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Advances in BeiDou Navigation Satellite System(BDS)and satellite navigation augmentation technologies

Satellite Navigation 2020年第1期1卷 126-148页

作者： Rui Li Shuaiyong Zheng Ershen Wang Jinping chen Shaojun feng Dun Wang Liwen Dai School of Electronic and Information Engineering Beihang UniversityNo.37 Xueyuan RoadHaidian DistrictBeijingChina Suzhou Institute Beihang UniversitySuzhou 215200China College of Electronic and Information Engineering Shenyang Aerospace UniversityNo.37 Daoyi South StreetDaoyi DistrictShenyangChina Beijing Satellite Navigation Center No.22 Beiqing RoadHaidian DistrictBeijingChina Qianxun Spatial Intelligence Inc. C5 BuildingNo.1688-38 North Guoquan RoadYangpu DistrictShanghaiChina Space Star Technology Co. Ltd.Blue Lake Industry ParkHaidian DistrictBei-jingChina John Deere-Intelligent Solution Group 20780 Madrona AvenueTorranceCAUSA

Several noteworthy breakthroughs have been made with the BeiDou Navigation Satellite System(BDS)and other global navigation satellite systems as well as the associated augmentation systems,such as the commissioning of the BDS-3 preliminary system and the successful launch of the first BDS-3 GEO satellite which carries the satellite-based augmentation ***,BDS can provide basic services globally,and its augmentation system is also being *** paper gives an overview of BDS and satellite navigation augmentation *** overview is divided into four parts,which include the system segment technologies,satellite segment technologies,propagation segment technologies,and user segment *** each part,these technologies are described from the perspectives of preliminary information,research progress,and ***,the significance and progress of the BeiDou Satellite-based Augmentation System(BDSBAS),low earth orbit augmentation,and the national BeiDou ground-based augmentation system are presented,along with the airborne-based augmentation ***,the conclusions and discussions covering popular topics for research,frontiers in research and development,achievements,and suggestions are listed for future research.

关键词： BeiDou Navigation Satellite System Satellite navigation augmentation systems System segment technologies Satellite segment technologies Propagation segment technologies User segment technologies

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A dimeric structure of PD-L1: functional units or evolutionary relics?

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Protein & Cell 2010年第2期1卷 153-160页

作者： Yong chen Peipei Liu feng Gao Hao cheng Jianxun Qi George F.Gao CAS Key Laboratory of Pathogenic Microbiology and Immunology Institute of MicrobiologyChinese Academy of Sciences(CASPMI)Beijing 100101China College of Life Sciences Graduate UniversityChinese Academy of SciencesBeijing 100049China Institute of Biophysics Chinese Academy of SciencesBeijing 100101China China-Japan Joint Laboratory of Molecular Immunology and Molecular Microbiology Institute of MicrobiologyChinese Academy of SciencesBeijing 100101China

PD-L1 is a member of the B7 protein family,most of whose members so far were identified as dimers in a solution and crystalline state,either complexed or uncomplexed with their ligand(s).The binding of PD-L1 with its receptor PD-1(CD279)delivers an inhibitory signal regulating the T cell *** with the Garboczi group,we successfully solved another structure of human PD-L1(hPD-L1).Our protein crystallized in the space group of C222_(1) with two hPD-L1 molecules per asymmetric *** comparison of reported B7 structures,we have found some intrinsic factors involved in the interaction of these two *** on these results,we tend to believe this uncomplexed hPD-L1 structure demonstrated its potential dimeric state in solution,althougt it could just be an evolutionary relic,too weak to be detected under present technology,or still a functional unit deserved our attentions.

