53 research outputs found
The Cambrian of the Iberian Peninsula : an overview
This work is a brief overview of the Cambrian in the Iberian Peninsula, along with an updated review of lithostratigraphic and biostratigraphic data. A Cambrian correlation chart between the different stratigraphical units that have been established in the Iberian Peninsula is given. We also reappraise the Lower and Middle Cambrian regional stages in the light of new palaeontological data, and the different biozonations proposed with several palaeontological groups
Las células troncales pluripotenciales en la terapia celular
Las células con pluripotencialidad inducida (iPS) son
un nuevo tipo de célula troncal derivada de células somáticas
humanas, mediante reprogramación con factores de
transcripción. Estas células iPS tienen características de
las células troncales embrionarias, como la capacidad de
convertirse en todos los tipos de células diferenciadas
del organismo. A corto plazo, las células de pacientes
reprogramadas están siendo útiles para crear modelos
celulares de enfermedades, en las que estudiar los procesos
patológicos y probar fármacos. A pesar de algunas
críticas, se ha ido acumulando evidencia en los trabajos
preclínicos, sobre la efectividad de la terapia celular con
los clones de iPS apropiadamente seleccionados. La generación
de células iPS ha propiciado el desarrollo de
otras técnicas,como por ejemplo, la transdiferenciación
por la que se convierte directamente in vivo fibroblastos
cardiacos en miocitos. Este tipo celular pluripotencial es
de un gran valor en la investigación biomedicina y abre
nuevas posibilidades a la terapia celular.Induced pluripotent stem (iPS) cells are a novel
stem cell population derived from human somatic cells
through reprogramming using a set of transcription factors.
These iPS cells were shown to share the characteristics
of embryonic stem cells, including the ability to
give rise to differentiated cells of every tissue type of
the body. In the shorter term, iPS cells will be useful for
creating patient-identical disease model cells in which
the pathological process can be studied and drugs
can be tested. Despite critical attitudes, accumulating
preclinical evidence supports the effectiveness of iPSCbased
cell therapy on the selection of appropriate iPSC
clones. The production of iPS cells has also spurred the
development of other techniques, for example, transdifferentiation
by researchers can now convert heart
fibroblasts directly in vivo into myocytes by similar
methods. This pluripotent cells is indeed of great value
in medical research and it is opening new possibilities
in cell therapy
A new occurence of the genus Tonkinella in northern Spain and the Middle Cambrian intercontinental correlation
The genus Tonkinella is a typical polimeroid trilobite in lower Middle Cambrian rocks from Vietnam, Canada, U.S.A., India, Korea, Siberia, China and Argentina. It has recently been found in the Mediterranean region (Iberian Chain, northeastern Spain). In this paper we refer the finding of Tonkinella aff. breviceps in the Leonian (lower Middle Cambrian) of the Cantabrian Mountains (northern Spain), analysing its stratigraphical position, fossil assemblages, biochronology and utility for intercontinental correlation. The presence of this taxon allows us to make a more accurate correlation between the Middle Cambrian biochronological scales of Laurentia, the Mediterranean area and China
Estratigrafía y petrología del subsuelo recuaternario del sector sw de la depresión de Barcelona (cadenas costeras catalanas, ne de Iberia)
[email protected] numerosas obras de Ingeniería Civil que se han realizado en los últimos años en la
depresión de Barcelona (ampliación del aeropuerto, ampliación del metro y AVE fundamentalmente)
han permitido recabar mucha información sobre el subsuelo de esta área. En este trabajo se caracterizan
las distintas unidades de subsuelo precuaternarias que aparecen en los numerosos sondeos realizados
recientemente en la zona SW de la depresión de Barcelona. Se ha identificado un sustrato triásico
formado por areniscas del Buntsandstein y dos unidades de edad Miocena, una basal de carácter
continental y otra superior depositada en un ambiente marino. Todas estas unidades fueron fracturadas
debido a una tectónica extensiva y, posteriormente, fueron fosilizadas en primer lugar por los sedimentos
del Plioceno, que recubren la superficie de erosión messiniense, y finalmente, por el Cuaternario. El
análisis de las distintas unidades permite obtener datos sobre la evolución paleogeográfica y tectónica
de la depresión de Barcelona durante el Mioceno y el Plioceno.Current building of civil Engineering infrastructures in the Barcelona plain and Llobregat
delta (mainly metro and airport extension and high speed train) is providing new geological subsurface
data to build better geologic models and understand the basin evolution. This work focuses on the
pre-Quaternary units observed in cores. Based on petrographic analyses combined when it was possible
with paleontological studies, we identified the lower Triassic Buntsandstein sandstone facies and
Miocene continental and marine facies which appear compartmentalized due to extensive deformation.
