Heart arrhythmia beat. Any part of the heart that initiates an impulse without waiting for the sinoatrial node is called an ectopic focus and is, by definition, a pathological phenomenon. This may cause a single premature beat now and then, or, if the ectopic focus fires more often than the sinoatrial node, it can produce a sustained abnormal rhythm. Rhythms produced by an ectopic focus in the atria, or by the atrioventricular node, are the least dangerous dysrhythmias; but they can still produce a decrease in the heart's pumping efficiency, because the signal reaches the various parts of the heart muscle with
Diskless node as thin clients. Moreover, thin client computers are increasing in power to the point where they are becoming suitable as fully-fledged diskless workstations for some applications. Both thin client and diskless node architectures employ diskless clients which have advantages over fat clients (see above), but differ with regard to the location of processing. Diskless node A diskless node (or diskless workstation) is a workstation or personal computer without disk drives, which employs network booting to load its operating system from a server. (A computer may also be said to "act as a diskless node", if its disks are unused and