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Genetic Variation Among the Geographic Population of the Grain Aphid, Sitobion avenae (Hemiptera: Aphididae) in China Inferred from Mitochondrial COI Gene Sequence

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Agricultural Sciences in China 2011年第7期10卷 1041-1048页

作者： XU Zhao-huan CHEN Ju-lian CHENG deng-fa LIU Yong frédéric francis College of Plant Protection Shandong Agricultural University Tai＇an 271018 P.R.China State Key Laboratory for Biology of Plant disease and Insect Pests Institute of Plant Protection Chinese Academy of Agricultural Sciences Beijing 100193 P.R.China Functional and Evolutionary Entomology Gembloux Agro-Bio Tech University of Liege Passage des Déportés 2 Gembloux B-5030 Belgium

In order to characterize the genetic relationship of the geographic populations of Sitobion avenae （Hemiptera： Aphididae） in China, a 588 bp region of the mitochondrial cytochrome oxidase subunit I （mtdNA-COI） gene was sequenced and analyzed among the different geographic populations. 269 individuals were collected from 17 localities in different wheat-growing areas in China that covered most of the range reported for this species. Within the sequence among these geographic populations, 15 polymorphic sites defined 16 distinct haplotypes, ranging in sequence divergence from 0.2% （one nucleotide） to 1.7% （10 nucleotides）. Of the 15 variable sites, 12 were transitional substitutions, 2 were transversional substitutions and 1 was transitional and transversional substitution. Phylogenetic analysis showed that all haplotypes were highly interconnected with each other, in absence of phylogeographic structing. Each of 8 haplotypes was found only at one locality, and the other haplotypes were the widespread distributed in the different localities. The higher genetic diversity was found in the northern China populations than that in the southern China populations. The low genetic differentiation （FST=-0.06945-0.69857） and high migration rate （Nm=0.21575-infinite） of Chinese populations suggest that dispersal over long distance is a major factor in the demography of S. avenae.

关键词： Sitobion avenae insect pest mitochondrial dNA mtdNA-COI gene geographic variation

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Population genetic structure of Sitobion miscanthi in China

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Journal of Integrative Agriculture 2022年第1期21卷 178-187页

作者： SUN Jing-xuan LI Qian TAN Xiao-ling FAN Jia ZHANG Yong QIN Yao-guo frédéric francis CHEN Ju-lian State Key Laboratory for Biology of Plant diseases and Insect Pests Institute of Plant ProtectionChinese Academy of Agricultural SciencesBeijing 100193P.R.China department of Functional and Evolutionary Entomology Gembloux Agro-Bio TechUniversity of LiègeGembloux 5030Belgium Mudanjiang Branch of Heilongjiang Academy of Agricultural Sciences Mudanjiang 157000P.R.China

The wheat aphid, Sitobion miscanthi, is one of the most destructive pests of wheat plants in the temperate regions of China. Little is known about the genetic structure evolution of the different geographic populations of S. miscanthi with its migration. In this study, we investigated the population genetic structure and demographic history of S. miscanthi by analysing 18 geographical populations across China using one mitochondrial gene, COI;one nuclear gene, EF-1α;and two endosymbiont Buchnera genes, gnd and trpA. Analysis of data from the various groups showed high haplotype diversity and low nucleotide variation. SAMOVA analysis did not find a correlation between genetic distance and geographic distance. However, areas with high population diversity exhibited high haplotype diversity. Therefore, we speculate that there are two main natural migration pathways of S. miscanthi in China. One is from Yunnan to the Sichuan Basin, and the other is from Wuhan, Xinyang and Jiaodong Peninsula areas to the northwest. Based on this hypothesis, we inferred that these aphid populations appear first in the southwestern and southern regions and spread to the north with the help of the southeastern and southwestern monsoons, which occur in spring and summer. In autumn, the aphids spread southward with the northeastern and northwestern monsoons.

