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551.
552.
Dries Hegger Annemarie Van Zeijl-Rozema Carel Dieperink 《Regional Environmental Change》2014,14(3):1049-1062
In various countries, actors try to reconcile climate science and policy through joint knowledge production (JNP). While many conceptual analyses of JNP exist, empirical studies that actually try to assess JNP processes are rare. This paper aims to fill this gap through an empirical analysis of the ‘Hotspot Zuidplaspolder’ project in which scientists, policymakers and other actors collaboratively looked for ways to ‘climate proof’ existing plans for urban development in one of the deepest polders of the Netherlands. The analysis is done by identifying and explaining the credibility and salience of the knowledge produced as well as the perceived legitimacy of the JNP process. Seven success factors derived from existing literature were used in the analysis. Stakeholders appeared to evaluate this project as positive, but the analysis shows that criteria and thresholds regarding success differ between the actors involved. We found three underlying design principles that should be followed to enhance the success of future JNP projects. First, it is necessary to organize several instances for reflection on the project processes. Second, new reward structures are needed to stimulate actors to take new initiatives and come up with creative ideas. Third, projects and programs should provide room to make mistakes and learn from them. This first set of empirical design principles for JNP is useful but should be further refined and nuanced in order to better deal with the social complexity of climate change and other wicked problems. 相似文献
553.
Diana W. Bianchi Tim Van Mieghem Lisa G. Shaffer Brigitte H. W. Faas Lyn S. Chitty Alessandro Ghidini Jan Deprest 《黑龙江环境通报》2014,34(1):1-5
本文提出怎样理解产学研相结合的问题,并从产学研不同层面进行分析,提出以市场为目标、以制度为保证实现产学研有效结合的思路。 相似文献
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Tarek Abichou Koenraad Mahieu Lei Yuan Jeffery Chanton Gary Hater 《Waste management (New York, N.Y.)》2009,29(5):1595-1601
Previous publications described the performance of biocovers constructed with a compost layer placed on select areas of a landfill surface characterized by high emissions from March 2004 to April 2005. The biocovers reduced CH4 emissions 10-fold by hydration of underlying clay soils, thus reducing the overall amount of CH4 entering them from below, and by oxidation of a greater portion of that CH4. This paper examines in detail the field observations made on a control cell and a biocover cell from January 1, 2005 to December 31, 2005. Field observations were coupled to a numerical model to contrast the transport and attenuation of CH4 emissions from these two cells. The model partitioned the biocover’s attenuation of CH4 emission into blockage of landfill gas flow from the underlying waste and from biological oxidation of CH4. Model inputs were daily water content and temperature collected at different depths using thermocouples and calibrated TDR probes. Simulations of CH4 transport through the two soil columns depicted lower CH4 emissions from the biocover relative to the control. Simulated CH4 emissions averaged 0.0 g m?2 d?1 in the biocover and 10.25 g m?2 d?1 in the control, while measured values averaged 0.04 g m?2 d?1 in the biocover and 14 g m?2 d?1 in the control. The simulated influx of CH4 into the biocover (2.7 g m?2 d?1) was lower than the simulated value passing into the control cell (29.4 g m?2 d?1), confirming that lower emissions from the biocover were caused by blockage of the gas stream. The simulated average rate of biological oxidation predicted by the model was 19.2 g m?2 d?1 for the control cell as compared to 2.7 g m?2 d?1 biocover. Even though its Vmax was significantly greater, the biocover oxidized less CH4 than the control cell because less CH4 was supplied to it. 相似文献
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Fetal cardiac function is increasingly recognized as a marker of disease severity and prognosis in selected fetal conditions. Magnetic resonance imaging (MRI) has been used in experimental (animal) fetal cardiology but the lack of a noninvasive fetal electrocardiogram (ECG) to trigger image acquisition remains a major limiting factor precluding its application in humans. Fetal medicine specialists are therefore limited to ultrasound to evaluate human fetal cardiac function. In this review, we aim to provide a complete overview of the different ultrasound techniques that can be used for fetal cardiac function assessment and we discuss their (theoretical) strengths and shortcomings. Conventional methods include M-mode assessment of ventricular contractility and Doppler assessment of the precordial veins and cardiac output (CO). More recent techniques such as the measurement of the myocardial performance index (MPI), myocardial motion analysis with tissue Doppler, speckle tracking and three-dimensional (3D) ultrasound techniques are also discussed. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
558.
Ana M. Contreras Elena Rosa Maylier Pérez Herman Van Langenhove Jo Dewulf 《Journal of Cleaner Production》2009,17(8):772-779
Cane sugar production by-products can be considered either as waste, affecting the environment, or as a resource when an appropriate valorization technology is implemented.This study is made with the objective of identifying and quantifying the aspects which have the largest environmental impact of four alternatives for using by-products and wastes from the cane sugar process and suggest improvements in the systems.For this analysis a cane sugar mill was chosen in Cuba and four alternatives were designed for the by-product valorization. The first alternative represents the conventional sugar production; its main characteristics are the use of synthetic fertilizers, pesticides, the bagasse combustion and the usage of molasses and agricultural wastes as animal food. Other wastes constitute emissions to the environment. Alternatives II, III and IV incorporate more use of by-products and wastes. Alternative II considers the use of wastewater, filter cake and ashes for the substitution of synthetic fertilizers. In Alternative III, the filter cake and wastewater are used for biogas production and Alternative IV integrates alcohol and biogas production into the sugar production process.The assessment is done by means of Life Cycle Assessment, according to the ISO 14040 series by using the SimaPro 6.0 LCA software, Ecoinvent database and the Eco-indicator 99 methodology. As a functional unit the daily sugar production of the mill was defined (216 t/d). The sugar was selected as main product and all the by-products were assumed to substitute other products on the market, avoided products.For the four alternatives, the agricultural stage shows the greatest impact due to land use, fuel and agrochemicals consumption. In the industrial stage, the electricity cogeneration with bagasse has the highest impact as to respiratory effects due to the emission of tiny particle material into the atmosphere. The major difference between the alternatives is found in the resource impact category. The advantage of producing alcohol, biogas, animal food and fertilizers from the by-products is made obvious through the comparative study for resource savings. 相似文献
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The aim of this study is to explain the occurrence of food sharing across primates. Defined as the unresisted transfer of
food, evolutionary hypotheses have to explain why possessors should relinquish food rather than keep it. While sharing with
offspring can be explained by kin selection, explanations for sharing among unrelated adults are more controversial. Here
we test the hypothesis that sharing occurs with social partners that have leverage over food possessors due to the opportunity
for partner choice in other contexts. Thus, we predict that possessors should relinquish food to potential mates or allies,
who could provide or withhold matings or coalitionary support in the future. We used phylogenetic analyses based on both maximum
likelihood and Bayesian approaches in a sample of 68 primate species to test these predictions. The analyses strongly indicate
that (1) sharing with offspring is predicted by the relative processing difficulty of the diet, as measured by the degree
of extractive foraging, but not overall diet quality, (2) food sharing among adults only evolved in species already sharing
with offspring, regardless of diet, and (3) male–female sharing co-evolved with the opportunity for female mate choice and
sharing within the sexes with coalition formation. These results provide comparative support for the hypothesis that sharing
is “traded” for matings and coalitionary support in the sense that these services are statistically associated and can thus
be selected for. Based on this, we predict that sharing should occur in any species with opportunities for partner choice. 相似文献