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21.
The work focuses on the potential of structural and chemical examinations by scanning electron microscopy based methods for archaeometric studies on ceramics. Achieved by a single preparation technique (polished block sections), the feasibility and benefits of electron backscatter diffraction are demonstrated as case studies using polychrome examples of pre‐Columbian pottery (Wari, Moche and Cajamarca). Elemental and phase maps allow for separate consideration of clay and temper. Identification of mineral phases and intergrowths of temper particles provide information for clarifying clay procurement and firing techniques with respect to local versus non‐local pottery to enlighten trade relations, technological transfer and shared heritage of pre‐Columbian cultures.  相似文献   
22.
Consilience of genetics and archaeobotany in the entangled history of rice   总被引:3,自引:0,他引:3  
Major leaps forward in understanding rice both in genetics and archaeology have taken place in the past decade or so—with the publication of full draft genomes for indica and japonica rice, on the one hand, and with the spread of systematic flotation and increased recovery of archaeological spikelet bases and other rice remains on early sites in China, India and Southeast Asia. This paper will sketch a framework that coherently integrates the evidence from these burgeoning fields. This framework implies a reticulate framework in the phylogeny of early cultivated rice, with multiple starts of cultivation (two is perhaps not enough) but with the key consolidations of adaptations that must have been spread through hybridisation and therefore long-distance cultural contacts. Archaeobotanical evidence allows us to document the gradual evolutionary process of domestication through rice spikelet bases and grain size change. Separate trends in grain size change can be identified in India and China. The earliest centre of rice domestication was in the Yangtze basin of China, but a largely separate trajectory into rice cultivation can be traced in the Ganges plains of India. Intriguingly, contact-induced hybridisation is indicated for the early development of indica in northern India, ca. 2000 BC. An updated synthesis of the interwoven patterns of the spread of various rice varieties throughout Asia and to Madagascar can be suggested in which rice reached most of its historical range of important cultivation by the Iron Age.  相似文献   
23.
Neutron activation analysis has been used to characterize 60 metal objects from the Moche site, of which four are associated with the Chimú Period, two with the Early Chimú Period and the others with various Moche IV contexts. Different types of utilitarian and non‐utilitarian objects were analysed to identify the metals present, and to investigate their chemical composition and their eventual source. The results clearly indicate the distinction between Chimú and Moche artefacts and confirm the generalized opinion that arsenic bronze was popular after ad 900. They also indicate that gilding copper objects with gold was already a common practice during the Moche era.  相似文献   
24.
The origin of the Acheulean constitutes a key aspect of current research in the archaeology of human evolution. Olduvai Gorge is one of the main sites in Africa in the study of the transition from the Oldowan to the Acheulean, due to both the uniqueness of its archaeological record, and the influence of early investigations at Olduvai on the development of Early Stone Age research. This paper reviews the impact of work at Olduvai in shaping a modern view of cultural evolution from the Oldowan to the Acheulean. It also evaluates the lithic assemblages excavated by Mary Leakey in Olduvai Middle and Upper Bed II, based on a first-hand review of the collections. We conclude that previous paradigms used to explain inter-assemblage variability are not superseded as much as generally assumed, and that a modern view of the origins of the Acheulean requires a reassessment of the cultural, biological, and paleoecological evidence at Olduvai and elsewhere in Africa.  相似文献   
25.
26.
International Journal of Historical Archaeology - The location, size, and structure of the farmlands and hydraulic systems built by the Indigenous inhabitants of Gran Canaria, Canary Islands,...  相似文献   
27.
Vezzosi, R.I., June 2012. First record of Procariama simplex Rovereto, 1914 (Phorusrhacidae, Psilopterinae) in the Cerro Azul Formation (upper Miocene) of La Pampa Province; remarks on its anatomy, palaeogeography and chronological range. Alcheringa, 157–169. ISSN 0311-5518.

New records of Procariama simplex in central and northwestern Argentina are reported. The fossil material includes mandibular bones, cervical vertebrae and several elements of the fore and hindlimbs. After an exhaustive comparison of anatomical characters and morphometric analysis, the fossil specimens are assigned to the psilopterine Procariama simplex. The specimen from La Pampa Province represents the first record of a psilopterine in this central region of Argentina and derives from upper Miocene sediments of the Cerro Azul Formation. Lithological features and biostratigraphical data allow the host bed to be assigned to the Huayquerian faunal stage (late Miocene). The La Pampa record broadens the geographical distribution of Procariama simplex, which was previously restricted to northwestern Argentina.

