in order to study the periplasmic expression of human growth hormone (hgh) in escherichia coli, the related cdna was inserted in two expression plasmids carrying pelb signal peptide, one with lac bacterial promoter and the other with a bacteriophage t7-based promoter. the recombinant plasmids were moved to tg1 and bl21 strains of e. coli, respectively. to induce the expression systems, iptg and...

accurate and correct performance of controller in cruise control systems is important. hence, in such systems, controller should optimize itself against noise and probable changes in system dynamic. as a matter of fact, in this article three approaches have been conducted to-ward this purpose: mit, direct estimation and indirect estimation. these approaches are used as controllers to track refe...

In an environment such as underwater channel where placing test equipments are difficult to handle, it is much practical to have hardware simulators to examine suitably designed transceivers (transmitter/receiver). The simulators of this kind will then allow researchers to observe their intentions and carry out repetitive tests to find suitable digital coding/decoding algorithms. In this p...

A recorded nerve signal via an electrode is composed of many evokes or action potentials, (originated from individual axons) which may be considered as different initial sources. Recovering these primitive sources in its turn may lead us to the anatomic originations of a nerve signal which will give us outstanding foresights in neural rehabilitations. Accordingly, clinical interests may be r...

Intracellular Ca2+ oscillations are often a response to external signals such as hormones. Changes in the external signal can alter the frequency, amplitude, or form of the oscillations suggesting that information is encoded in the pattern of Ca2+ oscillations. How might a cell decode this signal? We show that an excitable system whose kinetic parameters are modulated by the Ca2+ concentration ...