Evaluation of slant crack propagation under RCF in railway rail

Xiangyuan Xu,조두호,장윤석,최재붕,김영진,전현규,서정원,Dae-Sang Kim 대한기계학회 2011 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.25 No.5

Crack propagation due to rolling contact fatigue (RCF) could be a significant potential challenge to the integrity of railway rails because it may lead to a serious disaster. Fatigue cracks subjected to cyclic rolling contact force experience a complex non-proportional mixed loading and complicated boundary condition. In the present research, complex crack opening/closure/sliding/locked behaviors as the cyclic contact loading movement is analyzed considering liquid lubrication action on rail surfaces as well as crack faces. Based on a series of FE analyses, the calculations of the effective SIF ranges for RCF cracks under certain contact loading and boundary conditions are proposed in the form of polynomial functions which will be appropriately used to predict RCF crack growth rate.

State‑of‑health estimation for lithium‑ion batteries using differential thermal voltammetry and Gaussian process regression

Ping Wang,Xiangyuan Peng,Cheng Ze 전력전자학회 2022 JOURNAL OF POWER ELECTRONICS Vol.22 No.7

The state of health (SOH) of lithium-ion batteries is a key factor to ensure the safe and reliable operation of electric vehicles (EVs). Differential thermal voltammetry (DTV) has been shown to be an effective in situ diagnosis method. In this paper, a SOH estimation method for lithium-ion batteries by a fusion of DTV and Gaussian process regression (GPR) is proposed. First, a wavelet transform (WT) is used to smooth DTV curves. Then the health features (HFs) are extracted, and their correlation with capacity loss is quantitatively evaluated through a Pearson correlation coefficient. To compress the data, canonical correlation analysis (CCA) is applied to obtain the canonical health feature (CHF). Subsequently, the GPR algorithm is used to establish the nonlinear mapping relationship between CHF and SOH. Experiments are performed on two datasets at different temperatures. Results show that the proposed method has high estimation accuracy and robustness.

Sphingobacterium bambusae sp. nov., Isolated from Soil of Bamboo Plantation

Shengwen Duan,Zhengchu Liu,Xiangyuan Feng,Ke Zheng,Lifeng Cheng 한국미생물학회 2009 The journal of microbiology Vol.47 No.6

A Gram-negative, non-motile, non-spore-forming bacterial strain designated IBFC2009T was isolated from soil of a bamboo plantation. The strain could grow at 11°C~39°C, pH 6.0~9.0, and in the presence of 0~5% NaCl. Based on 16S rRNA gene sequence analysis, Strain IBFC2009T belonged to the genus Sphingobacterium and showed the highest sequence similarity of 94.6% (S. composti T5-12T) with the type strains within the genus. The major fatty acids were summed feature 3 (iso-C15:0 2-OH and/or C16:1 ω7c, 34.4%), iso-C15:0 (22.4%), C16:0 3-OH (15.2%), and iso-C17:0 3-OH (12.8%). The G+C content of the genomic DNA was 41.0 mol%. According to the phenotypic and genotypic characteristics, Strain IBFC2009T should represent a novel species of the genus Sphingobacterium, for which the name Sphingobacterium bambusae sp. nov. is proposed. The type strain is IBFC2009T (=CCTCC AB 209162T =KCTC 22814T).

Evidence of the genetic diversity and clonal population structure of Oenococcus oeni strains isolated from different wine-making regions of China

Dongliang Yu,Kan Shi,Xiangyuan Wen,Fangshu Xie,Tao Wang,Shuwen Liu,Ling He 한국미생물학회 2018 The journal of microbiology Vol.56 No.8

Studies of the genetic diversity and population structure of Oenococcus oeni (O. oeni) strains from China are lacking compared to other countries and regions. In this study, amplified fragment length polymorphism (AFLP) and multilocus sequence typing (MLST) methods were used to investigate the genetic diversity and regional evolutionary patterns of 38 O. oeni strains isolated from different wine-making regions in China. The results indicated that AFLP was markedly more efficient than MLST for typing O. oeni strains. AFLP distinguished 37 DNA patterns compared to 7 sequence types identified using MLST, corresponding to discriminatory indices of 0.999 and 0.602, respectively. The AFLP results revealed a high level of genetic diversity among the O. oeni strains from different regions of China, since two subpopulations and an intraspecific homology higher than 60% were observed. Phylogenetic analysis of the O. oeni strains using the MLST method also identified two major phylogroups, which were differentiated into two distinct clonal complexes by minimum spanning tree analysis. Neither intragenic nor intergenic recombination verified the existence of the clonal population structure of the O. oeni strains.

