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DYNAMICAL ANALYSIS OF AN AGE-STRUCTURED TUBERCULOSIS MODEL DRIVEN BY THE NOVEL M72/AS01EVACCINE IN CONTAMINATED ENVIRONMENTS 认领 引用
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作者 Qian JIANG Zhijun LIU Lianwen WANG 《Acta Mathematica Scientia》 SCIE CSCD 2026年第1期330-360,共31页
To assess the effectiveness of vaccination in contaminated environments,this study introduces a modeling framework that encompasses two transmission routes,namely direct human-to-human contact and indirect human-to-en... To assess the effectiveness of vaccination in contaminated environments,this study introduces a modeling framework that encompasses two transmission routes,namely direct human-to-human contact and indirect human-to-environment contact,as well as the implementation of new M72/AS01Evaccine.Motivated by this,a coupled age-structured tuberculosis(TB)model is proposed.Its well-posedness requirement is verified using the integrated semigroup theory.Furthermore,this study presents a comprehensive analysis of threshold dynamics associated with the proposed model.Specifically,the global stability of the disease-free and positive steady states is demonstrated by employing Lyapunov functionals.Lastly,the effects of the vaccination with M72/AS01Eand contaminated environments on TB control are numerically simulated.Experimental results indicate that high concentrations of Mycobacterium tuberculosis in contaminated environments may somewhat impede TB control efforts,but that large-scale deployment of new vaccine could significantly reduce the prevalence of TB. 展开更多
关键词 tuberculosis model age structure contaminated environments M72/AS01EvaccinE stability
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Emergence of Lineage E.4 and Structural Plasticity of A28L Protein in Mpox Virus:Characterization of LCR7 Length Polymorphisms Across Lineages—Shenzhen City,Guangdong Province,China,2023–2025 认领 引用
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作者 Bo Peng Ziquan Lyu +7 位作者 Wenxiao Gong Xiaomin Zhang Shiting Chen Wenjuan Ma Xiaolu Shi Jia Wan Jing Qu Xiaoping Dong 《China CDC weekly》 SCIE CSCD 2026年第27期847-851,共5页
Introduction:A28L,a virion membrane protein involved in mpox virus(MPXV)attachment and fusion,is a major target of neutralizing antibodies and a hotspot for genetic variation.This study investigated variations in its ... Introduction:A28L,a virion membrane protein involved in mpox virus(MPXV)attachment and fusion,is a major target of neutralizing antibodies and a hotspot for genetic variation.This study investigated variations in its low-complexity region(LCR7)among MPXV strains circulating in Shenzhen,China.Methods:A total of 6,834 publicly available MPXV clade IIb genomes from the Global Initiative on Sharing All Influenza Data(GISAID)were analyzed,and whole-genome sequencing was performed on 260 clinical isolates collected in Shenzhen during 2023–2025.LCR7 polymorphisms in OPG153/A28L and associated amino acid substitutions were characterized.Results:Global genomic analysis identified a conserved four-residue deletion(D382–D385)in LCR7 that was prevalent in lineage A viruses.In contrast,the dominant B.1 lineage and its derivatives,including all Shenzhen isolates,exhibited heterogeneous truncations,most commonly a single D385 deletion.Among locally circulating E.4 viruses,complex deletion patterns(e.g.,D383–D385 and D384–D385)and a characteristic amino acid substitution,OPG153_E293Q,were identified,the latter representing a lineage-defining mutation.Conclusion:MPXV evolution in Shenzhen was characterized by LCR7 structural plasticity and the accumulation of lineage-specific amino acid substitutions,supporting the genomic accordion model of viral adaptation.Continued surveillance of these genomic features is essential for monitoring local transmission and informing public health interventions. 展开更多
