Metallothionein MT1M Suppresses Carcinogenesis of Esophageal Carcinoma Cells through Inhibition of the Epithelial-Mesenchymal Transition and the SOD1/PI3K Axis

Li, Dandan,Peng, Weiyan,Wu, Bin,Liu, Huan,Zhang, Ruizhen,Zhou, Ruiqin,Yao, Lijun,Ye, Lin Korean Society for Molecular and Cellular Biology 2021 Molecules and cells Vol.44 No.4

Metallothionein (MT1M) belongs to a family of cysteinerich cytosolic protein and has been reported to be a tumor suppressor gene in multiple cancers. However, its role in esophageal carcinoma carcinogenesis remains unclear. In this study, MT1M expression was correlated with tumor type, stage, drinking and smoking history, as well as patient survival. We also studied the regulation and biological function of MT1M in esophageal squamous cell carcinoma (ESCC). We have found that MT1M is significantly downregulated in ESCC tissues compared with adjacent non-cancer tissues. Furthermore, restoration of expression by treatment with the demethylation agent A + T showed that MT1M downregulation might be closely related to hypermethylation in its promoter region. Over-expression of MT1M in ESCC cells significantly altered cell morphology, induced apoptosis, and reduced colony formation, cell viability, migration and epithelial-mesenchymal transition. Moreover, based on reactive oxygen species (ROS) levels, a superoxide dismutase 1 (SOD1) activity assay and protein analysis, we verified that the tumor-suppressive function of MT1M was at least partially caused by its upregulation of ROS levels, downregulation of SOD1 activity and phosphorylation of the SOD1 downstream pathway PI3K/AKT. In conclusion, our results demonstrated that MT1M was a novel tumor-suppressor in ESCC and may be disrupted by promoter CpG methylation during esophageal carcinogenesis.

Unified model for the output accuracy of open-chain manipulators that considers joint clearance and structural parameters

Shuwei Qu,Ruiqin Li,Shaoping Bai,Shijie Liang 대한기계학회 2018 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.32 No.10

A unified model is proposed for the output accuracy of open-chain manipulators in consideration of joint clearance and structural parameters. First, the operator of the finite-displacement screw matrix and the combination operation are presented. Second, the joint clearance and structural parameters are described and analyzed with screw theory. A virtual screw is established for the joint clearance and structural parameter errors. Third, a unified model is built through the adjoint transformation of Lie groups in consideration of the two effectors of the virtual screw. The error pose is decomposed into orientation and position errors, which are obtained through the virtual screw. Finally, an open-chain manipulator with six degrees of freedom is analyzed based on the proposed model. The position and orientation errors are obtained with the trajectory that provided an intuitive geometric insight into the accuracy and exact maximal position and orientation errors.

Concept Optimization for Mechanical Product Using Ant Colony System

Ruifeng Bo,Ruiqin Li,Hongxia Pan 대한기계학회 2008 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.22 No.4

The aim of conceptual design is to generate the best design candidate. Concept solving in conceptual design can be viewed as a problem of combinatorial optimization, in which there exists a “combinational explosion” phenomenon when using the traditional morphological matrix method to tackle it. In this research, a concept optimization problem is studied based on an Ant Colony System (ACS). By analyzing the similarity between concept solving and Traveling Salesman Problem (TSP), concept solving is transformed into a problem of optimal path in combinatorial optimization, where the dynamic programming based solution space model and the longest path based optimization model are developed. Then, the ant algorithm to resolve TSP is adopted to implement concept optimization according to the positive feedback searching mechanism of ACS, and some improvements are made incorporating crossover and mutation operators of a genetic algorithm (GA), to obtain the optimal scheme rapidly and effectively. Finally, a conceptual design case of press is given to demonstrate the feasibility and rationality of this proposed approach. The employment of ACS enables concept solving to be implemented with an algorithm and thus possesses better operability, which offers a promising way to solve the “combinatorial explosion” problem in conceptual design.

