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Journal of Environmental Sciences 2019年第5期31卷 239-247页

作者： Huai Li Zifang Chi Baixing Yan Key Laboratory of Wetland Ecology and Environment Northeast Institute of Geography and Agroecology Chinese Academy of Sciences Key Laboratory of Groundwater Resources and Environment Ministry of Education Jilin University

The increasing application of engineered nanoparticles(NPs) has posed an emerging challenge to constructed wetland wastewater treatment. The performance, microbial community and toxic mechanism of anammox-based unplanted subsurface-flow constructed wetlands(USFCWs) were investigated under the long-term exposure of different graphene oxides(GOs) and Ag NP concentrations. Results showed that the addition of GO could promote TN removal, manifesting as function anammox bacteria C. Anammoxoglobus having a relative high abundance, for GO did not cause significant damage to the cell integrity though there was an increase in ROS concentrations. TN removal would not be obviously affected under exposure of 1 mg/L Ag NPs, for the function gene related to cell biogenesis and repair was up-regulated; while the addition of 10 mg/L Ag NPs would have an inhibiting effect on TN removal in the USFCWs, for the disappearance of some species having anammox ability. Key enzymes of anammox process(NIR and HDH) decreased to some extent under GO and Ag NP exposure, and function gene of defense mechanisms had an increase trend in samples.

关键词： Anammox Ag NPs GO Microbial community Function gene Key enzymes

Aging-independent and size-dependent genotoxic response induced by titanium dioxide nanoparticles in mammalian cells

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Journal of Environmental Sciences 2019年第11期31卷 94-106页

作者： Juan Wang Jingjing Wang Yun Liu Yaguang Nie Bo Si Tong Wang Ahmed Waqas Guoping Zhao Meimei Wang An Xu Key Laboratory of High Magnetic Field and Ion Beam Physical Biology Chinese Academy of Sciences Anhui Province Key Laboratory of Environmental Toxicology and Pollution Control Technology Hefei Institutes of Physical Science Chinese Academy of Sciences Hefei Anhui 230031 P.R.China University of Science and Technology of China Hefei Anhui 230026 P.R.China Department of Pathophysiology Anhui Medical University Hefei Anhui 230032 P.R.China Institutes of Physical Science and Information Technology Anhui University Hefei Anhui 230601 P.R.China

Titanium dioxide nanoparticles (TiO2 NPs) are subjected to various transformation processes (chemical,physical and biological processes) in the environment,potentially affecting their bioavailability and toxic properties.However,the size variation of TiO2 NPs during aging process and subsequent effects in mammalian cells are largely unknown.The aim of this study was to illustrate the adverse effects of TiO2 NPs in different sizes (5,15 and NPs stock suspensions.The cytotoxicity of fresh TiO2 NPs increased in a size-dependent manner;in contrast,their genotoxicity decreased with the increasing sizes of NPs.No significant toxicity difference was observed in cells exposed to either fresh or 60 day-aged TiO2 NPs.Both Fresh and aged TiO2 NPs efficiently induced mitochondrial dysfunction and activated Caspase-3/7 in a size-dependent manner.Using mitochondrial-DNA deficient (ρ°) AL cells,we further discovered that mitochondrial dysfunction made significant contribution to the size-dependent toxicity induced by TiO2 NPs during the aging process.Taken together,our data indicated that TiO2 NPs could significantly induced the cytotoxicity and genotoxicity in an aging time-independent and size-dependent manner,which were triggered by mitochondrial dysfunction.Our study suggested the necessity to include size as an additional parameter for the cautious monitoring of TiO2 NPs disposal before entering the environment.

关键词： TiO2 NPs Aging process Human-hamster hybrid (AL) cells Mitochondria Size-effects

Neuronal and peripheral damages induced by synthetic psychoactive substances: an update of recent findings from human and animal studies

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Neural Regeneration Research 2020年第5期15卷 802-816页

作者： Giulia Costa Maria Antonietta De Luca Gessica Piras Jacopo Marongiu Liana Fattore Nicola Simola Department of Biomedical Sciences University of CagliariCagliariItaly National Institute of Neuroscience (INN) University of CagliariCagliariItaly National Research Council of Italy Institute of NeuroscienceCagliariItaly

Preclinical and clinical studies indicate that synthetic psychoactive substances,in addition to having abuse potential,may elicit toxic effects of varying severity at the peripheral and central levels.Nowadays,toxicity induced by synthetic psychoactive substances poses a serious harm for health,since recreational use of these substances is on the rise among young and adult people.The present review summarizes recent findings on the peripheral and central toxicity elicited by “old” and “new” synthetic psychoactive substances in humans and experimental animals,focusing on amphetamine derivatives,hallucinogen and dissociative drugs and synthetic cannabinoids.

