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基于PCA-XGBoost算法的哑铃状SIR差分滤波器设计

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磁性材料及器件 2024年第1期55卷 31-36页

作者：张友俊徐雯雯上海海事大学信息工程学院上海201306

随着多业务无线通信技术的发展,具有共模抑制能力的差分带通滤波器越来越受到人们的关注,但是设计差分微带滤波器的传统方法过程复杂且耗时较长。针对这些问题,结合非线性赋权的极限梯度提升(eXtreme Gradient Boosting,XGBoost)算法,... 详细信息

随着多业务无线通信技术的发展,具有共模抑制能力的差分带通滤波器越来越受到人们的关注,但是设计差分微带滤波器的传统方法过程复杂且耗时较长。针对这些问题,结合非线性赋权的极限梯度提升(eXtreme Gradient Boosting,XGBoost)算法,通过训练和学习滤波器结构参数和相应频率响应S参数的关系辅助进行滤波器的设计,设计了一款基于改进阶跃阻抗谐振器(Stepped Impedance Resonator,SIR)的哑铃状差分带通滤波器。该滤波器的中心频率为2.6 GHz,相对带宽为7.3%,通带内插入损耗优于0.95 dB,回波损耗优于20 dB,通带内共模抑制优于42 dB,并且具有较宽的阻带。实物测试结果与算法预测结果的一致性,验证了PCA-XGBoost算法(Principal Component Analysis,PCA)用于滤波器辅助设计的可行性。

关键词：哑铃状SIR谐振器差分微带滤波器 PCA-XGBoost算法

Lack of fitness cost and inheritance of resistance to abamectin based on the establishment of a near-isogenic strain of Tetranychus urticae

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Journal of Integrative Agriculture 2023年第6期22卷 1809-1819页

作者： zhang Yan TIAN Tian zhang Kun zhang you-jun WU Qing-jun XIE Wen GUO Zhao-jiang WANG Shao-li State Key Laboratory of Vegetable Biobreeding Institute of Vegetables and FlowersChinese Academy of Agricultural SciencesBeijing 100081P.R.China College of Agriculture Yangtze UniversityJingzhou 434025P.R.China Sanya Nanfan Research Institute Hainan UniversitySanya 572024P.R.China

Many populations of the two-spotted spider mite, Tetranychus urticae Koch, have developed high levels of resistance to the pesticide abamectin in China and other countries. This study developed a near-isogenic line to understand better the inheritance, cross-resistance, and fitness costs associated with abamectin resistance in the field population of T. urticae in China. We introduced the trait that confers extremely high abamectin resistance in a field-collected population of T. urticae into a susceptible laboratory strain(IPP-SS) to generate an abamectin-resistant near-isogenic line(NIL-Aba).This process was carried out through multiple backcrossing to IPP-SS and via parthenogenesis and abamectin screening. Compared with IPP-SS, the NIL-Aba strain had a 25 147-fold resistance to abamectin and a high level of cross-resistance to bifenthrin(288.17-fold), an intermediate level to emamectin benzoate(42.57-fold), and low levels to bifenazate, chlorfenapyr, cyflumetofen, cyenopyrafen, and cyetpyrafen with resistance ranging from 3.18-to *** it had no cross-resistance to profenofos. The resistance to abamectin in NIL-Aba was autosomal, incompletely dominant, and polygenic. Based on two sex life table parameters, no fitness cost was found in NIL-Aba. Establishing the NIL-Aba strain provides a reliable basis for an in-depth study of abamectin resistance in T. urticae. New information on toxicological characteristics and fitness cost should facilitate the management of abamectin resistance in field populations of T. urticae.

