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Frontiers of Architectural Research 2024年第2期13卷 305-318页

作者： bo wan.Dongyang wan.Qiang Sheng School of Architecture and Design Beijing Jiaotong UniversityBeijing 100044China

This paper,set against the backdrop of expanding urban rail networks and dynamic urban development,focuses on the distribution and evolution of commercial Points of Interests(POIs)within the central urban rail transit areas of *** study examines data from four different years-2008,2013,2017,and 2020-to observe the temporal evolution of commercial *** identifies stable explanatory variables affecting the distribution and evolution of commercial POIs,which include rail transit accessibility,characteristics of the working and residential population distribution around stations,and the construction intensity in the vicinity of station *** statistical analysis and model building,relatively stable linear regression equations were established,with R2 values generally maintained above 0.5(except for 2017).The study advances our understanding of the influence of rail transit on urban commercial spaces and how this influence shifts with temporal and urban developmental *** elucidates the correlation between changes in the number of businesses and spatial configuration,offering insights and information for urban planners and policy *** research also serves as a model for exploring the interplay between urban rail transit and commercial spaces in other major cities.

关键词： Urbanrail transit areas Spatial configuration Distributionand evolution of commercial POls

Spatial and temporal variation of water clarity in typical reservoirs in the Beijing-Tianjin-Hebei region observed by GF 1-WFV satellite data

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Journal of Oceanology and Limnology 2024年第4期42卷 1048-1060页

作者： Chang CAO Junsheng LI Xiaodong JIA Shenglei wan. bo wan Liaoning Earthquake Agency Shenyang 11000China Key Laboratory of Digital Earth Science Aerospace Information Research InstituteChinese Academy of SciencesBeijing 100094China International Research Center of Big Data for Sustainable Development Goals Beijing 100094China School of Electronic Electrical and Communication EngineeringUniversity of Chinese Academy of SciencesBeijing 100049China

Rapidly monitoring regional water quality and the changing trend is of great practical and scientific significance,especially for the Beijing-Tianjin-Hebei(BTH)region of China where water resources are relatively scarce and inland water bodies are generally *** remote sensing data of the GF 1 satellite launched in 2013 have characteristics of high spatial and temporal resolution,which can be used for the dynamic monitoring of the water environment in small lakes and ***,the water quality remote sensing monitoring model based on the GF 1 satellite data for lakes and reservoirs in BTH is still lacking because of the considerable differences in the optical characteristics of the lakes and *** this paper,the typical reservoirs in BTH-Guanting Reservoir,Yuqiao Reservoir,Panjiakou Reservoir,and Daheiting Reservoir are taken as the study *** the atmospheric correction of GF 1-WFV,the relative radiation normalized atmospheric correction was adopted after comparing it with other methods,such as 6 S and *** the water clarity retrieval,a water color hue angle based model was proposed and outperformed other available published models,with the R 2 of 0.74 and MRE of 31.7%.The clarity products of the four typical reservoirs in the BTH region in 2013-2019 were produced using the GF 1-WFV *** on the products,temporal and spatial changes in clarity were analyzed,and the main influencing factors for each water body were *** was found that the clarity of Guanting,Daheiting,and Panjiakou reservoirs showed an upward trend during this period,while that of Yuqiao Reservoir showed a downward *** the influencing factors,the water level of the water bodies can be an important factor related to the water clarity changes in this region.

关键词： GF 1 satellite atmospheric correction clarity Beijing-Tianjin-Hebei spatial and temporal change analysis

Pathology of pain and its implications for therapeutic interventions

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Signal Transduction and Targeted Therapy 2024年第7期9卷 2851-2899页

作者： bo Cao Qixuan Xu Yajiao Shi Ruiyang Zhao Hanghang Li Jie Zheng Fengyu Liu You wan.bo Wei Department of General Surgery First Medical CenterChinese PLA General HospitalBeijing 100853China Medical School of Chinese PLA Beijing 100853China Neuroscience Research Institute and Department of Neurobiology School of Basic Medical SciencesKey Laboratory for NeuroscienceMinistry of Education/National Health CommissionPeking UniversityBeijing 100191China

