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Journal of Mountain Science 2018年第5期15卷 1115-1128页

作者： DONG chun-liang ZHAO Guang-ming LU xiao-yu MENG Xiang-rui LI ying-ming CHENG Xiang Key Laboratory of Safety and High-efficiency Coal Mining Ministry of Education Anhui University of Science and Technology School of Mechanics and Photoelectric Physics Anhui University of science and Technology School of Mining and Safety Anhui University of Science and Technology

The unloading effect of the excavation of deep roadways has been considerably studied, but most research methods have been limited to numerical simulations and field measurements. Only a few have adopted experimental methods for similar simulations. On the basis of the theory of mechanics,the testing system is designed considering initial geostress and dynamic unloading. The system includes an impact unloading gear and in-situ stress loading equipment, and a designed three-link structure and the impact hammer can effectively realize the dynamic excavation of ***, a cyclic excavation similar simulation experiment on a deep roadway is conducted in a laboratory. The testing system and the relevant monitoring facilities are utilized, and the unloading effect inside the surrounding rock under the cyclic dynamic excavation is studied. Results show that the cyclic dynamic excavation causes significant unloading only in the nearby rock mass, and the unloading indicators show nonlinear ***, when the lateral pressure coefficient is 1.2,the damage is concentrated on both roadsides due to the excavation unloading. Meanwhile, the damage gradually decays as the span increases.

关键词： Excavation unloading in deep roadways Unloading effect Damage of surrounding rock Circular excavation Unloading index

FPGA-based edge computing: Task modeling for cloud-edge collaboration

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International Journal of Modeling, Simulation, and Scientific Computing 2022年第2期13卷 148-167页

作者： Chuan xiao chun Zhao School of Computer Beijing Information Science and Technology University Beijing 100101 China

With the development of the Internet of Things and devices continuing to scale,using cloud computing resources to process data in real-time is *** computing technologies can improve real-time performance in processing *** introducing the FPGA into the computing node and using the dynamic reconfigurability of the FPGA,the FPGA-based edge node can increase the edge node *** this paper,a task-based collaborative method for an FPGA-based edge computing system is proposed in order to meet the collaboration among FPGA-based edge nodes,edge nodes,and the *** modeling of the task includes two parts,task information and task-dependent *** information is used to describe the running information and dependency infor-mation required for the task ***-dependent file contains the configuration bit-stream of FPGA in running of the *** analyzing the task behavior,this paper builds four basic behaviors,analyzes the critical attributes of each behavior,and summa-rizes the task model suitable for FPGA-based edge *** with specific functions can be created by modifying different attributes of model ***,the availability of the model and the task-based collaborative method are verified by simulation *** experimental results that the task model proposed in this paper can meet cloud-edge collaboration in the FPGA-based edge computing environment.

关键词： Task modeling edge computing cloud-edge collaboration

Finite Thrust Transfer Strategy Designing for Low Energy Moon Return Based on GPM/VSM

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International Journal of Automation and computing 2015年第5期12卷 490-496页

作者： Liu Yue Wu-Xing Jing ying-ying xiao Department of Astronautics Engineering Harbin Institute of Technology

In a low energy moon return mission, due to the weak stability of the orbit, it is necessary to implement an accurate orbital maneuver to guarantee a successful return. During the process of getting the optimal thrust control with these two kinds of methods, it is hard to guess the initial value of the co-states in the indirect method while a large amount of calculation is needed to insure the precision in the direct method. To solve the problem, in this paper a combined method is given which has the merit of both direct and indirect methods. In this method, the virtual satellite method(VSM) and the Gauss pseudo-spectral method(GPM)are applied, while the fuel optimal control strategy is computed with GPM to carry out a soft rendezvous between the spacecraft and a hypothetical virtual satellite running on the nominal low energy return orbit so that the spacecraft will enter the return orbit accurately. Compared with the direct and indirect methods, this combined method can avoid guessing the initial value of the co-states and the complexity of calculation is acceptable. According to the simulation results, the spacecraft is inserted to the target return orbit with a high accuracy and also the optimization is very effective.

关键词： Moon trajectories optimization and simulation virt

Synthesis and Cytotoxic Activity of Novel Water-soluble Prodrugs of Combretastatin A-4

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Chinese Chemical Letters 2006年第1期17卷 23-26页

作者： Zhi Quart YONG xiao Ping XU ying chun CHEN Xu BAO Ling Ling WENG Hu ZHENG Department of Medicinal Chemistry West China School of Pharmacy Sichuan University Chengdu 610041

Novel water-soluble prodrugs of combretastatin A-4 （5-8） were synthesized and evaluated for their in vitro cytotoxicity against lung carcinoma A549. Compound 5, bearing phosphoryl choline （PC） moiety, showed 90% inhibition at 32 ktg/mL concentration after 24 h. The findings showed the PC derivative would be a promising candidate for the development of new water-soluble prodrug of cytotoxic combretastatin A-4,

关键词： Combretastafin A-4 cytotoxicity phosphoryl choline water-soluble prodrug.

