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Global influenza surveillance with Laplacian multidimensional scaling

Frontiers of Information Technology & Electronic Engineering 2016年第5期17卷 413-421页

作者： Xi-chuan ZHOU Fang TANG Qin li Sheng-dong HU Guo-jun li Yun-jian JIA Xin-ke li Yu-jie feng College of Communications Engineering Chongqing University Chongqing 400044 China MOE Key Laboratory of Dependable Service Computing in Cyber Physical Society Chongqing 400044 China Chongqing Engineering Laboratory of High Performance Integrated Circuits Chongqing University Chongqing 400044 China Centers for Disease Control and Prevention of Chongqing Chongqing 400042 China Chongqing Communication Institute Chongqing 400030 China Third Military Medical University Southwest Hospital Chongqing 400030 China

The Global Influenza Surveillance Network is crucial for monitoring epidemic risk in participating countries. However, at present, the network has notable gaps in the developing world, principally in Africa and Asia where laboratory capabilities are limited. Moreover, for the last few years, various influenza viruses have been continuously emerging in the resource-limited countries, making these surveillance gaps a more imminent *** present a spatial-transmission model to estimate epidemic risks in the countries where only partial or even no surveillance data are available. Motivated by the observation that countries in the same influenza transmission zone divided by the World Health Organization had similar transmission patterns, we propose to estimate the influenza epidemic risk of an unmonitored country by incorporating the surveillance data reported by countries of the same transmission zone. Experiments show that the risk estimates are highly correlated with the actual influenza morbidity trends for African and Asian countries. The proposed method may provide the much-needed capability to detect, assess, and notify potential influenza epidemics to the developing world.

关键词： Surveillance gap Influenza Spatial-transmission model

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Air target recognition method against ISRJ for radio frequency proximity sensors using chaotic stream encryption

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Defence Technology（防务技术） 2023年第10期28卷 267-279页

作者： Jian-feng li Jian Dai Xin-hong Hao Xiao-peng Yan Xin-wei Wang Science and Technology on Electromechanical Dynamic Control Laboratory School of Mechatronical EngineeringBeijing Institute of TechnologyBeijing100081China BIT Tangshan Research Institute Beijing100081China

The interrupted-sampling repeater jamming(ISRJ)can cause false targets to the radio-frequency proximity sensors(RFPSs),resulting in a serious decline in the target detection capability of the *** article proposes a recognition method for RFPSs to identify the false targets caused by *** proposed method is realized by assigning a unique identity(ID)to each RFPS,and each ID is a periodically and chaotically encrypted in every pulse *** processing technique of the received signal is divided into ranging and ID *** the ranging part,a high-resolution range profile(HRRP)can be obtained by performing pulse compression with the binary chaotic *** suppress the noise,the singular value decomposition(SVD)is applied in the *** ID decryption,targets and ISRJ can be recognized through the encryption and decryption processes,which are controlled by random *** adaptability analysis conducted in terms of the peak-to-side lobe ratio(PSLR)and bit error rate(BER)indicates that the proposed method performs well within a 70-k Hz Doppler shift.A simulation and experimental results show that the proposed method achieves extremely stable target and ISRJ recognition accuracies at different signal-to-noise ratios(SNRs)and jamming-to-signal ratios(JSRs).

关键词： Interrupted-sampling repeater jamming(ISRJ) Radio frequency proximity sensors(RFPS) Chaotic stream encryption Air target recognition Identity(ID)decryption

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Pre-heating temperature induced flowability and wax deposition characteristics of crude oil adding wax inhibitors

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Petroleum Science 2023年第4期20卷 2468-2478页

作者： Bo Yao Hao-Ran Zhu Bao-Dong Yan Chuan-xian li Fei Yang Guang-Yu Sun Hong-Bo Zeng College of Pipeline and Civil Engineering China University of PetroleumQingdaoShandong266580People's Republic of China Department of Chemical and Materials Engineering University of AlbertaEdmontonABT6G 1H9Canada School of Petroleum Engineering Changzhou UniversityChangzhouJiangsu213164People's Republic of China China Oil&Gas Pipeline Network Corporation Beijing100020China