关键词： two-spotted spider mite abamectin resistance near-isogenic strain inheritance pattern fitness cost

Characterization of the chemosensory protein EforCSP3 and its potential involvement in host location by Encarsia formosa

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Journal of Integrative Agriculture 2023年第2期22卷 514-525页

作者： WANG Ke HE Yan-yan zhang you-jun GUO Zhao-jiang XIE Wen WU Qing-jun WANG Shao-li Institute of Vegetables and Flowers Chinese Academy of Agricultural SciencesBeijing 100081P.R.China

Chemosensory proteins(CSPs) perform several functions in *** study performed the gene expression,ligand-binding,and molecular docking assays on the EforCSP3 identified in the parasitoid wasp Encarsia formosa,to determine whether EforCSP3 functions in olfaction,especially in host location and host *** results showed that EforCSP3 was highly expressed in the female head,and its relative expression was much higher in adults than in other developmental *** fluorescence binding assays suggested that the EforCSP3 exhibited high binding affinities to a wide range of host-related volatiles,among which dibutyl phthalate,1-octene,β-elemene,and tridecane had the strongest binding affinity with EforCSP3,besides α-humulene and β-myrcene,and should be assessed as potential *** structure modeling and molecular docking predicted the amino acid residues of EforCSP3possibly involved in volatile binding.α-Humulene and β-myrcene attracted *** in a previous study and exhibited strong binding affinities with EforCSP3 in the current *** conclusion,EforCSP3 may be involved in semiochemical reception by ***.

关键词： Encarsia formosa chemosensory protein expression profiles fluorescence binding assay molecular docking

Comparative Analysis of Population Genetic Structure in Bemisia tabaci(Gennadius) Biotypes B and Q Based on ISSR Marker

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Agricultural Sciences in China 2008年第11期7卷 1348-1354页

作者： CHU Dong WAN Fang-hao XU Bao-yun WU Qing-jun zhang you-jun High-Tech Research Center Shandong Academy of Agricultural Sciences Jinan 250100 P.R.China Institute of Vegetables and Flowers Chinese Academy of Agricultural Sciences Beijing 100081 P.R. China The State Key Laboratory for Biology of Plant Diseases and Insect Pests Institute of Plant Protection Chinese Academy of Agricultural Scienees Beijing 100081 P.R. China

Bemisia tabaci （Gennadius） biotypes B and Q are two invasive biotypes in the species complex. The comparison of the population genetic structure of the two biotypes is of significance to show their invasive mechanism and to their control. The intersimple sequence repeats （ISSR） marker was used to analyze the 16 B-biotype populations and 4 Q-biotype populations worldwide with a Trialeurodes vaporariorum population in Shanxi Province, China, and a B. tabaci non-B/Qbiotype population in Zhejiang Province, China, was used as control populations. The analysis of genetic diversity showed that the diversity indexes of biotype Q including Nei＇s gene diversity index, Shannon informative index, and the percentage of polymorphic loci were higher than those of biotype B. The high genetic diversity of biotype Q might provide the genetic basis for the excellent ecological adaptation. Cluster analysis suggested that the ISSR could not be used in the phylogenetic analysis though it could easily distinguish the biotypes of B. tabaci. The difference of the population genetic structure between the biotype B and the biotype Q exists based on the ISSR marker. Meanwhile, the results suggested that the molecular marker has its limitation in the phylogenetic analysis among the biotypes of B. tabaci.

关键词： invasive mechanism Bemisia tabaci biotype B Bemisia tabaci biotype Q genetic structure ISSR

CRISPR/Cas9-based functional characterization of Px ABCB1 reveals its roles in the resistance of Plutella xylostella(L.)to Cry1Ac,abamectin and emamectin benzoate

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农业科学学报:英文版 2023年第10期22卷 3090-3102页

作者： OUYANG Chun-zheng YE Fan WU Qing-jun WANG Shao-li Neil CRICKMORE ZHOU Xu-guo GUO Zhao-jiang zhang you-jun State Key Laboratory of Vegetable Biobreeding Deapartment of Plant ProtectionInstitute of Vegetables and FlowersChinese Academy of Agricultural SciencesBeijing 100081P.R.China Guangdong Laboratory for Lingnan Modern Agriculture Guangzhou 510642P.R.China School of Life Sciences University of SussexBrighton BN19QGUK Department of Entomology University of KentuckyLexingtonKY 40546-0091USA

