Search

As an efficient and environmental‐friendly strategy, electrocatalytic oxidation can realize biomass lignin valorization by cleaving its aryl ether bonds to produce value‐added chemicals. However, the complex and polymerized structure of lignin presents challenges in terms of reactant adsorption on the catalyst surface, which hinders further refinement. Herein, NiCo‐based metal‐organic frameworks (MOFs) are employed as the electrocatalyst to enhance the adsorption of reactant molecules through π‐π interaction. More importantly, lattice strain is introduced into the MOFs via curved ligand doping, which enables tuning of the d‐band center of metal active sites to align with the reaction intermediates, leading to stronger adsorption and higher electrocatalytic activity toward bond cleavage within lignin model compounds and native lignin. When 2′‐phenoxyacetophenone is utilized as the model compound, high yields of phenol (76.3%) and acetophenone (21.7%) are achieved, and the conversion rate of the reactants reaches 97%. Following pre‐oxidation of extracted poplar lignin, >10 kinds of phenolic compounds are received using the as‐designed MOFs electrocatalyst, providing ≈12.48% of the monomer, including guaiacol, vanillin, eugenol, etc., and p‐hydroxybenzoic acid dominates all the products. This work presents a promising and deliberately designed electrocatalyst for realizing lignin valorization, making significant strides for the sustainability of this biomass resource. [ABSTRACT FROM AUTHOR]

The process of transformation and superposition from the Paleo-Asian Ocean to the Paleo-Pacific Ocean tectonic systems have been a critical scientific issue. However, the final closure of the Paleo-Asian Ocean and the initial subduction time of the Paleo-Pacific Ocean, together with the conversion between them in Northeast China, still remain controversial. The Triassic granites in the Jiamusi Block are located in the key position of Northeast China, recording the conversion process of two tectonic domains. Through systematic geochronology and geochemical studies, it can provide important constraints for revealing the superposition and conversion mechanism of the Paleo-Asian Ocean and the Paleo-Pacific Ocean and the early subduction history of the Paleo-Pacific Ocean plate. In this study, the granites in Jiamusi Block were formed in the Early–Middle Triassic (250–245 Ma), characterized by high Si, rich alkali, poor Mg, and are obviously enriched in light rare earth elements and large ion lithophile elements, depleting in high field strength elements such as Nb, Ta, and Ti. They have typical characteristics of continental magmatic arc, deriving from partial melting of amphibolite facies and garnet amphibolite facies mafic lower crust. Combined with zircon Hf isotope results, zircon εHf(t) values are −6.52 to + 9.79, and the two-stage Hf model ages are 0.6–1.7 Ga, indicating that the magma should be derived from a relative younger crustal source, and some ancient materials may be added. Moreover, based on the spatial-temporal framework and Hf isotope characteristics of magmatism in Northeast China, we believe that the Jiamusi Block belonged to an exotic block. Meanwhile, combined with geochronological and geochemical data of igneous rocks on the Jiamusi Block, we suggest that the evolution of Jiamusi Block was dominated by the Paleo-Pacific Ocean rather than Paleo-Asian Ocean during the Triassic, which means the subduction of Paleo-Pacific Ocean plate initiated at least in Early Triassic. [ABSTRACT FROM AUTHOR]

During malignant tumour development, the extracellular matrix (ECM) is usually abnormally regulated. Dysregulated expression of lysyl oxidase‐like 2 (LOXL2), matrix metalloproteinase 9 (MMP9) and lipocalin 2 (LCN2) are associated with ECM remodelling. In this study, protein–protein interaction assays indicated that LCN2 and LOXL2 interactions and LCN2 and MMP9 interactions occurred both intracellularly and extracellularly, but interactions between LOXL2 and MMP9 only occurred intracellularly. The LCN2/LOXL2/MMP9 ternary complex promoted migration and invasion of oesophageal squamous cell carcinoma (ESCC) cells, as well as tumour growth and malignant progression in vivo, while the iron chelator deferoxamine mesylate (DFOM) inhibited ESCC tumour growth. Co‐overexpression of LCN2, LOXL2 and MMP9 enhanced the ability of tumour cells to degrade fibronectin and Matrigel, increased the formation and extension of filopodia, and promoted the rearrangement of microfilaments through upregulation of profilin 1. In addition, the LCN2/LOXL2/MMP9 ternary complex promoted the expression of testican‐1 (SPOCK1), and abnormally activated the FAK/AKT/GSK3β signalling pathway. In summary, the LCN2/LOXL2/MMP9 ternary complex promoted the migration and invasion of cancer cells and malignant tumour progression through multiple mechanisms and could be a potential therapeutic target. [ABSTRACT FROM AUTHOR]