关键词 clinical isolates collected lineage E virion membrane protein mpox virus mpxv attachment LCR length polymorphisms MPXV neutralizing antibodies structural plasticity
Allozyme Diversity and Population Genetic Structure of Three Medicinal Epimedium Species from Hubei 认领 引用 被引量：8
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作者 Yanqin Xu Zuozhou Li +1 位作者 Ying Wang Hongwen Huang 《Journal of Genetics and Genomics》 CAS 北大核心 2007年第1期56-71,共16页
Three Epimedium species,E.pubescens Maxim.,E.sagittatum(Sieb.&Zucc.)Maxim.,and E.wushanense T.S.Ying,which are sympatrically distributed in the western Hubei Province,have been used in traditional Chinese medicine... Three Epimedium species,E.pubescens Maxim.,E.sagittatum(Sieb.&Zucc.)Maxim.,and E.wushanense T.S.Ying,which are sympatrically distributed in the western Hubei Province,have been used in traditional Chinese medicine(TCM)for about 2,000 years.Genetic variability and population genetic structure of 11 natural populations of these Epimedium species were investigated using isoelectric focusing in thin-layer polyacrylamide slab gels.Of the 22 enzyme systems prescreened,six coding for 13 loci and 45 alleles were resolved,which were used for analyzing genetic diversity and population structure at both intraspecific and interspecific levels.The results showed that:l)high levels of genetic diversity were observed in all three species(A=2.6-3.2,P=69.2%-84.6%,Ho=0.274-0.377,HE=0.282-0.369),which were higher than that of other herbaceous and aulmal-pollinated species with similar life-history characteristics;2)there was significant deviation from Hardy-Weinberg Equilibrium,with one half of the loci showing heterozygote excess and the other homozygote excess,in all populations,suggesting the complicated breeding system of Epimedium species;3)the low level of intraspecific and interspecific genetic differentiation(GST=0.0246-0.0409 and 0.0495-0.1213,respectively)indicated a high level of gene flow among populations and close genetic relationship among the three species;and 4)UPGMA cluster analysis further showed that E.pubescens was more closely related to E.sagittatum than to E.wushanense,which was in good agreement with the morphological characters and the recent phylogenetic analysis of these species.On the basis of these results,it was concluded that the mixed breeding system,long-lived perennial life form,ancient evolutionary history,and seed dispersal by ants in Epimedium are responsible for the genetic variation and population structure of these species. 展开更多
关键词 EpimEdium pubescens Maxim. E.sagittatum(SiEb.&Zucc.)Maxim. E.wushanEnsE T.S.Ying allozyme genetic diversity population structure
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Nonlinearity Modulating Intensities and Spatial Structures of Central Pacific and Eastern Pacific El Nio Events 认领 引用 被引量：2
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作者 Wansuo DUAN Chaoming HUANG Hui XU 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2017年第6期737-756,共20页
This paper compares data from linearized and nonlinear Zebiak-Cane model, as constrained by observed sea surface temperature anomaly （SSTA）, in simulating central Pacific （CP） and eastern Pacific （EP） E1 Nino. T... This paper compares data from linearized and nonlinear Zebiak-Cane model, as constrained by observed sea surface temperature anomaly （SSTA）, in simulating central Pacific （CP） and eastern Pacific （EP） E1 Nino. The difference between the temperature advections （determined by subtracting those of the linearized model from those of the nonlinear model）, referred to here as the nonlinearly induced temperature advection change （NTA）, is analyzed. The results demonstrate that the NTA records warming in the central equatorial Pacific during CP E1 Nino and makes fewer contributions to the structural distinctions of the CP E1 Nino, whereas it records