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Nitrogen-doped carbon@TiO_(2) double-shelled hollow spheres as an electrochemical sensor for simultaneous determination of dopamine and paracetamol in human serum and saliva

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Journal of Pharmaceutical Analysis 2022年第3期12卷 436-445页

作者： Hui Yang Gongxun Cao Yongjun Huang Ye lin Fengying Zheng Luxiu lin Fengjiao liu Shunxing Li College of Chemistry Chemical Engineering and EnvironmentMinnan Normal UniversityZhangzhouFujian363000China Fujian Provincial Key Laboratory of Pollution Monitoring and Control Minnan Normal UniversityZhangzhouFujian363000China Fujian Key Laboratory of Separation and Analysis Science and Technology ZhangzhouFujian363000China

As the most commonly used antipyretic and analgesic drug,paracetamol(PA)coexists with neurotransmitter dopamine(DA)in real biological samples.Their simultaneous determination is extremely important for human health,but they also interfere with each other.In order to improve the conductivity,adsorption affinity,sensitivity,and selectivity of TiO_(2)-based electrochemical sensor,N-doped carbon@-TiO_(2) double-shelled hollow sphere(HeC/N@TiO_(2))is designed and synthesized by simple alcoholic and hydrothermal method,using polystyrene sphere(PS)as a template.Meanwhile,TiO_(2) hollow spheres(H eTiO_(2))or N-doped carbon hollow spheres(HeC/N)are also prepared by the same method.HeC/N@TiO_(2) has good conductivity,charge separation,and the highly enhanced and stable current responses for the detection of PA and DA.The detection limit and linear range are 50.0 nmol/L and 0.3-50 mmol/L for PA,40.0 nmol/L and 0.3e50 mmol/L for DA,respectively,which are better than those of carbon-based sensors.Moreover,this electrochemical sensor,with high selectivity,strong anti-interference,high reliability,and long time durability,can be used for the simultaneous detection of PA and DA in human blood serum and saliva.The high electrochemical performance of HeC/N@TiO_(2) is attributed to the multifunctional combination of different layers,because of good conductivity,absorption and electrons transfer ability from in-situ N-doped carbon and electrocatalytic activity from TiO_(2).

关键词： Electrochemical sensor Simultaneous determination Paracetamol Dopamine

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A preliminary study of the weathering mechanism of fossilized Cretaceous Hamipterus bones

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Science China Earth Sciences 2021年第3期64卷 458-469页

作者： Ying li Wugan LUO Yimin YANG shunxing JIANG Xiaolin WANG Key Laboratory of Vertebrate Evolution and Human Origins of Chinese Academy of Sciences Institute of Vertebrate Paleontology and PaleoanthropologyChinese Academy of SciencesBeijing100044China Department of Archaeology and Anthropology University of Chinese Academy of SciencesBeijing100049China CAS Center for Excellence in life and Paleoenvironment Beijing100044China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing100049China

The discovery of Hamipterus tianshanensis had important scientific significance because three-dimensional preserved fossils can provide unique information about the reproduction,development,and evolution of pterosaurs.However,the pterosaur fossils exhibited violent weathering,including noticeable cracking and spalling,since the preservation environment changed dramatically after excavation,which severely influenced the preservation of these fossils and the scientific research conducted on them.To determine the weathering mechanism of these fossil bones,the samples were analyzed using X-ray fluorescence(XRF),Fourier transform infrared spectroscopy(FTIR),X-ray diffraction(XRD),scanning electron microscopy and energy dispersive spectrometry(SEM-EDS).The results indicate that calcite is the main mineral in the hollow bones,but it is mixed with a small amount of other minerals,such as quartz,feldspar,and other debris particles.Moreover,the main component of the pterosaur bones is hydroxyapatite,and carbonate has substituted for some of the phosphate(B-type carbonated apatite)in the fossil bones.A small amount of calcite and manganese oxides has precipitated in the vascular canals.The phosphate crystallinity index(PCI)is 4.17.These results indicate that the fossils have undergone severe diagenesis.Apart from these alterations,the fossil bones have high contents of anions and cations such as Cl^(-),NO_(3)^(-),SO_(4)^(2-),Na^(+),and Ca^(2+),and the total content of soluble salts is 35584.41μg g^(-1).Based on these results,it is inferred that the weathering mechanism of the fossil bones is as follows.First,the fragile hollow bones cracked easily because of the enormous thermal stress caused by the dramatic temperature changes in the Gobi Desert and the differences in the thermal expansion coefficients(TEC)of the surrounding rocks,the fossil bones,and the different fillers.Second,a large amount of stress is generated by salt crystallization when the temperature and humidity change,and the pterosaur fossils will be damaged

关键词： Hamipterus fossil weathering hydroxyapatite coefficient of thermal expansion Xinjiang

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Screening for differentially expressed genes in Anoectochilus roxburghii (Orchidaceae) during symbiosis with the mycorrhizal fungus Epulorhiza sp.