关键词： Sitobion miscanthi molecular marker COI symbiotic bacteria phylogenetic tree

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Influence of Garlic Intercropping or Active Emitted Volatiles in Releasers on Aphid and Related Beneficial in Wheat Fields in China

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Journal of Integrative Agriculture 2013年第3期12卷 467-473页

作者： ZHOU Hai-bo CHEN Ju-lian LIU Yong frédéric francis Eric Haubruge Claude Bragard SUN Jing-rui CHENG deng-fa State Key Laboratory for Biology of Plant disease and Insect Pests Institute of Plant Protection Chinese Academy of Agricultural Sciences Functional and Evolutionary Entomology Gembloux Agro-Bio Tech University of Liege College of Plant Protection Shandong Agricultural University Université catholique de Louvain Earth & Life Institute Applied Microbiology-Phytopathology

In order to develop biological control of aphids by a ＂push-pull＂ approach, intercropping using repellent emitting plants was developed in different crop and associated plant models. Garlic is one of the potential plant that could be inserted in crops to decrease the pest occurrence in neighboring crop plots. In this study, field works were conducted in wheat fields in Langfang Experimental Station, Hebei Province in China from October 2009 to July 2010 during wheat developmental season. The effect of wheat intercropping with garlic but also the volatiles emission on the incidence of the English grain aphid, Sitobion avenae Fabricius （Homoptera： Aphididae） was assessed. Natural beneficial occurrence and global yields in two winter wheat varieties that were susceptible or resistant to cereal aphid were also determined comparing to control plots without the use of garlic plant intercrop nor semiochemical releaser in the fields. S. avenae was found to be lower in garlic oil blend treatment （GOB）, diallyl disulfide treatment （dd） and wheat-garlic intercropping treatment （WGI） when compared to the control plots for both two varieties （P〈0.01）. Both intercropping and application of volatile chemicals emitted by garlic could improve the population densities of natural enemies of cereal aphid, including ladybeetles and mummified aphids. Ladybeetle population density in WGI, GOB and mummified aphids densities in WGI, dd were significantly higher than those in control fields for both two varieties （P〈0.05）. There were significant interactions between cultivars and treatments to the population densities of S. avenae. The 1 000-grain weight and yield of wheat were also increased compared to the control. due to their potential alternatives as a biological control agent against cereal aphid, garlic intercropping and related emitted volatiles are expected to contribute to the further improvement of integrated pest management systems and to potentially reduce the amount of traditio

关键词： wheat garlic intercropping semiochemical release Sitobion avenae natural enemies

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手性农药丁氟螨酯对斑马鱼胚胎的选择性发育毒性

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环境科学学报 2021年第2期41卷 680-688页

作者：高腾飞李敏敏孔志强王瑞全蕊张嘉李瑞瑆叶丰 frédéric francis 王凤忠范蓓农业农村部农产品质量安全收贮运管控重点实验室/中国农业科学院农产品加工研究所北京100193 植物病虫害生物学国家重点实验室/中国农业科学院植物保护研究所北京100193 列日大学让布鲁农业生物技术学院让布鲁5030

近年来丁氟螨酯(CYF)对非靶标生物的发育毒性已成为一个值得关注的问题,但其对水生生物的对映选择性效应尚不清晰.为评估丁氟螨酯对斑马鱼胚胎的对映选择性毒性,通过96 h的暴露试验,研究了梯度浓度的丁氟螨酯消旋体及对映体对斑马鱼胚... 详细信息

近年来丁氟螨酯(CYF)对非靶标生物的发育毒性已成为一个值得关注的问题,但其对水生生物的对映选择性效应尚不清晰.为评估丁氟螨酯对斑马鱼胚胎的对映选择性毒性,通过96 h的暴露试验,研究了梯度浓度的丁氟螨酯消旋体及对映体对斑马鱼胚胎的急性毒性.此外,试验还研究了丁氟螨酯对斑马鱼胚胎孵化率、卵黄囊水肿、心包囊水肿和身体弯曲的影响.根据急性毒性结果可知,毒性大小为S⁃CYF>Rac⁃CYF>R⁃CYF,其中S⁃CYF的毒性是R⁃CYF的2.3倍.72 hpf,500 mg·L^(-1)的S⁃CYF可显著诱导胚胎产生卵黄囊水肿(YSE)、体轴弯曲(CB)等畸形效应(pRac⁃CYF>R⁃CYF,表明丁氟螨酯对斑马鱼胚胎存在显著的对映选择性发育毒性,研究结果为丁氟螨酯的环境风险评估提供了理论依据.