warming in the eastern equatorial Pacific during EP E1 Nino, and thus significantly promotes EP E1 Nino during E1 Nino-type selection. The NTA for CP and EP E1 Nino varies in its amplitude, and is smaller in CP E1 Nino than it is in EP E1 Nino. These results demonstrate that CP E1 Nino are weakly modulated by small intensities of NTA, and may be controlled by weak nonlinearity; whereas, EP E1 Nino are significantly enhanced by large amplitudes of NTA, and are therefore likely to be modulated by relatively strong nonlinearity. These data could explain why CP E1 Nino are weaker than EP E1 Nino. Because the NTA for CP and EP E1 Nino differs in spatial structures and intensities, as well as their roles within different E1 Nino modes, the diversity of E1 Nino may be closely related to changes in the nonlinear characteristics of the tropical Pacific. 展开更多
关键词 E1 Nifio diversity nonlinearity intensity spatial structures nonlinear temperature advection
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Disbond detection with piezoelectric wafer active sensors in RC structures strengthened with FRP composite overlays 认领 引用 被引量：3
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作者 Victor Giurgiutiu Kent Harries +2 位作者 Michael Petrou Joel Bost Josh B.Quattlebaum 《Earthquake Engineering and Engineering Vibration》 EI 2003年第2期213-223,共11页
The capability of embedded piezoelectric wafer active sensors(PWAS)to perform in-situ nondestructive evaluation(NDE)for structural health monitoring(SHM)of reinforced concrete(RC)structures strengthened with fiber rei... The capability of embedded piezoelectric wafer active sensors(PWAS)to perform in-situ nondestructive evaluation(NDE)for structural health monitoring(SHM)of reinforced concrete(RC)structures strengthened with fiber reinforced polymer(FRP)composite overlays is explored.First,the disbond detection method were developed on coupon specimens consisting of concrete blocks covered with an FRP composite layer.It was found that the presence of a disbond crack drastically changes the electromecfianical(E/M)impedance spectrum lneasurcd at the PWAS terlninals.The spectral changes depend on the distance between the PWAS and the crack tip.Second,large scale experiments were conducted on a RC beam strengthened with carbon fiber reinforced polymer(CFRP)composite overlay.The beam was subject to an accelerated fatigue load regime in a three-point bending configuration up to a total of 807,415 cycles.During these fatigue tests,the CFRP overlay experienced disbonding beginning at about 500,000 cycles.The PWAS were able to detect the disbonding before it could be reliably seen by visual inspection.Good correlation between the PWAS readings and the position and extent of disbond damage was observed.These preliminary results demonstrate the potential of PWAS technology for SHM of RC structures strengthened with FRP composite overlays. 展开更多
关键词 FRP composite overlays composite strengthening and rehabilitation structural health monitoring piezoelectric wafer active sensors E/M impedance aging infrastructure disbond damage PWAS
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First-principles study on the electronic structure of Pb10−xCux(PO4)6O(x=0,1) 认领 引用 被引量：1
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作者 Junwen Lai Jiangxu Li +2 位作者 Peitao Liu Yan Sun Xing-Qiu Chen 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2024年第4期66-70,共5页
