The performance of limestone‐derived CaO during many (>1000 in some cases) calcination and carbonation cycles is reported. After 150 cycles, the calcium utilization during carbonation reached a minimum value between 4 and 17%, with the asymptotic level depending strongly on the carbonation time. With the aid of mechanistic studies including investigations on sorbent surface topology by SEM and mercury intrusion, a mechanism for pore evolution during the cyclic capture is proposed consistent with the experimental observations. © 2008 American Institute of Chemical Engineers AIChE J, 2008

A learning curve exists for stereotactic breast biopsy. Significantly higher technical success rates and lower false-negative rates were observed after the first five to 20 cases for 14-gauge automated core biopsy and after the first five to 15 cases for 11-gauge vacuum-assisted biopsy. Even after a radiologist has experience with stereotactic biopsy, changes in equipment may result in a new learning curve.