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Formation of a disordered region at the grain boundary during migration with He atoms

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Science China(Physics,Mechanics & Astronomy) 2017年第4期60卷 78-81页

作者： shi Yuan Hu Yi Yu wei shi Yuan YuHan Wang XiaoLin Shu GuangHong Lu Department of Physics Beihang University Institute of Applied Physics & Computational Mathematics Software Center for High Performance Numerical Simulation

W is considered a potential candidate as a plasma facing ma- terial for future nuclear fusion devices because of its high melting point, low sputtering rate, and low H or He solubility [1-3]. In a fusion environment, W will be in direct contact with heat flux, H/He particle fluxes, and the irradiation of high-energy neutrons, causing several defects to be generated, which decrease the service life of W materials. The grain boundary （GB）, which is an important type of defect, affects the various physical and mechanical properties of ma- terials. In the nuclear environment, the GB can act as a sink for the defects when the material is under irradiation.

关键词： migration sputtering solubility irradiation melting disordered defects candidate facing causing

Intratumour microbiome of pancreatic cancer

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World Journal of Gastrointestinal Oncology 2023年第5期15卷 713-730页

作者： shi-wei Guan Quan Lin Hai-Bo Yu Department of Surgery Wenzhou Central HospitalThe Dingli Clinical Institute of Wenzhou Medical UniversityWenzhou 325000Zhejiang ProvinceChina

Pancreatic cancer is a high mortality malignancy with almost equal mortality and morbidity *** normal and tumour tissues of the pancreas were previously considered *** recent years,with the development of technologies for highthroughput sequencing,a variety of studies have revealed that pancreatic cancer tissues contain small amounts of bacteria and *** intratumour microbiome is being revealed as an influential contributor to *** intratumour microbiome has been identified as a crucial factor for pancreatic cancer progression,diagnosis,and treatment,chemotherapy resistance,and immune response.A better understanding of the biology of the intratumour microbiome of pancreatic cancer contributes to the establishment of better early cancer screening and treatment *** review focuses on the possible origins of the intratumour microbiome in pancreatic cancer,the intratumour localization,the interaction with the tumour microenvironment,and strategies for improving the outcome of pancreatic cancer ***,this review offers new perspectives for improving the prognosis of pancreatic cancer.

关键词： Intratumour microbiome Pancreatic cancer Tumour microenvironment Chemoresistance Diagnosis Prognosis

Blow-Up Solution of the 3D Viscous Incompressible MHD System

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Journal of Partial Differential Equations 2020年第2期33卷 109-118页

作者： YANG Xin-Guang shi wei LU Yongjin Department of Mathematics and Information Science Henan Normal UniversityXinxiang 453007China Department of Mathematics and Economics Virginia State UniversityPetersburgVA 23806USA

The 3D viscous incompressible magneto-hydrodynamic (MHD) system comprised by the 3D incompressible viscous Navier-Stokes equation couples with Maxwell *** global well-posedness of the coupled system is still an open *** this paper,we study the Cauchy problem of this coupled system and establish some logarithmical type of blow-up criterion for smooth solution in Lorentz spaces.

关键词： MHD equations blow-up criteria Lorentz space

Preparation of Porous Silica Ceramics with Low Dielectric Constant

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Chinese Journal of Aeronautics 2006年第B12期19卷 239-243页

作者： MAO Xiao-jian WANG shi-wei shiMAI Shun-zo Shanghai Institute of Ceramics Chinese Academy of Science Shanghai 200050 China Graduate School of Chinese Academy of Science Beijing 100039 China

Porous silica ceramics has been prepared with the starch consolidation casting method. Slurries with various fractions of starch added in were prepared by ball-milling. The evaluation of the microstructures was done through two techniques： Hg porosimetry and SEM investigation. The bending strength of the sintered samples varied within the range of 10 MPa-20 MPa and the low dielectric constant within the range of 2.0-2.4 correspondent with the porosity of 42%-56%. The ceramics holds a brilliant promise of being a kind of core material used in sandwich-like electromagnetic windows.