Recently,Lee et al.claimed the experimental discovery of room-temperature ambient-pressure super-conductivity in a Cu-doped lead-apatite(LK-99)(arXiv:2307.12008,arXiv:2307.12037).Remarkably,the claimed superconductivi... Recently,Lee et al.claimed the experimental discovery of room-temperature ambient-pressure super-conductivity in a Cu-doped lead-apatite(LK-99)(arXiv:2307.12008,arXiv:2307.12037).Remarkably,the claimed superconductivity can persist up to 400 K at ambient pressure.Despite the experimental im-plication,the electronic structure of LK-99 has not yet been studied.Here,we investigate the electronic structures of LK-99 and its parent compound using first-principles calculations,aiming to elucidate the doping effects of Cu.Our results reveal that the parent compound Pb10(PO4)6O is an insulator,while Cu doping induces an insulator-metal transition and thus volume contraction.The band structures of LK-99 around the Fermi level are featured by a half-filled flat band and a fully-occupied flat band.These two very flat bands arise from both the 2p orbitals of 1/4-occupied O atoms and the hybridization of the 3d orbitals of Cu with the 2p orbitals of its nearest-neighboring O atoms.Interestingly,we observe four van Hove singularities on these two flat bands.Furthermore,we show that the flat band structures can be tuned by including electronic correlation effects or by doping different elements.We find that among the considered doping elements(Ni,Cu,Zn,Ag,and Au),both Ni and Zn doping result in the gap opening,whereas Au exhibits doping effects more similar to Cu than Ag.Our work establishes a foundation for fu-ture studies to investigate the role of unique electronic structures of LK-99 in its claimed superconducting properties. 展开更多
关键词 First-principles calculations Density functional theory ElEctronic structur e Superconductivity Flat bands Strongly correlated electrons
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Synthesis, Crystal Structure and Antitumor Activity of (E)-4-tert-Butyl-N-(2,4-dichlorobenzylidene)-5-(1,2,4-triazol-1-yl)-thiazol-2-amine 认领 引用 被引量：5
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作者 胡艾希 覃智 +1 位作者 叶姣 夏曙 《Chinese Journal of Structural Chemistry》 SCIE CAS 2010年第11期1680-1683,共4页
The title compound （E）-4-tert-butyl-N-（2,4-dichlorobenzylidene）-5-（1,2,4-triazol-1-yl）-thiazol-2-amine was synthesized by the reaction of 4-tert-butyl-5-（1,2,4-triazol-1-yl）-thiazol-2-amine with 2,4-dichlorobe... The title compound （E）-4-tert-butyl-N-（2,4-dichlorobenzylidene）-5-（1,2,4-triazol-1-yl）-thiazol-2-amine was synthesized by the reaction of 4-tert-butyl-5-（1,2,4-triazol-1-yl）-thiazol-2-amine with 2,4-dichlorobenzaldehyde, and its crystal structure was determined by singlecrystal X-ray diffraction. The crystal belongs to the triclinic system, space group P1 with a = 7.9748（4）, b = 10.1803（5）, c = 11.4603（6）, α = 102.882（1）, β = 100.253（1）, γ = 104.457（1）°, V = 850.95（7）3, Z = 2, F（000） = 392, C16H15Cl2N5S, Mr = 380.29, Dc = 1.484 g/cm3, S = 1.095, μ = 0.512 mm-1, the final R = 0.0301 and wR = 0.0965 for 3334 observed reflections （I 〉 2σ（I））. The preliminary antitumor activity shows that for the title compound the IC50 of Hela is 0.175 μmol/mL and that of Bel7402 is 0.156 μmol/mL. 展开更多
关键词 （E）-4-tErt-butyl-N-（2,4-dichorobEnzylidEnE）-5-（1,2,4-triazl-1-yl）-thiazol-2-aminE,crystal structure synthesis antitumor activity
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Synthesis,Crystal Structure and Fungicidal Activity of(E)-2-[(4-tert-Butyl-5-(4-methoxybenzyl)thiazol-2-ylimino)methyl]phenol 认领 引用 被引量：2
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作者 胡艾希 曹高 +2 位作者 马颍绮 张建宇 欧晓明 《Chinese Journal of Structural Chemistry》 SCIE CAS 北大核心 2008年第10期1235-1239,共5页
The title compound （E）-2-[（4-tert-butyl-5-（4-methoxybenzyl）thiazol-2-ylimino）methyl]phenol was synthesized by the reaction of 5-（4-methoxybenzyl）-4-tert- butylthiazol-2-amine with salicylaldehyde, and its crys... The title compound （E）-2-[（4-tert-butyl-5-（4-methoxybenzyl）thiazol-2-ylimino）methyl]phenol was synthesized by the reaction of 5-（4-methoxybenzyl）-4-tert- butylthiazol-2-amine with salicylaldehyde, and its crystal structure was determined by single-crystal X-ray diffraction. The crystal belongs to the monoclinic system, space group P21/c with a = 5.9362（8）, b = 11.5070（15）, c = 29.460（4）A, β= 97.326（3）°, V = 1995.9（5） A^3, Z = 4, F（000） = 808, C22H24N2O2S, Mr= 380.49, De= 1.266 g/cm^3, S = 1.031,μ = 0.181 mm^-1, the final R = 0.0474 and wR = 0.1441 for 4327 observed reflections （I 〉 2σ（I））. Intramolecular O-H…N hydrogen bond is observed in the crystal. The preliminary bioassay showed that the title compound exhibits 95% inhibition rate against Rhizoctonia solani at the test concentration of 500 mg/L. 展开更多
