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Particuology 2020年第3期18卷 189-196页

作者： Nishan K.Shah Ryan Ivone jie shen Samantha A.Meenach University of Rhode Island College of PharmacyDepartment of Biomedical and Pharmaceutical SciencesKingstonRI 02881USA University of Rhode Island College of EngineeringDepartment of Chemical EngineeringKingstonRI 02881USA

Tangential fiow filtration (TFF) is a purification method commonly used in a multitude of fields,including particle ***,there is still a lack of comprehensive understanding of the effects of key TFF parameters on nanoparticle (NP) characteristics (purification outcomes).The present study aimed to investigate the influence of various factors on the characteristics of TFF-purified *** most commonly used NP purification method,centrifugation,was studied as a control.A design of experiment approach was implemented to investigate the influence of transmembrane pressure,flow rate,and initial drug loading on NP characteristics using paclitaxel as a model small *** the determination of optimized TFF parameters,the two purification methods were assessed using other model small molecules (*** and resveratrol).The results indicated that the TFF parameters and initial loading of the drug played important roles in the purified NP *** with the centrifugation method,TFF resulted in smaller NP with higher drug *** was able to circumvent issues associated with conventional centrifugation,while yielding similar results,and can potentially serve as a suitable large-scale purification method for polymeric NP.

关键词： Tangential flow filtration Nanoparticle purification Box-Behnken design Acetalated dextran Drug delivery

Sphericity and Identity Test for High-dimensional Covariance Matrix Using Random Matrix Theory

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Acta Mathematicae Applicatae Sinica 2021年第2期37卷 214-231页

作者： Shou-cheng YUAN jie ZHOU Jian-xin PAN jie-qiong shen College of Mathematics Sichuan UniversityChengdu 610064China School of Mathematics University of ManchesterManchester M139PLUK School of Computer and Data Engineering Zhejiang University Ningbo Institute of TechnologyNingbo 315100China

This paper addresses the issue of testing sphericity and identity of high-dimensional population covariance matrix when the data dimension exceeds the sample *** central limit theorem of the first four moments of eigenvalues of sample covariance matrix is derived using random matrix theory for generally distributed ***,some desirable asymptotic properties of the proposed test statistics are provided under the null hypothesis as data dimension and sample size both tend to *** show that the proposed tests have a greater power than existing methods for the spiked covariance model.

关键词： sphericity test identity test high-dimensional covariance matrix spiked model spectral distribution

基于虚拟仿真平台的婴幼儿托育服务与管理专业学习者画像构建

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卫生职业教育 2025年第1期43卷 119-122页

作者：刘纪元申洁张宜佳鹤壁职业技术学院河南鹤壁458030

目的构建婴幼儿托育服务与管理专业学习者画像,挖掘该专业学生线上学习特点,以达到线上教学质量持续提高的目的。方法将我院140名学生的虚拟仿真学习行为数据进行归一化处理,采用K-means聚类算法对数据进行聚类分析,并对不同类型学习者... 详细信息

目的构建婴幼儿托育服务与管理专业学习者画像,挖掘该专业学生线上学习特点,以达到线上教学质量持续提高的目的。方法将我院140名学生的虚拟仿真学习行为数据进行归一化处理,采用K-means聚类算法对数据进行聚类分析,并对不同类型学习者学习行为进行分析。结果形成高投入型学习者、中投入型学习者、低投入型学习者3类学习者。不同类型学习者在任务点完成进度、试题完成进度、平台使用时长、试题练习时长、回答问题次数、参与讨论次数方面比较有明显差异。投入度高的学生期末成绩明显较好;试题练习时长、试题完成进度、平台使用时长显著影响学生期末成绩。结论虚拟仿真教学中不同类型学习者特征存在差异,并显著影响学习效果。建议开发更多针对婴幼儿托育服务与管理专业的虚拟仿真教学资源,并提升学生在实训中的参与度。

关键词：虚拟仿真婴幼儿托育服务与管理专业学习者画像

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An AIE Star Polymer with Enhanced Co-Delivery of Drug and Gene for Synergistic Pest Control

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Chinese Journal of Chemistry 2023年第20期41卷 2671-2678页

作者： Bingcheng Zhou Qinhong Jiang jie Li Shuo Yan jie shen Lianying Liu Meizhen Yin State Key Laboratory of Chemical Resource Engineering Beijing Lab of Biomedical MaterialsBeijing University of Chemical TechnologyBeijing100029 China Department of Plant Biosecurity and MARA Key Laboratory of Surveillance and Management for Plant Quarantine Pests College of Plant ProtectionChina Agricultural UniversityBeijing100193 China

