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Dynamic expression of apoptosis-related genes during development of laboratory hepatocellular carcinoma and its relation to apoptosis

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World Journal of Gastroenterology 2005年第30期11卷 4740-4744页

作者： Xiao-Xian Duan Jing-Sheng Ou Yuan Li Jian-Jia Su Chao Ou Chun Yang Hui-fen yue Ke-chen Ban Department of Pathology Affiliated Tumor Hospital of Guangxi Medical University Laboratory Center of Medical Sciences of Guangxi Medical University Nanning 530021 Guangxi Zhuang Autonomous Region China

AIM： To explore the expression of p53, bcl-2, bax, survivin and the cell apoptosis during the development of tree shrew hepatocellular carcinoma （HCC）, the relationship between expression of these genes, its impact on HCC development, and its relation to cell apoptosis. METHODS： Tree shrew HCC was induced with aflatoxin B1 （AFB1）, and regular biopsy of liver tissues was carried out and the biopsy tissues were collected during cancer inducement. Liver biopsy tissue and HCC tissue were collected from 35 pre-cancerous experimental animals at wk 30 and 60 and at the 30^th, 60^th, and 90^th -wk. Liver biopsy tissues were collected from 13 blank control animals at wk 30, 60, and 90. Expression of p53, bcl-2, bax, and survivin at each stage was examined by immunohistochemistry method. Apoptotic cells were detected in situ by the terminal deoxynucleotidyl transferase-mediated nick end labeling （TUNEL） technique. RESULTS： The apoptosis rate of normal hepatic cells was extremely low, whereas it increased during the formation of HCC. Expression of the apoptosis-related genes p53, bcl-2, bax, and survivin during the formation of HCC presented an increasing tendency. Expression of p53 did not noticeably relate to that of bcl-2, bax, and survivin, whereas expression of bcl-2 and bax was closely related. In HCC, p53 did not present a distinct relation to cell apoptosis, whereas its high level expression was probably related to liver cell proliferation. Survivin negatively correlated apoptosis index, and its overexpression could inhibit cell apoptosis. CONCLUSION： Apoptosis-related genes p53, bcl-2, bax, and survivin are all related to the occurrence of HCC. The anti-apoptosis effect of bcl-2 is influenced by bax, and ratio bcl/bax reflects more correctly the extent of cell apoptosis.

关键词： Hepatocellular carcinoma Apoptosis Gene

Fault Estimation for a Class of Markov Jump Piecewise-Affine Systems: Current Feedback Based Iterative Learning Approach

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IEEE/CAA Journal of Automatica Sinica 2024年第2期11卷 418-429页

作者： Yanzheng Zhu Nuo Xu fen Wu Xinkai chen Donghua Zhou IEEE College of Electrical Engineering and Automation Shandong University of Science and TechnologyQingdao 266590China College of Mechanical Engineering and Automation Huaqiao UniversityXiamen 361021China Department of Mechanical and Aerospace Engineering North Carolina State UniversityRaleigh NC 27695 USA Department of Electronic and Information Systems Shibaura Institute of TechnologySaitama 337-8570Japan

In this paper, the issues of stochastic stability analysis and fault estimation are investigated for a class of continuoustime Markov jump piecewise-affine(PWA) systems against actuator and sensor faults. Firstly, a novel mode-dependent PWA iterative learning observer with current feedback is designed to estimate the system states and faults, simultaneously, which contains both the previous iteration information and the current feedback mechanism. The auxiliary feedback channel optimizes the response speed of the observer, therefore the estimation error would converge to zero rapidly. Then, sufficient conditions for stochastic stability with guaranteed performance are demonstrated for the estimation error system, and the equivalence relations between the system information and the estimated information can be established via iterative accumulating ***, two illustrative examples containing a class of tunnel diode circuit systems are presented to fully demonstrate the effectiveness and superiority of the proposed iterative learning observer with current feedback.

