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Evidence for a female-produced, long range pheromone of Anoplophora glabripennis （Coleoptera Cerambycidae）

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Insect Science 2012年第3期19卷 355-371页

作者： jacob d.Wickham Zhichun Xu Stephen A.Teale department of Environmental and Forest Biology SUNY College of Environmental Science and Forestry1 Forestry DriveSyracuseN Y 13210USA College of Forest Resources Beijing Forestry University Key Lab of Analytical Chemistry for Living Biosystems Institute of ChemistryChinese Academy of SciencesBeijingChina

Volatiles from female Asian longhorned beetle （ ALB ）, Anoplophora glabripenhis, were evaluated as candidate sex pheromone components. Previous studies on ALB have revealed several antennally active compounds from virgin females; however the origins and activity of these compounds were not apparent and require further investigation. We tested the hypothesis that one or more of the ALB contact sex pheromones is a precursor that undergoes abiotic oxidation to yield volatile pheromone components, and evaluated the activity of these compounds using laboratory and field bioassays. Gas chromatogra- phy coupled electroantennography detection （GC-EAd） analysis indicated the presence of three antennally active aldehydes （heptanal, nonanal, and hexadecanal） in female cuticular extracts exposed to ozone or UV and visible light. In laboratory bioassays using a Y-tube olfactometer, males were preferentially attracted to ozonized female body washes over crude body washes. Similarly, synthetic formulations of these compounds were preferred over controls in the olfactometer. Field trapping experiments conducted from 2006 to 2008 in Ningxia, China showed that synthetic lures of the three aldehydes formulated in a ratio simulating that of virgin females attracted more beetles compared to controls, and that combinations of these aldehydes, linalool oxide, and host kairomones captured more beetles than controls, and captured significantly more males.

关键词： Anoplophora glabripennis Asian longhorned beetle cuticular hydrocarbons,kairomone oxidation pheromone

A new bacteria-free strategy induced by MaGal2 facilitates pinewood nematode escape immune response from its vector beetle

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Insect Science 2021年第4期28卷 1087-1102页

作者： Chi Zhang jacob d.Wickham Lilin Zhao Jianghua Sun State Key Laboratory of Integrated Management of Pest Insects and Rodents Institute of ZoologyChinese Academy of SciencesBeijingChina CAS Center for Excellence in Biotic Interactions University of Chinese Academy of SciencesBeijingChina

Symbiotic microbes play a crucial role in regulating parasite–host interactions;however,the role of bacterial associates in parasite–host interactions requires *** this study,we showed that,instead of introducing numerous symbiotic bacteria,dispersal of 4th-stage juvenile(JIV)pinewood nematodes(PWNs),Bursaphelenchus xylophilus,only introduced few bacteria to its vector beetle,Monochamus alternatus(Ma).JIV showed weak binding ability to five dominant bacteria species isolated from the beetles’pupal *** was especially the case for binding to the opportunistic pathogenic species Serratia marcescens;the nematodes’bacteria binding ability at this critical stage when it infiltrates Ma for dispersal was much weaker compared with Caenorhabditis elegans,diplogasteroides asiaticus,and propagative-stage *** associated bacterium ***,which was isolated from the beetles’pupal chambers,was unfavorable to Ma,because it caused a higher mortality rate upon injection into *** addition,*** in the tracheae caused more immune effector disorders compared with PWN ***_Galectin2(MaGal2),a pattern-recognition receptor,was up-regulated following PWN *** MaGal2 protein formed aggregates with five dominant associated bacteria in ***,MaGal2 knockdown beetles had up-regulated prophenoloxidase gene expression,increased phenoloxidase activity,and decreased PWN *** study revealed a previously unknown strategy for immune evasion of this plant pathogen inside its vector,and provides novel insights into the role of bacteria in parasite–host interactions.

关键词： galectin immune evasion pinewood nematode symbiotic bacteria vector beetle

Fighting and aggressive sound determines larger male to win male-male competition in a bark beetle

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Insect Science 2021年第1期28卷 203-214页

作者： Zhu-dong Liu jacob d.Wickham Jiang-Hua Sun State Key Laboratory of Integrated Management of Pest Insects and Rodents Institute of ZoologyChinese Academy of SciencesChaoyang DistrictBeijingChina CAS Center for Excellence in Biotic Interactions Chinese Academy of SciencesChaoyang DistrictBeijingChina

Intrasexual selection occurs in male-male competition over access to females and usually results in the larger male *** much research has documented that size matters,little is known about how the larger male *** vale ns is an aggregating monogamous bark beetle in which males have large variation in body size and display intense competition over *** observation showed two males fight each other within the gallery by pushing/shoving and stridulated more when two males encountered each *** using two different-sized males synchronously competing showed that larger males won 95%of *** displacement experiments using muted and intact males of different or equal size were used to simulate male-male *** males displaced the smaller resident male in 90%of contests,while smaller males prevailed over larger residents in 6.7%of *** both males silenced,larger males displaced smaller males in 80%of con tests,while smaller males prevailed in 8%of con *** experiments using equal-sized males showed aggressive soundemitting males displaced muted males in 67%of contests,yet intact males displaced other intact males in only 37.5%of con *** analysis showed sound pressure level is an honest signal of body size and males chose soft sounds over loud aggressive sounds in ***,*** males have evolved dual behaviors,fighting and aggressive sounds associated with body size,to assess rivals to compete for a partner,gaining insights in male-male competition for this species and for other animals.