Pesticides,as the most common means of pest managements,have caused a series of problems such as pest resistance and environmental ***-induced emission(AIE)polymers exhibit great potential in biological applications because their fluorescent intensities significantly enhance in the aggregated *** this paper,an AIE star polymer including a tetraphenyl ethylene(TPE)core and poly(2-(dimethylamino)ethyl methacrylate)arms is designed and further developed as a multi-functional nanocarrier for agricultural pest *** nanocarrier shows high water solubility,good size stability and AIE imaging ***,the twisted AIE core and positively charged polymer arms make the nanocarrier efficiently co-load dinotefuran(DIN)and dsRNA via hydrogen bonds and electrostatic interactions,*** AIE star polymer displays low toxicity and high fluorescence *** a result,the nanocarrier co-loading with DIN and dsRNA exhibits a highly synergistic insecticidal effect with higher pest mortality compared to the separate delivery of DIN and *** study develops the AIE star polymer to improve the efficiency of co-delivery of drug and dsRNA and proposes a new strategy toward efficient and synergistic pest control.

关键词： Pest control Nano-delivery system Drug nanocarrier Functional polymers Aggregation-induced emission

Identification of three kinds of Plumeria flowers by DNA barcoding and HPLC specific chromatogram

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Journal of Pharmaceutical Analysis 2018年第3期8卷 176-180页

作者： Leilei Zhao Xiaoxue Yu jie shen Xinjun Xu School of Pharmaceutical Sciences Sun Yat-sen University Guangzhou 510006 China Guangdong Technology Research Center for Advanced Chinese Medicine Guangzhou China

DNA barcoding and HPLC specific chromatogram were used to identify three kinds of Plumeria flowers respectively. DNAs extracted from the three Plumeria species were amplified by PCR with universal primers, and the psbA-trnH region was selected. All the amplified products were sequenced and the results were analyzed by MEGA 5.0. Chemometric methods including principal components analysis and hierarchical clustering analysis were conducted on the SAS 9.0 software to demonstrate the variability among samples. In conclusion, the psbA-trnH of all samples were successfully amplified from total DNA and sequenced. These three varieties of Plumeria can be differentiated by the psbA-trnH region and clustered into three groups respectively through building neighbor joining tree, which conformed to their germplasm origins. However, it was hard to distinguish them by HPLC specific chromatograms combined with chemometrics analysis. These indicated that DNA barcoding was a promising and reliable tool for the identification of three kinds of Plumeria flowers compared to HPLC specific chromatogram generally used. It could be treated as a powerful complementary method for traditional authentication, especially for those varieties which are difficult to be identified by conventional chromatography.

关键词： Plumeria DNA barcoding HPLC specific chromatogram Chemometrics analysis Identification

An MYB Transcription Factor from Malus xiaojinensis Has a Potential Role in Iron Nutrition

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Journal of Integrative Plant Biology 2008年第10期50卷 1300-1306页

作者： jie shen Xuefeng Xu Tianzhong Li Dongmei Cao ZhenhaiHan Institute for Horticultural Plants China Agricultural University Beijing 100094 China

Regulation of iron uptake and use is critical for plant survival and growth. We isolated an MYB gene from Malus xiaojinensis named MxMYB1, which is induced under Fe-deficient conditions. Expression of MxMYB1 was upregulated by Fe starvation in the roots but not in leaves, suggesting that MxMYB1 might play a role in iron nutrition in roots. Transgenic Arabidopsis plants expressing MxMYB1 exhibited lower iron content as compared with wild type plants under both Fe-normal （40 μM） and Fe-deficient conditions （Fe omitted and Ferrozine 300 μM）. However, the contents of Cu, Zn and Mn were not changed in these transgenic plants. Gene chip and real-time polymerase chain reaction analyses indicated that the expression of two Fe-related genes encoding an iron transporter AtlRT1 and an iron storage protein ferritin AtFER1 might be negatively regulated by MxMYB1 as the expression levels of these genes were lower in MxMYB1 expressing transgenic Arabidopsis plants as compared with wild type plants under both Fe-normal and Fe-deficient conditions. These results suggest that MxMYB1 may function as a negative regulator of iron uptake and storage in plants.

关键词： Fe Malus xiaojinensis MxMYB transgenic Arabidopsis.

