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Activation of the epidermal growth factor receptor (EGFR) is crucial for development, tissue homeostasis, and immunity. Dysregulation of EGFR signaling is associated with numerous diseases. EGFR ubiquitination and endosomal trafficking are key events that regulate the termination of EGFR signaling, but their underlying mechanisms remain obscure. Here, we reveal that ZNRF1, an E3 ubiquitin ligase, controls ligand-induced EGFR signaling via mediating receptor ubiquitination. Deletion of ZNRF1 inhibits endosome-to-lysosome sorting of EGFR, resulting in delayed receptor degradation and prolonged downstream signaling. We further demonstrate that ZNRF1 and Casitas B-lineage lymphoma (CBL), another E3 ubiquitin ligase responsible for EGFR ubiquitination, mediate ubiquitination at distinct lysine residues on EGFR. Furthermore, loss of ZNRF1 results in increased susceptibility to herpes simplex virus 1 (HSV-1) infection due to enhanced EGFR-dependent viral entry. Our findings identify ZNRF1 as a novel regulator of EGFR signaling, which together with CBL controls ligand-induced EGFR ubiquitination and lysosomal trafficking.

Excessive generation and accumulation of highly reactive oxidizing molecules causes oxidative stress and oxidative damage to cellular components. Accumulating evidence indicates that autophagy diminishes oxidative damage in cells and maintains redox homeostasis by degrading and recycling intracellular damaged components. Here, we show that TRAF6 E3 ubiquitin ligase and A20 deubiquitinase coordinate to regulate ATG9A ubiquitination and autophagy activation in cells responding to oxidative stress. The ROS-dependent TRAF6-mediated non-proteolytic, K48/63-linked ubiquitination of ATG9A enhances its association with Beclin 1 and the assembly of VPS34-UVRAG complex, thereby stimulating autophagy. Notably, expression of the ATG9A ubiquitination mutants impairs ROS-induced VPS34 activation and autophagy. We further find that lipopolysaccharide (LPS)-induced ROS production also stimulates TRAF6-mediated ATG9A ubiquitination. Ablation of ATG9A causes aberrant TLR4 endosomal trafficking and decreases IRF-3 phosphorylation in LPS-stimulated macrophages. Our findings provide important insights into how K48/K63-linked ubiquitination of ATG9A contributes to the regulation of oxidative stress-induced autophagy.

This paper investigates using an optical measurement method to determine the concentration ratio in a liquid mixture of methanol and ethanol. To better understand the relative mixture solution concentration, the dilution method is used to determine slight variations in the refractive index of the variable mixture concentration. The test concentration range of both methanol and ethanol is between 0–90%. The results of our analysis indicate that the refractive index of a mixture of methanol and ethanol lies in the interval between the refractive index of pure ethanol and methanol. The optical property of the mixture is similar to that of the solution material with the highest quantity. Regression analysis using a quadratic function resulted in an error of 25%. Regression analysis using a cubic function reduced the error to 6.25%. Therefore, the regression analysis function used in this study is the cubic function, as the mixture solution includes the methanol liquid. Combining the optical measurement and dilution methods can yield the solution concentration of the liquid mixture.

This study develops a high precision non destructive measurement technique based on a laser interferometer for determining the mixture of methanol and ethanol from its refractive index. The optical metrology system is employed to measure the refractive indexes of mixture sample with known methanol and ethanol. The ratio set of the mixture sample have seven sets. The refractive index of the ethanol solution with the methanol alcohol is reduced. When the mixture solution includes the methanol and ethanol, the refractive index of the mixture solution is between the refractive index of the ethanol and methanol. When the refractive index of the solution is very close the refractive index of the ethanol alcohol, the effect of the mixture solution in refractive index is very small. From this experimental result, the effect of the refractive index of the mixture solution in the refractive index of the ingredient liquid is very clear.

This study develops a high-precision, nondestructive measurement technique based on a laser interferometer for determining the methanol concentration of a liquid solution from its refractive index. The optical metrology system is employed to measure the refractive indexes of samples with known methanol concentrations ranging from 0 ~ 90%. The error between the experimental refractive index and the literature refractive index is small than 0.00062. The error between the measured value of the refractive index and the analytically derived value is reduced form 0.00064 to 0.00007. The decreased error ratio is about 89%. When the relative function between the refractive index and methyl alcohol concentration is cubic, this can reduce the regressional analysis error. By applying regressional analysis to the experimental results, an analytical expression is derived to describe the cubic relationship between the refractive index and the methanol concentration. An excellent agreement is observed between the experimentally determined values of the methanol concentration and the analytically predicted results.

In this paper, the authors present a video content summarization for recommendation (called VCSR) system to auto-recommend suitable multimedia learning materials for learners. The VCSR system firstly extracts important content as summarization from input raw video data, while the generated summarization will be auto-routed to learners according to their profiles. Video captions are initially recognized using optical character recognition (OCR), then a set of key passages with corresponding frame images are extracted to form a video summary. The recommendation is achieved by calculating the relevance of the video summarization for each learner. Also, this paper indicates how the VCSR system effectively plays the intermediate role in a modern digital library.