关键词： Current feedback fault estimation iterative learning observer Markov jump piecewise-affine system

Dual-Defect Engineering Strategy Enables High-Durability Rechargeable Magnesium-Metal Batteries

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Nano-Micro Letters 2024年第9期16卷 449-461页

作者： Fuyu chen Bai‑Qing Zhao Kaifeng Huang Xiu‑fen Ma Hong‑Yi Li Xie Zhang Jiang Diao Jili yue Guangsheng Huang Jingfeng Wang Fusheng Pan National Innovation Center for Lndustry‑Education Integration of Energy Storage Technology School of Materials Science and EngineeringChongqing UniversityChongqing 400044People’s Republic of China National Magnesium Alloy Material Engineering Technology Research Center Chongqing UniversityChongqing 400044People’s Republic of China Materials and Energy Division Beijing Computational Science Research CenterBeijing 100193People’s Republic of China School of Materials Science and Engineering Northwestern Polytechnical UniversityXi’an 710072People’s Republic of China National Key Laboratory of Advanced Casting Technologies Chongqing UniversityChongqing 400044People’s Republic of China

Rechargeable magnesium-metal batteries(RMMBs)are promising next-generation secondary batteries;however,their development is inhibited by the low capacity and short cycle lifespan of *** various strategies have been devised to enhance the Mg^(2+)migration kinetics and structural stability of cathodes,they fail to improve electronic conductivity,rendering the cathodes incompatible with magnesium-metal ***,we propose a dual-defect engineering strategy,namely,the incorporation of Mg^(2+)pre-intercalation defect(P-Mgd)and oxygen defect(Od),to simultaneously improve the Mg^(2+)migration kinetics,structural stability,and electronic conductivity of the cathodes of *** lamellar V_(2)O_(5)·nH_(2)O as a demo cathode material,we prepare a cathode comprising Mg_(0.07)V_(2)O_(5)·1.4H_(2)O nanobelts composited with reduced graphene oxide(MVOH/rGO)with P-Mgd and *** Od enlarges interlayer spacing,accelerates Mg^(2+)migration kinetics,and prevents structural collapse,while the P-Mgd stabilizes the lamellar structure and increases electronic ***,the MVOH/rGO cathode exhibits a high capacity of 197 mAh g^(−1),and the developed Mg foil//MVOH/rGO full cell demonstrates an incredible lifespan of 850 cycles at 0.1 A g^(−1),capable of powering a light-emitting *** proposed dual-defect engineering strategy provides new insights into developing high-durability,high-capacity cathodes,advancing the practical application of RMMBs,and other new secondary batteries.

关键词： Rechargeable magnesium-metal batteries Dual-defect engineering Vanadium-based cathode High durability Lamellar structure

On convergence of covariance matrix of empirical Bayes hyper-parameter estimator

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Control Theory and Technology 2024年第2期22卷 149-162页

作者： yue Ju Biqiang Mu Tianshi chen School of Data Science and Shenzhen Research Institute of Big Data The Chinese University of Hong KongShenzhenShenzhen518172GuangdongChina Division of Decision and Control Systems School of Electrical Engineering and Computer ScienceKTH Royal Institute of Technology10044StockholmSweden Key Laboratory of Systems and Control Institute of Systems ScienceAcademy of Mathematics and System ScienceChinese Academy of SciencesBeijing100190China

Regularized system identification has become the research frontier of system identification in the past *** related core subject is to study the convergence properties of various hyper-parameter estimators as the sample size goes to *** this paper,we consider one commonly used hyper-parameter estimator,the empirical Bayes(EB).Its convergence in distribution has been studied,and the explicit expression of the covariance matrix of its limiting distribution has been ***,what we are truly interested in are factors contained in the covariance matrix of the EB hyper-parameter estimator,and then,the convergence of its covariance matrix to that of its limiting distribution is *** general,the convergence in distribution of a sequence of random variables does not necessarily guarantee the convergence of its covariance ***,the derivation of such convergence is a necessary complement to our theoretical analysis about factors that influence the convergence properties of the EB hyper-parameter *** this paper,we consider the regularized finite impulse response(FIR)model estimation with deterministic inputs,and show that the covariance matrix of the EB hyper-parameter estimator converges to that of its limiting ***,we run numerical simulations to demonstrate the efficacy of ourtheoretical results.