关键词： cannabinoids dissociatives hallucinogens ketamine MDMA methamphetamine methoxetamine neuroinflammation neurotoxicity NPs

Genetic mining of the “dark matter” in fungal natural products

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Science China(Life Sciences) 2019年第9期62卷 1250-1252页

作者： Wei Li Wen-Bing Yin State Key Laboratory of Mycology Institute of MicrobiologyChinese Academy of SciencesBeijing 100101China Savaid Medical School University of Chinese Academy of SciencesBeijing 100049China

Filamentous fungi are one of the major sources of natural products (NPs;which are also termed as secondary metabolites (SMs)) with diverse biological activities,which have been widely used in agriculture,industry,and pharmaceuticals.Fungi are the second largest species in nature,and their biodiversity implies genomic diversity,which,in turn,predicts the structural diversity of metabolites.In general,NPs can be classified as polyketides (PKs),nonribosomal peptides (NRPs),hybrid PK-NRPs,or terpenoids according to the types of their biosynthetic skeleton enzymes.These enzymes include polyketide synthases (PKSs),nonribosomal peptide synthetases (NRPSs),hybrid polyketide synthasenonribosomal peptide synthetases (PKS-NRPSs),and terpene synthases or terpene cyclases (TCs).A hallmark in fungal NP biosynthesis is that the relevant genes are usually arranged close to each other on the chromosome in what is called a biosynthetic gene cluster (BGC).Over 2,200 fungal genome sequences are publicly available because of the rapid development of genome sequencing technology and the launch of 1000 Fungal Genome Project by the Joint Genome Institute (JGI).Bioinformatics analyses confirm that the fungal genome has an abundance of BGCs.An NP “dark matter” treasure may be present in the fungal genome as over 90% of BGCs are unexplored,silent,or cryptic (He et al.,2018;Keller,2019).These data provide us an opportunity to search for fungal NPs using gene/genome as the starting point.

关键词： skeleton cluster Project NPs can has be is

静电纺丝基碳纤维载纳米钯催化剂的制备及应用

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无机材料学报 2014年第8期29卷 814-820页

作者：郭丽萍白杰梁海欧李春萍孙炜岩孟庆润内蒙古工业大学化工学院呼和浩特010051

采用静电纺丝、化学还原及高温碳化方法制备了碳纳米纤维螯合钯纳米粒子复合催化剂。实验详细考察了三种还原剂(硼氢化钠、水合肼、氢气)在催化剂制备过程中对钯纳米粒子及碳纤维形貌的影响。通过固体紫外、X射线粉末衍射、红外、扫描... 详细信息

采用静电纺丝、化学还原及高温碳化方法制备了碳纳米纤维螯合钯纳米粒子复合催化剂。实验详细考察了三种还原剂(硼氢化钠、水合肼、氢气)在催化剂制备过程中对钯纳米粒子及碳纤维形貌的影响。通过固体紫外、X射线粉末衍射、红外、扫描电镜、场发射透射电镜等测试方法对已制备的一系列催化剂进行表征。结果表明选择氢气为还原剂时,碳纤维上获得了7 nm左右、粒子分布均匀的钯纳米粒子,催化剂相对柔韧,继而将此催化剂应用于Heck偶联反应测试其催化及循环利用特性。催化结果证实此方法制备的催化剂具有优异的稳定性、底物耐受性、可回收性。

关键词：静电纺丝钯纳米粒子 Pd NPs CNFs Heck反应

Insight into the preformed albumin corona on in vitro and in vivo performances of albumin-selective nanoparticles

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Asian Journal of Pharmaceutical Sciences 2019年第1期14卷 52-62页

作者： Zhenbao Li Dan Li Wenjuan Zhang Peng Zhang Qiming Kan Jin Sun Wuya College of Innovation Shenyang Pharmaceutical UniversityWenhua RoadShenyang 110016China The College of Pharmacy Anhui University of Chinese MedicineHefei 230012China Department of Pharmacy Shenyang Pharmaceutical UniversityChina Department of Pharmacology Shenyang Pharmaceutical UniversityNo.103 Wenhua RoadShenyang 110016China

