2,085 research outputs found
Capas de Tormentas (tempestitas) en el Jurásico del Subbético Externo (Cordilleras Béticas)
Se estudian niveles de tempestitas calcáreas en el Dogger y Malm del Subbético Externo. Se describen las secuencias de estructuras internas y se interpreta su génesis en relación con tormentas tropicales o huracanes, lo que concuerda con la paleogeografía y paleolatitud admitida para el Jurásico
Bauxitas kársticas jurásicas en la zona subbética (Zarzadilla de Totana, prov. de Murcia, sureste de España): Interpretación paleogeográfica
Los yacimientos de bauxitas de Zarzadilla de Totana (Murcia) selocalizan en materiales jurásicos del Subbético interno. Las bauxitas se emplazan rellenando cavidades kársticas en el seno de calizas del Lias infradomerense indicando claramente una etapa de emersión de un umbral pelágico que pudo durar parte del Lias superior y del Dogger
Turbiditas carbonatadas del Cretácico inferior en el Arroyo Bercho, Prebético de Jaén: Interpretación genética e implicaciones paleogeográficas
[ES] El análisis de las características sedimentarias de las turbiditas
carbonatadas permite precisar la interpretación paleogeográfica del
Prebético de Jaén, durante el Cretácico. Se pueden distinguir dos
asociaciones de facies: a) Turbiditas de estatificación fina, intercaladas
en abundante sedimento pelágico, e interpretadas como facies
de borde de lóbulo. b) Cuerpos turbidíticos lenticulares interpretados
como lóbulos de depósito formados por agradación. Aparecen
asociadas a una serie depositada en una cuenca que progresivamente
se fue haciendo más somera y que terminó con la implantación de
una plataforma carbonatada en el Cenomanense. Se calcula que el
depósito de las turbidítas debió realizarse a unos pocos centenares
de metros de profundidad.[EN] The analysis of the sedimentary characteristics of the carbonate
turbidites allows to accurate the paleogeographic interpretation of
the Prebetie of laen. Two types of facies associations can be distinguished: a) Thin bedded turbidites> as intercalations into mainly hemipelapic
sediments, interpreted as lobe fringe facies, b) Lents like
turbiditie bodies corresponding to agradational depositional lobes.
They occur associated to an shallowing upward sequence ending
with Cenomanian carbonated platform facies. The turbiditic deposit
supodselly took place in a few hundreds meters deep sedimentary
basin.Trabajo patrocinado por la C.A.I.C.Y.T.,
dentro del proyecto «El Mesozoico de las Cordilleras Béticas» realizado
en este centro del C.S.I.C.Peer reviewe
Glauconite and phosphate peloids in Mesozoic carbonate sediments (eastern Subbetic Zone, Betic Cordilleras, SE Spain)
13 páginas, 4 figuras, 3 tablas.Glauconite and Ca phosphate peloids occur in Jurassic and Cretaceous bioclastic carbonate rocks from pelagic swell sequences of the Algayat-Crevillente Unit (Subbetic Zone). The size and morphology of the peloids are controlled by the bioclasts. The glauconite in both stratigraphic positions is K rich (>0.69 atoms p.f.u.) and shows well-defined 10 Aa lattice fringes. Poorly crystalline areas with a composition of Fe-smectite are found within the peloids, indicating the nature of the glauconitic precursor. This precursor would be formed in the shielded microenvironments of the bioclast and later transformed to glauconite by equilibration of peloids with sea water that culminated with the crystallization of a phosphatic phase. The greater presence of smectite areas in the Jurassic peloids and the lower K contents (0.69-0.81) of these glauconites, compared with the Cretaceous glauconites (0.81-0.89) can be explained by the calcitic early diagenetic cementation which stopped the process of glauconitization.Financial support was
provided by the Research Groups 4065 and 4135 of
the Junta de Andalucía and the Projects PB92-0961 and
PB93-1150-CO2 of DGICYT.Peer reviewe
Prospects for the rapid detection of mealiness in apples by nondestructive NMR relaxometry
The potential of nuclear magnetic resonance (NMR) relaxometry for quantitative evaluation of apple mealiness has been investigated. The degree of "mealiness" was defined by several mechanical techniques, including penetration, compression and shear rupture as well as by the BRIX (soluble solids) and juiciness levels. These data were correlated with both magnetic resonance imaging (MRI) and NMR water proton transverse relaxation time measurements on a fruit-by-fruit basis. It was found that increasing mealiness caused a systematic increase in the transverse relaxation rate. The potential for rapid, on-line NMR/MRI detection of apple mealiness is discussed
La formación radiolarítica Jarropa: definición y significado en el Jurásico Subbético (Cordillera Bética)
