Involvement of DNA-dependent Protein Kinase in UV-induced Replication Arrest

Park, Jang-Su,Park, Su-Jung,Peng, Xiaodong,Wang, Mu,Yu, Myeing-Ae,Lee, Suk-Hee 부산대학교 유전공학연구소 1999 분자생물학 연구보 Vol.15 No.-

Cells exposed to UV irradiation are predominantly arrested at S-phase as well as at the G_1/S boundary while repair occurs. It is not known how UV irradiation induces S-phase arrest and yet permits DNA repair, however, UV-induced inhibition of replication is efficiently reversed by the addition of replication protein A (RPA) suggesting a role for RPA in this regulatory event. Here, we show evidence that DNA-dependent protein kinase (DNA-PK), plays a role in UV-induced replication arrest. DNA synthesis of M059K(DNA-PK catalytic subunit-positive (DNS-PKcs^+)), as measured by [^3H]thymidine incorporation, was significantly arrested by 4 h following UV irradiation, whereas M059J (DNA-PK^-) cells were much less affected. Similar results were obtained with the in vitro replication reactions where immediate replication arrest occurred in DNA-PKcs^+ cells following UV irradiation, and only a gradual decrease in replication activity was observed in DNA-PKcs^- cells. Reversal of replication arrest was observed at 8 h following UV cells. Reversal of UV-induced replication arrest was also observed in vitro by the addition of a DNA-PK inhibitor, wortmannin, or by immunodepletion of DNA-PKcs, supporting a positive role for DNA-PK in damage-induced replication arrest. The RPA-containing fraction from UV-irradiated DNA-PKcs^+ cells poorly supported DNA replication, whereas the replication activity of the RPA-containing fraction from DNA-PKcs^- cells was not affected by UV, suggesting that DNA-PKcs may be involved in UV-induced replication arrest through modulation of RPA activity. Together, our results strongly suggest a role for DNA-PK in S-phase (replication) arrest in response to UV irradiation.

Stamping Manipulator Trajectory Planning Based On Virtual Prototype Technology Research

Su Chunjian,Yan Nannan,Lou Shumei,Zhang Xiaodong,Lu Shun,Wang Qing 보안공학연구지원센터 2016 International Journal of Signal Processing, Image Vol.9 No.4

In view of the problem that the joint type multiple DOF Manipulator is easy to collide with the surrounding equipment and jitter caused by the joint movement, this paper based on the stamping manipulator of five DOF cylindrical coordinate type, planned a straight path through actual stamping process in Cartesian space and quadratic programmed by using a bounded deviation theory. Then, this paper respectively used cubic polynomial, five polynomial and B-spline interpolation on interpolation points in joint space, and analyzed the displacement, velocity and acceleration of the end reference point. Finally, model in virtual prototype and real experiments were verified to ensure the safety and precision of the path. The results meet the requirements of the stamping process, succeeded in raising the stamping accuracy, and ensured the quality of stamping, and can arrange the entire auto production line equipment. So, it has important theoretical and practical significance to improve the stamping process.

PERSONALIZED STEERING FEEL DESIGN FOR STEER-BY-WIRE SYSTEMS BASED ON THE RACK FORCE ESTIMATION

Su Chengrui,Li Huanghe,Qiao Bangjun,Wu Xiaodong 한국자동차공학회 2023 International journal of automotive technology Vol.24 No.4

This paper proposes a personalized steering feel model for the steer-by-wire vehicles to reconstruct the haptic feedback during steering motion. Through the investigation of the steering mechanism, the aligning torque obtained via the rack force estimated by the extended disturbance observer and the equivalent friction torque modelled using a hyperbolic tangent function constitute the steering feel model. Also, different mathematical functions are designed to achieve the characteristics of the power assist and the steering feel varying with vehicle speeds. The variable parameters are introduced to design the personalized steering feel and the objective evaluation is employed to evaluate the performance of the proposed model. The hardware-in-the-loop experiment results demonstrate that the designed extended disturbance observer has good rack force estimation performance. Compared with conventional electric power steering systems, the proposed model achieves the same haptic feedback and has the assist effect and the characteristics of steering feel that changes with speed. Furthermore, the personalized steering feel is realized by adjusting the variable parameters of the steering feel model according to different drivers’ preferences.

Antibacterial and anti-mildew behavior of chitosan/nano-TiO2 composite emulsion

Haijia Su,Lei Shi,Yan Zhao,Tianwei Tan,Xiaodong Zhang 한국화학공학회 2008 Korean Journal of Chemical Engineering Vol.25 No.6

A novel chitosan/nano-TiO2 composite emulsion (CTCE) was prepared by inverse suspension technology, and its multi-function properties were studied. As can be seen from the results, the gauze treated with chitosan/ nano-TiO2 composite emulsion showed excellent antibacterial activities against Escherichia coli, Aspergillus niger and Candida albicans that the bactericidal ratios could reach 99.96%, 100% and 78.3% after 24 h, respectively. At the same time, the chitosan/nano-TiO2 composite emulsion could really kill the bacteria, not just inhibit its growth, and the bactericidal ratio for E. coli could reach 70.3% after 1 h. The bactericidal ratio for E. coli reached 98.8% at 27 oC compared with 58.7% at 18 oC after 8 h due to the activity of bacteria being weakened at low temperature. Furthermore, the antibacterial ability of antibacterial gauze was hardly influenced with the increase of storage time, which could be reused for up to 8 times without loss of antibacterial ability.