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Science China(life Sciences) 2012年第2期55卷 164-171页

作者： li Biao TANG MingJuan TANG Kun ZHAO liFang GUO shunxing Center of Biotechnology Institute of Medicinal Plant DevelopmentChinese Academy of Medical SciencesBeijing 100193China College of Bioinformation Chongqing University of Posts&TelecommunicationsChongqing 400065China

Mycorrhizal fungi promote the growth and development of plants, including medicinal plants. The mechanisms by which this growth promotion occurs are of theoretical interest and practical importance to agriculture. Here, an endophytic fungus (AR-18) was isolated from roots of the orchid Anoectochilus roxburghii growing in the wild, and identified as Epulorhiza sp. Tissue-cultured seedlings of A. roxburghii were inoculated with AR-18 and co-cultured for 60 d. Endotrophic mycorrhiza formed and the growth of A. roxburghii was markedly promoted by the fungus. To identify genes in A. roxburghii that were differentially expressed during the symbiosis with AR-18, we used the differential display reverse transcription polymerase chain reaction (DDRT-PCR) method to compare the transcriptomes between seedlings inoculated with the fungus and control seedlings. We amplified 52 DDRT-PCR bands using 15 primer combinations of three anchor primers and five arbitrary primers, and nine bands were re-amplified by double primers. Reverse Northern blot analyses were used to further screen the bands. Five clones were up-regulated in the symbiotic interaction, including genes encoding a uracil phosphoribosyltransferase (UPRTs; EC 2.***.2.9) and a hypothetical protein. One gene encoding an amino acid transmembrane transporter was down-regulated, and one gene encoding a tRNA-Lys (trnK) and a maturase K (matK) pseudogene were expressed only in the inoculated seedlings. The possible roles of the above genes, especially the UPRTs and matK genes, are discussed in relation to the fungal interaction. This study is the first of its type in A. roxburghii.

关键词：差异表达基因菌根真菌金线莲共生期逆转录聚合酶链反应 SP DDRT-PCR Northern

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猪苓糖苷水解酶家族基因及其差异表达

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菌物学报 2023年第10期42卷 2100-2110页

作者：李兵刘柳郭顺星中国医学科学院北京协和医学院药用植物研究所北京100193

猪苓与蜜环菌建立共生关系时,猪苓菌丝会反侵染并消解蜜环菌菌索,以获取营养物质,糖苷水解酶是参与这一过程的主要酶类之一。本研究从猪苓转录数据库中获得糖苷水解酶家族基因42类、309个;其编码的糖苷水解酶蛋白含各类结构域344个,以... 详细信息

猪苓与蜜环菌建立共生关系时,猪苓菌丝会反侵染并消解蜜环菌菌索,以获取营养物质,糖苷水解酶是参与这一过程的主要酶类之一。本研究从猪苓转录数据库中获得糖苷水解酶家族基因42类、309个;其编码的糖苷水解酶蛋白含各类结构域344个,以糖苷水解酶结构域glyco_hydro为主,共计35类173个。对猪苓糖苷水解酶进行的gene ontology(GO)功能注释结果表明,这些蛋白参与的生物学过程以物质代谢及分解过程为主,特别是多糖等大分子物质代谢;181个猪苓糖苷水解酶具有水解酶活性,这些水解酶活性呈多样性分布。与未被蜜环菌侵染的猪苓部位相比,43个糖苷水解酶基因在蜜环菌侵染的菌核部位中差异表达,编码包括glyco_hydro_48、cellulase和polysacc_deac_1等功能结构域,可能发挥水解几丁质、纤维素酶活性及免疫调节等活性,这为猪苓与蜜环菌互作关系的研究提供了候选基因及蛋白。

关键词：猪苓糖苷水解酶家族糖苷水解酶家族结构域

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赖氨酸基序(LysM)在植物–真菌相互作用中的研究进展

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植物生理学报 2022年第12期58卷 2263-2272页

作者：刘柳李兵郭顺星中国医学科学院北京协和医学院药用植物研究所北京100193

植物和真菌之间存在复杂的相互作用。真菌中含有的一些聚糖物质,如细胞壁中的几丁质,对激活植物免疫具有重要意义。赖氨酸基序(LysM)是一种广泛分布于原核生物和真核生物中的结构域,能够识别并结合这些聚糖物质,在植物–真菌相互作用中... 详细信息