关键词 crystal structure synthesis fungicidal activity （E）-2- [（4-tert-butyl-5-（4-methoxybenzyl）thiazol-2-ylimino）methyl]phenol
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Critical Behavior in Nuclear Structure from Spherical toγ-Soft Deformed Shape in IBM 认领 引用 被引量：3
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作者 ZHANG Jin-Fu LU Li-Jun BAI Hong-Bo 《Communications in Theoretical Physics》 SCIE CAS 2007年第4期705-710,共6页
Comparing with the predictions of the transitional dynamical symmetry E(5)proposed by Iachello[Phys.Rev.Lett.85(2000)3580],the critical behaviors from U(5)-0(6)are studied in the space of two control parameters in the... Comparing with the predictions of the transitional dynamical symmetry E(5)proposed by Iachello[Phys.Rev.Lett.85(2000)3580],the critical behaviors from U(5)-0(6)are studied in the space of two control parameters in the interacting boson model.A simple shape phase diagram has been presented.It is found that E(5)predictions cannot be exactly reproduced by our calculations and that the best agreement is close to the calculations with boson number N=9.By comparing with experimental data on E(5)-like nuclei,we find that E(5)predictions and IBM calculations can reproduce the energy ratios and E2 transition ones. 展开更多
关键词 nuclear structure critical behavior E(5)nuclEi IBM
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Synthesis and Crystal Structure of Tert-butyl 4-[(E)-4-(1,3-Dioxo-1,3-dihydro-2H-isoindol-2-yl)-1-butenyl] Benzoate 认领 引用
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作者 张新歌 张慧杰 +1 位作者 王瑱 李朝兴 《Chinese Journal of Structural Chemistry》 SCIE CAS 北大核心 2006年第3期300-304,共5页
The title compound tert-butyl 4-[（E）-4-（1,3-dioxo-1,3-dihydro-2H-isoindol-2-yl）- 1-butenyl] benzoate has been synthesized and characterized by X-ray crystallography. It crystallizes in monoclinic, space group C2/c... The title compound tert-butyl 4-[（E）-4-（1,3-dioxo-1,3-dihydro-2H-isoindol-2-yl）- 1-butenyl] benzoate has been synthesized and characterized by X-ray crystallography. It crystallizes in monoclinic, space group C2/c with a = 14.875（3）, b = 8.9796（13）, c = 34.736（6） A°, β = 95.981（4）°, V= 4614.4（14）A°^3, Z= 8, Dc = 1.213 g/cm^3, F（000） = 1792,μ（MoKα） = 0.084 mm^-1, R = 0.0602 and wR = 0.1445 for 4613 unique reflections with 2272 observed ones （I〉 2σ（I））. The results of crystal structure determination show that the title compound has a layer structure, and the two benzene rings in molecule are parallel to each other. 展开更多
关键词 tert-butyl 4-[（E）-4-（1,3-dioxo-1,3-dihydro-2H-isoindol-2-yl）-1-butEnyl]bEnzoatE synthesis crystal structure
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Horizontal structure of convergent wind shear associated with sporadic E layers over East Asia 认领 引用 被引量：2
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作者 LiHui Qiu Xian Lu +8 位作者 Tao Yu Yosuke Yamazaki HuiXin Liu Yang-Yi Sun HaoNan Wu XiaoMin Zuo XiangXiang Yan Yan Yu YiFan Qi 《Earth and Planetary Physics》 CAS CSCD 2023年第5期548-557,共10页
