Photocathodes that provide high electron-spin polarization (ESP) and high quantum efficiency (QE) can significantly enhance the physics capabilities of electron accelerators. We report recordlevel QE from a high-polarization strained GaAs/GaAsP superlattice photocathode fabricated with a Distributed Bragg Reflector (DBR). The DBR photocathode technique enhances the absorption of incident laser light thereby enhancing QE, but as literature suggests, it is very challenging to optimize all of the parameters associated with the fabrication of complicated photocathode structures composed of many distinct layers. Past reports of DBR photocathodes describe high polarization but typically QE of only $1%, which is comparable to QE of high polarization photocathodes grown without a DBR structure. This work describes a strained GaAs/GaAsP superlattice DBR photocathode exhibiting a high polarization of 84% and significantly enhanced QE of 6.4%.

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In a time of data science, online crowdsourced data and advanced data analytics would be a waste of resources and knowledge if these tools wouldn't assist urban planning. This paper uses sentiment analysis to understand policy debates' present in online media in a re-urbanized city and discusses how these tools and new datasets can help planners and inform new waves of policy by including groups that tend to be underrepresented in traditional consultation meetings. Modern reurbanization is an emergent phenomenon that occurs in cities that experienced urban shrinkage in the past decades. Urban policies proposed to the "new" regrowing cities should meet challenges of old shrinking consequences and new regrowing demands. Nowadays, policy-makers need to hear the voice from different age groups, some use new, non-traditional media in policy debates. Online media data has the potential to provide quasi-live feedbacks, to supply the traditional opinion surveys. We applied sentiment analysis in the selected casethe Integrated Urban Development Concept (INSEK) Leipzig 2030to evaluate public opinion. While results show that public attention was low, the policy seems to be welcome, with the public showing more interests in regrowth topics than shrinkage issues.