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This paper presents a novel coupled converter with high‐voltage insulation protection in magnetic isolated way by taking the case of heater/ignitor/keeper supply for powering discharge cathode in the space ion electric propulsion (EP) thruster. The topology, working principle and igniting timing, as well as the adaptive closed‐loop control and heating‐igniting interlock control are also illustrated. For the proposed converter, the coupled topology and control strategy only adopt three straddling magnetic components to realize all functions. Meanwhile, the number of electronic components suspending over the high‐voltage side of beam supply is small enough. Additionally, the test on the coupled converter prototype shows that, the maximum efficiency is 88.6%, close to the traditional tightly coupled supply; the proposed converter could realize the function of heating/igniting/keeping for the discharge cathode under the magnetic isolated way and corresponding control strategy; and there is no "spark phenomenon" for the converter during low‐pressure discharge test. Hence, the magnetic isolated way to obtain the physical separation between high‐voltage and low‐voltage side in the converter is useful to achieve the high‐voltage insulation protection. [ABSTRACT FROM AUTHOR]

Salmonella enterica, Staphylococcus aureus, Escherichia coli O157: H7, and Listeria monocytogenes may contaminate similar types of food and cause foodborne disease. The objective of this study was to develop a selective enrichment broth for simultaneous enrichment of Salmonella enterica, Staphylococcus aureus, Escherichia coli O157: H7, and Listeria monocytogenes (SSEL) using nalidixic acid, acriflavine, lithium chloride, and sodium cholate as selective agents. Developed SSEL broth not only enriched the target pathogens to 5 log10 CFU/ml after 18 hr incubation at 37°C with 10–100 CFU/mL of inoculation concentration, but also could successfully support the simultaneous enrichment of target pathogens with similar growth rates and inhibit the growth of most nontarget bacteria effectively. The enrichment effect of SSEL was confirmed by artificial contamination test coupled with multiplex PCR. In summary, SSEL has been shown to be a promising multiplex selective enrichment broth for the detection of the four pathogens on a single‐assay platform. [ABSTRACT FROM AUTHOR]