Pheromone gland extracts of the fall webworm,Hyphantria cunea(Lepidoptera:Arctiidae) were analyzed by gas chromatography(GC) and gas chromatography-mass spectrometry(GC-MS).Based on comparison of retention times and m...Pheromone gland extracts of the fall webworm,Hyphantria cunea(Lepidoptera:Arctiidae) were analyzed by gas chromatography(GC) and gas chromatography-mass spectrometry(GC-MS).Based on comparison of retention times and mass spectra of synthetic standards,four compounds were identi-fied as(9Z,12Z)-octadecadienal,(9Z,12Z,15Z)-octadecatrienal,(3Z,6Z,9S,10R)-9,10-epoxy-3,6-heneicosadiene and(3Z,6Z,9S,10R)-9,10-epoxy-1,3,6-heneicosatriene with a ratio of 2:33.6:58.4:6.Trapping tests showed that quaternary blend of these compounds was highly attractive to male H.cunea.Unitraps baited with the quaternary blend loading of 200―300 μg on a gray rubber septum were very effective for monitoring H.cunea populations.展开更多
Identifying the sex pheromone systems of local pest populations facilitates their management,especially for moth species that show significant geographic variation in sex pheromone communication.We investigated the ph...Identifying the sex pheromone systems of local pest populations facilitates their management,especially for moth species that show significant geographic variation in sex pheromone communication.We investigated the pheromone production and behavioral responses of the Asian corn borer(Ostrinia furnacalis Guenée;ACB)in Xinjiang,China.The ACB produces three compounds:(Z)-12-tetradecenyl acetate(Z12-14:Ac)and(E)-12-tetradecenyl acetate(E12-14:Ac)which are two sex pheromone compounds,and n-tetradecyl acetate(14:Ac)which has variable roles in mediating behavioral responses.The ratios of these three compounds produced in female gland are geographically distinct among different populations.Quantitative analysis of pheromone production showed that the proportions of Z12-14:Ac in the E/Z isomers(i.e.,Z and E12-14:Ac)and the proportions of 14:Ac in the ternary blend respectively averaged 60.46%(SD=5.26)and 25.00%(SD=7.37),with their probabilities normally or near-normally distributed.Trapping experiments in a cornfield indicated that deploying the E/Z isomers and the three compounds in rubber septa close to their gland ratios yielded the most captured males,while other ratios that deviated from the gland ratios showed reduced field captures.The ternary blend was significantly more attractive to males than the E/Z isomers in the field,indicating a functional role of 14:Ac as the third pheromone component used by the local population.Additionally,the dose-response test demonstrated that the application of the three compounds at dosages between 200 and 350μg attracted significantly more males compared to other dosages.Therefore,the characterization of this local ACB pheromone system provides additional information about its geographic variation and serves as a basis for optimizing the pheromone-mediated control of this pest in Xinjiang.展开更多
The Asian larch bark beetle, Ips subelongatus, is considered to be the major pest of larch within its natural range. We investigated the electrophysiological and behavioral characteristics as well as mitochondrial DNA...The Asian larch bark beetle, Ips subelongatus, is considered to be the major pest of larch within its natural range. We investigated the electrophysiological and behavioral characteristics as well as mitochondrial DNA cytochrome oxidase subunit I sequences of L subelongatus from 13 geographic populations throughout northeastern China in order to explore population divergence of aggregation pheromone responses and the extent of potential genetic divergence. Electrophysiological