SET8 suppression mediates high glucose-induced vascular endothelial inflammation via the upregulation of PTEN

Shen Xuefang,Chen Xiangyuan,Wang Jing,Liu Jing,Wang Zhiyao,Hua Qing,Wu Qichao,Su Yanguang,He Huanzhong,Hu Yuqin,Meng Zhipeng,Xiong Wanxia,Zhu Minmin 생화학분자생물학회 2020 Experimental and molecular medicine Vol.52 No.-

Hyperglycemia-mediated endothelial inflammation participates in the pathogenesis of cardiovascular complications in subjects with diabetes. Previous studies reported that phosphatase and tensin homolog deleted on chromosome ten (PTEN) and SET8 participate in high glucose-mediated endothelial inflammation. In this study, we hypothesize that SET8 regulates PTEN expression, thus contributing to high glucose-mediated vascular endothelial inflammation. Our data indicated that plasma soluble intercellular adhesion molecule-1 (sICAM-1) and endothelial selectin (e-selectin) were increased in patients with diabetes and diabetic rats. PTEN expression was augmented in the peripheral blood mononuclear cells of patients with diabetes and in the aortic tissues of diabetic rats. Our in vitro study indicated that high glucose increased monocyte/endothelial adhesion, endothelial adhesion molecule expression and p65 phosphorylation in human umbilical vein endothelial cells (HUVECs). Moreover, high glucose led to endothelial inflammation via upregulation of PTEN. Furthermore, high glucose inhibited SET8 expression and histone H4 lysine 20 methylation (H4K20me1), a downstream target of SET8. SET8 overexpression reversed the effects of high-glucose treatment. shSET8-mediated endothelial inflammation was counteracted by siPTEN. Furthermore, SET8 was found to interact with FOXO1. siFOXO1 attenuated high glucose-mediated endothelial inflammation. FOXO1 overexpression-mediated endothelial inflammation was counteracted by siPTEN. H4K20me1 and FOXO1 were enriched in the PTEN promoter region. shSET8 increased PTEN promoter activity and augmented the positive effect of FOXO1 overexpression on PTEN promoter activity. Our in vivo study indicated that SET8 was downregulated and FOXO1 was upregulated in the peripheral blood mononuclear cells of patients with diabetes and the aortic tissues of diabetic rats. In conclusion, SET8 interacted with FOXO1 to modulate PTEN expression in vascular endothelial cells, thus contributing to hyperglycemia-mediated endothelial inflammation.

Engineering of a Bacillus subtilis Strain Deficient in Cellulase: Application in Degumming of Ramie

Qi Yang,Shengwen Duan,Lifeng Cheng,Xiangyuan Feng,Ke Zheng,Chunliang Xie,Zhiyuan Liu,Yuande Peng 한국섬유공학회 2019 Fibers and polymers Vol.20 No.1

Degumming is the most important step before ramie fibers are used in textile industry. Conventional chemical degumming technology with alkaline treatment at high temperature causes critical problems in environment. In addition to multiple degumming enzymes (e.g. pectinases and xylanases), Bacillus subtilis strain 168 can also produce cellulase which brings irreversible damage to ramie fibers. In this study, a strain deficient in cellulase was constructed by insertional inactivation of gene eglS to make it suitable for microbial degumming. Results showed that the cellulase activity was not detected in strain ΔeglS, after 25 h of incubation with strain ΔeglS, the weight loss of the ramie fibers was 20.20 %. Though the residual gum content of ramie fibers obtained in microbial degumming process was 19.67 %, microbial intervention followed by diluted alkaline solution treatment showed lower residual gum content (2.73 %) than chemical degumming (2.96 %). The single fiber breaking strength value of ramie fibers from bio-chemical degumming process reached 27.19 cN, which was the highest of three samples. Moreover, bio-chemical degumming process resulted in a 75 % decrease of alkali dosage as compared with chemical degumming process. This study provides a suggestion to genetically modify wild-type strain in order to protect ramie fibers from cellulase damage, and indicates a sustainable alternative for the traditional chemical degumming in the textile industry.

