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Magnetic semiconducting materials offer tremendous prospects for spin electronics but is challenging to achieve room-temperature ferromagnetism with unambiguous origin. Herein, a non-stoichiometry strategy is proposed to induce tunable magnetization in MoSe2−x nanoflowers via vacancy-controlled 2H–1T phase transition. The resultant MoSe2−x exhibits robust room-temperature ferromagnetism with significant positive correlation to the content of 1T phase and 2H–1T interfaces. Significant magnetic hysteresis and Curie transition above room temperature have been achieved, confirming the ferromagnetic feature of MoSe2−x. To examine the origin of ferromagnetism, formation energy and spin-polarized calculations have been conducted, indicating that the Se vacancy is beneficial for the formation of the 1T phase and interfacial spin polarization. Localized magnetic moments induced at the 2H–1T interfaces exhibit enhanced magnetism as compared to the net moments from the 1T orbital splitting, giving rise to strong coupling bound magnetic polarons. This work not only advances the understanding on the origin of magnetism in magnetic semiconductors, but also provides an effective route to generate ferromagnetism by defect and/or interface engineering that could be applied to multiferroics, spintronics, and valleytronics. [ABSTRACT FROM AUTHOR]

Background: Polycystic ovary syndrome with insulin resistance (PCOS-IR) is the most common endocrine and metabolic disease in women of reproductive age, and low fertility in PCOS patients may be associated with oocyte quality; however, the molecular mechanism through which PCOS-IR affects oocyte quality remains unknown., Methods: A total of 22 women with PCOS-IR and 23 women without polycystic ovary syndrome (control) who underwent in vitro fertilization and embryo transfer were recruited, and clinical information pertaining to oocyte quality was analyzed. Lipid components of follicular fluid (FF) were detected using high-coverage targeted lipidomics, which identified 344 lipid species belonging to 19 lipid classes. The exact lipid species associated with oocyte quality were identified., Results: The number (rate) of two pronuclear (2PN) zygotes, the number (rate) of 2PN cleaved embryos, and the number of high-quality embryos were significantly lower in the PCOS-IR group. A total of 19 individual lipid classes and 344 lipid species were identified and quantified. The concentrations of the 19 lipid species in the normal follicular fluid (control) ranged between 10 -3 mol/L and 10 -9 mol/L. In addition, 39 lipid species were significantly reduced in the PCOS-IR group, among which plasmalogens were positively correlated with oocyte quality., Conclusions: This study measured the levels of various lipids in follicular fluid, identified a significantly altered lipid profile in the FF of PCOS-IR patients, and established a correlation between poor oocyte quality and plasmalogens in PCOS-IR patients. These findings have contributed to the development of plasmalogen replacement therapy to enhance oocyte quality and have improved culture medium formulations for oocyte in vitro maturation (IVM)., Competing Interests: Authors BL and SQ were employed by Lipid ALL Technologies Company Limited. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Zhang, Wang, Di, Zhang, Liu, Zhang, Li, Qi, Cao, Liu, Liu and Xu.)

Safe and efficient hydrogen storage is one of the key technologies for the widespread utilization of hydrogen energy. Formic acid (FA) is regarded as a safe and convenient chemical hydrogen storage material. However, the lack of highly efficient heterogeneous catalysts hinders its practical application. Herein, we presented a facile wet-impregnated deposition method to synthesize ultrafine AuPd alloy nanoparticles anchored on TiO 2 nanosheets (AuPd/TiO 2 nanosheets) which were used as high efficient catalysts for the dehydrogenation of FA. TiO 2 nanosheets were calcined at different temperatures to modify the catalytic activity of catalyst. AuPd/TiO 2 nanosheets-400 exhibits the superior activity for catalyzing the FA to release 96% of overall hydrogen content with an initial turnover frequency value of 592 mol H 2 mol -1 metal h -1 at 25 °C and low activation energy of 11.8 kJ mol -1 . Detailed characterizations show that the superior catalytic performance can be ascribed to the alloy structure of AuPd centers, the phase and crystallinity of TiO 2 nanosheets, and the strong electron transfer interaction between AuPd nanoparticles and TiO 2 nanosheets substrate.