What's more, the mitochondria in cells that generate energy can, in many simple animals, function without oxygen for substantial periods of time. (newscientist.com)
Parts of the brain are unable to develop also if they are left to cry over substantial periods of time. (evolutionaryparenting.com)
Because we all spend substantial periods in situations of dependency, standard models of citizenship overlook the way such assisted agency is a normal part of every human life. (blog.politics.ox.ac.uk)