Preformed albumin corona of albumin-nonselective nanoparticles(NPs)is widely exploited to inhibit the unavoidable protein adsorption upon intravenous administration.However,very few studies have concerned the preformed albumin corona of albumin-selective NPs.Herein,we report a novel type of albumin-selective NPs by decorating 6-maleimidocaproyl polyethylene glycol stearate(SA)onto PLGA NPs(SP NPs)surface,taking albuminnonselective PLGA NPs as control.PLGA NPs and SP NPs were prepared by emulsion-solvent evaporation method and the resultant NPs were in spherical shape with an average diameter around 180 nm.The corresponding albumin-coating PLGA NPs(PLGA@BSA NPs)and albumin-coating SP NPs(SP@BSA NPs)were formulated by incubating SP NPs or PLGA NPs with bovine serum albumin solution,respectively.The impact of albumin corona on particle characteristics,stability,photothermal effect,cytotoxicity,cell uptake,spheroid penetration and pharmacokinetics was investigated.In line with previous findings of preformed albumin coating,PLGA@BSA NPs exhibited higher stability,cytotoxicity,cell internalization and spheroid penetration performances in vitro,and longer blood circulation time in vivo than those of albumin-nonselective PLGA NPs,but albumin-selective SP NPs is capable of achieving a comparable in vitro and in vivo performances with both SP@BSA NPs and PLGA@BSA NPs.Our results demonstrate that SA decorated albumin-selective NPs pave a versatile avenue for optimizing nanoparticulate delivery without preformed albumin corona.

关键词： Preformed albumin corona Albumin-nonselective PLGA NPs Albumin-selective SP NPs In vitro and in vivo performances

The Research of Customer Loyalty Improvement in Telecom Industry Based on NPs Data Mining

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China Communications 2017年第11期14卷 260-268页

作者： Lili Tong Yiting Wang Fan Wen Xiaowen Li Beijing University of Posts and Telecommunications Beijing 100876 China School of Economics and Management Beijing University of Posts and Telecommunications Beijing 100876 China School of Computer Science Beijing University of Posts and Telecommunications Beijing 100876 China China Mobile Communications Co. Ltd. Enterprise Customer Branch Beijing 100032 China

In recent years, the telecommunications have used the concept of NPs(Net Promoter Score) for customer relationship management, but there is neither definite theory research nor instructive instance research. However, this paper summarizes an approach with instance case analysis to improve customer loyalty via NPs data mining, which has extensive and practical significance for tele-companies. First, this paper finds some driven forces of customer loyalty, which are relative to customer consumption such as the call duration, the usage of data, ARPU, etc., by using some innovative reasoning-analysis based on IG(Information Gain) and xg-boost decision-making tree model, so the tele-companies can predict the role of individual customer and form daily monitoring on big data, which will save a lot of NPs survey cost. Second, this paper summarizes how customer group feature impacts the relationship between NPs and financial performance. Taking ARPU value as the performance goals, we divide the sample customers into 6 groups and summarize their characteristics based on k-means clustering, and give targeted suggestion of each group.

关键词： net promoter NPs customer loyalty data mining

亲水性FePt纳米颗粒协同催化有机污染物的降解

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高等学校化学学报 2020年第4期41卷 697-705页

作者：刘丛远刘佳杜佩瑶张振卢小泉天津市分子光电科学重点实验室天津大学理学院化学系天津300072

以半胱氨酸为配体,采用一锅法简便合成了亲水性的FePt纳米颗粒(NPs).超小的FePt NPs对水中常见有机污染物表现出良好的催化降解性能,以NaBH 4为还原剂时可实现对染料罗丹明B(RhB)和有害物质4-硝基苯酚(4-NP)的有效还原;以H 2O 2为氧化... 详细信息

以半胱氨酸为配体,采用一锅法简便合成了亲水性的FePt纳米颗粒(NPs).超小的FePt NPs对水中常见有机污染物表现出良好的催化降解性能,以NaBH 4为还原剂时可实现对染料罗丹明B(RhB)和有害物质4-硝基苯酚(4-NP)的有效还原;以H 2O 2为氧化剂时可实现亚甲基蓝(MB)的高效降解.实验结果表明,FePt NPs对3种有机污染物的降解率均高于90%.对FePt原子对之间的协同催化机理进行了探讨,揭示了不同反应体系中微观反应历程和催化机理的区别.磁性测试结果表明,FePt催化剂可以通过外加磁场进行收集并重复利用,解决了催化剂二次污染问题.该研究为设计合成绿色环保催化剂提供了思路.

