This paper examines a new topology of the AC‐AC Z‐source converter based on asymmetric Gama structure is proposed. The proposed converter has all the common features such as common ground between input and output, realizing the continuous input current and the ability of boost in‐phase and buck out of‐phase. In order to generate a high voltage gain in the proposed converter, a coupled inductor with Gama structure is used. In this structure, as the turn ratio approaches to one, it gives a higher voltage gain. In order to damping the voltage and current overshoots on the proposed converter switches, a safe commutation strategy is used. Due to the specific topology of the proposed converter, the output filter has been eliminated, so the size and cost of the proposed converter are reduced. Circuit analysis and performance principles are presented in detail and a laboratory prototype implemented to confirm the practicality of the proposed converter.

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Here, a buck-boost DC-DC converter based on coupled inductor is proposed. At first, the proposed converter's operation modes and theoretical relations are reviewed and analyzed. Then, to operate the proposed converter in continuous conduction mode (CCM), the optimal value of the elements is designed. Then, the comparison results are presented to highlight the advantages and disadvantages of the proposed converter. The proposed DC-DC converter has benefits such as high conversion ratio capability, continuous input current, common ground, and low voltage stress on elements. Finally, the experimental results of the proposed converter's prototype are presented for both buck and boost operations to confirm the theoretical relations and verify the claims made.

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Tuberculosis (TB) is a deadly infection and caused 1.4 million deaths in 2018. Assessing the geographic distribution of major lineages of Mycobacterium tuberculosis can contribute greatly to TB control. Mycobacterial interspersed repetitive unit variable number tandem repeat (MIRU-VNTR) typing is commonly used to differentiate various lineages of M. tuberculosis . A total of 2747 clinical specimens were collected consecutively from October 2018 through June 2019. Clinical isolates were identified as M. tuberculosis using standard biochemical tests. The standard 15-locus MIRU-VNTR typing was used for the genotyping of clinical isolates. Drug susceptibility testing was performed using the conventional proportion method. From the collected specimens, 100 were culture positive for M. tuberculosis . Using MIRU-VNTR, 99 different patterns were detected among the 100 isolates. They were distributed in one cluster comprising two strains and 98 unique patterns. Most of our isolates were similar to New-1 and Delhi/CAS strains. Of the M. tuberculosis isolates, 83 (83.0%) were pan-susceptible and 17 (17.0%) were resistant to at least one drug. Our study showed that MIRU-VNTR is a useful method for studying the genetic diversity of M. tuberculosis isolates in different regional settings and will help the health authorities to construct a preventive programme for TB.