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21.
Vera, E.I. iFirstarticle. Millerocaulis tekelili sp. nov., a new species of osmundalean fern from the Aptian Cerro Negro Formation (Antarctica). Alcheringa, 1–10. ISSN 0311-5518.

Ezequiel Ignacio Vera [evera@macn.gov.ar] División Paleobotánica, Museo Argentino de Ciencias Naturales 'Bernardino Rivadavia', Av. Angel Gallardo 470, C1524DJR, Buenos Aires, Argentina. Also affiliated with Área de Paleontología, Departamento de Ciencias Geológicas, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Pabellón II, Ciudad Universitaria, C1428EGA, Buenos Aires, Argentina. Received 29.10.2010, revised 14.3.2011; accepted 24.3.2011.

A new species of the osmundalean fossil morphogenus Millerocaulis Tidwell emend. Vera, Millerocaulis tekelili sp. nov. is defined, based on several permineralized stems recovered from exposures of the Lower Cretaceous Cerro Negro Formation on Livingston Island, South Shetland Islands, Antarctica. This new species is characterized by the presence of an ectophloic–dictyoxylic siphonostele, inner parenchymatic and outer sclerotic cortices, heterogeneous sclerotic ring in the petiole bases, absence of sclerenchyma associated with the petiolar xylem trace, petiolar inner cortex with sclerenchyma strands and stipular wings having a large sclerenchyma bundle and several smaller ones. The presence of non-homogeneous sclerotic rings in the petiole bases allows this new species to be clearly distinguished from other Antarctic Millerocaulis, and suggests that it may represent an intermediate form in the evolutionary lineage leading from Millerocaulis to subgenus Claytosmunda of Osmunda.  相似文献   
22.
Over the last twenty‐five years an anti‐Keynesian orthodox approach has envisaged a prominent role for reductions in fiscal deficits in developing countries. Expansionary fiscal policies have been said to result in excessive expansion of aggregate demand leading to current account deficits and inflation, as well as displacing private investment, thereby inhibiting output stabilization and employment recovery. Moreover, chronic fiscal deficits are supposed to be associated with high and explosive debt/GDP ratios. The purpose of this article is to assess the theoretical adequacy of the orthodox approach in the context of developing countries. The author clarifies some common misunderstandings and finds that none of the conventional arguments against fiscal activism is wholly convincing. At the heart of the debate lies the question of assumptions, economic structure and causation mechanisms. The orthodox stories regarding the macroeconomic effects of fiscal policy very often do not go beyond the simple monetarist assumptions or seek to verify the implications against the existing experiences and empirical data from developing countries.  相似文献   
23.
Two adjacent chambers of the cave of La Chaise, Grotte de Bourgeois-Delaunay (B-D) and Grotte Suard, have been studied. Both were partly filled with detrital sediments containing lower and middle Palaeolithic artifacts and skeletal remains of pre-Neanderthalian hominids. Layers of stalagmitic calcite occur interstratified in the sediments of both chambers. Dates obtained by 230Th/234U ratios have provided a time scale for hominid and cultural evolution as represented in this cave.In B-D the lower travertine rests on a breccia containing cranial remains of juvenile Neanderthals. The base of the travertine dates to 151 ± 15 Ky (Ky = 1000 years BP); the top of the travertine yields a date of 112±5 Ky. The travertine contains pollen of an interglacial flora. Overlying detrital sediments 1·2 m in thickness contain artifacts transitional from Acheulian to Mousterian industries. They are capped by a travertine (Layer 7) whose base is dated at 100±6 Ky, and which is capped by stalagmites ranging in age down to 58±7 Ky. Overlying the travertine is sediment containing first Mousterian, and then Aurignacian artifacts.Near the base of the sediments filling Grotte Suard is a stalagmite layer dated to 249±30 Ky. It contains interglacial pollen and presumably dates to the beginning of the isotope stage 7 interglacial. Neanderthaloid hominid teeth and cranial fragments are found scattered through the overlying sediments, up to a capping stalagmitic layer whose base is dated at 101±7 Ky. The best described hominids from Suard are from a section that was probably overlying the capping stalagmite. The capping stalagmite is temporally correlated with layer 7 of B-D.  相似文献   
24.
25.
High-resolution stable oxygen isotope analysis of the bivalve Saxidomus gigantea from shell midden sites was applied to identify seasonal patterns of resource procurement on the central coast of British Columbia, Canada. A total of 90 archaeological shells were examined from eight distinct sites spanning a 4500-year period. Combining micro-growth pattern analysis with high-resolution stable oxygen isotope sampling allows for a precise season of collection to be determined in estuarine bivalves recovered from archaeological sites. The results of the stable oxygen isotope analysis provide insights into seasonally structured harvest of S. gigantea (butter clam), which is associated with different types of sites. The results show a variety of patterns, including multi-seasonal collection, intensive seasonal harvesting and casual, supplemental use of butter clams at different locations.  相似文献   