At present,the main detection instruments for observing sporadic E(Es)layers are ground-based radars,dense networks of ground-based global navigation satellite system(GNSS)receivers,and GNSS radio occultation,but they... At present,the main detection instruments for observing sporadic E(Es)layers are ground-based radars,dense networks of ground-based global navigation satellite system(GNSS)receivers,and GNSS radio occultation,but they cannot capture the whole picture of the horizontal structure of Es layers.This study employs the Whole Atmosphere Community Climate Model with thermosphere and ionosphere eXtension model(WACCM-X 2.1)to derive the horizontal structure of the ion convergence region(HSICR)to explore the shapes of the large-scale Es layers over East Asia for the period from June 1 to August 31,2008.The simulation produced the various shapes of the HSICRs elongated in the northwest-southeast,northeast-southwest,or composed of individual small patches.The close connection between Es layer critical frequency(foEs)and vertical ion convergence indicates that the HSICR is a good candidate for revealing and explaining the horizontal structure of the large-scale Es layers. 展开更多
关键词 sporadic E layer horizontal structure wind shear WACCM-X model
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基于Pro/EMechanica Structure的塑料产品装配结构设计 认领 引用 被引量：1
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作者 董海东 杨延波 《工程塑料应用》 CAS 北大核心 2010年第9期37-41,共5页
以手机的装配结构设计为例,在分析其零部件的结构特点及卡扣连接、压力装配等装配关系后,借助Pro/E Mechanica Structure模块分析手机在装配中,手机前盖、后盖等塑料零部件在静载荷作用下可能出现的变形,进而改进并优化结构,并且对改进... 以手机的装配结构设计为例,在分析其零部件的结构特点及卡扣连接、压力装配等装配关系后,借助Pro/E Mechanica Structure模块分析手机在装配中,手机前盖、后盖等塑料零部件在静载荷作用下可能出现的变形,进而改进并优化结构,并且对改进前后结构受静载荷作用的应力值进行比较,结果满足使用的力学性能要求。因此通过基于Pro/E Mechanica Structure的塑料产品装配设计,可以降低成本、加快完成塑料产品的开发。 展开更多
关键词 塑料产品 结构 优化 Pro/E Mechanica Structure 力学性能
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基于Pro/E MECHANICA Structure的塑件结构优化 认领 引用 被引量：1
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作者 董海东 葛正浩 董青青 《广西工学院学报》 2010年第2期28-31,共4页
为使手机在装配时,前盖、后盖等塑料零件受静载荷作用下不变形损坏,在熟悉其装配关系基础上,借助Pro/EMECHANICA Structure对手机在装配过程中进行静力分析,并对主要零件的结构进行修改和优化,使其满足使用力学性能要求,使得手机前后盖... 为使手机在装配时,前盖、后盖等塑料零件受静载荷作用下不变形损坏,在熟悉其装配关系基础上,借助Pro/EMECHANICA Structure对手机在装配过程中进行静力分析,并对主要零件的结构进行修改和优化,使其满足使用力学性能要求,使得手机前后盖及电池盖能顺利组装而不会损坏. 展开更多
关键词 结构 优化 Pro/E MECHANICA Structure 力学性能
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Synthesis and Structure of N-(E)-Enoyl(-)-bornane-10,2-sultams 认领 引用
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作者 LI Yan CHEN Liao rong +1 位作者 ZHOU Zhong qiang HUANG Jin xia 《Chemical Research in Chinese Universities》 SCIE EI CAS 2001年第1期56-62,共7页
Two potential chiral auxiliaries, N (E ) enoyl(-) bornane 10,2 sultams, were synthesized from (-) bornane 10,2 sultams. The molecular crystal structures of the title compounds were determined by diffraction analysis. ... Two potential chiral auxiliaries, N (E ) enoyl(-) bornane 10,2 sultams, were synthesized from (-) bornane 10,2 sultams. The molecular crystal structures of the title compounds were determined by diffraction analysis. The crystal of C 16 O 3SNH 25 belongs to a rhombic system, the space group is P 2 12 12 1 with cell parameters: a =0 734 6(7) nm, b =1 142 7(3) nm, c =2 009 7(3) nm, β =90 00°, V =1 686 9 nm 3, Z=4, D c=1 250 g/cm 3, μ =1 926 cm -1 and F (000)=672. The crystal of C 15 O 3SNH 23 belongs to a rhombic system, the space group is P 2 12 12 1 with cell parameters: a =0 738 2(2) nm, b =0 921 6(1) nm, c =2 280 9(8) nm, β =90 00°, V =1 551 7 nm 3, Z =4, D c=1 273 g/cm 3, μ =2 504 cm -1 and F (000)=640. The structural characteristics with respect to the potential utility for the stereoselective Michael addition reaction of the N enoyl group are discussed. 展开更多
关键词 N (E ) Enoyl(-) bornane 10 2 sultam Crystal structure Michael addition
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Synthesis and Crystal Structure of(2E,6E)-2,6-bis(2,3-dimethoxybenzylidene)cyclohexanone 认领 引用
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作者 张丽 汪洪 +6 位作者 赵承光 唐琴琴 熊伟 蔡跃飘 陈高帜 胡杰 梁广 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2011年第2期278-283,共6页
