“Tiny biological batteries” can change the cell membrane’s electrical properties—a discovery that has big implications for health, as many essential cellular processes hinge upon precise electrical activity.

Fertility rates in much of Sub-Saharan Africa remain high, despite declining child mortality and improved access to contraceptives and female education — factors that generally lead to smaller families and improved economic conditions in developing countries. A new study from the University of Illinois Urbana-Champaign looks at men’s and women’s desired fertility in rural Tanzania, gauging some of the factors that influence how many children they want.