检索结果-南通市图书馆

Complicated expansion trajectories of insertion sequences and potential association with horizontal transfer of Wolbachia DNA

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Zoological Research 2023年第2期44卷 273-275页

作者： Yun-Heng Miao da-wei huang Jin-Hua Xiao College of Life Sciences Nankai UniversityTianjin 300071China

DEAR EDITOR,Insertion sequences(ISs) are the simplest structural transposable elements(TEs) in prokaryotes, consisting only of a transposase coding sequence and its bilateral short terminal inverted repeats. Due to their gradually streamlined genomic construction, TEs rarely exist in the genomes of obligate endosymbionts. However, TE content, especially ISs.

关键词： sequences insertion Wolbachia

Effect of laser shock peening on combined low- and high-cycle fatigue life of casting and forging turbine blades

在线全文

学校读者我要写书评

暂无评论

Journal of Iron and Steel Research International 2018年第1期25卷 108-119页

作者： Cao Chen Xiao-yong Zhang Xiao-jun Yan Jun Ren da-wei huang Ming-jing Qi School of Energy and Power Engineering BeihangUniversity Beijing 100191 China Collaborative Innovation Center of Advanced Aero-Engine Beijing 100191 China National Key Laboratory of Science and Technologyon Aero-Engine Aero-Thermodynamics Beijing 100191China Beijing Key Laboratory of Aero-Engine Structureand Strength Beijing 100191 China

Laser shock peening （LSP） is a novel effective surface treatment method to improve the fatigue performance of turbine blades. To study the effect of LSP on combined low- and high-cycle fatigue （CCF） life of turbine blades, the CCF tests were conducted at elevated temperatures on two types of full-scale turbine blades, which were made of K403 by casting and GH4133B by forging. Probabilistic analysis was conducted to find out the effect of LSP on fatigue life of those two kinds of blades. The results indicated that LSP extended the CCF life of both casting blades and forging blades obviously, and the effect of LSP on casting blades was more evident; besides, a threshold vibration stress existed for both casting blades and forging blades, and the CCF life tended to be extended by LSP only when the vibration stress was below the threshold vibra- tion stress. Further study of fractography was also conducted, indicating that due to the presence of compressive residual stress and refined grains induced by LSP, the crack initiation sources in LSP blades were obviously less, and the life of LSP blades was also longer; since the compressive residual stress was released by plastic deformation, LSP had no effect or adverse effect on CCF life of blade when the vibration stress of blade was above the threshold vibration stress.

关键词： Laser shock peening Combined low-and high-cycle fatigue life (CCF) Full-scale turbine blade S-N curve -Threshold vibration stress

Pollinating fig wasp Ceratosolen solmsi adjusts the offspring sex ratio to other foundresses

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Insect Science 2013年第2期20卷 228-234页

作者： Hao-Yuan Hu Zhong-Zheng Chen Zi-Feng Jiang da-wei huang Li-Ming Niu Yue-Guan Fu Key Laboratory of Biotic Environment and Ecological Safety in Anhui Province College of Life Sciences Anhui Normal University Wuhu Anhui Province China Department of Biology University of Maryland College Park Maryland USA Key Laboratory of Zoological Systematics and Evolution Institute of Zoology Chinese Academy of Sciences Beijing China Plant Protection College Shandong Agricultural University Tai'an Shandong Province China Environment and Plant Protection Institute Chinese Academy of Tropical Agricultural Sciences Danzhou Hainan Province China

Local mate competition theory predicts that offspring sex ratio in pollinating fig wasps is female-biased when there is only one foundress, and increased foundress density results in increased offspring sex ratio. Information of other foundresses and clutch size have been suggested to be the main proximate explanations for sex ratio adjustment under local mate competition. Our focus was to show the mechanism of sex ratio adjustment in a pollinating fig wasp, Ceratosolen solmsi Mayr, an obligate pollinator of the functionally dioecious fig, Ficus hispida Linn., with controlled experiments in the field. First, we obtained offspring from one pollinator and offspring at different oviposition sequences, and found that offspring sex ratio decreased with clutch size, and pollinators produced most of their male offspring at the start of bouts, followed by mostly females. Second, we found that offspring sex ratio increased with foundress density, and pollinators did adjust their offspring sex ratio to other females in the oviposition patches. We suggest that when oviposition sites are not limited, pollinators will mainly adjust their offspring sex ratio to other foundresses independent of clutch size changes, whereas adjusting clutch size may be used to adjust sex ratio when oviposition sites are limited.

