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基于文本挖掘的颠覆性技术识别方法综述

情报工程 2024年第3期10卷 77-87页

作者：孙心怡梁洪振刘桂锋江苏大学科技信息研究所镇江212013

[目的/意义]对颠覆性技术的基础理论与识别方法进行梳理归纳有助于把握技术发展态势,推动数智时代面向科技创新的智能化情报服务体系构建。[方法/过程]明确颠覆性技术与文本挖掘方法的基础内涵,通过对该研究领域强关联的核心论文进行定... 详细信息

[目的/意义]对颠覆性技术的基础理论与识别方法进行梳理归纳有助于把握技术发展态势,推动数智时代面向科技创新的智能化情报服务体系构建。[方法/过程]明确颠覆性技术与文本挖掘方法的基础内涵,通过对该研究领域强关联的核心论文进行定性解读,将基于文本挖掘的颠覆性技术识别方法进行分类比较与组合分析。[局限]当前颠覆性技术识别领域应用的文本挖掘技术尚不成熟,需要进一步改进并与其他方法结合使用来优化识别效果。[结果/结论]基于文本挖掘的颠覆性技术识别方法包括突变词检测、术语词分析、共词分析、文本聚类、主题模型、语义分析。文本挖掘侧重从技术属性角度识别颠覆性技术,深度挖掘科技文本数据隐藏的潜在技术主题。

关键词：颠覆性技术技术识别文本挖掘技术范式创新突破性技术

CXCR4 Peptide Conjugated Au-Fe2O3 Nanoparticles for Tumor-targeting Magnetic Resonance Imaging

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Chemical Research in Chinese Universities 2018年第4期34卷 584-589页

作者： liu guifeng CHEN Hongda YU Shaonan LI Xiaodong WANG Zhenxin Department of Radiology China-Japan Union Hospital of Jilin University Changchun 130033 P. R. China State Key Laboratory of Eleetroanalytical Chemistry Changchun Institute of Applied Chemistry Chinese Aeademy of Sciences Changehun 130022 P R. China Department of Radiology the First Hospital of Jilin University Changchun 130021 P. R. China

Peptide-functionalized Au-Fe2O3 nanoparticles（termed as anti-CXCR4-Au-Fe2O3 NPs） have been constructed through conjugation of dumbbell-like Au-Fe203 NPs with C-X-C motif chemokine receptor 4（CXCR4） binding cyclic peptide. One dumbbelMike Au-Fe2O3NP composes an Au NP[（3.3±0.3） nm in diameter] for conjugating CXCR4 binding cyclic peptide through Au-S covalent bond and a Fe2O3 NP[（8.7±0.8） nm in diameter] for using as T2-weighted magnetic resonance imaging（MRI） contrast agent. The anti-CXCR4-Au-Fe2O3 NPs have reasonable biocompatibility and integration of T2-weighted MRI contrast and tumor-targeting functionalities. The anti- CXCR4-Au-Fe2O3 NPs exhibit strong interactions with two kinds of breast tumor cells, MCF-7 cells and MDA-MB-231 cells, and high negative contrast in MRI of MDA-MB-231 tumor bearing mouse with 62% decreasing of MRI signal, indicating that the anti-CXCR4-Au-Fe2O3 NPs can recognize tumor with high efficacy and specificity.

关键词： Dumbbell-like Au-Fe2O3 nanoparticle C-X-C motif chemokine receptor 4 Cyclic peptide T2-Weighted magnetic resonance imaging Tumor targeting ability

Analysis of three types of triterpenoids in tetraploid white birches(Betula platyphylla Suk.) and selection of plus trees

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Journal of Forestry Research 2015年第3期26卷 623-633页

作者： Sui Wang Hui Zhao Jing Jiang guifeng liu Chuanping Yang State Key Laboratory of Tree Genetics and Breeding Northeast Forestry University

