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Autophagy, a conserved cellular recycling process, plays a crucial role in maintaining homeostasis under stress conditions. It also regulates the development and virulence of numerous filamentous fungi. In this study, we investigated the specific function of ATG8, a reliable autophagic marker, in the opportunistic pathogen Aspergillus flavus. To investigate the role of atg8 in A. flavus, the deletion and complemented mutants of atg8 were generated according to the homologous recombination principle. Deletion of atg8 showed a significant decrease in conidiation, spore germination, and sclerotia formation compared to the WT and atg8C strains. Additionally, aflatoxin production was found severely impaired in the ∆atg8 mutant. The stress assays demonstrated that ATG8 was important for A. flavus response to oxidative stress. The fluorescence microscopy showed increased levels of reactive oxygen species in the ∆atg8 mutant cells, and the transcriptional result also indicated that genes related to the antioxidant system were significantly reduced in the ∆atg8 mutant. We further found that ATG8 participated in regulating the pathogenicity of A. flavus on crop seeds. These results revealed the biological role of ATG8 in A. flavus, which might provide a potential target for the control of A. flavus and AFB1 biosynthesis. [ABSTRACT FROM AUTHOR]

Plant miRNAs are a class of noncoding RNA with a length of 21–24 nt that play an important role in plant responses to biotic and abiotic stresses. Bacterial blight (BB) caused by Xanthomonas oryzae pv. oryzae (Xoo) is one of the most serious bacterial diseases in rice. Our previous work showed that osa-miR2118b/n was induced by Xoo infection. However, the biological function of miR2118 has not yet been characterized in experiments. Herein, we constructed MIR2118b OE, as well as single and double mutants of MIR2118b/n using CRISPR/Cas9. Further results showed that osa-MIR2118b OE plants exhibited longer lesion lengths than the wild type after Xoo inoculation, while MIR2118 CRISPR plants exhibited shorter lesion lengths than the wild type after Xoo inoculation. Co-transformation experiments in rice protoplasts indicated that osa-miR2118 negatively regulated the transcripts of three nucleotide-binding sites and leucine-rich repeat (NLR) genes (LOC_Os08g42700.1, LOC_Os01g05600.1, and LOC_Os12g37290.1) which are predicted target genes of miR2118, but not the mutated NLR genes with a 3 bp insertion at the center of the binding sites. The transcriptional level of the three NLR genes was reversed relative to osa-miR2118 in the MIR2118b OE and MIR2118b CRISPR plants. The above results demonstrate that osa-miR2118b/n negatively regulates the resistance to bacterial blight through negatively regulating several NLR genes. [ABSTRACT FROM AUTHOR]

H2/CO2 fuel cells are important devices that convert CO2 into CH4 while generating electricity at mild temperatures. Anhydrous ruthenium oxide (RuO2) on carbon nanotubes (CNT) as a cathode catalyst causes CO2 methanation, but the methane production rate needs to be improved. In this paper, a core–shell structure of CNT@hydrous RuO2 was fabricated by a simple sol–gel method. Unlike anhydrous RuO2, which is a single electronic conductor, CNT@hydrous RuO2 is a proton–electron mixed conductive material. Therefore, protons transfer not only in thepolybenzimidazole (PBI) film but also in the catalyst layer with the assistance of crystalline water in hydrous RuO2. CO2 methanation involving a reaction of multiple protons and electrons can be accelerated. The methane generation rate of CNT@hydrous RuO2 reached 331.2 μmol gcat−1 h−1 at 190 °C which is 3 times higher than that of anhydrous RuO2. This research result provides an effective strategy for the catalytic reaction of multiple proton–electron transfers. [ABSTRACT FROM AUTHOR]

In this paper, a novel sliding mode fault tolerant control method is presented for aircraft engine systems with uncertainties and disturbances on the basis of adaptive diagnostic observer. By taking both sensors faults and actuators faults into account, the general model of aircraft engine control systems which is subjected to uncertainties and disturbances, is considered. Then, the corresponding augmented dynamic model is established in order to facilitate the fault diagnosis and fault tolerant controller design. Next, a suitable detection observer is designed to detect the faults effectively. Through creating an adaptive diagnostic observer and based on sliding mode strategy, the sliding mode fault tolerant controller is constructed. Robust stabilization is discussed and the closed-loop system can be stabilized robustly. It is also proven that the adaptive diagnostic observer output errors and the estimations of faults converge to a set exponentially, and the converge rate greater than some value which can be adjusted by choosing designable parameters properly. The simulation on a twin-shaft aircraft engine verifies the applicability of the proposed fault tolerant control method. [ABSTRACT FROM AUTHOR]

A single-site copper complex, [Cu(TMC)(H2O)](NO3)2 (1, TMC = 1,4,8,11-tetramethyl-1,4,8,11-tetraazacyclotetradecane), was found to be the most active copper-based catalyst towards electrocatalytic water oxidation in neutral aqueous solution. Complex 1 leads to a cathodic shift of approximately 200 mV in potential to reach a current density of 1 mA cm−2 in comparison with that of the previously reported dinuclear copper complex under the same conditions. Upon immobilization of complex 1 on carbon cloth, it shows greatly improved activity than other copper-based WOCs including CuOx and Cu2+. [ABSTRACT FROM AUTHOR]

A cyanide-bridged Fe Co double zigzag chain, {[Fe(bipy)(CN)]Co(btab)} [bipy=2,2′-bipyridine, btab=4,4′-(1,3-phenylene)-bis-4 H-1,2,4-triazole] ( 1), was obtained with tetracyanometalate precursors and Co ions. The chains were further linked by the ditopic btab ligands to a layer. Magnetic property studies demonstrate that 1 shows both metamagnetism with a critical field H =400 Oe and single-chain magnet behavior. [ABSTRACT FROM AUTHOR]