The role of policy entrepreneurs in the transfer of policy between neighbourhood-level citizen initiatives: The case of Kiezblocks and Changing cities e.V., Berlin

With the transition towards more sustainable urban transport systems currently faltering in many European cities, a surge in local citizen initiatives attempting to accelerate this transition has been seen in Berlin. Exchange between these initiatives is crucial for their progress, though often their uncoordinated abundance and lack of an affiliation with a network of initiatives hinders this exchange from taking place. Aiming to aid in overcoming this barrier and widen the scope of past policy transfer studies from a top-down perspective to include a bottom-up perspective, this study applies the policy transfer framework as developed by Dolowitz and Marsh (2000) to uncover the role of policy entrepreneurs in the transfer of knowledge and ideas between neighbourhood-level citizen initiatives. Six in-depth semi-structured interviews with members of the initiatives and a document review inform the research, which is conducted in the context of Changing Cities e.V. and Kiezblock initiatives in Berlin. Results have shown that a policy entrepreneur has been able to accelerate the initiatives’ progress and facilitated the transfer of knowledge with the creation of an advocacy coalition as well as with the provision of crucial resources, such as an open-source database. While the facilitation of policy transfer is evident, the policy entrepreneur’s role also poses a risk: Being the central actor in the advocacy coalition and thereby the main source of input, the policy entrepreneur failed to incorporate actors active at different levels and scales into the network. This would have allowed for new knowledge and perspectives to enter the network and be used and circulated among the citizen initiatives, providing further benefit to these

Cues of intraguild predators affect the distribution of intraguild prey

Theory on intraguild (IG) predation predicts that coexistence of IG-predators and IG-prey is only possible for a limited set of parameter values, suggesting that IG-predation would not be common in nature. This is in conflict with the observation that IG-predation occurs in many natural systems. One possible explanation for this difference might be antipredator behaviour of the IG-prey, resulting in decreased strength of IG-predation. We studied the distribution of an IG-prey, the predatory mite Neoseiulus cucumeris (Acari: Phytoseiidae), in response to cues of its IG-predator, the predatory mite Iphiseius degenerans. Shortly after release, the majority of IG-prey was found on the patch without cues of IG-predators, suggesting that they can rapidly assess predation risk. IG-prey also avoided patches where conspecific juveniles had been killed by IG-predators. Because it is well known that antipredator behaviour in prey is affected by the diet of the predator, we also tested whether IG-prey change their distribution in response to the food of the IG-predators (pollen or conspecific juveniles), but found no evidence for this. The IG-prey laid fewer eggs on patches with cues of IG-predators than on patches without cues. Hence, IG-prey changed their distribution and oviposition in response to cues of IG-predators. This might weaken the strength of IG-predation, possibly providing more opportunities for IG-prey and IG-predators to co-exist

Ferrihydrite formation : the role of Fe13 Keggin clusters

Ferrihydrite is the most common iron oxyhydroxide found in soil and is a key sequester of contaminants in the environment. Ferrihydrite formation is also a common component of many treatment processes for clean-up of industrial effluents. Here we characterize ferrihydrite formation during the titration of an acidic ferric nitrate solution with NaOH. In-situ SAXS measurements supported by ex situ TEM indicate that initailly Fe13 Keggin clusters (radius ~0.45 nm) form in solution at pH 0.5 - 1.5, and are persistant for at least 18 days. The Fe13 clusters begin to aggregate above ~ pH 1, initially forming highly linear structures. Above pH ~ 2 densification of the aggregates occurs in conjunction with precipiation of low molecular weight Fe(III) speices (e.g. monomers, dimers) to form mass fractal aggregates of ferrihydrite nanoparticles (~ 3 nm) in which the Fe13 Keggin motif is preserved. SAXS analysis indicates the ferrihydrite particles have a core-shell structure consisting of a Keggin center surrounded by a Fe-depleted shell, supporting the surface depleted model of ferrihydrite. Overall, we present the first direct evidence for the role of Fe13 clusters in the pathway of ferrihydrite formation during base hydrolysis, showing clear structural continuity from isolated Fe13 Keggins to the ferrihydrite particle structure. The results have direct relevance to the fundamental understanding of ferrihydrite formation in environmental, engineered and industrial processes