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91.
I summarize recent archaeological work in Oaxaca, Mexico, with a focus on questions central to world prehistory: the origin and collapse of complex societies. Monte Albán was the capital of an emerging civilization in the southern highlands of Mexico during the second half of the first millennium B.C. Soon after the foundation of the ancient city, there is evidence for state formation and a political expansion into regions outside the Valley of Oaxaca. Centuries later, Monte Albán went into decline, giving way to the competing small polities found throughout Oaxaca at the time of the Spanish conquest. Since the late 1960s, our knowledge of these changes has been transformed by study of Oaxaca's pre–Monte Albán past, regional settlement surveys, and processual model building. Evolutionary and historical perspectives allow for significant refinement of current debates surrounding the rise and fall of complex societies in Oaxaca.  相似文献   
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The Early Historic Period in the Mun Valley occupies a critical three centuries, from A.D. 500 to A.D. 800, a period often known as that of Zhenla, a name derived from early Chinese accounts. This article first describes early findings of fieldwork designed to illuminate the prehistory of the upper Mun Valley, a period which covers approximately two millennia, with initial settlement now dated between 1500 and 1000 B.C. It then considers the nature of the transition to the complex polities of Zhenla. This involves a combination of archaeological and documentary evidence. Sources for the latter are rare for the Mun Valley, but by broadening the area considered, it is possible to integrate archaeological and historical sources in order to portray the intensifying social changes which characterize the Early Historic Period. It is suggested that most of the Mun Valley was occupied by Khmer speakers during the Iron Age, people responsible for the transition to increasingly centralized polities of the Early Historic Period. In the upper reaches of the Mun catchment, and in the Chi Valley to the north, the late prehistoric inhabitants spoke Mon. They had close affinities with the Dvaravati polities of Central Thailand. If confirmed, this hypothesis would indicate a series of local trends towards increasing social complexity which we can recognize in the early epigraphic record.  相似文献   
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Cultural resource management (CRM) work accounts for most of the archaeology conducted in the United States. A diverse and somewhat fragmented field, CRM has nonetheless achieved a degree of institutional and organizational maturity. CRM archaeology has produced important contributions to archaeological methodology and has established and refined knowledge of regional cultural-historical sequences and settlement and subsistence patterns. The current florescence of historical archaeology is attributable to CRM. Yet the maintenance of high quality in CRM is a pervasive and enduring problem. Academic institutions need to reestablish alliances with the CRM community. The future viability of CRM archaeology depends on factors both internal and external to the discipline: regulatory and statutory “reform,” agency funding levels, looting and other destructive forces, and Native American and other public involvement.  相似文献   
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Charles Edouard Brown-Séquard used observation of recovered patients and experimental animals to support his theory of cerebral localization. Recovery theories assume that the nervous system is composed of one organ or many, and that each organ has one function or many. From his own studies as well as others, Brown-Séquard concluded that the brain contained at least nine separate organs, each with a single distinct function, and that each organ is organized, not as a geographically isolated cluster of neurons, but as a widely disseminated network. According to his view, function is not uniformly distributed in an organ. Focal necrosis of part of an organ temporarily inhibits the action of distant, undamaged parts; resolution of this inhibition results in recovery. Using this theory of cerebral localization and recovery, Brown-Séquard practiced an early form of scientific neurology.  相似文献   
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Neurology in its modern sense was first studied in the well-known neurological institutions of France and England. In America, however, this new field of medicine was developed by a physician in a private practice, Dr. William Alexander Hammond. This article addresses the question how Hammond was able to limit his practice to neurology. It is argued that Hammond was a famous military physician before becoming the first practitioner of clinical neurology in America. This fame translated into a large referral base.  相似文献   
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This address is concerned with the lack of detailed understanding we have of rivers. It is argued that to manage river systems for environ- mental and ecological sustainability, there must be understanding of riverine biophysical processes. These are explored through a consideration of: (1) channel airspace and water; (2) the perimeter conditions of the channel as the boundary between erosional channel and depositional floodplain, both of which occupy the valley-floor trough; (3) ecological components of channels and (4) the human components where human interactions with catchment environments have such impacts on the biophysical systems. Finally, the implications of these four components for understanding the systems for more sustainable management are discussed.  相似文献   
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