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DSAFF-Net:A Backbone Network Based on Mask R-CNN for Small Object Detection

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Computers, Materials & Continua 2023年第2期74卷 3405-3419页

作者： jian Peng Yifang Zhao Dengyong Zhang Feng li Arun Kumar Sangaiah Hunan Provincial Key Laboratory of Intelligent Processing of Big Data on Transportation Changsha University of Science and TechnologyChangsha410114China School of Computer and Communication Engineering Changsha University of Science and TechnologyChangsha410114China School of Computing Science and Engineering Vellore Institute of Technology(VIT)Vellore632014India

Recently,object detection based on convolutional neural networks(CNNs)has developed *** backbone networks for basic feature extraction are an important component of the whole detection ***,we present a new feature extraction strategy in this paper,which name is *** this strategy,we design:1)a sandwich attention feature fusion module(SAFF module).Its purpose is to enhance the semantic information of shallow features and resolution of deep features,which is beneficial to small object detection after feature fusion.2)to add a new stage called D-block to alleviate the disadvantages of decreasing spatial resolution when the pooling layer increases the receptive *** method proposed in the new stage replaces the original method of obtaining the P6 feature map and uses the result as the input of the regional proposal network(RPN).In the experimental phase,we use the new strategy to extract *** experiment takes the public dataset of Microsoft Common Objects in Context(MS COCO)object detection and the dataset of Corona Virus Disease 2019(COVID-19)image classification as the experimental object *** results show that the average recognition accuracy of COVID-19 in the classification dataset is improved to 98.163%,and small object detection in object detection tasks is improved by 4.0%.

关键词： Small object detection classification RPN MS COCO COVID-19

A nanosilica/exfoliated graphene composite film-modified electrode for sensitive detection of methyl parathion

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Chinese Chemical Letters 2016年第9期27卷 1541-1546页

作者： Ju Fu Xiao-Hong Tan Yao-Hua li Xin-jian Song Key Laboratory of Biologic Resources Protection and Utilization of Hubei Province Hubei University for Nationalities School of Chemical and Environmental Engineering Hubei University for Nationalities

Graphene nanosheets （GS） were easily prepared through liquid-phase exfoliation of graphite powder in N,N-dimethylformamide （DMF） with the assistance of sodium citrate. Then, GS was coated onto a glassy carbon electrode （GCE） surface by drop to fabricate a GS]GCE nanointerface. Subsequently, by using tetraethylorthosilicate sol as precursor, nanosilica was electrochemically deposited onto the GS]GCE surface to produce a nanocomposite film electrode （nanosilicaJGSJGCE）. Electrochemical behaviors of methyl parathion （MP） on the nanosilica/GS/GCE surface were investigated thoroughly. It was found that the nanosilicaJGS nanocomposites can improve the redox peak currents of MP significantly due to the synergetic effect. The oxidation peak current was linearly related to MP concentration in the range from 0.0005 μmol/L to 5.6 μmol/L. The detection limit was calculated to be 0.07 nmol/L （SJN = 3）. The developed method was used to determine MP in real samples. The recoveries were in the range from 95.4% to 104.2%, demonstrating satisfactory results.

关键词： Exfoliated graphene Nanosilica Modified electrodes Methyl parathion Electrochemical sensor

Synthesis and Crystal Structure of 3,3'-Dimethyl-dibenzo-18-crown-6

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Chinese Journal of Structural Chemistry 2006年第6期25卷 757-760页

作者： NIU Mei-Ju DOU jian-Min WANG Da-Qi li Da-Cheng Department of Chemistry Liaocheng University Liaocheng 252059 China

3,3′-Dimethyl-dibenzo-18-crown-6 was synthesized and characterized by elemental analysis, FT-IR, ^1H NMR, UV, MS spectra and X-ray single-crystal diffraction. It belongs to orthorhombic, space group Pna21 with a = 8.0790（18）, b = 16.780（4）, c = 15.222（3） .A, Z= 4, V= 2063.6（8） A3 Dc = 1.250 g/cm^3,μ = 0.090 mm^-1, F（000） = 832, R = 0.0474 and wR = 0.1103. According to structural analysis, the title compound possesses a boat-like configuration.