The identification of functional midgut receptors for pesticidal proteins produced by Bacillus thuringiensis(Bt)is critical for deciphering the molecular mechanism of Bt resistance in *** expression of the PxABCB1 gene was previously found to be associated with Cry1Ac resistance in the diamondback moth,Plutella xylostella(L.).To directly validate the potential receptor role of PxABCB1 and its contribution to Bt Cry1Ac toxicity in ***,we used CRISPR/Cas9 to generate a homozygous knockout ABCB1KO strain with a 5-bp deletion in exon 3 of its *** ABCB1KO strain exhibited a 63-fold resistance to Cry1Ac toxin compared to the parental DBM1Ac-S ***,the ABCB1KO strain also exhibited significant increases in susceptibility to abamectin and emamectin *** changes in susceptibility to various other Bt Cry proteins or synthetic insecticides were *** knockout strain exhibited no significant fitness ***,our study indicates that PxABCB1 can protect the insect against avermectin insecticides on one hand,while on the other hand it facilitates the toxic effect of the Bt Cry1Ac *** results of this study will help to inform integrated pest management approaches against this destructive pest.

关键词： Bacillus thuringiensis Plutella xylostella CRISPR/Cas9 ABCB1 bioinsecticide resistance

Sustainable, thermoplastic and hydrophobic coating from natural cellulose and cinnamon to fabricate eco-friendly catering packaging

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Green Energy & Environment 2024年第5期9卷 927-936页

作者： Rumeng Xu Chunchun Yin Jingxuan you Jinming zhang Qinyong Mi Jin Wu jun zhang CAS Key Laboratory of Engineering Plastics Institute of ChemistryChinese Academy of Sciences(CAS)Beijing100190China University of Chinese Academy of Sciences Beijing100049China

Non-degradable polymers cause serious environmental pollution problem,such as the widely-used while unrecyclable coatings which signiﬁcantly affect the overall degradation performance of *** is imperative and attractive to develop biodegradable functional ***,we proposed a novel strategy to successfully prepare biodegradable,thermoplastic and hydrophobic coatings with high transparence and biosafety by weakening the interchain interactions between cellulose *** natural cellulose and cinnamic acid were as raw *** reducing the degree of polymerization(DP)of cellulose and regulating the degree of substitution(DS)of cinnamate moiety,the obtained cellulose cinnamate(CC)exhibited not only the thermalﬂow behavior but also good biodegradability,which solves the conﬂict between the thermoplasticity and biodegradability in cellulose-based *** glass transition temperature(T_(g))and thermalﬂow temperature(T_(f))of the CC could be adjusted in a range of 150–200℃ and 180–210℃,*** CC with DS<1.2 and DP≤100 degraded more than 60%after an enzyme treatment for 7 days,and degraded more than 80%after a composting treatment for 42 ***,CC had no toxicity to human epidermal cells even at a high concentration(0.5 mg mL^(-1)).In addition,CC could be easily fabricated into multifunctional coating with high hydrophobicity,thermal adhesion and high ***,after combining with cellophane and paperboard,CC coating with low DP and DS could be used to prepare fully-biodegradable heat-sealing packaging,art paper,paper cups,paper straws and food packaging boxes.

关键词： Thermoplastic coating Bio-degradable adhesive Natural products Cellulose Eco-friendly packaging

Understanding adversarial attacks on observations in deep reinforcement learning

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Science China(Information Sciences) 2024年第5期67卷 69-83页

作者： you QIAOBEN Chengyang YING Xinning ZHOU Hang SU jun ZHU Bo zhang Department of Computer Science and Technology Beijing National Research Center for Information Science and Technology Tsinghua-Bosch Joint Center for Machine Learning Institute for Artificial Intelligence Tsinghua University Peng Cheng Laboratory

Deep reinforcement learning models are vulnerable to adversarial attacks that can decrease the cumulative expected reward of a victim by manipulating its observations. Despite the efficiency of previous optimization-based methods for generating adversarial noise in supervised learning, such methods might not achieve the lowest cumulative reward since they do not generally explore the environmental ***, a framework is provided to better understand the existing methods by reformulating the problem of adversarial attacks on reinforcement learning in the function space. The reformulation approach adopted herein generates an optimal adversary in the function space of targeted attacks, repelling them via a generic two-stage framework. In the first stage, a deceptive policy is trained by hacking the environment and discovering a set of trajectories routing to the lowest reward or the worst-case performance. Next, the adversary misleads the victim to imitate the deceptive policy by perturbing the observations. Compared to existing approaches, it is theoretically shown that our adversary is strong under an appropriate noise level. Extensive experiments demonstrate the superiority of the proposed method in terms of efficiency and effectiveness, achieving state-of-the-art performance in both Atari and MuJoCo environments.