关键词： PD-L1 crystal structure dimer costimulatory molecules B7 family

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Accuracy of a combined score of zygote and embryo morphology for selecting the best embryos for IVF

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2008年第8期9卷 649-655页

作者： Yu-li QIAN Ying-hui YE chen-ming XU Fan JIN He-feng HUANG Department of Reproductive Endocrinology Women＇s Hospital School of Medicine Zhejiang University Hangzhou 310006 China

Objective:To evaluate the accuracy of a scoring system combining zygote and embryo morphology in predicting the outcome of in vitro fertilization (IVF) treatment. Methods: In a study group, 117 consecutive IVF or intracytoplasmic sperm injection (ICSI) cycles with embryo transfer were carried out and 312 embryos were scored using a combined scoring system (CSS) of zygote and embryo morphology before transplantation. In a control group, a total of 420 IVF or ICSI cycles were carried out and 1176 embryos were scored using a cumulative embryo score (CES). The effects of the combined scoring system on the embryo implantation rate and pregnancy rate per cycle were analyzed. Results: Using the combined scoring system, the embryo implan-tation rate (27.6%) and the clinical pregnancy rate (48.7%) were significantly higher than those in the control group (20.8% and 38.6%, respectively). Also, the implantation rate of embryos scoring ≥70 (38.5%: 82 sacs/213 embryos) was significantly higher (P<0.001) than that of embryos scoring <70 (4%: 4 sacs/99 embryos). The pregnancy rate of patients with embryos scoring ≥70 using the combined scoring system (66.7%) was significantly higher (P<0.001) than that of patients with embryos scoring ≥20 using the cumulative embryo score (59.0%). Conclusion: The results suggest that selecting embryos with a high score (≥70) using the combined scoring system could increase the implantation rate and pregnancy rate, and that using a scoring system combining assessments of human zygotes and pre-implantation embryos might predict IVF outcomes more accurately than using a cumula-tive embryo score.

关键词： Embryo score Combined scoring system (CSS) Implantation In vitro fertilization (IVF) Pregnancy

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High-throughput volumetric reconstruction for 3D wheat plant architecture studies

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Journal of Innovative Optical Health Sciences 2016年第5期9卷 101-113页

作者： Wei Fang Hui feng Wanneng Yang Lingfeng Duan Guoxing chen Lizhong Xiong Qian Liu Britton Chance Center for Biomedical Photonics Wuhan National Laboratory for Optoelectronics Huazhong University of Science and Technology 1037 Luoyu Rd.Wuhan 430074 P.R.China National Key Laboratory of Crop Genetic Improvement and National Center of Plant Gene Research Huazhong Agricultural University Wuhan 430070 P.R.China College of Engineering Huazhong Agricultural University Wuhan 430070 P.R.China MOA Key Laboratory of Crop Ecophysiology and Farming System in the Middle Reaches of the Yangtze River Huazhong Agricultural University Wuhan 430070 P.R.China

For many tller crops,the plant archit ecture(PA),including the plant fresh weight,plant height,number of tllrs,tller angle and stem diameter,sigificantly afects the grain *** this study,we propose a method based on volumetric reconstruction for high-throughput three-dimensional(3D)wheat PA *** proposed methodology involves plant volumetric reconst ruction from multiple images,plant model processing and phenotypic parameter estimation and *** study was performed on 80 Triticum aestium plants,and the results were *** the automated measurements with manual measurements,the mean absolute per-centage error(MAPE)in the plant height and the plant fresh weight was 2.71%(1.08cm with an average plant height of 40.07cm)and 10.06%(1.41g with an average plant fresh weight of 14.06 g),*** root mean square error(RMSE)was 137 cm and 1.79g for the plant height and plant fresh weight,*** correlation cofficients were 0.95 and 0.96 for the plant height and plant fresh weight,***,the proposed methodology,in-cluding plant reconstruction,model processing and trait ext raction,required only approximately 20s on average per plant using parallel computing on a graphics processing unit(GPU),dem-onstrating that the methodology would be valuable for a high-throughput phenotyping platform.