Raúl Ignacio Vezzosi [vezzosiraul@gmail.com], Centro de Investigaciones Científicas y Transferencia de Tecnología a la Producción CICYTTP-CONICET, Materi y España s/n (3105), Diamante, Entre Ríos, Argentina. Received 1.4.2011, revised 28.5.2011, accepted 14.6.2011.  相似文献   
28.
Sphenophytes are a common floral element in the Triassic of Gondwana. Most sphenophyte compression fossils have been conventionally assigned to a few, presumably very widespread species of Neocalamites based on vegetative features of the stems (or pith casts) and the foliage. During recent decades, however, new reports on morphological and anatomical details of some of these fossils have cast doubt on the systematic affinities of many Gondwanan Triassic sphenophytes. Here we describe Neocalamites suberosus (Artabe & Zamuner) nov. comb. et emend. and Schizoneura africana Feistmantel emend. from several Triassic deposits in the central Transantarctic Mountains and Victoria Land, East Antarctica. The material enables a critical reevaluation of morphological and anatomical features that have been historically used to define the two genera, including leaf-base morphology, degree of leaf fusion, stem vasculature and vallecular canals, and features of the nodal diaphragm. The diagnoses of Neocalamites and Schizoneura are emended so that they more accurately reflect recent advances in our understanding of the anatomy and ontogeny of these plants.

[Benjamin Bomfleur [bbomfleur@ku]edu], Rudolph Serbet [serbet@ku.edu], Edith L. Taylor [etaylor@ku.edu] and Thomas N. Taylor [tntaylor@ku.edu], Department of Ecology and Evolutionary Biology, and Biodiversity Institute, University of Kansas, Lawrence, KS 66045, USA; Ignacio H. Escapa [iescapa@mef.org.ar], CONICET—Museo Paleontológico Egidio Feruglio, Trelew, Chubut 9100, Argentina. Received 4.7.2012; revised 22.12.2012; accepted 7.1.2013.

Bomfleur, B., Escapa, I.H., Serbet, R., Taylor, E.L. & Taylor, T.N., 2013. A reappraisal of Neocalamites and Schizoneura (fossil Equisetales) based on material from the Triassic of East Antarctica. Alcheringa 37, 1–17. ISSN 0311-5518.  相似文献   
29.
This article addresses the pickup problem , wherein patrons briefly interrupt their predetermined journeys to obtain a simple good, such as fast food or a video, and then resume their journeys. This is a problem from the class known as the flow-interception location problems. Traditional flow-interception location models (FILMs) are used to select service locations such that the intercepted flows are maximized. In these traditional models, only flow quantities are considered; these models do not consider where a pickup is made in a journey. However, in the real world, consumers often wish to obtain a product or service at or near a specific location along their trips. The pickup model (PUP) proposed here considers consumers' locational preferences, providing a much broader, more realistic approach than FILM (a special case of PUP) to problems in the private and public sectors. By considering which patrons are served where, PUP transforms the FILM into a flow-interception location-allocation model, providing a fruitful garden for further research. Geographic information systems and optimization engines are integrated to investigate the PUP model in real-world transportation systems. Reported findings demonstrate that the optimal locations identified by traditional models arise solely from network flow structure, whereas the optimal locations identified by PUP result from trade-offs between network flow structure and the importance of proximity to preferred locations. One important discovery is that PUP solutions are superior to those of traditional FILMs if consumers have locational preferences. Up-to-date, real-world transportation networks provide a realistic test-bed for this and other models of the flow-interception type.  相似文献   
30.
Innovation is increasingly supported by public authority action focused on regions and small and medium enterprises (SMEs). In this line, the region of Madrid launched a programme to create Technology Diffusion Centres (TDCs) in order to promote innovation culture among the SMEs of the region. This article analyses the nature of innovation activities in these firms, and the achievements of the TDCs through their work with them. Different types of TDCs are compared according to the approach they applied and the agent to which they were linked. Ten indicators were used to examine the degree of embeddedness and performance of the different TDCs among the SMEs. Results show that a sectoral approach in conjunction with links to business association is the best option for the TDCs in urban and industrial areas. However, in the peripheral or less favourable areas, such as rural ones, a territorial approach in conjunction with links to local entities is the most effective alternative.  相似文献   
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