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81.
Population decline is a key contemporary demographic challenge. Previous work has measured the national extent of population decline, and we know that it is more acute in Japan and Eastern Europe and is set to accelerate across many industrialized countries. Yet, little is known about the population trajectories leading to current trends of depopulation and their underpinning demographic and contextual factors. To address this gap, we aim to identify and characterize the different trajectories of depopulation in Spain from 2000 to 2020 at the small area level using sequence analysis, spatial autocorrelation analysis, decomposition techniques, and multinomial logistic modeling. We show that while Spain recorded an overall 17.2% national population growth between 2000 and 2020, 63% of municipalities experienced depopulation. We identify six trajectories of population decline, with a well-defined northwest-south divide. These trajectories include mostly rural municipalities, but also certain small- and medium-sized cities. Natural decline comprises the main demographic component underpinning differences in the extent of depopulation across trajectories, and international migration plays an important role in explaining transitions to decline since the financial crisis of 2008. Small and old populations, and, to a lesser extent, remoteness from cities are key features characterizing areas of high decline.  相似文献   
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African Archaeological Review - Recent archaeological excavations (2016–2019) in the city of Tamuda (northern Morocco) yielded evidence of commercial milling and bread-making facilities dated...  相似文献   
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Urban sprawl has a major impact on the environment, public health and the socio-economic evolution of cities. The causes are numerous, being mainly related to the generalized use of the automobile in modern cities. Urban sprawl has been especially relevant in US cities since the 1950s, rapidly spreading to other cities in the rest of the world. This paper studies the case of Spain using recent data. Spanish cities have grown rapidly over the 90s and 2000s. The country has completed the process of urbanization and has suffered the effects of a major real estate bubble. In this context, we are interested in measuring and explaining where and why urban sprawl has appeared in Spanish cities. Digital mapping carried out around the year 2000 providing full coverage of Spain is used to calculate an Urban Sprawl Index. It is applied to all urban areas and municipalities throughout the country, providing an objective, comparable measurement of sprawl and identifying which areas are most affected by this phenomenon. A second stage of analysis is conducted in an attempt to explain the causes of the differences in sprawl among Spanish cities with a regression model based on the literature. We have found that the cases most affected by sprawl are the latest urban developments on the Mediterranean coast as well as certain areas in the vicinity of large cities: the mountains to the north of Madrid and the coastline near Barcelona and Valencia. In some cases, urban sprawl is starting to become a problem for the environment and urban sustainability, with important consequences for the future evolution of the affected cities.  相似文献   
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Within an interdisciplinary project to study Istanbul’s Hagia Sofia, a georadar survey was carried out in the central nave to assess if the deformations of the structure previously observed could be related to a differential behavior of the subsoil caused by architectural remains underneath. This study faces an unusual challenge since it was necessary to study the space beneath the scaffolding placed for the restoration works. The survey of the central nave was successful and allowed the detection of remains of walls that probably formed the basement of a previous 18- by 22-m structure. In addition, another interesting feature was discovered 2 m below the marble mosaic in the southeastern part of the nave. Although it is not possible to define its function, it seems that there could be a close relationship between this 2- by 3-m buried structure and the marble mosaic in the floor surface. Although some structures were identified under the floor of Hagia Sofia, there are no major changes in the topography of the central nave floor.  相似文献   
88.
In a previous article, we presented an innovative method to analyze cut marks produced with metal tools on animal bones from a metrical and tridimensional perspective (Maté-González et al. 2015). Such analysis developed a low-cost alternative technique to traditional microscopic methods for the tridimensional reconstruction of marks, using their measurements and sections. This article presents the results of an experimental study to test this photogrammetric and morphometric method for differentiating cut marks generated with metal, flint, and quartzite flakes. The results indicate statistically significant differences among cut marks produced by these three types of raw material. These results encourage the application of this method to archeological assemblages in order to establish a link between carcass processing and lithic reduction sequences on different raw materials and also to define the kind of tools used during butchery.  相似文献   
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In this paper, the results of the archaeometric study of an assemblage of Late Roman amphorae, found in several contexts from the ancient city of Iluro (Mataró, Catalonia, Spain) and with a presumable origin in Roman Africa, is presented. A total of 57 samples have been analysed, by means of optical microscopy (thin-section analysis), X-ray fluorescence and X-ray diffraction, in order to obtain an integrated petrographic, chemical and mineralogical characterisation and, from this data, to shed light on their provenance. The results indicate the presence of a large number of fabrics, most of them with a Tunisian provenance; a fabric probably from Algeria was also found, as well as a few chemical-petrographic loners that should be related to a provenance out of Africa. Concerning the Tunisian fabrics, the comparison with data from production centres allows for a more precise provenance hypothesis for many of them. These results are useful for the study of the trade networks of Iluro in Late Antiquity, since they provide new evidence on the diversity of transport amphorae that were arriving to this urban centre in Hispania Tarraconensis, showing a more complex reality than initially suggested by the archaeological evidence.  相似文献   
90.
Torres-Martínez, M.A., Sour-Tovar, F. & Barragán, R., November 2017. Kukulkanus, a new genus of buxtoniin brachiopod from the Artinskian–Kungurian (Early Permian) of Mexico. Alcheringa 42, 268–276. ISSN 0311–5518.

Kukulkanus is the first genus of the tribe Buxtoniini recorded from rocks of the late Cisuralian (Artinskian–Kungurian). The Early Permian (Cisuralian) outcrops of the Santa Rosa Group, from southeastern Chiapas, are one of the most important marine Palaeozoic successions of Mexico. The Artinskian–Kungurian Paso Hondo Formation is the youngest unit in the succession and is dominated by massive limestone. Different marine invertebrates deposited in massive calcareous rocks characterize this formation. The buxtoniin Kukulkanus spinosus gen. et sp. nov. is reported from a single bed within the unit. The outcrops are located in southeastern Chiapas, very near the Guatemala–Mexico border. The lithological features and the preservation of fossils indicate that the fossil-bearing rocks were deposited in a low-energy open-waters paleoenvironment over the continental platform. Fusulinids, cephalopods and brachiopods previously described for the Paso Hondo Formation have been correlated with faunas of different coeval localities from Texas, New Mexico, Coahuila, Chiapas and Venezuela, regions that form part of the biotic Grandian Palaeo-Province.

Miguel A. Torres-Martínez [] Departamento de Paleontología, Instituto de Geología, Circuito de la Investigación Científica, Avenida Universidad No. 3000. Colonia Universidad Nacional Autónoma de México, Delegación Coyoacán, Cd. Mx. C.P. 04510, Mexico. Francisco Sour-Tovar [] Museo de Paleontología, Facultad de Ciencias, Universidad Nacional Autónoma de México. Av. Universidad No. 3000, Colonia Universidad Nacional Autónoma de México, Delegación Coyoacán, Cd. Mx. C.P. 04510, Mexico. Ricardo Barragán [] Departamento de Paleontología, Instituto de Geología, Circuito de la Investigación Científica, Avenida Universidad No. 3000. Colonia Universidad Nacional Autónoma de México, Delegación Coyoacán, Cd. Mx. C.P. 04510, Mexico.  相似文献   

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