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Abstract High‐gain converters play a vital role in all industrial applications such as automobiles, motor drives, renewable energy systems, and railway transportation sectors. The conventional converters have low gain owing to high‐voltage stress on active MOSFET, diode and low efficiency related with high operating pulse ratio. To overcome the limitations associated with the conventional converters, this study proposes a non‐isolated configuration of multiport quasi‐resonant converter (MP‐QRC) with high gain. The proposed MP‐QRC has the merits of high‐voltage gain, reduced number of components, minimum conduction losses, realization of soft switching in the devices and improved reliability. Moreover, the proposed converter is scalable and can serve as a good candidate in microgrid environment where the integration of more than one input is essential. In this paper, first a comprehensive analysis of various operation modes and design constraints are presented. Further, the study is supported with a reliability evaluation of proposed converter based on component failure. Also, the futuristic behaviour of MP‐QRC under continuous conduction mode as a function of operational and environmental variables is investigated to ascertain the reliability. The steady‐state operation of the converter is demonstrated for off‐board electric vehilce (EV) charging using MATLAB/SIMULINK and experiments performed on a 300‐W test rig.

Joubert syndrome is a rare neurological manifestation usually present in late infancy or early childhood with characteristic episodes of abnormal breathing pattern along with the neurological and other systemic involvement.We report a case of confirmed Joubert syndrome present in the immediate neonatal period with isolated spells of oxygen desaturations not accompanied by the classically described breathing pattern and absent neurological symptoms causing delay in the diagnosis. Isolated oxygen desaturation episodes could be a presenting manifestation of Joubert syndrome in a neonatal period. [ABSTRACT FROM AUTHOR]

PURPOSE OF REVIEW: With the increasing incidence of obesity today, related complications such as diabetes, insulin resistance and hepatic steatosis are also becoming major concerns. Since these conditions share a common factor, aberrations in lipid metabolism, understanding the molecular changes that lead to abnormal lipid partitioning has become key to combating the obesity epidemic. RECENT FINDINGS: The enzyme stearoyl-coenzyme A desaturase 1 (SCD1) has been shown to be intimately involved in both the lipogenic as well as the lipid oxidative pathways. Our studies with the SCD1 mouse model have established that these animals are lean and protected from leptin deficiency-induced and diet-induced obesity. Consequently, they also show greater whole body insulin sensitivity than wild-type mice. SCD1 mice have decreased expression of genes of lipogenesis and increased expression of lipid oxidative genes. The main transcription factors controlling genes of lipid synthesis and oxidation are sterol regulatory element binding protein-1c and peroxisome proliferator-activated receptor-alpha (PPARalpha), respectively. Here, we review some studies that show that the effects of SCD1 deficiency on whole body adiposity may be partly dependent on sterol regulatory element binding protein-1c, but are most likely independent of peroxisome proliferator-activated receptor-alpha. SUMMARY: Our findings indicate that SCD1 is a key controller of lipid partitioning between lipogenesis and oxidation. While some questions regarding the molecular changes downstream of SCD1 deletion are yet to be answered, the studies outlined below clearly point to SCD1 as a highly promising target in combating obesity as well as related complications. [ABSTRACT FROM AUTHOR]