The Jarropa Radiolarite Formation is defined formally, for the first time, according to the international guide of stratigraphic nomenclature, and the holostratotype and two parastratotypes are described. This is a very characteristic Jurassic unit of the Subbetic (Betic Cordillera) in which point out the presence of radiolarite levels, together with siliceous marlstones, marls and clays. Two members are differentiated: a lower member of green, radiolarites and siliceous marls, and an upper member of red, siliceous clays and marls, both being recognizable in most of the outcrops. The age of this formation in the holostratotype, known mainly from the study of their radiolarians, is Late Callovian-Oxfordian. In other stratigraphic sections (including some parastratotype) is verified that the exact age of the bottom of the formation, and of the boundary between the two before described members are heterochronous, within the Uppermost Bajocian-Lowermost Kimmeridgian. They are pelagic sediments, deposited during the expansive phase of the Southern Iberian Continental Paleomargin, in areas far from the continent with thin continental crust. They have a great analogy with deposits outcropping in others Mediterranean Alpine domains (Apennines, Alps, Dinarids, etc.) also accumulated during Jurassic extensive phases of continental margins adjacent to the Tethys. The depositional bathymetry is estimated in a few hundreds of meters, without a necessary relation with the calcite compensation depth (CCD).Se define formalmente, por primera vez, la «Formación Radiolarítica Jarropa» de acuerdo con las normas internacionales de nomenclatura estratigráfica, y se describen el holoestratotipo y dos paraestratotipos. Se trata de una unidad litoestratigráfica muy característica del Jurásico del Subbético (Cordillera Bética) en la que destacan la presencia de niveles de radiolaritas, junto con margas y arcillas silíceas. Se diferencian dos miembros, uno inferior («miembro de radiolaritas y margas silíceas, verdes») y otro superior («miembro de arcillas y margas silíceas, rojas»), ambos reconocibles en la mayoría de los afloramientos. La edad de esta formación en el holoestratotipo, conocida a partir del estudio de los radiolarios, es Calloviense superior-Oxfordiense. Se constata que las edades del muro de la formación y del límite entre los dos miembros, en otras secciones estratigráficas son diferentes mostrando un carácter claramente heterócrono, dentro del intervalo Bajociense terminal-Kimmeridgiense basal. Se trata de sedimentos pelágicos, depositados en áreas alejadas del continente, durante la fase expansiva del margen continental sudibérico, con sustrato de corteza continental. Presentan una gran analogía con materiales que aparecen en diferentes dominios alpinos mediterráneos (Apeninos, Alpes, Dinárides, etc.) también depositados, durante el Jurásico, en fases de expansión de márgenes continentales adyacentes al Tethys. La batimetría de su depósito se estima en pocos centenares de metros, sin una necesaria relación con el nivel de compensación de la calcita (CCD)
Location of intertidal zones suitable for clam culture in the Piedras River (southwestern Iberian Peninsula)
Clam ongrowing in the intertidal zone of Huelva (southwestern Iberian Peninsula) is a fast-rising industry in the area. Therefore, it is necessary for the local authorities to regulate this activity. The success of seabed cultivation will largely depend on the selection of appropriate sites (e.g., substrate, exposure, seabed area, environmental requirements). The present study aimed to characterise and quantify the intertidal substrate suitable for bivalve culture in the Piedras River, in order to establish criteria for intertidal zone use. The results obtained showed that there are 694 525 m² that could be used for ongrowing the Manila clam Ruditapes philippinarum (Adamsampersand Reeve, 1850); of these, it is necessary to improve the substrate of 66 625 m², whilst 2 800 m² can be occupied immediately. The area for culture of the carpet shell Ruditapes decussatus (L., 1758) was estimated at 19 906 m² of the total area.El impulso que está recibiendo el engorde de almejas en la zona intermareal de los caños, esteros y estuarios de la provincia de Huelva, justificado por los buenos resultados obtenidos con la almeja japonesa Ruditapes philippinarum (Adamsampersand Reeve, 1850), se refleja en el aumento de solicitudes de autorizaciones y concesiones administrativas. Para la ordenación de la actividad es necesario, entre otras evaluaciones, caracterizar y cuantificar la superficie de la franja intermareal con potencialidad para el cultivo y establecer una escala que permita priorizar su aprovechamiento y las posibilidades de ocupación. Con los diferentes valores estimados analíticamente, las asignaciones empíricas y las ponderaciones correspondientes, se considera que en el río Piedras existen 69 425 m² de superficie susceptible de ser utilizada para el engorde de la almeja japonesa, de los que 19 906 m² podrían destinarse al de la almeja fina Ruditapes decussatus (L., 1758). Del total, 66 625 m² necesitarán enmiendas del sustrato y 2 800 m² son ocupables de forma inmediata.Instituto Español de Oceanografí
Origin of congenital coronary arterio-ventricular fistulae from anomalous epicardial and myocardial development.