关键词： porous ceramics SiO2 starch consolidation casting bending strength dielectric properties

Long duplication of 18S ribosomal DNA in Cynoglossus lineolatus(Pleuronectiformes： Cynoglossidae)： novel molecular evidencefor unequal crossing over model

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Acta Oceanologica Sinica 2016年第12期35卷 38-50页

作者： GONG Li shi wei YANG Min SI Lizhen KONG Xiaoyu Guangxi Key Laboratory of Mangrove Conservation and Utilization Guangxi Mangrove Research Center Guangxi Academy of Sciences Beihai 536000 China Key Laboratory of Tropical Marine Bio-resources and Ecology/Guangdong Provincial Key Laboratory of Applied Marine Biology South China Sea Institute of Oceanology Chinese Academy of Sciences Guangzhou 510000 China University of the Chinese Academy of Sciences Beijing 100049 China

Although 18 S r DNA sequence is extremely conservative, the polymorphism still has been found in few *** the present study, three types(Type A, B and C) of 18 S r DNA sequence coexisted in Cynoglossus lineolatus genome, suggesting a non-concerted evolution process, rather than a strictly concerted evolution *** on the differences of sequence variation, GC content, secondary structure and minimum free energy,Types A and B were speculated as the potential pseudogenes. Additionally, a fascinating finding was a 189-bp duplication of 18 S r DNA in Type A sequence. To our knowledge, this is the first report on such a long duplication in teleostean ribosomal DNA. Compared with several theories accounting for the formation of tandem repeats, the unequal crossing over model was thought to be the most likely mechanism to generate the189-bp duplication of 18 S r DNA. These results not only provide a novel molecular evidence for the unequal crossing over model, but also benefit for the further study on 18 S r DNA in fishes.

关键词： nrDNA Cynoglossus lineolatus tandem repeat pseudogene polymorphism non-concerted evolution

Spatial and Temporal Variability of Thermal Stress to China's Coral Reefs in South China Sea

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Chinese Geographical Science 2015年第2期25卷 159-173页

作者： ZUO Xiuling SU Fenzhen WU Wenzhou CHEN Zhike shi wei State Key Laboratory of Resources and Environmental Information System Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences University of Chinese Academy of Sciences Heilongjiang Agricultural Reclamation Survey Design and Research Institute

Coral bleaching, caused by elevated sea surface temperature(SST), is occurring more frequently and seriously worldwide. Due to the lack of field observations, we understand little about the large-scale variability of thermal stress in the South China Sea(SCS) and its effect on China's coral reefs. This paper used 4-km high resolution gap-filled SST(Filled SST) data and thermal stress data related to coral bleaching derived from Coral Reef Temperature Anomaly Database(Co RTAD) to quantify the spatial and temporal characteristics of chronic thermal stress and acute thermal stress to China's coral reefs in SCS from 1982 to 2009. We analyzed the trend of SST in summer and the thermal stress frequency, intensity and duration during this period. The results indicate that, as a chronic thermal stress, summer mean SST in SCS shows an average upward trend of 0.2℃/decade and the spatial pattern is heterogeneous. Waters of Xisha Islands and Dongsha Islands of the northern SCS are warming faster through time compared to Zhongsha Islands and Nansha Islands sea areas of the southern SCS. High frequency bleaching related thermal stress events for these reefs are seen in the area to the northwest of Luzon Island. Severe anomaly thermal stress events are more likely to occur during the subsequent year of the El Nino year for these coral reefs. Besides, the duration of thermal stress varies considerably by anomaly year and by region.

关键词： coral reef sea surface temperature(SST) thermal stress El Nino-Southern Oscillation(ENSO) South China Sea(SCS)

Tripartition of Arbitrary Single-Qubit Information via a Class of Asymmetric Four-Qubit W State

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Communications in Theoretical Physics 2009年第10期52卷 606-610页

作者： YIN Xiao-Feng LIU Yi-Min shi shi-wei ZHANG Wen ZHANG Zhan-Jun School of Physics ＆ Material Science Anhui University Hefei 230039 China Department of Physics Shaoguan University Shaoguan 512005 China Key Laboratory of Optoelectronic Information Acquisition ＆ Manipulation of Ministry of Education School of Physics Material Science Anhui University Hefei 230039 China

A four-party scheme is put forward for a sender to partition arbitrary single-qubit information among three receivers by utilizing a class of asymmetric four-qubit W state as quantum channels. In the scheme the sender＇s quantum information can be recovered by the three receivers if and only if they collaborate together. Specifically, they collaborate to perform first two different 2-qubit collective unitary operations and then a single-qubit unitary operation. The scheme is symmetric and （3, 3）-threshold with regard to the reconstruction, for any receiver can be assigned to conclusively recover the quantum information with the other two＇s assistances.