This paper investigated the effects of pre-heating treatment temperatures(T_(pre))on the flowability and wax deposition characteristics of a typical waxy crude oil after adding wax *** is found that there is little difference in wax precipitation exothermic characteristics of crude oils at different T_(pre),as well as the wax crystal solubility coefficient in the temperature range of 25-30℃.For the undoped crude oil,the flowability after wax precipitation gets much improved and the wax deposition is alleviated as T_(pre)*** T_(pre)=50℃,the viscosity and wax deposition rate of crude oil adding wax inhibitors are higher than those of the undoped crude *** the T_(pre)increases to 60,70,and 80℃,the flowability of the doped crude oil are largely improved and the wax deposition is suppressed with the T_(pre)increase,but the wax content of wax deposit increases *** is speculated that,on the one hand,the T_(pre)increase helps the dispersion of asphaltenes into smaller sizes,which facilitates the co-crystallization with paraffin waxes and generates more aggregated wax crystal *** weakens the low-temperature gel structure and increases the solid concentration required for the crosslink to form the wax *** the other hand,the decrease in viscosity increases the diffusion rate of wax molecules and accelerates the aging of wax *** experimental results have important guiding significance for the pipeline transportation of doped crude oils.

关键词： Pre-heating treatment Wax inhibitor Flowability Wax deposition Waxy crude oil

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Effect of Hydrological Connectivity on Soil Carbon Storage in the Yellow River Delta Wetlands of China

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Chinese Geographical Science 2021年第2期31卷 197-208页

作者： feng Jiuge liANG Jinfeng li Qianwei ZHANG Xiaoya YUE Yi GAO Junqin School of Ecology and Nature Conservation Beijing Forestry UniversityBeijing 100083China State Key Laboratory of Water Environment Simulation School of EnvironmentBeijing Normal UniversityBeijing 100875China The Key Laboratory of Ecological Protection in the Yellow River Basin of National Forestry and Grassland Administration

Hydrological connectivity has significant effects on the functions of estuarine wetland *** study aimed to examine the dynamics of hydrological connectivity and its impact on soil carbon pool in the Yellow River Delta,*** calculated the hydrological connectivity based on the hydraulic resistance and graph theory,and measured soil total carbon and organic carbon under four different hydrological connectivity gradients(Ⅰ0‒0.03,Ⅱ0.03‒0.06,Ⅲ0.06‒0.12,Ⅳ0.12‒0.39).The results showed that hydrological connectivity increased in the north shore of the Yellow River and the south tidal flat from 2007 to 2018,which concentrated in the mainstream of the Yellow River and the tidal *** hydrological connectivity was maintained in the wetland restoration *** soil total carbon storage and organic carbon storage significantly increased with increasing hydrological connectivity fromⅠtoⅢgradient and decreased inⅣ*** highest soil total carbon storage of 0‒30 cm depth was 5172.34 g/m^(2),and organic carbon storage 2764.31 g/m^(2)inⅢ*** hydrological connectivity changed with temporal and spatial change during 2007‒2018 and had a noticeable impact on soil carbon storage in the Yellow River *** results indicated that appropriate hydrological connectivity,i.e.0.08,could effectively promote soil carbon storage.

关键词： coastal wetland hydrological connectivity soil carbon carbon storage spatiotemporal variation the Yellow River Delta

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Preparation of dynamic polyurethane networks with UV-triggered photothermal self-healing properties based on hydrogen and ion bonds for antibacterial applications

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Journal of Materials Science & Technology 2023年第2期133卷 89-101页

作者： Huimeng feng Wei Wang Tong Wang Lei Zhang Wen li Jue Hou Shougang Chen School of Materials Science and Engineering Ocean University of ChinaQingdao 266100China

Photo-induced self-healing composites have attracted more and more attention as a kind of materials that can be controlled remotely and accurately in real ***,we report a strategy of a photo-responsive system based on hydrogen and ion bonds capable of performing self-healing process by ultraviolet wave-lengths,which is covalently cross-linked zinc-dimethylglyoxime-polyurethane coordination network with triple dynamic *** recombination of hydrogen bond and metal coordination bond produces ef-fective healing *** self-healing behavior and temperature dependence of 3D micro-crack is investigated by molecular dynamics simulations to reveal the mechanism of self-healing at molecu-lar ***,the hybrid of copper-doped zinc oxide not only provides metal coordination bonds to enhance the self-healing rate,but also enhances the photothermal effect and anti-bacterial properties of ***,doping of copper generates more defects and forms a space charge layer on the surface of zinc *** defects could trap surface electrons and holes,preventing the recom-bination of photo-induced electron-hole pairs,generating more heat through lattice ***,under ultraviolet light irradiation,the polyurethane can reach 62.7°C for 60 s,and the scratches of the polyurethane can be healed within 30 min and fully healed within 1 h.

