Effects of Si on the Microstructure and Work Hardening Behavior of Fe‒17Mn‒1.1C‒xSi High Manganese Steels

Renlong Xiong,Yi Liu,Haitao Si,Huabei Peng,Shanling Wang,Binhan Sun,Hanxin Chen,Hyoung Seop Kim,Yuhua Wen 대한금속·재료학회 2021 METALS AND MATERIALS International Vol.27 No.10

In order to improve the work hardening capacity under low stresses and the yield strength of conventional Hadfield steels, theeffects of Si on the microstructure and work hardening behavior of the Fe‒17Mn‒1.1C‒xSi steels under both quasi-statictensile and low load impact are investigated. It is shown that the increase of the Si contents remarkably improves the yieldstrength by 36 MPa per 1 wt% Si in the investigated steel system without significant sacrifice of ductility. The decreasingeffect of Si on the stacking fault energy is strongly affected by carbon, although the variation of carbon content was small. This led to the unexpected similar stacking fault energy between 1Si and 2Si steel. With the increase of the Si contents forthe steels, the critical strain for the onset of mechanical twinning was lowered, which was controlled by the cooperationbetween the stacking fault energy and solid solution strengthening of Si. This resulted in the earlier initiation of mechanicaltwins and an increase in the twin volume fraction. Therefore, the work hardening capacities under both quasi-static tensileand low load impact tests were enhanced. It was also found that the impact deformation decreased as more mechanical twinsabsorbed the impact energy.

Relation between the local structure and solid solubility of the layered material LiMO2 (M=Co, Ni, Fe) in Li2MnO3

Chen Hou,Xiang Xiao,Yi-Ran Xing,Le-Le Yu,Yong-Heng Si,Han Lu,Yu-Juan Zhao 대한금속·재료학회 2022 ELECTRONIC MATERIALS LETTERS Vol.18 No.1

Although low solid solubility and activity of LiFeO2in xLi2MnO3·(1–x)LiFeO2 limit its practical application, it still has thepotential to become a new-generation cathode material without cobalt or nickel for Li-ion batteries. In order to understand theeffects of the local structures of different LiMO2(M = Co, Ni, Fe) layered materials on their solid solubility in Li2MnO3,partialdensities of states are calculated to determine the Jahn–Teller distortion in the layered cathode material, and the first-principlescalculation method based on density functional theory is used to optimize and compare the local structures of LiCoO2,LiNiO2,LiFeO2,LiMnO2,and Li2MnO3. The degrees of distortion of the transition metal–oxygen (M–O) and lithium–oxygen (Li–O)octahedra in the crystal structure of the material are evaluated. It is clear that the solid solubility of layered materials is relatedto the bond lengths and degrees of distortion of the M–O and Li–O octahedra. Among them, the similar bond length of LiNiO2and Li2MnO3and the high distortion of NiO6enhance the solid solubility of LiNiO2in Li2MnO3. Owing to the absence ofJahn–Teller distortion in LiFeO2and LiCoO2,the FeO6and CoO6octahedra are slightly distorted, thereby decreasing thesolid solubility of LiMO2(M = Fe, Co) in Li2MnO3. Understanding the relation between intra-octahedral distortion and solidsolubility provides simple and efficient evidence for comparing the solid solubilities of different LiMO2layered materials inthe Li2MnO3of Li-rich cathode materials. This study can be used as a reference for component design in Li-rich materials.

