Face masks for the public during Covid-19: an appeal for caution in policy

As the Covid-19 crisis deepens, some researchers have argued for the widespread routine use of face masks in community settings, despite acknowledged gaps in the evidence base for the effectiveness of such a measure. We argue that such calls are premature, and risk neglecting important potential harms and negative consequences, known and unknown. We identify potential unintended consequences at multiple levels, from individual-behavioural to macrosocial, and suggest that it is far from clear that the benefits of widespread uptake of face masks, whether encouraged or enforced by public authorities, outweigh the downsides. Finally, we make the case for caution in communicating unequivocal messages about the scientific evidence for face mask use to policy, practitioner and public audiences, given continued scientific disagreement on the questio

Whirling skirts and rotating cones

Steady, dihedrally symmetric patterns with sharp peaks may be observed on a spinning skirt, lagging behind the material flow of the fabric. These qualitative features are captured with a minimal model of traveling waves on an inextensible, flexible, generalized-conical sheet rotating about a fixed axis. Conservation laws are used to reduce the dynamics to a quadrature describing a particle in a three-parameter family of potentials. One parameter is associated with the stress in the sheet, aNoether is the current associated with rotational invariance, and the third is a Rossby number which indicates the relative strength of Coriolis forces. Solutions are quantized by enforcing a topology appropriate to a skirt and a particular choice of dihedral symmetry. A perturbative analysis of nearly axisymmetric cones shows that Coriolis effects are essential in establishing skirt-like solutions. Fully non-linear solutions with three-fold symmetry are presented which bear a suggestive resemblance to the observed patterns.Comment: two additional figures, changes to text throughout. journal version will have a wordier abstrac

Innovation for tackling grand challenges : Cleantech industry dynamics and regional context

Grand challenges such as climate change put focus away from innovations and innovation policy as engines of economic growth towards fulfilling societal goals and sighting sustainable development. The literature on the geography of innovation has provided valuable insights on innovation activities of firms and industries and how they are positively influenced by co-location. In particular, short geographical distances have been found to facilitate trust, knowledge exchange and interactive learning processes that favour innovation. Innovation activities that address grand challenges have however gained surprisingly little attention in the discipline. This PhD thesis addresses this shortcoming and studies how and why change processes of industries towards more environmentally friendly modes in regions occur – or not occur. In other words, it engages in the question how such industry dynamics are enabled and/or constrained by regional context conditions. Consequently, it also puts central focus on the role, respectively possibilities and limitations of regional innovation policy to support desirable transformation processes. Its theoretical objective is to make a step towards a more coherent conceptual framework in the literature on economic geography regarding how to tackle grand challenges. The dissertation takes a regional innovation system perspective which is complemented by insights from the literature on socio-technical transitions.The development of a bio-based economy which draws on renewable resources from biomass possesses a key role in addressing grand challenges. Empirically, the dissertation studies industries in three different Swedish regions and their undertaking to increasingly, respectively more efficiently use biomass as raw material. The research design is informed by a critical realist perspective and draws largely on qualitative research methods. This PhD thesis spans four articles that are published in or submitted to peer-reviewed journals. The articles are preceded by an introductory chapter which provides the overall theoretical background and framing, the research design and central findings of the dissertation