Intestinal mucus components and secretion mechanisms: what we do and do not know

Song Chunyan,Chai Zhenglong,Chen Si,Zhang Hui,Zhang Xiaohong,Zhou Yuping 생화학분자생물학회 2023 Experimental and molecular medicine Vol.55 No.-

Damage to the colon mucus barrier, the first line of defense against microorganisms, is an important determinant of intestinal diseases such as inflammatory bowel disease and colorectal cancer, and disorder in extraintestinal organs. The mucus layer has attracted the attention of the scientific community in recent years, and with the discovery of new mucosal components, it has become increasingly clear that the mucosal barrier is a complex system composed of many components. Moreover, certain components are jointly involved in regulating the structure and function of the mucus barrier. Therefore, a comprehensive and systematic understanding of the functional components of the mucus layer is clearly warranted. In this review, we summarize the various functional components of the mucus layer identified thus far and describe their unique roles in shaping mucosal structure and function. Furthermore, we detail the mechanisms underlying mucus secretion, including baseline and stimulated secretion. In our opinion, baseline secretion can be categorized into spontaneous Ca2+ oscillation-mediated slow and continuous secretion and stimulated secretion, which is mediated by massive Ca2+ influx induced by exogenous stimuli. This review extends the current understanding of the intestinal mucus barrier, with an emphasis on host defense strategies based on fortification of the mucus layer.

Optimal Control and Stabilization for Discrete-time Markov Jump Systems With Indefinite Weight Costs and Multi-channel Multiplicative Noises

Song Zhang,Chunyan Han,Wei Wang 제어·로봇·시스템학회 2023 International Journal of Control, Automation, and Vol.21 No.7

This paper is concerned with the optimal control and stabilization problems for discrete-time Markov jump systems with multi-channel multiplicative noises. The weight matrices in the cost function can be indefinite. The necessary and sufficient existence conditions for the optimal controller in the finite horizon is proposed explicitly in terms of generalized difference Riccati equations. Further, via the finite horizon optimal cost, we define a Lyapunov function to reduce the indefinite stabilization problem to a definite one. And in the infinite horizon, the necessary and sufficient condition to stabilize the Markov jump linear system in the mean-square sense is presented. Moreover, we prove that the Markov jump linear system is mean-square stabilizable if and only if the generalized coupled algebraic Riccati equation has a solution. Simultaneously, this solution is the maximal solution to the generalized coupled algebraic Riccati equations.

Water Evaporation-Induced Self-Assembly of Hierarchical CuO/MnO2 Composite Nanospheres and their Applications in Lithium-Ion Batteries

Chunyan Zeng,Chen Gao,Li Yuan,Tao Liang,Ruisong Yang,Wei Zhang,Song Nie 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2017 NANO Vol.12 No.2

In this paper, hierarchical CuO/MnO2 composite hollow nanospheres have been successfully fabricated by water evaporation-induced self-assembly through a redox transformation reaction between Cu2O nanospheres and KMnO4 solution at 120℃ for 6 h, followed by removing the residual Cu2O cores with ammonia hydroxide solution. The outstanding feature of this method is that the reaction system is in a dynamic environment due to the evaporation of the solvent water, which benefits the self-assembly of nanostructures to form hierarchical structures. Both Kirkendall effect and Ostwald ripening mechanism are suggested to be responsible for the formation of the hierarchical CuO/MnO2 nanocomposites according to the characterization results. The electrochemical properties of the products were studied, and the results show that the hierarchical CuO/MnO2 hollow nanospheres exhibit high capacity and good rate performance (a stable capacity of about 480 mAh g-1 after 80 cycles of variable charging rate), which is probably attributed to the hierarchical hollow nanostructures.

Soluble Axl Is a Novel Diagnostic Biomarker of Hepatocellular Carcinoma in Chinese Patients with Chronic Hepatitis B Virus Infection

Xiaoting Song,Ailu Wu,Zhixiao Ding,Shixiong Liang,Chunyan Zhang 대한암학회 2020 Cancer Research and Treatment Vol.52 No.3

