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51.
Planning,Sustainability and Airport-Led Urban Development 总被引:1,自引:0,他引:1
Robert Freestone 《International Planning Studies》2009,14(2):161-176
Airports are no longer places where planes just take off and land but have evolved into major business enterprises with spatial impacts and functional implications that extend deep into metropolitan areas. They are vital hubs in the global space of flows. Airport-led urban development, notwithstanding its employment and income generating capabilities and potentials, comes with costs and risks: economic, environmental, and cultural. A host of planning issues are raised. Traditional NIMBY reactions against airport expansion are evolving into more fundamental critiques of aviation around issues such as climate change. Mediating the conflict between the aviation industry's pro-growth stance and more sceptical perspectives is the concept of sustainable aviation. This may prove an oxymoron but it remains vital to link airport planning to the broader planning of sustainable communities and regions. 相似文献
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Modification of chemical and magnetic extraction techniques has yielded biogenic magnetite/maghemite from human hippocampal tissue. Particles were identified using high resolution transmission electron microscopy, electron diffraction and elemental analysis. Though its presence has been inferred from magnetic analyses, this is the first direct observation of magnetic biominerals from the hippocampus. 相似文献
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L Liberman N Bracero MA Vuolo DD Dershaw EA Morris AF Abramson PP Rosen 《Canadian Metallurgical Quarterly》1999,172(2):331-337
Neisseria meningitidis, Haemophilus influenzae, and Streptococcus pneumoniae possess the ability to cleave human IgA1 antibodies, and all successfully colonize and occasionally invade the human upper respiratory tract. N. meningitidis invades the bloodstream after a period of nasopharyngeal colonization. We directly compared levels of IgA1 protease activity in strains (n=52) derived from the cerebrospinal fluid or blood of patients with meningococcal disease with strains of N. meningitidis obtained from asymptomatic carriers (n=25). IgA1 protease activity was determined by a sensitive semiquantitative ELISA assay. Levels of IgA1 protease activity were significantly higher (P<0.0001) in strains associated with invasive meningococcal disease (98% with detectable activity, mean = 580 mU) than with those obtained from asymptomatic carriers (76% with detectable activity, mean = 280 mU). Despite marked variation in enzyme activity, almost all strains (96%) possessed the gene for IgA1 protease. Given the panmictic population structure of the bacterial isolates investigated, these data, obtained from two groups infected with N. meningitidis, but with markedly different clinical outcomes, provide the first quantitative evidence that IgA1 protease activity is a virulence determinant that contributes to the pathogenic phenotype, and suggest IgA1 protease as a potential target for prophylaxis. 相似文献
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AA Sosunov PP Krugliakov VN SHvalev G Guski IuV Postnov 《Canadian Metallurgical Quarterly》1997,59(2):32-37
Debridement of nonviable tissue is crucial to optimal wound healing, which can be impaired unless all necrotic tissue, exudate, and metabolic wastes have been removed from the wound. Debridement methods are classified as sharp, mechanical, chemical, and autolytic. This article describes methods of debridement and their outcomes. 相似文献
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Twenty-three well-conditioned ponies were evaluated for insulin and glucose response following oral glucose administration (1 g/kg bodyweight [bwt] as a 20 per cent solution). Ponies were defined as normal if total insulin secretion (TIS) was less than 149 mu iu/ml h and the glucose concentration was below 11.1 +/- 0.11 mmol/litre (200 +/- 2 mg/dl) at all times following oral glucose administration. When glucose concentrations were maintained below 11.1 +/- 0.11 mmol/litre, the area under the glucose curve (TG) was less than 17.4 mmol/litre/h (314 mg/dl/h). The ponies were assigned to four groups based on insulin and glucose response: Group 1 (n = 7), normal; Group 2 (n = 5), high insulin, normal glucose; Group 3 (n = 8), high insulin, high glucose and Group 4 (n = 3), high glucose, normal insulin. This classification is an initial attempt to define normal insulin and glucose response in ponies. Additional data need to be accumulated to define further insulin resistance and diabetes in ponies. 相似文献