A New Kind of Hybrid UHVDC System Dedicated for Long-Distance Power Delivery and Regional Power Grids Back-to-Back Hierarchical Interconnection

Yongxin Chen,Xianggen Yin,Xingzhu Wang,Xiangyuan Yin,Wenbin Cao,Yuanlin Pan 전력전자학회 2019 ICPE(ISPE)논문집 Vol.2019 No.5

This paper proposes a hybrid UHVDC system dedicated for long-distance power transmission and back-toback interconnection of the receiving region power grids. The receiving terminal of the UHVDC system is formed by the LCC and MMC in cascaded connection. The system combines the merits of hierarchical connection and asynchronous interconnection, which optimizes the network structure of the receiving system and makes the power distribution of the receiving region grids more flexible. The topology of the system is introduced in detail. The control strategy and the DC fault clearing strategy are proposed. Finally, the UHVDC system is built in PSCAD / EMTDC. The simulation verifies the effectiveness of the control strategy, the DC fault clearing strategy and the re-starting strategy. The results indicate that this kind of UHVDC system has a good application prospect in large-capacity long-distance power transmission to the asynchronous regional power grids.

Effects of Different Storage Temperatures on the Physicochemical Properties and Bacterial Community Structure of Fresh Lamb Meat

Ce Liang,Dequan Zhang,Xiaochun Zheng,Xiangyuan Wen,Tongjing Yan,Zhisheng Zhang,Chengli Hou 한국축산식품학회 2021 한국축산식품학회지 Vol.41 No.3

This study was aimed to compare the physicochemical properties and bacterial community structure of tray‐packaged fresh lamb meat under different storage temperatures, such as 4℃ (chilling), –1.5℃ (supercooling), –4℃ (superchilling) and –9℃ (sub-freezing). The total viable counts (TVC), total volatile base nitrogen (TVB-N), bacterial diversity and metabolic pathways were investigated. The results indicated that the shelf life of superchilling and sub-freezing storage was over 70 d, which was significantly longer than that of chilling and supercooling storage. TVC and TVB-N values showed an increasing trend and were correlated well (R2>0.92). And the TVB-N values of lamb meat were exceeded the tolerable limit (15 mg/100 g) only found under chilling and supercooling storage during storage period. At the genus level, Pseudomonas was the core spoilage bacteria then followed Brochothrix for chilling and supercooling storage. Pseudomonas, Ralstonia, Psychrobacter and Acinetobacter were the dominant spoilage bacteria for superchilling and sub-freezing storage. Furthermore, the bacterial community diversity of lamb meat stored at chilling and supercooling storage decreased with the storage time prolonged, which was opposite to the outcome of meat stored under superchilling and sub-freezing storage. For chilling and supercooling storage, the abundance of main metabolisms (carbohydrate metabolism and amino acid metabolism, etc.) of bacteria increased with the storage time prolonged, which was opposite to superchilling storage. This may be related to the bacteria community diversity and the formation of dominant spoilage bacteria. In conclusion, this work provides data for the preservation of fresh lamb meat which will benefit the meat industry.

Physiological and omics analysis of maize inbred lines during late grain development

Jin Xining,Zhai Huijie,Wang Pingxi,Zhang Xiaoxiang,Wu Xiangyuan,Zhang Huaisheng,Chen Shilin,Huang Zhongwen 한국유전학회 2022 Genes & Genomics Vol.44 No.8

Background: There were significant differences in the change of moisture content and grain composition at the late stage of grain development among different maize varieties, but the regulation mechanism is not clear. Objective: To explore the key genes causing the variation in physiological traits of two typical maize inbred lines in late grain development. Methods: The grains at different development stages were selected as materials to determine the content of water, sucrose, starch and ABA. Transcriptomic and proteomic analysis of the materials were performed to screen relevant genes. Results: The grain dehydration rate and the content of sucrose, starch and ABA were showed significant differences between two varieties in the late stage of grain development. The enrichment analysis of common differentially expressed genes (proteins) showed that most of the genes (proteins) were enriched in the extracellular region. The downregulated genes were mainly concentrated in carbohydrate metabolism and lipid metabolism, while the upregulated genes were mainly in response to stress. Furthermore, this study also identified many key candidate genes (dehydrin genes, pathogenesis-related genes, sucrose synthase and secondary metabolites related genes) related to late grain development of maize. Conclusions: The suggested genes related to late grain development of maize can be candidates for further functional study.

