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The effect of graphene oxide with different reduction degrees on the photocatalytic efficiency of titanium dioxide‐graphene (TiO2‐G) composites has not been systematically studied. In this paper, titanium dioxide‐partially reduced graphene oxide (TiO2‐PRGO) nanocomposites were prepared by a modified one‐step solvent‐thermal method and further reduced with ascorbic acid to obtain TiO2‐PRGO(xh) with a higher degree of reduction (ascorbic acid 80° reduced TiO2‐PRGO x h, x = 1, 2, 3, 4). The composites were characterized using scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transform infrared (FT‐IR), X‐ray diffraction (XRD), X‐ray photoelectron spectroscopy (XPS), and ultraviolet–visible diffuse reflectance spectroscopy (DRS). The transient photocurrent response and electrochemical impedance results show that TiO2‐PRGO has the most outstanding photoelectrochemical properties. Compared with pure TiO2 and other samples, the TiO2‐PRGO nanocomposites exhibited excellent photocatalytic properties, and their photocatalytic efficiencies for the degradation of methylene blue (MB) were up to seven times higher than those of the pure TiO2 nanomaterials, and twice that of TiO2‐PRGO(4h). The photodegradation of methylene blue by the composites decreased as the degree of PRGO reduction increased. The efficient photocatalytic performance of TiO2‐PRGO can be attributed to the high TiO2 loading and good electrical conductivity. Notably, TiO2‐PRGO photocatalysis for 90 min resulted in 100% degradation of MB. Meanwhile, TiO2‐PRGO has good reusability, and the degradation rate of TiO2‐PRGO remained at 95% after four times of degradation in MB solution. [ABSTRACT FROM AUTHOR]

MoS2 lithium-based grease is suitable for lubrication protection between bearings at high temperatures and loads due to its excellent tribological properties. However, there is little research on the influence of different addition methods of MoS2 additive on its tribology and corrosion properties. In this work, eco-friendly vegetable oil was selected as the base oil, with MoS2 powder as the additive to synthesize lithium-based grease. The effects of different adding modes of MoS2 on the tribology and corrosion properties of the grease were studied. The experimental results showed that adding 0.01 wt% MoS2 before thickening (Method D) was more conducive to improving the tribological properties of lithium grease. The average friction coefficient was reduced by 26.1%, and the average wear scar diameter was reduced by 0.16 mm. After grinding and adding (Method B) 0.01 wt% MoS2, the corrosion inhibition efficiency of the steel sheet was as high as 96.97%. The reason was that the tribochemical reaction of MoS2 evenly distributed throughout the grease during friction, forming a thin friction film, reducing friction and wear. The protective film formed by MoS2 and GCr15-bearing steel improved the corrosion inhibition performance of the grease. [ABSTRACT FROM AUTHOR]

Carbon dots (CDs) are spherical zero-dimensional carbon nanomaterials, generally below 10 nm in size, which have received increasing attention in the field of corrosion because of various advantages such as good water solubility, abundant raw materials, and environmental protection. In this work, water-soluble carbon dots (CDs) with particle sizes of 5–10 nm are obtained by electrochemical oxidation with anhydrous ethanol. FTIR, Raman, UV–Vis, XPS, and TEM are used to characterize the obtained CDs, and electrochemical tests are used to investigate the anti-corrosion performance of the CDs. The results reveal that the corrosion inhibition performance increased with the addition of CDs, and the highest corrosion inhibition efficiency reaches 98% when the addition amount is 200 mg/L. Moreover, the inhibition mechanism for CDs needs to be further investigated, and the stable adsorption of CDs on carbon steel to form adsorption film may be the key factor for its good corrosion inhibition performance. [ABSTRACT FROM AUTHOR]

With the prevalence of social media that promote interactivity among people, more organisations rely on Key Opinion Leader (KOL) to interact with potential customers in various social media for brand building. This study explores how KOL's characteristics affect the KOL effectiveness and the outcome of brand image building of skincare products. We also examine the contingent conditions when KOL is more effective in brand image building based on the skincare consciousness of the consumer and whether the consumer is affected by his/her social groups. The knowledge transferred through this study reshape the management models in Enterprise Information Systems. [ABSTRACT FROM AUTHOR]

