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11.
Sagasti, A.J., García Massini, J., Escapa, I.H., Guido, D.M. & Channing, A., August 2016. Millerocaulis zamunerae sp. nov. (Osmundaceae) from Jurassic geothermally influenced wetland environments of Patagonia, Argentina. Alcheringa 40, xxx–xxx. ISSN 0311-5518

A new species of Millerocaulis Erasmus ex. Tidwell emend. Vera is defined based on several permineralized stems recovered from geothermally influenced chert deposits in the Middle–Late Jurassic La Matilde Formation (Santa Cruz, Argentina). Millerocaulis zamunerae sp. nov. is characterized by the presence of an ectophloic dictyoxylic siphonostele, inner parenchymatic and outer sclerotic cortices, homogeneous sclerotic ring in the petiole bases, two masses of sclerenchyma lining the concavity of the petiolar vascular bundle, petiolar inner cortex with sclerenchyma strands in the outermost petiole cycles and stipular wings having one large and several smaller sclerenchyma bundles. Millerocaulis zamunerae inhabited geothermal wetlands and other hot-spring-related sedimentary facies associated with the La Bajada epithermal deposit. Reference to active geothermal wetlands, analogous living plants and other fossil hot spring ecosystems suggest the plant’s tolerance of physico-chemical stressors including elevated temperature, pH, salinity and phytotoxic metals/metalloids. Millerocaulis zamunerae thrived in wetlands preserved in the Jurassic geothermal systems of Santa Cruz Province, the same kind of environment in which Equisetum thermale Channing et al. was recorded previously.

Ana Julia Sagasti [] División Paleobotánica, Facultad de Ciencias Naturales y Museo. Becaria Doctoral Consejo Nacional de Investigaciones Científicas y Técnicas, Paseo del Bosque S/N B1900FWA La Plata, Buenos Aires, Argentina. Juan García Massini [] Centro Regional de Investigaciones Científicas y Transferencia Tecnológica de La Rioja (CRILAR), Provincia de La Rioja, UNLaR, SEGEMAR, UNCa, CONICET. Entre Ríos y Mendoza S/N, 5301 Anillaco, La Rioja Argentina. Ignacio H. Escapa [] Museo Paleontológico Egidio Feruglio, Consejo Nacional de Investigaciones Científicas y Técnicas, Av. Fontana 140, U9100GYO, Trelew, Chubut, Argentina. Diego M. Guido [] Instituto de Recursos Minerales (INREMI), Facultad de Ciencias Naturales y Museo, Universidad Nacional de La Plata. Consejo Nacional de Investigaciones Científicas y Técnicas. Calle 64 y 120, La Plata (1900), Argentina. Alan Channing [] School of Earth & Ocean Sciences, Cardiff University, Cardiff CF10 3AT, UK.  相似文献   
12.
ABSTRACT

Reinforced concrete structures came to Spain in the late-19th century, somewhat after the development of this new construction material elsewhere in Europe. Their introduction was pioneered in industrialized areas, especially Northern Spain, under systems first patented in other European countries. Local constructors built structures under patents with little or no explanations to account for calculation, design, and construction technique. Some of these buildings from the recent past are now listed buildings. This study centres on three construction projects under patented systems: Our Lady of “La Antigua”, Orduña (Monier system), “La Ceres” flour mill, Bilbao (Hennebique system), and Alhóndiga, Bilbao (Blanc system). Preliminary structural studies analyzed morphology, reinforcements, concrete strength and pathological processes in each structure. Their results are compared with information taken from the patent systems in use at the time. This useful information on the structures, which may be expanded in future research, clearly describes the relationship between patent specifications and reality.  相似文献   
13.
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   
14.
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   
15.
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   
16.
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   
17.
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   
18.
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   
19.
The extraction of silver has traditionally been considered as one of the main incentives for the Phoenician expansion throughout the Mediterranean and their settlement in Iberia. In this paper, we approach the organization of silver production in Iberia during the Early Iron Age through the study of the evidence of production currently available and the development of Lead Isotope Analysis (LIA). Previous results (Hunt 2003; Stos Gale 2001; Kassianidou 1992) are considered in the light of new data. The extraction of silver from complex minerals noticeably intensifies in south‐west Iberia. Imports of exogenous lead, needed for the extraction of silver from these complex minerals, are evident. Supplies of lead come in from other regions of Iberia, such as Gádor, Cartagena/Mazarrón, Linares or even the mining district of Molar‐Belmunt‐Falset (MBF) in Catalonia. This picture reveals that the organization of silver production was much more complex than initially thought, with the articulation of an exchange network of raw materials at a macro‐territorial scale embracing almost all Iberia. The socioeconomic implications that control of these networks of lead distribution could have had are also discussed.  相似文献   
20.
The role of natural processes in the formation of the Bed I and II sites at Olduvai Gorge (Tanzania) remains the subject of much debate, five decades after their original excavation. Preferred orientation of items is indicative of water disturbance, but compass bearings were not available in Mary Leakey's (1971) study. Using GIS methods, we have vectorized maps from 1960s excavations at Olduvai, and applied a range of statistical techniques to calculate items strike. The GIS analysis suggests strongly preferred orientation patterns in Bed I, and more heterogeneous angular histograms in Bed II. Two complementary lines of evidence support these results. Firstly, modelling of potential mapping errors provides a large interval of confidence for preferred orientation patterns. Second, the GIS study was extended to photographs of the earlier excavations and to maps from recent fieldwork at Olduvai; both yielded patterned arrangement of lithics and bones, and are consistent with results based on the analysis of the 1960s maps, i.e. a large number of the Bed I and II assemblages are preferentially oriented. These results highlight the potential of GIS applications to the analysis of imagery in Stone Age studies, and bear important implications for the understanding of the role of natural agents in site formation processes at Olduvai.  相似文献   
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