关键词： behavior co-evolution local mate competition mutualism pollinating figwasp sex ratio adjustment

High incidences and similar patterns of Wolbachia infection in fig wasp communities from three different continents

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Insect Science 2010年第2期17卷 101-111页

作者： Lin-Lin Chen James M. Cook Hui Xiao Hao-Yuan Hu Li-Ming Niu da-wei huang Key Laboratory of Zoological Systematics and Evolution Institute of Zoology Chinese Academy of Sciences Beijing China Graduate University of Chinese Academy of Sciences Beijing China School of Biological Sciences University of Reading Reading UK College of Plant Protection Shandong Agricultural University Tai'an Shandong Province China

Wolbachia are endosymbiotic bacteria that infect numerous arthropod species. Previous studies in Panama and Australia revealed that the majority of fig wasp species harbor Wolbachia infections, but that similar patterns of incidence have evolved inde- pendently with different wasp species and Wolbachia strains on the two continents. We found Wolbachia infections in 25/47 species （53%） of fig wasp associated with 25 species of Chinese figs. Phylogenetic analyses of Wotbachia wsp sequences indicated that very similar strains are not obviously found in either closely related or ecologically linked fig wasps species. The extremely high prevalence of Wolbachia in fig wasps （over 50% of species infected） is not constrained by geographical origin and is a recurrent theme of fig wasp/Wolbachia interactions.

关键词： fig wasps horizontal transmission Wolbachia wsp

Isolation of microsatellite loci in the pollinating fig wasp of Ficus hispida, Ceratosolen solmsi

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Insect Science 2008年第4期15卷 303-306页

作者： Hao Yu Tong-Xin Zhang Hao-Yuan Hu Li-Ming Niu Hui Xiao Yan-Zhou Zhang da-wei huang Institute of Zoology Chinese Academy of Sciences Beijing Graduate School of the Chinese Academy of Sciences Beijing Plant Protection College Shandong Agricultural University Tai' an Shandong China

Microsatellite loci were isolated for Ceratosolen solmsi, pollinator of the dioecious Ficus hispida. We developed nine polymorphic microsatellite loci based on the method of polymerase chain reaction isolation of microsatellite arrays （PIMA）. Enrichment of genomic libraries was performed by random amplified polymorphic DNA （RAPD）. A subset of 38 positive clones was sequenced; 15 clones showed microsatellite loci. We tested 15 designed primer pairs and nine of them produced polymorphic amplification in 48 individual wasps collected from different fruits of the dioecious host fig Ficus hispida in China. Among the 48 individuals, 49 alleles were obtained at the nine loci. The observed heterozygosity ranged between 0.357 and 0.634.

关键词： Ficus fig wasp markers microsatellite loci polymorphism primers

Evolutionary timescale of chalcidoid wasps inferred from over one hundred mitochondrial genomes

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Zoological Research 2023年第3期44卷 467-482页

作者： Jia-Chen Zhu Hui Xiao Pu Tang Xiao-Fei Li Xuan-Kun Li Chao-Dong Zhu Qiong Wu Jin-Hua Xiao Cornelis van Achterberg da-wei huang Xue-Xin Chen State Key Laboratory of Rice Biology Ministry of Agriculture and Rural Affairs Key Lab of Molecular Biology of Crop Pathogens and Insect PestsProvincial Key Lab of Biology of Crop Pathogens and Insect Pests of ZhejiangInstitute of Insect SciencesZhejiang UniversityHangzhouZhejiang 310058China Key Laboratory of Zoological Systematics and Evolution Institute of ZoologyChinese Academy of SciencesBeijing 100101China Florida Museum of Natural History University of FloridaGainesvilleFL 32611 USA College of Life Sciences Nankai UniversityTianjin 300071China

Chalcidoidea is one of the most biologically diverse groups among *** are characterized by extraordinary parasitic lifestyles and extensive host ranges,among which several species attack plants or serve as ***,higher-level chalcidoid relationships remain ***,we performed mitochondrial phylogenomic analyses for major clades(18out of 25 families)of Chalcidoidea based on 139 mitochondrial *** compositional heterogeneity and conflicting backbone relationships in Chalcidoidea were assessed using various datasets and tree *** phylogenetic results supported the monophyly of 16families and polyphyly of Aphelinidae and *** preferred topology recovered the relationship(Mymaridae+(Signiphoridae+Leucospidae)+(Chalcididae+((Perilampidae+Eucharitidae)+remaining Chalcidoidea))).The monophyly of Agaonidae and Sycophaginae was rejected,while the gall-associated((Megastigmidae+Ormyridae)+(Ormocerinae+Eurytomidae))relationship was supported in most results.A six-gene inversion may be a synapomorphy for most families,whereas other derived gene orders may introduce confusion in phylogenetic signals at deeper *** estimates suggested that Chalcidoidea arose near the Jurassic/Cretaceous boundary and that two dynamic shifts in diversification occurred during the evolution of *** hypothesized that the potential codiversification between chalcidoids and their hosts may be crucial for accelerating the diversification of *** state reconstruction analyses supported the hypothesis that gallinducers were mainly derived from parasitoids of gallinducers,while other gall-inducers were derived from phytophagous *** together,these findings advance our understanding of mitochondrial genome evolution in the major interfamilial phylogeny of Chalcidoidea.

