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This work focuses on the effects of ultrasonic shot peening (USP) on grain refinement and orientation behavior in the surface region of GH4151 superalloy. The microstructure evolution of the alloy under USP durations were studied. The effects of USP-induced grain refinement, orientation, and dislocation motion behavior were analyzed. The results indicated that during the USP process, the plastic deformation of the surface layer of superalloys is accompanied by changes in grain size and orientation. The random impact of the spheres on the surface area promotes grain refinement and grain rotation, enhancing the randomness of grain orientations and reducing the texture strength and the proportion of "soft" orientation distribution. Over a long period of treatment, a large number of spheres cause the slip planes and slip directions of each grain to rotate due to the additional shear stress from the impact, resulting in relatively consistent plastic deformation on the surface and the enhanced randomness of grain orientations, thus reducing the high texture strength introduced by previous machining processes. The understanding of dislocation pile-up behavior and the relationship between externally applied shear stress, pile-up characteristics, and grain refinement is essential for optimizing the USP process and achieving the desired material properties. [ABSTRACT FROM AUTHOR]

BACKGROUND: Push‐pull with semiochemicals in pest management uses repellents to reduce response of pests to food‐mate resources (push) and attractive traps to reduce populations (pull). Simulation models of push‐pull can aid understanding of plant‐insect interactions in nature and suggest hypotheses for field tests that improve management. A previous model indicated advantages of push‐pull for controlling ambrosia beetle, Euwallacea fornicatus, pest of avocado trees. However, the simulated behavior of repellency was inconsistent with field observations. RESULTS: We simulated individual‐based movement of insects in push‐pull to reveal relationships between parameters of radii (strength) of attractive traps, pest aggregations, and repellents with densities of each in an avocado orchard to visualize and understand the interactions and significance. Simulations indicated placement of traps along a 1‐ha area periphery as a barrier resulted in similar trapping and mating as when traps were in a grid, either when insects originated randomly inside the plot or came from outside the plot. However, when insects originated from outside, both arrangements caught slightly more than when insects originated within the plot. CONCLUSION: There were no differences in capture rates whether traps were spaced in a barrier along the plot's periphery or in a grid covering the plot. Push‐pull was more effective than pull (mass trapping) alone. Repellent behavior of individuals when encountering a repellent radius was modelled by approximate 90° turns (right or left at random) when about to enter an infestation, consistent with earlier observations of effects of repellents on bark beetles orienting to aggregation pheromone. © 2022 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Every year, billions of animals leave their home range and start seasonal migrations in order to find more favorable resources and to escape harsh environmental conditions. These round trips often span thousands of kilometers. To successfully navigate along their route, animals rely on various external references. While landmarks and celestial cues like stars or the sun are easy to imagine as guidance on these journeys, using the geomagnetic field for orientation is more elusive. The geomagnetic field is an omnipresent cue, which can be sensed and relied upon by many animals, even when visual cues are sparse. How magnetic fields can be perceived seems to vary between birds and fish. While birds seem to use a mechanism based on the quantum mechanical properties of electron spins, fish may have evolved a compass similar in its function to the technical devises developed by humans. How these mechanisms work precisely and how they are integrated are research questions addressed in SFB 1372. [ABSTRACT FROM AUTHOR]

Polyacrylonitrile (PAN) precursors with different orientation behaviors were prepared by changing the coagulation bath conditions such as concentration and temperature. The orientation structure of the PAN precursor was determined by the method of sound velocity. X-ray diffraction and optical microscopy were used to investigate the crystalline structure and morphological characterization of nascent fiber, and the correlation between orientation of precursor and structure of nascent fiber was established. The molecular chain orientation ability “a” was defined as the slope of the logarithmic fitting curve of the degree of orientation varying with the drafting ratio, and the relationship between “a” and the crystallinity of nascent fiber was studied. The results show that the higher crystallinity nascent fiber has, the lower drawing ability PAN precursor has, and the higher degree of orientation has under the same drafting ratios. The maximum drafting factor of polyacrylonitrile precursor is significantly affected by radial structure of nascent fiber, it reaches the local maximum when the coagulation bath concentration is 74%. The fiber with high solvent content has higher molecular chain orientation ability than the fiber with low solvent content. The molecular chain orientation ability of precursor increases with the crystallinity of nascent fiber.

