Putting a stock windfall to philanthropic use, the head of Los Angeles County’s public-health service has pledged $50-million toward medical studies at the University of California, Los Angeles, according to the Los Angeles Times.

The gift from Dr. Jonathan Fielding and his wife, Karin, is the largest by a factor of 10 to the UCLA’s School of Public Health. The school, where Dr. Fielding has been a faculty member for 30 years, will be renamed for the couple.

The Fieldings’ wealth, previously unknown to colleagues, comes from stock in Dimensional Fund Advisors, a Texas investment firm that manages assets worldwide. The UCLA public-health school will receive income from the stock and all profit if it is sold.

The money will be used for scholarships, faculty recruitment, research, and building improvements and to endow a chair in population health, a field that examines the effect of housing, education, and transportation on people’s health.