关键词： Regularized system identification Hyper-parameter estimator Empirical Bayes Convergence of covariance matrix

Polyolefin vitrimers bearing acetoacetate functionality

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Science China Chemistry 2024年第11期67卷 3861-3867页

作者： Zihao Wang yue Liu Wenmin Pang Ao chen Min chen Chinese Academy of Sciences (CAS) Key Laboratory of Soft Matter Chemistry Department of Polymer Science and Engineering University of Science and Technology of China Institutes of Physical Science and Information Technology Key Laboratory of Structure and Functional Regulation of Hybrid Materials of Ministry of Education Anhui University

Polyolefin vitrimers are polymer networks bearing reversible covalent crosslinking points, enabling them to be reprocessed and recycled. In this contribution, a series of polyolefin vitrimers were designed based on the acetoacetate-functionalized polyolefin copolymers, which were produced through the direct copolymerization of ethylene with polar comonomers using a phosphinesulfonate palladium catalyst. The pendant acetoacetate group could mediate several characteristic reactions, such as the Michael addition reaction, ketone-amine condensation and metal coordination reaction. As such, structurally adjustable polyolefin vitrimers can be accessed by introducing various dynamic crosslinking bonds, including disulfide exchange, transamination of vinylogous urethane and labile metal coordination bond. The utilization of different crosslinking reactions and the mole ratio of crosslinkers significantly impact the material properties of the resultant polymers. Specifically, the generated polyolefin vitrimers demonstrated excellent reprocessability and closed-loop recycling properties. The study in this work provides an efficient strategy to access various polyolefin vitrimers.

关键词： polyolefin vitrimers acetoacetate group polar monomer olefin copolymerization

Self-powered and self-sensing devices based on piezoelectric energy harvesting

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Science China(Technological Sciences) 2024年第6期67卷 1631-1667页

作者： chen GanTong ZHU yue HUANG DongMei ZHOU ShengXi School of Aeronautics Northwestern Polytechnical UniversityXi’an710072China School of Mathematics and Statistics Xidian UniversityXi’an710071China

Wearable devices,interactive human-machine interface equipment,wireless sensors,and small-scale cleaning devices play crucial roles in biomedical implantation,disease treatment,health monitoring,environmental purification,*** devices require a sustainable energy source to work *** the consideration of the global energy crisis and environmental pollution,researchers are exploring new,stable,and environmentally friendly methods to power these low-powered *** energy is one of the most abundant natural energy *** mechanical energy from the ambient environment or host structures into electrical energy via the direct piezoelectric effect is an efficient energy harvesting *** paper reviews the application of advanced piezoelectric materials,and small-scale self-powered and self-sensing piezoelectric devices at the cubic centimeter scale in energy harvesting and health monitoring of human,animal,machinery,roads,bridges,as well as the pollutant degradation of the *** of these devices have the capability to not only harvest mechanical energy but also enable real-time monitoring and analysis of the electrical signals generated by the direct piezoelectric effect,facilitating prompt decision-making and appropriate *** addition,potential challenges and future prospects of small-scale self-powered and self-sensing piezoelectric devices are discussed.

关键词： piezoelectric energy harvesting self-powered self-sensing wearable devices implantable devices

Simulation of roof snow loads based on a multi-layer snowmelt model:Impact of building heat transfer

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Building Simulation 2024年第6期17卷 907-932页

作者： Xuanyi Zhou Heng chen yue Wu Tiange Zhang State Key Laboratory of Disaster Reduction in Civil Engineering Tongji UniversityShanghai200092China

To investigate the impact of building heat transfer on roof snow loads,roof snow loads and snow load thermal coefficients from 61 Chinese sites over a period of 50 years are simulated based on basic meteorological data such as temperature,humidity,wind speed,and precipitation,and a multi-layer snowmelt model considering the building heat ***,the accuracy of the multi-layer snowmelt model is validated using the data of observed ground snow load and roof snow melting *** relationship between meteorological conditions,snow cover characteristics,and thermal coefficients of snow loads in three representative sites is then ***,the characteristics of thermal coefficients in each zone are analyzed by combining them with the statistical results of meteorological data from 1960 to 2010,and the equations of thermal coefficients in different zones on indoor temperatures and roof heat transfer coefficients are fitted ***,the equations in this paper are compared with the thermal coefficients in the main snow load *** results indicate that the snowmelt model using basic meteorological data can effectively provide samples of roof snow *** the cold zone where the snow cover lasts for a long time and does not melt easily,the thermal coefficients of the snow loads on the heating buildings are lower than those in the warm zone due to the long-term influence of the heat from inside the *** coefficients are negatively correlated with indoor temperatures and roof heat transfer *** the indoor temperature is too low or the roof insulation is good,the roof snow load may exceed the ground snow *** thermal coefficients for heated buildings in the main snow load codes are more conservative than those calculated in this paper,and the thermal coefficients for buildings with lower indoor temperatures tend to be smaller.