A large number of jackup offshore platforms with towers are widely applied in ocean engineering. The dynamic response of the platforms to waves of large wave height is critical, as such waves may cause platform accidents, property damage, and casualties. Therefore, it is important to investigate the coupling effect of jackup offshore platform, towers and seabed foundations under waves of large wave height. In this study, the coupling effect of offshore platforms, tower structures, and seabed foundations under the impact of waves of large wave height was studied via a physical flume model test. The experimental results show that the impact of waves of large wave height on the platforms is significant when the wave is blocked by the platform surface as the water body gathers under the platform surface, causing a pile group effect that results in the onshore piles being subjected to larger pressures than the front ones. The combined action of wave impact and pile leg squeezing force leads to an increase in the pore pressure of the foundation bed near the pile leg, and the soil near the pile leg becomes soft, revealing the mechanism of instability of the offshore platform's pile foundation under waves of large wave height. The acceleration of the longitudinal movement of the platform increases under waves of large wave height, and the vortex-induced vibration of the platform includes the vibration along the direction of the wave and perpendicular to it. A coupled vibration effect between the tower structure and the platform occurs under waves of large wave height, reducing the vibration of the platform itself. Furthermore, damping members are installed on the tower structure, greatly reducing the natural vibration period and the motion response of the tower structure. This study provides significant enlightenment for the design of offshore platforms with towers to protect against waves of large wave height. [ABSTRACT FROM AUTHOR]

Stock transaction data transmission has extremely strong requirements for real‐time transmission. However, the volume of stock trading data continues to increase. The traditional end‐to‐end transmission mechanism has become difficult to meet the real‐time requirements of stock trading. In this paper, we propose an efficient stock transaction data transmission mechanism based on distributed network caching. By introducing elastic storage space at the edge, enabling intelligent transaction data push in the cloud, and introducing passive caching at the client, it effectively solves the real‐time requirement of stock transaction data transmission. [ABSTRACT FROM AUTHOR]

Objectives The application of Light's criteria misidentifies approximately 30% of transudates as exudates, particularly in patients on diuretics with cardiac effusions. The purpose of this study was to establish a predictive model to effectively identify cardiac effusions misclassified by Light's criteria. Methods We retrospectively studied 675 consecutive patients with pleural effusion diagnosed by Light's criteria as exudates, of which 43 were heart failure patients. A multivariate logistic model was developed to predict cardiac effusions. The performance of the predictive model was assessed by receiver operating characteristic (ROC) curves, as well as by examining the calibration. Results It was found that protein gradient of >23 g/L, pleural fluid lactate dehydrogenase (PF-LDH) levels, ratio of pleural fluid LDH to serum LDH level (P/S LDH), pleural fluid adenosine deaminase (PF-ADA) levels, and N-terminal pro–brain natriuretic peptide (NT-pro-BNP) levels had a significant impact on the identification of cardiac effusions, and those were simultaneously analyzed by multivariate regression analysis. The area under the curve (AUC) value of the model was 0.953. The model also had higher discriminatory properties than protein gradients (AUC, 0.760) and NT-pro-BNP (AUC, 0.906), all at a P value of <.01. Conclusion In cases of suspected cardiac effusion, or where clinicians cannot identify the cause of an exudative effusion, this model may assist in the correct identification of exudative effusions as cardiac effusions. [ABSTRACT FROM AUTHOR]

Monolithic macroporous composites constructed by poly(glycidyl methacrylate‐2‐hydroxyethyl methacrylate)/SiO2 nanofilm (P(GMA‐HEMA)/SiO2) were prepared and then used as the supports for immobilization of Pseudomonas fluorescens lipase (PFL). The as‐prepared macroporous materials were characterized by scanning electron microscope (SEM), N2 adsorption‐desorption experiments, Fourier transform infrared (FT‐IR) spectroscopy and thermogravimetric (TG) analysis. The immobilization conditions and the properties of the immobilized PFL were investigated. The characterization results revealed that the macroporous SiO2 has a 3D continuous pass‐through macropore structure, large pore volume and high specific surface area. After modification with P(GMA‐HEMA) and the subsequent immobilization of PFL, the structural characteristics were preserved. Under the optimum conditions, the activity of the immobilized PFL reached to 3773 U g−1 and enzyme activity recovery achieved to 232 %. Compared with free lipase, the thermal and pH stabilities of the immobilized lipase were significantly enhanced, and it also exhibited an outstanding reusability. [ABSTRACT FROM AUTHOR]