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Prevalence and risk factors of osteoporosis detected by dual-energy X-ray absorptiometry among Chinese patients with primary biliary cholangitis

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World Journal of Gastroenterology 2023年第29期29卷 4580-4592页

作者： Jia-Liang Chen Yao Liu Yu-Fei Bi Xian-Bo Wang Center of Integrative Medicine Beijing Ditan HospitalCapital Medical UniversityBeijing 100015China

BACKGROUND Osteoporosis is an extrahepatic complication of primary biliary cholangitis(PBC)that increases the risk of fractures and mortality.However,Epidemiological studies of osteoporosis in patients with PBC in China and the Asia-Pacific region is lack.AIM To assess the prevalence and clinical characteristics of osteoporosis in Chinese patients with PBC.METHODS This retrospective analysis included consecutive patients with PBC from a tertiary care center in China who underwent bone mineral density(BMD)assessment using dual-energy X-ray absorptiometry between January 2013 and December 2021.We defined subjects with T-scores≤-2.5 in any sites(L1 to L4,femoral neck,or total hip)as having osteoporosis.Demographic,serological,clinical,and histological data were collected.Independent risk factors for osteoporosis were identified by multivariate logistic regression analysis.RESULTS A total of 268 patients with PBC[236 women(88.1%);mean age,56.7±10.6 years;163 liver biopsies(60.8%)]were included.The overall prevalence of osteoporosis in patients with PBC was 45.5%(122/268),with the prevalence of osteoporosis in women and men being 47.0%and 34.4%,respectively.The prevalence of osteoporosis in postmenopausal women was significantly higher than that in premenopausal women(56.3%vs 21.0%,Pbilirubin,platelet and prothrombin activity.Multivariate regression analysis identified that older age,lower BMI,previous steroid therapy,higher Mayo risk score,and advanced histological stage as the main independent risk factors for osteoporosis in PBC.CONCLUSION Osteoporosis is very common in Chinese patients with PBC,allowing for prior screening of BMD in those PBC patients with older age,lower BMI,previous steroid therapy and advanced liver disease.

关键词： Primary biliary cholangitis Osteoporosis Bone mineral density Dual-energy X-ray absorptiometry Prevalence Chinese

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Simulation of proton–neutron collisions in inverse kinematics and its possible application

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Nuclear Science and Techniques 2021年第4期32卷 60-69页

作者： bi-Lu Li Gang-Lin yu Shi-fei Shen Department of Engineering Physics Tsinghua UniversityBeijing 100084China

Neutrons have played a vital role in many nuclear physics fields.In some cases,the inverse kinematics of neutrons colliding with other nuclei are also worth studying.In this study,the inverse kinematics of thermal neutrons colliding with high-energy protons is simulated by using the Monte Carlo method.Thermal neutrons are taken as target particles,whereas protons are incident particles.The simulation implies that,after collision,the energy of the output neutron at 0°equals the energy of the incident proton.A possible application of the result is proposed that might yield single-energy neutrons.Some key parameters of the conceptual design were evaluated,demonstrating that the design may reach high-neutron-energy resolution.

关键词： Inverse kinematics Mono-energetic neutron Proton Monte Carlo

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Computational Experiments for Complex Social Systems:Integrated Design of Experiment System

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IEEE/CAA Journal of Automatica Sinica 2024年第5期11卷 1175-1189页

作者： Xiao Xue Xiangning yu Deyu Zhou Xiao Wang Chongke bi Shufang Wang fei-yue Wang College of Intelligence and Computing Tianjin UniversityTianjin 300350China School of Software Shandong UniversityJinan 250101China School of Artificial Intelligence Anhui UniversityHefei 230601China School of Geographic and Environmental Sciences Tianjin Normal UniversityTianjin 300387China Institute of Automation Chinese Academy of Sciences Beijing 100190China

Powered by advanced information industry and intelligent technology,more and more complex systems are exhibiting characteristics of the cyber-physical-social systems(CPSS).And human factors have become crucial in the operations of complex social systems.Traditional mechanical analysis and social simulations alone are powerless for analyzing complex social systems.Against this backdrop,computational experiments have emerged as a new method for quantitative analysis of complex social systems by combining social simulation(e.g.,ABM),complexity science,and domain knowledge.However,in the process of applying computational experiments,the construction of experiment system not only considers a large number of artificial society models,but also involves a large amount of data and knowledge.As a result,how to integrate various data,model and knowledge to achieve a running experiment system has become a key challenge.This paper proposes an integrated design framework of computational experiment system,which is composed of four parts:generation of digital subject,generation of digital object,design of operation engine,and construction of experiment system.Finally,this paper outlines a typical case study of coal mine emergency management to verify the validity of the proposed framework.