Expression Pattern Analysis of Zinc Finger Protein Genes in Wheat(Triticum aestivum L.) Under Phosphorus Deprivation

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Journal of Integrative Agriculture 2014年第8期13卷 1621-1633页

作者： LI xiao-juan GUO Cheng-jin LU Wen-jing DUAN Wei-wei ZHAO Miao MA chun-ying GU Jun-tao xiao Kai College of Life Sciences Agricultural University of Hebei College of Agronomy Agricultural University of Hebei Science & Technology College North China Electric Power University

Zinc finger protein（ZFP） genes comprise a large and diverse gene family, and are involved in biotic and abiotic stress responses in plants. In this study, a total of 126 ZFP genes classified into various types in wheat were characterized and subjected to expression pattern analysis under inorganic phosphate（Pi） deprivation. The wheat ZFP genes and their corresponding GenBank numbers were obtained from the information of a 4×44K wheat gene expression microarray chip. They were confirmed by sequence similarity analysis and named based on their homologs in Brachypodium distachyon or Oriza sativa. Expression analysis based on the microarray chip revealed that these ZFP genes are categorized into 11 classes according to their gene expression patterns in a 24-h of Pi deprivation regime. Among them, ten genes were differentially up-regulated, ten genes differentially downregulated, and two genes both differentially up- and down-regulated by Pi deprivation. The differentially up- or down-regulated genes exhibited significantly more or less transcripts at one, two, or all of the checking time points（1, 6, and 24 h） of Pi stress in comparison with those of normal growth, respectively. The both differentially up- and down-regulated genes exhibited contrasting expression patterns, of these, TaWRKY70;5 showed significantly up-regulated at 1 and 6 h and down-regulated at 24 h whereas TaAN1AN20-8;2 displayed significantly upregulated at 1 h and downregulated at 6 h under deprivation Pi condition. Real time PCR analysis confirmed the expression patterns of the differentially expressed genes obtained by the microarray chip. Our results indicate that numerous ZFP genes in wheat respond to Pi deprivation and have provided further insight into the molecular basis that plants respond to Pi deprivation mediated by the ZFP gene family.

关键词： wheat(Triticum aestivum L.) zinc finger protein Pi deprivation gene expression

Antibiotic exposure perturbs the bacterial community in the small brown planthopper Laodelphax striatellus

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Insect Science 2020年第5期27卷 895-907页

作者： Xu Zhang Tong-Pu Li chun-ying Zhou Dian-Shu Zhao Yu-Xi Zhu xiao-Li Bing Hai-Jian Huang xiao-Yue Hong Department of Entomology Nanjing Agricultural UniversityNanjingChina

Bacteria symbionts in herbivores play an important role in host biology and ecology,and are affected by environmental factors such as temperature,diet,habitat,antibiotics and so ***,the effects of antibiotics on the microbiome of the small brown planthopper Laodelphax striatellus(SBPH)remain ***,we studied the effects of tetracycline on the diversity and composition of bacterial colonies in different tissues of SBPH using high throughput sequencing of 16S ribosomal RNA *** results show that Proteobacteria,Firmicutes,Bacteroidetes,Actinobacteria were most abundant in SBPH,and the genera Asaia and Wolbachia were most abundant in all body parts of *** treatment had persistent effects on the composition of the SBPH *** depleted the population of Firmicutes,Bacteroidetes,Tenericutes and Fusobacteria,and nearly 100%eliminated Wolbachia,Bacteroides and Abiotrophia in ***,these results suggest that antibiotic exposure affects the bacteria symbionts of different body parts in SBPH and will facilitate future studies of the bacterial symbionts of arthropod hosts.

关键词： antibiotics gut Laodelphax striatellus microbial structure ovary

Effects of lanthanum(Ⅲ) on nitrogen metabolism of soybean seedlings under elevated UV-B radiation

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Journal of Environmental Sciences 2007年第11期19卷 1361-1366页

作者： CAO Rui HUANG xiao-hua ZHOU Qing CHENG xiao-ying The Key Laboratory of Industrial Biotechnology Ministry of Education Southern Yangtze University Wuxi 214036 China College of Chemistry and Environment Science Nanjing Normal University Nanjing 210097 China

The hydroponic culture experiments of soybean bean seedlings were conducted to investigate the effect of lanthanum （La） on nitrogen metabolism under two different levels of elevated UV-B radiation （UV-B, 280-320 nm）. The whole process of nitrogen metabolism involves uptake and transport of nitrate, nitrate assimilation, ammonium assimilation, amino acid biosynthesis, and protein synthesis. Compared with the control, UV-B radiation with the intensity of low level 0.15 W/m^2 and high level 0.45 W/m^2 significantly affected the whole nitrogen metabolism in soybean seedlings （p 〈 0.05）. It restricted uptake and transport of NO3^-, inhibited activity of some key nitrogen-metabolism-related enzymes, such as： nitrate reductase （NR） to the nitrate reduction, glutamine systhetase （GS） and glutamine synthase （GOGAT） to the ammonia assimilation, while it increased the content of free amino acids and decreased that of soluble protein as well. The damage effect of high level of UV-B radiation on nitrogen metabolism was greater than that of low level. And UV-B radiation promoted the activity of the anti-adversity enzyme glutamate dehydrogenase （GDH）, which reduced the toxicity of excess ammonia in plant. After pretreatment with the optimum concentration of La （20 mg/L）, La could increase the activity of NR, GS, GOGAT, and GDH, and ammonia assimilation, but decrease nitrate and ammonia accumulation. In conclusion, La could relieve the damage effect of UV-B radiation on plant by regulating nitrogen metabolism process, and its alleviating effect under low level was better than that under the high one.

