Abstract: Human monophenotypic cloned cell lines of megakaryocytic lineage are established in vitro through use of adherent stromal cells in long term human bone marrow culture. Long term bone marrow cultures are used for initial adaptation of the cells to culture conditions. Once adapted, cells of the human in vitro cell lines are weaned from the stromal layer until they proliferate in the complete absence of any feeder layer. Seed cells for establishment of human in vitro cell lines were derived from a human solid tumor designated as ATCC CRL 9139 xenograft. Cells of one cloned in vitro cell line designated as CHRF-288-11 exhibits a karyotype and markers characteristic of megakaryocytes and platelets. Cells of the CHRF-288-11 cell line express platelet peroxidate, platelet factor IV, platelet Ca.sup.++ -ATPase, gpIIbIIIa, factor VIII, and MY7, MY9 and HLA-Dr antigens. CHRF-288-11 cell line exhibits a constant karyotype (50, XY).

Abstract: Information-theoretic notions are employed to establish the predictability of a random number generated from a circuit exhibiting chaos in order to obtain a number from a sequence of numbers with a known level of randomness and security. The method provides a measure of information loss whereby one may select the number of iterations before or between bit sampling in order to extract a secure pseudo-random number. A chaotic output is obtained by use of a sample and hold circuit coupled in a feedback loop to a variable frequency oscillator, such as a voltage controlled oscillator circuit, and operated with a positive Lyapunov exponent. A source signal generator, such as a periodic wave generator, provides a driving signal to the sample and hold circuit.