The new title compound （2E,6E）-2,6-bis（2,3-dimethoxybenzylidene）cyclohexanone （C 24 H 26 O 5,M r=394.45） has been synthesized,and its crystal structure was studied.The title compound crystallizes in the orthorho... The new title compound （2E,6E）-2,6-bis（2,3-dimethoxybenzylidene）cyclohexanone （C 24 H 26 O 5,M r=394.45） has been synthesized,and its crystal structure was studied.The title compound crystallizes in the orthorhombic system,space group Pca2 1 with a=17.536（2）,b=14.8515（16）,c=8.0512（9）,V=2096.8（4） 3,Z=4,D c=1.250 g/cm 3,λ=0.71073,μ=0.087 mm-1 and F（000）=840.The structure was solved by direct methods and refined to R=0.0533 and wR=0.1248 from 2727 observed reflections （I 2σ（Ⅰ））.The title molecules are connected through hydrogen bonds to generate a 3-D supramolecule.The preliminary biological tests showed definitely biological activity for the title compound. 展开更多
关键词 （2E 6E）-2 6-bis（2 3-dimethoxybenzylidene）cyclohexanone synthesis crystal structure
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Synthesis,Crystal Structure and Antitumor Activity of(E)-N-(4-Fluorobenzylidene)-3-(methylthio)-5-(3,4,5-trimethoxyphenyl)-4H-1,2,4-triazol-4-amine 认领 引用
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作者 LIN Wei-Yuan YANG Fang +2 位作者 DUAN An-Na YOU Wen-Wei ZHAO Pei-Liang 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2018年第10期1557-1562,共6页
The crystal structure of the title compound（E）-N-（4-fluorobenzylidene）-3-（methylthio）-5-（3,4,5-trimethoxyphenyl）-4 H-1,2,4-triazol-4-amine（C_（19）H_（19）FN_4O_3S,Mr = 402.44） was synthesized,and its struct... The crystal structure of the title compound（E）-N-（4-fluorobenzylidene）-3-（methylthio）-5-（3,4,5-trimethoxyphenyl）-4 H-1,2,4-triazol-4-amine（C_（19）H_（19）FN_4O_3S,Mr = 402.44） was synthesized,and its structure was characterized by 1 H-NMR,13 C-NMR,ESI-MS and single-crystal X-ray diffraction.The crystal belongs to the triclinic system,space group P1 with a = 9.228（13）,b = 10.364（14）,c = 10.641（14） ？,α = 85.323（3）,β = 75.172（2）,γ = 80.903（3）°,μ = 0.20 mm^（-1）,M_r = 402.44,V = 970.64（10） ？~3,Z = 2,D_c = 1.377 g/cm^3,F（000） = 420,R = 0.0484 and wR = 0.1474 for 3181 observed reflections with I 〉 2σ（I）.In addition,the preliminary bioassay indicated that the title compound 5 exhibits better inhibitory activity against Hela than 5-fluorouracil. 展开更多
关键词 （E）-N-（4-fluorobEnzylidEnE）-3-（mEthylthio）-5-（3,4,5-trimEthoxyphEnyl）-4H-1,2,4-triazol-4-aminE synthesis crystal structure anfitumor activity
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Synthesis,Crystal Structure and DNA-binding Properties of a New Copper(Ⅱ) Schiff Base Complex 认领 引用 被引量：1
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作者 秦蓓 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2012年第8期1187-1193,共7页
A new asymmetric bidentate copper（Ⅱ） complex,CuL 2（HL=2-（（E）-（4-bromophenylimino）methyl）-6-bromo-4-chlorophenol）,has been synthesized and characterized by elemental analyses and single-crystal X-ray diffrac... A new asymmetric bidentate copper（Ⅱ） complex,CuL 2（HL=2-（（E）-（4-bromophenylimino）methyl）-6-bromo-4-chlorophenol）,has been synthesized and characterized by elemental analyses and single-crystal X-ray diffraction.The complex crystallizes in the monoclinic space group P2 1 /c with a=11.218（3）,b=9.355（3）,c=13.449（4）,β=108.722（4）°,V=1336.8（6）3,Z=2,Dc=2.008 g/cm 3,μ（MoKα）=7.024 mm-1,F（000）=806,S=0.999,the final R=0.0342 and wR=0.0641for2611observed reflections （I〉2σ（I））.The central copper（Ⅱ） is four-coordinate and bonds to two nitrogen and two oxygen atoms from two Schiff base ligands.The complex is linked into a two-dimensional supramolecular structure by weak intermolecular interactions.In addition,DNA-binding properties of the metal complex were investigated using spectrometric titrations and viscosity measurements.The results show that the complex binds with calf-thymus DNA（CT-DNA）,presumably via a partial intercalative mode.The intrinsic binding constant of the Cu（Ⅱ） complex with DNA is 7.335×10 3 M-1. 展开更多
关键词 crystal structure 2-（（E）-（4-bromophEnylimino）mEthyl）-6-bromo-4-chlorophEnol copper（Ⅱ） complex calf-thymus DNA partial intercalative mode