Iron acquisition is critical for pathogens to proliferate during invasive infection, and the human fungal pathogen Candida albicans is no exception. The iron regulatory network, established in reference strain SC5314 and derivatives, includes the central player Sef1, a transcription factor that activates iron acquisition genes in response to iron limitation. Here, we explored potential variation in this network among five diverse C. albicans strains through mutant analysis, Nanostring gene expression profiling, and, for two strains, RNA-Seq. Our findings highlight four features that may inform future studies of natural variation and iron acquisition in this species. (i) Conformity: In all strains, major iron acquisition genes are upregulated during iron limitation, and a sef1 Δ/Δ mutation impairs that response and growth during iron limitation. (ii) Response variation: Some aspects of the iron limitation response vary among strains, notably the activation of hypha-associated genes. As this gene set is tied to tissue damage and virulence, variation may impact the progression of infection. (iii) Genotype-phenotype variation: The impact of a sef1 Δ/Δ mutation on cell wall integrity varies, and for the two strains examined the phenotype correlated with sef1 Δ/Δ impact on several cell wall integrity genes. (iv) Phenotype discovery: DNA repair genes were induced modestly by iron limitation in sef1 Δ/Δ mutants, with fold changes we would usually ignore. However, the response occurred in both strains tested and was reminiscent of a much stronger response described in Cryptococcus neoformans , a suggestion that it may have biological meaning. In fact, we observed that the iron limitation of a sef1 Δ/Δ mutant caused recessive phenotypes to emerge at two heterozygous loci. Overall, our results show that a network that is critical for pathogen proliferation presents variation outside of its core functions.IMPORTANCEA key virulence factor of Candida albicans is the ability to maintain iron homeostasis in the host where iron is scarce. We focused on a central iron regulator, SEF1 . We found that iron regulator Sef1 is required for growth, cell wall integrity, and genome integrity during iron limitation. The novel aspect of this work is the characterization of strain variation in a circuit that is required for survival in the host and the connection of iron acquisition to genome integrity in C. albicans .

Objective: To determine the changes of Porphyromonas gingivalis (P. gingivalis) growth and metabolism and identify whether the vascular epithelium change could be induced in diabetic periodontitis., Background: Maintaining favourable vascular function is a precondition for periodontal regeneration. In diabetic periodontitis, high glucose levels could enhance the metabolism of pathogens, and a complex condition involving inflammation and high glucose levels would disrupt homeostasis of the epithelium and promote fibrosis by endothelial-to-mesenchymal transition (EndMT)., Methods: Porphyromonas gingivalis was cultured with glucose to judge its metabolic activity. Human umbilical vein endothelial cells (HUVECs) were treated with P. gingivalis-lipopolysaccharide (LPS) (10 μg/ml) and/or high glucose concentrations (25 mM), and transforming growth factor (TGF)-β inhibitor was used to block EndMT. Inflammation level was assessed by flow cytometry. Multiple biological functions including EndMT, angiopoiesis, and cell migration were analysed. Additionally, gene expressions and protein levels were determined with qPCR and western blot, respectively. Finally, blood vessels were cultured ex vivo, and EndMT and fibrosis markers were detected by immunohistochemistry., Results: Glucose could promote P. gingivalis growth and biofilm formation as well as the expression of virulence factor genes including FimA, RgpA, RgpB, and Kgp. P. gingivalis-LPS and glucose could increase intracellular reactive oxygen species (ROS) and promote fibrosis via EndMT in HUVECs, along with attenuating angiopoiesis and cell migration, which could be resumed by blocking EndMT with TGF-β inhibitor. Vascular fibrosis was observed after the addition of glucose via EndMT regulation., Conclusion: Glucose augmented the growth and metabolism of P. gingivalis and promoted fibrosis by the activation of EndMT, as well as the inhibition of angiopoiesis and cell migration., (© 2022 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)