Coronary Artery Fistulae (CAFs) are cardiac congenital anomalies consisting of an abnormal communication of a coronary artery with either a cardiac chamber or another cardiac vessel. In humans, these congenital anomalies can lead to complications such as myocardial hypertrophy, endocarditis, heart dilatation, and failure. Unfortunately, despite their clinical relevance, the aetiology of CAFs remains unknown. In this work, we have used two different species (mouse and avian embryos) to experimentally model CAFs morphogenesis. Both conditional Itga4 (alpha 4 integrin) epicardial deletion in mice and cryocauterisation of chick embryonic hearts disrupted epicardial development and ventricular wall growth, two essential events in coronary embryogenesis. Our results suggest that myocardial discontinuities in the embryonic ventricular wall promote the early contact of the endocardium with epicardial-derived coronary progenitors at the cardiac surface, leading to ventricular endocardial extrusion, precocious differentiation of coronary smooth muscle cells, and the formation of pouch-like aberrant coronary-like structures in direct connection with the ventricular lumen. The structure of these CAF-like anomalies was compared with histopathological data from a human CAF. Our results provide relevant information for the early diagnosis of these congenital anomalies and the molecular mechanisms that regulate their embryogenesis.The authors thank Dr. A. Rojas (CABIMER, Sevilla, Spain) and Prof. Thalia
Papayannopoulou (University of Washington, WA, USA) for sharing with us the G2-
Gata4-Cre and Itga4-floxed mouse lines, respectively. We also thank Vanessa
Benhamo (Institut Imagine) for her expert support with HREM. Finally, we thank all
members of “DeCA” laboratory (University of Málaga, Málaga, Spain), and the “Heart
Morphogenesis” laboratory (Institut Imagine and Institut Pasteur, Paris, France) for
their help and fruitful discussions on this paper. This work was supported by the
Spanish Ministry of Science, R+D+i National Programme [grants RTI2018-095410-RBI00 and PID2021-122626-OB-I00], Spanish Ministry of Science-ISCIII [grant number
RD16/0011/0030], and University of Málaga [grant number UMA18-FEDERJA-146] to
[JMPP]; Consejería de Salud y Familias, Junta de Andalucía [grant number PIER-0084-
2019] to [JAGD]; University of Málaga [grant number I Plan Propio-UMA-A.4] to [ARV];
Spanish Ministry of Science, Innovation, and Universities (MCIU) (CIBER CV) [grant
numbers PID2019-104776RB-I00 and CB16/11/00399] to [JLDLP].S
Deliverable D4/5: Global climatic characteristics, including vegetation and seasonal cycles over Europe, for snapshots over the next 200,000 years. Work Package 2, Simulation of the future evolution of the biosphere system using the hierarchical strategy. Modelling Sequential Biosphere Systems under Climate Change for Radioactive Waste Disposal (BIOCLIM)
The aim of the BIOCLIM project is to develop and
present techniques that can be used to develop
self-consistent patterns of possible future
climate changes over the next million years (climate
scenarios), and to demonstrate how these climate
scenarios can be used in assessments of the long-term
safety of nuclear waste repository sites.
Within the project, two strategies are implemented to
predict climate change. The first is the hierarchical
strategy, in which a hierarchy of climate models is used
to investigate the evolution of climate over the period of
interest. These models vary from very simple 2-D and
threshold models, which simulate interactions between
only a few aspects of the earth system, through general
circulation models (GCMs) and vegetation models,
which simulate in great detail the dynamics and physics
of the atmosphere, ocean, and biosphere, to regional
models, which focus in particular on the European
region and the specific areas of interest. The second
strategy is the integrated strategy, in which
intermediate complexity climate models are developed,
and used to consecutively simulate the development of
the earth system over many millennia. Although these
models are relatively simple compared to a GCM, they
are more advanced than 2D models, and do include
physical descriptions of the biosphere, cryosphere,
atmosphere and ocean.
This deliverable, D4/5, focuses on the hierarchical
strategy, and in particular the GCM and vegetation
model simulation of possible future climates.
Deliverable D3 documented the first step in this
strategy. The Louvain-la-Neuve 2-D climate model
(LLN-2D) was used to estimate (among other variables)
annual mean temperatures and ice volume in the
Northern Hemisphere over the next 1 million years.
It was driven by the calculated evolution of orbital
parameters, and plausible scenarios of CO2
concentration. From the results, 3 future time periods
within the next 200,000 years were identified as being
extreme, that is either significantly warmer or cooler
than the present. The next stage in the hierarchical
strategy was to use a GCM and biosphere model, to
simulate in more detail these extreme time periods
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