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21.
David Martín‐Barroso Juan A. Núñez‐Serrano Francisco J. Velázquez 《Journal of regional science》2015,55(5):708-735
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
22.
The Middle Formative Cemetery of Topater 1 (ca. 500 bc –100 ad ), located in the oasis of Calama, Northern Chile, presents an unusually diverse array and quantity of funerary offerings, distributed among the graves of more than 200 individuals. Among the offerings are the remains of several mummified camelids and camelid skeletal elements, primarily distal extremities and artefacts made from the bones of these animals. Taking only the first skeletonised anterior and posterior phalanges of Topater 1 camelids, we conducted univariate and multivariate osteometric analyses in order to assign the sample to the appropriate taxonomic groups. At the same time, we described all osteopathologies registered for the extremities in the collection. Of the 45 phalanges measured, 30 were of similar or greater size than contemporary reference llamas. Fourteen of the 164 samples of bone extremities presented pathologies, most of them first phalanges. These abnormalities included different degrees of exostosis and, less commonly, eburnation and lipping. Considering both lines of evidence, we conclude that the llamas sacrificed at the Topater 1 cemetery correspond to, at least, two very large and robust cargo llama morphotypes. When living, these animals would have transported goods as part of the intense exchange activity that was taking place during this period in the region extending from the Pacific coast to Northwest Argentina and perhaps even beyond. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
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24.
Patricio E. Pérez Francisco J. Martínez Juan de Dios Ortúzar 《Journal of regional science》2003,43(4):771-789
Abstract We formulate a microeconomic model of residential location choice behavior as an aggregate of the individual behaviors of household members, subject to individual time constraints and a common income budget. A simplified version of the model is estimated from stated preference rank‐order data, yielding a function that may be interpretated as a conditional indirect utility function. We consider Box‐Tukey transformations, segmentation by income class, and a consistent treatment of data at different rank depths using the simultaneous mixed‐estimation method. Measures of the household's willingness‐to‐pay (through rents) for reducing travel times to work and study in the short run, are interpreted as subjective values of time and compared with such values derived from mode choice models. Our results are plausible, and consistent with recent findings showing that the short‐run benefits of transport projects derived by transport models are larger than benefits measured at the land use system. 相似文献
25.
Francisco L. Prez 《Geography Compass》2009,3(5):1774-1803
This study reviews several effects stones have on slope geomorphic processes and plant distribution at high elevations, with emphasis on low‐latitude mountains and volcanic environments and rosette plants. It begins by considering how vegetation becomes established on relatively stable footslopes and the principal influences that outcrops and isolated boulders have on slope movement and vegetation development, moves to a comparison of the principal geomorphic processes affecting stone‐covered slopes and the disturbance agents influencing fine‐sediment zones that are devoid of clasts. The significance of stones for plant survival in areas subjected to frost activity, the strategies displayed by plants growing in unstable talus zones and the impacts stones have on plant development and slope dynamics are also considered. The study concludes by examining the role stones play in providing safe sites for plant development and the expansion of ecological niches, and with some speculations on possible future research directions. 相似文献
26.
Francisco M. Veloso 《Journal of regional science》2006,46(4):747-772
ABSTRACT In industrializing regions, foreign investments often generate spillovers through regional backward links. This situation may create a gap between private and social valuations of resources, resulting in a level of local content below what would be optimal for the economy. This situation creates an opportunity for the enactment of domestic content regulations. This paper presents a model to understand how these policies condition the decisions of the economic agents and affect economic welfare. Then, it simulates the model using a case study of the automotive sector. Results suggest that, in certain conditions, this local content regulation can be welfare enhancing. 相似文献
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Francisco Curate Andreia Perinha Ana Maria Silva Eugnia Cunha Cludia Umbelino Catarina Nogueira 《International Journal of Osteoarchaeology》2019,29(1):73-81
There has been considerable progress in recent years in our understanding of the patterns of cortical bone loss in the second metacarpal in archeological skeletal samples. Nevertheless, cortical data from reference skeletal collections are insufficient, and the possible connection of metacarpal cortical parameters with osteoporotic fractures has not been thoroughly addressed. As such, this article aims to identify and explain sex‐specific and age‐associated metacarpal cortical bone loss in a large sample (N = 302; females: 154/males: 148) from the Coimbra Identified Skeletal Collection. Another objective is to evaluate the association of cortical and demographic features with osteoporotic fractures. Age‐related endocortical bone loss is significant in women but not evident in men. Periosteal accretion of the bone is absent in both sexes. Overall, there is a net loss of the cortical bone in women, whereas cortical bone strength seems to be preserved in men. The prevalence of osteoporotic fractures is similar in both sexes, with age at death significantly influencing the probability of exhibiting a fracture. Metacarpal cortical index does not seem to be an independent risk factor for osteoporotic fractures in this sample. 相似文献
29.
The use of renewable hydraulic energy sources by mankind most likely has its origins in the development of the watermills. To understand the functioning of these mills, this article first reviews, through the analysis of different bibliographical sources, the technical evolution of the machinery used since the appearance of the first watermills to grind cereal grain in the 1st century bc.
Secondly, a particular area of the south-west of Spain, Alcalá de Guadaíra, has been selected for study, whose strategic location as well as its hydrological characteristics gave rise, firstly, to an intensive milling industry, and, later, a famed baking industry, from the late Middle Ages until recent decades. The huge development of these two industrial activities has made Alcalá de Guadaíra an exceptional example in Spain, with 40 watermills in the early 18th century.
Extensive work on site allowed the analysis of the state and types of watermills that still exist in this area, identifying their similarities and differences. Unfortunately, after they fell into disuse, only 28 of these mills remain today; 12 of them are in a relative good state of preservation, seven in an alarming state of ruin and, of the other nine, only some unrecognisable vestiges remain. Some of these mill buildings have been restored recently, although their machinery is missing. Only from old photographs or by visiting mills restored in other areas is it possible to determine how these watermills worked.
Due to the lack of financial resources to carry out physical restoration of the industrial heritage missing in these flour mills, a virtual model of one of them has been developed. This work provides, at least virtually, a reconstruction of the traditional mills which helps promote technological studies and shows how they worked, as part of virtual exhibitions. In addition, a computer application of augmented reality has been developed that any visitor can install on a mobile device to display the virtual reality of the machinery, generated by 3D models, so they can visualise the physical reality that they would have found in the mill. 相似文献
30.
Ramiro Barberena A. Francisco Zangrando Adolfo F. Gil Gustavo A. Martínez Gustavo G. Politis Luis A. Borrero Gustavo A. Neme 《Journal of archaeological science》2009,36(12):2666-2675
We synthesize and discuss available isotopic data on Holocene guanaco samples from southern South America, extending from Tierra del Fuego Island to northern Patagonia and the Pampean region. We evaluate temporal and spatial tendencies on the basis of 91 samples (mainly based on δ13Ccollagen values), presenting implications for paleodietary research in archaeology. We conclude that there are no strong correlations with latitude in the macro-spatial scale, while there is a set of interesting patterns at smaller regional scales. These patterns lead us to evaluate the role of ecologic and topographic variables (e.g. canopy effect, variations in altitude, ecotones) in structuring isotopic variability. Finally, on the basis of the present analysis we suggest a number of hypotheses and perspectives for the use of stable isotopes as geographic tracers of guanaco distribution in the past, and specific implications for the paleodietary study of human samples. 相似文献