Early in evolution, the ability to sense and respond to changing environments must have provided a critical survival advantage to living organisms. From bacteria and worms to flies and vertebrates, sophisticated mechanisms have evolved to enhance odor detection and localization. Here, we review several modes of chemotaxis. We further consider the relevance of a striking and recurrent motif in the organization of invertebrate and vertebrate sensory systems, namely the existence of two symmetrical olfactory sensors. By combining our current knowledge about the olfactory circuits of larval and adult Drosophila, we examine the molecular and neural mechanisms underlying robust olfactory perception and extend these analyses to recent behavioral studies addressing the relevance and function of bilateral olfactory input for gradient detection. Finally, using a comparative theoretical approach based on Braitenberg's vehicles, we speculate about the relationships between anatomy, circuit architecture and stereotypical orientation behaviors.

BACKGROUND (E)‐4,8‐dimethylnona‐1,3,7‐triene (DMNT), one of the homoterpenes, is thought to contribute to plant indirect defense against insect herbivores. DMNT‐enriched plants have great application potential to regulate insect behavior in the 'push & pull' strategy of pest management. However, de novo biosynthesis of DMNT in plants without a homoterpene metabolic pathway in their wild type is still not achieved, and the role of DMNT played in these plants and their interacted insects remains unclear. RESULTS: Cytochrome P450s and terpene synthases involved in homoterpenes biosynthesis in cotton plants were employed to generate DMNT‐releasing tobacco plants. Single GhTPS14 transgenic Nicotiana tabacum only emitted (E)‐nerolidol, the precursor of DMNT. Transgenic tobaccos expressing single GhCYP82Ls were unable to produce DMNT or TMTT, while DMNT was detected when exogenous (E)‐nerolidol was added. Compared to wild‐type plants, only co‐expression of GhCYP82Ls and GhTPS14 in transgenic tobaccos triggered the constitutive release of single‐component DMNT. Furthermore, DMNT‐emitting transgenic tobacco plants, whether infested with Helicoverpa armigera larvae or not, significantly incited orientation behavior of parasitoid wasps Microplitis mediator. CONCLUSION: Wild type N. tabacum plants have no DMNT metabolic pathway. DMNT could be de novo biosynthesized via co‐expression of GhCYP82Ls and GhTPS14. What is more, the parasitoid wasp M. mediator could be recruited by DMNT‐releasing transgenic tobaccos, especially by H. armigera‐infested transgenic tobaccos, suggesting the potential roles of engineered N. tabacum in regulating the behavioral preference of M. mediator. [ABSTRACT FROM AUTHOR]

In this study, we determine the strain rate and temperature-dependent mechanical material behavior as well as the glass transition temperature and coefficient of thermal expansion of polyethylene melts using molecular dynamics simulation. In order to achieve realistic chain lengths polyethylene was simulated by three different coarse-grained models of various bead sizes. All simulations are performed by using the simulation package ESPResSo++, which we extended with a regulation procedure for the simulation of tensile tests on the micro-scale. The process-relevant observables, such as the elastic modulus, yield stress, and Poisson's ratio are investigated at the meso-level. The chain orientation and entanglement behavior show effects that precisely illuminate the experimental stress strain response, giving important hints for production process control. Summarized, we are able to successfully reproduce the characteristic stress strain response for polyethylene as observed in experiments. Thus, we establish a closer link between microscopic and macroscopic system descriptions in order to provide a deeper understanding of material properties in their production process, i.e. for changing external conditions. [ABSTRACT FROM AUTHOR]