关键词： lanthanum(Ⅲ) UV-B radiation soybean seedlings nitrogen metabolism alleviating effect

Protective effects of pentadecapeptide BPC 157 on gastric ulcer in rats

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World Journal of Gastroenterology 2004年第7期10卷 1032-1036页

作者： xiao-ChangXue Yong-JieWu Ming-TangGao Wen-GuangLi NingZhao Zeng-LuWang chun-JieBao ZhenYan ying-QiZhang BiotechnologyCentre FourthMilitaryMedicalUniversityXi'an710032ShaanxiProvinceChina DepartmentofPharmacology LanzhouMedicalCollegeLanzhou730000GansuProvinceChina BiotechnologyCentre FourthMilitaryMedicalUniversityXi'an710032ShaanxiProvinceChina

AIM: To investigate the protective effects of gastric pentadecapeptide BPC 157 on acute and chronic gastric ulcers in rats and to compare the results in therapy of human gastric ulcers by different administration methods. METHODS: Gastric pentadecapeptide BPC 157 was administered (initial single or continuous administration) into rats either intragastrically or intramuscularly before (induced acute gastric ulcer) or after (induced chronic gastric ulcer) the applications of inducing agents, and each animal was sacrificed to observe the protective effects of BPC 157 on gastric ulcers. RESULTS: Both intramuscular (im) and intragastric (ig) administration of BPC 157 could apparently reduce the ulcer area and accelerate the healing of induced ulcer in different models and the effect of im administered BPC 157 was better than that of ig. The rats treated with higher dosages (400 ng/kg, 800 ng/kg) of BPC 157 (im and ig) showed significantly less lesion (P<0.01 vs excipient or saline control), the inhibition ratio of ulcer formation varied between 45.7% and 65.6%, from all measurements except 400 ng/kg BPC 157 in pylorus ligation induced model (P<0.05), in which the inhibition rate was 54.2%. When im administered (800 ng/kg BPC 157) in three modeis, the inhibition ratio of ulcer formation was 65.5%, 65.6% and 59.9%, respectively, which was better than that of famotidine (its inhibition rate was 60.8%, 57.2% and 34.3%, respectively). Continuous application of BPC 157 (in chronic acetate induced gastric ulcer) could accelerate rebuilding of glandular epithelium and formation of granulation tissue (P<0.05 at 200 ng/kg and P<0.01 at 400 ng/kg and 800 ng/kg vs excipient or saline control). CONCLUSION: Both im and ig administered gastric pentadecapeptide BPC 157 can apparently ameliorate acute gastric ulcer in rats and antagonize the protracted effect of acetate challenge on chronic ulcer. The effect of im administration of BPC 157 is better than that of ig, and the effective dos

关键词：胃溃疡十五肽BPC157 动物实验作用机制胃粘膜

High thermoelectric properties of Cu_(2)TeeAg_(2)Te composite with Fe addition and non-stoichiometric Te

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Journal of Materiomics 2024年第1期10卷 37-44页

作者： Wenxiu Li Su Dun Bin xiao Jun Wang Xinba Yaer chun ying Ye Li xiaohuan Wang Huijun Kang School of Materials Science and Engineering Inner Mongolia University of TechnologyHohhot010051China Research and Development Center HUA Cloud Intelligent Healthcare Co.LtdShenzhen518000China College of Sciences Inner Mongolia University of TechnologyHohhot010051China Key Laboratory of Solidification Control and Digital Preparation Technology(Liaoning Province) School of Materials Science and EngineeringDalian University of TechnologyDalian116024China

Cu_(2)Te-based materials are a type of superionic conductor belonging to the class of phonon-liquid elec-tron-crystal materials and have achieved high ZT values by doping and ***,it is easy to form copper vacancies in Cu_(2)Te which leads to an excessive carrier concentration and then results in a low Seebeck ***,controlling copper ion migration and optimizing carrier concen-tration is essential to improve the thermoelectric performance of Cu_(2)*** paper reports high-performance Cu_(2)TeeAg_(2)Te composite with high application value in the low-middle temperature re-gion,which is achieved by fine tuning the carrier concentration using Fe addition and non-stoichiometric Te,as well as controlling the thermal conductivity of composite.A high ZT of~1.2 is obtained in AgCu_(0.97)Fe_(0.03)Te_(0.96)at a low temperature of 573 ***,the phase transition mechanism of Cu_(2)TeeAg_(2)Te and its effect on the thermoelectric transport performance are revealed that go beyond nanostructuring and single-doping,which provides a strong theoretical basis for research and perfor-mance improvement of thermoelectric materials in this system.

关键词： Thermoelectric AgCuTe Fe addition Non-stoichiometric Te