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21.
Joseph A. Rodriguez 《对极》1999,31(2):212-228
Regional transportation planning shaped minority activism in the mid-1960s. The Bay Area Rapid Transit (BART) system encouraged West Oakland activists to create a strong local identity. BART supporters valued regional mobility and blamed ghetto poverty on the inaccessibility of suburban jobs. Minority activists blamed BART for harming the ghetto poor by encouraging job migration to the suburbs, and for displacing residents. As compensation, they demanded that BART hire minority workers and increase relocation payments. While West Oakland activists largely failed to influence BART, the newly unified community did gain local control of schools and urban poverty programs. 相似文献
22.
Martín Horacio Fugassa María Ornela Beltrame Norma Haydée Sardella María Teresa Civalero Carlos Aschero 《Journal of archaeological science》2010
Coprolites attributable to humans, dated from the Pleistocene–Holocene transition, obtained from the archaeological site Cerro Casa de Piedra, Santa Cruz Province, were examined for parasites. The feces were processed by rehydration and spontaneous sedimentation using conventional parasitic procedures. Helminthic eggs recovered were identified as Trichuris sp., Calodium sp., other capilariids, and ancylostomid (Nematoda), probably Hymenolepis sp. and anoplocephalid (Cestoda); one oocyst attributable to Eimeria macusaniensis (Apicomplexa) was also found. According to the life-cycles and specificity of the parasites found, it is possible to suggest that some species (i.e., E. macusaniensis and Calodium sp.) represent parasites in transit or pseudoparasitism. Paleoparasitological results revealed the existence of an intensive relationship between parasites and humans in the Pleistocene–Holocene transition in Patagonia. Evidence suggests an early association among parasites, rock shelters and hunter–gatherers in the region. It is also postulated that the ancient lifestyles associated with caves and rock shelters were conductive to illness. 相似文献
23.
Paola Villa Maria Fernanda Sánchez Goñi Gloria Cuenca Bescós Rainer Grün Aurelie Ajas Juan Carlos García Pimienta Wendy Lees 《Journal of archaeological science》2010
Data of high resolution for reconstructions of archaeological site formation processes can be obtained only by the use of precise excavation methods and comprehensive recovery techniques using fine-mesh water screening, followed by meticulous sorting and quantitative studies of all the small organic components from the screens. These methods are generally used at human occupation sites, but are not often employed at paleontological or mixed human-carnivore sites. At the site of Bois Roche, an Upper Pleistocene hyena den, we have used these meticulous recovery techniques in combination with absolute dating, geoarchaeological observations, taphonomic analyses, studies of microvertebrates and pollen analysis. Correlation of the site environmental data from pollen and microvertebrate assemblages with the vegetation record of a deep-sea core taken in the Bay of Biscay have allowed us to constrain the ages provided by ESR dating of bovid teeth and to reconstruct the physical environment of the site with a degree of confidence rarely achieved by the use of fossil remains from archaeological sites alone. 相似文献
24.
This article explores the relevance of acoustics as a factor for in the production and active use of Levantine rock art in Spain. The renowned rock art area of La Valltorta Gorge serves as a case study. Two experiments are described; the first assessed whether the sites with the most painted motifs had better acoustics than those with fewer motifs. The second tested which areas in La Valltorta Gorge had better acoustics and whether there was a difference between the acoustics of the decorated area and the contiguous sectors of the Gorge where no paintings have been found. In both experiments different sounds and pitches were used. The results suggest a strong relationship between the painted areas and the sonority of the place, with the major sites generally having provided the best results, with the exception of the sonority when facing the rock art panels. It is suggested that La Valltorta Gorge was chosen to be decorated with a view to increasing the perceptual impact of the rituals that may have been held at rock art sites due to the amplification caused by the echoing and resonance. 相似文献
25.
Pedro Bosch Inmaculada Alemán Carlos Moreno-Castilla Miguel Botella 《Journal of archaeological science》2011
Bones treated at low temperature do not present major modifications although, macroscopically, boiled bones may be distinguished from unboiled ones as they are smoother, lighter and more transparent. Such observations should correspond to textural modifications at a nanometric level and should depend on boiling time. In this study, contemporary human bones, boiled during various time intervals, were characterized using scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD) and nitrogen adsorption (BET). The results were used to estimate the boiling time in four archaeological samples (Neolithic bones from Malalmuerzo cave, Spain). It is concluded, comparing Neolithic bones to contemporary ones and from the textural characterization at a nanometrical level, that two of the archaeological bones were boiled and that they were boiled for less than 6 hours. 相似文献
26.
Carlos Argáez Erasmo Batta Josefina Mansilla Carmen Pijoan Pedro Bosch 《Journal of archaeological science》2011
The study of black patches and spots in prehispanic bones of Tlatelolco and Tlapacoya is presented. The chosen characterization techniques, X-ray Fluorescence, X-ray Diffraction, Scanning Electron Microscopy, Energy Dispersive X-ray Spectroscopy, Infrared Spectroscopy and Gas Chromatography are complementary and they all conclude that the bone black pigment is constituted, mainly, by amorphous carbon and some mineral inclusions. Gas Chromatography and Infrared Spectroscopy show that the pigment is constituted by organic compounds as aromatic hydrocarbons, mainly bitumen. An explanation on how the spots were formed is proposed. 相似文献
27.
This article proposes a damage index for the seismic analysis of Reinforced Concrete members using the hysteretic energy dissipated by a structural member and a drift ratio related to failure in the structure. The index was calibrated against observed damage in laboratory tests of 76 RC column units under various protocols. Values obtained in this calibration had acceptable agreement with the levels of damage observed in the test specimens. An analysis of the parameters involved in the definition of the proposed damage index shows the importance of displacement history in the drift ratio capacity of structures. 相似文献
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29.
Carlos Rivera 《Romance Quarterly》2013,60(3):127-134
30.
José Carlos Sánchez Pardo 《Early Medieval Europe》2013,21(2):140-168
This paper aims to bring together hitherto neglected archaeological data about the early medieval landscapes of Galicia (north‐west Spain), in order to understand the social transformations this ‘peripheral’ region underwent between the fifth and the ninth centuries and to frame them in the context of wider European debates. Despite its many limitations, the archaeology reveals that until the middle of the seventh century, the late antique society of Gallaecia experienced a previously unsuspected vitality. At this point a socio‐political fragmentation occurred, which was characterized by the strengthening of local power, until a further change took place with the progressive incorporation of Galicia into the Asturian kingdom in the ninth century. 相似文献