Type synthesis for lower-mobility decoupled parallel mechanism with redundant constraints

Shuwei Qu,Ruiqin Li,Chunsheng Ma,Hong Li 대한기계학회 2021 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.35 No.6

A novel method for type synthesis of lower-mobility decoupled parallel mechanism with redundant constraints is proposed. Firstly, the definition of the redundant constraints is put forward. Then, number and topology structure synthesis is carried out based on the redundant constraints between the closed loop structure of parallel configuration. Next, the specific procedure for type synthesis of lower-mobility decoupled parallel mechanism is derived. Furthermore, the local freedom of the limbs was established through the relationship of motion-screw and constraint-screw between limbs. Finally, type synthesis of 2R1T decoupled parallel mechanism is established. The synthesized configuration theoretical output characteristics is a decoupled Jacobin matrix. The output characteristics are analyzed based on theoretical calculation and ADAMS simulation software. The simulation results and the theoretical calculation results are consistent. The proposed method can be applied to type synthesis of lower-mobility decoupled parallel mechanisms.

DPW-RRM: Random Routing Mutation Defense Method Based on Dynamic Path Weight

Hui Jin,Zhaoyang Li,Ruiqin Hu,Jinglei Tan,Hongqi Zhang 한국인터넷정보학회 2023 KSII Transactions on Internet and Information Syst Vol.17 No.11

Eavesdropping attacks have seriously threatened network security. Attackers could eavesdrop on target nodes and link to steal confidential data. In the traditional network architecture, the static routing path and the important nodes determined by the nature of network topology provide a great convenience for eavesdropping attacks. To resist monitoring attacks, this paper proposes a random routing mutation defense method based on dynamic path weight (DPW-RRM). It utilizes network centrality indicators to determine important nodes in the network topology and reduces the probability of important nodes in path selection, thereby distributing traffic to multiple communication paths, achieving the purpose of increasing the difficulty and cost of eavesdropping attacks. In addition, it dynamically adjusts the weight of the routing path through network state constraints to avoid link congestion and improve the availability of routing mutation. Experimental data shows that DPW-RRM could not only guarantee the normal algorithmic overhead, communication delay, and CPU load of the network, but also effectively resist eavesdropping attacks.

Study on morphology and photoluminescence of Au/SiO2 nanocomposite films

Aichun Yang,Yuguo Li,Boshi Zhuo,Ruiqin Peng,Xuelei Zheng 한국물리학회 2012 Current Applied Physics Vol.12 No.1

Au/SiO2 nanocomposite films were fabricated on Si (111) substrates by radio frequency (RF) magnetron sputtering technique and annealing at different temperature for 20 min (mode A) and at 1000℃ for different annealing time (mode B). The nanocomposite films were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD) and photoluminescence (PL). SEM results demonstrate that the size of Au crystallites in mode A first increases and then decreases, on increasing annealing temperature, according to the results of XRD spectra. Analysis of PL spectra in mode B shows that the intensity of the emission peak at 440 nm and 523 nm early increases and late decreases, with increasing annealing time at 1000℃. The origin of the emission peak at around 440 nm was related to the size and quantity of Au particles and one of the emission peak at around 523 nm was related to the nanostructure of films in agreement with SEM imagines. Experimental results indicated that morphology, microstructure and luminescence of Au/SiO2 nanocomposite films showed close affinity with annealing temperature and annealing time.

Performance improvement of amorphous indium-gallium-zinc oxide ReRAM with SiO2 inserting layer

Yanli Pei,Biaoren Mai,Xiaoke Zhang,Ruiqin Hu,Ya Li,Zimin Chen,Bingfeng Fan,Jun Liang,Gang Wang 한국물리학회 2015 Current Applied Physics Vol.15 No.4

In this study, the resistive switching performance of amorphous indiumegalliumezinc oxide (a-IGZO) resistive switching random-access memory (ReRAM) was improved by inserting a thin silicon oxide layer between silver (Ag) top electrode and a-IGZO resistive switching layer. Compared with the single a-IGZO layer structure, the SiO2/a-IGZO bi-layer structure exhibits the higher On/Off resistance ratio larger than 103, and the lower operation power using a smaller SET compliance current. In addition, good endurance and excellent retention characteristics were achieved. Furthermore, multilevel resistance states are obtained through adjusting SET compliance current and RESET stop voltage, which shows a promise for high-performance nonvolatile multilevel memory application.