关键词：丁氟螨酯斑马鱼急性毒性发育毒性对映选择性毒性

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Understanding the catalysis of chromium trioxide added magnesium hydride for hydrogen storage and Li ion battery applications

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Journal of Magnesium and Alloys 2024年第3期12卷 1117-1130页

作者： d.Pukazhselvan IhsanÇaha Catarina de Lemos Sergey M.Mikhalev francis Leonard deepak duncan Paul Fagg department of Mechanical Engineering TEMA-Centre for Mechanical Technology and AutomationUniversity of AveiroAveiro 3810-193Portugal LASI-Intelligent Systems Associate Laboratory Guimarães 4800-058Portugal Nanostructured Materials Group International Iberian Nanotechnology Laboratory(INL)Avenida Mestre Jose VeigaBraga 4715-330Portugal

This study explores how the chemical interaction between magnesium hydride(MgH_(2))and the additive CrO_(3) influences the hydrogen/lithium storage characteristics of MgH_(2).We have observed that a 5 wt.%CrO_(3) additive reduces the dehydrogenation activation energy of MgH_(2) by 68 kJ/mol and lowers the required dehydrogenation temperature by 80℃.CrO_(3) added MgH_(2) was also tested as an anode in an Li ion battery,and it is possible to deliver over 90%of the total theoretical capacity(2038 mAh/g).Evidence for improved reversibility in the battery reaction is found only after the incorporation of additives with MgH_(2).In depth characterization study by X-ray diffraction(XRd)technique provides convincing evidence that the CrO_(3) additive interacts with MgH_(2) and produces Cr/MgO *** free energy analyses confirm the thermodynamic feasibility of conversion from MgH_(2)/CrO_(3) to MgO/Cr,which is well supported by the identification of Cr(0)in the powder by X ray photoelectron spectroscopy(XPS)*** high resolution transmission electron microscopy(HRTEM)and energy dispersive spectroscopy(EdS)we found evidence for the presence of 5 nm size Cr nanocrystals on the surface of MgO rock salt *** is also convincing ground to consider that MgO rock salt accommodates Cr in the *** observations support the argument that creation of active metal–metal dissolved rock salt oxide interface may be vital for improving the reactivity of MgH_(2),both for the improved storage of hydrogen and lithium.

关键词： Hydrogen storage Rechargeable batteries Binary hydrides Metal oxides Catalytic mechanism.

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SEIRS model for malaria transmission dynamics incorporating seasonality and awareness campaign

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Infectious disease Modelling 2024年第1期9卷 84-102页

作者： francis Oketch Ochieng department of Pure and Applied Mathematics Jomo Kenyatta University of Agriculture and TechnologyNairobi62000-00200Kenya

Malaria,a devastating disease caused by the Plasmodium parasite and transmitted through the bites of female Anopheles mosquitoes,remains a significant public health concern,claiming over 600,000 lives annually,predominantly among *** tools,including the application of Wolbachia,are being developed to combat malaria-transmitting *** study presents a modified susceptible-exposed-infectious-recovered-susceptible(SEIRS)compartmental mathematical model to evaluate the impact of awareness-based control measures on malaria transmission dynamics,incorporating mosquito interactions and *** the next-generation matrix approach,we calculated a basic reproduction number(R0)of 2.4537,indicating that without robust control measures,the disease will persist in the human *** model equations were solved numerically using fourth and fifth-order Runge-Kutta *** model was fitted to malaria incidence data from Kenya spanning 2000 to 2021 using least squares curve *** fitting algorithm yielded a mean absolute error(MAE)of 2.6463 when comparing the actual data points to the simulated values of infectious human population(Ih).This finding indicates that the proposed mathematical model closely aligns with the recorded malaria incidence *** optimal values of the model parameters were estimated from the fitting algorithm,and future malaria dynamics were projected for the next *** research findings suggest that social media-based awareness campaigns,coupled with specific optimization control measures and effective management methods,offer the most cost-effective approach to managing malaria.