Analysis of wave propagation in micro/nanobeam-like structures: A size-dependent model

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Acta Mechanica Sinica 2012年第6期28卷 1659-1667页

作者： Bing-Lei Wang Jun-Feng Zhao shen-jie Zhou Xi Chen Department of Engineering Mechanics Shandong University School of Mechanical Engineering Shandong University Department of Earth and Environmental Engineering Columbia University International Center for Applied Mechanics SV Lab School of Aerospace Xi'an Jiaotong University

By incorporating the strain gradient elasticity into the classical Bernoulli-Euler beam and Timoshenko beam models, the size-dependent characteristics of wave propaga- tion in micro/nanobeams is studied. The formulations of dis- persion relation are explicitly derived for both strain gradi- ent beam models, and presented for different material length scale parameters （MLSPs）. For both phenomenological size- dependent beam models, the angular frequency, phase veloc- ity and group velocity increase with increasing wave num- ber. However, the velocity ratios approach different values for different beam models, indicating an interesting behavior of the asymptotic velocity ratio. The present theory is also compared with the nonlocal continuum beam models.

关键词： Strain gradient elasticity theory ~ Bernoulli-Euler beam theory. Timoshenko beam theory Wave propa-gation

Cost Sensitive Multi-Class Fuzzy Decision-theoretic Rough Set Based Fault Diagnosis 36

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Cost Sensitive Multi-Class Fuzzy Decision-theoretic Rough Se...

Characteristics of Fengyun-4A Satellite Atmospheric Motion Vectors and Their Impacts on Data Assimilation

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作者： Li Wang jie shen Xue Mei School of Electrical Engineering and Control Science Nanjing Tech University

ISBN: (纸本)9781538629185

Cost-sensitive multi-class fuzzy decision-theoretic rough set（MCFDTRS） is proposed by considering cost sensitivity in practical fault diagnosis *** generalizes indiscernibility relation of multi-class decision-theoretic rough set to Gaussian kernel based fuzzy equivalence relation,and then it can deal with numerical data directly without *** introduces cost matrix for loss functions to solve classification problems where different types of misclassification have different ***,negative and boundary region classification rules are extracted from data based on Bayesian risk minimum *** method is applied to fault diagnosis of power transformer to validate the effectiveness of the proposed *** results on transformer fault diagnosis examples show that the proposed method is well suitable for cost-sensitive fault diagnosis tasks and leads to lower misdiagnosis cost.

关键词： multi-class fuzzy decision-theoretic rough set cost-sensitive misclassification cost fault diagnosis

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Advances in Atmospheric Sciences 2020年第11期37卷 1222-1238页

作者： Yaodeng CHEN jie shen Shuiyong FAN Deming MENG Cheng WANG Key Laboratory of Meteorological Disaster of Ministry of Education/Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science and TechnologyNanjing 210044China Institute of Urban Meteorology China Meteorological AdministrationBeijing 100089China

The high observation efficiency,scanning speed and observation frequency of the Fengyun-4A(FY-4A)satellite indicates the progress of Chinese geostationary meteorological *** characteristics of FY-4A atmospheric motion vectors(AMVs)derived from the high-level water vapor(WV-High)channel,mid-level water vapor(WV-Mid)channel,and infrared(IR)channel of FY-4A are analyzed,and their corresponding observation errors ***,the impacts of single-channel and multi-channel FY-4A AMVs on RMAPS-ST(the Rapid-refresh Multi-scale Analysis and Prediction System-Short Term)are evaluated based on one-month data assimilation cycling and forecasting *** show that the observation errors of FY-4A AMVs from the three channels have an explicit vertical *** from the cycling experiments indicate that the assimilation of AMVs from WV-High produces more apparent improvement of the wind in the upper layer,while a more positive effect in the lower layer is achieved by the assimilation of AMVs from ***,the assimilation of AMVs from IR is more skillful for medium and moderate precipitation than from other channels owing to the good quality of data in the lower layer in the AMVs from *** of FY-4A AMVs from the three channels could combine the advantages of assimilation from each individual channel to improve the wind in the upper,middle and lower layers simultaneously.

关键词： data assimilation FY-4A satellite atmospheric motion vector observation error

Targeting ferroptosis opens new avenues for the development of novel therapeutics

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Signal Transduction and Targeted Therapy 2023年第10期8卷 4716-4745页

作者： Shumin Sun jie shen Jianwei Jiang Fudi Wang Junxia Min The First Affiliated Hospital Institute of Translational MedicineThe Second Affiliated HospitalSchoolof Public HealthCancer CenterState Key Laboratory of Experimental HematologyZhejiang University School of MedicineHangzhouChina

Ferroptosis is an iron-dependent form of regulated cell death with distinct characteristics,including altered iron homeostasis,reduced defense against oxidative stress,and abnormal lipid *** studies have provided compelling evidence supporting the notion that ferroptosis plays a key pathogenic role in many diseases such as various cancer types,neurodegenerative disease,diseases involving tissue and/or organ injury,and inflammatory and infectious diseases.

关键词： peroxidation diseases homeostasis