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Agricultural Sciences in China 2009年第11期8卷 1351-1359页

作者： ZHAO Ying LIU na niu Jian-xin Horticultural Department Agricultural College Shihezi University Shihezi 832003 P.R. China

To understand the distribution of Apple stem pitting virus （ASPV） in tissues of pear tree and provide directly theorical and technical support for shoot tips detoxication, leaves and shoot tips of Korla pear were used as the materials, cDna probe for ASPV was synthesized through RT-PCR reaction system using the unradioactive digoxigenin-labeled probe, and the specificity and sensitivity of probe were verified by blot hybridization method. Paraffin slice for in situ PCR and in situ hybridization was made and the location and distribution of ASPV Rna were detected in paraffin slices using in situ reverse transcription polymerase chain reaction, and the important factors which influenced the experiment results were optimized. ASPV mainly distributed in palisade tissue of mesophyll cells, external cortex of the tip, and the corresponding newborn vascular bundles. 20 min was the suitable digestive time for proteinase K. For the better amplication, RT reaction system should be above 0.2 U μL^-1 and 0.4 mmol L^-1 for Rnasin and dNTPs respectively, 0.1-1.3 U μ L^-1 SuperScript Ⅱ, 0.6- 0.8 μmol L^-1 primer concentration, and above 0.5 U 100 μL^-1 LA Taq Dna polymerase. The suitable annealing temperature in PCR reaction was 60℃ with 35 cycles. The apical meristem of 0.25 mm was the region of virus-free.

关键词： Korla pear Apple stem pitting virus cDna probe digoxigenin in situ PCR

A Low-Complexity PTS Based on Greedy and Genetic Algorithm for OFDM Systems

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Chinese Journal of Electronics 2015年第4期24卷 857-861页

作者： LUO Renze ZHANG Chengsen niu na LI Rui State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Southwest Petroleum University University of Electronic Science and Technology of China

Partial transmit sequence(PTS) is one of effective technique to reduce high Peak-to-average power ratio(PAPR) in Orthogonal frequency division multiplexing(OFDM) system. However, the complexity of Original PTS(O-PTS) increases exponentially with the number of sub-blocks. To reduce the computational complexity while still offering a lower PAPR, a new PTS method is proposed to search for suboptimal rotating vectors in this paper. In the proposed method, the candidate rotation vectors are generated based on greedy and genetic *** also combine the proposed method and the superimposed training sequence method to get a further PAPR reduction. The theory and simulations results show that the proposed method can achieve better PAPR reduction and significantly reduce the computational complexity.

关键词： PTS PAPR reduction OFDM Suboptimal rotating vectors

Preparation and Characterization of SiO2/Co and C/Co nanocomposites as Fisher-Tropsch Catalysts for CO2 Hydrogenation

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Chemical Research in Chinese Universities 2018年第4期34卷 635-642页

作者： HAN Fuqin ZHANG Zhe niu na LI Jian College of Science Northeast Forestry University Harbin 150040 P. R. China Key Laboratory of Bio-based Material Science and Technology Ministry of Education Northeast Forestry University Harbin 150040 P. R. China

To fabricate high-density cobalt-based catalysts, we first synthesized SiO]C composites via a hydrother- mad method and removed C and SiO2 by two different methods, respectively. The as-prepared SiO2 and C supports then reacted with cobalt acetylacetonate and N,N-dimethylformamide（DMF） under hydrothermal conditions to prepare SiO2/Co and C/Co nanocomposite catalysts. The catalysts were characterized by X-ray difffaction（XRD）, scanning electron microscope（SEM）, transmission electron microscopy（TEM）, inductively coupled plasma mass spectrometry（ICP）~ energy dispersive X-ray fiuoresence spectrometer（EDX）, and nitrogen adsorption. It was found that hexagonal cobalt nanocrystals were successfully integrated with the mesoporous silica or carbon nanotube supports. SEM and TEM results show that SiO2/Co composites with a hollow/mesoporous sphere structure and C/Co composites with a tubular structure have been successfully synthesized. Both composite samples show superpara- magnetism exhibiting an S-type hysteresis loop, which originated from the cobalt nanoparticles in the samples. Nitrogen adsorption/desorption curves suggest that the SiO2 and C supports have well-developed pore structures and large specific surface areas, and the loading and good dispersity of cobalt nanoparticles on the supports were proven by ICP and EDX. Moreover, the samples exhibited good and stable catalytic activity, denlonstrating that the two composites are suitable catalysts for Fischer-Tropsch CO2 hydrogenation.

