Background: In the classical psychological refractory period (PRP) paradigm, two stimuli are presented in brief succession, and participants are asked to make separate speeded responses to both stimuli. Due to a ce...Background: In the classical psychological refractory period (PRP) paradigm, two stimuli are presented in brief succession, and participants are asked to make separate speeded responses to both stimuli. Due to a central cognitive bottleneck, responses to the second stimulus are delayed, especially at short stimulus-onset asynchrony (SOA) between the two stimuli. Although the mechanisms of dual-task interference in the classical PRP paradigm have been extensively investigated, specific mechanisms underlying the cross-modal PRP paradigm are not well understood. In particular, it remains unknown whether the dominance of vision over audition manifests in the cross-modal PRP tasks. The present study aimed to investigate whether the visual dominance effect manifessts in the cross-modal PRP paradigm. Methods: We adapted the classical PRP paradigm by manipulating the order of a visual and an auditory task: the visual task could either precede the auditory task or vice versa, at either short or long SOAs. Twenty-five healthy participants took part in Experiment 1, and thirty-three new participants took part in Experiment 2. Reaction time and accuracy data were calculated and further analyzed by repeated-measures analysis of variance. Results: The results showed that visual precedence in the Visual-Auditory condition caused larger impairments to the subsequent auditory processing than vice versa in the Auditory-Visual condition: a larger delay of second response was revealed in the Visual-Auditory condition ( 135 ± 10 ms) than the Auditory-Visual condition (88 ± 9 ms). This effect was found only at the short SOAs tinder the existence of the central bottleneck, but not at the long SOAs. Moreover, this effect occurred both when the single visual and the single auditory task were of equal difficulty in Experiment I and when the single auditory task was more difficult than the single visual task in Experiment 2. Conclusion: Results of the two experiments suggested that the visual dominance effect 展开更多
Aims Lianas are expected to influence composition,structure and func-tioning of forest systems due to unequal distribution across the potential set of host plants.However,our understanding of mecha-nisms associated wi...Aims Lianas are expected to influence composition,structure and func-tioning of forest systems due to unequal distribution across the potential set of host plants.However,our understanding of mecha-nisms associated with preferences for specific hosts is still limited,and so is our ability to discern between endogenous and exogenous forces driving forest dynamics in the long run.In this paper,we eval-uated whether the dominant liana Hedera helix can indirectly con-tribute to the eventual dominance of the small multi-stemmed tree Corylus avellana in a remnant temperate forest in central Iberian Peninsula from comparatively reduced liana infestation on C.avel-lana relative to co-occurring woody species.Methods through principal component analysis and co-occurrence ana-lysis,we studied the distribution and spatial association between woody species and the liana H.helix.We analyzed the relationship between the number of species in a plot and the number of species infested by the liana to test the hypothesis that H.helix is a gen-eralist liana.through generalized linear mixed models,we tested the dynamic-multi-stemmed growth form of C.avellana as a plaus-ible life strategy to withstand,in the long run,the liana infestation.In particular,we tested(i)the relationship between stem size and the probability of H.helix infestation including all the tree species within plots and(ii)the relationship between stem size and mortal-ity as evidence of the stem turn over in the tree C.avellana.Important Findings Our results indicate that H.helix and C.avellana significantly co-occur in mature stands of this remnant temperate forest where pion-eer woody species are absent.Hedera helix severely infests all the woody species whenever stem size exceed≈25 cm perimeter and there is physical contact at the base of the stem.this implies that all the trees in the community are potential hosts for H.helix.Mixed models indicate that both,infestation by H.helix and stem mortality,are positively related to C.avellana stem perimeter.Reduced lon展开更多
