Each interquartile increase ( @,@ / cm ) in UFP exposure was associated with a @ % ( @ % CI : -@ , -@ ) decrease in reactive hyperemia index ( a measure of micro-vascular function ) and each @ ppb increase in O exposure corresponded to a @ % ( @ % CI : @ , @ ) increase in systolic blood pressure and a @ % ( @ % CI : @ , @ ) increase in diastolic blood pressure @-hours after exposure .