Langerhans' cell histiocytosis can manifest as three distinct clinicopathologic entities: acute disseminated Langerhans' histiocytosis (previously known as Letterer-Siwe disease), unifocal Langerhans' cell histiocytosis (previously known as eosinophilic granuloma).
average handle time (AHT) Average handle time (AHT) is a call center metric for the average duration of one transaction, typically measured from the customer's initiation of the call and including any hold time, talk time and related tasks that follow the transaction. AHT is a prime factor when deciding call center staffing levels.
Human reaction time is one of the most important factors in occupational selection. It is crucially significant in determining the psychophysiological capacities of persons to work as operators, pilots, cosmonauts, drivers, and so on.