The selective electrochemical CO2 reduction (ECR) to CO in aqueous electrolytes has gained significant interest in recent years due to its capability to mitigate the environmental issues associated with CO2 emission and to convert renewable energy such as wind and solar power into chemical energy as well as its potential to realize the commercial use of CO2. In view of the thermodynamic stability and kinetic inertness of CO2 molecules, the exploitation of active, selective, and stable catalysts for the ECR to CO is crucial to promote the reaction efficiency. Indeed, plenty of electrocatalysts for the selective ECR to CO have been explored, of which Ag is known as the most promising electrocatalyst for large‐scale ECR to CO due to several competitive advantages including high catalytic performance, low price, and rich reserves compared with other metal counterparts. To provide useful guidelines for the further development of efficient catalysts for the ECR to CO, a comprehensive summary of the recent progress of Ag‐based electrocatalysts is presented in this Review. Different modification strategies of Ag‐based electrocatalysts are highlighted, including exposure of crystal facets, tuning of morphology and size, introduction of support materials, alloying with other metals, and surface modification with functional groups. The reaction mechanisms involved in these different modification strategies of Ag‐based electrocatalysts are also discussed. Finally, the prospects for the development of next‐generation Ag‐based electrocatalysts are proposed in an effort to facilitate the industrialization of ECR to CO.

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Here, a g-CN nanosheet modified microwell array providing enhanced electrochemiluminescence (ECL) and better visible sensitivity was prepared to simultaneously analyze total (membrane and intracellular) cholesterol at single cells. The detection limit for ECL visualization of hydrogen peroxide at microwell array was improved to be 500 nM that guaranteed the detection of low concentration cholesterol at single cells in parallel. To achieve single cell cholesterol analysis, the individual cells cultured at the microwell array were exposed to cholesterol oxidase generating hydrogen peroxide for luminescence analysis of membrane cholesterol, and then treated with triton X-100, cholesterol esterase, and cholesterol oxidase to produce hydrogen peroxide from intracellular cholesterol for luminescence determination. The observation of the luminescence spots at microwells in these two steps confirmed the codetection of membrane and intracellular cholesterol at single cells. The inhibition of intracellular acyl-coA/cholesterol acyltransferase (ACAT) resulted in less intracellular cholesterol storage (less luminescence) and more membrane cholesterol (more luminescence). The correlation of the luminescence intensity with the amount of cholesterol confirmed that our assay could simultaneously monitor membrane and intracellular cholesterol pools at different cellular states, which should offer more information for the study of cholesterol-related pathways at single cells.

Rice is a model plant species for the study of cellulose biosynthesis. We isolated a mutant, S1-24, from ethyl methanesulfonate (EMS)-treated plants of the japonica rice cultivar, Nipponbare. The mutant exhibited brittle culms and other pleiotropic phenotypes such as dwarfism and partial sterility. The brittle culms resulted from reduced mechanical strength due to a defect in thickening of the sclerenchyma cell wall and reduced cellulose content in the culms of the S1-24 mutant. Map-based gene cloning and a complementation assay showed that phenotypes of the S1-24 mutant were caused by a recessive point mutation in the OsCESA7 gene, which encodes cellulose synthase A subunit 7. The missense mutation changed the highly conserved C40 to Y in the zinc finger domain. The OsCESA7 gene is expressed predominantly in the culm at the mature stage, particularly in mechanical tissues such as vascular bundles and sclerenchyma cells, consistent with the brittle phenotype in the culm. These results indicate that OsCESA7 plays an important role in cellulose biosynthesis and plant growth.