关键词： aggressive soun ds animal con test theory bark bee tie body size fighting male-male competition

Major ascaroside pheromone component asc-C5 influences reproductive plasticity among isolates of the invasive species pinewood nematode

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Integrative Zoology 2021年第6期16卷 893-907页

作者： Meiping ZHAO jacob d.WICKHAM Lilin ZHAO Jianghua SUN State Key Laboratory of Integrated Management of Pest Insects and Rodents Institute of ZoologyChinese Academy of SciencesBeijingChina CAS Center for Excellence in Biotic Interactions University of Chinese Academy of SciencesBeijingChina

Pheromones are communication chemicals and regulatory signals used by animals and represent unique tools for organisms to mediate behaviors and make“decisions”to maximize their *** plasticity refers to the innate capacity of a species to tolerate a greater breadth of environmental conditions across which it adapts to improve its survival,reproduction,and *** pinewood nematode,Bursaphelenchus xylophilus,an invasive nematode species,was accidentally introduced from North America into Japan,China,and Europe;however,few studies have investigated its pheromones and phenotypic plasticity as a natural ***,we demonstrated a novel phenomenon,in which nematodes under the condition of pheromone presence triggered increased reproduction in invasive strains(JP1,JP2,CN1,CN2,EU1,and EU2),while it simultaneously decreased reproduction in native strains(US1 and US2).The bidirectional effect on fecundity,mediated by presence/absence of pheromones,is henceforth termed pheromone-regulative reproductive plasticity(PRRP).We further found that synthetic ascaroside asc-C5(ascr#9),the major pheromone component,plays a leading role in PRRP and identified 2 candidate receptor genes,Bxydaf-38 and Bxysrd-10,involved in perceiving *** results suggest that plasticity of reproductive responses to pheromones in pinewood nematode may increase its fitness in novel environments following *** opens up a new perspective for invasion biology and presents a novel strategy of invasion,suggesting that pheromones,in addition to their traditional roles in chemical signaling,can influence the reproductive phenotype among native and invasive *** addition,this novel mechanism could broadly explain,through comparative studies of native and invasive populations of animals,a potential underlying factor behind of the success of other biological invasions.

关键词： Bursaphelenchus xylophilus fecundity invasion phenotypic plasticity pheromone

Progressive heterosis in genetically defined tetraploid maize

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Journal of Genetics and Genomics 2019年第8期46卷 389-396页

作者： jacob d.Washburn Mitchell J.McElfresh James A.Birchler division of Biological Sciences University of Missouri

Progressive heterosis, i.e., the additional hybrid vigor in double-cross tetraploid hybrids not found in their single-cross tetraploid parents, has been documented in a number of species including alfalfa,potato, and maize. In this study, four artificially induced maize tetraploids, directly derived from standard inbred lines, were crossed in pairs to create two single-cross hybrids. These hybrids were then crossed to create double-cross hybrids containing genetic material from all four original lines. Replicated fieldbased phenotyping of the materials over four years indicated a strong progressive heterosis phenotype in tetraploids but not in their diploid counterparts. In particular, the above ground dry weight phenotype of double-cross tetraploid hybrids was on average 34% and 56% heavier than that of the single-cross tetraploid hybrids and the double-cross diploid counterparts, respectively. Additionally,whole-genome resequencing of the original inbred lines and further analysis of these data did not show the expected spectrum of alleles to explain tetraploid progressive heterosis under the complementation of complete recessive model. These results underscore the reality of the progressive heterosis phenotype,its potential utility for increasing crop biomass production, and the need for exploring alternative hypothesis to explain it at a molecular level.

关键词： Maize Tetraploid Heterosis dominance complementation Progressive heterosis

distributed media cooperation for enhanced video communication

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2006年第5期7卷 773-783页

作者： CHAKARESKI jacob Ecole Polytechnique Fédérale de Lausanne

The author designed two algorithms for distributed cooperation among multiple video streams sharing common communication resources. The algorithms take advantage of an optimization framework that characterizes video packets such that joint resource allocation can be implemented not only over the packets of a single stream, but also across packets of different streams. The first algorithm enables collaboration among multiple video senders in an 802.11 CSMA/CA wireless network such that their joint performance is maximized. Via the algorithm, the users cooperatively establish transmission priorities based on the assigned characterizations of their video packets. The second technique allows for low-complexity joint bandwidth adaptation of multiple video streams at intermediate network nodes in the Internet in order to maximize the overall network performance. The author analyzes the advantages of the proposed algorithms over conventional solutions employed in such scenarios. It is shown that depending on system parameters such as available network data rate the proposed techniques can provide substantial gains in end-to-end performance.

