A Novel Bone Gelatin Prepared by Enzymatic Catalysis with High Crosslinking Activity of MTGase for Gelatinization Properties of Minced Pork

A novel gelatin prepared by enzymatic catalysis (type-E bone gelatin) was developed in our group. In this study, the high crosslinking activity of type-E bone gelatin with microbial transglutaminase (MTGase) was found and further used for the gelatinization properties of minced pork. The results showed that the contents of lysine and glutamine in type-E bone gelatin were higher than that of traditional gelatin prepared by acid (type-A gelatin) and alkali (type-B gelatin) methods, which are as action sites for MTGase. The crosslinking degree (79%) of type-E was approximately 4.9 times that of type-A and 5.6 times that of type-B at 1.44 U/g MTGase. Moreover, the type-E gel showed thermal irreversibility when the MTGase concentration was higher than 0.90 U/g due to high crosslinking activity. For minced pork gel, the water-holding capacity and texture properties of minced pork modified with type-E bone gelatin crosslinked by MTGase were improved and cooking loss was significantly reduced

PGN and LTA from Staphylococcus aureus Induced Inflammation and Decreased Lactation through Regulating DNA Methylation and Histone H3 Acetylation in Bovine Mammary Epithelial Cells

Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli) are the most common pathogens of mastitis, and S. aureus generally causes subclinical mastitis which is more persistent and resistant to treatment. Peptidoglycan (PGN) and lipoteichoic acid (LTA) are cell wall components of S. aureus. Although the roles of PGN and LTA in causing inflammation are well studied, the epigenetic mechanisms of the effects of PGN and LTA on the inflammation and lactation remain poorly understood. This study characterized the gene expression profiling by RNA sequencing and investigated DNA methylation and histone acetylation in relation to inflammation and lactation in the immortalized bovine mammary epithelial cell line (MAC-T). The cells were cultured for 24 h with neither PGN nor LTA (CON), PGN (30 μg/mL), LTA (30 μg/mL), and PGN (30 μg/mL) + LTA (30 μg/mL), respectively. The number of differentially expressed genes (DEGs) and the expression of proinflammatory factors including interleukin (IL)-1β, IL-6, IL-8, chemokine (C-X-C motif) ligand (CXCL)1, and CXCL6 of the treatments increased in the following order: CON < PGN < LTA < PGN + LTA, and the DEGs mainly enriched on the cytokine-cytokine receptor interaction and chemokine signaling pathway. LTA and PGN + LTA induced hypomethylation of global DNA by suppressing DNA methyltransferase (DNMT) activity. PGN and LTA, alone or combined, decreased the mRNA expression of casein genes (CSN1S1, CSN2, and CSN3) and the expression of two caseins (CSN2 and CSN3), and reduced histone H3 acetylation by suppressing histone acetyltransferase (HAT) activity and promoting histone deacetylase (HDAC) activity. Collectively, this study revealed that PGN and LTA induced inflammation probably due to decreasing DNA methylation through regulating DNMT activity, and decreased lactation possibly through reducing histone H3 acetylation by regulating HAT and HDAC activity in bovine mammary epithelial cells

A New Design Optimization Method for Permanent Magnet Synchronous Linear Motors

This study focused on the design optimization of permanent magnet synchronous linear motors (PMSLM) that are applied in microsecond laser cutting machines. A new design optimization method was introduced to enhance PMSLM performances in terms of motor thrust, thrust ripple, and inductive electromotive force (EMF). Based on accurate 3D finite element analysis (3D-FEA), a multiple support vector machine (multi-SVM) was proposed to build a non-parametric quick calculation model by mapping the relation between multivariate structure parameters and multivariate operation performances. The gravity center neighborhood algorithm (GCNA) was also applied to search the global optimal combination of the structure parameters by locating the gravity center of the multi-SVM model. The superiority and validity of this method are verified by experiments

Engineering the Coordination Sphere of Isolated Active Sites to Explore the Intrinsic Activity in Single-Atom Catalysts

Abstract Reducing the dimensions of metallic nanoparticles to isolated, single atom has attracted considerable attention in heterogeneous catalysis, because it significantly improves atomic utilization and often leads to distinct catalytic performance. Through extensive research, it has been recognized that the local coordination environment of single atoms has an important influence on their electronic structures and catalytic behaviors. In this review, we summarize a series of representative systems of single-atom catalysts, discussing their preparation, characterization, and structure–property relationship, with an emphasis on the correlation between the coordination spheres of isolated reactive centers and their intrinsic catalytic activities. We also share our perspectives on the current challenges and future research promises in the development of single-atom catalysis. With this article, we aim to highlight the possibility of finely tuning the catalytic performances by engineering the coordination spheres of single-atom sites and provide new insights into the further development for this emerging research field

Ultrasmall MoOx clusters as a novel cocatalyst for photocatalytic hydrogen evolution

To enhance the performance of semiconductor photocatalysts, cocatalysts are used to accelerate surface reactions. Herein, ultrasmall molybdenum–oxygen (MoOx) clusters are developed as a novel non-noble cocatalyst, which significantly promotes the photocatalytic hydrogen generation rate of CdS nanowires (NWs). As indicated by extended X-ray absorption fine structure analysis, direct bonds are formed between CdS NWs and MoOx clusters, which guarantee the migration of photo-generated charge carriers. Moreover, the MoOx clusters induce deep electron trap states owing to the unique atomic arrangement and configuration with the generation of long-lived electrons to enhance the activity. These findings may guide the design of efficient cocatalytic materials for solar water splitting and open a new avenue toward practical applications of ultrasmall clusters.H.Z. and P.Z. contributed equally to this work. X.W.L. acknowledges the funding support from the Korea Institute of Energy Technology Evaluation and Planning (KETEP) and the Ministry of Trade, Industry, & Energy (MOTIE) of the Republic of Korea through the grant (No. 20168510050080)