传统多目标优化算法(Multi-objective evolution algorithms,MOEAs)的基本框架大致分为两部分:首先是收敛性保持,采用Pareto支配方法将种群分成若干非支配层;其次是分布性保持,在临界层中,采用分布性保持机制维持种群的分布性.然而在处...传统多目标优化算法(Multi-objective evolution algorithms,MOEAs)的基本框架大致分为两部分:首先是收敛性保持,采用Pareto支配方法将种群分成若干非支配层;其次是分布性保持,在临界层中,采用分布性保持机制维持种群的分布性.然而在处理高维优化问题(Many-objective optimization problems,MOPs)(目标维数大于3)时,随着目标维数的增加,种群的收敛性和分布性的冲突加剧,Pareto支配关系比较个体优劣的能力也迅速下降,此时传统的MOEA已不再适用于高维优化问题.鉴于此,本文提出了一种基于邻域竞赛的多目标优化算法(Evolutionary algorithm based on neighborhood competition for multi-objective optimization,NCEA).NCEA首先将个体的各个目标之和作为个体的收敛性估计;然后,计算当前个体向量与收敛性最好的个体向量之间的夹角,并将其作为当前个体的邻域估计;最后,通过邻域竞赛方法将问题划分为若干个相互关联的子问题并逐步优化.为了验证NCEA的有效性,本文选取5个优秀的算法与NCEA进行对比实验.通过对比实验验证,NCEA具有较强的竞争力,能同时保持良好的收敛性和分布性.展开更多
Dominance hierarchy reflects resource competition in male primates as well as females.In this study,we collected data on the social rank and mating competition of female Sichuan snub-nosed monkeys from September 2009 ...Dominance hierarchy reflects resource competition in male primates as well as females.In this study,we collected data on the social rank and mating competition of female Sichuan snub-nosed monkeys from September 2009 to June 2010 in the Qinling Mountains,Shaanxi,China.Displacement was used to determine social hierarchy of the studied wild females.A total of 1223 displacement bouts between adult females and 316 mating behaviors within one-male units(OMUs) were recorded.Competitive displacement among females was very low(0.22 displacements per observation hour).The dominant ranks of females in target OMUs were determined by displacement,from one OMU to another:JB unit:YL > DBC > YCM >XBC > BD;JZT unit:XHW > JG > DT;PK unit:QQ > TM > HF;LP unit:SK > TH > WM.Higher-ranking females performed significantly more sexual behavior than lower-ranking females in this rare monkey.High-ranking females were more likely to win mating contests within those OMUs.Based on these studies,we assessed the social relationships among adult females and clarified possible explanations for the strategies of female mating competition in the OMUs.Furthermore,the notion that reproductive success may also be related to female dominance hierarchies in this polygynous species should be considered in future research.展开更多
文摘Background: In the classical psychological refractory period (PRP) paradigm, two stimuli are presented in brief succession, and participants are asked to make separate speeded responses to both stimuli. Due to a central cognitive bottleneck, responses to the second stimulus are delayed, especially at short stimulus-onset asynchrony (SOA) between the two stimuli. Although the mechanisms of dual-task interference in the classical PRP paradigm have been extensively investigated, specific mechanisms underlying the cross-modal PRP paradigm are not well understood. In particular, it remains unknown whether the dominance of vision over audition manifests in the cross-modal PRP tasks. The present study aimed to investigate whether the visual dominance effect manifessts in the cross-modal PRP paradigm. Methods: We adapted the classical PRP paradigm by manipulating the order of a visual and an auditory task: the visual task could either precede the auditory task or vice versa, at either short or long SOAs. Twenty-five healthy participants took part in Experiment 1, and thirty-three new participants took part in Experiment 2. Reaction time and accuracy data were calculated and further analyzed by repeated-measures analysis of variance. Results: The results showed that visual precedence in the Visual-Auditory condition caused larger impairments to the subsequent auditory processing than vice versa in the Auditory-Visual condition: a larger delay of second response was revealed in the Visual-Auditory condition ( 135 ± 10 ms) than the Auditory-Visual condition (88 ± 9 ms). This effect was found only at the short SOAs tinder the existence of the central bottleneck, but not at the long SOAs. Moreover, this effect occurred both when the single visual and the single auditory task were of equal difficulty in Experiment I and when the single auditory task was more difficult than the single visual task in Experiment 2. Conclusion: Results of the two experiments suggested that the visual dominance effect
基金J.M.G.was granted with a Postdoctoral Fellowship at the University of Alcalá.E.G.thanks support of FONDECYT grant 1140070The last sampling period was funded by the FUNDIVER project(MINECO:CGL2015-69186-C2-2-R).
