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A new theory of city size, embodying ideas from economic complexity and cultural evolution, provides a rich basis for speculating on their economic structure and suggests hints as to how old cities might regenerate their past prosperity and how new ones might generate more success.
Confronting fears is a core component of cognitive behavioural therapies for anxiety disorders, but also a major hurdle for patients. A new study introduces a method for reducing defensive responses without consciously confronting the threatening cues, paving the way for fear-reducing therapies via unconscious processing.