关键词： artificial system operations

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克隆植物蛇莓对光照强度和养分条件的适应性可塑性

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Journal of Plant Ecology 2022年第4期15卷 795-807页

作者： Mo-Zhu Wang Hong-Li Li Chun-Xiang Liu bi-Cheng Dong fei-Hai yu Institute of Wetland Ecology&Clone Ecology Zhejiang Provincial Key Laboratory of Plant Evolutionary Ecology and ConservationTaizhou UniversityTaizhou 318000China School of Ecology and Nature Conservation Beijing Forestry UniversityBeijing 100083China State Key Laboratory of Systematic and Evolutionary Botany Institute of BotanyChinese Academy of SciencesBeijing 100093China

表型可塑性可帮助植物缓冲环境压力并使其表型与当地环境相匹配,但目前仅少数性状的可塑性被广泛认为是适应性的。为充分理解可塑性的适应性意义,仍需进一步研究更多的植物功能性状及其环境因子。本研究将匍匐茎克隆植物蛇莓(Duchesnea ... 详细信息

表型可塑性可帮助植物缓冲环境压力并使其表型与当地环境相匹配,但目前仅少数性状的可塑性被广泛认为是适应性的。为充分理解可塑性的适应性意义,仍需进一步研究更多的植物功能性状及其环境因子。本研究将匍匐茎克隆植物蛇莓(Duchesnea indica)的21个基因型种植于不同的光照和养分条件下,并利用选择梯度分析检测了形态和生理可塑性对光照强度和养分有效性变化的适应性值。在遮荫条件下,蛇莓适合度(果实数、分株数和生物量)降低,节间缩短变细,成熟叶叶绿素含量降低,但叶柄长度、比叶面积、老叶叶绿素含量均增加。在低养分条件下,植株叶柄缩短,叶面积缩小变厚,叶绿素含量降低,但果实数量和根冠比增加。选择梯度分析表明,叶柄长度和老叶叶绿素含量对光照变化的可塑性是适应性的,老叶和成熟叶叶绿素含量对养分变化的可塑性也是适应性的。因此,不同性状的可塑性适应值取决于特定的生态背景。该研究的发现有助于理解克隆植物表型可塑性响应环境变化的适应性意义。

关键词：适应性可塑性克隆植物蛇莓(Duchesnea indica) 匍匐茎植物表型

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Online Learning a binary Classifier for Improving Google Image Search Results

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自动化学报 2014年第8期40卷 1699-1708页

作者： WAN yu-Chai LIU Xia-bi HAN fei-fei TONG Kun-Qi LIU yu Beijing Laboratory of Intelligent Information Technology School of Computre Science Beijing Institute of Technology Bei- jing 100081 China

It is promising to improve web image search results through exploiting the results0 visual contents for learning a binary classifier which is used to refine the results0 relevance degrees to the given query. This paper proposes an algorithm framework as a solution to this problem and investigates the key issue of training data selection under the framework. The training data selection process is divided into two stages: initial selection for triggering the classifier learning and dynamic selection in the iterations of classifier learning. We investigate two main ways of initial training data selection, including clustering based and ranking based, and compare automatic training data selection schemes with manual manner. Furthermore, support vector machines and the max-min pseudo-probability (MMP) based Bayesian classifier are employed to support image classification, respectively. By varying these factors in the framework, we implement eight algorithms and tested them on keyword based image search results from Google search engine. The experimental results confirm that how to select the training data from noisy search results is really a key issue in the problem considered in this paper and show that the proposed algorithm is effective to improve Google search results, especially at top ranks, thus is helpful to reduce the user labor in finding the desired images by browsing the ranking in depth. Even so, it is still worth meditative to make automatic training data selection scheme better towards perfect human annotation.