Purpose The purpose of this study was to evaluate the diagnostic value of soluble Axl (sAxl) in hepatocellular carcinoma (HCC) in comparison with serum "-fetoprotein (AFP). Materials and Methods Eighty HCC patients, 80 liver cirrhosis patients (LC), 80 patients with hepatitis B virus (HBV) infection, and 80 healthy controls (HC) were enrolled. sAxl levels were measured by an enzyme-linked immunosorbent assay, serum AFP levels were measured by an electrochemiluminescence immunoassay. Receiver operating characteristic (ROC) curves were used to evaluate diagnostic performances. Results The results show that levels of sAxl were high expression in patients with HCC (p < 0.05), varied with disease state as follows: HCC > LC > HC > HBV. Logistic regression and ROC curve analysis identified the optimal cut-off for sAxl in differentiating all HCC and non-HCC patients was 1,202 pg/mL (area under the receiver operating characteristic [AUC], 0.888; 95% confidence interval [CI], 0.852 to 0.924) with sensitivity 95.0%, specificity 73.3%. Furthermore, differential diagnosis of early HCC with non-HCC patients for sAxl showed the optimal cut-off was 1,202 pg/mL (AUC, 0.881; 95% CI, 0.831 to 0.931; sensitivity, 94.1%; specificity, 73.3%). Among AFP-negative HCC patients with non-HCC patients, the cut-off was 1,301 pg/mL (AUC, 0.898; 95% CI, 0.854 to 0.942) with a sensitivity of 84.6%, a specificity of 76.3%. The optimal cut-off for sAxl in differentiating all HCC and chronic liver disease patients was 1,243 pg/mL (AUC, 0.840; 95% CI, 0.791 to 0.888) with sensitivity 93.8%, specificity 61.9%. The combination of AFP and sAxl increased diagnostic value for HCC. Conclusion sAxl outperforms AFP in detecting HCC, especially in early HCC and in AFP-negative HCC. Combination sAxl with AFP improved the specificity for early HCC diagnosis. In summary, sAxl is a candidate serum marker for diagnosing HCC.

Preparation and properties of coated silica/aluminum cermet materials via powder metallurgy method

Jieguang Song,Yue Liu,Chunxiao Wu,Xueqing Yang,Huihui Luo,Chunyan He,Chengbin Li,Haizhen Yang 한양대학교 세라믹연구소 2020 Journal of Ceramic Processing Research Vol.21 No.2

Cermet is a combination of metal and ceramic, it exhibits some special properties, so it is one of the most widely usedengineering materials. In this paper, the properties of encapsulated SiO2/Al cermet were prepared by powder metallurgymethod. Results showed that the density of SiO2/Al cermet is increased with an increasing Al content. When the Al contentis high, and the high temperature is sintered, the liquid phase can fully bond the surrounding SiO2 particles to form a relativelycontinuous and dense structure, thereby obtaining a high microstructure density. When the SiO2:Al ratio is increased from 1:1to 1:3, the hardness is gradually increased. The hardness and density of the sample are gradually increased with an increasingmolding pressure. The surface hardness of the cermet is increased first and then decreased with an increasing sinteringtemperature. When the SiO2:Al ratio is 1:3, the holding time is 10 min under molding pressure of 15 MPa, and the sinteringtemperature is 900 °C for 1 h, the surface hardness of the obtained coated SiO2/Al cermet is high, the value is 175.2 HV.

Fabrication and properties of Al2O3-Al cermet materials using different raw material composition parameter

Jieguang Song,Yue Liu,Chunxiao Wu,Xueqing Yang,Yipeng Gong,Jianzhen Huang,Chunyan He,Huihui Luo,Aixia Chen 한양대학교 세라믹연구소 2020 Journal of Ceramic Processing Research Vol.21 No.1

Cermet application is extensive because it retains the characteristics of ceramic materials and has the advantages of metalmaterials. In this paper, alumina/aluminum cermet materials were prepared through powder metallurgy method. Theinfluence of raw material formula on the properties of alumina/aluminum cermet was investigated on the basis that ceramicmaterials have good wear resistance and high thermal conductivity. Results show that when the mass ratio of alumina toaluminum is 1:3, the prepared cermet samples have excellent properties, highest density, and uniform distribution ofaluminum and alumina. MgO addition exhibits better effect, higher degree of densification, and renders higher hardness andstrength for the sample as compared with SiO2 and Y2O3 addition. The sintered cermet with composite powder prepared viaprecipitation has better properties and higher densities and surface hardness than that prepared via the ball mill method. Therelative density was 97.1%, surface hardness was 875 HV, and electric resistance was 0.0169 Ω·m.