关键词： Cu-dopped ZnO Ionic bond Photothermal Self-healing Antibacterial

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Minimally invasive endoscopic repair of rectovaginal fistula

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World Journal of Gastrointestinal Surgery 2022年第9期14卷 1049-1059页

作者： Yi-xian Zeng Ying-Hua He Yun Jiang Fei Jia Zi-Ting Zhao Xiao-feng Wang Department of Proctology Guang’anmen HospitalChina Academy of Chinese Medical SciencesBeijing 100053China

BACKGROUND Surgical techniques for repair of rectovaginal fistula(RVF)have been continually developed,but the ideal procedure remains *** repair is a novel and minimally invasive technique for RVF repair with increasing *** To review the current applications and preliminary outcomes of this technique for RVF repair,aiming to give surgeons an alternative in clinical *** Available articles were searched according to the search *** the sample size,fistula etiology,fistula type,endoscopic repair approaches,operative time and hospital stay,follow-up period,complication and life quality assessment were selected for recording and further *** A total of 11 articles were eventually identified,involving 71 patients with RVFs who had undergone endoscopic *** principal causes of RVFs were surgery(n=51,71.8%),followed by obstetrics(n=7,9.8%),inflammatory bowel disease(n=5,7.0%),congenital(n=3,4.2%),trauma(n=2,2.8%),radiation(n=1,1.4%),and in two patients,the cause was *** fistulas were in a mid or low *** endoscopic repair methods were included,namely transanal endoscopic microsurgery,endoscopic clipping,and endoscopic *** patients underwent>1-year follow-up,and the success rate was 40%-93%,and all cases reported successful *** complications were mentioned,while postoperative quality of life assessment was only mentioned in one *** In conclusion,endoscopic repair of RVF is novel,minimally invasive and promising with acceptable preliminary *** its unique advantages,endoscopic repair can be an alternative technique for surgeons.

关键词： Endoscopic repair Minimal-invasive technique Rectovaginal fistula

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Identification and activity evaluation of Astragalus Radix from different germplasm resources based on specific oligosaccharide fragments

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Chinese Herbal Medicines 2021年第1期13卷 33-42页

作者： Shu-ying li Di Wang xian-rong li Xue-mei Qin Yu-guang Du Ke li National Glycoengineering Research Center Shandong Key Laboratory of Carbohydrate Chemistry and GlycobiologyShandong UniversityQingdao 266237China Modern Research Center for Traditional Chinese Medicine Shanxi UniversityTaiyuan 030006China College of Chemistry and Chemical Engineering Shanxi UniversityTaiyuan 030006China Shanxi Jianshuo Food and Drug Research Institute Co. Ltd.Taiyuan 030000China Shanxi Academy of Traditional Chinese Medicine Taiyuan 030000China Institure of Process Engineering Chinese Academy of SciencesBeijing 100190China

Objective: Based on trifluoroacetic acid(TFA) hydrolysis, polyacrylamide gel electrophoresis(PAGE) and high performance thin layer chromatography(HPTLC) analysis, the carbohydrate responsible for immunomodulatory activity are used as quality indicators for Astragalus Radix(AR).Methods: In this study, 24 batches of AR from different germplasm resources were selected as the research object, and AR polysaccharides were extracted. PAGE and HPTLC methods were used to analyze the partial acid hydrolyzate of AR polysaccharides and obtain a series of saccharide fingerprints. The data were analyzed by principal component analysis to obtain the difference between AR from different germplasm ***: The results showed that trisaccharide and tetrasaccharide could be used as differential fragments to distinguish AR of different cultivation methods;Disaccharides and trisaccharides can be used as differential fragments to distinguish different species of AR. The immunological activity analysis of the specific oligosaccharide fragment of AR showed that the specific oligosaccharide fragment of AR could promote the secretion of TNF-α, IL-1β, IL-6, and NO in THP-1 cells in a concentration-dependent ***: Both PAGE and HPTLC methods can be used to evaluate AR from different germplasm resources. This study laid the foundation for the quality evaluation of AR medicinal herbs.

关键词： Astragalus Radix germplasm resources hydrolyzate polysaccharide saccharide fingerprints

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Theoretical study on the reaction of NbS^+(~3∑^-,~1Γ) with CO

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Chinese Chemical Letters 2009年第6期20卷 755-758页

作者： Shi Wen Yu TaoHong li Xiao Mei Yang li Qing Yin li feng Yao Xiao Guang Xie Department of Chemistry Yunnan University Kunming 650091 China Department of Chemistry Qujing Normal University Qujing 650011 China Faculty of Chemistry Southwest Forestry University Kunming 650224 China Yunnan University of Traditional Chinese Medicine Kunming 650091 China

Two possible reactions of NbS＋（3∑^-, 1Г） with CO in the gas phase have been studied by using B3LYP and CCSD（T） methods： the O/S exchange reaction （NbS^＋＋ CO → NbO^＋＋ CS） and the S-transfer reaction （NbS＋＋ CO → Nb^＋＋ COS）. The two reactions have a one-step mechanism. The barriers of the O/S exchange reaction on the triplet and singlet surfaces are 51.2 and 52.4 kcal/mol, respectively, and the barriers of the S-transfer reaction are 58.3 and 78.0 kcal/mol, respectively. The results indicate that the Stransfer and the O/S exchange reaction of the 3∑^- ground state of NbS＋ are competing, but, for the S-transfer reaction, the 1F exited state is more reactive. The differences between the reactions of NbS＋（3∑^_, 1Г） and VS＋（3∑^_, 1Г） are discussed.