关键词： crown ether 3,3'-dimethyl-dibenzo-18-crown-6 synthesis crystal structure

Surface charge characteristics in a three-electrode surface dielectric barrier discharge

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Plasma Science and Technology 2024年第11期26卷 127-137页

作者： Jingwen FAN Huijie YAN Ting li Yurong MAO Jiaqi li jian SONGKey Laboratory of Materials Modification by Laser Ionand Electron BeamsMinistry of EducationSchool of PhysicsDalian 116024People’s Republic of China

The surface charge characteristics in a three-electrode surface dielectric barrier discharge(SDBD)are experimentally investigated based on the Pockels effect of an electro-optical crystal. The actuator is based on the most commonly used SDBD structure for airflow control, with an exposed electrode supplied with sinusoidal AC high voltage, a grounded encapsulated electrode and an additional exposed electrode downstream supplied with DC voltage. The ionic wind velocity and thrust can be significantly improved by increasing DC voltage although the plasma discharge characteristics are virtually unaffected. It is found that the negative charges generated by the discharge of the three-electrode structure accumulate on the dielectric surface significantly further downstream in an AC period compared to the actuator with a two-electrode structure. The negative charges in the downstream region increase as the DC voltage *** addition, the DC voltage affects the time required for the positive charge filaments to *** positive DC voltage expands the ionic acceleration zone downstream to produce a greater EHD force. The amplitude of the DC voltage affects the electric field on the dielectric surface and is therefore a key factor in the formation of the EHD force. Further research on the surface charge characteristics of a three-electrode structure has been conducted using a pulse power to drive the discharge, and the same conclusions are drawn. This work demonstrates a link between surface charge characteristics and EHD performance of a three-electrode SDBD actuator.

关键词： surface dielectric barrier discharge three-electrode structure electro-optical crystal surface charge

Erythropoietin reduces apoptosis of brain tissue cells in rats after cerebral ischemia/reperfusion injury:a characteristic analysis using magnetic resonance imaging

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Neural Regeneration Research 2016年第9期11卷 1450-1455页

作者： Chun-juan jiang zhong-juan Wang Yan-jun Zhao Zhui-yang Zhang Jing-jing Tao jian-yong Ma Department of Radiology Wuxi Second People's Hospital Affiliated to Nanjing Medical University

Some in vitro experiments have shown that erythropoietin （EPO） increases resistance to apoptosis and facilitates neuronal survival follow- ing cerebral ischemia. However, results from in vivo studies are rarely reported. Perfusion-weighted imaging （PWI） and diffusion-weighted imaging （DWI） have been applied successfully to distinguish acute cerebral ischemic necrosis and penumbra in living animals; therefore, we hypothesized that PWI and DWI could be used to provide imaging evidence in vivo for the conclusion that EPO could reduce apoptosis in brain areas injured by cerebral ischemia/reperfusion. To validate this hypothesis, we established a rat model of focal cerebral ischemia/ reperfusion injury, and treated with intra-cerebroventricular injection of EPO （5,000 U/kg） 20 minutes before injury. Brain tissue in the ischemic injury zone was sampled using MRI-guided localization. The relative area of abnormal tissue, changes in PWI and DWI in the ischemic injury zone, and the number of apoptotic cells based on TdT-mediated dUTP-biotin nick end-labeling （TUNEL） were assessed. Our findings demonstrate that EPO reduces the relative area of abnormally high signal in PWI and DWI, increases cerebral blood volume, and decreases the number of apoptotic cells positive for TUNEL in the area injured by cerebral ischemia/reperfusion. The experiment pro- vides imaging evidence in vivo for EPO treating cerebral ischemia/reperfusion injury.

