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181.
Low-temperature (at T < 900–950 K) ignition delays of hydrogen–air mixtures are mainly measured in rapid compression machines (RCM). This communication is aimed at numerical simulation of ignition delays of hydrogen–air mixtures in the RCM by means of a coupled three-dimensional (3D) Unsteady Reynolds-Averaged Navier–Stokes (URANS) – Particle Method (PM) simulation of RCM operation capable of catching turbulence–chemistry interaction. The study indicates that the time history of piston motion in an RCM affects the final state of a test mixture at the end of compression stroke and therefore influences the phenomena relevant to test mixture ignition. More specifically, the calculations show that different laws of piston motion at a fixed average piston velocity (i.e., fixed piston displacement and fixed compression time) and fixed compression ratio result in different evolution of mean pressure, temperature and velocity fields in the RCM test section leading to different ignition behavior. The reasons for the arising differences lie in the fact that the local instantaneous piston velocity determines the roll-up vortex structure, strength and turbulence dissipation in it, heat transfer in test-section walls, and mass leakage through piston rings.  相似文献   
182.

Social scientists have described Japan's urban anti-pollution protests in the 1960s as a national phenomenon. However, in Kitakyushu, Japan's most polluted industrial city at that time, no distinct citizens' movement developed. Because local politics and economics were so dominated by large industry, its citizens were reluctant to directly challenge these industries. Instead, local women's groups studied local pollution problems and presented their general findings to the public. These activities raised public awareness and resulted in increased support for local leftist politicians because leftist administrations had succeeded in cutting pollution in their cities. Kitakyushu's conservative mayor and local industry both became concerned that leftists would win the next local elections if pollution was not reduced. Thus the municipal government utilised scientific pollution data and prepared individualised pollution reduction recommendations in sulphur oxide pollution control agreements, which were accepted and complied with by all local industries. The result was a significant reduction in air pollution without the need for active intervention from Kitakyushu's citizenry. Cientificos sociales han descrito las protestas anti-polución urbana de Japon en los años 60 como un fenómeno nacional. Sinembargo, en Kitakyushu, ciudad industrial japonesa más polucionada en ese tiempo, no se desarrollóningún movimiento ciudadano evidente. Debido a que las políticas locales y económicas eran dominadas por la gran industria, sus ciudadanos no estaban dispuestos a retar directamente estas industrias. En lugar de eso, grupos locales de mujeres estudiaron problemas locales de polución y presentaron sus resultados al público. Estas actividades despertaron conciencia pública y resultaron en el incremento del apoyo para políticos izquierdistas locales debido a que las administraciones izquierdistas habían triunfado en la reducción de la polución en sus ciudades. El alcalde conservador y la industria local de Kitakyushu empezaron a preocuparse que los izquierdistas ganarían las próximas elecciones locales si la polución no era reducida. Asíque, el Gobierno Municipal utilizó información científica sobre polución y preparó recomendaciones de reducción de polución individualizada en acuerdos de control de polución en oxído sulfurico, los cuales fueron aceptados y obedecidos por todas las industrias locales. El resultado fue una significativa reducción en la polución del aire sin la necesidad de la intervención activa de parte de la ciudadania de Kitakyushu.  相似文献   
183.
This paper aims to practically contribute to the literature on the use of cost–benefit analysis (CBA) and economic evaluation in environmental decision-making through a practical case study: the implementation of the Water Framework Directive (WFD) in France, for the first cycle (2010–2015). The WFD requires that Member States achieve “good status” for all water bodies in 2015. However, exemptions can apply, if justified, on natural, technical or economic reasons. For the latter, EU guidance documents recommend to use CBA. In France, the water agencies carried out 710 CBAs on proposed restoration projects for water bodies. This article reports on this experience. Issues concerning these analyses are discussed, especially the assessment of non-market benefits. Finally, this article questions the use of economic analysis in the implementation of environmental policy.  相似文献   
184.