关键词： Mesoporous SiO2 Carbon nanotube Cobalt based catalyst Fischer-Tropseh reaction CO2 hydrogenation

Multivariate chemical analysis:From sensors to sensor arrays

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Chinese Chemical Letters 2024年第7期35卷 14-24页

作者： Xueling Yu Lixing Fu Tong Wang Zhixin Liu na niu Ligang Chen College of Chemistry Chemical Engineering and Resource UtilizationKey Laboratory of Forest Plant EcologyNortheast Forestry UniversityHarbin 150040China

Chemical sensor arrays can obtain more comprehensive analyte information through high-dimensional *** is of great significance in the analysis of multi-component complex *** review summarizes the development and status of chemical sensor *** focused on the design of chemical sensor arrays based on various sensing *** addition,several pattern recognition methods in chemometrics are *** applications of chemical sensor arrays in food monitoring,medical diagnosis,and environmental monitoring are *** on the analysis of the limitations of current sensor array technology,the direction of the array is also *** review aims to help the broad readership understand the research state of chemical sensor arrays and their development prospects.

关键词： Chemical sensor arrays Sensing materials Pattern recognition methods Analytical application

The integration of peri-implant soft tissues around zirconia abutments:Challenges and strategies

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Bioactive Materials 2023年第9期27卷 348-361页

作者： Kai Tang Meng-Lin Luo Wei Zhou Li-na niu Ji-Hua Chen Fu Wang national Clinical Research Center for Oral Diseases&State Key Laboratory of Military Stomatology&Shaanxi Key Laboratory of Stomatology Department of ProsthodonticsSchool of StomatologyThe Fourth Military Medical UniversityXi’anShaanxi710032China Institute of Stomatology&Oral Maxilla Facial Key Laboratory The First Medical CenterChinese PLA General Hospital&Department of StomatologyThe First Medical CenterChinese PLA General HospitalBeijingChina

Stable soft tissue integration around the implant abutment attenuates pathogen penetration,protects underlying bone tissue,prevents peri-implantitis and is essential in maintaining long-term implant *** desire for“metal free”and“aesthetic restoration”has favored zirconia over titanium abutments,especially for implant restorations in the anterior region and for patients with thin gingival *** tissue attachment to the zirconia abutment surface remains a challenge.A comprehensive review of advances in zirconia surface treatment(micro-design)and structural design(macro-design)affecting soft tissue attachment is presented and strategies and research directions are *** tissue models for abutment research are *** for development of zirconia abutment surfaces that promote soft tissue integration and evidence-based references to inform clinical choice of abutment structure and postoperative maintenance are presented.

关键词： Zirconia Implant abutment Surface modification Soft tissue adhesion

Fabricating UCNPs-AuNPs Fluorescent Probe for Sensitive Sensing Thiamphenicol

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Chemical Research in Chinese Universities 2022年第6期38卷 1453-1460页

作者： YI Jiaqi LI Xiaoshuang CUI Di HAN Lixia JIANG Wei ZHANG Renguo niu na CHEN Ligang Key Laboratory of Forest Plant Ecology College of ChemistryChemical Engineering and Resource UtilizationNortheast Forestry UniversityHarbin150040P.R.China

