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71.
This paper evaluates the impact of accessibility on the productivity of Spanish manufacturing firms. We suggest the use of accessibility indicators of workers and commodities, integrating transport, land use, and individual components, computing real distances or traveling times using the Spanish full road network. Estimated firms’ total factor productivity is explained as a function of the accessibility indicators and additional control variables. Results evidence the crucial role on firms’ productivity to the accessibility of commodities and to a slightly lesser extent the workers.  相似文献   
72.
Particle-induced X-ray emission (PIXE), X-ray diffraction (XRD), electron microprobe analysis (EDS) and scanning electron microscopy (SEM) analytical techniques were used to characterize surface paints in pre- and post-fired Aguada Portezuelo decorated pottery. Surface paintings in black, white, red, brown, burgundy and ochre were analysed. Major, minor and trace elements were detected by PIXE, whereas XRD and SEM-EDS gave information on the main mineral phases and the characteristic morphology for each analysed pigment. The results obtained indicate that the main colour groups can be easily discriminated by PIXE, and they are characterized by only one pigment for each colour: hematite (red) and manganese mineral oxides (black), respectively, whereas white pigments are characterized by calcite, ghelenite and gypsum.  相似文献   
73.
We analyse the isotopic values (δ13C, δ15N) of the diet of pre-Columbian horticulturalist populations from tropical and subtropical areas of southeastern South America, belonging to the Guarani and Taquara archaeological units. The data indicate different trends in each one (T?=?4.21; P?=?0.0004), showing a mixed diet with maize consumption in the Guarani samples (δ13Cco?=??15.5?±?1.8‰; δ13Cap ?10.4?±?0.8‰) and a depleted one in the Taquara ones (δ13Cco ?18.2?±?1.7‰; δ13Cap ?11.9?±?0.9‰), with a significant internal dispersion in both populations. The first population has higher nitrogen values (δ15N 11.1?±?0.6‰) compared to the Taquara samples (δ15N 9.3?±?1‰), suggesting a more carnivorous diet. The recognition of these pre-Columbian mixed diets involves the identification of maize cultivation on the Atlantic side of the southernmost area of South America (Parana Delta, 34° SL). Through the analysis of δ18O we have identified two isotopic ecozones, the first along the Paraná River Valley, with an average value of δ18O ?3.7?±?0.5‰ (CV?=?13.5%; CI?=??3.83 / ?3.16), and the second one, located in the Planalto of southern Brazil (Araucaria Forest), with a mean value of δ18O ?1.5?±?0.3‰ (CV?=?16.5%; CI?=??1.69 / ?1.29). The isotopic data (δ13C, δ15N and δ18O) suggest human movements between these two ecozones.  相似文献   
74.
75.
López-Gappa, J., Pérez, L.M. & Griffin, M. February 2017. First record of a fossil selenariid bryozoan in South America. Alcheringa XX, xxx-xxx. ISSN 0311-5518.

Selenariidae Busk 1854 (Bryozoa) is considered endemic to Australia and New Zealand. Here we describe a new species of Selenaria Busk 1854 from the lower Miocene Monte León Formation (Patagonia, Argentina). Selenaria lyrulata sp. nov. is characterized by autozooids with a lyrula-like, anvil-shaped cryptocystal denticle, opesiular indentations and lateral condyles, as well as avicularia with a shield of fused costae. This is the first record of a selenariid bryozoan in South America.

Juan López-Gappa [] CONICET—Museo Argentino de Ciencias Naturales. Av. Ángel Gallardo 470, C1405DJR, Ciudad Autónoma de Buenos Aires, Argentina; Leandro Martín Pérez [] and Miguel Griffin [], CONICET—División Paleozoología Invertebrados, Museo de La Plata. Paseo del Bosque s/n, B1900FWA, La Plata, Argentina.  相似文献   

