arunta Region, central Australia, comprises a series of shallow marine clastic sediments (Reynolds Range Group) which overlies deeper water sequences of turbidites (Lander Rock Formation) and minor sandstones (“unnamed sandstone”). U–Pb age data collected from detrital rutile and zircon in these rocks indicates these sequences contain very similar age spectra, although with a notable and important shift to younger ages within the stratigraphically younger Reynolds Range Group. Detrital zircons from the “unnamed sandstone” directly underlying the unconformity with the Reynolds Range Group contain a major age component at ca. 1860 Ma, toget…
Papel de hemo oxigensa-1 en la artritis inducida por transferencia de suero K/BxN. Caracterización del modelo experimental
2017
La Artritis Reumatoide (AR) es una enfermedad sistémica, crónica y de carácter autoinmune que produce daño articular en los pacientes. Cursa con la degradación del hueso subcondral y del cartílago articular causando un gran dolor; además de ser una enfermedad incapacitante, puede provocar síntomas extraarticulares que afecten a otros órganos. El estudio de la patogenia y del tratamiento de la AR se desarrolla en gran medida sobre modelos animales de artritis experimental. En la actualidad existen varios modelos de artritis en ratón ampliamente utilizados como son el modelo de Artritis Inducida por Colágeno (CIA) y el modelo por transferencia de suero K/BxN. Aunque ambos son de gran utilidad…
Efectos del estrés social sobre la memoria y su modulación farmacológica en ratones
2017
Todos hemos experimentado estrés alguna vez en nuestra vida, pero ¿qué es el estrés? Es una pregunta difícil de responder debido a que hay tantas definiciones del término como personas existen. De hecho, Hans Selye, uno de los fundadores del concepto moderno de estrés, afirmaba que “todo el mundo sabe qué es estrés y, al mismo tiempo, nadie sabe qué es estrés” (Selye, 1973). Más recientemente, McEwen y Wingfield (McEwen y Wingfield, 2003) planteaban que “el problema con el término estrés es que posee demasiados significados”. En el caso de los seres humanos, en tanto que especie social, el entorno y las relaciones interpersonales pueden llegar a establecerse como una fuente inagotable de es…
Eclogites and garnet pyroxenites: Similarities and differences
2010
Eclogites and garnet pyroxenites are genetically linked to basaltic precursors. Traditionally garnet pyroxenites are linked to fractionation of basaltic Magmas Over a range of mantle pressures and more recently they have been implicated in the genesis of ocean islands. in contrast eclogites are linked to the subduction of slab basalt and gabbro precursors which may be hydrothermally altered. Recently this subduction paradigm has been questioned. We present mineralogical, trace element and O isotopic data for eclogites and garnet pyroxenites that reveal some similarities but also important chemical and isotopic differences that support a distinct provenance (i.e., age and process). Continent…
In bilico tra Greci e “Barbari”: Maratona, la statua di Nemesis a Ramnunte e la costruzione di un mito identitario
2022
Il contributo propone un'analisi del ruolo e della funzione che nel processo di costruzione dell’Altro assumono gli oggetti inanimati e i manufatti costruiti dall’uomo. La circostanza presa in esame è relativa a una notizia riportata, nel II sec. della nostra era, nel primo libro della Periegesi di Pausania. In visita nel demo attico di Ramnunte, il Periegeta mette infatti in relazione la vittoria conseguita dagli Ateniesi a Maratona contro i Persiani, nel 490 a.C., e la dedica della statua della divinità greca Nemesis nel santuario locale, scolpita con un blocco di marmo pario che i nemici avevano portato con loro, con il proposito di farne un trofeo, certi che avrebbero avuto la meglio ne…
Il danno delle cellule epiteliali bronchiali negli atleti: Una minaccia per la salute delle vie respiratorie?
Deformation Quantization by Moyal Star-Product and Stratonovich Chaos
2012
We make a deformation quantization by Moyal star-product on a space of functions endowed with the normalized Wick product and where Stratonovich chaos are well defined.
Set-valued and fuzzy stochastic differential equations driven by semimartingales
2013
Abstract In the paper we present set-valued and fuzzy stochastic integrals with respect to semimartingale integrators as well as their main properties. Then we study the existence of solutions to set-valued and fuzzy-set-valued stochastic differential equations driven by semimartingales. The stability of solutions is also established.