Pain is estimated to affect more than 20%of the global population,imposing incalculable health and economic *** pain management is crucial for individuals suffering from ***,the current methods for pain assessment and treatment fall short of clinical *** from advances in neuroscience and biotechnology,the neuronal circuits and molecular mechanisms critically involved in pain modulation have been *** research achievements have incited progress in identifying new diagnostic and therapeutic *** this review,we first introduce fundamental knowledge about pain,setting the stage for the subsequent *** review next delves into the molecular mechanisms underlying pain disorders,including gene mutation,epigenetic modification,posttranslational modification,inflammasome,signaling pathways and *** better present a comprehensive view of pain research,two prominent issues,sexual dimorphism and pain comorbidities,are discussed in detail based on current *** status quo of pain evaluation and manipulation is summarized.A series of improved and innovative pain management strategies,such as gene therapy,monoclonal antibody,brain-computer interface and microbial intervention,are making strides towards clinical *** highlight existing limitations and future directions for enhancing the quality of preclinical and clinical *** to decipher the complexities of pain pathology will be instrumental in translating scientific discoveries into clinical practice,thereby improving pain management from bench to bedside.

关键词： pain thereby summarized

Thiazoloisoindigo-based Polymer Semiconductors: Synthesis,Structure-Property Relationship, Charge Carrier Polarity, and Field-Effect Transistor Performance

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Chinese Journal of Polymer Science 2024年第1期42卷 24-31,I0006页

作者： bo-Wen Li Miao Xiong Mei-Hua Liu Zhi-Gao Li Long Sang Zi-Han Xiong Biao Xiao Jian Pei Xiao-bo wan Key Laboratory of Optoelectronic Chemical Materials and Devices Ministry of EducationSchoolofOptoelectronic Materials&TechnologyJianghan UniversityWuhan430056China Bejing National Laboratoryfor Molecular Sciences the Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of EducationCollege of Chemistry and Molecular EngineeringPeking UniversityBeijing 100871China

Developing new polymeric semiconductors with excellent device performance is essential for organic electronics. Herein, we synthesized two new thiazoloisoindigo(Tz II)-based polymers, namely, P(Tz II-d Th-d Th) and P(Tz II-d Th-d Tz), by copolymerizing thiophene-flanked Tz II with bithiophene and bithiazole, respectively. Owing to the more electron-deficient nature of bithiazole than bithiophene, P(Tz II-d Th-d Tz)possesses deeper LUMO/HOMO levels of-3.45/-5.47 e V than P(Tz II-d Th-d Th)(-3.34/-5.32 e V). The organic field-effect transistor(OFET) devices based on P(Tz II-d Th-d Th) exhibited p-type behaviors with an average hole mobility value as high as 1.43 cm^(2)·V^(-1)·s^(-1), while P(Tz II-d Th-d Tz)showed typical ambipolar characteristics with average hole and electron mobilities of 0.38 and 0.56 cm^(2)·V^(-1)·s^(-1). In addition, we compared the performances of both polymers with other Tz II-based polymers reported in our previous work, and showed that the charge carrier polarity can be manipulated by adjusting the number of the thiophene units between the acceptor unit. As the increase of the number of thiophene rings,charge carrier polarity shifts from electron-dominated ambipolar transport to hole-dominated ambipolar transport and then to unipolar hole transport in OFETs, which provides an effective molecular design strategy for further optimization of polymer OFET performance.

