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Photocatalytic filter plays a key role in VOCs removal and ensuring the long-term durability of photocatalytic filter is essential for increasing their lifespan in real-world industrial application. However, how to unlock the stability of organic supporting materials as photocatalytic filter has not been taken into account. In this work, photocatalyst TiO2 nanoparticles were successfully immobilized on a polyacrylonitrile (PAN) nonwoven using a solvent swelling method, followed by a thermal oxidation treatment. The photocatalytic efficiency of prepared PAN nonwovens in VOCs removal was investigated and the effect of surface treatments and thermal oxidation process on fibers photostability and thermal characteristics were explored. The obtained thermal-oxidized TiO2@PAN nonwoven showed photocatalytic efficiencies of 75% and 92% for the degradation of toluene and formaldehyde gases, respectively, under simulated sunlight. Compared with the TiO2@PAN nonwoven, the photo-induced degradation rate of oxidized-TiO2@PAN nonwoven decreased by 43%, and TGA-DTG results demonstrated a superior thermal stability of the oxidized PAN sample. The findings of this research can facilitate the application of novel PAN-based nonwoven filters in photocatalytic removal of VOCs by providing higher efficiency, improved thermal stability and photostability. [ABSTRACT FROM AUTHOR]

Research has been conducted on Ras-mediated human oncogenesis. The role of the effector proteins in this oncogenesis has been investigated and the differences between the distinct effector pathway to Ras transformation in human and rodent cells have been analyzed.

A subwavelength grating waveguide (GW) consisting of two parallel metallic slabs with periodic corrugations on their inner boundaries is developed to slow down the speed of light at terahertz frequencies. Assisted by a tapered input port, our structure has a transfer efficiency of about 80% over a broad bandwidth and strong confinement in the subwavelength scale. Based on the GW, three graded GWs are designed to demonstrate that the spoof surface plasmon polaritons are slowed down and asymptotically stopped when they tend to the location, where the local cutoff frequency is the same as the frequency of the incident light. [ABSTRACT FROM AUTHOR]

Background and Aims: The cholinergic system is distributed in the nervous system, mediating electrical conduction through acetylcholine (ACh). This study aims to identify whether the heart possesses an intact endogenous cholinergic system and to explore its electrophysiological functions and relationship with arrhythmias in both humans and animals., Methods: The components of the heart's endogenous cholinergic system were identified by a combination of multiple molecular cell biology techniques. The relationship of this system with cardiac electrical conduction and arrhythmias was analysed through electrophysiological techniques., Results: An intact cholinergic system including ACh, ACh transmitter vesicles, ACh transporters, ACh metabolic enzymes, and ACh receptors was identified in both human and mouse ventricular cardiomyocytes (VCs). The key components of the system significantly regulated the conductivity of electrical excitation among VCs. The influence of this system on electrical excitation conduction was further confirmed both in the mice with α4 or α7 nicotinic ACh receptors (nAChRs) knockouts and in the monolayers of human induced pluripotent stem cell-derived cardiomyocytes. Mechanistically, ACh induced an inward current through nAChRs to reduce the minimum threshold current required to generate an action potential in VCs, thereby enhancing the excitability that acts as a prerequisite for electrical conduction. Importantly, defects in this system were associated with fatal ventricular arrhythmias in both patients and mice., Conclusions: This study identifies an integrated cholinergic system inherent to the heart, rather than external nerves that can effectively control cardiac electrical conduction. The discovery reveals arrhythmia mechanisms beyond classical theories and opens new directions for arrhythmia research., (© The Author(s) 2024. Published by Oxford University Press on behalf of the European Society of Cardiology.)

Hydrogen sulfide (H2S) is a gasotransmitter that regulates cardiovascular functions. The present study aimed to determine the protective effect of slow-releasing H2S donor GYY4137 on myocardial ischemia and reperfusion (I/R) injury and to investigate the possible signaling mechanisms involved. Male Sprague-Dawley rats were treated with GYY4137 at 12.5 mg/(kg·day), 25 mg/(kg·day) or 50 mg/(kg·day) intraperitoneally for 7 days. Then, rats were subjected to 30 minutes of left anterior descending coronary artery occlusion followed by reperfusion for 24 hours. We found that GYY4137 increased the cardiac ejection fraction and fractional shortening, reduced the ischemia area, alleviated histological injury and decreased plasma creatine kinase after myocardial I/R. Both H2S concentration in plasma and cystathionine-γ-lyase (CSE) activity in the myocardium were enhanced in the GYY4137 treated groups. GYY4137 also decreased malondialdehyde and myeloperoxidase levels in serum, attenuated superoxide anion level and suppressed phosphorylation of mitogen activated protein kinases in the myocardium after I/R. Meanwhile, GYY4137 increased the expression of Bcl-2 but decreased the expression of Bax, caspase-3 activity and apoptosis in the myocardium. The data suggest that GYY4137 protects against myocardial ischemia and reperfusion injury by attenuating oxidative stress and apoptosis.