关键词：亲水性FePt NPs 协同催化有机污染物降解可回收

Up-conversion fluorescence biosensor for sensitive detection of CA-125 tumor markers

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Journal of Rare Earths 2019年第9期37卷 943-948,I0002页

作者： Jingshi Liu Sai Xu Liheng Sun Songtao Hu Jiao Sun Min Liu Cui Ma Haipeng Liu Ziqing Wang Ying Yang Biao Dong Decheng Hong College of Physics Jilin UniversityChangchun 130021China State Key Laboratory on Integrated Optoelectronics College o f Electronic Science and EngineeringJilin UniversityChangchun 130012China Department of Physics Dalian Maritime UniversityDalian 116026China Department of Cell Biology College of Basic Medical SciencesJilin UniversityChangchun 130021China Department of Radiation Oncology. The First Hospital Jilin UniversityChangchun 130021China

Sensitive and specific bioassays of tumor markers are critical for early cancer detection and treatment.In recent years,lanthanide(Ln3+)doped upconversion nanoparticles(UCNPs)have attracted wide attentions in tumor markers detectio n.Herein,we co mbined NaYF4:Yb,Tm and silver nanoparticles,serving as energy donor and receptor,respectively,to form an up-conversion fluorescence based inhibitory tumor marker biosensor system.The tumor marker CA-125 molecules are labeled with silver NPs,and the energy transfer fluorescent signal can be detected between the UCNPs and the silver NP receptors.The biosensor shows good stability,high sensitivity and selectivity in the tumor marker concentration range from 5 to 100 ng/mL,as well as a detection limit of 120 pg/mL.Due to the advantage of ease of fabrication and operation,low cost and high information capacity,this technology holds great potential for the clinical applications.

关键词： NaYF4:Yb,Tm CA-125 molecules Silver NPs Energy transfer Good stability High sensitivity and selectivity

A公司在线学习APP客户满意度提升策略研究

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A公司在线学习APP客户满意度提升策略研究

作者：李俊广西师范大学

学位级别：硕士

2020年底国家“十四五”规划提出要充分利用在线教育的优势,推动学习型社会的建设。在疫情期间,中国有将近两亿的中小学生面临不得不停课在家学习,各家在线教育机构纷纷推出形式多样的免费直播课,使得沉寂了十多年的互联网在线教育迎来... 详细信息

2020年底国家“十四五”规划提出要充分利用在线教育的优势,推动学习型社会的建设。在疫情期间,中国有将近两亿的中小学生面临不得不停课在家学习,各家在线教育机构纷纷推出形式多样的免费直播课,使得沉寂了十多年的互联网在线教育迎来了井喷式爆发。但好景不长,2021年第三季度,国家正式落地了关于减轻义务教育学龄学生校内和校外学业负担的“双减”政策,让疯狂“烧钱”发展的互联网在线教育正式进入了调整期,各互联网教育公司不得不一边配合政策对相关业务进行整改,一边寻找新的转型出路。对于互联网在线教育产品客户满意度,一直是困扰各教育机构市场营销的重要致命因素,客户满意度也最终影响到互联网在线教育公司,如何在激烈的竞争中持续发展经营下去。本论文以A公司的在线学习APP产品为例,研究双减背景下初中生客户对该产品的满意度的提升策略。通过使用定性与定量相结合的分析方法,对A公司整个APP端内产品满意度情况进行分析与论证,旨在准确地获得初中学生客户对A公司在线学习产品和服务的态度及成因,有针对性地为初中学生客户提供各种差异化、个性化的服务,提高初中学生客户的满意度,让A公司原本就有的注册客户可以在端内活跃使用,让通过各流量渠道引流来的新客户能够快速转化成为忠诚的活跃客户,在流量如此昂贵的今天,让A公司得以在激烈的竞争中胜出。本研究在当前教育“双减”政策的背景下,调查了A公司在线学习APP的发展现状,发现该APP正在面临着用户观望情绪较大,延迟购买且数量下降的问题。针对该问题,本文研究如何提高当前客户的满意度以期达到保留客户的目的。本文在现有客户满意度研究理论和模型的基础上,结合该在线学习APP产品的特点,设计了针对该在线学习APP产品客户满意度的评价指标,采用问卷调查的方式,收集了230份初中生客户的样本数据,利用SPSS 26.0软件、Spsspro在线统计分析软件进行分析和处理,采用主成分因子分析法获得影响客户满意度的三个主要因子,针对这三个因子分析该在线学习APP在客户满意度这方面存在的问题并分析了问题的成因。在问题和成因的基础上,本文分别针对这三个因子,从客户体验维度提出增加学习互动感、提高学习趣味性的提升策略,从功能维度提出优化界面丰富功能的提升策略,从课程维度提出结合教材更新和优化课程的提升策略,以期进一步改善该在线学习APP的客户满意度,从而达到保留客户的目的。

关键词：在线学习客户满意度影响因素 NPs