文摘Aims Lianas are expected to influence composition,structure and func-tioning of forest systems due to unequal distribution across the potential set of host plants.However,our understanding of mecha-nisms associated with preferences for specific hosts is still limited,and so is our ability to discern between endogenous and exogenous forces driving forest dynamics in the long run.In this paper,we eval-uated whether the dominant liana Hedera helix can indirectly con-tribute to the eventual dominance of the small multi-stemmed tree Corylus avellana in a remnant temperate forest in central Iberian Peninsula from comparatively reduced liana infestation on C.avel-lana relative to co-occurring woody species.Methods through principal component analysis and co-occurrence ana-lysis,we studied the distribution and spatial association between woody species and the liana H.helix.We analyzed the relationship between the number of species in a plot and the number of species infested by the liana to test the hypothesis that H.helix is a gen-eralist liana.through generalized linear mixed models,we tested the dynamic-multi-stemmed growth form of C.avellana as a plaus-ible life strategy to withstand,in the long run,the liana infestation.In particular,we tested(i)the relationship between stem size and the probability of H.helix infestation including all the tree species within plots and(ii)the relationship between stem size and mortal-ity as evidence of the stem turn over in the tree C.avellana.Important Findings Our results indicate that H.helix and C.avellana significantly co-occur in mature stands of this remnant temperate forest where pion-eer woody species are absent.Hedera helix severely infests all the woody species whenever stem size exceed≈25 cm perimeter and there is physical contact at the base of the stem.this implies that all the trees in the community are potential hosts for H.helix.Mixed models indicate that both,infestation by H.helix and stem mortality,are positively related to C.avellana stem perimeter.Reduced lon
文摘传统多目标优化算法(Multi-objective evolution algorithms,MOEAs)的基本框架大致分为两部分:首先是收敛性保持,采用Pareto支配方法将种群分成若干非支配层;其次是分布性保持,在临界层中,采用分布性保持机制维持种群的分布性.然而在处理高维优化问题(Many-objective optimization problems,MOPs)(目标维数大于3)时,随着目标维数的增加,种群的收敛性和分布性的冲突加剧,Pareto支配关系比较个体优劣的能力也迅速下降,此时传统的MOEA已不再适用于高维优化问题.鉴于此,本文提出了一种基于邻域竞赛的多目标优化算法(Evolutionary algorithm based on neighborhood competition for multi-objective optimization,NCEA).NCEA首先将个体的各个目标之和作为个体的收敛性估计;然后,计算当前个体向量与收敛性最好的个体向量之间的夹角,并将其作为当前个体的邻域估计;最后,通过邻域竞赛方法将问题划分为若干个相互关联的子问题并逐步优化.为了验证NCEA的有效性,本文选取5个优秀的算法与NCEA进行对比实验.通过对比实验验证,NCEA具有较强的竞争力,能同时保持良好的收敛性和分布性.
基金supported by the Key Program of National Natural Science Foundation of China (31130061)National Natural Science Foundation of China (30970444,30970168,30970379)+4 种基金Special Foundation of Shaanxi Academy of Sciences,China (2010K-01)Western Light Talent Culture Project (2011DF05)Research Fund for the Doctoral Program of Higher Education of China (20106101110005)Natural Science Foundation of Shaanxi Province China (2010JM3006)Cosmo Oil Eco Card Fund of Japan (2005-2012)
文摘Dominance hierarchy reflects resource competition in male primates as well as females.In this study,we collected data on the social rank and mating competition of female Sichuan snub-nosed monkeys from September 2009 to June 2010 in the Qinling Mountains,Shaanxi,China.Displacement was used to determine social hierarchy of the studied wild females.A total of 1223 displacement bouts between adult females and 316 mating behaviors within one-male units(OMUs) were recorded.Competitive displacement among females was very low(0.22 displacements per observation hour).The dominant ranks of females in target OMUs were determined by displacement,from one OMU to another:JB unit:YL > DBC > YCM >XBC > BD;JZT unit:XHW > JG > DT;PK unit:QQ > TM > HF;LP unit:SK > TH > WM.Higher-ranking females performed significantly more sexual behavior than lower-ranking females in this rare monkey.High-ranking females were more likely to win mating contests within those OMUs.Based on these studies,we assessed the social relationships among adult females and clarified possible explanations for the strategies of female mating competition in the OMUs.Furthermore,the notion that reproductive success may also be related to female dominance hierarchies in this polygynous species should be considered in future research.