Echolocating bats emit biosonar calls and use echoes arising from call reflections, for orientation. They often pattern their calls into groups which increases the rate of sensory feedback. Insectivorous bats emit call groups at a higher rate when orienting in cluttered compared to uncluttered environments. Frugivorous bats increase the rate of call group emission when they echolocate in noisy environments. In frugivorous bats, it remains unclear if call group emission represents an exclusive adaptation to avoid acoustic interference by signals of conspecifics or if it represents an adaptation that allows to orient under demanding environmental conditions. Here, we compared the emission pattern of the frugivorous bat Carolliaperspicillata when the bats were flying in narrow versus wide or cluttered versus non-cluttered corridors. The bats emitted larger call groups and they increased the call rate within call groups when navigating in narrow or cluttered environments. These adaptations resemble the ones shown when the bats navigate in noisy environments. Thus, call group emission represents an adaptive behavior when the bats orient in complex environments. [ABSTRACT FROM AUTHOR]

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Copyright of Chinese Journal of Applied Entomology is the property of Chinese Journal of Applied Entomology, Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Insects communicating with pheromones, be it sex- or aggregation pheromones, are confronted with an olfactory environment rich in a diversity of volatile organic compounds of which plants are the main releaser. Certain of these volatiles can represent behaviorally relevant information, such as indications about host- or non-host plants; others will provide essentially a rich odor background out of which the behaviorally relevant information needs to be extracted. In an attempt to disentangle mechanisms of pheromone communication in a rich olfactory environment, which might underlie interactions between intraspecific signals and a background, we will summarize recent literature on pheromone/plant volatile interactions. Starting from molecular mechanisms, describing the peripheral detection and central nervous integration of pheromone-plant volatile mixtures, we will end with behavioral output in response to such mixtures and its plasticity.

Two species, the cigarette beetle Lasioderma serricome (F.) and the drugstore beetle Stegobium paniceum (L.), are particularly important stored-product pests because they damage dry food. A previous study showed that L. serricome adults are attracted more to ultraviolet (UV) and blue light wave ranges more than others such as turquoise, green, yellow, red, and warm white. However, the previous study did not equalize the amounts of light. The study also evaluated the attractiveness by the numbers of L. serricome individuals that were lured to LED lights in a small box in the laboratory. In some storehouses, damage by S. paniceum is more serious and establishment of an effective monitoring tool is required. Therefore, in the present study, attractions of these beetles to UV and blue light traps were compared to develop a tool to monitor the beetle pests. First, adult L. serricome and S. paniceum beetles were provided with UV- and blue-LED panels whose light intensities were equalized in the laboratory, and the walking and flying paths of each adult were recorded and measured. As a result, adults were clearly attracted to the side of UV-LED panel by walking compared to the blue one. Second, we compared the numbers of cigarette beetles collected by sticky sheets that were set in the back of UV or bluelight LED traps in a real storehouse. The results showed that these beetles were significantly more attracted to UV than blue-light LED traps, indicating the UV-LED trap is a powerful tool to monitor these two pest species. [ABSTRACT FROM AUTHOR]

Cyrtorhinus lividipennis Reuter, an important predator of rice planthopper and leafhoppers, plays a significant role in the integrated pest management (IPM) of rice pest. However, chemical control remains a major strategy against rice pests. Insecticide risk assessment should include sublethal effects on non-target organisms before being included in IPM schemes. We examined the sublethal effects of four insecticides, triazophos, deltamethrin, chlorantraniliprole, and pymetrozine on C. lividipennis. The results demonstrated that sublethal concentrations of deltamethrin (LC and LC) disrupted the orientation behavior of C. lividipennis, but sublethal concentrations of triazophos (LC and LC), chlorantraniliprole, and pymetrozine (the recommended field rate and half field rate) had no impact on the behavioral response of surviving predators. The mean consumption of C. lividipennis treated with sublethal concentrations of triazophos decreased approximately 18-35 % compared to that of untreated ones. Sublethal concentrations of deltamethrin also reduced the mean consumption of C. lividipennis, but sublethal concentrations of chlorantraniliprole and pymetrozine exhibited no influence on the predatory capability of the predator. Significant reductions in pepsin activity were observed in triazophos and deltamethrin treatments but not in chlorantraniliprole and pymetrozine treatments. Our results indicated that triazophos and deltamethrin exerted sublethal effects, such as disturbed foraging ability, reduced predatory capacity, and decreased pepsin activity on C. lividipennis, and chlorantraniliprole and pymetrozine were regarded as safer to this predator. [ABSTRACT FROM AUTHOR]

