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1.
Lead isotopic compositions of 12 galenas from five late Archaic-initial Woodland grave and habitation sites in southern Ontario have made it possible to determine the "most likely" source areas for the galenas. For one of the oldest sites (Finlan), the most likely source is in the southwestern Upper Mississippi Valley (Wisconsin-Illinois-Iowa) mineral district. The seven Finlan galenas exhibit a range of isotopic ratios; three of the largest specimens have substantial isotopic variations (up to 1.8 percent in the ratio of lead-207 to lead-206) on a scale of a few centimeters. This suggests that the lead isotopic zoning ascribed to the Upper Mississippi Valley area is not sufficiently well defined to enable us to determine if all the Finlan samples were derived from a single mineral deposit. Galenas from the other sites (Constance Bay, Hind, Bruce Boyd, and Picton) most probably originated in the southeastern Ontario-northwestern New York area. Isotopic differences among the Constance Bay, Hind, and Bruce Boyd galenas, on the one hand, and the Picton galena, on the other, suggest that at least two distinct sources in that region were exploited.  相似文献   

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Approximately 50,000 carbonized fruits of the species Chenopodium berlandieri recovered from Russell Cave, Alabama, and dating to 1975 +/- 55 before the present, exhibit a set of interrelated morphological characteristics reflecting domestication (thin testa, truncate margin, rectanguloid fruit cross section, ligulate cotyledons, and increased internal fruit volume). These morphological characteristics establish the presence of a domestic variety of Chenopodium in the eastern United States by 2000 years ago.  相似文献   

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Recent archeological fieldwork on the north coast of Peru permits a preliminary reconstruction of a prill-extraction copper and copper alloy smelting process heretofore undocumented in the New World. The process was applied on a large scale during the late pre-Hispanic period. This study provides strong support for the claim that central Andean metallurgy constituted one of the major independent metallurgical traditions of the world.  相似文献   

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Accelerator mass spectrometer dating of an assemblage of fibrous and leather footwear from Arnold Research Cave in central Missouri documents a long sequence of shoe construction by prehistoric Midwestern peoples, beginning perhaps as early as 8300 calendar years before the present (cal years B.P.). An earlier fibrous sandal form dates from 8325 to 7675 cal years B.P., and later fibrous or leather slip-ons span the period from 5575 to 1070 cal years B.P. The assemblage adds to a growing picture of the highly varied nature of prehistoric footwear production in the United States throughout the Holocene.  相似文献   

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Archeological materials from 8.5 meters of deposits in a stratified rock shelter in the Absaroka Mountains near Yellowstone National Park provide a projectile point sequence and cultutral record beginning more than 9000 years ago, and include evidence of human occupation durnig the Altithermal period.  相似文献   

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The earliest pottery yet found in the Western Hemisphere has been excavated from a prehistoric shell midden near Santarém in the lower Amazon, Brazil. Calibrated accelerator radiocarbon dates on charcoal, shell, and pottery and a thermoluminescence date on pottery from the site fall from about 8000 to 7000 years before the present. The early fishing village is part of a long prehistoric trajectory that contradicts theories that resource poverty limited cultural evolution in the tropics.  相似文献   

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A cave in Guerrero, Mexico, investigated in 1968, contained previously unreported Olmec paintings. These paintings, some of the oldest known in Mesoamerica, are stylistically similar to Olmec art from the site of LaVenta, on Mexico's Gulf Coast, but contain several important glyphic motifs never previously known to have existed at this time level. The iconography of the paintings confirms several important hypotheses concerning basic concepts of Olmec religion; the cave itself was probably a shrine to water and fertility. Several pre-Hispanic textile fragments found in the cave are probably from a later culture period.  相似文献   

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Hill WE  Neuman RW 《Science (New York, N.Y.)》1966,154(3753):1171-1173
Thirteen archeological specimens were analyzed spectrographlically, and within defined limits they were determined to be native copper. Twelve of the specimens show close elemental homogeneity and are believed to be of Lake Superior ore; the origin of the other specimen is deviolus.  相似文献   

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The patterning found in certain wetlands of lowland Mesoamerica has added an important element to the subsistence system that may be attributed to pre-Hispanic inhabitants of the region. The form of the remains, largely expressed in terms of surface vegetation, suggests agriculture on planting platforms, separated by canals. The physical and chemical aspects of the stratigraphy have clarified depositional environments but have not indicated agricultural horizons. Maize phytoliths at about 1 meter below the surface in two Central Veracruzan wetlands do confirm the practice of agriculture. Associated ceramics indicate wetlands agriculture was practiced by A.D. 500 and perhaps earlier.  相似文献   

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采用超声波辅助酶法提取霍山石斛中的生物碱,通过对固液比、超声时间、超声功率、酶解时间、复合酶(纤维素酶和果胶酶1∶1等活力混合)质量分数的单因素试验和正交试验,确定提取最佳的条件;通过气相色谱-质谱法对霍山石斛中生物碱的组成成分进行分析;通过傅里叶变换红外光谱及二阶导数变换谱图快速鉴定霍山石斛和铁皮石斛。结果表明,当固液比为1:40(g·mL-1),超声时间为20 min,超声波功率为200 W,复合酶(纤维素酶和果胶酶1∶1等活力混合)添加量1.5%,酶解时间1.5 h为提取条件时,提取效率最佳,生物碱得率为0.053%。根据气相色谱-质谱法检测结果可得知,相对于铁皮石斛,霍山石斛的石斛碱和6-羟基石斛次碱为其特殊生物碱。二阶导数变换谱图可更直观地通过二者峰形状、个数和强度的不同来区分。因此,可以将气相色谱质谱联用和傅里叶红外光谱结合在一起来高效鉴定霍山石斛与铁皮石斛。  相似文献   

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A fourth specimen of Archaeopteryx (cf. lithographica), the oldest known fossil bird, was recently found in the collections of the Teyler Museum in the Netherlands. Unique preservation of the horny sheaths of the manus claws provides new evidence that may be relevant to the question of the origins of avian flight. Tentative interpretation suggests a cursorial rather than arboreal origin.  相似文献   

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A vampire bat, Desmodus rotundus, captured in Oaxaca, Mexico, in August 1970, was found to be infected with the epidemic strain of Venezuelan equine encephalomyelitis virus at the same time that an equine epizootic was occurring there.  相似文献   

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The discovery of butchered and modified bones of extinct Pleistocene fauna from Old Crow Flats, Yukon Territory, and the Dutton and Selby sites, Colorado, provides some of the earliest evidence for man in the New World. However, the significance of these discoveries rests entirely on the ability to determine whether these remains were modified by man. The results of experiments of elephant butchering, bone fracturing, and bone tool manufacturing support the hypothesis that these modified bones can be used to identify the presence of cultural activities.  相似文献   

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Tetrahydropapaveroline is a benzyltetrahydroisoquinoline alkaloidderivative of the biogenic amine, dopnmine. Alcohol, by way of its primary metabolite, acetaldehyde, competitively inhibits nicotinamide-adenine Sinucleotide-linked aldehyde dehydrogenase and augments the formation of tetrahydropapaveroline in vitro. The limited capacity of brain to oxidize aldehydes may be of pharmacological importance because it facilitates the production of tetrahydropapaveroline in the presence of drugs which inhibit this enzyme.  相似文献   

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