A novel computer vision-based vibration measurement and coarse-to-fine damage assessment method for truss bridges

Yi-Qing Ni,Wen-Qiang Liu,En-Ze Rui,Lei Yuan,Si-Yi Chen,You-Liang Zheng 국제구조공학회 2023 Smart Structures and Systems, An International Jou Vol.31 No.4

To assess structural condition in a non-destructive manner, computer vision-based structural health monitoring (SHM) has become a focus. Compared to traditional contact-type sensors, the advantages of computer vision-based measurement systems include lower installation costs and broader measurement areas. In this study, we propose a novel computer vision-based vibration measurement and coarse-to-fine damage assessment method for truss bridges. First, a deep learning model FairMOT is introduced to track the regions of interest (ROIs) that include joints to enhance the automation performance compared with traditional target tracking algorithms. To calculate the displacement of the tracked ROIs accurately, a normalized cross-correlation method is adopted to fine-tune the offset, while the Harris corner matching is utilized to correct the vibration displacement errors caused by the non-parallel between the truss plane and the image plane. Then, based on the advantages of the stochastic damage locating vector (SDLV) and Bayesian inference-based stochastic model updating (BISMU), they are combined to achieve the coarse-to-fine localization of the truss bridge's damaged elements. Finally, the severity quantification of the damaged components is performed by the BI-SMU. The experiment results show that the proposed method can accurately recognize the vibration displacement and evaluate the structural damage.

Complex roles of the stroma in the intrinsic resistance to gemcitabine in pancreatic cancer: where we are and where we are going

Chen Liang,Si Shi,Qingcai Meng,Dingkong Liang,Shunrong Ji,Bo Zhang,Yi Qin,Jin Xu,Quanxing Ni,Xianjun Yu 생화학분자생물학회 2017 Experimental and molecular medicine Vol.49 No.-

Pancreatic ductal adenocarcinoma (PDAC) is among the most devastating human malignancies. The poor clinical outcome in PDAC is partly attributed to a growth-permissive tumor microenvironment. In the PDAC microenvironment, the stroma is characterized by the development of extensive fibrosis, with stromal components outnumbering pancreatic cancer cells. Each of the components within the stroma has a distinct role in conferring chemoresistance to PDAC, and intrinsic chemoresistance has further worsened this pessimistic prognosis. The nucleoside analog gemcitabine (GEM) is usually the recommended first-line chemotherapeutic agent for PDAC patients and is given alone or in combination with other agents. The mechanisms of intrinsic resistance to GEM are an active area of ongoing research. This review highlights the important role the complex structure of stroma in PDAC plays in the intrinsic resistance to GEM and discusses whether antistroma therapy improves the efficacy of GEM. The addition of antistroma therapy combined with GEM is expected to be a novel therapeutic strategy with significant survival benefits for PDAC patients.

Zebrafish Dnd protein binds to 3`UTR of geminin mRNA and regulates its expression

( Shu Chen ),( Mei Zeng ),( Hua Qin Sun ),( Wen Qian Deng ),( Yi Lu Lu ),( Da Chang Tao ),( Yun Qiang Liu ),( Si Zhong Zhang ),( Yong Xin Ma ) 생화학분자생물학회 (구 한국생화학분자생물학회) 2010 BMB Reports Vol.43 No.6

Dnd (dead end) gene encodes an RNA binding protein and is specifically expressed in primordial germ cells (PGCs) as a vertebrate-specific component of the germ plasma throughout embryogenesis. By utilizing a technique of specific nucleic acids associated with proteins (SNAAP), 13 potential target mRNAs of zebrafish Dnd (ZDnd) protein were identified from 8-cell embryo, and 8 target mRNAs have been confirmed using an RT-PCR analysis. Of the target mRNAs, the present study is focused on the regulation of geminin, which is an inhibitor of DNA replication. Using electrophoretic mobility shift assay (EMSA), we demonstrated that ZDND protein bound the 67-nucleotide region from 864 to 931 in the 3`UTR of geminin mRNA, a sequence containing 60.29% of uridine. Results from a dual-luciferase assay in HEK293 cells showed that ZDND increases the translation of geminin. Taken together, the identification of target mRNA for ZDnd will be helpful to further explore the biological function of Dnd in zebrafish germ-line development as well as in cancer cells. [BMB reports 2010; 43(6): 438-444]