关键词： Niobium sulfide cation CO Reaction CCSD(T)

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Research of Current Mode Atomic Force Microscopy (C-AFM) for Si/SiC Heterostructures on 6H-SiC(0001)

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Journal of Beijing Institute of Technology 2020年第2期29卷 184-189页

作者： Song feng lixun Song Yuan Zang Zheyan Tu lianbi li School of Science Xi’an Polytechnic UniversityXi’an 710048China Department of Electronic Engineering Xi’an University of TechnologyXi’an 710048China

Si/SiC heterostructures with different growth temperatures were prepared on 6 HSiC(0001)by *** mode atomic force microscopy and transmission electron microscopy were employed to investigate the electrical properties and crystalline structure of Si/SiC ***-centered cubic(FCC)on hexagonal close-packing(HCP)epitaxy of the Si(111)/SiC(0001)heterostructure was realized at 900°*** the growth temperature increases to1050°C,thepreferred orientation of the Si film is *** Si films on 6 H-SiC(0001)with different growth orientations consist of different distinctive crystalline grains:quasi-spherical grains with a general size of 20μm,and columnar grains with a typical size of 7μm×20μ*** electrical properties are greatly influenced by the grain *** Si film withorientation on SiC(0001)consists of columnar grains,which is more suitable for the fabrication of Si/SiC devices due to its low current fluctuation and relatively uniform current distribution.

关键词： Si/6H-SiC heterostructure electrical properties current mode AFM chemical vapor deposition

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Three-in-one DNA nanowheels for simultaneous tumor regression and drug resistance prevention in breast cancer model

Advanced Sensor and Energy Materials

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Advanced Sensor and Energy Materials 2024年第3期3卷 2-10页

作者： Ping li Chun-feng feng Peng-Fei Lyu Fei liu Hui-Sheng li li-Qun Zhang Department of Maxillofacial and Ear Nose and Throat OncologyTianjin Medical University Cancer Institute and HospitalNational Clinical Research Center for CancerKey Laboratory of Basic and Translational Medicine on Head&Neck CancerTianjinChina Department of Clinical Laboratory The Second Affiliated HospitalArmy Medical UniversityChongqingChina Department of Breast Oncology Department Tianjin Medical University Cancer Institute and HospitalTianjinChina

Herein,we proposed novel three-in-one DNA nanowheels with simultaneous chemo and gene therapy to treat tumor,especially to prevent simultaneous drug resistance,which could be disassembled via a cascaded hybridization reactions triggered by the highly expressed microRNA in cancer cells for smart and efficient cancer ***,with breast cancer as a model,microRNA 21 could trigger the self-disassembly of DNA nanowheel 1 via hybridization with a specially designed oligonucleotide(anti-microRNA 21)in DNA nanowheel 1,releasing another special oligonucleotide(Contact sequence)to trigger the self-disassembly of DNA nanowheel 2 with releasing of a special oligonucleotide(anti-Contact sequence)to trigger the self-disassembly of DNA nanowheel 1 cyclically,and thus the cascaded hybridization reactions with three-in-one anti-cancer functions could be generated based on three main therapeutic effects via releasing doxorubicin to inhibit macromolecular biosynthesis,antisense oligonucleotide of microRNA 21 to activate the apoptotic cell pathway and antisense oligonucleotide of MDR1 to prevent the drug resistance *** expected,the proposed method showed improved therapeutic efficacy on the cancer cells with about 80%apoptosis ratio,especially on the drug resistant cancer cells with about 75%apoptosis ratio,compared with that in the conventional anti-cancer systems of about 70%on cancer cells and below 40%on drug resistant cancer cells,*** importantly,this strategy opened the door for generation of complex functional DNA-based structures for target triggering drugs releasing system combining with chemo-and genetherapy to generate tumor regression and prevent drug resistance with an optimized therapeutic efficacy,providing a new avenue for efficient cancer treatment,especially drug resistant cancers.

关键词： DNA machine Drug resistance Multi-combination strategy Self-disassembly

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