A novel fluorescent probe has been constructed based on fluorescence resonance energy transfer(FRET)between upconversion nanomaterials(UCNPs)naYF4:Yb,Er and gold nanoparticles(AuNPs).The fluorescent“off-on”switching was formed for the detection of thiamphenicol(TAP)in egg *** fluorescence of UCNPs can be quenched to a certain degree by *** adding TAP,the AuNPs generated aggregation and the fluorescence of UCNPs was *** synthesized amination UCNPs and AuNPs were characterized by Fourier transform infrared spectroscopy(FTIR),UV-Vis,X-ray diffraction(XRD),energy dispersive spectrometer(EDS),and transmission electron microscope(TEM)techniques for observation and *** a model target,the detection of TAP has two linear ranges in the buffer solution within 0.01–0.1µmol/L and 0.1–1µmol/L using this fluorescent *** detection limit was obtained to be 0.003µmol/L(S/N=3),which is favorable for trace *** recovery of TAP from 98.2%to 105.3%was obtained,and the relative standard deviation(RSD)was from 2.5%to 4.3%.Furthermore,the method established in this study based on the UCNPs auto-low background fluorescence has high selectivity and strong ability to eliminate interference,which is beneficial to analyzing complex samples.

关键词： Upconversion nanomaterial Fluorescent switch Thiam-phenicol Fluorescence resonance energy transfer Egg analysis

New insights into IL-7 signaling pathways during early and late T cell development

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Cellular & Molecular Immunology 2013年第3期10卷 187-189页

作者： na niu Xuebin Qin Department of Pathology Weifang Medica University Weifang China Department o Medicine Brigham and Women's Hospital Harvard Medical School Boston MA USA

IL-7, a cytokine secreted mainly by stromal cells in the bone marrow and thymus, has been recognized to be critical for the development of all lymphocytes.1 However, the underlying mechanisms through which IL-7-mediated signaling contributes to early T-cell development and to mature T-cell maintenance are not yet completely understood. Two recently published studies in nature Immunology reported that a newly iden- tified IL-7 signaling pathway acts during early T-cell development and documented how IL-7 Signaling interacts with the T-cell antigen receptor （TCR） to influence mature T-cell survival.2＇3

关键词： T淋巴细胞白细胞介素7 变态反应和免疫学间质细胞淋巴细胞前体细胞淋巴母细胞白血病淋巴瘤受体抗原 T细胞维修

表面增强拉曼光谱的基底设计及其血液检测研究进展

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应用化学 2025年第1期42卷 1-13页

作者：蔡云帆许克惠赵耀李之婷夏凌云王晨语罗志晓牛丽娜湖北医药学院附属太和医院口腔医学中心口颌系统重建与再生全国重点实验室国家口腔疾病临床医学研究中心陕西省口腔医学重点实验室空军军医大学口腔医院修复科

表面增强拉曼光谱（SERS）因其独有的快速检测、高灵敏度、低检测限和无损分析等优点，在医学检验领域有着广泛的研究。SERS增强基底的成功构建是SERS技术实现以上优点的前提。本文介绍了SERS的增强机制，在血液检测中，对其增强基底的... 详细信息

表面增强拉曼光谱（SERS）因其独有的快速检测、高灵敏度、低检测限和无损分析等优点，在医学检验领域有着广泛的研究。SERS增强基底的成功构建是SERS技术实现以上优点的前提。本文介绍了SERS的增强机制，在血液检测中，对其增强基底的设计进行了分类及讨论，将其分为无标签基底和有标签基底两大类，并根据材料应用的不同和基底设计的方式不同进行进一步的细分。对近年来血液检测中SERS检测应用相关文献进行了回顾，综述了在血液检验中不同类型增强基底的设计方法及应用特征。最后，对SERS增强基底在血液检验中的设计进行了总结与展望。

关键词：表面增强拉曼光谱增强机制无标签基底有标签基底血液检测

HPLC Fingerprint Combined with Chemometrics and Network Pharmacology for Q-Markers Prediction Analysis of Saposhnikovia divaricata