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Synthesis, Crystal Structure and Antitumor Activity of (E)-1-(7-Methoxy-2,2-dimethyl-2,3-dihydrobenzofuran-5- yl)-3-(2-methoxyphenyl)-2-(1H-1,2,4-triazol-1-yl)propenol 认领 引用
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作者 李水师 李婉 +1 位作者 叶姣 胡艾希 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2017年第7期1142-1146,共5页
The title compound, （E）-1-（7-methoxy-2,2-dimethyl-2,3-dihydrobenzofuran-5-yl）- 3-（2-methoxyphenyl）-2-（1H-1,2,4-triazol-1-yl）propenol （3a）, was synthesized by the Aldol con- densation reaction of 1-（7-methox... The title compound, （E）-1-（7-methoxy-2,2-dimethyl-2,3-dihydrobenzofuran-5-yl）- 3-（2-methoxyphenyl）-2-（1H-1,2,4-triazol-1-yl）propenol （3a）, was synthesized by the Aldol con- densation reaction of 1-（7-methoxy-2,2-dimethyl-2,3-dihydrobenzofuran-5-yl）-2-（1,2,4-triazol- 1-yl）ethanone with 2-methoxybenzaldehyde and then reduced with NaBH4, and its crystal structure was determined by single-crystal X-ray diffraction： monoclinic system, space group P21 with a = 6.2002（3）, b = 12.8452（7）, c = 13.2257（7） ？, Z = 2, V = 1031.23（9） ？3, Mr = 407.46, Dc = 1.312 Mg/m3, S = 1.054, μ = 0.091 mm-1, F（000） = 432, the final R = 0.0353 and wR = 0.0769 for 3161 observed reflections （I 〉 2σ（I））. X-ray analysis displays that the title compound adopts an E configuration for the C（7）=C（8） double bond and S configuration for the chirality center with the specific rotation of –63.75°. Furthermore, the stability of the crystal was maintained through the intermolecular hydrogen bond O（1）–H？？？N（3）. The antitumor assay exhibits that the title compound 3a （E configuration） has a good antitumor activity against the Hela cell line with the IC50 value of 36.9 μM, which is better than that of 3b （Z configuration）. 展开更多
关键词 （E）-1-（7-mEthoxy-2 2-dimethyl-2 3-dihydrobenzofuran-5-yl）-3-（2-methoxyphenyl）-2-（1H-1 2 4-triazol-1-yl）propenol synthesis crystal structure antitumor activity
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基于Tree-LSTM的表单控件推荐模型 认领 引用
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作者 罗俊辉 张钧波 潘哲逸 《计算机应用》 CSCD 北大核心 2026年第4期1115-1123,共9页
通过将表单中的控件与城市知识体系相关联,基于表单填报的数据能自动成为标准规范的城市知识图谱,这是解决数据要素规模化生产难题的新思路。然而,表单系统中内置的众多的以实体、关系及其属性的业务术语命名的控件使得用户难以快速找... 通过将表单中的控件与城市知识体系相关联,基于表单填报的数据能自动成为标准规范的城市知识图谱,这是解决数据要素规模化生产难题的新思路。然而,表单系统中内置的众多的以实体、关系及其属性的业务术语命名的控件使得用户难以快速找到所需控件,进而催生了表单控件推荐这一全新任务。针对表单应用场景差异大、配置上下文依赖复杂和表单配置数据稀疏这3个挑战,提出一种基于树形长短期记忆(Tree-LSTM)网络的表单控件推荐模型(TRFW)。首先,从丰富的通用表单配置数据中训练场景多分类模型,学习表单文本与场景特征之间的依赖关系;其次,使用基于Tree-LSTM的网络结构,捕捉表单上下文中的结构与主题特征,并基于此构造用户的配置意图特征;同时,训练基于自编码器(AE)的控件命名编码器,建立相似控件命名之间的松耦合连接关系,使得模型能够在推荐相似语义控件的同时,对新增控件具有良好的鲁棒性。在公开数据构建的数据集上的实验结果表明,所提模型与所有基准模型相比具有最优性能,HitRatio@1为84.62%,HitRatio@10为97.31%,与无监督的推荐方法相比,HitRatio@1至少提升了87.0%,与基于图卷积的推荐方法相比,HitRatio@1和HitRatio@10分别至少提升了32.4%与12.4%。可见,所提模型能够有效推荐出符合用户意图的控件列表,从而降低用户在选择控件时的交互成本。 展开更多
关键词 意图感知 树形长短期记忆网络 推荐模型 电子表单 城市知识体系
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Factor-structure of economic growth in E-commerce 认领 引用
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作者 吴隽 刘洪久 栾天行 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2003年第2期137-140,共4页
In order to analyze the factors having effect on economic growth of E commerce, the economic growth process of E commerce is divided into three stages; growth stage, stabilization stage and re growth stage. These thre... In order to analyze the factors having effect on economic growth of E commerce, the economic growth process of E commerce is divided into three stages; growth stage, stabilization stage and re growth stage. These three different stages are analysed using several economic growth theories, a set of factor structure is proposed for each stage of the economic growth process of E commerce. 展开更多
关键词 E commerce economy of E commerce factor structure
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