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Perovskite‐based light‐emitting diodes (PeLEDs) are now approaching the upper limits of external quantum efficiency (EQE); however, their application is currently limited by reliance on lead and by inadequate color purity. The Rec. 2020 requires Commission Internationale de l'Eclairage coordinates of (0.708, 0.292) for red emitters, but present‐day perovskite devices only achieve (0.71, 0.28). Here, lead‐free PeLEDs are reported with color coordinates of (0.706, 0.294)—the highest purity reported among red PeLEDs. The variation of the emission spectrum is also evaluated as a function of temperature and applied potential, finding that emission redshifts by <3 nm under low temperature and by <0.3 nm V−1 with operating voltage. The prominent oxidation pathway of Sn is identified and this is suppressed with the aid of H3PO2. This strategy prevents the oxidation of the constituent precursors, through both its moderate reducing properties and through its forming complexes with the perovskite that increase the energetic barrier toward Sn oxidation. The H3PO2 additionally seeds crystal growth during film formation, improving film quality. PeLEDs are reported with an EQE of 0.3% and a brightness of 70 cd m−2; this is the record among reported red‐emitting, lead‐free PeLEDs. Sn‐based perovskite light‐emitting diodes with ultra‐high red color purity, a brightness of 70 cd m−2, and 24 nm linewidth are prepared. The devices show excellent color stability under different temperatures, power, and operating voltage. Based on the oxidation pathway of Sn, H3PO2 is chosen to suppress the oxidation of Sn2+ and slow down the crystal growth, simultaneously.

Hyperbolic polaritons have drawn great attention in nanoscale light manipulation due to their unique properties. Currently, most studies focus on natural hyperbolic phonon materials in the mid-infrared, limiting their application in the visible to near-infrared range. Here, we present a work on broadband near-infrared hyperbolic plasmon polaritons in a van der Waals material MoOCl 2 by a perturbation-free direct imaging technique of photoemission electron microscopy. In particular, the hyperbolic polariton behavior has been dynamically tailored and manipulated by wavelength, polarization, interlayer twist, and artificial structure, providing a reconfigurable platform for nanophotonic applications. Notably, the full iso-frequency contours can be reconstructed via polarization-selective excitations. Our work has contributed to hyperbolic materials in the broadband near-infrared with MoOCl 2 , and has revealed PEEM to be an ideal method for studying hyperbolic plasmon polaritons at the space-time limit. Materials with opposite signs of permittivity along the two orthogonal directions can support hyperbolic polaritons. Here, the authors demonstrate tunable broadband near-infrared hyperbolic plasmon polaritons in MoOCl 2 .

Low-loss dielectric modes are important features and functional bases of fundamental optical components in on-chip optical devices. However, dielectric near-field modes are challenging to reveal with high spatiotemporal resolution and fast direct imaging. Herein, we present a method to address this issue by applying time-resolved photoemission electron microscopy to a low-dimensional wide-bandgap semiconductor, hexagonal boron nitride (hBN). Taking a low-loss dielectric planar waveguide as a fundamental structure, static vector near-field vortices with different topological charges and the spatiotemporal evolution of waveguide modes are directly revealed. With the lowest-order vortex structure, strong nanofocusing in real space is realized, while near-vertical photoemission in momentum space and narrow spread in energy space are simultaneously observed due to the atomically flat surface of hBN and the small photoemission horizon set by the limited photon energies. Our approach provides a strategy for the realization of flat photoemission emitters. The application of time-resolved photoemission electron microscopy (TR-PEEM) to non-conducting materials is challenging. Here, the authors report the TR-PEEM characterization of near-field dielectric modes and photoemission properties of insulating hexagonal boron nitride structures on indium tin oxide/glass substrates.

