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Image retrieval based on color features integrated with anisotropic directionality

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Journal of Systems Engineering and Electronics 2010年第1期21卷 127-133页

作者： jing bai Xiaohua Wang Licheng Jiao Key Laboratory of Intelligent Perception and Image Understanding of Ministry of Education of China Institute of Intelligent Information Processing Xidian University Xi'an 710071 P. R. China

A novel image retrieval approach based on color features and anisotropic directional information is proposed for content based image retrieval systems （CBIR）. The color feature is described by the color histogram （CH）, which is translation and rotation invariant. However, the CH does not contain spatial information which is very important for the image retrieval. To overcome this shortcoming, the subband energy of the lifting directionlet transform （L-DT） is proposed to describe the directional information, in which L-DT is characterized by multi-direction and anisotropic basis functions compared with the wavelet transform. A global similarity measure is designed to implement the fusion of both color feature and anisotropic directionality for the retrieval process. The retrieval experiments using a set of COREL images demonstrate that the higher query precision and better visual effect can be achieved.

关键词： image retrieval color histogram directionlet transform anisotropic similarity.

Ring-opening metathesis polymerization of cyclopropene derivatives towards polyolefin elastomer analogues

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Science China Chemistry 2022年第11期65卷 2182-2187页

作者： jing bai Yu Wang Wei You Beijing National Laboratory for Molecular Sciences(BNLMS) CAS Key Laboratory of Engineering PlasticsInstitute of ChemistryChinese Academy of SciencesBeijing100190China University of Chinese Academy of Sciences Beijing 100049China

Polyolefin elastomers(POEs) are important reprocessable industrial materials with high strain-recovery performance. Traditional POEs are prepared from transition-metal-catalyzed polymerization of ethylene and α-olefins, while because of the complicated coordination polymerization mechanism, defining the actual distribution and length of alkyl branches in POEs is extremely challenging. We herein propose an alternative approach of synthesizing POE analogues from ring-opening metathesis polymerization(ROMP) of highly strained 3,3-alkyl-substituted cyclopropenes(CPEs). The structures of monomers and the substituents of Ru-catalysts are investigated in detail to evaluate the homobenzyl-substituted CPE derivative as a new living ROMP monomer. After copolymerization with cyclooctene and backbone hydrogenation, POE analogues with well-defined alkyl branches are prepared. Since the ROMP reactions have little isomerization and can also give good control of molecular weight and copolymer composition, it is hypothesized that this synthetic approach provides a novel platform to assist understanding the influence of branches on the properties of POEs.

关键词： cyclopropenes ring-opening metathesis polymerization polyolefin elastomers alkyl substituents

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lncRNA-TNFRSF13C调控miR-1246对牙周细胞低氧诱导因子1α的作用

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中国组织工程研究 2025年第5期29卷 928-935页

作者：白静张雪任燕李月辉田晓宇唐山中心医院口腔科河北省唐山市063000 唐山市丰润区人民医院河北省唐山市063000 开滦(集团)有限责任公司唐家庄医院河北省唐山市063000 遵化市人民医院河北省遵化市064200

背景:LncRNA-TNFRSF13C是B细胞发育和功能中的一个重要因子,在牙周炎患者牙周组织中高表达,但具体机制还不清楚。目的:探讨lncRNA-TNFRSF13C调控miR-1246对牙周细胞低氧诱导因子1α的作用机制。方法:人牙周膜细胞经过脂多糖处理后分为7... 详细信息

背景:LncRNA-TNFRSF13C是B细胞发育和功能中的一个重要因子,在牙周炎患者牙周组织中高表达,但具体机制还不清楚。目的:探讨lncRNA-TNFRSF13C调控miR-1246对牙周细胞低氧诱导因子1α的作用机制。方法:人牙周膜细胞经过脂多糖处理后分为7组:A组(无转染的人牙周膜细胞株)、B组(人牙周膜细胞株转染TNFRSF13C NC-siRNA)、C组(人牙周膜细胞株转染TNFRSF13C-siRNA)、D组(人牙周膜细胞株转染miR-1246 mimics)、E组(人牙周膜细胞株转染miR-1246 siRNA)、F组(人牙周膜细胞株转染TNFRSF13C-siRNA+miR-1246 mimics)及G组(人牙周膜细胞株转染TNFRSF13C-siRNA+miR-1246 siRNA)。采用qRT-PCR检测各组细胞lncRNA-TNFRSF13C、miR-1246相对表达;CCK-8检测细胞活性;流式细胞仪检测细胞凋亡率;免疫印迹检测细胞中低氧诱导因子1α、血管内皮生长因子蛋白的表达;Pearson分析lncRNA-TNFRSF13C与miR-1246相关性,双荧光素酶分析靶向关系。结果与结论:①A、B两组人牙周膜细胞活性、凋亡率及蛋白指标比较差异均无显著性意义(P>0.05),与B组相比,C组细胞活性升高、凋亡率及低氧诱导因子1α、血管内皮生长因子蛋白降低(P<0.05),与C组相比,D组细胞活性降低,凋亡率及低氧诱导因子1α、血管内皮生长因子蛋白均升高(P<0.05),D组相比,E组细胞活性升高(P<0.05),F组细胞活性低于E组,E、F组细胞凋亡率降低(P<0.05),与F组相比,G组细胞活性升高、凋亡率及低氧诱导因子1α、血管内皮生长因子蛋白降低(P<0.05)。②lncRNA-TNFRSF13C与miR-1246呈现正相关(P<0.05)。③TNFRSF13C-siRNA组与TNFRSF13C-NC组在miR-1246-wt荧光活性降低(P<0.05);与miR-1246-NC组相比,miR-1246 mimics组低氧诱导因子1α-wt、血管内皮生长因子-wt荧光活性升高(P<0.05)。④结果说明,下调lncRNA-TNFRSF13C对脂多糖处理的牙周细胞具有促进活性、降低凋亡的作用,同时也可抑制低氧诱导因子1α、血管内皮生长因子的表达,其机制与调控miR-1246活性相关。

