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Nitrogen dioxide (NO2), even at parts-per-billion (ppb) concentrations, can greatly threaten human health. Two-dimensional (2D) nonlayered metal oxides demonstrate the strong potential of detecting ppb-level NO2 gas at low temperatures or room temperature with unique selectivity, owing to their physisorption behaviors of NO2 gas molecules as well as abundant active sites based on dangling bonds and defects. In this work, we reveal the ppb-level NO2 detection capability of 2D nonlayered FeOOH as a derivative of 2D metal oxides, which are synthesized from a facile water-dissolvable template with abundant surface hydroxide groups acting as active sites of NO2 adsorption. 2D FeOOH exhibits large lateral dimensions of ∼1–1.5 μm with thicknesses of ∼4–5 nm. An optical energy band gap of 2.2 eV is found, which is suitable for visible-light-driven optoelectronic NO2 gas sensing. An impressive response factor of 36 for 37.5 ppb NO2 is achieved at 160 °C under blue light excitation with full reversibility, excellent long-term stability in months, unique selectivity, and a detection limit of 0.38 ppb, which is significantly improved over those of ppb-level NO2 sensors based on metal oxides. This work reveals 2D nonlayered metal oxyhydroxides as a group of suitable candidates for future high-performance NO2 gas sensors. [ABSTRACT FROM AUTHOR]

Type-II superlattices have recently emerged as a focal point in long-wavelength infrared (LWIR) detection, showcasing remarkable potential across various applications. In this work, we have conducted a theoretical investigation into the band structure and optical properties of 14/7 monolayers (ML) InAs/GaSb superlattices (SLs), employing density functional theory. Our findings indicate that the energy gap of these SLs is determined to be 0.111 eV through energy band structure analysis using the Heyd–Scuseria–Ernzerhof method. Moreover, we have designed a resonant cavity-enhanced "Φ" structure for the 14/7 ML InAs/GaSb SLs infrared detector. This innovative design markedly enhances absorption efficiency, increasing it from 16.48% to an impressive 76.35% at the 11.2 μm wavelength. Further analysis includes a detailed examination of the electric field distribution within this structure and a comprehensive examination of the enhanced plasmonic resonator's perfect absorption phenomenon. The results from these analyses underscore the exceptional absorption capabilities of our resonant cavity-enhanced infrared detector, indicating its potential for significant applications in LWIR SLs focal plane. [ABSTRACT FROM AUTHOR]

Chronic kidney diseases (CKD) is a serious threat to people's health with renal fibrosis as the major pathological feature. The absent in melanoma 2 (AIM2) has recently been proposed to play a critical role in CKD. Emodin is a major bioactive compound from rhubarb, which is widely used for clinical treatment of renal disease. The aim of this study is to elucidate the effect of emodin on unilateral ureteral obstruction (UUO) model mice and its association with the AIM2 inflammasome. In this study, we established the UUO-induced mice renal interstitial fibrosis in vivo and bone marrow-derived macrophages (BMDMs) model in vitro. The BUN, SCr, TNF-α, IL-1β in serum were examined. The degree of renal damage and fibrosis were determined by histological assessment. Immunofluorescence, western blot, and Co-IP were used to determine the mechanisms of emodin against CKD. Emodin could improve UUO-induced abnormal renal function and histopathological abnormalities. It could also ameliorate renal fibrosis, evidenced by inhibiting the expression of α-SMA, TGF-β1, FN, and collagen I. Mechanistically, emodin significantly suppressed AIM2 inflammasome as well as its components including ASC, cleaved caspase-1, and IL-1β both in vivo and in vitro. Further studies demonstrated that emodin inhibited K27-linked polyubiquitination of AIM2 by targeting on K64 sites of the lysine residues. In summary, emodin could hinder the activation of AIM2 inflammasome in UUO model mice through K27-linked polyubiquitination to reduce renal fibrosis. Emodin is a possible therapeutic option for CKD treatment., (© 2024 John Wiley & Sons Ltd.)

The mid-wave multispectral detector combines the traditional spectrometer and infrared detector technologies to provide image information and spectral information at the same time, which has an important role in both civil and military fields. To solve the working band limitation and low energy utilization, this paper presents an integrated superlattice mid-wave multispectral hypersurface detector that can be used for computational multispectroscopy for the first time, which consists of photonic crystal (PC) plates of GaSb material, and uses PC microstructures to modulate the incident spectra, which can be used to reconstruct incident signals with computational multispectroscopy methods. In this paper, the finite difference time domain method (FDTD) is used to simulate the structural parameters of different PCs, and finally calculate the correlation coefficients of the transmission spectra of the different structures as well as the energy utilization rate. The simulation results show that the optimized structures have unique response curves and rich spectral features, with the average value of Pearson correlation coefficients (PCCs) < 0.3 and energy utilization >50%. It can be utilized in various fields, including astronomical remote sensing, medical diagnostics, and military reconnaissance.