Impaired GPX4 activity elicits ferroptosis in alveolar type II cells promoting PHMG-induced pulmonary fibrosis development.

Inhaling polyhexamethylene guanidine (PHMG) aerosol, a broad-spectrum disinfectant, can lead to severe pulmonary fibrosis. Ferroptosis, a form of programmed cell death triggered by iron-dependent lipid peroxidation, is believed to play a role in the chemical-induced pulmonary injury. This study aimed to investigate the mechanism of ferroptosis in the progression of PHMG-induced pulmonary fibrosis. C57BL/6 J mice and the alveolar type II cell line MLE-12 were used to evaluate the toxicity of PHMG in vivo and in vitro, respectively. The findings indicated that iron deposition was observed in PHMG induced pulmonary fibrosis mouse model and ferroptosis related genes have changed after 8 weeks PHMG exposure. Additionally, there were disturbances in the antioxidant system and mitochondrial damage in MLE-12 cells following a 12-hour treatment with PHMG. Furthermore, the study observed an increase in lipid peroxidation and a decrease in GPX4 activity in MLE-12 cells after exposure to PHMG. Moreover, pretreatment with the ferroptosis inhibitors Ferrostatin-1 (Fer-1) and Liproxstatin-1 (Lip-1) not only restored the antioxidant system and GPX4 activity but also mitigated lipid peroxidation. Current data exhibit the role of ferroptosis pathway in PHMG-induced pulmonary fibrosis and provide a potential target for future treatment.

Electric Field Detection System Based on Denoising Algorithm and High-Speed Motion Platform.

Effective denoising can ensure fast and accurate target detection. This paper presents an electric field measurement system based on a high-speed motion platform, which was built to analyze the characteristics of low frequency electric field noise. An offshore test has shown that it is possible to detect a low-frequency electric field using a high-speed motion platform. Low frequency electric field noise was then collected to analyze its characteristics in terms of time and frequency domains. Based on the noise characteristics, complete ensemble empirical mode decomposition with adaptive noise (ICEEMDAN) was improved and combined with an adaptive threshold algorithm for denoising and reconstructing target containing noise signals. As revealed in the results, the proposed algorithm achieved highly effective denoising to overcome the line spectrum detection failure resulting from a high-speed motion platform. The detection range had also been improved from the original 853 m to 1306 m, a 53.1% increase.

Boron-terminated diamond (100) surfaces with promising structural and electronic properties.

Boron (B) termination plays an important role in determining the surface properties of the diamond (100) surface. A recent study [J. Mater. Chem. C, 2019, 7, 9756] reported a stable surface structure with one B atom per carbon atom based on high-symmetry adsorption sites having a negative electron affinity (EA) property. In this work, using the global structure prediction method and first-principle calculations, four kinds of B-diamond (100) surfaces with 0.5 monolayers (0.5 ML, one B atom per two carbon atoms), and 1 ML-α, 1 ML-ß, and 1 ML-γ (one B atom per carbon atom with three types of configurations known as α, ß, and γ) coverages obtained are dynamically and thermally stable. The calculations reveal that B termination effectively modulates the EA of the diamond (100) surface. The 0.5 ML coverage has a small positive EA of 0.24 eV, while the latter three 1 ML coverages with different configurations possess the negative EA of -1.27, -1.25, and -0.76 eV, respectively, due to the difference in charge accumulation and surface dipole moment. Moreover, the B-related surface states are introduced into the bandgap of the bulk diamond, and the band dispersions of the surface states are small (large) in 0.5 ML and 1 ML-γ (1 ML-α and 1 ML-ß) as a consequence of the different arrangements of B atoms and the bond lengths between B atoms on the surface. Our finding provides theoretical guidance for the design and fabrication of B-diamond-based electronic devices.

Conductive interpenetrating network organohydrogels of gellan gum/polypyrrole with weather-tolerance, piezoresistive sensing and shape-memory capability.

To develop ecofriendly multifunctional gel materials for sustainable flexible electronic devices, composite organohydrogels of gellan gum (GG) and polypyrrole (PPy) with an interpenetrating network structure (IPN-GG/PPy organohydrogels) were developed first time, through fabrication of GG organohydrogels followed by in-situ oxidation polymerization of pyrrole inside. Combination of water with glycerol can not only impart environment-stability to GG hydrogels but promote the mechanics remarkably, with the compressive strength amplified by 1250 % from 0.02 to 0.27 MPa. Incorporation of PPy confers electrical conductivity to the GG organohydrogel as well as promoting the mechanical performance further. The maximum conductivity of the IPN-GG/PPy organohydrogels reached 1.2 mS/cm at 25 °C, and retained at 0.6 mS/cm under -20 °C and 0.56 mS/cm after 7 days' exposure in 25 °C and 60 % RH. The compression strength of that with the maximum conductivity increases by 170 % from 0.27 to 0.73 MPa. The excellent conductivity and mechanical properties endow the IPN-GG/PPy organohydrogels good piezoresistive strain/pressure sensing behavior. Moreover, the thermo-reversible GG network bestows them shape-memory capability. The multifunctionality and intrinsic eco-friendliness is favorable for sustainable application in fields such as flexible electronics, soft robotics and artificial intelligence, competent in motion recognition, physiological signal monitoring, intelligent actuation.

A Nanometer-Sized Graphite/Boron-Doped Diamond Electrochemical Sensor for Sensitive Detection of Acetaminophen.

A boron-doped diamond (BDD) has been widely used as an outstanding electrode for constructing high-performance electrochemical biosensors. In this paper, we fabricated a novel electrode combined of nanometer-sized graphite-BDD film (NG-BDD) by chemical vapor deposition. The nanometer-sized graphite (NG) is formed on the (111) facet of BDD via converting an sp3 diamond structure to an sp2 graphitic phase at high temperature in boron-rich ambient. The electrode was characterized by means of scanning electron microscopy, Raman spectroscopy, X-ray diffraction, and X-ray photoelectron spectroscopy. This NG-BDD was performed as an electrode of electrochemical biosensor to detect trace acetaminophen (APAP) accurately. Cyclic voltammetry and differential normal pulse voltammetry are used to investigate the overall performance of the electrochemical device. The sensor has a linear electrochemical response to APAP in the concentration range of 0.02-50 µM, and the detection limit is estimated to be as low as 5 nM. The research has resulted in a solution of constructing a reusable NG-BDD sensor to detect APAP with stability and show potential in extensive application.

Structural and electronic properties of c-BN (111) surface with hydrogen/fluorine functionalization and nitrogen-based small-molecule adsorption.

Using first-principles density functional theory calculations, we systematically investigate the structural and electrical properties of pure, hydrogen (H) and fluorine (F) functionalized polar (111) cubic boron nitride (c-BN) surface. In the absence of surface functionalization, the reconstructed B-terminated surface is energetically preferable. The hydrogenation is favorable for stabilizing N- and B-terminated surfaces, while the fluorination leads to the stable unreconstructed B-terminated structure due to strong site preference of F atoms. The reconstructed c-BN surface has magnetic characteristic, and the spin density distributions are mainly localized around the interlayer weak B-B bonds. The unreconstructed structures are nonmagnetic. Meantime, the adsorption behavior of nitric oxide (NO) and ammonia (NH3) molecules are investigated on the reconstructed c-BN surface. It is found that the adsorption of NO has a considerable effect on the energy levels near the Fermi level, while the energy levels of NH3 are located at the deep energy level below the Fermi level. Our theoretical results are helpful for understanding experimental phenomenon in practical applications and designing novel c-BN based molecule sensors.