Abstract: The present invention relates to a composition comprising cyclic ketone peroxide and a phlegmatizer having a 95% boil-off point falling in the range of 220-265° C., most preferably 235-250° C. A preferred peroxide is cyclic methyl ethyl ketone peroxide. Preferably, a single phlegmatizer is used. Preferred phlegmatizers are Isopar® M and Soltrol® 170. The invention also pertains to the use of compositions according to this invention in (co)polymerization and polymer modification processes.

Abstract: There is provided a pacemaker system having the feature of delivering a ventricular safety pulse (VSP) following an early ventricular sense (VS), wherein the pacemaker automatically determines whether VSPs are to be delivered following early VSs, and if yes, with what timing. The pacemaker gathers data following delivered VSPs, which data contains information indicative of whether each early VS was indeed the result of a spontaneous R wave, or was due to crosstalk from a prior delivered atrial pace pulse. This data is processed and, when it presents a high statistical confidence, is used to make a determination of whether to respond with the assumption of a true R wave, or of crosstalk. If the data is not statistically significant, the pacemaker delivers VSPs in a normal fashion, e.g., at the end of a programmable VSP interval timed out following delivery of an atrial pace pulse.