Using two very different empirical settings, this paper emphasizes the required conditions for the successful crafting of sustainable institutions. In the first setting, different farmer groups in Cambodia and Vietnam try to establish a collective approach for small-scale community-based aquaculture and fail. In the second setting, the collective initiatives of urban women in India are analysed. The Indian women succeed in their objective of a fuel transition from firewood to gas cookers using a cooperative approach. Ostrom's variables identified in the “Multitier Framework for Analyzing Social–Ecological Systems (SES)” (Ostrom, 2007) are applied to local collective action initiatives in both settings to understand which factors make some of the groups succeed in their objectives and others fail. This research highlights the complexity as well as the uniqueness of different SESs. At the same time, the paper contributes to demonstrating the usability of the SES and certain variables to estimate the likelihood of success of self-organisation and crafting of rules. It highlights the relevance of certain conceptual variables for sustainable or unsustainable outcomes for different cases.  相似文献   
185.
Twin–twin transfusion syndrome (TTTS) is attributed to trans-anastomotic transfusion between twins. Anastomoses are ubiquitous in monochorionic (MC) placentae, yet TTTS develops in only 15%. Although ex vivo and in vivo studies fail to identify a unique anastomotic signature, TTTS placentae are typically associated with an imbalance in unidirectional arteriovenous anastomoses with absent bidirectional anastomoses. Doppler detection of an artery-artery anastomosis reduces the chance of TTTS, whereas, in those that develop the disease, it improves stage-independent survival. Selective laser is often curative, but an increasingly recognized risk of persistent or reverse TTTS may be attributable to atypical arteriovenous anastomoses not identifiable from the chorionic plate. Simple dysvolaemia fails to explain several phenotypic features, including haematological concordancy, recipient hypertension, and reversibly absent end diastolic flow in the donor. The renin-angiotensin system is upregulated in the donor and downregulated in the recipient's kidneys, while paradoxically raised renin levels in the recipient may contribute to raised afterload along with endothelin. Although research is limited in humans by therapy and the lack of a suitable experimental model, further studies of placental and vascular pathophysiology may not only refine current treatment modalities but may also, in addition, suggest further avenues for downstream management such as genetic predisposition testing or pharmacological intervention. Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   
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The identification of small supernumerary marker chromosomes (SMCs) and the elucidation of their clinical significance remain two of the problems in classical human cytogenetics. We observed a small supernumerary ring in amniotic fluid cell cultures and identified its origin as r(2)(p10q11.2) and its extent by means of fluorescent in situ hybridisation (FISH). Uniparental disomy (UPD) was excluded by microsatellite analysis using polymorphic markers localised in the same region. On the basis of normal ultrasonographic checks, the patient decided to continue the pregnancy. A normal female was delivered at term and subsequent neonatal follow-ups confirmed the normal phenotype and development. In the present case, genetic counselling was not helpful because of the absence of reference cases. Detailed characterisation made it possible to correlate the normal baby phenotype with the trisomic 2p10-2q11.2 genomic region. Further molecular cytogenetic investigations of SMCs classified by DNA content and pregnancy outcome data should improve genetic counselling and risk evaluation. Copyright © 2001 John Wiley & Sons, Ltd.  相似文献   
190.
In an open economy, embodied carbon dioxide emissions in international trade should be taken into consideration to scientifically define each country’s emissions responsibility. In this study, a multiregional input–output model is constructed to calculate the embodied carbon dioxide emissions of 25 World Trade Organization members, including China, according to the producer–consumer shared responsibility principle. The study indicates that: it is fairer and more efficient to identify each country’s carbon dioxide emissions responsibility according to the shared responsibility principle; China’s producer responsibility is 1.4 times that of the USA, while China’s consumer responsibility is only one-tenth that of the USA; according to the producer responsibility principle, China shoulders the greatest responsibility. According to the producer–consumer shared responsibility principle, China’s responsibility shows a large decrease. Resource endowment, economic development stage, and trade structure account for the abovementioned changes in China’s emissions responsibility.  相似文献   
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