关键词： Mitochondrial genome Chalcidoidea Compositional heterogeneity Divergence time Evolution of host and gall associations

Weak Anti-Localization and Quantum Oscillations in Topological Crystalline Insulator PbTe

在线全文

学校读者我要写书评

暂无评论

Chinese Physics Letters 2017年第2期34卷 67-70页

作者： Ke-Jie Wang wei Wang Min-Hao Zhang Xiao-Qian Zhang Pei Yang Bo Liu Ming Gao da-wei huang Jun-Ran Zhang Yu-Jie Liu Xue-Feng Wang Feng-Qiu Wang Liang He Yong-Bing Xu Rong Zhang Jiangsu Provincial Key Laboratory of Advanced Photonic and Electronic Materials Jiangsu Provincial Key Laboratory for NanotechnologyCollaborative Innovation Center of Advanced MicrostructuresSchool of Electronic Science and EngineeringNanjing UniversityNanjing 210093

Topological crystalline insulators （TCIs） have attracted worldwide interest since their theoretical predication and have created exciting opportunities for studying topological quantum physics and for exploring spintronic appli- cations. In this work, we successfully synthesize PbTe nanowires via the chemical vapor deposition method and demonstrate the existence of topological surface states by their 2D weak anti-localization effect and Shubnikov-de Haas oscillations. More importantly, the surface state contributes ~61% of the total conduction, suggesting dom- inant surface transport in PbTe nanowires at low temperatures. Our work provides an experimental groundwork for researching TCIs and is a step forward for the applications of PbTe nanowires in spintronic devices.

关键词： Weak Anti-Localization and Quantum Oscillations in Topological Crystalline Insulator PbTe length

Unraveling the Stray Current-Induced Interfacial Transition Zone(ITZ)Effect on Sulfate Corrosion in Concrete

在线全文

学校读者我要写书评

暂无评论

Engineering 2024年第10期41卷 130-152页

作者： Yong-Qing Chen Lin-Ya Liu da-wei huang Qing-Song Feng Ren-Peng Chen Xin Kang School of Transportation Engineering East China Jiaotong UniversityNanchang 330013China College of Civil Engineering Hunan UniversityChangsha 410082China Key Laboratory of Building Safety and Energy Efficiency of Ministry of Education&National Center for International Research Collaboration in Building Safety and Environment Hunan UniversityChangsha 410082China

The rail transit in sulfate-rich areas faces the combined effects of stray current and salt corrosion;however,the sulfate ion transport and concrete degradation mechanisms under such conditions are still *** address this issue,novel sulfate transport and mesoscale splitting tests were designed,with a focus on considering the differences between the interfacial transition zone(ITZ)and cement *** the influence of stray current,the ITZ played a pivotal role in regulating the transport and mechanical failure processes of sulfate attack,while the tortuous and blocking effects of aggregates almost *** phenomenon was termed the“stray current-induced ITZ effect.”The experimental data revealed that the difference in sulfate ion transport attributed to the ITZ ranged from 1.90 to 2.31 times,while the difference in splitting strength ranged from 1.56 to 1.64 *** the real-time synchronization of splitting experiments and microsecond-responsive particle image velocimetry(PIV)technology,the mechanical properties were exposed to the consequences of the stray currentinduced ITZ *** number of splitting cracks in the concrete increased,rather than along the central axis,which was significantly different from the conditions without stray current and the ideal Brazilian disk ***,a sulfate ion mass transfer model that incorporates reactivity and electrodiffusion was meticulously *** embedded finite element calculation exhibited excellent agreement with the experimental results,indicating its reliability and ***,the stress field was determined utilizing analytical methods,and the mechanism underlying crack propagation was successfully *** to the cement matrix,a stray current led to more sulfates,more microstructure degradation,and greater increases in thickness and porosity in the ITZ,which was considered to be the essence of the stray current-induced ITZ effect.

关键词： Interfacial transition zone(ITZ)effect Stray current Sulfate attack Transport mechanism Splitting test Microstructure

Modeling dam deformation using independent component regression method

在线全文

学校读者我要写书评

暂无评论

Transactions of Nonferrous Metals Society of China 2013年第7期23卷 2194-2200页

作者：戴吾蛟刘斌丁晓利黄大伟中南大学地球科学与信息物理学院长沙410083 香港理工大学土地测量与地理咨讯系香港九龙红磡999077

In the application of regression analysis method to model dam deformation, the ill-condition problem occurred in coefficient matrix always prevents an accurate modeling mainly due to the multicollinearity of the variables. Independent component regression （ICR） was proposed to model the dam deformation and identify the physical origins of the deformation. Simulation experiment shows that ICR can successfully resolve the problem of ill-condition and produce a reliable deformation model. After that, the method is applied to model the deformation of the Wuqiangxi dam in Hunan province, China. The result shows that ICR can not only accurately model the deformation of the dam, but also help to identify the physical factors that affect the deformation through the extracted independent components.

关键词： dam deformation analysis independent component regression principal component regression ill-condition problem interpreting of dam deformation