植物和真菌之间存在复杂的相互作用。真菌中含有的一些聚糖物质,如细胞壁中的几丁质,对激活植物免疫具有重要意义。赖氨酸基序(LysM)是一种广泛分布于原核生物和真核生物中的结构域,能够识别并结合这些聚糖物质,在植物–真菌相互作用中起关键作用。植物LysM蛋白主要作为模式识别受体发挥作用,感知几丁质以诱导植物免疫。相反,真菌LysM能够保护细胞壁不被植物几丁质酶水解,阻断几丁质信号的感应或传导,从而抑制几丁质诱导的宿主免疫。本文对植物和真菌中LysM的研究现状以及LysM和植物–真菌相互作用的关系进行综述,以期为植物和真菌相互作用机制的深入研究提供参考。

关键词： LysM 几丁质植物免疫系统植物–真菌相互作用

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RNA barcode segments for SARS-CoV-2 identification from HCoVs and SARSr-CoV-2 lineages

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Virologica Sinica 2024年第1期39卷 156-168页

作者： Changqiao You Shuai Jiang Yunyun Ding shunxing Ye Xiaoxiao Zou Hongming Zhang Zeqi li Fenglin Chen Yongliang li Xingyi Ge Xinhong Guo College of Biology Hunan UniversityChangsha410082China College of Bioscience and Biotechnology Hunan Agricultural UniversityChangsha410128China

Severe acute respiratory syndrome coronavirus 2(SARS-CoV-2),the pathogen responsible for coronavirus disease 2019(COVID-19),continues to evolve,giving rise to more variants and global reinfections.Previous research has demonstrated that barcode segments can effectively and cost-efficiently identify specific species within closely related populations.In this study,we designed and tested RNA barcode segments based on genetic evolutionary relationships to facilitate the efficient and accurate identification of SARS-CoV-2 from extensive virus samples,including human coronaviruses(HCoVs)and SARSr-CoV-2 lineages.Nucleotide sequences sourced from NCBI and GISAID were meticulously selected and curated to construct training sets,encompassing 1733 complete genome sequences of HCoVs and SARSr-CoV-2 lineages.Through genetic-level species testing,we validated the accuracy and reliability of the barcode segments for identifying SARS-CoV-2.Subsequently,75 main and subordinate species-specific barcode segments for SARS-CoV-2,located in ORF1ab,S,E,ORF7a,and N coding sequences,were intercepted and screened based on single-nucleotide polymorphism sites and weighted scores.Post-testing,these segments exhibited high recall rates(nearly 100%),specificity(almost 30%at the nucleotide level),and precision(100%)performance on identification.They were eventually visualized using one and two-dimensional combined barcodes and deposited in an online database(http://virusbarcodedatabase.top/).The successful integration of barcoding technology in SARS-CoV-2 identification provides valuable insights for future studies involving complete genome sequence polymorphism analysis.Moreover,this cost-effective and efficient identification approach also provides valuable reference for future research endeavors related to virus surveillance.

关键词： RNA barcode segments SARS-CoV-2 variants and related lineages HCoVs Genetic tests Complete genome sequences

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Copper nanoparticles modified nitrogen doped reduced graphene oxide 3-D superstructure for simultaneous determination of dihydroxybenzene isomers

Copper nanoparticles modified nitrogen doped reduced graphen...

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中国化学会第十九届全国有机分析及生物分析学术研讨会

作者： Haifeng Zhou Tingting Huang Dejian Chen Shunxing Li Huiwu Yu Yuhui li Qijun Song The Key Lab of Food Colloids and Biotechnology Ministry of EducationSchool of Chemical and Material EngineeringJiangnan University Department of Chemistry and Environment Minnan Normal University

＜正＞3-D superstructure of Copper nanoparticles modified nitrogen doped reduced graphene oxide was successively prepared via a two-step reaction.Polydopamine was used as nitrogen source for the fabrication of nitrogen doped reduced graphene oxide and reducing agent for in-situ reduce ofThe electrochemical sensor was constructed by hybrid material-based

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Effect of Ag addition on the thermal stability and glass-forming ability of Zr_(35)Ti_(30)Cu_(7.5)Be_(27.5) bulk metallic glass

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Chinese Science Bulletin 2012年第11期57卷 1219-1222页

作者： ZONG HaiTao ZHANG XinYu li liXin BIAN linYan liANG shunxing TAN Chunlin State Key Laboratory of Metastable Materials Science and Technology Yanshan UniversityQinhuangdao 066004China College of Physics and Chemistry Henan Polytechnic UniversityJiaozuo 454000China