analyses showed that antennae of I. sube-longatus from all the six tested populations responded strongly to （S）-（-）-ipsenol （100% detection; 0.35-0.73 mV） in gas chromatography （GC）-electroantennographic detection （EAD） analyses, while its antipode, （R）-（＋）-ipsenol was antennally inactive. I. subelon- gatus populations varied in their responses to （R）-（-）- and （S）-（＋）-ipsdienol in GC-EAD analyses. Behavioral bioassays demonstrated that （S）-（-）-ipsenol alone was significantly attractive at all the tested sites, supporting its status as a key pheromone component of L subelongatus, whereas （S）-（＋）-ipsdienol was inactive alone. Adding （S）-（＋）-ipsdienol to （S）-（-）-ipsenol did not have any effect on the trap catches from some populations in Inner Mongolia. However, （S）-（＋）-ipsdienol showed a strong synergistic effect on （S）-（-）- ipsenol from several populations in Jilin and Liaoning Provinces, and a weak synergistic effect from some transition populations in Heilongjiang Province. Furthermore, 27 mito- chondrial haplotypes were found among the 13 populations （intraspecific nucleotide di- vergence, 0.1%-1.1%）. Analyses of molecular variance and haplotype networks indicated that different geographic populations have developed some genetic variation but did not form completely independent groups. From an applied point of view, a universal synthetic binary blend ofracemic ipsenol and （S）-（＋）-ipsdienol might have a potential for monitori展开更多
We study the charge trapping phenomenon that restricts the endurance of n-type ferroelectric field-effect transistors(FeFETs)with metal/ferroelectric/interlayer/Si(MFIS)gate stack structure.In order to explore the phy...We study the charge trapping phenomenon that restricts the endurance of n-type ferroelectric field-effect transistors(FeFETs)with metal/ferroelectric/interlayer/Si(MFIS)gate stack structure.In order to explore the physical mechanism of the endurance failure caused by the charge trapping effect,we first establish a model to simulate the electron trapping behavior in n-type Si FeFET.The model is based on the quantum mechanical electron tunneling theory.And then,we use the pulsed I_d-V_g method to measure the threshold voltage shift between the rising edges and falling edges of the FeFET.Our model fits the experimental data well.By fitting the model with the experimental data,we get the following conclusions.(i)During the positive operation pulse,electrons in the Si substrate are mainly trapped at the interface between the ferroelectric(FE)layer and interlayer(IL)of the FeFET gate stack by inelastic trap-assisted tunneling.(ii)Based on our model,we can get the number of electrons trapped into the gate stack during the positive operation pulse.(iii)The model can be used to evaluate trap parameters,which will help us to further understand the fatigue mechanism of FeFET.展开更多
基金Supported by the Beijing Science and Technology Program (Grant No. D0705002040391)Beijing Natural Science Foundation Program (Grant No. 6052018)
文摘Pheromone gland extracts of the fall webworm,Hyphantria cunea(Lepidoptera:Arctiidae) were analyzed by gas chromatography(GC) and gas chromatography-mass spectrometry(GC-MS).Based on comparison of retention times and mass spectra of synthetic standards,four compounds were identi-fied as(9Z,12Z)-octadecadienal,(9Z,12Z,15Z)-octadecatrienal,(3Z,6Z,9S,10R)-9,10-epoxy-3,6-heneicosadiene and(3Z,6Z,9S,10R)-9,10-epoxy-1,3,6-heneicosatriene with a ratio of 2:33.6:58.4:6.Trapping tests showed that quaternary blend of these compounds was highly attractive to male H.cunea.Unitraps baited with the quaternary blend loading of 200―300 μg on a gray rubber septum were very effective for monitoring H.cunea populations.