关键词： Three-dimensional volumetric reconstruction plant architecture graphics processing unit high-throughput

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Preliminary analysis of the effect of vagus nerve stimulation in the treatment of children with intractable epilepsy

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World Journal of Clinical Cases 2020年第23期8卷 5918-5925页

作者： Tie Fang Zi-Hang Xie Ting-Hong Liu Jie Deng Shuai chen feng chen Li-Li Zheng Department of Functional Neurosurgery Beijing Children’s HospitalCapital Medical UniversityNational Center for Children’s HealthBeijing 100056China

BACKGROUND Implant vagus nerve stimulation is an adjunctive treatment for intractable epilepsy when patients are not suitable for resective *** To identify the safety and efficacy of vagus nerve stimulation in children with intractable epilepsy and analyze the effects on different epilepsy *** Eligible children with intractable epilepsy were admitted to the *** collected data from preoperative assessments as the *** the followup time,we recorded the process of seizures(frequency,duration,and seizure type),the changes of drugs or parameters,the complications,*** mean reduction rate of seizures,response rate,and McHugh scale were chosen as the *** A total of 213 patients were implanted with Tsinghua Pins vagus nerve stimulators,and the average age was 6.6 *** the follow-up time of postoperative 3 mo,6 mo,12 mo,18 mo,and 24 mo,the average reduction rate was 30.2%,49.5%,56.3%,59.4%,and 63.2%,while the response rate was 21.8%,62.5%,57.1%,69.2%,and 70.7%.In addition,implanted vagus nerve stimulation had different effects on epilepsy *** reduction rate of West syndrome increased from 36.4%(postoperative 6 m)to 74.3%(postoperative 24 m).The reduction rate of Lennox-Gastaut syndrome improved from 25.4%to 73.1%in 24 *** chi-square test of the five efficacy grades showed P*** Vagus nerve stimulation is safe and effective in children with intractable epilepsy,and the seizure reduction occurred in a time-dependent ***,patients with West syndrome may get the most benefits.

关键词： Vagus nerve Stimulation Children Intractable epilepsy Epilepsy syndrome Operation

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Growth Dynamics and Optimal Harvesting Stage of Two Forage Maize Varieties

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Agricultural Sciences in China 2011年第2期10卷 220-227页

作者： FU feng-ling GUO Chang-jun TANG Qi-ling LIU Jian LI Wan-chen Maize Research Institute Sichuan Agricultural UniversityYa＇an 625014P.R.China

SAUMZ 1 and SAUMZ 2 are two forage maize varieties reproduced by distant *** a randomized block experiment,their fresh forage yield and dry matter yield were investigated on the basis of growth period,leaf stage,and effective accumulated *** nutritional components were measured in a near infrared diffuse reflectance *** to the concept of forage grading index,a formula was constructed to calculate the total digestible *** investigated characters and indexes were adapted to suitable models of growth *** results showed that these two varieties have strong heterosis in fresh forage yield,dry matter yield,and total digestible *** growth dynamics were adapted to Logistic models described by general equation y=k/（1＋ae-bx）.The forage grading indexes of these two varieties were decreased linearly along with the increasing of their leaf *** stopping point of fast growing period of total digestible energy estimated on the basis of leaf stage was suggested to be used as optimal harvesting stage of forage *** optimal harvesting stage was estimated to be tasseling stage for SAUMZ 1 and 19.50-leaf stage for SAUMZ 2.

关键词： forage maize growth dynamics leaf stage optimal harvest stage total digestible energy

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Saline soil enzyme activities of four plant communities in Sangong River basin of Xinjiang,China

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Journal of Arid Land 2014年第2期6卷 164-173页

作者： ZhengJun GUAN Qian LUO Xi chen XianWei feng ZhiXi TANG Wei WEI YuanRun ZHENG State Key Laboratory of Vegetation and Environmental Change Institute of BotanyChinese Academy of Sciences Department of Life Sciences Yuncheng University Xinjiang Institute of Ecology and Geography Chinese Academy of Sciences

