Cherry Bark Tortrix, Enarmonia formosana: Olfactory Recognition of and Behavioral Deterrence by Nonhost Angio- and Gymnosperm Volatiles

We tested the hypothesis that males and females of the cherry bark tortrix (CBT), Enarmonia formosana, antennally perceive and behaviorally respond to volatiles from nonhost plants. Volatiles from flowering cherry trees, Prunus serrulata Kwanzan, and from nonhost trees, including trembling aspen, Populus tremuloides, grand fir, Abies grandis, Norway spruce, Picea abies, and Scots pine, Pinus sylvestris, were captured on Porapak Q and extracts analyzed by coupled gas chromatographic–electroantennographic detection (GC-EAD). Compounds that elicited responses from male and female antennae were identified by coupled GC–mass spectrometry (MS) and by comparative GC-MS and GC-EAD with authentic standards. In field cage and field experiments, nonanal from aspen trees and (±)--pinene from coniferous trees were effective in reducing captures of male CBT in pheromone-baited traps and deterring oviposition by female CBT on cherry blocks. Recognition of nonhost volatiles, such as nonanal and -pinene, may allow male and/or female CBT to avoid trees that provide inadequate concealment from predators during calling, resting, and copulation and that are unsuitable for oviposition and development of offspring. Nonhost volatiles may also be exploited for control of CBT by disrupting both mate- and host-finding.     

Host marking pheromone ofRhagoletis cerasi: Foraging behavior in response to synthetic pheromonal isomers

We studied the foraging behavior ofRhagoletis cerasi females in trees treated with synthetic cherry fruit fly host marking pheromone (HMP) under seminatural conditions (potted trees enclosed in a screen cage). Results show that synthetic HMP (particularly the 8RS-@#@ 15R isomer configuration (racemic mixture)) was highly effective in eliciting behavioral responses similar to those reported in studies using natural HMP. Flies exposed to synthetic pheromone exhibited short tree residence times (i.e., emigrated faster), increased flight frequency rates (measured as number of alightings per/minute), higher irritation indices while on a tree or a fruit, and oviposited fewer eggs per fruit visit than flies exposed to clean trees and fruit (not treated with synthetic HMP). Furthermore, we provide evidence showing that when flies were continuously exposed to an HMP-saturated environment, they exhibited an increased tendency to lay eggs in marked fruit.     

自适应双向菌群优化算法

提出了自适应双向菌群优化算法,应用聚类思想将趋化步长进行自适应调整,提高算法的局部搜索能力,引入双向游动机制,提高了算法的搜索效率和速度。针对10个复杂Benchmark函数进行了数值优化实验,其结果表明,在所有测试函数中,该算法在搜索能力和稳定性等方面优于其他典型算法的比率达到60%～90%,验证了算法的有效性。     

基于细菌觅食算法的SAR图像阈值分割

提出了一种SAR图像阈值分割新方法.该方法在深入分析基本细菌觅食算法的基础上,缩小菌群的觅食空间以进一步提高分割阈值的搜索速度,然后采用改进的二维灰熵模型作为细菌觅食算法的适应度函数,通过菌群的趋化、复制和驱散3种行为模式并行搜索最佳阈值.实验结果初步显示,该方法在收敛速度、稳定性和分割效果3个方面,均优于基于遗传算法、人工鱼群算法等群体智能优化算法的分割方法.     

Foraging mode and evolution of strike-induced chemosensory searching in lizards

Strike-induced chemosensory searching (SICS) in lizards and snakes is a means of relocating prey by scent-trailing. The two main components of SICS are an elevated tongue-flick rate for vomerolfactory sampling after biting prey (PETF) and searching movements. In combination, these behaviors permit scent-trailing. Prey chemical discrimination, which is a prerequisite for SICS, is present in active foragers, but not in ambush foragers. Using comparative data, I show that searching movements and SICS have undergone correlated evolution with foraging mode and with prey chemical discrimination in lizards. This suggests that active foraging selects for prey chemical discrimination, which is then employed to search for escaped prey using the typical movements and tongue-flicking behaviors of active foragers. SICS in lizards is simply heightened active foraging after biting prey. In nonvenomous snakes, SICS is similar to that in lizards but is not restricted to active foragers. Only highly venomous snakes voluntarily release dangerous prey upon envenomation, pause to let the venom incapacitate the prey, and then relocate the prey by scent-trailing. PETF was observed in two ambush foragers and is not evolutionarily correlated with foraging mode or searching movements. Because it occurs in species lacking prey chemical discrimination, such PETF may be a response to gustatory cues or to internal chemicals not encountered on surfaces or trails of uninjured prey.     

基于改进细菌觅食的协作学习分组算法

针对协作学习中基于学习者特征的分组方式对学习过程的影响,设计一种基于改进细菌觅食的协作学习分组算法。在实现协作学习分组过程中,引入分组调节因子和特征权值,满足不同教学活动对学习者多个特征及分组的要求。为构成有效的分组空间,在细菌种群初始化中,细菌群体以实数编码,并加入随机扰动以增加细菌种群的多样性;在算法后期加入二次变异操作,以避免细菌觅食算法可能出现的早熟收敛现象。仿真实验结果表明,该算法在不同分组形式下,与传统算法相比,具有较优的分组性能和较高的准确率,并且对于不同数据集规模具有良好的稳定性。     

Can social bees be influenced to choose a specific feeding station by adding the scent of the station to the hive air?