The thermal stability and glass forming ability (GFA) of Zr35-xTi30Cu7.5Be27.5Agx (x = 0-10) alloys were studied by X-ray diffraction (XRD), differential scanning calorimetry (DSC) and ultrasonic techniques. We found that the addition of 1 at.% Ag can considerably enhance the GFA as indicated by an increase in the critical glass dimension from 15 mm in the Zr35Ti30Cu7.5Be27.5 alloy to 20 mm in the Zr34Ti30Cu7.5Be27.5Ag1 alloy. However, with the addition of more Ag the supercooled liquid region (△Tx) and y parameter (defined as Tx/(Tg+Tl)) drastically decreased from 155 K and 0.436 to 76 K and 0.363, respectively, resulting in a decrease in the GFA. Additionally, the elastic constant (the ratio of shear modulus to bulk modulus or Poisson's ratio) was also used as a gauge to evaluate the GFA in Zr35-xTi30Cu7.5Be27.5Agx alloys.

关键词：玻璃形成能力热稳定性大块金属玻璃建筑面积银 X射线衍射仪差示扫描量热体积弹性模量

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新疆准噶尔盆地发现世界最大的亚洲足迹

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科学通报 2020年第18期65卷 1875-1887页

作者：李阳蒋顺兴汪筱林中国科学院古脊椎动物与古人类研究所脊椎动物演化与人类起源重点实验室北京100044 中国科学院生物演化与环境卓越创新中心北京100044 中国科学院大学地球与行星科学学院北京100049

在新疆准噶尔盆地西北缘乌尔禾地区下白垩统吐谷鲁群胜金口组,发现保存在灰绿色细砂岩层面上的13个恐龙足迹,形成3条行迹和4个孤立足迹.通过对足迹、行迹特征的详细观察研究,识别出两种足迹类型,其中大型三趾型足迹为一兽脚类足迹新种.... 详细信息

在新疆准噶尔盆地西北缘乌尔禾地区下白垩统吐谷鲁群胜金口组,发现保存在灰绿色细砂岩层面上的13个恐龙足迹,形成3条行迹和4个孤立足迹.通过对足迹、行迹特征的详细观察研究,识别出两种足迹类型,其中大型三趾型足迹为一兽脚类足迹新种.依据其尺寸大(长47.0~56.0 cm、宽31.0~42.0 cm)、趾行式、无拇趾印迹和尾迹、轴对称、V字形、蹠趾垫(脚跟)明显等特征,将其归入实雷龙足迹科(Eubrontidae)亚洲足迹属,并建立一个新种:Asianopodus niui ichnosp.nov.(牛氏亚洲足迹),这是目前发现的最大亚洲足迹.中型三趾型足迹相对较小(长21.0~27.0 cm、宽18.0~20.0 cm)、趾行式、无拇趾印迹和尾迹、轴对称、外侧趾间角为46.63°~51.40°、蹠趾垫印迹明显,归入跟垫亚洲足迹(Asianopodus pulvinicalx).相关分析表明,两种足迹类型的造迹恐龙都处于漫步状态,行走于滨浅湖环境.

关键词：亚洲足迹恐龙行迹下白垩统准噶尔盆地新疆乌尔禾

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不平衡数据分类的类依赖属性加权朴素贝叶斯算法改进

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应用数学 2022年第2期35卷 463-468页

作者：樊顺星李楚进沈澳华中科技大学数学与统计学院湖北武汉430074 华盛顿大学文理学院华盛顿西雅图98195

朴素贝叶斯分类器(Naïve Bayes,NB)是一种简单而有效的分类器,特别适用于中小规模数据分类.但作为以整体分类正确率为指导的传统分类方法,它在不平衡数据分类中对少数类的分类能力较弱.针对此问题,本文采用属性加权的方法增强朴素贝叶... 详细信息

朴素贝叶斯分类器(Naïve Bayes,NB)是一种简单而有效的分类器,特别适用于中小规模数据分类.但作为以整体分类正确率为指导的传统分类方法,它在不平衡数据分类中对少数类的分类能力较弱.针对此问题,本文采用属性加权的方法增强朴素贝叶斯对于少数类的分类能力.类依赖属性加权朴素贝叶斯(class-specific attribute weighted naïve Bayes,CAWNB)是一种有效的属性加权朴素贝叶斯算法.本文通过在条件对数似然(conditional log-likelihood,CLL)和均方差(mean squared error,MSE)目标函数中引入平衡系数λ,提出了两个新的目标函数λ-CLL和λ-MSE,并进一步提出了通过最大化λ-CLL或最小化λ-MSE确定最优权重值的两个不平衡数据分类算法CAWNB^(λ-CCL)和和CAWNB^(λ-MSE).在不平衡的UCI数据集上的实验表明,这样的属性加权可以增强朴素贝叶斯对于少数类的分类能力,同时不会过分破坏其的总体分类能力.

关键词：不平衡数据分类朴素贝叶斯属性加权

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