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ABSTRACT

Probably the most important Romanesque artwork in Spain, the Portal of Glory of Santiago de Compostela is essentially made in granite, the most abundant stone in the NW of Iberia, with the only exception of five marble pieces. Different hypothesis on the origin of these marbles have previously been proposed based on visual assessment or by directly assuming a local source. To shed light on their quarry provenance, a multi-analytical study was performed combining polarized-light optical microscopy, cathodoluminescence microscopy, XRPD, SEM-EDS and stable C and O isotopes. The comparison of the results with the available databases reveals the use of marbles from the Estremoz Anticline (Portugal) in the three exquisitely carved columns strategically placed in the central arcade, whereas the other two pieces are local marbles, illustrating a more complex consumption of this noble material than that initially expected.  相似文献   
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Abstract

This paper sets out to present geographies of gender and feminism in Mexico in order to identify some of the conceptual contributions, thematic axes and key problems within the field’s corpus of knowledge that, while widely-recognized internationally, is only beginning to develop in Mexico. I examine the academic production of feminist geography with an emphasis on the institutional contexts that may facilitate or perhaps impede putting such studies into practice in different institutions throughout the country. Additionally, I provide an account of the main objects of study that have contributed to configuring original, committed field research under the conditions of exclusion and marginality that women face on a daily basis.  相似文献   
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A new podocarpaceous conifer is described from the early Danian Salamanca Formation (southern Chubut, Patagonia, Argentina) based on compressions of leafy branches with cuticular remains. Kirketapel salamanquensis gen. et sp. nov. has amphistomatic, scale-like leaves with marginal frills distinguishable at the apex; stomata oriented randomly in relation to the major axis of the leaf with four to five subsidiary cells and extremely reduced Florin rings; and irregularly shaped epidermal cells. We compare K. salamanquensis with extant and extinct members of the imbricate-leaved podocarps, among which it closely resembles Florin’s Dacrydium group C genera (i.e., Lagarostrobos, Manoao, Lepidothamnus and Halocarpus). Among these genera, only Lepidothamnus has a living representative in South America, the Chilean L. fonkii, whose leaf macro- and micromorphological characters are described in detail for comparison. Overall, the Patagonian fossil species is most similar to the extant and extinct members of Lagarostrobos in its cuticular micromorphology; however, macromorphological characters, such as the leaf size, apex curvature and mode of flattening, clearly differentiate it from all four genera of Dacrydium group C. We include Kirketapel salamanquensis in a combined molecular and morphological phylogenetic analysis conducted under the maximum parsimony criterion. The new, early Paleocene fossil taxon is confidently recovered as part of the scale-leaved clade as defined herein, which also includes Halocarpus, Phyllocladus, Lepidothamnus, Parasitaxus, Lagarostrobos and Manoao, and it constitutes the oldest record known for the group by at least 17 million years as well as its first fossil occurrence outside Australasia, establishing a widespread Gondwanan history. Furthermore, based on its oldest locality of occurrence, K. salamanquensis shows that the divergence of the total group of the scale-leaved podocarps occurred by at least 65 million years ago, adding to the growing systematic knowledge of earliest Cenozoic macrofloras in the Southern Hemisphere.

Ana Andruchow-Colombo [] and Ignacio Escapa [] CONICET, Museo Paleontológico Egidio Feruglio Av. Fontana 140, Trelew 9100, Chubut, Argentina; Raymond J. Carpenter* [] School of Biological Sciences, University of Tasmania, Private Bag 55, Hobart, Tas. 7001, Australia; Robert S. Hill [] School of Biological Sciences and Environment Institute, University of Adelaide, Adelaide, SA 5005, Australia; Ari Iglesias [] CONICET, Instituto de Investigaciones en Biodiversidad y Medioambiente INIBIOMA-CONICET, Universidad Nacional del COMAHUE, Quintral 1250, San Carlos de Bariloche 8400, Río Negro, Argentina; Ana Abarzua [] Instituto de Ciencias de la Tierra, Facultad de Ciencias, Universidad Austral de Chile, Av. Rector Eduardo Morales Miranda 23, Valdivia 5090000, Región de los Ríos, Chile; Peter Wilf [] Department of Geosciences, Pennsylvania State University, University Park, PA 16802, USA. *Also affiliated with: School of Biological Sciences, University of Adelaide, Adelaide, SA 5005, Australia. Received 28.2.2018; revised 22.8.2018; accepted 24.8.2018.  相似文献   

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