关键词： four-party scheme tripartition arbitrary single-qubit quantum information asymmetric fourqubit W state

A Localization Algorithm Using a Mobile Anchor Node Based on Region Determination in Underwater Wireless Sensor Networks

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Journal of Ocean University of China 2019年第2期18卷 394-402页

作者： XU Tingting WANG Jingjing shi wei WANG Jianfeng CHEN Zhe School of Information Science and Technology Qingdao University of Science and Technology

At present, most underwater positioning algorithms improve the positioning accuracy by increasing the number of anchor nodes which resulting in the increasing energy consumption. To solve this problem, the paper proposes a localization algorithm assisted by mobile anchor node and based on region determination(LMRD), which not only improves the positioning accuracy of nodes positioning but also reduces the energy consumption. This algorithm is divided into two stages: region determination stage and location positioning stage. In the region determination stage, the target region is divided into several sub-regions by the region division strategy with the smallest overlap rate which can reduce the number of virtual anchor nodes and lock the target node to a sub-region, and then through the planning of mobile nodes to optimize the travel path, reduce the moving distance, and reduce system energy consumption. In the location positioning stage, the target node location can be calculated using the HILBERT path planning and trilateration. The simulation results show that the proposed algorithm can improve the positioning accuracy when the energy consumption is reduced.

关键词： UWSN mobile anchor nodes energy consumption region determination localization algorithm

Variation of soil-plant-atmosphere continuum stable isotope and water source in Qinghai spruce forest of the eastern Qilian Mountains

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Journal of Mountain Science 2023年第2期20卷 355-366页

作者： ZHOU Jun-ju WANG Xue MA Luo LUO Chu-yu TANG Hai-tao GUO Zhao-nan CHEN Jia-wei shi Su-han shi wei wei wei ZHANG Dong-xia LIU Chun-fang College of Geography and Environmental Science Northwest Normal UniversityLanzhou 730070China Key Laboratory of Resource Environment and Sustainable Development of Oasis Lanzhou 730070China Sate Key Laboratory of Earth Surface Processes and Resource Ecology Faculty of Geographical ScienceBeijing Normal UniversityBeijing 100875China

Understanding the hydrogen and oxygen stable isotope composition and characteristics of different water bodies in soil-plant-atmosphere continuum is of significance for revealing regional hydrological processes and water cycle *** this study,we analyzed the stable isotopic composition,relationship and indicative significance of precipitation,soil water(0~100 cm depth)and xylem water of Qinghai spruce(Picea crassifolia)forest in the eastern Qilian Mountains,and explored the circulation process among different water *** results show that the stable isotopes of precipitation vary greatly during the entire observation *** values ofδ2H andδ^(18)O in the precipitation in the warm season are richer than those in the cold season,and the slope and intercept of local meteoric water line(LMWL,δ2H=6.79δ18O+7.13)are both smaller than global meteoric water line(GMWL,δ2H=8.17δ18O+10.56).The stable isotopes of soil water at different depths underwent different degrees of evaporative fractionation,and theδ18O andδ2H of shallow soil water varied greatly,while the deep soil water tended to be *** topsoil(0~10 cm)can respond quickly to precipitation,and the response of the deep soil has a time *** the whole growing season,0~30 cm and 60~100 cm soil water are the main water sources of Qinghai *** water source of Qinghai spruce was from all soil layers in May and September,mainly from the shallow soil layer(0~30 cm)in August and October,and mainly from the deep soil layer(60~100 cm)in June and July.

关键词： Stable hydrogen isotope Stable oxygen isotope Soil-plant-atmosphere continuum SPAC Plant water use IsoSource model