Atrial fibrillation (AF) represents the commonly occurring cardiac arrhythmia and the main factor leading to stroke and heart failure. Hydrogen (H 2 ) is a gaseous signaling molecule that has the effects of anti-inflammation and antioxidation. Our study provides evidence that hydrogen decreases susceptibility to AngII-mediated AF together with atrial fibrosis. Following continuous AngII administration for a 28-day period, AngII+H 2 treated rats showed decreased susceptibility to AF, a decrease in atrial fibrosis, a decrease in ROS in atrial myocytes, an inhibition of NLRP3 inflammasome activation, an improvement in electrical remodeling, and an inhibition of proliferation and migration of cardiac fibroblasts. We further found that hydrogen regulates the activation of inflammasome and thus improves Ca 2+ handling and IKAch and IKur by inhibiting the activity of NOX4 in vivo. In addition, hydrogen was involved in AngII-mediated atrial fibrosis through inhibiting TGF-β1/Smad2/3 pathway through suppressing TGF-β1 activation and secretion in vivo. Our findings suggest that hydrogen is important for preventing and treating AngII-mediated AF and atrial fibrosis, suggesting that hydrogen could be used as the candidate way to prevent and treat AF.

The on-chip measurement of polarization states plays an increasingly crucial role in modern sensing and imaging applications. While high-performance monolithic linearly polarized photodetectors have been extensively studied, integrated circularly polarized light (CPL) photodetectors are still hindered by inadequate discrimination capability. This study presents a broadband CPL photodetector utilizing achiral all-dielectric nanostructures, achieving an impressive discrimination ratio of ~107 at a wavelength of 405 nm. Our device shows outstanding CPL discrimination capability across the visible band without requiring intensity calibration. It functions based on the CPL-dependent near-field modes within achiral structures: under left or right CPL illumination, distinct near-field modes are excited, resulting in asymmetric irradiation of the two electrodes and generating a photovoltage with directions determined by the chirality of the incident light field. The proposed design strategy facilitates ultra-compact CPL detection across diverse materials, structures, and spectral ranges, presenting a novel avenue for achieving high-performance monolithic CPL detection.Based on the chiral-dependent near-field modes within dielectric achiral structures, a broadband circularly polarized light photodetector with an impressive discrimination ratio is presented.

Background Pentamidine has been reported to have many pharmacological effects including anti- protozoal, anti-inflammatory, and anti-tumor activities. The aim of this study is to investigate the potential therapeutic role of Pentamidine and molecular mechanisms of Pentamidine on PI3K/AKT signaling pathway underlying the anti-tumor properties in endometrial cancer. Methods Our study was carried out in the central laboratory of Harbin Medical University from 2019 to 2021. Human endometrial cancer cell lines Ishikawa and HEC-1A were treated with Pentamidine. The proliferation ability of cells was investigated by MTS and colony formation assays. The cell cycle distribution was detected by flow cytometry. Cell migration and invasion were analyzed by using the wound healing assay and Transwell assay. Western blotting was performed to measure the levels of AKT, p-AKT, MMP-2, and MMP-9. Results Our results revealed that treatment of Pentamidine inhibited proliferation, migration and invasion of Ishikawa and HEC-1A endometrial cancer cells. Mechanistic investigation showed that Pentamidine inhibited PI3K/AKT signaling pathway and also reduced the expression of MMP-2 and MMP-9. In addition, co-treatment with PI3K kinase inhibitor LY294002 and Pentamidine leaded to increased repression of cell viability and the protein expression of p-AKT in Ishikawa cells. Conclusions Pentamidine suppresses PI3K/AKT signaling pathway, and inhibits proliferation, migration and invasion of EC cells. These findings suggested that Pentamidine might be a potential candidate for treating EC through PI3K/AKT pathway.

Background/Aims: Selenium (Se) deficiency can lead to several cardiac diseases, including Keshan disease in humans, mulberry heart disease in pigs and cardiac injury in chickens. MicroRNAs have been a research focus in recent years and have been shown to participate in a new avenue of cell death-autophagy, which can play a significant role in several types of heart disease. Methods: MicroRNAome analysis showed that the expression of miR-2954 was increased in the myocardium of selenium-deficient chickens, and PI3K was predicted to be the target gene. The target relationship between miR-2954 and PI3K was verified with a double fluorescence enzyme assay and RNA Protein Interaction Prediction and molecular docking software. qRT-PCR and western blotting were used to detect the expression of PI3K and related pathway components in selenium-deficient chickens and miR-2954 knockout/overexpression cardiomyocytes. Results: In this study, we observed that miR-2954 overexpression led to inhibition of PI3K pathway in vivo and in vitroled to inhibition of the PI3K pathway in vivo and in vitro. Conclusion: The expression of miR-2954 was increased in selenium-deficient myocardium, whereas overexpression of miR-2954 led to autophagy and apoptosis of myocardial cells during cardiac injury through regulation of the PI3K pathway; whether this phenomenon is a self-protection mechanism of the organism or damage caused by miR-2954 requires further study. Our findings provides new insight apoptosis in cardiomyocytes; additionally, we aim to provide a new direction for the diagnosis and targeted treatment of myocardial diseases.