关键词： Field-effect transistor Charge carrier polarity Thiazoloisoindigo

Adverse effect of niobium and boron on hot deformation behavior of sulfur-containing steel

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Journal of Iron and Steel Research International 2024年第1期31卷 252-263页

作者： Guo-ning He Shi-qi wan.bo Jiang Chao-lei Zhang Ya-zheng Liu Chun-jing Wu School of Materials Science and Engineering University of Science and Technology BeijingBeijing100083China Institute for Advanced Materials and Technology University of Science and Technology BeijingBeijing100083China

The hot deformation behaviors of sulfur-containing gear steel 20MnCr5 containing three different contents of Nb and B(0,0.021%Nb,and 0.024%Nb-0.0022%B)were *** compression and tenssion tests were carried out by Gleeble3800 at the austenite region from 850 to 1150℃and the adverse effects of Nb and B were analyzed by the fracture,microstructure and precipitate *** compression tests showed that the proportions of instable area in hot processing maps of 0.021%Nb and Nb-B steels were higher and the deformability of Nb free steel was *** tensile deformation experiments showed that the reduction areas of Nb free,0.021%Nb and Nb-B steels were 92%-99%,84%-98%and 67%-97%,*** addition of Nb or Nb and B inhibited the dynamic recrystallization during hot deformation,and consequently,more deformed grains were then formed in 0.021%Nb and Nb-B steels thus to obtain the microstructure with worse uniformity and then deteriorate the *** addition,the interaction between inclusions and microalloyed elements was also *** particles of 0.021%Nb and Nb-B steels dynamically precipitated during deformation and precipitated together with MnS thus to worsen the deformability,resulting in the decrease of reduction area.

关键词： Hot deformation Gear steel Processing map Dynamic recrystallization Microalloying

Impact Analysis of Microscopic Defect Types on the Macroscopic Crack Propagation in Sintered Silver Nanoparticles

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Computer Modeling in Engineering & Sciences 2024年第4期139卷 441-458页

作者： Zhongqing Zhang bo wan.Guicui Fu Yutai Su Zhaoxi Wu Xiangfen wan. Xu Long School of Reliability and Systems Engineering Beihang UniversityBeijing100191China School of Mechanics Civil Engineering and ArchitectureNorthwestern Polytechnical UniversityXi’an710072China China Aerospace Components Engineering Center Beijing100098China

Sintered silver nanoparticles(AgNPs)arewidely used in high-power electronics due to their exceptional ***,the material reliability is significantly affected by various microscopic *** this work,the three primary micro-defect types at potential stress concentrations in sintered AgNPs are identified,categorized,and *** dynamics(MD)simulations are employed to observe the failure evolution of different microscopic *** dominant mechanisms responsible for this evolution are dislocation nucleation and dislocation *** the same time,this paper clarifies the quantitative relationship between the tensile strain amount and the failure mechanism transitions of the three defect types by defining key strain *** impact of defect types on the failure process is also ***,traction-separation curves extracted from microscopic defect evolutions serve as a bridge to connect the macro-scale *** validity of the crack propagation model is confirmed through tensile ***,we thoroughly analyze how micro-defect types influence macro-crack propagation and attempt to find supporting evidence from the MD *** findings provide a multi-perspective reference for the reliability analysis of sintered AgNPs.

关键词： Sintered silver nanoparticles defect types microscopic defect evolution macroscopic crack propagation molecular dynamics simulation cohesive zone model

Working condition recognition of sucker rod pumping system based on 4-segment time-frequency signature matrix and deep learning

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Petroleum Science 2024年第1期21卷 641-653页

作者： Yun-Peng He Hai-bo Cheng Peng Zeng Chuan-Zhi Zang Qing-Wei Dong Guang-Xi wan.Xiao-Ting Dong State Key Laboratory of Robotics Shenyang Institute of AutomationChinese Academy of SciencesShenyang 110016LiaoningChina Key Laboratory of Networked Control Systems Chinese Academy of SciencesShenyang 110016LiaoningChina Institutes for Robotics and Intelligent Manufacturing Chinese Academy of SciencesShenyang 110169LiaoningChina University of Chinese Academy of Sciences Beijing100049China School of Artifcial Intelligence Shenyang University of TechnologyShenyang 110870LiaoningChina