关键词： deep learning reinforcement learning adversarial robustness adversarial attack

Manipulating Crystal Growth and Secondary Phase PbI_(2)to Enable Efficient and Stable Perovskite Solar Cells with Natural Additives

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Nano-Micro Letters 2024年第9期16卷 432-448页

作者： Yirong Wang Yaohui Cheng Chunchun Yin Jinming zhang Jingxuan you Jizheng Wang Jinfeng Wang jun zhang Institute of Chemistry Chinese Academy of Sciences(CAS)Beijing 100190People’s Republic of China University of Chinese Academy of Sciences Beijing 100049People’s Republic of China Nanjing University Nanjing 210023People’s Republic of China Wuhan Textile University Wuhan 430200People’s Republic of China

In perovskite solar cells(PSCs),the inherent defects of perovskite film and the random distribution of excess lead iodide(PbI_(2))prevent the improvement of efficiency and ***,natural cellulose is used as the raw material to design a series of cellulose derivatives for perovskite crystallization *** cationic cellulose derivative C-Im-CN with cyano-imidazolium(Im-CN)cation and chloride anion prominently promotes the crystallization process,grain growth,and directional orientation of ***,excess PbI_(2)is transferred to the surface of perovskite grains or formed plate-like crystallites in local *** effects result in suppressing defect formation,decreasing grain boundaries,enhancing carrier extraction,inhibiting non-radiative recombination,and dramatically prolonging carrier ***,the PSCs exhibit a high power conversion efficiency of 24.71%.Moreover,C-Im-CN has multiple interaction sites and polymer skeleton,so the unencapsulated PSCs maintain above 91.3%of their initial efficiencies after 3000 h of continuous operation in a conventional air atmosphere and have good stability under high humidity *** utilization of biopolymers with excellent structure-designability to manage the perovskite opens a state-of-the-art avenue for manufacturing and improving PSCs.

关键词： Perovskite Solar cells Defect passivation Biomass additives Crystal orientation

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Genetic Differentiation of Different Geographical Populations of Bemisia tabaci (Gennadius) Complex

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Agricultural Sciences in China 2007年第6期6卷 696-705页

作者： CHU Dong LIU Guo-xia FAN Zhong-xue TAO Yun-li zhang you-jun High-Tech Research Center Shandong Academy of Agricultural Sciences Jinan 250100 P.R.China Institute of Vegetables and Flowers Chinese Academy of Agricultural Sciences Beijing 100081 P.R.China

Bemisia tabaci （Gennadius） is a species complex, which includes different geographical populations with genetic differentiation. The recent progress on the genetic differentiation of various geographical populations of B. tabaci complex was introduced. The genetic differentiation was further analyzed on the basis of the sequences of mtDNA COI and rDNA ITS1 recorded in the world＇s GenBank. Five groups are defined on the basis of mtDNA COI and rDNA ITS1, including the Asia group, America group, Africa group, Australia group, and Biotype B/Mediterranean/Middle East/ Northern Africa/Biotype Ms group. There are several ungrouped geographical classifications, such as the Uganda population, Ivory Coast population, and Taiwan population. Geographical isolation may be the most important factor that contributed to the genetic differentiation of various geographical populations of B. tabaci. Many populations with biological advantages invaded new regions and caused severe economic losses within human activity. It is necessary to strengthen the research of B. tabaci biotype to prevent the spread of invaded populations and the invasion of potentially dangerous populations.

关键词： Bemisia tabaci (Gennadius) geographical populations mtDNA COI rDNA ITS 1 genetic differentiation