Background/Aims: To study the effect of inhaling hydrogen gas on myocardial ischemic/reperfusion(I/R) injury in rats. Methods: Seventy male Wistar albino rats were divided into five groups at random as the sham group (Sham). The I/R group (I/R), The ischemic postconditioning group (IPo), The I/R plus hydrogen group (IH 2 ) and the ischemic postconditioning plus hydrogen group (IPoH 2 ). The Sham group was without coronary occlusion. In I/R group, Ischemic/reperfusion injury was induced by coronary occlusion for 1 hour. Followed by 2 hours of reperfusion. In the IPo and IPoH2 group, four cycles of 1 min reperfusion/1 min ischemia was given at the end of 1 hour coronary occlusion. While 2% hydrogen was administered by inhalation 5 min before reperfusion till 2 hours after reperfusion in both the IPoH2 and IH2 group. The heart and blood samples were harvested at the end of the surgical protocol. Then the myocardium cell endoplasmic reticulum(ER) stress and autophagy was observed by electron microscope. In addition, the cardiac ER stress and autophagy related proteins expression were detected by Western blotting analysis. Results: Both inhaling 2% hydrogen and ischemic postconditioning treatment reduced the ischemic size and serum troponin I level in rats with I/R injury, and inhaling hydrogen showed a more curative effect compared with ischemic postconditioning treatment. Meanwhile inhaling hydrogen showed a better protective effect in attenuating tissue reactive oxygen species. Malondialdehyde levels and immunoreactivities against 8-hydroxy-2’-deoxyguanosine and inhibiting cardiac endoplasmic reticulum stress and down-regulating autophagy as compared with ischemic postconditioning treatment. Conclusion: These results revealed a better protective effect of hydrogen on myocardial ischemic/reperfusion injury in rats by attenuating endoplasmic reticulum stress and down-regulating autophagy compared with ischemic postconditioning treatment.

Doxorubicin (DOX) remains the most effective anticancer agent which is widely used in several adult and pediatric cancers, but its application is limited for its cardiotoxicity and hepatotoxicity. Hydrogen, as a selective antioxidant, is a promising potential therapeutic option for many diseases. In this study, we found that intraperitoneal injection of hydrogen-rich saline (H2 saline) ameliorated the mortality, cardiac dysfunction, and histopathological changes caused by DOX in rats. Meanwhile, serum brain natriuretic peptide (BNP), aspartate transaminase (AST), alanine transaminase (ALT), albumin (ALB), tissue reactive oxygen species (ROS), and malondialdehyde (MDA) levels were also attenuated after H2 saline treatment. What is more, we further demonstrated that H2 saline treatment could inhibit cardiac and hepatic inflammation and apoptosis relative proteins expressions by western blotting test. In conclusion, our results revealed a protective effect of H2 saline on DOX-induced cardiotoxicity and hepatotoxicity in rats by inhibiting inflammation and apoptosis.

Solid films of colloidal quantum dots show promise in the manufacture of photodetectors and solar cells. These devices require high yields of photogenerated charges and high carrier mobilities, which are difficult to achieve in quantum-dot films owing to a strong electron–hole interaction and quantum confinement. Here, we show that the quantum yield of photogenerated charges in strongly coupled PbSe quantum-dot films is unity over a large temperature range. At high photoexcitation density, a transition takes place from hopping between localized states to band-like transport. These strongly coupled quantum-dot films have electrical properties that approach those of crystalline bulk semiconductors, while retaining the size tunability and cheap processing properties of colloidal quantum dots. Thin films of strongly coupled PbSe quantum dots exhibit light-induced charge generation with a yield of one electron and one hole per photon over a wide temperature range.