The analysis of animal movements may help to understand orientation strategies. While there have been many studies on sandhoppers’ orientation mechanisms through the analysis of their orientation angles, no attempts have been made to analyze individual tracks under (varying) natural conditions. The species Talitrus saltator (Montagu, 1808) has the ability to recover the optimal zone of the beach at or below the drift-line and burrow into moist sand when released in the upper beach during the day. On dry sand sandhoppers typically jump and leave tracks; we measured the tracks in relation to the starting point. For each track we calculated: the mean angle of direction, distance covered from the starting point, number of jumps, number of effective turnings, rectilinearity and efficiency (how well the track was directed to the goal). We proposed a classification of the tracks based on both rectilinearity and efficiency. Freshly collected adult individuals from the population of San Rossore beach (Pisa, Italy) were compared to laboratory-born ones so as to highlight eventual differences related to experience. Most of the wild individuals made tracks with high rectilinearity and efficiency. This good orientation suggests that these individuals had developed experience of their beach rapidly recovering the optimal zone. Laboratory-born individuals showed a higher scatter in orientation and winding tracks. The factors that influenced the individuals during their movements could also be inferred by the track course. In addition to the sun azimuth (sun compass), wind direction appeared to be a major factor influencing orientation. The individuals released with onshore winds were more efficiently oriented seawards than those released with winds from other directions. [ABSTRACT FROM AUTHOR]

The effects of interactions between nano-SiO2 and polyurethane segments on structure and orientation behaviors in shape memory process have been systematically investigated. Polyurethane (PU)/nano-SiO2 composites were prepared by solution mixing in tetrahydrofuran (THF). The scanning electron microscopy (SEM) observation shows that nano-SiO2 particles are well dispersed in PU matrix. Besides the shape memory performance of pure PU is superior to that of PU/nano-SiO2 composite with 3 wt% filler content. It has been proved that the nano-SiO2 has some interaction with the segments of PU, affecting the orientation behaviors of polyurethane in both drawing and recovery process. In the drawing process, the hard segments at the domain interface and soft segments of PU-3% have a perpendicular direction at the small strain, and then possess a parallel orientation at larger deformation, whereas those of PU-0% orient positively from the beginning to the end. Moreover, the mobility of both soft and hard segments is retarded mostly by the nano-SiO2. In addition, differential scanning calorimetry (DSC) and wide-angle X-ray diffraction (WAXD) tests have also been done. The results indicate that crystallization is quite small influenced by the addition of nano-SiO2. [ABSTRACT FROM AUTHOR]

Insects communicating with pheromones, be it sex- or aggregation pheromones, are confronted with an olfactory environment rich in a diversity of volatile organic compounds of which plants are the main releaser. Certain of these volatiles can represent behaviorally relevant information, such as indications about host- or non-host plants; others will provide essentially a rich odor background out of which the behaviorally relevant information needs to be extracted. In an attempt to disentangle mechanisms of pheromone communication in a rich olfactory environment, which might underlie interactions between intraspecific signals and a background, we will summarize recent literature on pheromone/plant volatile interactions. Starting from molecular mechanisms, describing the peripheral detection and central nervous integration of pheromone-plant volatile mixtures, we will end with behavioral output in response to such mixtures and its plasticity. [ABSTRACT FROM AUTHOR]

Early in evolution, the ability to sense and respond to changing environments must have provided a critical survival advantage to living organisms. From bacteria and worms to flies and vertebrates, sophisticated mechanisms have evolved to enhance odor detection and localization. Here, we review several modes of chemotaxis. We further consider the relevance of a striking and recurrent motif in the organization of invertebrate and vertebrate sensory systems, namely the existence of two symmetrical olfactory sensors. By combining our current knowledge about the olfactory circuits of larval and adult Drosophila, we examine the molecular and neural mechanisms underlying robust olfactory perception and extend these analyses to recent behavioral studies addressing the relevance and function of bilateral olfactory input for gradient detection. Finally, using a comparative theoretical approach based on Braitenberg’s vehicles, we speculate about the relationships between anatomy, circuit architecture and stereotypical orientation behaviors.

