The immune system can distinguish between normal, healthy cells and unhealthy cells by recognizing a variety of danger cues called danger-associated molecular patterns (DAMPs). Cells may be unhealthy because of infection or because of cellular damage caused by non-infectious agents like sunburn or cancer.he immune system can distinguish between normal, healthy cells and unhealthy cells by recognizing a variety of danger cues called danger-associated molecular patterns (DAMPs). Cells may be unhealthy because of infection or because of cellular damage caused by non-infectious agents like sunburn or cancer.
Time-weighted return. The time-weighted return (TWR) (or true time-weighted rate of return (TWRR)) is a method of calculating investment return. To apply the time-weighted return method, combine the return over sub-periods, by compounding them together, resulting in the overall period return. The rate of return over each different sub-period is weighted according to the duration of the sub-period.
For instance, suppose you needed to measure the total amount of time (expressed in hours and minutes) that elapsed from the time a loaded delivery truck with tandem drivers left your warehouse at noon on May 6, 2012, until the time the truck arrived at a customer location on May 8, 2012, at 8:45 a.m.