关键词： snowmelt model roof snow load building heat transfer thermal coefficient load code

Mechanical Performance of Bio-inspired Bidirectional Corrugated Sandwich Pressure Shell Under External Hydrostatic Pressure

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China Ocean Engineering 2024年第2期38卷 297-312页

作者： ZHANG Yi chen yue YUN Lai LIANG Xu Ocean College Zhejiang UniversityZhoushan 316000China Hainan Institute Zhejiang UniversitySanya 572000China

This paper aims to enhance the compression capacity of underwater cylindrical shells by adopting the corrugated sandwich structure of *** cuttlebone suffers uniaxial external compression,while underwater cylindrical shells are in a biaxial compressive stress *** suit the biaxial compressive stress state,a novel bidirectional corrugated sandwich structure is proposed to improve the bearing capacity of cylindrical *** static and buckling analysis for the sandwich shell and the unstiffened cylindrical shell with the same volume-weight ratio are studied by numerical *** is indicated that the proposed sandwich shell can effectively reduce the ratio between circumferential and axial stress from 2 to 1.25 and improve the critical buckling load by about 1.63 *** simulation shows that optimizing and adjusting the structural parameters could significantly improve the advantage of the sandwich ***,the hydrostatic pressure tests for shell models fabricated by 3D printing are carried *** to the experimental results,the overall failure position of the sandwich shell is at the center part of the sandwich *** has been found the average critical load of the proposed sandwich shell models exceeds two times that of the unstiffened shell ***,the proposed bio-inspired bidirectional corrugated sandwich structure can significantly enhance the pressure resistance capability of cylindrical shells.

关键词： bio-inspiration bidirectional corrugation sandwich shell external pressure buckling

Adverse effects of exposure to fine particles and ultrafine particles in the environment on different organs of organisms

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Journal of Environmental Sciences 2024年第1期135卷 449-473页

作者： Jianwei Zhang Zhao chen Dan Shan Yang Wu yue Zhao chen Li yue Shu Xiaoyu Linghu Baiqi Wang Department of Occupational and Environmental Health School of Public HealthTianjin Medical UniversityTianjin 300070China Department of Medical Tianjin Stomatological HospitalSchool of MedicineNankai UniversityTianjin 300041China Tianjin Key Laboratory of Environment Nutrition and Public HealthTianjin 300070China National Demonstration Center for Experimental Preventive Medicine Education(Tianjin Medical University) Tianjin 300070China

Particulate pollution is a global risk factor that seriously threatens human *** particles(FPs)and ultrafine particles(UFPs)have small particle diameters and large specific surface areas,which can easily adsorb metals,microorganisms and other *** and UFPs can enter the human body in multiple ways and can be easily and quickly absorbed by the cells,tissues and *** the body,the particles can induce oxidative stress,inflammatory response and apoptosis,furthermore causing great adverse *** studies mainly take the population as the research object to study the distribution of diseases and health conditions in a specific population and to focus on the identification of influencing ***,the mechanism by which a substance harms the health of organisms is mainly demonstrated through toxicological *** epidemiological studies with toxicological studies will provide a more systematic and comprehensive understanding of the impact of PM on the health of *** this review,the sources,compositions,and morphologies of FPs and UFPs are briefly introduced in the first *** effects and action mechanisms of exposure to FPs and UFPs on the heart,lungs,brain,liver,spleen,kidneys,pancreas,gastrointestinal tract,joints and reproductive system are systematically *** addition,challenges are further pointed out at the end of the *** work provides useful theoretical guidance and a strong experimental foundation for investigating and preventing the adverse effects of FPs and UFPs on human health.

关键词： Fine particles Ultrafine particles Organs Adverse effect