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101.
The phenomenon of equifinality complicates behavioral interpretations of faunal assemblages from contexts in which Pleistocene hominins are suspected bone accumulators. Stone tool butchery marks on ungulate fossils are diagnostic of hominin activities, but debate continues over the higher-order implications of butchered bones for the foraging capabilities of hominins. Additionally, tooth marks imparted on bones by hominins overlap in morphology and dimensions with those created by some non-hominin carnivores, further confounding our view of early hominins as meat-eating hunters, scavengers or both. We report on the manual/oral peeling of cortical layers of ungulate ribs as taphonomically diagnostic of hominoid/hominin meat- and bone-eating behavior that indicates access to large herbivore carcasses by hominins at the site of BK, Olduvai. Supporting these inferences, we show that certain types of rib peeling damage are very rare or completely unknown in faunas created by modern carnivores and African porcupines, but common in faunas modified by the butchery and/or consumption activities of modern humans and chimpanzees, during which these hominoids often grasp ribs with their hands, and then used their teeth to peel strips of cortex from raggedly chewed ends of the ribs. Carnivores consume ungulate ribcage tissues soon after kills, so diagnostic traces of hominin butchery/consumption on ribs (i.e., peeling and butchery marks) indicate early access to ungulate carcasses by BK hominins. Tooth marks associated with the peeling and butchery marks are probably hominin-derived, and may indicate that it was not uncommon for our ancestors to use their teeth to strip meat from and to consume portions of ribs. Recognition of rib peeling as a diagnostic signature of hominoid/hominin behavior may also aid the search for pre-archaeological traces of hominin meat-eating.  相似文献   
102.
Site GNL Quintero 1 (GNLQ1), located on the central coast of Chile, is the only documented Late Pleistocene drowned terrestrial site along the Pacific Coast of South America. Faunal evidence at the site is varied, and so far, remains of the following taxa have been found: extinct Camelidae, Cervidae, Equidae, Mylodontidae, Xenarthra, but also Myocastoridae, Canidae and Octodontidae. Both geological and paleoenvironmental data indicate that GNLQ1 developed in a floodplain or low-energy environment during the Last Glacial Maximum (LGM). Prior to the post-glacial rising of the sea level, the site would have been located several kilometres inland as the paleoshoreline was farther out on the continental shelf. In accordance with this background, the present study addresses the analysis of the spatial distribution of the bone deposits of GNLQ1 by considering both scenarios, the terrestrial phase related to the formation and modification of the fossil assemblage prior to the transgression, and the marine phase, subsequent to inundation. Results indicate modifications related to low-energy flow environment and carnivore activity dominated during the terrestrial phase and the action of marine organisms during the marine phase. Other taphonomic modifications are not easily attributable to either one or the other environmental context.  相似文献   
103.
The Krafla geothermal system is located in Iceland's northeastern neovolcanic zone, within the Krafla central volcanic complex. Geothermal fluids are superheated steam closest to the magma heat source, two‐phase at higher depths, and sub‐boiling at the shallowest depths. Hydrogen isotope ratios of geothermal fluids range from ?87‰, equivalent to local meteoric water, to ?94‰. These fluids are enriched in 18O relative to the global meteoric line by +0.5–3.2‰. Calculated vapor fractions of the fluids are 0.0–0.5 wt% (~0–16% by volume) in the northwestern portion of the geothermal system and increase towards the southeast, up to 5.4 wt% (~57% by volume). Hydrothermal epidote sampled from 900 to 2500 m depth has δD values from ?127 to ?108‰, and δ18O from ?13.0 to ?9.6‰. Fluids in equilibrium with epidote have isotope compositions similar to those calculated for the vapor phase of two‐phase aquifer fluids. We interpret the large range in δDEPIDOTE and δ18OEPIDOTE across the system and within individual wells (up to 7‰ and 3.3‰, respectively) to result from variable mixing of shallow sub‐boiling groundwater with condensates of vapor rising from a deeper two‐phase reservoir. The data suggest that meteoric waters derived from a single source in the northwest are separated into the shallow sub‐boiling reservoir, and deeper two‐phase reservoir. Interaction between these reservoirs occurs by channelized vertical flow of vapor along fractures, and input of magmatic volatiles further alters fluid chemistry in some wells. Isotopic compositions of hydrothermal epidote reflect local equilibrium with fluids formed by mixtures of shallow water, deep vapor condensates, and magmatic volatiles, whose ionic strength is subsequently derived from dissolution of basalt host rock. This study illustrates the benefits of combining phase segregation effects in two‐phase systems during analysis of wellhead fluid data with stable isotope values of hydrous alteration minerals when evaluating the complex hydrogeology of volcano‐hosted geothermal systems.  相似文献   
104.