关键词： SEIRS model Malaria transmission dynamics Model fitting Basic reproduction number Stability analysis Seasonality Awareness campaign Runge–Kutta method

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Synthesis of nanostructured zinc oxide and its composite with carbon dots for dSSCs applications using flexible electrode

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Materials Reports(Energy) 2024年第3期4卷 77-83页

作者： Habtamu Fekadu Etefa francis Birhanu dejene department of Physics Walter Sisulu UniversityPrivate Bag X-1Mthatha5117South Africa

ZnO nanowires(ZnO NWs),ZnO nanoparticles(ZnO NPs)and carbon dots(C-dots)were synthesized by hydrothermal,sol-gel and hydrothermal methods *** were also characterized and applied for dye sensitized solar cells(dSSCs).The effects of C-dots on ZnO NWs and ZnO NPs have been *** C-dots were used at a mole ratio of citric acid(CA)to ethylene diamine(EdA)of 1:*** C-dots were found to enhance the performance of the flexible electrode *** the addition of C-dots,the power conversion efficiency(PCE)of ZnO NPs was boosted to be two times higher than that of ZnO NPs dSSCs without ***,the ultraviolet(UV)-band revealed a blue shift,resulting in a lower band gap and a reduced charge transfer resistance,which can enhance the PCE of *** loaded quantity on the flexible electrode substrate made of polyethylene terephthalate(PET)was optimized(50 mg).For dSSCs,the PET flexible electrode conductive polymer has produced positive *** ZnO NWs and ZnO NWs@C-dots,the PCE values were 1.45%and 4.25%;while for ZnO NPs and ZnO NPs@C-dots,they were 2.34%and 5.81%,*** work achieved remarkable and competitive performance when compared to solid(indium tin oxides/glass)-based substrate.

关键词： ZnO NWs@C-dots ZnO NPs@C-dots PET dSSCs Flexible electrode

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Fuzzy difference Equations in diagnoses of Glaucoma from Retinal Images Using deep Learning

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Computer Modeling in Engineering & Sciences 2024年第4期139卷 801-816页

作者： d.dorathy Prema Kavitha L.francis Raj Sandeep Kautish Abdulaziz S.Almazyad Karam M.Sallam Ali Wagdy Mohamed department of Mathematics Voorhees CollegeVelloreTamil NaduIndia Chandigarh Group of Colleges JhanjeriMohaliPunjabIndia department of Computer Engineering College of Computer and Information SciencesKing Saud UniversityP.O.Box 51178Riyadh11543Saudi Arabia Faculty of Science and Technology School of IT and SystemsUniversity of CanberraCanberraAustralia Operations Research department Faculty of Graduate Studies for Statistical ResearchCairo UniversityGiza12613Egypt Applied Science Research Center Applied Science Private UniversityAmman11937Jordan

The intuitive fuzzy set has found important application in decision-making and machine *** enrich and utilize the intuitive fuzzy set,this study designed and developed a deep neural network-based glaucoma eye detection using fuzzy difference equations in the domain where the retinal images *** image detections are categorized as normal eye recognition,suspected glaucomatous eye recognition,and glaucomatous eye *** degrees associated with weighted values are calculated to determine the level of concentration between the fuzzy partition and the retinal *** proposed model was used to diagnose glaucoma using retinal images and involved utilizing the Convolutional Neural Network(CNN)and deep learning to identify the fuzzy weighted regularization between *** methodology was used to clarify the input images and make them adequate for the process of glaucoma *** objective of this study was to propose a novel approach to the early diagnosis of glaucoma using the Fuzzy Expert System(FES)and Fuzzy differential equation(FdE).The intensities of the different regions in the images and their respective peak levels were *** the peak regions were identified,the recurrence relationships among those peaks were then *** partitioning was done due to varying degrees of similar and dissimilar concentrations in the *** and dissimilar concentration levels and spatial frequency generated a threshold image from the combined fuzzy matrix and *** distinguished between a normal and abnormal eye condition,thus detecting patients with glaucomatous eyes.

