Photochemical Radical Bicyclization of 1,5-Enynes: Divergent Synthesis of Fluorenes and Azepinones.

A dual nickel- and iridium-photocatalyzed radical cascade bicyclization reaction for the synthesis of highly complex molecular structures in an atom- and step-economic manner has been described. A series of radical precursors are utilized for the divergent synthesis of diversely substituted fluorenes and indenoazepinones bearing quaternary carbons by using cascade cyclization reactions of 1,5-enynes. This reaction is characterized by its mild conditions, broad substrate scope, excellent selectivity, and satisfactory yield including facile scale-up synthesis.

Ferroelectricity and Oxide Reliability of Stacked Hafnium-Zirconium Oxide Devices.

In this work, we investigate the ferroelectricity of stacked zirconium oxide and hafnium oxide (stacked HfZrO) with different thickness ratios under metal gate stress and simultaneously evaluate the electrical reliability of stacked ferroelectric films. Based on experimental results, we find that the stacked HfZrO films not only exhibited excellent ferroelectricity but also demonstrated a high performance on reliability. The optimized condition of the 45% Zr proportion exhibited a robust ferroelectric polarization value of 32.

Coenzyme Q defeats NLRP3-mediated inflammation, EMT/metastasis, and Warburg effects by inhibiting HIF-1α expression in human triple-negative breast cancer cells.

Coenzyme Q (CoQ) is a derivative quinone from Antrodia camphorata (AC) that exerts anticancer activities. This study examined the anticancer attributes of CoQ (0-4 µM) on inhibited anti-EMT/metastasis and NLRP3 inflammasome, and altered Warburg effects via HIF-1α inhibition in triple-negative breast cancer (MDA-MB-231 and 468) cells. MTT assay, cell migration/invasion assays, Western blotting, immunofluorescence, metabolic reprogramming, and LC-ESI-MS were carried out to assess the therapy potential of CoQ.

Enhanced thermoelectricity of three-dimensionally mesostructured BiSbTe nanoassemblies: from micro-scaled open gaps to isolated sealed mesopores.

We describe an innovative interfacial design concept and nanostructuring of novel BiSbTe (BST) nanoassembled films comprising unique air-solid interfaces from micro-scaled open gaps to isolated sealed mesopores, and high-quality solid-solid ones including the coherent grain boundaries and specific twins, utilizing pulsed laser deposition (PLD), for potentially activating multiple thermoelectric enhancing mechanisms. The unusual mesopore embedded BST films exhibit the highest power factor of ∼33 μW cm K, which is comparable to or higher than the previously reported values for BST, and the corresponding relatively low thermal diffusivity in contrast to that for dense pore-less BST films evidently reveals the crucial role of the three-dimensionally and densely arranged air-solid interfaces in significantly arising the phonon scattering.

Study of release speeds and bacteria inhibiting capabilities of drug delivery membranes fabricated via electrospinning by observing bacteria growth curves.

The study found that biodegradable drug delivery membranes that were fabricated from Poly(a-L-alanine) (PLLA) and chlorhexidine (CHX)-gluconate via electrospinning could steadily and continuously inhibit the growth of bacteria. Bacterial growth curves were used to evaluate on a real-time basis the relationship between drug delivery speeds of the membranes and growth rates of bacteria in different phases. The results showed that PLLA/CHX (50:50 in terms of volume) drug delivery membranes could do what drug delivery systems can normally do.

Dihydrobenzoic acid modified nanoparticle as a MALDI-TOF MS matrix for soft ionization and structure determination of small molecules with diverse structures.

Efficient structural characterization is important for quality control when developing novel materials. In this study, we demonstrated the soft ionization capability of the hybrid of immobilized silica and 2,5-dihydrobenzoic acid (DHB) on iron oxide magnetic nanoparticles in MALDI-TOF MS with a clean background. The ratio between SiO(2) and DHB was examined and was found to affect the surface immobilization of DHB on the nanoparticle, critically controlling the ionization efficiency and interference background.

Synthesis of alpha-(2-->5)Neu5Gc oligomers.

A facile synthesis of the sialic acid oligomers alpha-(2-->5)Neu5Gc (1) is presented. Monosaccharides 2-4 with suitable functionality were used as the building blocks. After selective removal of the paired carboxyl and amine protecting groups, the fully protected oligomers were assembled through consecutive coupling of the building blocks by well established peptide coupling techniques.