关键词：牙周炎牙周膜细胞脂多糖炎症 miR-1246 lncRNA-TNFRSF13C

Dopaminergic modulation of synaptic plasticity in rat prefrontal neurons

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Neuroscience Bulletin 2015年第2期31卷 183-190页

作者： Satoru Otani jing bai Kevin Blot Center for Medical Education Faculty of Health Sciences Ryotokuji University Chinese Medicine Research Laboratory Juntendo University Medical School Pathophysiology Department University of Paris 6

The prefrontal cortex （PFC） is thought to store the traces for a type of long-term memory - the memory that determines the temporal structure of behavior often termed a ＂rule＂ or ＂strategy＂. Long-term synaptic plasticity might serve as an underlying cellular mechanism for this type of memory. We therefore studied the induction of synaptic plasticity in rat PFC neurons, maintained in vitro, with special emphasis on the functionally important neuromodulator dopamine. First, the induction of long-term potentiation （LTP） was facilitated in the presence of tonic/background dopamine in the bath, and the dose-dependency of this background dopamine followed an ＂inverted-U＂ function, where too high or too low dopamine levels could not facilitate LTP. Second, the induction of long-term depression （LTD） by low-frequency stimuli appeared to be independent of background dopamine, but required endogenous, phasically-released dopamine during the stimuli. Blockade of dopamine receptors during the stimuli and exaggeration of the effect of this endogenouslyreleased dopamine by inhibition of dopamine transporter activity both blocked LTD. Thus, LTD induction also followed an inverted-U function in its dopamine-dependency. We conclude that PFC synaptic plasticity is powerfully modulated by dopamine through inverted-U-shaped dose-dependency.

关键词： prefrontal cortex synaptic plasticity long-term memory

Enantioselective Synthesis of cis-2,6-Disubstituted-4-methylene Tetrahy-dropyrans via Chromium Catalysis

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Chinese Journal of Chemistry 2020年第12期38卷 1642-1646页

作者： jing bai Bin Chen Guozhu Zhang State Key Laboratory of organometallic Chemistry Center for Excellence in Molecular Synthesis Shanghailnstitute of Organic ChemistryUniversty of Chinese Academy of SciencesChinese Academy of Sciences345 Lingling RoodShanghai 200032China

of main observation and conclusion Enantioenriched 2,6-disubstituted 4-methylene tetrahydropyrans have been obtained via a two-step sequence consisting of a highly enantioselective chromium-catalyzed carbonyl 2-(trimethylsilyl methyl)allylation and Prins *** available(2-(chloromethyl)allyl)trimethylsilane serves as the bifunctional linchpin to combine two aldehydes to assemble the 2,6-disubstituted pyrans.A variety of functional groups are compatible under the mild reaction *** synthetic utility of this methodology was demonstrated by the asymmetric synthesis of 16 examples of homoallylic alcohol and 8 examples of 2,6-disubstituted 4-methylene tetrahydropyrans,including an advanced intermediate which could be transformed to natural product centrolobine via a known procedure.

关键词： substituted methylene allyl

New deghosting method based on generalized triangulation

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Journal of Systems Engineering and Electronics 2009年第3期20卷 504-511页

作者： bai jing Wang Guohong Xiu Jianjuan Wang Xiaobo Inst. of Information Fusion Naval Aeronautical and Astronautical Univ. Yantai 264001 P. R. China

A new deghosting method based on the generalized triangulation is presented. First, two intersection points corresponding to the emitter position are obtained by utilizing two azimuth angles and two elevation angles from two jammed 3-D radars （or 2-D passive sensors）. Then, hypothesis testing based deghosting method in the multiple target scenarios is proposed using the two intersection points. In order to analyze the performance of the proposed method, the correct association probability of the true targets and the incorrect association probability of the ghost targets are defined. Finally, the Monte Carlo simulations are given for the proposed method compared with the hinge angle method in the cases of both two and three radars. The simulation results show that the proposed method has better performance than the hinge angle method in three radars case.