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Journal of Analysis and Testing 2024年第1期8卷 83-94页

作者： Renguo Zhang Xinjian Liu Tong Wang Jie Yu Mengyuan Wang Jianmin Sun Xueling Yu na niu Ligang Chen College of Chemistry Chemical Engineering and Resource UtilizationKey Laboratory of Forest Plant EcologyNortheast Forestry UniversityHarbin 150040China

Saposhnikovia divaricata(SD)has high medicinal and edible value,but relatively little research has been done on its qual-ity markers(Q-markers).To further clarify the Q-markers of SD with their corresponding pharmacodynamic *** this experiment,14 batches of SD were identified and screened for Q-marker candidate components using a combination of HPLC fingerprint with similarity analysis,principal component analysis,hierarchical cluster analysis,and partial least squares discriminant ***,network pharmacology was used to predict Q-markers and core *** results showed that 5-O-methylvisammioside,cimifugin,and prim-O-glucosylcimifugin could be used as Q-markers of SD;while,MAPK1,MAPK3,PIK3CA,JUN,and MAPK8 were the core targets of SD for drug *** further evaluate the bind-ing efficiency of Q-markers,molecular docking of the main active ingredients of SD to the core targets was *** results showed that the compounds bind well to their targets,and binding energies were all less than-5 kcal/*** Q-markers obtained from the screening were closely related to the core target genes,which could achieve therapeutic effects by modulating the relevant signaling *** study offers a reference for the establishment of a set of quality control evaluation system for SD potential Q-markers prediction analysis,and lays the foundation for elucidating the mechanism of actionunderlying itspharmacodynamic substance.

关键词： Saposhnikovia divaricata Q-markers Fingerprint Chemometrics Network pharmacology Molecular docking

The Prediction of Rice Gene by Fgenesh

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Agricultural Sciences in China 2008年第4期7卷 387-394页

作者： ZHANG Sheng-li LI Dong-fang ZHANG Gai-sheng WANG Jun-wei niu na Shaanxi Key Laboratory of Crop Heterosis Northwest A ＆ F University Yangling 712100 P.R. China Key Discipline Open Laboratory on Crop Molecular Breeding Henan Institute of Higher Learning/Henan Institute of Science andTechnology Xinxiang 453003 P.R.China School of Resources and Environmental Sciences Henan Institute of Science and Technology Xinxiang 453003 P.R.China

This study has been carried out to give some scientific reasons for genome annotation, shorten the annotating time, and improve the results of gene prediction. Taking the sequence of the 6th chromosome, which has more length sequences than others, of Oryza sativa L. ssp. japonica cv. Nipponbare as analysis data in this research, the gene prediction of monocots module, rice, has been done by using Fgenesh ver. 2.0, and the predicting results have been explored particularly by bioinformatics methods. Results showed that the number of predicted genes for this chromosome was very close to the number of TIGR annotated genes. The majority of the predicted genes were multi-exon genes which had a percentage of 77.52. Length range was very big in the predicted genes. According to the significant match number, multi-exon genes can be predicted more veracity than single exon genes and the support can be reached up to 100% by TIGR annotation and up to 78% by cDna. From the angle of predicted exons location of multi-exon genes, the internal exons and last exons had a high support of cDna. The length of internal exons was relatively short in high （〉95% length, 〉78% similarity） cDna and/or TIGR annotation support multi-exon genes, but the first exons and last exons were on the reverse. The majority of single exon genes which had more than 95% in length, and 78% in similarity support by cDna and/or TIGR annotation was relatively short in length. From the angle of exon number, the majority of the multi-exon genes of high （〉 95% length, 〉 78% similarity） cDna and/or TIGR annotation support had no more than 5 exon number. It was concluded that the rice gene prediction by Fgenesh was very good but needed modification manually to some extent according to cDna support after aligning the predicting sequence of genes with cDna database of rice.

关键词： rice gene prediction cDna annotation exon