Controlling the size of Au nanoparticles (NPs) and their interaction with the oxide support is important for their catalytic performance in chemical reactions, such as CO oxidation and water-gas shift. It is known that the oxygen vacancies at the surface of support oxides form strong chemical bonding with the Au NPs and inhibit their coarsening and deactivation. The resulting Au/oxygen vacancy interface also acts as an active site for oxidation reactions. Hence, small Au NPs are needed to increase the density of the Au/oxide interface. A dynamic way to control the size of the Au NPs on an oxide support is desirable but has been missing in the field. Here, we demonstrate an electrochemical method to control the size of the Au NPs by controlling the surface oxygen vacancy concentration of the support oxide. Oxides with different reducibilities, LaCaMnO and PrCeO, are used as model support oxides. By applying the electrochemical potential, we achieve a wide range of effective oxygen pressures, pO (10-10 atm), in the support oxides. Applying the cathodic potential creates a high concentration of oxygen vacancies and forms finely distributed Au NPs with sizes of 7-13 nm at 700-770 °C in 10 min, while the anodic potential oxidizes the surface and increases the size of the Au NPs. The onset cathodic potential required to create small Au NPs depends strongly on the reducibility of the support oxide. The Au NPs did not undergo sintering even at 700-770 °C under the cathodic potential and also were stable in catalytically relevant conditions without potential.
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http://dx.doi.org/10.1021/jacs.2c08422 | DOI Listing |
J Cardiothorac Vasc Anesth
January 2025
Department of Anesthesia, Critical Care, and Pain Medicine, Massachusetts General Hospital, Boston, MA.
Vasoplegia is a pathophysiologic state of hypotension in the setting of normal or high cardiac output and low systemic vascular resistance despite euvolemia and high-dose vasoconstrictors. Vasoplegia in heart, lung, or liver transplantation is of particular interest because it is common (approximately 29%, 28%, and 11%, respectively), is associated with adverse outcomes, and because the agents used to treat vasoplegia can affect immunosuppressive and other drug metabolism. This narrative review discusses the pathophysiology, risk factors, and treatment of vasoplegia in patients undergoing heart, lung, and liver transplantation.
View Article and Find Full Text PDFAm J Chin Med
January 2025
Basic Medical School, Gansu University of Chinese Medicine, Lanzhou 730000, P. R. China.
Oxidative stress represents a pivotal mechanism in the pathogenesis of numerous chronic diseases. The Kelch-like ECH-associated protein 1-transcription factor NF-E2 p45-related factor 2 (KEAP1-NRF2) pathway plays a crucial role in maintaining redox homeostasis and regulating a multitude of biological processes such as inflammation, protein homeostasis, and metabolic homeostasis. In this paper, we present the findings of recent studies on the KEAP1-NRF2 pathway, which have revealed that it is aberrantly regulated and induces oxidative stress injury in a variety of diseases such as neurodegenerative diseases, cardiovascular diseases, metabolic diseases, respiratory diseases, digestive diseases, and cancer.
View Article and Find Full Text PDFAm J Chin Med
January 2025
School of Pharmacy, Nantong University, 9 Seyuan Road, Nantong 226019, P. R. China.
Ginkgolic acids (GAs) are distinctive secondary metabolites of () primarily found in its leaves and seeds, with the highest concentration located in the exotesta. GAs are classified as long-chain phenolic compounds, and exhibit structural similarities to lignoceric acid. Their structural diversity arises from variations in the length of side chains and their number of double bonds, resulting in six distinct forms within extracts (GBE).
View Article and Find Full Text PDFToxicology
January 2025
Toxicology and Pharmacology Laboratory, Department of Biotechnology, Faculty of Science and Humanities, SRM Institute of Science and Technology, Kattankulathur, 603203, Chengalpattu District, Tamil Nadu, India. Electronic address:
Aniline Blue is a synthetic dye extensively used in various industries, including textiles, plastics, and biological research due to its effective staining properties. However, its environmental and health impacts, particularly its neurotoxic effects, are poorly understood. While the dye has been associated with carcinogenicity and organ toxicity, the neurobehavioral consequences of Aniline Blue exposure remain underexplored.
View Article and Find Full Text PDFBiochimie
January 2025
Laboratory of Biochemistry and Molecular Neuropharmacology (LABIONEM), Graduate Program in Biochemistry and Bioprospecting (PPGBBio), Chemical, Pharmaceutical, and Food Sciences Center (CCQFA), Federal University of Pelotas (UFPel), 96010-900 RS, Brazil. Electronic address:
Oxidative stress arises from an imbalance between reactive species (RS) production and the antioxidant defense, increasing the brain susceptibility to neurodegenerative and psychiatric diseases. Besides, changes in the expression or activity of neurotransmitter metabolism enzymes, such as monoamine oxidases (MAO), are also associated with mental disorders, including depression. Considering this, antioxidant and MAO-A activity inhibitory potential of six 2,3-chalcogenodihydrobenzofurans (2,3-DHBF) was investigated through in vitro and in silico tests.
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