Patent Places: Size Matters   总被引:5,自引:0,他引:5  
In this paper I investigate the United States urban system of technical advance by analysis of metropolitan patent data. Residents of metropolitan areas obtain most of the patents awarded to Americans and the largest areas predominate, signifying that urbanization externalities facilitate invention. The advantages of large areas arise from lopsided concentrations of technologically intensive manufacturing and an uneven distribution of well-educated people. Location with respect to the traditional manufacturing belt also plays a role. Metropolitan residents in the manufacturing belt remain the most industrious inventors. The contribution of leading educational and research institutions to technical advance is manifest in small urban centers and outside the traditional manufacturing belt.  相似文献   
105.
The author seeks to analyse the repercussions and consequences of the Pinochet affair for Chilean domestic politics. He explains how the legacy of seventeen years of authoritarian rule has shaped the deep divisions within Chilean society regarding the prosecution of the Chilean former dictator in the London courts. Chile is an incomplete democracy and Pinochetism is very much alive in Chile today.
The author is very critical of the role played by the current Chilean government and political class, for their behaviour during the affair. In granting a special mission to the General which gave him immunity and later supported his legal case after initial hesitation, the government has shown confusion that has not advanced the case for full democratization and justice in Chile. The ambiguous behaviour of the political class during the episode has discredited its prestige in the eyes of public opinion. Chilean society, according to the author, has missed an opportunity to advance justice and the dignity of the country.  相似文献   
106.
Proximal radio‐ulnar synostosis (RUS) may occur congenitally, either as an isolated condition or as part of a syndrome, or it may occur as a secondary complication of forearm trauma. We provide a key for the differential diagnosis of congenital versus traumatic RUS, and for differentiation between types of congenital RUS. Congenital cases (CRUS) include absence of fracture, radial head abnormalities, radial shaft bowing, and absence of a sigmoid notch, whereas post‐traumatic RUS results from either radial neck fracture or evulsion of the biceps brachii, followed by ossification of the resulting haematoma or of the interosseous (IO) membrane. Congenital cases include those which result from incompetent differentiation of the single mesenchymal mass that gives rise to the radius and ulna (Type I) and those that result from radial head dislocation in utero, resulting usually from humeral or ulnar defects (Type II). Type II CRUS can be differentiated by the presence of radial overgrowth, among other factors. Following these guidelines, we describe and compare the morphology of three congenital cases from North America. Two present bony fusions and one a functional fusion with radial overgrowth. In each case, CRUS significantly limits both supination and pronation. Despite differences among the cases, several morphological accommodations are shared as a result of fixation in the neutral (semi‐pronated) position. These changes include the ventral migration of the IO crests of the ulnae and enlargement of the dorsal tubercles of the radius. Understanding the pattern of accommodations made in the face of compromised function ultimately increases our understanding of the patterns of growth in normal functional regimes. Copyright © 2000 John Wiley & Sons, Ltd.  相似文献   
107.
108.
The behavioural, cultural, and political implications of archaeological human remains in non‐mortuary, possibly culinary, contexts requires that we understand the range of mortuary practices in a particular region. Although several rockshelter sites on Mangaia, Cook Islands have yielded burned, fragmentary human bones in earth ovens that seem to support archaeological models and ethnohistoric accounts of ritual sacrifice and cannibalism, the absence of data on the range of Mangaian mortuary patterns obscures these interpretations. We describe burial patterns based on 40 above‐ground interments representing at least 92 individuals in caves of Mangaia, Cook Islands, in order to begin to develop an island‐wide perspective on mortuary patterns. Sampling both pre‐ and post‐European contact sites we found that multiple interments dominate probable pre‐contact burials (73%, 19 of 26) and single interments dominate post‐contact contexts (80%, eight of ten burials), probably reflecting the influence of Christianity on mortuary ritual. Subadults were more frequent in all post‐contact contexts suggesting alternative burial places, probably church cemeteries, for adults. Burial cave remains are broadly consistent with ethnohistoric accounts of interment in caves, however, they also illustrate additional burial practices and differences between time periods, such as primary body position and the role of multiple‐individual interments, which are not discussed ethnohistorically. The mortuary practices in Mangaian burial caves differ from burials associated with marae and seem completely unrelated to the presence of highly fragmentary and burnt human remains in pre‐contact rockshelter middens elsewhere on the island. Copyright © 2003 John Wiley & Sons, Ltd.  相似文献   
109.
lydia n. yu  jose 《外交史》2005,29(2):343-347
Book reviewed:
Julian Go and Anne L. Foster, eds. The American Colonial State in the Philippines, Global Perspectives . Durham, NC and London: Duke University Press, 2003. 312 pp. Index. $79.95 (cloth), $22.95 (paper).  相似文献   
110.
ABSTRACT This paper surveys recent evidence on the determinants of (national and/or foreign) industrial location. We find that the basic analytical framework has remained essentially unaltered since the early contributions of the early 1980s while, in contrast, there have been advances in the quality of the data (more firm and plant level information, geographical disaggregation, panel structure, etc.) and, to a lesser extent, the econometric modeling. We also identify certain determinants (neoclassical and institutional factors) that tend to provide largely consistent results across the reviewed studies. In light of this evidence, we finally suggest future lines of research.  相似文献   
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