Autophagy Involvement in Olanzapine-Mediated Cytotoxic Effects in Human Glioma Cells

Wang, Yi-Xuan,Xu, Shu-Qing,Chen, Xiang-Hui,Liu, Rui-Si,Liang, Zhong-Qin Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.19

The aim of this study was to investigate the effects of olanzapine on growth inhibition as well as autophagy in glioma cells in vitro and in vivo. The proliferation of both LN229 and T98 glioma cells, measured by MTT assay, was suppressed in a concentration-dependent and time-dependent manner. Moreover, apoptosis of both cells was significantly increased with the treatment of olanzapine as evidenced by increased Bcl-2 expression, Hoechst 33258 staining and annexinV-FITC/PI staining. Olanzapine treatment also enhanced activation of autophagy with increased expression of LC3-II, expression of protein p62, a substrate of autophagy, being decreased. The growth inhibition by olanzapine in both glioma cell lines could be blocked by co-treatment with 3-MA, an autophagy inhibitor. Furthermore, olanzapine effectively blocked the growth of subcutaneous xenografts of LN229 glioma cells in vivo. The increased level of protein LC3-II and decreased level of p62 followed by a decreased level of Bcl-2, suggesting that autophagy may contribute to apoptosis. In addition, reduced proliferation of glioma cells was shown by a decrease of Ki-67 staining and increased caspase-3 staining indicative of apoptosis in mouse xenografts. These results indicated that olanzapine inhibited the growth of glioma cells accompanied by induction of autophagy and apoptosis both in vitro and in vivo. Olanzapine-induced autophagy plays a tumor-suppressing role in glioma cells.

Double Closed-loop Integral Terminal Sliding Mode for a Class of Underactuated Systems Based on Sliding Mode Observer

Wei Liu,Si-yi Chen,Hui-xian Huang 제어·로봇·시스템학회 2020 International Journal of Control, Automation, and Vol.18 No.2

Aiming to solve the tracking control problem of a class of second-order underactuated mechanical systems with unknown model parts, external disturbances and noise disturbances, a double closed-loop layered integral terminal sliding mode control method based on sliding mode observer is proposed. At the outset, the Lagrange model of the system is transformed into an affine model, and a sliding mode observer is designed according to the system structure. Neatly, the outer loop controller is designed using the observer’s estimated state, and the output value of the outer loop controller is filtered with a low pass filter. Then the inner loop controller is designed by using hierarchical sliding mode control method. On a premise of ensuring tracking performance, the control method can maximally improve convergence speed and reduce chattering even if there are unknown model parts, external interference and noise interference phenomena in the system. This simulation results distinctly display the effectiveness of the control tactics.

Factors that Influence the Presciption of Antipsychotics for Patients with Schizophrenia in China

Tian-Mei Si,Liang Shu,Ke-Qing Li,Xie-He Liu,Qi-Yi Mei,Gao-Hua Wang,Pei-Shen Bai,Li-Ping Ji,Xian-Sheng Chen,Cui Ma,Jian-Guo Shi,Hong-Yan Zhang,Hong Ma,Xin Yu 대한정신약물학회 2011 CLINICAL PSYCHOPHARMACOLOGY AND NEUROSCIENCE Vol.9 No.3

