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991.
This paper makes a distinction between three theoretical frameworks that have been highly influential in the discourse on innovation, competitiveness and sustainability: sectoral systems of innovation (SSI), technological innovation systems (TIS) and socio-technical systems (ST-Systems). These frameworks share a common systems approach to innovation but are often positioned as different bodies of literature that correspond to different epistemic communities. This paper is explorative and conceptual in nature. It presents a systematic comparative review of SSI, TIS and ST-Systems based on the following analytical dimensions: (1) system boundaries, (2) actors and networks, (3) institutions, (4) knowledge, (5) dynamics and (6) policy approach. In the concluding section commonalities and differences, of the three approaches, are presented and suggestions for complimentarily are made.  相似文献   
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Abstract

Safening activities of natural compounds DIMBOA, DIBOA, and MBOA, as well as synthetic 1,4‐benzoxazin‐3‐ones were tested against acetochlor and EPTC injuries to maize. No safening activities of natural products and from low to moderate activity of synthetic benzoxazinones were observed. In order to explain inefficacy of natural compounds we studied the influence of these molecules on enzymes participating in metabolic detoxication of acetochlor and EPTC. Pretreatment with DIMBOA elevated maize cytochrome P450 levels. Pretreatments with chemicals containing 1,4‐benzoxazin‐3‐one backbone did not alter glutathione S‐transferase enzyme activities. However, all natural products inhibited glutathione S‐transferase activity of roots and shoots in vitro after addition to the enzyme. Safening ineffectiveness of natural hydroxamic acids may be explained by their inhibitory effects on GST enzymes due to their reaction with sulfhydryl groups on the enzyme.  相似文献   
997.
Directive 2008/98/EC released by the European Union represents a significant step forward in all relevant aspects of waste management. Under the already established, extended produced responsibility (EPR) principle, new policies have been enunciated to continuously achieve better overall environmental performance of key products throughout their life phases. This paper discusses how the directive is being articulated in Spain by the main integrated management system (IMS) for end-of-life (EOL) tyres since its creation in 2006. Focusing on the IMS technological, economic and legal aspects, the study provides a global perspective and evaluation of how the IMS is facing the current issues to resolve, the new challenges that have appeared and the management vision for the coming years.  相似文献   
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The agro-food domain in Europe is characterized by the appearance of recurrent unwanted surprises. These events, although causing obvious physical consequences, in essence depart from the expectations of the society. We argue that this unstable situation is best understood as an identity crisis of agriculture rather than as a contingent crisis of a specific economic sector. Thus the present agro-food crisis is in fact a crisis of identity. This is clearly reflected by the cohabitation within the agro-food policy domain of different, often contradictory, policy discourses, namely: free tradism, multifunctionality, and agroecology. All of them try to impose their particular visions. All of them struggle to issue the policy measures they conceive as appropriate.  相似文献   
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We applied two methods to assess vulnerability to climate change in Mexico’s agricultural sector. The first one was a principal component analysis (PCA) that weighted each variable separately. For the second one, we integrated the variables in a linear array in which all variables were weighted equally, and then, we used the arithmetic sum of the sub-indices of exposure and sensitivity minus the adaptive capacity to obtain the vulnerability index. We discuss the similarities and differences between two methods with respect to municipal-level maps as the outputs. The application of the method for the agricultural sector in Mexico gave us the spatial distribution of the high- and very-high vulnerability categories, which we propose as a tool for policy. The methods agreed that the very-high vulnerability category is present in 39 municipalities. Also we found that 16 % of the total population in the country is located in high-exposure areas. In addition, 41 % lives in municipalities identified as highly-sensitive. In terms of adaptive capacity, 20 % of the population lives in 1273 municipalities with low-adaptive capacity. Finally, we discuss the need for information regarding vulnerability at the national level to guide policies aimed at reducing exposure and sensitivity and increasing adaptive capacity.  相似文献   
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This paper explores the effects of industrialization policy on environmental regulation in Puerto Rico, focusing on implementation of the Environmental Impact Statement (EIS) review process. Adopted in 1970, the EIS process has been transformed to pave the way for extensive use of a concise, alternative mechanism for analysing project environmental impacts, one with less opportunity for public input. This policy shift, virtually replacing the full‐scale EIS, occurred as a way to mediate the conflict between environmental policy and industrialization policy. Formal public participation in environmental decision‐making became the target of reform by the Puerto Rican Government because it perceived that public review was interfering with the location of industry.  相似文献   
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