Betulin, oleanolic acid, and betulinic acid are naturally occurring pentacyclic triterpenoids that have significant medicinal value. Considerable amounts of these triterpenoids are available in the outer bark of white birch. In this study, we used ultrasound-assisted extraction （UAE） to extract triterpenoids from birch bark rapidly and with high efficiency. Using high performance liquid chro- matography （HPLC）, three types of triterpenoids were separated and detected. We examined the differences among triterpenoids extracted from diploid versus tetra- ploid white birch. Then, we used factor analysis to screen out tetraploid white birches with comprehensively excel- lent performance. The results indicate that the optimum conditions for extraction include the use of ethanol as an extraction solvent, a solid-to-liquid ratio of 0.1 g/10 ml, ultrasonic power set at 100 W, a temperature of 60 ℃ and an extraction time of 15 min. A reversed-phase C18 col- umn （4.6 mm × 250 mm × 5 μm） with a column tem- perature of 30 ℃ and the mobile phase composed of A （acetonitrile） and B （0.1% aqueous phosphoric acid, v/v） at a flow rate of 0.5 ml/min were used, and the detection wavelength was 195 nm. No significant difference wasobserved between diploid and tetraploid white birch in terms of the content of three types of triterpenoids （at a confidence level of 0.05）. As triterpenoid content, height, and DBH （diameter at breast height） are strongly interre- lated, we used factor analysis to evaluate all individuals, and we screened out six plus trees with excellent com- prehensive characters.

关键词： Betula platyphylla Suk Triterpenoids Highperformance liquid chromatography (HPLC) Tetraploid Diploid Factor analysis

Selection of elite lines of BpGH3.5-transgenic Betula platyphylla using growth adaptability analysis

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Journal of Forestry Research 2022年第6期33卷 1891-1901页

作者： Chu Wang Yang Wang Jianjun Zou Rusheng Peng Qibin Yu guifeng liu Jing Jiang State Key Laboratory of Tree Genetics and Breeding Northeast Forestry UniversityHarbin 150040People’s Republic of China Jilin Provincial Academy of Forestry Sciences Changchun 130000People’s Republic of China Liaoning Poplar Research Institute Gaizhou 115200People’s Republic of China University of Florida GainesvilleFLUSA

White birch(Betula platyphylla)is precious material for pulpwood and widely distributed in 14 provinces of *** study indicated that inhibited expression of a gene encoding an auxin amide synthase,BpGH3.5,in transgenic plants reduced the level of IAA–amino acid conjugation,resulting in more free IAA,thereby better growth of *** transgenic-B pGH3.5 lines to increase wood production in a wide range of environments is the goal for *** three field trials here,we measured tree height,diameter at breast height,and volume of 16 BpGH3.5-transgenic 7-year-old white birch lines(including 12 antisense strand lines and 4 overexpression lines)and a wild-type white birch line from three sites that varied greatly in their environmental *** select elite BpGH3.5-transgenic lines for each target environment,we used an additive main effects and multiplicative interaction model to analyze genotype by environment interaction,growth adaptability and *** selection criteria for elite transgenic lines were set as the average volume plus 0.75 times the standard deviation for the tested lines at each test *** showed that the effect of line and site for height was highly significant(P<0.01),and the effect of line×site was significant(P<0.05);selected as the elite lines were FG12,FG13 and FG27 at the Maoershan Experimental Forest Farm,FG13 and FG32 at the Shidaohe Forest Farm,and FG3 and FG31 at the Ecological Experiment Forest *** seven high-yield,stable lines can now be tested in production trials or adjacent trial areas with similar environmental conditions,while the high-yield,unstable lines should be tested in production trials in areas deemed suitable for their *** results provide guidance on which released transgenic elite lines will grow best in a wide range of conditions.