26.
New Spain was a land of opportunity for the missionary as well as the conquistador. The controversial proposal to found a convent for women of the indigenous elite illuminates the redefinition of notions of gender and race. Examining testimonies on this question written by priests, this article charts how they transform material that would normally have been presented as hagiography into narratives of a more general nature, and argues that this rhetorical shift contributed to a kind of writing on the Indies which not only shared the comparative and epistemological stakes of ethnography but also considered issues of gender.  相似文献   
27.
Vera Chouinard  Ali Grant 《对极》1995,27(2):137-166
This paper challenges current constructions of “the project” in radical geography by examining the phenomenon of “missing sisters.” We discuss the social construction of lesbians and disabled women as invisible “others” and how this is manifest in Geography. We argue that disabled women and lesbians have had their experiences and lives marginalized; both in the geographic literature and through practices of exclusion. We call for a reconstructed radical geography which includes lesbians and disabled women, on their own revolutionary terms, in the production of knowledge and in political practice. Such an inclusionary project will enrich our understanding of geographic processes and strengthen our efforts to build political strategies of resistance to contemporary forms of oppression and marginalization.  相似文献   
28.
We have obtained ESR ages on 18 teeth from archaeological levels AH16-AH27 exposed at the east profile in compartment E at Karaïn Cave. This sequence exhibits a transition in lithic assemblage from a Classic Charentian to a Karaïn (Zagros-type) Mousterian between levels AH27 and AH25, and two calcite-cemented soils at levels AH22 and AH16 which have been interpreted as climatic warm phases. Since we found no systematic increase in tooth ages with depth, we assigned this sequence a mean early uptake (EU) age of 108 ± 23 ka and mean linear uptake (LU) age of 121 ± 27 ka, on the basis of 37 subsamples from 16 teeth. In this site, the precision of individual tooth ages suffered little from the problems associated with uranium uptake. However, this advantage was offset due to uncertainties arising from the rather inhomogeneous nature of the enclosing strata which contained various sizes of limestone blocks with intervening sediment. This led to difficulties in ascribing a precise annual gamma radiation dose to individual teeth in such a "lumpy" gamma radiation field. Considerable scattering of the individual tooth ages occurred mainly because the annual gamma dose comprised greater than 50% of the total annual dose to the individual teeth. On the basis of the ESR dating results, we infer that deposition of the two different lithic assemblages and both the penultimate and the final climatic warm phases at Karaïn probably occurred during oxygen isotope stage 5. We also conclude that these lithic assemblages are significantly different than contemporaneous Levantine Mousterian industries which occur about 700 km to the southeast.  相似文献   
29.
This paper studies the link between knowledge, innovation, and growth in European regions using nonparametric methods. Our findings suggest that knowledge inputs and the share of innovative firms have a heterogeneous and nonlinear relationship with growth. This evidence has been exploited to examine the consequences of alternative policies using a counterfactual estimation setup, the results of which imply that increasing the formal knowledge base may be optimal in most regions. Less knowledge and innovation intensive regions will also benefit from a higher innovation potential and from a trustworthy and entrepreneurial economic environment.  相似文献   
30.
Abstract

Taking into account the course of cultural policy in democratic Portugal, and against the backdrop of the international crisis of 2008 and the sovereign debt crisis of 2011, this article seeks to interpret recent changes in the cultural sector in Portugal. Using both qualitative and quantitative methods it focuses on three main aspects: institutionalisation of democratic cultural policy; government funding; cultural organizations and facilities. The 2008 crisis put an end to a period in which investment tended to grow. We place Portugal in the broader European context, concluding that the Portuguese cultural scene may once again diverge from that of other European countries.  相似文献   
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