High-precision and real-time diagnosis of sucker rod pumping system(SRPS)is important for quickly mastering oil well *** learning-based method for classifying the dynamometer card(DC)of oil wells is an efficient diagnosis ***,the input of the DC as a two-dimensional image into the deep learning framework suffers from low feature utilization and high computational ***,different SRPSs in an oil field have various system parameters,and the same SRPS generates different DCs at different ***,there is heterogeneity in field data,which can dramatically impair the diagnostic *** solve the above problems,a working condition recognition method based on 4-segment time-frequency signature matrix(4S-TFSM)and deep learning is presented in this ***,the 4-segment time-frequency signature(4S-TFS)method that can reduce the computing power requirements is proposed for feature extraction of DC ***,the 4S-TFSM is constructed by relative normalization and matrix calculation to synthesize the features of multiple data and solve the problem of data ***,a convolutional neural network(CNN),one of the deep learning frameworks,is used to determine the functioning conditions based on the *** on field data verify that the proposed diagnostic method based on 4S-TFSM and CNN(4S-TFSM-CNN)can significantly improve the accuracy of working condition recognition with lower computational *** the best of our knowledge,this is the first work to discuss the effect of data heterogeneity on the working condition recognition performance of SRPS.

关键词： Sucker-rod pumping system Dynamometer card Working condition recognition Deep learning Time-frequency signature Time-frequency signature matrix

Triple three-dimensional MS/MS spectrum facilitates quantitative ginsenosides-targeted sub-metabolome characterization in notoginseng

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Acta Pharmaceutica Sinica B 2024年第9期14卷 4045-4058页

作者： Ke Zhang Jinru Jia Ting Li Wenjing Liu Pengfei Tu Jian-bo wan.Jun Li Yuelin Song Modern Research Center for Traditional Chinese Medicine Beijing Research Institute of Chinese MedicineBeijing University of Chinese MedicineBeijing 100029China SCIEX China Beijing 100015China School of Pharmacy Henan University of Chinese MedicineZhengzhou 450046China State Key Laboratory of Quality Research in Chinese Medicine Institute of Chinese Medical SciencesUniversity of MacaoTaip1Macao 999078China

Although serving as the workhorse,MS/MS cannot fully satisfy the analytical requirements of quantitative sub-metabolome *** more information intrinsically correlates to more structural and concentration clues,here,efforts were devoted to comprehensively tracing and deciphering MS/MS behaviors through constructing triple three-dimensional(33D)-MS/MS ***-targeted metabolomics of notoginseng,one of the most famous edible medicinal plants,was employed as a *** authentic ginsenosides were deployed to build the correlations between 33D-MS/MS spectra and structure/concentration *** assaying ginsenosides with progressive concentrations using QTOF-MS to configure 1st 3D spectrum,the generations of MS1 spectral signals,particularly multi-charged multimer anions,e.g.,[2Me2H]2e and[2Mt2HCOO]2e ions,relied on both concentration and the amount of sugar *** programming progressive collision energies to the front collision cell of Qtrap-MS device to gain 2nd 3D spectrum,optimal collision energy(OCE)corresponding to the glycosidic bond fission was primarily correlated with the masses of precursor and fragment ions and partially governed by the glycosidation *** quantitative relationships between OCEs and masses of precursor and fragment ions were utilized to build large-scale quantitative program for *** applying progressive exciting energies to the back collision chamber to build 3rd 3D spectrum,the fragment ion and the decomposition product anion exhibited identical dissociation trajectories when they shared the same molecular *** ginsenosides-focused quantitative metabolomics,significant differences occurred for sub-metabolome amongst different parts of *** differential ginsenosides were confirmatively identified by applying the correlations between 33D-MS/MS spectra and ***,33D-MS/MS spectrum covers all MS/MS behaviors and dramatically faci

关键词： Quantitative submetabolome characterization Ginsenosides Structural identification Notoginseng Full exciting energy ramp-MS3 spectrum

Deciphering dynamic surface of PtRu alloy nanocatalysts to revisit their synergistic effects during the electrooxidation

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Science China Chemistry 2024年第7期67卷 2224-2233页

作者： Xiao-Chong Li bo wan. Zhou Yu Qiang wan.Ju-Fang Zheng Emmanuel Maisonhaute Xiao-Shun Zhou Ya-Hao wan. Key Laboratory of the Ministry of Education for Advanced Catalysis Materials Institute of Physical ChemistryZhejiang Normal UniversityJinhua 321004China Laboratoire Interface et Systèmes Electrochimiques CNRS UMR 8235Sorbonne UniversitéF-75252 Paris cedex 5France

