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This paper utilizes data mining algorithms to predict the evaluation value of new items by target users in an interactive learning environment. To enhance data quality, redundant data in the dataset is eliminated. To provide better learning recommendations and personalized services, prediction accuracy is assessed by calculating the deviation between predicted and actual ratings. Teachers and students can use the analysis results of feature weights, correct word cut scores, and other indicators obtained from data mining as key learning references. In the data mining analysis of students’ English learning data, the feature weight is 0.921, which helps to assess students’ knowledge mastery and learning effect more accurately.

The extremely low melt flowability of ultra‐high molecular weight polyethylene (UHMWPE) is the primary obstacle to its melt processing. Particularly in melt spinning processes, the extremely high molecular weight of UHMWPE and the density of entangled molecular chains severely limit its production efficiency and monofilament performance. This study investigates the effect of flow modifiers on the melt spinning process of UHMWPE/HDPE blends, focusing on CaSt2, PEG, and CaSt2/silicone powder composite additives, and their impact on the standard tensile samples and monofilament tensile properties of UHMWPE/HDPE. The mechanism of additive influence on the tensile properties of UHMWPE/HDPE blends is analyzed through tensile strength testing, thermal analysis, and microscopic morphology observation. The results show that in standard tensile samples, CaSt2 or CaSt2/silicone powder composite additives can enhance the crystallinity of the blend, thereby improving its tensile strength. Conversely, adding PEG significantly reduces the crystallinity and tensile strength of the blend. The maximum tensile strength of CaSt2‐modified UHMWPE/HDPE monofilament is 1236.61 MPa. This enhancement is attributed to the lubricating effect of CaSt2, which simultaneously assists the molecular chains in the amorphous region, and the reorientation of the stress‐induced molten lamellar structure under tension, greatly promoting the formation of straight‐chain crystals in the monofilament. During hot drawing, PEG inhibits the formation of straight‐chain crystals in the monofilament, resulting in a 3.06% decrease in maximum crystallinity compared with standard tensile samples. When CaSt2 is combined with silicone powder, the additives tend to aggregate during hot drawing, and these larger aggregate particles hinder the orientation of molecular chains along the drawing direction, resulting in a 30.75% decrease in maximum tensile strength of the monofilament compared with the standard tensile samples. Highlights: The tensile property of UHMWPE/HDPE blends modified with additives was discussed.Analytical techniques including DSC, SEM, and tensile strength tests were used.The maximum tensile strength of the monofilament can reach up to 1236.61 MPa.UHMWPE/HDPE/CaSt2 = 60/40/0.5 exhibits the best tensile property. [ABSTRACT FROM AUTHOR]

The challenging melt processing of ultrahigh‐molecular‐weight polyethylene (UHMWPE) melt spinning hinders its efficiency and quality, which can be improved by processing aids that enhance its flowability. Building upon modifications of UHMWPE with high‐density polyethylene (HDPE), this article studies the effects of CaSt2, polyethylene glycol (PEG), silicone powder, and their compound additives on the processing performance of UHMWPE/HDPE blends. The modification effects and mechanisms are studied by analyzing processing torque, melt flow rate, viscoelastic activation energy, and rheological performance. The research results indicate that 1 wt% PEG significantly improves the processing flowability of UHMWPE/HDPE blends, and PEG mainly plays an internal lubrication role on the molecular chains of the blends. The combination of 0.5 wt% CaSt2 and 0.5 wt% silicone powder exhibits a synergistic effect of internal and external lubrication on the UHMWPE/HDPE blends melt processing, further improving the processing performance of UHMWPE/HDPE blends. Compared with unmodified blends, the maximum screw speed for obtaining qualified as‐spun filaments of UHMWPE/HDPE blends modified with CaSt2/silicone powder compound additives increases from 5 to 20 rpm, which means that the critical shear rate of the modified UHMWPE/HDPE blend melt processing is significantly improved. Meanwhile, the processing torque decreases by about 22%. [ABSTRACT FROM AUTHOR]

This article discusses the development of an improved and eco-friendly synthesis method for (R)-5,7-difluorochroman-4-ol, a key intermediate in the production of Tegoprazan, a medication used to treat acid-related diseases. The researchers optimized the reaction conditions and achieved a high yield and purity of the desired product using lipase-catalyzed resolution and Mitsunobu inversion. This method shows promise for practical use in the green synthesis of Tegoprazan due to its efficiency and environmental sustainability. The document provides a detailed account of the synthesis process and acknowledges financial support from the CQMU Program for Youth Innovation in Future Medicine. [Extracted from the article]

The electrochemical production of hydrogen peroxide (H2O2) using metal‐free catalysts has emerged as a viable and sustainable alternative to the conventional anthraquinone process. However, the precise architectural design of these electrocatalysts poses a significant challenge, requiring intricate structural engineering to optimize electron transfer during the oxygen reduction reaction (ORR). Herein, we introduce a novel design of covalent organic frameworks (COFs) that effectively shift the ORR from a four‐electron to a more advantageous two‐electron pathway. Notably, the JUC‐660 COF, with strategically charge‐modified benzyl moieties, achieved a continuous high H2O2 yield of over 1200 mmol g−1 h−1 for an impressive duration of over 85 hours in a flow cell setting, marking it as one of the most efficient metal‐free and non‐pyrolyzed H2O2 electrocatalysts reported to date. Theoretical computations alongside in situ infrared spectroscopy indicate that JUC‐660 markedly diminishes the adsorption of the OOH* intermediate, thereby steering the ORR towards the desired pathway. Furthermore, the versatility of JUC‐660 was demonstrated through its application in the electro‐Fenton reaction, where it efficiently and rapidly removed aqueous contaminants. This work delineates a pioneering approach to altering the ORR pathway, ultimately paving the way for the development of highly effective metal‐free H2O2 electrocatalysts. [ABSTRACT FROM AUTHOR]

Background: Although numerous studies had revealed associations between autoimmune diseases (AIDs) and thyroid cancer (TC), the potential causal associations between the two remain poorly defined., Methods: Using five approaches, two-sample Mendelian randomization (MR) analyses were carried out to determine the causal effects of 12 major AIDs on risk of TC. The sensitivity analyses were conducted to verify the reliability of the analysis. The reverse MR analysis was performed to evaluate the possibility of reverse causation., Results: The results showed a significant causal association of systemic lupus erythematosus (SLE) and primary biliary cirrhosis (PBC) on the risk of TC. Genetically predicted PBC elevated the risk of TC (OR = 1.46, 95% CI = 1.06-2.02, p = 0.021). The risk of TC was also increased by genetically predicted SLE (OR = 6.52, 95% CI = 1.38-30.84, p = 0.018) with heterogeneity. After outlier-corrected analyses, the results still suggested that genetically predicted SLE increased the risk of TC ( p = 0.019). No evidence of a causal relationship between the remaining 10 AIDs and TC was observed. No reverse causal effects of TC on AIDs were found in reverse MR analysis., Conclusion: These findings support a significant causal association of SLE/PBC on the increased risk of TC, indicating that patients with SLE/PBC should be under a close monitoring of TC., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Peng, Xu, Zhou, Du, Ge and Huang.)