关键词： Betula platyphylla BpGH3.5 Afforestation test Growth adaptability

Differentiation of illicit drugs with THz time-domain spectroscopy

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Nuclear Science and Techniques 2010年第4期21卷 209-213页

作者： liu guifeng MA Shihua JI Te ZHAO Hongwei WANG Wenfeng Shanghai Institute of Applied Physics Chinese Academy of Sciences Shanghai 201800 China

The terahertz time-domain spectroscopy(THz-TDS) was used for sensing and identifying illicit *** absorption spectra of seven illicit drug samples(morphine and its hydrochloride,cocaine hydrochloride,codeine phosphate,papaverine hydrochloride,pethidine hydrochloride,and thebaine) were studied by THz-TDS at 0.3-2.0 THz at room *** geometric structure and vibration frequencies of morphine were calculated by density functional *** four absorption features were dominated by intra-/inter-molecular collective or lattice vibration *** illicit drug has a distinct signature in its THz *** results indicate that the THz-TDS can be used to identify and discriminate illicit drugs by their characteristic fingerprints.

关键词：太赫兹时域光谱 THz 毒品密度泛函理论盐酸吗啡吸收光谱盐酸盐振动频率

BpMADS12 gene role in lignin biosynthesis of Betula platyphylla Suk by transcriptome analysis

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Journal of Forestry Research 2016年第5期27卷 1111-1120页

作者： Huiyu Li Yang Yang Zijia Wang Xiaohong Guo Feifei liu Jing Jiang guifeng liu State Key Laboratory of Tree Genetics and Breeding Northeast Forestry University College of Agricultural Sciences Heilongjiang Bayi Agricultural University

MADS-box transcription factors show highly diverse regulatory functions in a wide variety of organisms. In this study, we characterized a MADS-box gene （BpMADS12） from the white birch （Betula platyphylla Suk）. This gene is a member of the suppressor of overexpression of CO 1/tomato MADS 3 class of MADS-box genes. We generated lines overexpressing BpMADS12 and found that these had higher levels of lignin compared to that observed in nontransgenic lines. Transcriptome anal- ysis revealed numerous changes in gene expression patterns. In total, 8794 differentially expressed genes were identified, including 5006 upregulated unigenes and 3788 downregulated unigenes in BpMADS-overexpression lines. Differentially expressed genes involved in the pathways for lignin and brassinosteroid biosynthesis were significantly enriched and may have contributed to phenotypic changes. The results from a quantitative RT-PCR analysis were consistent those obtained with the transcriptome *** transcriptome analysis, in combination with measure- ment of lignin level, indicated that BpMADS12 promotes lignin synthesis through regulation of key enzymes in response to brassinosteroid signaling. These results suggest that this MADS-box protein is crucial to all subsequent structural events and provide a good foundation for studies aiming to elucidate the developmental mechanisms underlying formation of wood.

关键词： Betula platyphylla . BpMADS12 - Ligninbiosynthesis - Transcriptome analysis

Expression of BpPIN is associated with IAA levels and the formation of lobed leaves in Betula pendula ’Dalecartica’

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Journal of Forestry Research 2020年第1期31卷 87-97页

作者： Chang Qu Xiuyan Bian Rui Han Jing Jiang Qibin Yu guifeng liu State Key Laboratory of Tree Genetics and Breeding Northeast Forestry UniversityHarbinPeople’s Republic of China University of Florida Lake AlfredFLUSA

Auxin polar transport genes PIN(PINFORMED)determine the concentration gradient of auxin in *** understand the relationship between the development of different tissues in Betula pendula‘Dalecartica’,BpPIN gene expression and indole-3-acetic acid(IAA)content were analyzed using qRT-PCR,ELISA,and GUS *** expression of BpPIN genes and IAA levels in the leaves,buds,stems,xylem,and roots of ***‘Dalecartica’and *** as a control were ***1,BpPIN5 and BpPIN6 were upregulated during development in both species,suggesting a dominant role in the development of ***‘Dalecartica’***,BpPIN1 gene expression was positively associated with IAA levels during leaf,vein and petiole development in ***‘Dalecartica’*** correlation coefficient of the first three leaves was 0.69(P=0.04),while that of the first three petioles was 0.85(P=0.001).In addition,GUS staining of the pro-DR5::GUS transgenic line of cultivar was correlated with the results of BpPIN1 ***,these findings suggest that BpPIN1 is associated with the formation of lobed leaves in ***‘Dalecartica’.