After this extensive episode, Pliocene and Quaternary sediments, which were deposited after the
development of successive erosive surfaces, overlay the Triassic and Miocene units. The identification
of these units enabled one to improve the interpretation of the tectonic and paleogeographic evolution
of the Barcelona plain
Volcanic sequence in Late Triassic – Jurassicsiliciclastic and evaporitic rocks from Galeana, NE Mexico
In northeastern Mexico, volcanic rocks interbedded with Late Triassic–Jurassic siliciclastic and evaporitic strata have been linked to magmatic arcs developed in the Pangea western margin during its initial phase of fragmentation. This work provides new petrographic and geochemical data for volcanism included in the El Alamar and Minas Viejas formations outcropping in the Galeana region. Andesitic dykes and sills (n= 10) in the El Alamar redbeds show SiO2= 47.5–59.1% and MgO= 1.2–4.2%, as well as a geochemical affinity to island arc magmas. This work represents the first report of this tectonic setting in the region. Geological and petrographic evidence suggest that this arc system likely developed after ~220 and before ~193Ma. Trachy-andesitic and rhyodacitic domes (n= 20) associated with the Minas Viejas gypsum-carbonates sequence show SiO2= 61.8–82.7% and MgO= 0.1–4.0% with a tectonic affinity to continental arc. A rhyodacite sample from this region has been dated by U-Pb in zircon, yielding an age of 149.4 ± 1.2Ma (n= 21), being the youngest age related to this arc. Finally, we propose a threestep model to explain the tectonic evolution from Late Triassic island arc to Jurassic continental arc system in the northeastern Mexico
Identification of non-small cell lung cancer biomarkers using mass spectrometry
Comunicaciones a congreso
V-shaped pyranylidene/triphenylamine-based chromophores with enhanced photophysical, electrochemical and nonlinear optical properties
We report the synthesis and comprehensive study of two chromophores based on 4H-pyranylidene moiety as a part of the p-conjugated spacer. Triphenylamine (TPA) acts as donor and tricarbonitrile-based electron-accepting groups complete these V-shaped D-A-D architectures (A, acceptor; D, donor). Their electrochemical, photophysical and nonlinear optical properties are analyzed in detail by using a joint experimental and theoretical approach. The two chromophores exhibit near-infrared fluorescence, large Stokes shift, enhanced emission in tetrahydrofuran/water mixtures and good photostability. Additionally, the dimerization of triphenylamine groups to tetraphenylbenzidine (TPB) takes place upon electrochemical and chemical oxidation showing their peculiar electrochemical behavior and film formation capabilities. Interestingly, high molecular first hyperpolarizabilities and two-photon absorption cross-sections were found, highlighting their potential applications in electro-optical devices. Overall, our work demonstrates that these near-infrared (NIR) fluorescent chromophores are versatile materials with a myriad of applications ranging from optoelectronics to biological applications. © 2021 The Royal Society of Chemistry
La secuencia litoestratigráfica del Neoproterozoico-Cámbrico Inferior
Depto. de Mineralogía y PetrologíaFac. de Ciencias GeológicasTRUEpu
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