Soil enzyme activity plays an important role in the conversion of soil organic carbon into inorganic carbon, which is significant for the global carbon cycle. In this study, we investigated the soil enzyme activities of two ligninolytic enzymes （peroxidase and polyphenol oxidase） and five non-ligninolytic enzymes （a-l,4-glucosidase （AG）; 13-1,4-gluco- sidase （BG）; N-acetyl-[3-glucosaminidase （NAG）; ~3-D-cellobiosidase （CBH）; and ^-xylosidase （BXYL）） in four plant communities of the Sangong River basin in Fukang, North Xinjiang, China. The four typical plant communities were dominated by Haloxylon ammodendron, Reaumuria soongonica, Salsola passerina, and Tamarix rarmosissima, respec- tively, with saline soils of varied alkalinity. The results showed that the soil peroxidase activity decreased seasonally. The activities of the five non-ligninolytic enzymes decreased with increasing soil depths, while those of the two ligninolytic enzymes did not show such a trend. In the four plant communities, BG had the highest activity among the five non-ligninolytic enzymes, and the activities of the two ligninolytic enzymes were higher than those of the four non-ligninolytic ones （AG, NAG, CBH, and BXYL）. The community of H. ammodendron displayed the highest activity with respect to the two ligninolytic enzymes in most cases, but no significant differences were found among the four plant communities. The geometric mean of soil enzyme activities of the four plant communities was validated through an inde- pendently performed principal component analysis （PCA）, which indicated that different plant communities had different soil enzyme activities. The correlation analysis showed that soil polyphenol oxidase activity was significantly positively correlated with the activities of the five non-ligninolytic enzymes. The soil pH value was positively correlated with the ac- tivities of all soil enzymes except peroxidase. Soil microbial carbon content also showed a significant positive cor

关键词： soil enzyme activity saline soil Haloxylon ammodendron Reaumuria soongonica Salsola passerina Tamafix rarmosissima

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Self-crosslinkable chitosan-hyaluronic acid dialdehyde nanoparticles for CD44-targeted siRNA delivery to treat bladder cancer

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Bioactive Materials 2021年第2期6卷 433-446页

作者： Ye liang Yonghua Wang Liping Wang Zhijuan liang Dan Li Xiaoyu Xu Yuanbin chen Xuecheng Yang Hongbo Zhang Haitao Niu Key Laboratory of Urology and Andrology Medical Research CentreAffiliated Hospital of Qingdao UniversityQingdao266003China Department of Urology Affiliated Hospital of Qingdao UniversityQingdao266003China Pharmaceutical Sciences Laboratory and Turku Bioscience Centre Åbo Akademi UniversityTurku20520Finland

Bladder cancer is one of the concerning malignancies worldwide,which is lacking effective targeted *** therapy is a potential approach for bladder cancer ***,a safe and effective targeted gene delivery system is urgently needed for prompting the bladder cancer treatment in *** this study,we confirmed that the bladder cancer had CD44 overexpression and small interfering RNAs(siRNA)with high interfere to Bcl2 oncogene were designed and *** hyaluronic acid dialdehyde(HAD)was prepared in an ethanol-water mixture and covalently conjugated to the chitosan nanoparticles(CS-HAD NPs)to achieve CD44 targeted siRNA *** in vitro and in vivo evaluations indicated that the siRNA-loaded CS-HAD NPs(siRNA@CS-HAD NPs)were approximately 100 nm in size,with improved stability,high siRNA encapsulation efficiency and low ***-HAD NPs could target to CD44 receptor and deliver the therapeutic siRNA into T24 bladder cancer cells through a ligand-receptor-mediated targeting mechanism and had a specific accumulation capacity in vivo to interfere the targeted oncogene Bcl2 in bladder ***,a CD44 targeted gene delivery system based on natural macromolecules was developed for effective bladder cancer treatment,which could be more conducive to clinical application due to its simple preparation and high biological safety.