关键词： nerve regeneration nerve protection cerebral ischemia/reperfusion erythropoietin magnetic resonance imaging diffusion-weightedimaging apparent diffusion coefficient perfusion-weighted imaging cerebral blood volume mean transit time apoptosis neural regeneration

Numerical Discretization-Based Kernel Type Estimation Methods for Ordinary Differential Equation Models

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Acta Mathematica Sinica,English Series 2015年第8期31卷 1233-1254页

作者： Tao HU Yan Ping QIU Heng jian CUI li Hong CHEN School of Mathematical Sciences & BCMIIS Capital Normal University School of Mathematical Sciences Beijing Normal University Fujian College of Water Conservancy and Eletric Power

We consider the problem of parameter estimation in both linear and nonlinear ordinary differential equation（ODE） models. Nonlinear ODE models are widely used in applications. But their analytic solutions are usually not available. Thus regular methods usually depend on repetitive use of numerical solutions which bring huge computational cost. We proposed a new two-stage approach which includes a smoothing method（kernel smoothing or local polynomial fitting） in the first stage, and a numerical discretization method（Eulers discretization method, the trapezoidal discretization method,or the Runge–Kutta discretization method） in the second stage. Through numerical simulations, we find the proposed method gains a proper balance between estimation accuracy and computational *** properties are also presented, which show the consistency and asymptotic normality of estimators under some mild conditions. The proposed method is compared to existing methods in term of accuracy and computational cost. The simulation results show that the estimators with local linear smoothing in the first stage and trapezoidal discretization in the second stage have the lowest average relative errors. We apply the proposed method to HIV dynamics data to illustrate the practicability of the estimator.

关键词： Nonparametric regression kernel smoothing local polynomial fitting parametric identification ordinary differential equation nume

The NAC transcription factor LuNAC61 negatively regulates fiber development in flax (linum usitatissimum L.)

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Journal of Integrative Agriculture 2024年第3期23卷 795-805页

作者： Dongwei Xie Jing li Wan li lijun Sun Zhigang Dai Wenzhi Zhou jianguang Su jian Sun School of life Sciences Nantong UniversityNantong 226019China Institute of Crop Cultivation and Tillage Heilongjiang Academy of Agricultural SciencesHarbin 150086China Institute of Bast Fiber Crops Chinese Academy of Agricultural SciencesChangsha 410221China jiangsu Sanshu Biotechnology Co.Ltd. Nantong 226001China

Flax is a crucial fiber crop that exhibits excellent textile properties and serves as a model plant for investigating phloem fiber development. The regulation of multiple genes significantly influences fiber development, notably involving NAC(NAM, ATAF1/2, CUC2) transcription factors in forming the fiber secondary cell wall(SCW).Overexpression of LuNAC61 in flax resulted in sparse top meristematic zone leaves and significantly reduced stem cellulose content. Scanning electron microscopy and staining observations revealed a significant reduction in fiber bundles. β-Glucuronidase(GUS) staining analysis demonstrated high activity of the LuNAC61 promoter in the bast fibers of the flax stem. Additionally, several members of the LuPLATZ and LuCesA families exhibited significant coexpression with LuNAC61. Subcellular localization indicated the presence of LuPLATZ24 protein in the nucleus and cytoplasm, LuNAC61 protein exclusively in the nucleus, and LuCesA10 in the nucleus and endoplasmic reticulum. LuPLATZ24 positively regulates LuNAC61, whereas LuNAC61 negatively affects LuCesA10, suggesting the involvement of a metabolic network in regulating flax fiber development. In conclusion, this study provides a critical opportunity for a comprehensive and in-depth analysis of the mechanisms governing flax fiber development and the potential use of biotechnology to enhance flax fiber yield.