关键词：搜索结果在线学习二元分类贝叶斯分类器算法框架训练数据图片支持向量机

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Effects of soil substrate heterogeneity and moisture on interspecific competition between Alternanthera philoxeroides and four native species

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Journal of Plant Ecology 2017年第3期10卷 528-537页

作者： Lu Liu bi-Cheng Dong Peter Alpert fei-Hai yu School of Nature Conservation Beijing Forestry UniversityQinghua East Road 35Haidian DistrictBeijing 100083China biology Department University of MassachusettsAmherstMA 01003USA

Aims Clonal plant species have the potential for high relative performance in heterogeneous environments,and this might increase the com-petitive ability and invasiveness of introduced clonal plant species.It was hypothesized that clonal species whose performance responds more to heterogeneity of a resource have higher competitive ability in habitats where this resource is more heterogeneous and that this relationship is stronger when other resources are less limiting.Methods To test these hypotheses,the perennial clonal herb Alternanthera philoxeroides,which is invasive in China,was grown alone or with each of four clonal perennial,co-occurring herbs native to China,i.e.Alternanthera sessilis,Cynodon dactylon,Hemarthria altissima and Wedelia chinensis.Plants were given homogeneous or het-erogeneous soil substrate crossed with low and high levels of soil moisture.Important Findings Effects of heterogeneity on the accumulation of mass and ramets and on competitive effect and response of A.philoxeroides differed between native species and interacted with effects of soil moisture.A.philoxeroides reduced the final total mass or ramet number of the native species except A.sessilis,and the negative competitive effects on H.altissima and C.dactylon were more pronounced in heterogeneous than in homogeneous soil.Competitive response of A.philoxeroides was more negative to A.sessilis than to the other native species.Across native species,the competitive response of A.philoxeroides was more negative in heterogeneous than in homo-geneous soils at low moisture level,but the reverse was true at high moisture level.Results do not consistently support either hypoth-esis,but do suggest that competitive ability can be partly explained by individual species traits such as size,and that some competi-tive effects and responses are emergent properties of interspecific interactions.

关键词： alligator weed clonal plant competitive effect competitive response soil heterogeneity soil moisture foraging behavior

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The use of widely targeted metabolite profiling to reveal the senescence changes in postharvest 'Red Globe'(Vitis vinifera) grape berries

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Journal of Integrative Agriculture 2022年第4期21卷 1028-1043页

作者： XU Teng-fei YANG Xin ZHANG Meng GUO Shui-huan FU Wen-jing ZHOU bi-jiang LIU yu-jia MA Hai-jun FANG yu-lin YANG Gang MENG Jiang-fei College of Horticulture Northwest A&F UniversityYangling 712100P.R.China College of Enology Northwest A&F UniversityYangling 712100P.R.China College of biological Science and Engineering North Minzu UniversityYinchuan 750021P.R.China Shenzhen Camartina Wine Co. Ltd.Shenzhen 518031P.R.China

Changes in the metabolites of table grapes(Vitis vinifera) reportedly occur during postharvest senescence. The aim of this study was to determine the metabolomic differences in postharvest table grapes(‘Red Globe’) after being subjected to different senescence periods. To this end, we used widely targeted metabolomics based on ultra-performance liquid chromatography and tandem mass spectrometry. A total of 135 differential metabolites were identified. During postharvest senescence, the levels of most differential flavonoids(e.g., pelargonidin 3-O-glucoside, quercetin-3-O-glucoside, and cyanidin 3-O-glucoside) and L-aspartic acid decreased, while the levels of phenolic acids(e.g., trans-4-hydroxycinnamic acid methyl ester) and pantothenol increased. During early and late senescence, the levels of most differential lipids, especially LysoPC, as well as those of nucleotides and their derivatives, such as uridine, decreased and increased, respectively. Collectively, the findings of this study provide fundamental insights into the reasonable control of table grape fruit postharvest senescence and lay a solid foundation for further research.

关键词： table grape berry postharvest senescence widely targeted metabolites

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A Highly Efficient Luminescent Metal-Organic Framework with Strong Conjugate Unit for Sensing Small Molecules

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Chinese Journal of Chemistry 2022年第11期40卷 1305-1312页

作者： bi-Lian Chai Hui Xu Teng-fei Zheng Jing-Lin Chen Sui-Jun Liu Mei-Hui yu He-Rui Wen School of Chemistry and Chemical Engineering Jiangxi Provincial Key Laboratory of Functional Molecular Materials ChemistryJiangxi University of Science and TechnologyGanzhouJiangxi 341000China School of Materials Science and Engineering TKL of Metal-and Molecule-Based Material Chemistry and Collaborative Innovation Center of Chemical Science and Engineering(Tianjin)Nankai UniversityTianjin 300350China