Enrichment of Wee1/CDC2 and NF-κB Signaling Pathway Constituents Mutually Contributes to CDDP Resistance in Human Osteosarcoma

Zhengbo Hu,Lugen Li,Wenxing Lan,Xiao Wei,Xiangyuan Wen,Penghuan Wu,Xianliao Zhang,Xinhua Xi,Yufa Li,Liqi Wu,Wenhu Li,Xiaohong Liao 대한암학회 2022 Cancer Research and Treatment Vol.54 No.1

Purpose Osteosarcoma (OS) universally exhibits heterogeneity and cisplatin (CDDP) resistance. Although the Wee1/CDC2 and nuclear factor кB (NF-κB) pathways were reported to show abnormal activation in some tumor cells with CDDP resistance, whether there is any concrete connection is currently unclear. We explored it in human OS cells. Materials and Methods Multiple OS cell lines were exposed to a Wee1 inhibitor (AZD1775) and CDDP to assess the half-maximal inhibitory concentration values. Western blot, coimmunoprecipitation, confocal immunofluorescence, cell cycle, and Cell Counting Kit-8assays were performed to explore the connection between the Wee1/CDC2 and NF-κB pathways and their subsequent physiological contribution to CDDP resistance. Finally, CDDP-resistant PDX-OS xenograft models were established to confirm that AZD1775 restores the antitumor effects of CDDP. Results A sensitivity hierarchy of OS cells to CDDP and AZD1775 exists. In the highly CDDP-tolerant cell lines, Wee1 and RelA were physically crosslinked, which resulted in increased abundance of phosphorylated CDC2 (Y15) and RelA (S536) and consequent modulation of cell cycle progression, survival, and proliferation. Wee1 inhibition restored the effects of CDDP on these processes in CDDP-resistant OS cells. In addition, animal experiments with CDDP-resistant PDX-OS cells showed that AZD1775 combined with CDDP not only restored CDDP efficacy but also amplified AZD1775 in inhibiting tumor growth and prolonged the median survival of the mice. Conclusion Simultaneous enrichment of molecules in the Wee1/CDC2 and NF-κB pathways and their consequent coactivation is a new molecular mechanism of CDDP resistance in OS cells. OS with this molecular signature may respond well to Wee1 inhibition as an alternative treatment strategy. Purpose Osteosarcoma (OS) universally exhibits heterogeneity and cisplatin (CDDP) resistance. Although the Wee1/CDC2 and nuclear factor кB (NF-κB) pathways were reported to show abnormal activation in some tumor cells with CDDP resistance, whether there is any concrete connection is currently unclear. We explored it in human OS cells.Materials and Methods Multiple OS cell lines were exposed to a Wee1 inhibitor (AZD1775) and CDDP to assess the half-maximal inhibitory concentration values. Western blot, coimmunoprecipitation, confocal immunofluorescence, cell cycle, and Cell Counting Kit-8assays were performed to explore the connection between the Wee1/CDC2 and NF-κB pathways and their subsequent physiological contribution to CDDP resistance. Finally, CDDP-resistant PDX-OS xenograft models were established to confirm that AZD1775 restores the antitumor effects of CDDP.Results A sensitivity hierarchy of OS cells to CDDP and AZD1775 exists. In the highly CDDP-tolerant cell lines, Wee1 and RelA were physically crosslinked, which resulted in increased abundance of phosphorylated CDC2 (Y15) and RelA (S536) and consequent modulation of cell cycle progression, survival, and proliferation. Wee1 inhibition restored the effects of CDDP on these processes in CDDP-resistant OS cells. In addition, animal experiments with CDDP-resistant PDX-OS cells showed that AZD1775 combined with CDDP not only restored CDDP efficacy but also amplified AZD1775 in inhibiting tumor growth and prolonged the median survival of the mice.Conclusion Simultaneous enrichment of molecules in the Wee1/CDC2 and NF-κB pathways and their consequent coactivation is a new molecular mechanism of CDDP resistance in OS cells. OS with this molecular signature may respond well to Wee1 inhibition as an alternative treatment strategy.