关键词： Convolutional Neural Network(CNN) glaucomatous eyes fuzzy difference equation intuitive fuzzy sets image segmentation retinal images

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The Potential Game-Changer:A Concept-to-Proof Study on d:A Heterojunction-free Organic Photovoltaics

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Chinese Journal of Chemistry 2024年第3期42卷 252-258页

作者： Lijian Zuo Sae Byeok Jo Xueliang Shi francis Lin Alex Jen State Key Laboratory of Silicon and Advanced Semiconductor Materials MOE Key Laboratory of Macromolecular Synthesis and FunctionalizationDepartment of Polymer Science and EngineeringZhejiang UniversityHangzhouZhejiang310058 China department of Materials Science and Engineering University of WashingtonSeattleWAUSA School of Chemical Engineering Sungkyunkwan University (SKKU)Suwon16419 Republic of Korea School of Chemistry and Molecular Engineering East China Normal UniversityShanghai200062 China department of Materials Science and Engineering City University of Hong KongKowloonHong KongChina department of Chemistry City University of Hong KongKowloonHong KongChina Hong Kong Institute for Clean Energy Hong KongChina

Since 1986,the donor-acceptor (d:A) heterojunction has been regarded a necessity for high-efficiency organic photovoltaics (OPVs),due to its unique advantage in compensating the intrinsic limitations of organic semiconductors,such as high exciton binding energy and poor ambipolar charge mobility. While this adversely causes tremendous non-radiative charge recombination and instability issues,which currently become the most critical limits for commercialization of OPVs. Here,we present a concept-to-proof study on the potential of d:A heterojunction free OPV by taking advantage of recent progress of non-fullerene acceptors. First,we demonstrate that the “free carriers” can be spontaneously generated upon illumination in an NFA,i.e.,the 6TIC-4F single layer. Second,the 6TIC-4F layer also exhibits good ambipolar charge transporting property. These exceptional characteristics distinguish it from the traditional organic semiconductors,and relieve it from the reliance of d:A heterojunction to independently work as active layer. As a result,the subsequent OPV by simply sandwiching the 6TIC-4F layer between the cathode and anode yields a considerably high power conversion efficiency ~1%. Moreover,we find the d:A heterojunction free device exhibits two order of magnitude higher electroluminescence quantum efficiency and significantly reduced VOC loss by 0.16 eV compared to those of the d:A BHJ structure,validating its promise for higher efficiency in the future. Therefore,our work demonstrates the possibility of using d:A heterojunction-free device structure for high performance,that can potentially become the next game changer of OPV.

关键词： Organic solar cells Spontaneous charge generation Ambipolar charge transport Charge recombination Perovskite-like organic semiconductor Schottky-junction structure Single component

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doped low-density parity-check codes

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digital Communications and Networks 2024年第1期10卷 217-226页

作者： Yong Li Rui Liu Xianlong Jiao Youqiang Hu Zhen Luo francis C.M.Lau College of Computer Science Chongqing UniversityChongqing400044China School of Automation Chongqing UniversityChongqing400044China College of Electronic and Information Engineering Southwest UniversityChongqing400715China Future Wireless Networks and IoT Focusing Area Department of Electronic and Information EngineeringHong Kong Polytechnic UniversityHong KongChina

In this paper,we propose a doping approach to lower the error floor of Low-density Parity-Check(LdPC)*** doping component is a short block code in which the information bits are selected from the coded bits of the dominant trapping sets of the LdPC ***,an algorithm for selecting the information bits of the short code is proposed,and a specific two-stage decoding algorithm is *** results demonstrate that the proposed doped LdPC code achieves up to 2.0 dB gain compared with the original LdPC code at a frame error rate of 10^(-6)Furthermore,the proposed design can lower the error floor of original LdPC Codes.

关键词： LdPC codes doped LdPC codes Tanner graph Quadratic residue codes Trapping sets

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