关键词： Media cooperation, distributed video streaming, Wireless networks, Resource allocation, Rate-quality optimization

Comparing the Structural Parameters of the Milky Way to Other Spiral Galaxies

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Research in Astronomy and Astrophysics 2024年第3期24卷 10-28页

作者： jacob A.Guerrette Aleksandr V.Mosenkov dallin Spencer Zacory d.Shakespear department of Physics and AstronomyN283 ESCBrigham Young University ProvoUT 84602USA

The structural parameters of a galaxy can be used to gain insight into its formation and evolution *** this paper,we strive to compare the Milky Way’s structural parameters to other,primarily edge-on,spiral galaxies in order to determine how our Galaxy measures up to the Local *** our comparison,we use the galaxy structural parameters gathered from a variety of literature sources in the optical and near-infrared wave *** compare the scale length,scale height,and disk flatness for both the thin and thick disks,the thick-to-thin disk mass ratio,the bulge-to-total luminosity ratio,and the mean pitch angle of the Milky Way’s spiral arms to those in other *** conclude that many of the Milky Way’s structural parameters are largely ordinary and typical of spiral galaxies in the Local Universe,though the Galaxy’s thick disk appears to be appreciably thinner and less extended than expected from zoom-in cosmological simulations of Milky Way-mass galaxies with a significant contribution of galaxy mergers involving satellite galaxies.

关键词： Galaxy disk-galaxies fundamental parameters-Galaxy structure

Near-field enhancement of optical second harmonic generation in hybrid gold-lithium niobate nanostructures

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Light(Science & Applications) 2023年第5期12卷 855-866页

作者： Rana Faryad Ali jacob A.Busche Saeid Kamal david J.Masiello Byron d.Gates department of Chemistry and 4d LABS Simon Fraser UniversityBurnabyBCV5A 1S6Canada department of Chemistry University of WashingtonSeattleWA 98195USA

Nanophotonics research has focused recently on the ability of nonlinear optical processes to mediate and transform optical signals in a myriad of novel devices,including optical modulators,transducers,color filters,photodetectors,photon sources,and ultrafast optical *** inherent weakness of optical nonlinearities at smaller scales has,however,hindered the realization of efficient miniaturized devices,and strategies for enhancing both device efficiencies and synthesis throughput via nanoengineering remain ***,we demonstrate a novel mechanism by which second harmonic generation,a prototypical nonlinear optical phenomenon,from individual lithium niobate particles can be significantly enhanced through nonradiative coupling to the localized surface plasmon resonances of embedded gold nanoparticles.A joint experimental and theoretical investigation of single mesoporous lithium niobate particles coated with a dispersed layer of~10 nm diameter gold nanoparticles shows that a~32-fold enhancement of second harmonic generation can be achieved without introducing finely tailored radiative nanoantennas to mediate photon transfer to or from the nonlinear *** work highlights the limitations of current strategies for enhancing nonlinear optical phenomena and proposes a route through which a new class of subwavelength nonlinear optical platforms can be designed to maximize nonlinear efficiencies through near-field energy exchange.

关键词： material lithium harmonic

Progress of fundamental mechanism of formic acid decomposition and electrooxidation

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Journal of Energy Chemistry 2022年第7期31卷 292-309,I0008页

作者： Xin Liu Timo jacob Wang Gao Key Laboratory of Automobile Materials Ministry of EducationDepartment of Materials Science and Engineering Jilin UniversityChangchun 130022JilinChina Institute of Electrochemistry Ulm UniversityD-89081 UlmGermany

Formic acid(HCOOH) is considered as a promising viable fuel-cell ingredient for low temperature proton-exchange membrane fuel cells as a consequence of their high safety and energy density. As one prototype reaction, the study of HCOOH decomposition and electrooxidation is also helpful to understand the reaction mechanism of other small molecular organics. Herein, we present a comprehensive overview of HCOOH decomposition and electrooxidation in different environment conditions and analyze the reaction mechanism from both experimental and theoretical point of view. Furthermore, we discuss the known strategies for improving the performance of HCOOH decomposition and electrooxidation catalysts. Finally, this review presents a prospect for the future study of HCOOH decomposition and electrooxidation.

关键词： Electrochemical catalysis density functional theory Formic acid Spectroelectrochemistry Fuel cell