基金supported by grants from the Key R&D Program of the Xinjiang Autonomous Region,China(2021b02002-2)the National Natural Science Foundation of China(31960538)。
文摘Identifying the sex pheromone systems of local pest populations facilitates their management,especially for moth species that show significant geographic variation in sex pheromone communication.We investigated the pheromone production and behavioral responses of the Asian corn borer(Ostrinia furnacalis Guenée;ACB)in Xinjiang,China.The ACB produces three compounds:(Z)-12-tetradecenyl acetate(Z12-14:Ac)and(E)-12-tetradecenyl acetate(E12-14:Ac)which are two sex pheromone compounds,and n-tetradecyl acetate(14:Ac)which has variable roles in mediating behavioral responses.The ratios of these three compounds produced in female gland are geographically distinct among different populations.Quantitative analysis of pheromone production showed that the proportions of Z12-14:Ac in the E/Z isomers(i.e.,Z and E12-14:Ac)and the proportions of 14:Ac in the ternary blend respectively averaged 60.46%(SD=5.26)and 25.00%(SD=7.37),with their probabilities normally or near-normally distributed.Trapping experiments in a cornfield indicated that deploying the E/Z isomers and the three compounds in rubber septa close to their gland ratios yielded the most captured males,while other ratios that deviated from the gland ratios showed reduced field captures.The ternary blend was significantly more attractive to males than the E/Z isomers in the field,indicating a functional role of 14:Ac as the third pheromone component used by the local population.Additionally,the dose-response test demonstrated that the application of the three compounds at dosages between 200 and 350μg attracted significantly more males compared to other dosages.Therefore,the characterization of this local ACB pheromone system provides additional information about its geographic variation and serves as a basis for optimizing the pheromone-mediated control of this pest in Xinjiang.
文摘The Asian larch bark beetle, Ips subelongatus, is considered to be the major pest of larch within its natural range. We investigated the electrophysiological and behavioral characteristics as well as mitochondrial DNA cytochrome oxidase subunit I sequences of L subelongatus from 13 geographic populations throughout northeastern China in order to explore population divergence of aggregation pheromone responses and the extent of potential genetic divergence. Electrophysiological analyses showed that antennae of I. sube-longatus from all the six tested populations responded strongly to （S）-（-）-ipsenol （100% detection; 0.35-0.73 mV） in gas chromatography （GC）-electroantennographic detection （EAD） analyses, while its antipode, （R）-（＋）-ipsenol was antennally inactive. I. subelon- gatus populations varied in their responses to （R）-（-）- and （S）-（＋）-ipsdienol in GC-EAD analyses. Behavioral bioassays demonstrated that （S）-（-）-ipsenol alone was significantly attractive at all the tested sites, supporting its status as a key pheromone component of L subelongatus, whereas （S）-（＋）-ipsdienol was inactive alone. Adding （S）-（＋）-ipsdienol to （S）-（-）-ipsenol did not have any effect on the trap catches from some populations in Inner Mongolia. However, （S）-（＋）-ipsdienol showed a strong synergistic effect on （S）-（-）- ipsenol from several populations in Jilin and Liaoning Provinces, and a weak synergistic effect from some transition populations in Heilongjiang Province. Furthermore, 27 mito- chondrial haplotypes were found among the 13 populations （intraspecific nucleotide di- vergence, 0.1%-1.1%）. Analyses of molecular variance and haplotype networks indicated that different geographic populations have developed some genetic variation but did not form completely independent groups. From an applied point of view, a universal synthetic binary blend ofracemic ipsenol and （S）-（＋）-ipsdienol might have a potential for monitori
基金Project supported by the National Natural Science Foundation of China(Grant No.92264104)。
文摘We study the charge trapping phenomenon that restricts the endurance of n-type ferroelectric field-effect transistors(FeFETs)with metal/ferroelectric/interlayer/Si(MFIS)gate stack structure.In order to explore the physical mechanism of the endurance failure caused by the charge trapping effect,we first establish a model to simulate the electron trapping behavior in n-type Si FeFET.The model is based on the quantum mechanical electron tunneling theory.And then,we use the pulsed I_d-V_g method to measure the threshold voltage shift between the rising edges and falling edges of the FeFET.Our model fits the experimental data well.By fitting the model with the experimental data,we get the following conclusions.(i)During the positive operation pulse,electrons in the Si substrate are mainly trapped at the interface between the ferroelectric(FE)layer and interlayer(IL)of the FeFET gate stack by inelastic trap-assisted tunneling.(ii)Based on our model,we can get the number of electrons trapped into the gate stack during the positive operation pulse.(iii)The model can be used to evaluate trap parameters,which will help us to further understand the fatigue mechanism of FeFET.
