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991.
Tarek Ben Hassen Juan‐Luis Klein Diane‐Gabrielle Tremblay 《The Canadian geographer》2011,55(4):439-456
This article analyzes the mechanisms through which metropolitan governance is established in Montreal's aeronautics sector, one of the most important and innovative industries in the region. The article also examines the role of lead firms, socio‐economic actors, and public agencies from a territorial point of view. It is established that on the one hand the existence of a small number of prime producers at the local level facilitates productive linkages among businesses through subcontracting, and on the other hand, the intensive participation of intermediate socio‐economic agencies and organizations ensures a metropolitan anchoring of the sector and creates a strong territorial identity among the players. 相似文献
992.
John E. Martin 《The Canadian geographer》2011,55(4):457-469
Wetlands are common in Coastal Western Hemlock forests yet the hydrologic processes that generate runoff from small swamps are not completely understood. Direct field observations, hydrologic, and electrical conductivity data were collected from a gently sloping forested swamp complex from July to November 2009. Swamps occupied depressions between raised mounds (0.1 to 3 m high) and were connected by an ephemeral creek. Runoff was controlled by antecedent moisture conditions and influenced by basin microtopography. Two hydrologic regimes occurred during the study period and different runoff processes dominated each regime. Runoff was generated by subsurface flow during dry antecedent conditions as swamps remained hydrologically disconnected from each other. Runoff was generated by surface outflow from hydrologically connected swamps during wet antecedent conditions as ponded water spilled out of the depressions. The forested swamp complex produced a faster but limited hydrologic response during dry antecedent conditions compared to a slower but greater hydrologic response during wet antecedent conditions. Stormwater runoff and runoff ratios were up to two orders of magnitude higher in wet conditions than during similarly sized events in dry conditions. These factors should be considered when designing monitoring programs or runoff models in forested swamps with significant microtopography. Field surveys and estimates of hydrologic inputs and outputs may be useful in predicting the potential hydrologic connectivity of isolated forested swamps. 相似文献
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Panourias IG Stranjalis G Stavrinou LC Sakas DE 《Journal of the history of the neurosciences》2011,20(3):177-187
Numerous Hellenic terms have been gradually adopted during the development of modern medical science. Moreover, there are a significant number of words that derive directly from the Hippocratic texts. Hippocrates (ca. 460-ca. 377 BC), revered as the father of medicine, and his followers left behind a valuable heritage of medical knowledge that, practically, laid the foundations of Western medicine. Their theories, collected in Corpus Hippocraticum, transformed medicine by adding, mainly, clinical observation and inductive reasoning as significant parts of medical diagnosis and treatment. Additionally, Hippocratic writings have provided an invaluable heritage of medical terms for all medical fields. The present article examines the Hellenic and Hippocratic terminology referring to the spine and how this vocabulary has influenced and dominated upon modern spinal onomatology. 相似文献
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Nataliya E. Zaretskaya Nataliya V. Shevchenko Alexandra N. Simakova Leopold D. Sulerzhitsky 《Geochronometria》2011,38(2):116-127
In this paper, a detailed overview of the Holocene evolution of the North Dvina river (ND) delta (southern White Sea) is presented; it is based on radiocarbon dating, geomorphological and other field surveys, and plant macrofossil and palynological data. We have identified three main stages of the delta evolution: estuary erosional (Allerød — 5700 cal BC), lagoon or tidal-marsh (5700 cal BC — 3700 cal BC) and fan-delta accumulative (3700 cal BC — present). These stages are correlated with local climatic curves, sea level changes, glacioisostatic raise curve and Baltic Sea stages. A variety of landforms has been identified and dated within the delta. These results help to explain the spatial and temporal patterns in the prehistoric human occupation of this area. 相似文献
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Krysta Ryzewski Brian W. Sheldon Susan E. Alcock Max Mankin Sugeetha Vasudevan Nicholas Sinnott-Armstrong 《Archaeological and Anthropological Sciences》2011,3(2):173-184
This object-specific case study focuses on cupreous artifacts excavated from the Great Temple complex of Petra, Jordan to
demonstrate how the use of compositional X-ray analyses alongside two experimental applications (ImageJ software and nanoindentation)
have the potential to generate different and otherwise unobtainable information about archaeological metals. The study highlights
the value of using multiple techniques as a means of resolving the ambiguities that tend to arise from interpretations of
single-sited measurements on objects and from single-instrumental analyses during studies of production processes and consequent
material performance. Employing different techniques on multiple localities within a sample permits the gathering of precise
information about the behavior of and interrelationships between variables that affect the objects’ fabrication and use, particularly
composition, structure, and hardness properties. The resulting data are interpreted in association with contextual archaeological
information from Petra to consider the use-life and potential significance of these objects. 相似文献
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