The behavioral response of honeybees (Apis mellifera L.) and bumblebees (Bombus terrestris L.) to the flower volatiles 2-ethyl-1-hexanol and myrcene isolated in situ from white clover (Trifolium repens L.) and oil seed rape (Brassica napus oleifera), respectively, were investigated on a rotating arena with 12 visually identical, but differently scented, feeding stations. When locating a feeding station, neutral in both shape and color, foragers used scent as orientation cue. Introduction of 2-ethyl-1-hexanol to the honeybee hives induced significantly more visits to sites containing this compound. In contrast, introduction of myrcene to the hives did not influence the foraging choices of honeybees significantly. No effect of hive scent composition on the choices made by bumblebees could be detected. Experienced bumble bees, i.e., bees with more than five visits to the feeding stations, tended to visit a particular position on the arena without discriminating between the two volatiles. In contrast, honeybees showed no positioning behavior on the arena, using primarily odoriferous stimuli. The observed influences of addition of scents to the hives are discussed in relation to the general knowledge on foraging behavior of social bees and the emission of volatiles from leaves and flowers.     

Role of prey odor in food recognition by rock crabs,Cancer irroratus say

Rock crabs,Cancer irroratus, respond to food odors in low concentration as measured by changes in antennular flicking rate. The responses of rock crabs to prey odor were tested in the presence and absence of visual cues to determine the role of chemical cues in prey recognition. Crabs were attracted to the source of mussel odor introduced into one arm of a Y maze. Natural and artificial prey shells and resin boxes were presented to crabs with and without the presence of mussel extract. The crabs were able to see, handle, and manipulate these objects. Crabs opened and consumed contents that emitted chemosensory cues and ignored identical objects that did not. Rock crabs were attracted to food odors and are capable of utilizing chemical cues to detect, locate, and identify food items.     

Role of trail pheromone in foraging and processionary behavior of pine processionary caterpillars Thaumetopoea pityocampa

Although caterpillars of Thaumetopoea pityocampa may mark their pathways with silk, this study shows that the material is essential to neither the elicitation nor maintenance of trail-following or processionary behavior. Trail following is dependent upon a pheromone the caterpillars deposit by brushing the ventral surfaces of the tips of their abdomens against the substrate. Earlier instars are strongly bound to their trail system; in the laboratory, caterpillars followed circular trails continuously for as long as 12 hr before breaking away from them. The trail pheromone is long-lived and soluble in nonpolar solvents, but its volatilization or degradation allows the caterpillars to distinguish new from aged trails. In contrast to trail following, processionary behavior, the head-to-tail, single-file movement of the caterpillars is dependent on neither silk nor the trail pheromone. Stimuli associated with setae found on the tip of the abdomen of the precedent caterpillar serve to hold processions together, and such stimuli take priority over those associated with either the trail pheromone or silk. Although the caterpillars discern trail strength and choose stronger over weaker trails, the trail marking system of the processionary caterpillar appears less sophisticated than those of other, previously studied species of social caterpillars, and colonies are relatively inefficient in abandoning exhausted feeding sites in favor of new food finds. In laboratory studies, females were more likely to lead processions than males, and leaders, regardless of gender, expended more energy in locomotion than followers.     

Hybrid BFOA–PSO algorithm for automatic generation control of linear and nonlinear interconnected power systems

In the bacteria foraging optimization algorithm (BFAO), the chemotactic process is randomly set, imposing that the bacteria swarm together and keep a safe distance from each other. In hybrid bacteria foraging optimization algorithm and particle swarm optimization (hBFOA–PSO) algorithm the principle of swarming is introduced in the framework of BFAO. The hBFOA–PSO algorithm is based on the adjustment of each bacterium position according to the neighborhood environment. In this paper, the effectiveness of the hBFOA–PSO algorithm has been tested for automatic generation control (AGC) of an interconnected power system. A widely used linear model of two area non-reheat thermal system equipped with proportional-integral (PI) controller is considered initially for the design and analysis purpose. At first, a conventional integral time multiply absolute error (ITAE) based objective function is considered and the performance of hBFOA–PSO algorithm is compared with PSO, BFOA and GA. Further a modified objective function using ITAE, damping ratio of dominant eigenvalues and settling time with appropriate weight coefficients is proposed to increase the performance of the controller. Further, robustness analysis is carried out by varying the operating load condition and time constants of speed governor, turbine, tie-line power in the range of +50% to ?50% as well as size and position of step load perturbation to demonstrate the robustness of the proposed hBFOA–PSO optimized PI controller. The proposed approach is also extended to a non-linear power system model by considering the effect of governor dead band non-linearity and the superiority of the proposed approach is shown by comparing the results of craziness based particle swarm optimization (CRAZYPSO) approach for the identical interconnected power system. Finally, the study is extended to a three area system considering both thermal and hydro units with different PI coefficients and comparison between ANFIS and proposed approach has been provided.