Operational Risk Management of Commercial Banks

Jianbo Song,Xiaokun Zhao,Chunyan Sheng 인하대학교 정석물류통상연구원 2009 인하대학교 정석물류통상연구원 학술대회 Vol.2009 No.10

In this paper, we present the types and characteristics of risks in commercial banks. Among all the risks, operational risk is paid more and more heed to. It is caused by people, processes, external events and other factors. According to the Base II New Capital Accord, there are mainly three approahces to the capital for dperational risk-The Basic Indicator Approach, The Standardized Approach and The Advanced Measurement Approach. We can take actions to manage the operational risk in commerical banks and improve their competitiveness: (1) create a culture of risk management; (2) establish the independent organizational structure of risk management; (3) introduce the strict division of posts; (4) design a procedure of tight authorization; (5) assume the procedural or standardized control; (6) set up the efficient program of employee management; (7) reengineer the business processes of banks; (8) highlight control over special risk points.

The Philosophical Thinking of the World University Games

( Haiyan Zhao ),( Song Ma ),( Chunyan Li ) 한국체육학회 2015 국제스포츠과학 학술대회 Vol.2015 No.1

Through studying the teleology, subject theory and methodology of the World University Games, this research topic aims to analyze the current orientation of development, subject of development and mode of development and appeal for setting objectives, grasping the significance of subject and improving the mechanism of competition in modern world university games in order to rebuild a sound image of world university games.

Life-Cycle Economic Evaluation of Batteries for Electeochemical Energy Storage Systems

Zhang Donghao,Cai Xiangyu,Song Chunyan,Liu Jie,Ding Jia,Zhong Cheng,Hu Wenbin 대한전기학회 2021 Journal of Electrical Engineering & Technology Vol.16 No.5

Batteries are considered as an attractive candidate for grid-scale energy storage systems (ESSs) application due to their scalability and versatility of frequency integration, and peak/capacity adjustment. Since adding ESSs in power grid will increase the cost, the issue of economy, that whether the benefi ts from peak cutting and valley fi lling can compensate for the cost input of adding energy storage system or not, is particularly concerned. Here we show how the cost of battery deployment can potentially be minimized by carrying out an economic assessment for the cases of diff erent batteries applied in ESSs. To make this analysis, we develop a techno-economic model and apply it to the cases of ESSs with batteries in applications. Our results show that batteries could be attractive for investors even now if appropriate batteries are selected for ESSs applications. Valve regulated lead acid batteries has a lower cost of initial investment, which is suitable for the situations that are sensitive to the initial investment cost. Lithium iron phosphate (LiFePO 4 , LFP) battery can be applied in the situations with a high requirement for service life. While zinc-air batteries still have great application prospects to cope with resource depletion due to excellent performance, low cost and low pollution. The current policy debate should therefore be refocused so as to promote technological development and to encompass the removal of such barriers.

The Effect of Font Type and Font Size on the Legibility in Smart Watch Usage of the Elderly People

Na Kyoung You,Minjee Kim,Chunyan Shan,SungYub Kim,Jungyoon Song,Sangmin Yeo,Donghyun An,Myung Hwan Yun 대한인간공학회 2017 대한인간공학회 학술대회논문집 Vol.2017 No.11

Objective: The aim of this study is to investigate the effect of character size and font type on legibility of elderly in smart watch usage, and to suggest a design guideline for smart watch - dedicated for legibility enhancement of the elderly people. Background: As the elderly population increases, the demand for health care and relevant costs for elderly are increasing correspondingly. Hence, there have been researches to implement wearable device onto the health monitoring system for elderly. In such manner, smart watch is one of the wearables popularly studied. However, poor legibility due to the small display of smart watch is considered to be a problem for the elderly to fully use it. Thus, legibility should be improved to allow elderly to use the smart watch more conveniently. Method: The task of selecting a target stimulus within two simultaneously given stimuli on a smart watch display was given to participants. A total of 10 sets of stimuli was given, and they were in combination of single font size and type. All subjects performed the task for a total of 8 stimuli sets combining 4 font sizes and 2 font types. The dependent variable is the time to select stimulus and the error occurrence frequency: the number of interference stimulus chosen. Results and Conclusions: In Gothic type, there was no significant differences in recognition time between font sizes. However, in the case of Myung, 9pt, 10pt is better than 11pt, and 12pt. In the case of error frequency, it is shown that 10pt and 11pt results better compared to other two font sizes in case of Gothic. There was no difference in Myung. Application: The results of the study can be the useful guideline to improve legibility for the elderly.