Publications by authors named "R K Tan"

Under mild visible light conditions, formates facilitate C-O cleavage the EDA complex and SCS strategy, yielding α-carbonyl alkyl radicals. These radicals then react with olefins under air conditions, leading to the synthesis of diaryl 1,4-dicarbonyl compounds. Mechanistic studies reveal that α-formyloxy ketone is generated by the reaction between α-brominated acetophenone and formates, followed by the formation of the EDA complex.

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Five previously undescribed phenylpyridones, designated as citridones H-L (1-5), along with seven known compounds, were characterized from the rice medium culture of the Cineraria repanda-derived endophytic fungus Penicillium oxalicum. Their structures were elucidated through detailed interpretation of UV, NMR, and HR-ESI-MS data. The absolute configurations of C-2 and C-3 in compounds 1-4 were determined by spectroscopic analysis and ECD calculations, while the C-5' configurations were established through computational C NMR and DP4+ analyses.

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Background: Ventricular tachycardia (VT) substrate characteristics before transcatheter pulmonary valve replacement (TPVR) in repaired tetralogy of Fallot (rTOF) are unknown.

Objectives: In this study, the authors sought to evaluate substrates for sustained monomorphic VT before TPVR in rTOF.

Methods: Retrospective (2017 to 2021) and prospective (commencing 2021) rTOF patients with native right ventricular outflow tract referred for electrophysiology study (EPS) before TPVR were included.

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Objectives: This analysis evaluated the cost-effectiveness of inclisiran plus standard of care (SoC; comprising statins, ezetimibe, and fenofibrate) in primary hypercholesterolemia or mixed dyslipidemia from a Singapore healthcare system perspective. Inclisiran + SoC was separately compared with SoC, alirocumab + SoC, and evolocumab + SoC.

Methods: A lifetime Markov model in the United Kingdom (UK) was adapted to the Singapore setting.

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Here we report a simple self-masking technique for fabricating bioinspired broadband antireflection coatings on both single-crystalline and multicrystalline silicon wafers with the assistance of a polyimide tape. Subwavelength-structured moth-eye nanopillars, which exhibit superior antireflection performance over a broad range of visible and near-IR wavelengths, can be patterned uniformly on the wafer surface by applying a chlorine-based reactive ion etching (RIE) process. The resulting random nanopillars show improved antireflection properties compared with ordered nanopillars templated by colloidal lithography under the same RIE conditions.

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