Objective: To investigate the patterns of antipsychotic use in China and to analyze the factors that influence antipsychotic prescriptions. Methods: A standardized survey was conducted from May 20 to 24 2002 in five different regions of China with varying economic levels. The patterns of antipsychotic medication use were analyzed in a sample of 4,779 patients with schizophrenia. The survey gathered information on demographic characteristics, clinical profiles, and antipsychotic medications prescribed. Multiple logistic regression was used to analyze factors related to patterns of antipsychotic medication use. Results: A plurality of patients with schizophrenia was treated with clozapine (39%); this was followed by risperidone, sulpride,chlorpromazine, perphenazine, and haloperidol. More than 56.3% of patients were treated with only one atypical antipsychotic. The mean daily dose of chlorpromazine was 365±253 mg (mean±standard deviation), and 6.5% of patients were treated with depot injections of typical antipsychotic medications. A total of 73.7% (n=3,523) of patients with schizophrenia received monotherapy,24.8% (n=1,183) received two antipsychotics, 1.1% (n=52) received three antipsychotics, and one received four different antipsychotics. Patients often simultaneously received other classes of medications including anticholinergic agents, benzodiazepines,β-blockers, antidepressants, and mood stabilizers. Economic status and clinical symptoms were the main factors that contributed to the patterns of antipsychotic prescription. Conclusion: The present study suggests that atypical antipsychotic medications, especially clozapine, are the primary psychiatric treatments of choice in the management of schizophrenia in China. Moreover, the economic status and clinical profile of the patient are the major factors affecting the prescription of antipsychotic medication.

Status and Determinants of Health Literacy among Adolescents in Guangdong, China

Ye, Xiao-Hua,Yang, Yi,Gao, Yan-Hui,Chen, Si-Dong,Xu, Ya Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.20

Background: Previous studies for non-communicable disease cotrol, including cancer, have mostly relied on health literacy in adults. However, limited studies are available for adolescents. This study aimed to assess the status and determinants of health literacy in in-school adolescents in Guangdong, China. Materials and Methods: A total of 3,821 students aged 13-25 years were selected by multi-stage cluster sampling. After the questionnaire of health literacy was answered, the total scores for health knowledge (18 questions), skills (5 questions) and behaviors (14 questions) were determined. The total scores for health literacy and each subscale were recoded into adequate and inadequate subgroups, and logistic regression models were used to identify factors associated with each outcome variable. Results: The prevalence of adequate health literacy was 14.4%, and the prevalences for adequate knowledge, skills and behavior were 22.4%, 64.7% and 6.6%, respectively. Students coming from prestigious schools and having parents with higher education had higher odds of having adequate knowledge, skills and behaviors. Female students had higher odds of having adequate knowledge and behaviors. Students in grade 7-8 had higher odds of having adequate knowledge and skills. The health knowledge was positive associated with health skills (odds ratio [OR] =2.1, 95% confidence interval [CI] 1.7-2.5) and behaviors (OR=3.0, 95%CI 2.3-4.0), and health skills were positive associated with health behaviors (OR=2.6, 95%CI 1.8-3.8). Conclusions: Further efforts should be made to increase adolescents' health knowledge and behaviors, especially for low grade and male students in non-prestigious schools.

Mutations of TYR and MITF Genes are Associated with Plumage Colour Phenotypes in Geese

Wang, Ye,Li, Si-Ming,Huang, Jing,Chen, Shi-Yi,Liu, Yi-Ping Asian Australasian Association of Animal Productio 2014 Animal Bioscience Vol.27 No.6

The polymorphism of microphthalmia-associated transcription factor (MITF) and tyrosinase (TYR) genes have been proposed to play a vital role in coat colour genesis in mammals, but their role remains ambiguous in geese at best. Here, we cloned and sequenced 1,397 bp coding region of MITF gene and a 588 bp fragment of TYR exon 1 for polymorphism analysis among 157 domestic geese showing three types of plumage colour. We detected a total of three SNPs (c.280T>C, c.345G>A, and c.369G>A) in TYR and six haplotypes (H1-H6). Among them, haplotypes H1, H2, H3, and H5 were significantly associated with white plumage trait of Zhedong White Geese. However, only diplotype H1H1 and H3H5 were significantly associated with white plumage trait of Zhedong White Geese (p<0.01). We only detected one SNP (c.1109C>T) for MITF gene and found that genotype CT and TT were significantly associated with white plumage trait of Zhedong White Geese. Briefly, our study suggested an association between polymorphisms of TYR and MITF genes and the plumage colour trait in domestic geese.