关键词： siRNA delivery Chitosan Hyaluronic acid dialdehyde CD44 targeting Bladder cancer

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Controlled fabrication and electrical-magnetic properties of Poly(OT-co-AN)/Ba_(0.8)La_(0.2)Al_2Fe_(10)O_(19) composites

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Science China(Technological Sciences) 2012年第1期55卷 6-15页

作者： chen KeYu XU QingQing LI liangChao TONG GuoXiu QIAN HaiSheng XIAO QiuShi XU feng Department of Chemistry Institute of Physical Chemistry Zhejiang Normal University Jinhua 321004 China

Poly（OT-co-AN）/Ba0.8La0.2Al2Fe10O19 （Poly（OT-co-AN）/BLAF） composites were fabricated by in situ polymerization method. It was investigated that of mass rate of momomer （mor/mAN）, polymeration temperature and time, and feeding ratio of BLAF effect on the structures, morphology, conductivity, magnetic property of composites by the orthogonal optimum design. The results indicated that poly （OT-co-AN） copolymer had a better coating on BLAF particles, and there were some interactions between components in the composites. The magnetic properties of the composites were related to content of the magnetic BLAF particles in it. The feeding ratio of BLAF had a significant influence on constitute and conductivity of the composites, followed by the temperature. The reflection loss and the effective bandwidth of composites for electromagnetic wave were at- tributed to the synergistic effect between poly（OT-co-AN） and BLAF. The poly（OT-co-AN）/BLAF composites with mass ratio of BLAF to mix monomer （moT^mAN =1：1） equal to 5/1 at 10 h in 25~C had a maximum synergistic effect between its compo- nents, showed a maximum reflection loss of -26.94 dB at 14.10 GHz and an available bandwidth of 8.54 GHz. It was sug- gested that the composites can be used as a advancing absorption and shielding materials for electromagnetic wave due to their favorable microwave absorption properties.

关键词： poly(OT-co-AN) copolymer Ba-ferrite conductivity magnetic property reflection loss

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New Inorganic-organic Hybrid Compound Containing One Dimensional Keggin Polyoxometalate [SiW_(11)O_(39)Co]^(6-) Chains: Preparation, Characterization and Application in Chemically Bulk-modified Electrode

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Chemical Research in Chinese Universities 2008年第2期24卷 129-134页

作者： WANG Xiu-li LIN Hong-yan LIUGuo-cheng chen Bao-kuan BI Yan-feng Faculty of Chemistry and Chemical Engineering Bohai University Liaoning Key Laboratry of Applied Chemistry Jinzhou 121000 P. R. China

A new inorganic-organic hybrid compound based on polyoxometalate and organic ligand formulated as （H2bpp）3[SiWlIO39Co]-2H20（1）[bpp=l,3-bis（4-pyridyl）propane] was hydrothermally synthesized and structurally characterized by elemental analysis, single-crystal X-ray diffraction, IR, TG, and cyclic voltammetry. Single-crystal X-ray diffraction analysis reveals that compound 1 consists of interesting cobalt-monosubstituted POMs one dimensional chain together with protonated bpp ligands. Additionally, the polyoxoanions combined with the discrete organic substrates by hydrogen bond interactions to afford a supramolecular 3D network structure. The hybrid compound 1 was used as a bulk modifier to fabricate a three-dimensional chemically modified carbon paste electrode（1-CPE） by direct mixing. The electrochemical behavior and electrocatalysis of 1-CPE were studied in detail. The results indicate that 1-CPE has good electrocatalytic activities toward the reduction of nitrite or bromate in 1 mol/L 1-12SO4 aqueous solution. 1-CPE shows remarkable stability that can be ascribed to the insolubility of compound 1 and the supramolecular interactions existed between 1D POM anion chains and organic ligand bpp, which is very important for practical applications in electrode modification.

关键词： Inorganic-organic hybrid Polyoxometalate Electrochemistry Carbon paste electrode Electrocatalysis

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