Aportaciones al conocimiento de la evolución paleoclimática y paleoambiental en la Península Ibérica durante los dos ultimos millones de años a partir del estudio de trasvertinos y espeleotemas

En este trabajo se contemplan los resultados principales del Proyecto" Reconstrucción Paleoclimática desde el Pleistoceno Medio a partir de análisis geocronológicos e isotópicos de travertinos españoles" (P. CEC FI2W-CT91-0075 " Paleoclimatological revision of climate evolution in the Western Mediterranean Region, Evaluation of altered scenarios) . Se seleccionaron cuatro áreas de depósitos travertínicos de carácter fluvial (Priego, Río Blanco), lacustre (Río Blanco, Banyoles) y aluvial (Tolox) así como una zona con depósitos espeleotémicos (Karst de la Cueva del Reguerillo). En ellas se obtuvieron datos sobre la evolución del paisaje y del clima, los travertinos y espeleotemas son indicadores de clima cálido s.l. que de forma abreviada son: O Mediante la geomorfología y dataciones (paleomagnetismo, U/Th, Resonancia de espín Resumen electrónico y racemización de aminoácidos), se determinó las historia fluvial de los travertinos de Priego y Río Blanco así como del Karst de la Cueva del Reguerillo donde, además, se dataron un paleosismo y fenómenos de neotectónica. La data más antigua obtenida mediante Resonancia de espín electrónico fue 950ka, mientras que mediante racemización de aminoácidos se dataron depósitos de más de 750ka. Mediante dataciones, sedimentología, análisis de isótopos estables y palinología se determinaron aspectos de la evolución climática de algunas áreas de la Península Ibérica. La correlación entre palinología e isotopía permitió la validación de algunos de los resultados. También se obtuvieron datos cualitativos sobre input hidraúlicos a los sistemas fluviales o kársticos

The 5′ Leader of the mRNA Encoding the Mouse Neurotrophin Receptor TrkB Contains Two Internal Ribosomal Entry Sites that Are Differentially Regulated

A single internal ribosomal entry site (IRES) in conjunction with IRES transactivating factors (ITAFs) is sufficient to recruit the translational machinery to a eukaryotic mRNA independent of the cap structure. However, we demonstrate that the mouse TrkB mRNA contains two independent IRESes. The mouse TrkB mRNA consists of one of two 5′ leaders (1428 nt and 448 nt), both of which include the common 3′ exon (Ex2, 344 nt). Dicistronic RNA transfections and in vitro translation of monocistronic RNA demonstrated that both full-length 5′ leaders, as well as Ex2, exhibit IRES activity indicating the IRES is located within Ex2. Additional analysis of the upstream sequences demonstrated that the first 260 nt of exon 1 (Ex1a) also contains an IRES. Dicistronic RNA transfections into SH-SY5Y cells showed the Ex1a IRES is constitutively active. However, the Ex2 IRES is only active in response to retinoic acid induced neural differentiation, a state which correlates with the synthesis of the ITAF polypyrimidine tract binding protein (PTB1). Correspondingly, addition or knock-down of PTB1 altered Ex2, but not Ex1a IRES activity in vitro and ex vivo, respectively. These results demonstrate that the two functionally independent IRESes within the mouse TrkB 5′ leader are differentially regulated, in part by PTB1

Evaluación cuantitativa del impacto ambiental en la selección del emplazamiento del nuevo vertedero de residuos sólidos urbanos de Málaga

In this paper the methodo/ogy used in the viability study of a new controlled landfil/ of metropolitan solid wastes site, in the city of Malaga, is briefly exposed. lt is undertaken as an integral study where all the conditioning parameters, the environmental as well as the technical ones, are included. The site selection is carried out by means of a quantitative evaluation of the viability of each one of the alternatives. The conditioning parameters are hierarchized and a viability index is define

Estructuras alpinas internas al Paleozoico del Manto de Gavarnie, Pirineo Central

In the paleozoic materials of the Iower part of the Gavarnie Nappe «retronormal» faults appear, which are compatible with the tangencia/ compressives stresses and transalation movement of the nappe to the south. In the upper part of the nappe (Cretaceous and Paleogenous materials) a tectonic stack with increasing thrusting from bottom to top, is produced. Both behaviours can be explained by the ratio between tangencia/ comprensive stress and lithological loa

The three α₁-adrenoceptor subtypes show different spatio-temporal mechanisms of internalization and ERK1/2 phosphorylation

We analyzed the kinetic and spatial patterns characterizing activation of the MAP kinases ERK 1 and 2 (ERK1/2) by the three α1-adrenoceptor (α<sub>1</sub>-AR) subtypes in HEK293 cells and the contribution of two different pathways to ERK1/2 phosphorylation: protein kinase C (PKC)-dependent ERK1/2 activation and internalization-dependent ERK1/2 activation. The different pathways of phenylephrine induced ERK phosphorylation were determined by western blot, using the PKC inhibitor Ro 31-8425, the receptor internalization inhibitor concanavalin A and the siRNA targeting β-arrestin 2. Receptor internalization properties were studied using CypHer5 technology and VSV-G epitope-tagged receptors. Activation of α<sub>1A</sub>- and α<sub>1B</sub>-ARs by phenylephrine elicited rapid ERK1/2 phosphorylation that was directed to the nucleus and inhibited by Ro 31-8425. Concomitant with phenylephrine induced receptor internalization α<sub>1A</sub>-AR, but not α<sub>1B</sub>-AR, produced a maintained and PKC-independent ERK phosphorylation, which was restricted to the cytosol and inhibited by β-arrestin 2 knockdown or concanavalin A treatment. α<sub>1D</sub>-AR displayed constitutive ERK phosphorylation, which was reduced by incubation with prazosin or the selective α<sub>1D</sub> antagonist BMY7378. Following activation by phenylephrine, α<sub>1D</sub>-AR elicited rapid, transient ERK1/2 phosphorylation that was restricted to the cytosol and not inhibited by Ro 31-8425. Internalization of the α<sub>1D</sub>-AR subtype was not observed via CypHer5 technology. The three α<sub>1</sub>-AR subtypes present different spatio-temporal patterns of receptor internalization, and only α<sub>1A</sub>-AR stimulation translates to a late, sustained ERK1/2 phosphorylation that is restricted to the cytosol and dependent on β-arrestin 2 mediated internalization

Aportaciones al conocimiento de la evolucion paleoclimatica y paleoambiental en la Peninsula Iberica durante los dos ultimos millones de aNos a partir del estudio de travertinos y espeleotemas

Centro de Informacion y Documentacion Cientifica (CINDOC). C/Joaquin Costa, 22. 28002 Madrid. SPAIN / CINDOC - Centro de Informaciòn y Documentaciòn CientìficaSIGLEESSpai