Although niche grassroots initiatives can push bottom-up sustainability transitions, they can face problems in forming a more global niche and in scaling their innovative solutions to a regime level. A thorough literature review shows scholarly agreement on the assumption that universities and non-governmental organisations (NGOs) can support sustainability transition in the acceleration phase by intermediating within niches and between niches and regimes. As in-depth research and a reality check on successful intermediary strategies in this context are still lacking, this paper aims to contribute to a conceptual framework that integrates the NGOs and universities expected activities in existing literature and relates them to one another. We develop such a framework and test it in three case studies from the plastic revaluation field, comparing and drawing on the perspectives of niche, intermediary and regime actors. Findings confirm the conceptual framework and suggest changes and extensions. We enhance existing knowledge by providing detailed insights into successful intermediary activities in these innovation systems and draw conclusions for policymakers.

中文翻译：

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非政府组织和大学作为基于草根倡议的可持续性转型的过渡中介

尽管利基草根倡议可以推动自下而上的可持续性转型，但它们在形成更具全球性的利基以及将其创新解决方案扩展到政权层面时可能会面临问题。全面的文献综述表明，学术界一致认为大学和非政府组织 (NGO) 可以通过在利基内部以及利基和制度之间进行中介来支持加速阶段的可持续性转型。由于在这种情况下仍然缺乏对成功中介策略的深入研究和现实检查，本文旨在为一个概念框架做出贡献，该框架将现有文献中非政府组织和大学的预期活动整合在一起，并将它们相互联系起来。我们开发了这样一个框架，并在塑料重估领域的三个案例研究中对其进行了测试，比较和借鉴利基、中介和政权行为者的观点。调查结果确认了概念框架并建议了更改和扩展。我们通过提供有关这些创新系统中成功中介活动的详细见解来增强现有知识，并为决策者得出结论。