Development of a Targeted Recommendation Model for Earthquake Risk Prevention in the Whole Disaster Chain

( Xiaohui Su ),( Keyu Ming ),( Xiaodong Zhang ),( Junming Liu ),( Da Lei ) 한국정보처리학회 2021 Journal of information processing systems Vol.17 No.1

Strong earthquakes have caused substantial losses in recent years, and earthquake risk prevention has aroused a significant amount of attention. Earthquake risk prevention products can help improve the self and mutualrescue abilities of people, and can create convenient conditions for earthquake relief and reconstruction work. At present, it is difficult for earthquake risk prevention information systems to meet the information requirements of multiple scenarios, as they are highly specialized. Aiming at mitigating this shortcoming, this study investigates and analyzes four user roles (government users, public users, social force users, insurance market users), and summarizes their requirements for earthquake risk prevention products in the whole disaster chain, which comprises three scenarios (pre-quake preparedness, in-quake warning, and post-quake relief). A targeted recommendation rule base is then constructed based on the case analysis method. Considering the user’s location, the earthquake magnitude, and the time that has passed since the earthquake occurred, a targeted recommendation model is built. Finally, an Android APP is implemented to realize the developed model. The APP can recommend multi-form earthquake risk prevention products to users according to their requirements under the three scenarios. Taking the 2019 Lushan earthquake as an example, the APP exhibits that the model can transfer real-time information to everyone to reduce the damage caused by an earthquake.

Design and Implementation of Soil Nutrient Monitoring System Based on “3S” Technology

Di Zu,Zhongbin Su,Xiaodong Yang,Xiaohe Gu,Yancang Wang 보안공학연구지원센터 2015 International Journal of Smart Home Vol.9 No.5

Soil nutrient monitoring system is to master the nutrient status of the bare ground, and quickly extract the information of farmland nutrient. Because of having a significant impact on the crop, the soil nutrient monitoring is important. For the lack of monitoring soil nutrient monitoring currently, combined with “3S” technology, spatial database technology, computer network technology and modern agricultural information technology as the basis, using WebGIS Service standard spatial database engine, the soil nutrient monitoring system based on soil nutrient information of Yangling was scientifically constructed. It achieved soil nutrient management from the large-scale, made the monitoring process towards standardization, improved management efficiency and scientific level, and provided technical support for farmland quality decisions.

Parking Lot Optimal Routing Based on Grey Entropy Relation Grade Multi-Attribute Decision Making

Zhang Yuru,Zhao Wuchen,Li Hui,Su Xiaodong,Zhao Ming 보안공학연구지원센터 2015 International Journal of Smart Home Vol.9 No.2

A zeolite family with expanding structural complexity and embedded isoreticular structures

Guo, Peng,Shin, Jiho,Greenaway, Alex G.,Min, Jung Gi,Su, Jie,Choi, Hyun June,Liu, Leifeng,Cox, Paul A.,Hong, Suk Bong,Wright, Paul A.,Zou, Xiaodong Nature Publishing Group, a division of Macmillan P 2015 Nature Vol.524 No.7563

The prediction and synthesis of new crystal structures enable the targeted preparation of materials with desired properties. Among porous solids, this has been achieved for metal–organic frameworks, but not for the more widely applicable zeolites, where new materials are usually discovered using exploratory synthesis. Although millions of hypothetical zeolite structures have been proposed, not enough is known about their synthesis mechanism to allow any given structure to be prepared. Here we present an approach that combines structure solution with structure prediction, and inspires the targeted synthesis of new super-complex zeolites. We used electron diffraction to identify a family of related structures and to discover the structural ‘coding’ within them. This allowed us to determine the complex, and previously unknown, structure of zeolite ZSM-25 (ref. 8), which has the largest unit-cell volume of all known zeolites (91,554 cubic ångströms) and demonstrates selective CO<SUB>2</SUB> adsorption. By extending our method, we were able to predict other members of a family of increasingly complex, but structurally related, zeolites and to synthesize two more-complex zeolites in the family, PST-20 and PST-25, with much larger cell volumes (166,988 and 275,178 cubic ångströms, respectively) and similar selective adsorption properties. Members of this family have the same symmetry, but an expanding unit cell, and are related by hitherto unrecognized structural principles; we call these family members embedded isoreticular zeolite structures.