关键词： Betula pendula Betula pendula‘Dalecartica’ BpPIN genes Gene expression IAA

Improved salt tolerance of Populus davidiana × P. bolleana overexpressed LEA from Tamarix androssowii

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Journal of Forestry Research 2014年第4期25卷 813-818页

作者： Yanshuang Sun Su Chen Haijiao Huang Jing Jiang Shuang Bai guifeng liu State Key Laboratory of Tree Genetics and Breeding (Northeast Forestry University)

Development of transgenic plants with tolerance to environ- mental stress is an important goal of plant biotechnology. （LEA） proteins accumulate in seeds dur- ing late embryogenesis, where they protect cellular membranes and macromolecules against drought. In this work, we transferred the Tamarix androssowii LEA gene into hybrids of Populus davidiana xp. bolleana. We compared relative rates of height growth, chlorophyll fluo- rescence kinetic parameters, and leaf Na＋ levels of six TaLEA-containing lines with non-transferred plants （NT）, all grown under 0.8% NaC1 stress condition. Survival percentages of transgenic lines were all higher than for NT controls after rehydration and the sur- vival percentage of SL2 was five-fold higher than for NT controls. Seed- ling height increased 48.7% in SL2 （from the onset of induced stress to the end of the growing season）, 31% more than for the NT controls. Chlorophyll fluorescence kinetic parameters showed a marked increase in photosynthetic capacity in SL2 and SL5. Na＋ levels in young leaves of transgenic lines were lower than in control NT leaves, but higher in yel- low and withered leaves, indicating improved salt tolerance in transgenic lines.

关键词： Populus davidiana x p. bolleana LEA gene transformation salt tolerance

基于转录组测序的关联分析定位裂叶桦叶形调控基因

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南京林业大学学报（自然科学版） 2024年第1期48卷 39-46页

作者：顾宸瑞袁启航姜静穆怀志刘桂丰林木遗传育种全国重点实验室(东北林业大学) 黑龙江哈尔滨150040 北华大学林学院吉林吉林132013

【目的】针对调控裂叶桦(Betula pendula‘Dalecarlica’)叶形的基因进行初步定位,筛选并注释可能的候选基因,为后续的验证实验和机理研究奠定基础。【方法】以来自1株裂叶桦母树的24株子代个体为试验材料,其包括了正常叶、浅裂叶、深... 详细信息

【目的】针对调控裂叶桦(Betula pendula‘Dalecarlica’)叶形的基因进行初步定位,筛选并注释可能的候选基因,为后续的验证实验和机理研究奠定基础。【方法】以来自1株裂叶桦母树的24株子代个体为试验材料,其包括了正常叶、浅裂叶、深裂叶等类型,扫描每单株的5个叶片,使用衡量叶片不规则度的指标计算每株个体的叶形不规则度,分析个体之间的差异显著性,测定每单株RNA-Seq数据,分析其中的SNP/InDel信息,并结合叶片不规则度进行关联分析,划定关联区。根据RNA-Seq数据分析实验材料全基因组的基因表达量,计算基因差异显著性,继而挑选出关联区中的差异基因。将关联区中受关联性SNP影响的基因和差异表达的基因作为候选基因,使用在线数据库进行基因功能注释。【结果】试验群体叶形不规则度的变异系数达60.51%,满足关联分析的需求。对实验群体全基因组中1367359个SNP/InDel标记的关联分析结果显示,裂叶桦叶形调控基因所在的关联区长9.18 MbP,包含400个基因,关联区内61个关联性SNP影响了17个基因的编码。基因表达量分析结果显示,关联区中有25个基因在不同叶形桦树之间存在极显著差异(P<0.01)。对上述候选基因进行功能注释,根据注释结果,预测其中3个转录因子和1个生长素转运蛋白可能是调控裂叶桦叶形的关键基因。【结论】调控裂叶桦叶片分裂性状的基因定位在7号染色体7466344—16651477的区间,包含候选基因40个。根据基因注释结果,建议后续研究重点针对其中3个转录因子和1个生长素外排体基因开展。

关键词：裂叶桦叶形转录组测序关联分析

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