关键词： deghosting generalized triangulation hinge angle distributed radar network hypothesis testing

DNA damage in nucleosomes

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Science China Chemistry 2019年第5期62卷 561-570页

作者： Mengtian Ren jing bai Zhen Xi Chuanzheng Zhou State Key Laboratory of Elemento-Organic Chemistry and Department of Chemical Biology College of ChemistryNankai University

Eukaryotic genomic DNA is packed into chromatin, whose fundamental structural unit is the nucleosome. As DNA-histone protein complexes, nucleosomes show different properties toward exogenous and endogenous DNA-damaging agents. This review summarizes nucleosome DNA damage due to different sources, including alkylating agents, radicals, UV radiation and reactive DNA damage intermediates. In most cases, the histone core protects the associated DNA against damage via its structure and/or scavenging of damaging agents. In contrast, histones react with damaged DNA and, in some instances, catalyze DNA damage in the nucleosome. The biological consequence of nucleosome DNA damage and future prospects in this field are briefly discussed.

关键词： DNA damage DNA alkylation DNA-protein cross-link nucleosome radical reactive intermediate

Studies on Structure and Properties of Water Soluble Polysaccharide from Fruiting Body of Cordyceps Militarvs(L.) Link

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Chemical Research in Chinese Universities 2003年第1期19卷 37-40页

作者： WANG bai jing WEI Min ZHANG Li Ping School of Life Science Northeast Normal UniversityChangchun 130024P.R.China

A water soluble crude polysaccharide has been isolated from the fruiting body of cultivated Cordyceps militarvs(L.) Link. The GC analysis indicated that it contained the monosaccharides of Gal, Man, Glc and GlcA. Their molar ratio is 1 00∶1 58∶7 89∶0 19. The crude polysaccharide was fractionated with ethanol to get three fractions, which were CM Ⅰ, CM Ⅱ and CM Ⅲ. CM Ⅱ was further purified to get one homogeneous fraction named CMB. The molecular weight was estimated to be 60000 by means of gel filtration. CMB is a greyish white powder. The GC analysis indicated that it was composed of Gal, Man, Glc and the molar ratio is 1 00∶1 38∶5 10. Partial hydrolysis with an acid, periodate oxidation, Smith degradation, IR, GC and methylation analyses, GC/MS analyses were used for the structure analyses of CMB. The results reveal that CMB is of a lower branched structure. The main chain is composed of (1→6) linked Man, (1→6) linked Glc, (1→4) linked Glc and (1→4) linked Gal. Some of (1→4) linked Glc and all (1→4) linked Gal residues are substituted at 3 O and 6 O respectively. (1→4) Linked Glc residues without branch probably exist with other monosaccharides alternately. On an average, there is one branch every ten hexose residues. The side chain is composed of major (1→4) linked Glc and minor (1→6) linked Glc. The nonreduced end is composed of Gal and Glc. The main glycosidic link of CMB is α configuration.

关键词： Cordyceps militarvs(L.) Link Polysaccharide Structure Property

Combustion crack-network reaction evolution model for highly-confined explosives

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Defence Technology（防务技术） 2023年第8期26卷 54-67页

作者： Zhuo-ping Duan Meng-jing bai Zhi-ling bai Xin-jie Wang Feng-lei Huang State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing100081China

The evolution behavior of combustion crack reaction of highly confined solid explosives after non-shock ignition is governed by multiple dynamic processes,including intrinsic combustion of explosives,crack propagation,and rapid growth of combustion surface ***,the pressure increase can accelerate the combustion rate of explosives,and the crack propagation can enlarge the combustion surface *** coupling between these two effects leads to the self-enhanced combustion of explosive charge system,which is the key mechanism for the reaction development after *** this study,combustion cracknetwork(CCN) model is established to describe the evolution of combustion crack reaction of highly confined solid explosives after non-shock ignition and quantify the reaction *** feasibility of the model is verified by comparing the computational and experimental *** results reveal that an increase in charge structure size causes an increase in the time of crack pressurization and extension of cracks due to the high temperature-generated gas flow and surface combustion during the initial stage of explosive reaction,but when the casing is fractured,the larger the charge structure,the more violent the late reaction and the larger the charge reaction *** input pressure has no obvious influence on the final reaction ***,a larger venting hole area leads to better pressure relief effect,which causes slower pressure growth inside *** reserved ullage volume causes longer lowpressure induction stage,which further restrains the internal pressure ***,the stronger the casing constraint,the more rapid the self-enhanced combustion of the high temperaturegenerated gas,which results in more violent charge reaction and larger charge reaction degree during casing ***,the proposed model can clarify the effects of intrinsic combustion rate of explosives,charge structure size,input pressure,relief area,ullage volume,a

关键词： Solid explosives Non-shock ignition Self-enhanced combustion Combustion crack-network(CCN)model Relief area Reaction degree