Correlating dynamic structural transformation of catalysts with the surface intermediate species under operating conditions is critical for updating the understanding of structure–performance ***,we probe the electrochemical potentialdependent surface structures and adsorbed intermediates on PtRu binary alloy nanocatalysts to revisit its synergistic mechanisms for CO electrooxidation enhanced ***-situ spectral characteristics by using modified shell-isolated nanoparticle-enhanced Raman spectroscopy,show that in acidic solution,when the potential is positively scanned from 0.1 V to 1.5 V relative to reversible hydrogen electrode(RHE),the surface of the alloy catalyst evolves from metallic PtRu to adsorbed oxygen gradually covering and accumulating on Ru sites(denoted as PtRuO_(x),x≤2),forming segregated RuO_(2),and finally forming a threedimensional oxide layer(denoted as 3D PtRuO_(4)).Moreover,molecular evidence associated with periodic density functional theory calculations reveals that electronic effects promote ruthenium to become more oxidizable and *** particular,we found here that ^(*)O and ^(*)OH at surface RuO_(x) sites are highly efficient CO oxidation active species in comparison to the same entities adsorbed on metallic Ru *** work sheds light on the complex surface dynamic process of practical Pt-based binary nanocatalysts and improves the understanding of synergistic mechanism for the development of fuel cell devices.

关键词： in-situ Raman spectroscopy surface evolution bifunctional mechanism PtRu electrooxidation

Establishing cell suitability for high-level production of licorice triterpenoids in yeast

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Acta Pharmaceutica Sinica B 2024年第9期14卷 4134-4148页

作者： Wentao Sun Shengtong wan.Chuyan Liu Ruwen wan. Haocheng Zhang Lei Qin Runming wan. bo Lv Chun Li Department of Chemical Engineering Tsinghua UniversityBeijing 100084China Key Laboratory of Medical Molecule Science and Pharmaceutics Engineering Ministry of Industry and Information TechnologyInstitute of Biochemical EngineeringSchool of Chemistry and Chemical EngineeringBeijing Institute of TechnologyBeijing 100081China The University of Chicago ChicagoIL 60637USA Key Lab for Industrial Biocatalysis Ministry of EducationTsinghua UniversityBeijing 100084China Center for Synthetic and Systems Biology Tsinghua UniversityBeijing 100084China Institute of Biopharmaceutical and Health Engineering Tsinghua Shenzhen International Graduate SchoolTsinghua UniversityShenzhen 518055China

Yeast has been an indispensable host for synthesizing complex plant-derived naturalcompounds, yet the yields remained largely constrained. This limitation mainly arises from overlookingthe importance of cell and pathway suitability during the optimization of enzymes and pathways. Herein,beyond conventional enzyme engineering, we dissected metabolic suitability with a framework forsimultaneously augmenting cofactors and carbon flux to enhance the biosynthesis of heterogenoustriterpenoids. We further developed phospholipid microenvironment engineering strategies, dramaticallyimproving yeast’s suitability for the high performance of endoplasmic reticulum (ER)-localized, ratelimitingplant P450s. Combining metabolic and microenvironment suitability by manipulating only threegenes, NHMGR (NADH-dependent HMG-CoA reductase), SIP4 (a DNA-binding transcription factor)andGPP1 (Glycerol-1-phosphate phosphohydrolase 1), we enabled the high-level production of 4.92 g/L rarelicorice triterpenoids derived from consecutive oxidation of b-amyrin by two P450 enzymes afterfermentation optimization. This production holds substantial commercial value, highlighting the criticalrole of establishing cell suitability in enhancing triterpenoid biosynthesis and offering a versatileframework applicable to various plant natural product biosynthetic pathways.

关键词： Cell suitability Phospholipid microenvironment Cytochrome P450 Triterpenoids Saccharomyces cerevisiae