Luminescent metal-organic frameworks(LMOFs)have become a promising class of fluorescence sensing materials,however,the multi-responsive LMOF sensors for organic compounds are rather rare.Herein,a water stable and highly efficient luminescent MOF with the formula of{[Zn(BBZB)(2,6-NDC)]-solvents}n(JXUST-10,BBZB=4,7-bis(1H-benzimidazole-1-yl)-2,1,3-benzothiadiazole and 2,6-NDC=2,6-naphthalenedicarboxylate)was constructed by the incorporation of Zn2+and two organic ligands(BBZB and 2,6-NDC)featuring the conjugate system.JXUST-10 is a three-dimensional two-fold interpenetrated framework with good fluorescent proper-ty.Based on the luminescent characteristic,JXUST-10 can be used as a multi-responsive sensor for detection of three different ana-lytes including tetracycline,benzaldehyde and uric acid via different luminescent change behaviours.Remarkably,fluorescence test paper and LED light devices are used to detect analytes through the visual change of luminescence colour of JXUST-10 from blue greenish to yellow greenish under ultraviolet light(365 nm)irradiation.Furthermore,the probable sensing mechanisms for three target analytes were also discussed.

关键词： Metal-organic frameworks Sensors Luminescence Red-shift emission Turn-on effect

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Shape memory behavior of Ti–20Zr–10Nb–5Al alloy subjected to annealing treatment

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Rare Metals 2016年第11期35卷 831-835页

作者： Zhi-Guo yu Cheng-Yang Xiong Peng-fei Xue Yan Li bi-fei yuan Wen-Tao Qu School of Materials Science and Engineering Beihang University Key Laboratory of Aerospace Materials and Performance (Ministry of Education) Beihang University School of Mechanical Engineering Xi’an Shiyou University

The effects of annealing temperature on microstructures, phase transformation, mechanical properties, and shape memory effect of Ti-20Zr-10Nb-5Al alloy were investigated. X-ray diffraction（XRD） patterns show that the alloy is composed of single hexagonal ɑ＇-martensite phase for both as-rolled sample and sample annealed at773 K for 30 min, while single orthorhombic ɑ＇＇ phase exists in the samples annealed at 873 and 973 K for30 min. The optical observations indicate that the alloy is recrystallized when annealed at 873 K, and the grain size of the sample annealed at 973 K is about five times larger than that annealed at 873 K. Both of the samples annealed at 873 and 973 K show almost the same reverse martensite transformation start temperature of 483 K as demonstrated by thermal dilatation tests. The critical stress values for martensite reorientation（σ_M） are 392 and 438 MPa for the alloys annealed at 873 and 973 K, respectively. The maximum shape memory strain is 2.8 %, which is obtained in the alloy annealed at 873 K due to the lower σ_M. Moreover,the sample annealed at 873 K exhibits larger tensile stress and tensile strain due to the smaller grain size.

关键词： Ti-Zr Shape memory alloy Martensitictransformation Microstructure

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Demonstration of controlled high-dimensional quantum teleportation

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Science China(Physics,Mechanics & Astronomy) 2024年第3期67卷 1-6页

作者： Min-yu Lv Xiao-Min Hu Neng-fei Gong Tie-Jun Wang yu Guo bi-Heng Liu yun-Feng Huang Chuan-Feng Li Guang-Can Guo CAS Key Laboratory of Quantum Information University of Science and Technology of ChinaHefei 230026China CAS Centerfor Excellence in Quantum Information and Quantum Physics University of Science and Technology of ChinaHefei230026China Hefei National Laboratory University of Science and Technology of ChinaHefei 230088China State Key Laboratory of Information Photonics and Optical Communications School of ScienceBeijing University of Posts and TelecommunicationsBeijing 100876China

Controlled quantum teleportation(CQT), which is regarded as the prelude and backbone for a genuine quantum internet, reveals the cooperation, supervision, and control relationship among the sender, receiver, and controller in the quantum network within the simplest unit. Compared with low-dimensional counterparts, high-dimensional CQT can exhibit larger information transmission capacity and higher superiority of the controller's authority. In this article, we report a proof-of-principle experimental realization of three-dimensional(3D) CQT with a fidelity of 97.4% ± 0.2%. To reduce the complexity of the circuit, we simulate a standard 4-qutrit CQT protocol in a 9×9-dimensional two-photon system with high-quality operations. The corresponding control powers are 48.1% ± 0.2% for teleporting a qutrit and 52.8% ± 0.3% for teleporting a qubit in the experiment, which are both higher than the theoretical value of control power in 2-dimensional CQT protocol(33%). The results fully demonstrate the advantages of high-dimensional multi-partite entangled networks and provide new avenues for constructing complex quantum networks.

关键词： high dimension quantum information quantum teleportation quantum nonlocality

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