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We herein disclose a mild and efficient access to chiral 3‐azabicyclo[3.1.0]hexanes via a Pd‐catalyzed asymmetric 5‐exo‐trig cyclization/cyclopropanation/carbonylation of 1,6‐enynes. Various nucleophiles, such as alcohols, phenols, amines and water, are well compatible with the reaction system. This reaction forms three C−C bonds, two rings, two adjacent quaternary carbon stereocenters as well as one C−O/C−N bond with excellent regio‐ and enantioselectivities. The products could be further functionalized to generate a library of 3‐azabicyclo[3.1.0]hexane frameworks. [ABSTRACT FROM AUTHOR]

Organic–inorganic halide perovskite solar cells (PSCs) are a new class of photovoltaic devices, which have attracted increasing interests due to high efficiency, low cost, and simple fabrication process. Although a remarkable enhancement in power conversion efficiency (PCE) has been achieved in the last decade, the stability issue, including high water/heat sensitivity and UV light‐induced degradation, has become one of the main obstacles for practical applications of PSCs. Herein, hydrophobic butyl acrylate with CO and CC groups is reported as a new additive to enhance the PCE and moisture/thermal stability of CH3NH3PbI3‐based PSCs, which improves the quality of the perovskite film by promoting defect passivation, constructing a suitable energy‐level alignment, and increasing the charge carrier lifetime in PSCs. Such an additive is easily introduced into PSCs without the need for thermal treatment, which is typically required by other additives, causing a negative effect on the efficiency. The CH3NH3PbI3‐based PSC with butyl acrylate additive shows a superior PCE of 20.0%, 19% higher than that of the unmodified device (16.8%), as well as much improved moisture/thermal stability. Herein, a facile way is provided to enhance the PCE and stability of CH3NH3PbI3‐based PSCs simultaneously, which facilitates the commercialization of PSCs. [ABSTRACT FROM AUTHOR]

Perovskite solar cells (PSCs) are highly promising next‐generation photovoltaic devices because of the cheap raw materials, ideal band gap of ≈1.5 eV, broad absorption range, and high absorption coefficient. Although lead‐based inorganic‐organic PSC has achieved the highest power conversion efficiency (PCE) of 25.2%, the toxic nature of lead and poor stability strongly limits the commercialization. Lead‐free inorganic PSCs are potential alternatives to toxic and unstable organic‐inorganic PSCs. Particularly, double‐perovskite Cs2AgBiBr6‐based PSC has received interests for its all inorganic and lead‐free features. However, the PCE is limited by the inherent and extrinsic defects of Cs2AgBiBr6 films. Herein, an effective and facile strategy is reported for improving the PCE and stability by introducing an N719 dye interlayer, which plays multifunctional roles such as broadening the absorption spectrum, suppressing the charge carrier recombination, accelerating the hole extraction, and constructing an appropriate energy level alignment. Consequently, the optimizing cell delivers an outstanding PCE of 2.84%, much improved as compared with other Cs2AgBiBr6‐based PSCs reported so far in the literature. Moreover, the N719 interlayer greatly enhances the stability of PSCs under ambient conditions. This work highlights a useful strategy to boost the PCE and stability of lead‐free Cs2AgBiBr6‐based PSCs simultaneously, accelerating the commercialization of PSC technology. [ABSTRACT FROM AUTHOR]

Co‐free Ni‐rich layered oxides are considered a promising cathode material for next‐generation Li‐ion batteries due to their cost‐effectiveness and high capacity. However, they still suffer from the practical challenges of low discharge capacity and poor rate capability due to the hysteresis of Li‐ion diffusion kinetics. Herein, based on the regulation of the lattice magnetic frustration, the Li/Ni intermixing defects as the primary origin of kinetic hysteresis are radically addressed via the doping of the nonmagnetic Si element. Meanwhile, by adopting gradient penetration doping, a robust Si−O surface structure with reversible lattice oxygen evolution and low lattice strain is constructed on Co‐free Ni‐rich cathodes to suppress the formation of surface dense barrier layer. With the remarkably enhanced Li‐ion diffusion kinetics in atomic and electrode particle scales, the as‐obtained cathodes (LiNixMn1−xSi0.01O2, 0.6≤x≤0.9) achieve superior performance in discharge capacity, rate capability, and durability. This work highlights the coupling effect of magnetic structure and interfacial chemicals on Li‐ion transport properties, and the concept will inspire more researchers to conduct an intensive study. [ABSTRACT FROM AUTHOR]