76.
There has been noticeable development in the protection of linear infrastructure by UNESCO, whether on its cultural, technological or historical merits. However, with the exception of other means of transport incorporated within the field of industrial archaeology or recognised by the CIIC under the category of cultural routes, little or no consideration has been given to roads built from the mid-eighteenth century to the early part of the twentieth century. In view of this situation, this paper has the following aims. Firstly, to define the concept of ‘modern road’ and provide a brief analysis of the historical development and current situation of the same. Secondly, to assess the main contributions made to date regarding the heritage dimension of modern roads. Thirdly, to reconstruct the process of defining linear cultural landscapes, historic transportation corridors, cultural routes and heritage canals, railways and roads, in accordance with the considerations raised by ICOMOS and UNESCO. Finally, to contribute to the debate on the definition, characterisation and assessment of modern roads as world heritage assets, both intrinsically and in relation to established heritage categories.  相似文献   
77.
It took Alonso de Ercilla (1533–1594) thirty years to finish La Araucana, a first-person narrative epic poem about the brutal war of Arauco, in southern Chile, and one of the most canonical texts of colonial Latin America. By focusing on a crucial episode of Ercilla's eyewitness account, this essay revisits a number of scholarly discussions that have been central for our understanding of the text. First, it takes into consideration previous scholarship overlooked by specialists, as well as hitherto unstudied copies of the poem, in order to offer a thorough reevaluation of the textual and editorial history of the poem. Moreover, it explores the frontier as a chronotope and as a locus of enunciation for colonial epic, a space that is also crucial for Ercilla's carefully crafted authorial persona. Finally, it interrogates the ways in which the discursive representations of colonial frontier spaces were mediated by the material practices of early modern book production, arguing for a more fruitful relation between ecdotics and poetics, between material bibliography and theories of authorship and textuality in our approaches to colonial texts.  相似文献   
78.
Despite recent emphases on both environmental archaeology and practice theory in archaeology, the two are rarely combined. In this paper, we illustrate a genealogies of environmental practice approach that seeks to understand how human actions grounded in familiar repertoires make sense of environmental and political economic change. Employing archaeobotanical and zooarchaeological data, we first examine taxon-specific genealogies of practice and then compare them to one another as well as to broader climatic, political, and economic contexts of the last millennium in Banda, west central Ghana. In focusing on the interactivities between different kinds of data, we coax out the strategies used by Banda’s inhabitants to cope with fluctuating environmental and political conditions. We argue that during a several centuries long drought in the fifteenth to seventeenth centuries ad, Banda villagers took advantage of a diverse set of economic activities to cope with turbulence, but by the late nineteenth century, these opportunities had dwindled, diminishing the villagers’ practical options.  相似文献   
79.
Este artículo propone una lectura de la Historia del Reino de Quito en la América Meridional (1789), de Juan de Velasco, a partir de las ideas políticas y jurídicas de su autor. Sugiere abordar el tomo tercero de la Historia no solamente como un relato del declive social y económico que aqueja a la Audiencia de Quito, sino como un comentario a la crisis de gobernanza que, según Velasco, inicia con el ascenso de los Borbones al trono. La incapacidad jurídica de controlar la mestización de la sociedad y las desacertadas políticas de las autoridades peninsulares, resultan en la Rebelión de los Barrios de Quito, episodio que representa el clímax de las penurias que atraviesa el Reino y que le permite a Velasco cuestionar el modelo de gobierno establecido por los reformistas ilustrados, abogar por la necesidad de un gobierno criollo y restaurar la desgastada imagen de la Compañía de Jesús.  相似文献   
80.
ABSTRACT

This article analyses regional agency in the early phases of new path constitution. We argue that the early stages of new path constitution can be explained by both structural factors and the strong presence of agency. With a specific focus on agency, this article contributes to the literature by providing a study of the role of agency at different stages of path constitution. The study shows that two types of agency operate together. Public policy agency is carried out through a common thrust for policy tools that can enhance the room to manoeuvre together. In addition, strong entrepreneurial agency functions as a locomotive for other firms which are important trigger points, and pushes the process forward. These two forms of agency need to be interrelated to constitute new paths.  相似文献   
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