关键词： flax fiber development Lu NAC61 gene function gene interaction

Expression profiles of Cry1Ab protein and its insecticidal efficacy against the invasive fall armyworm for Chinese domestic GM maize DBN9936

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Journal of Integrative Agriculture 2021年第3期20卷 792-803页

作者： liANG Jin-gang ZHANG Dan-dan li Dong-yang ZHAO Sheng-yuan WANG Chen-yao XIAO Yu-tao XU Dong YANG Yi-zhong li Guo-ping WANG li-li GAO Yu YANG Xue-qing YUAN Hai-bin liU jian ZHANG Xiu-jie WU Kong-ming Development Center of Science and Technology Ministry of Agriculture and Rural AffairsBeijing 100176P.R.China State Key Laboratory for Biology of Plant Diseases and Insect Pests Institute of Plant ProtectionChinese Academy of Agricultural SciencesBeijing 100193P.R.China State Key Laboratory of Cotton Biology Institute of Cotton ResearchChinese Academy of Agricultural SciencesAnyang 455000P.R.China Shenzhen Branch Guangdong Laboratory for Lingnan Modern AgricultureGenome Analysis Laboratory of the Ministry of AgricultureAgricultural Genomics Institute at ShenzhenChinese Academy of Agricultural SciencesShenzhen 518120P.R.China Institute of Plant Protection and Soil Science Hubei Academy of Agricultural SciencesWuhan 430064P.R.China College of Horticulture and Plant Protection Yangzhou UniversityYangzhou 225009P.R.China Institute of Plant Protection Henan Academy of Agricultural SciencesZhengzhou 450002P.R.China Yantai Academy of Agricultural Sciences Yantai 265500P.R.China College of Plant Protection Shenyang Agricultural UniversityShenyang 110866P.R.China College of Plant Protection Jilin Agricultural UniversityChangchun 130118P.R.China College of Agriculture Northeast Agricultural UniversityHarbin 150030P.R.China

The fall armyworm(FAW)Spodoptera frugiperda,which originated in the Americas,is advancing across China and threatening the nation’s maize ***,one widely used tool for its control is genetically modified(GM)Bacillus thuringiensis(Bt)*** content of Bt protein in appropriate plant parts is crucial for enhancing resistance against insect *** this study,we conducted a systematic investigation of Cry1 Ab levels in Chinese domestic GM maize DBN9936,which has recently obtained a biosafety certificate,and evaluated its efficacy against *** of expression levels of Cry1 Ab,via EliSA,indicated a spatio-temporal dynamic,with significant variation of mean Cry1 Ab,ranging from 0.76 to 8.48μg g-1 FW with the Cry1 Ab protein level ranked as:V6-V8 leaf>R1 leaf>R4 leaf>R1 silk>VT tassel>R4 *** the nine locations,the Cry1 Ab levels in DBN9936 of the Xinxiang,Langfang,and Harbin fields were significantly lower than those from Wuhan and Shenyang,and were slightly,but not significantly lower than those from the other four ***,the artificial diet-Cry1 Ab mixture and plant tissue feeding bioassays revealed that DBN9936 has high efficacy against *** insecticidal efficacy of different tissues against FAW larvae reached 34-100%with a descending order of lethality as follows:VT leaf>R4 leaf>R1 husk>R1 silk>VT tassel>R4 *** together,our results showed that Bt-Cry1 Ab maize DBN9936 has potential as a promising strategy to manage FAW.

关键词： fall armyworm genetically modified maize DBN9936 Cry1Ab expression control efficacy

“Early China:the Formative Period of Chinese Civilization” Displayed in Capital Museum

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China & The World Cultural Exchange 2010年第1期76卷 18-21页

作者： jian zhong

Last autumn, the exhibition "Early China: the Formative Period of Chinese Civilization" was held in the Capital Museum in Beijing. The 210 sets or pieces of exhibits showcase the origin and early evolution of Chinese ... 详细信息

关键词：首都博物馆中华文明早期演化形成时期中国形成期