The pathological activation of cardiac fibroblasts (CFs) plays a crucial role in the development of pressure overload-induced cardiac remodelling and subsequent heart failure (HF). Growing evidence demonstrates that multiple microRNAs (miRNAs) are abnormally expressed in the pathophysiologic process of cardiovascular diseases, with miR-425 recently reported to be potentially involved in HF. In this study, we aimed to investigate the effects of fibroblast-derived miR-425-5p in pressure overload-induced HF and explore the underlying mechanisms. C57BL/6 mice were injected with a recombinant adeno-associated virus specifically designed to overexpress miR-425-5p in CFs, followed by transverse aortic constriction (TAC) surgery. Neonatal mouse CFs (NMCFs) were transfected with miR-425-5p mimics and subsequently stimulated with angiotensin II (Ang II). We found that miR-425-5p levels were significantly downregulated in HF mice and Ang II-treated NMCFs. Notably, fibroblast-specific overexpression of miR-425-5p markedly inhibited the proliferation and differentiation of CFs, thereby alleviating myocardial fibrosis, cardiac hypertrophy and systolic dysfunction. Mechanistically, the cardioprotective actions of miR-425-5p may be achieved by targeting the TGF-β1/Smad signalling. Interestingly, miR-425-5p mimics-treated CFs could also indirectly affect cardiomyocyte hypertrophy in this course. Together, our findings suggest that fibroblast-derived miR-425-5p mitigates TAC-induced HF, highlighting miR-425-5p as a potential diagnostic and therapeutic target for treating HF patients., (© 2024 The Author(s). Journal of Cellular and Molecular Medicine published by Foundation for Cellular and Molecular Medicine and John Wiley & Sons Ltd.)

Background: Leadless cardiac pacemakers (LCPs) are emerging as viable alternatives to conventional transvenous pacemakers (TVPs). This study aimed to systematically compare the postoperative outcomes of LCPs and TVPs based on available published studies., Methods: We conducted a systematic review and meta-analysis of literature comparing outcomes from LCP and TVP implantations. Data analysis was performed using Stata/MP 17.0. The evaluated endpoints included pericardial effusion or perforation, puncture site events, infective endocarditis, lead or device dislodgement, pocket-related complications, tricuspid regurgitation or dysfunction, any infection, increased right ventricle (RV) pacing threshold, embolism, and thrombosis. Aggregated odds ratios (OR) and 95% confidence intervals (CI) were determined. Sensitivity analyses were conducted for heterogeneity if I 2 was >50% or p < 0.01, otherwise, the random-effects model was chosen. Publication bias was analyzed if the number studies exceeded ten., Results: The meta-analysis included 24 observational studies with 78,938 patients, comprising 24,191 with LCP implantation and 54,747 with TVP implantation. The results indicated a significantly lower incidence of lead or device dislodgment (OR = 3.32, 95% CI: 1.91-5.77, p < 0.01), infective endocarditis (OR = 3.62, 95% CI: 3.10-4.24, p < 0.01), and infection (OR = 3.93, 95% CI: 1.67-9.24, p < 0.01) in the LCP group compared to the TVP group. In contrast, incidences of puncture site complications (OR = 0.24, 95% CI: 0.19-0.32, p < 0.01) and pericardial effusion or perforation (OR = 0.33, 95% CI: 0.28-0.39, p < 0.01) were significantly higher in the LCP group., Conclusions: Compared with TVP, LCP implantation is associated with a lower risk of infective endocarditis, lead or device dislodgment, infections, and pocket-related complications. However, LCP implantation carries a higher risk of puncture site complications and pericardial effusion or perforation. These findings underscore the need for careful consideration of patient-specific factors when choosing between LCP and TVP implantation., The Prospero Registration: https://www.crd.york.ac.uk/prospero/ (CRD42023453145)., Competing Interests: The authors declare no conflict of interest., (Copyright: © 2024 The Author(s). Published by IMR Press.)