The article discusses a study that examined what factors determine songbird migratory routes in the U.S. It states that these birds have two choices when they travel, a shorter but more dangerous route over water, since they cannot land and rest, and a longer, but safer route over land. To determine what influences their decision, it reports that researchers measured their stores of fat, levels of triglycerides, and same day changes within their body. It was discovered that energetic condition, the amount of fat they had, was the deciding factor.

The ability of ducks to derive magnetic direction information was tested in a conditioned procedure and the functional properties of the mechanism of magnetoreception investigated using common manipulations. Twelve ducks were trained to find a hidden imprinting stimulus behind one of three screens in a round arena. Once a criterion was reached, the directional choices of ducks were recorded in four treatments presented in a random order, separated with rewarded training trials to avoid extinction. In tests in the geomagnetic field, ducks preferred the screen in the training direction (P=0.005). In the crucial tests of magnetic orientation with the magnetic field experimentally shifted by 120 deg, ducks showed a significant difference in the choice for the correct magnetic direction between treatments (P=0.002). More specifically, they chose the correct magnetic direction more often than expected by chance (P=0.03), indicating that they were deriving directional information from the magnetic field. Ducks also chose the correct magnetic direction more often than expected by chance in tests with the shifted field after the upper bill was anaesthetised with lignocaine (P=0.05) or when the right eye was covered (P=0.005), indicating that these manipulations did not impair the ability to choose the correct magnetic direction. Thus, Pekin ducks can be conditioned to magnetic directions, and the results are consistent with the hypothesis that magnetic orientation is based on a chemical magnetoreception mechanism that is not restricted to the right eye. [ABSTRACT FROM AUTHOR]

Anagrus nilaparvatae (Pang et Wang) (Hymenoptera: Mymaridae), is an egg parasitoid of rice planthoppers, Nilaparvata lugens (Stål) (Homoptera: Delphacidae). This study evaluated effects of the insecticide imidacloprid on orientation behavior and parasitizing capacity of A. nilaparvatae. Sub-lethal concentrations of imidacloprid (LC20 and LC10) disrupted the foraging ability of A. nilaparvatae exposed to imidacloprid through contact or oral routes . Some survivors did not respond to volatiles from N. lugens-infested plants. Responsive individuals were equally attracted to volatiles from N. lugens-infested and healthy plants. Volatiles emitted from rice plants treated with a low concentration of imidacloprid were more attractive to A. nilaparvatae than those from plants treated with a high concentration of imidacloprid. Parasitism of N. lugens by A. nilaparvatae that survived contact with sub-lethal concentrations of imidacloprid did not decrease significantly. When A. nilaparvatae were fed imidacloprid-honey mixture, parasitism rates were 1.49% and 0%, respectively, significantly lower than those of the control (9.58%). Parasitism of N. lugens eggs in high concentration of imidacloprid treated rice plants by A. nilaparvatae decreased significantly. These effects involving disturbed foraging ability and reduced parasitizing capacity of A. nilaparvatae indicated that imidacloprid could decrease the performance of this parasitoid. [ABSTRACT FROM AUTHOR]

Polarizing films doped with three kinds of dichroic azo dyes were prepared to investigate the effect of dye structures on the orientation behavior of dyes in stretched poly(vinyl alcohol) films. One reactive group exerted an unfavorable influence on the alignment of dye molecules toward the polymer segments orientation. However, two reactive groups resulted in the effective alignment and showed the best optical properties among three kinds of dyes. [ABSTRACT FROM AUTHOR]

Abstract: Negative geotaxis, an automatic, reliable, stimulus-bound, orientation and movement directionally against gravitational cues, is often used for behavioral assessments of infant rodents. We summarize historical and contemporary analyses and conclude that negative geotaxis does not exist in infant rats. Infant rodents placed on inclined surfaces (ranging from 15° to 70° in most tests) are posturally unstable and their compensatory responses have been misinterpreted as negative geotaxis. In fact, recent findings suggest that if infant rats display a geotaxis, they show positive geotaxis on shallow angles of inclination (e.g., 4° and 8°). There may be utility in assessing postures and motoric responses of infant rats on relatively robust angles of inclination, but these are not tests of negative geotaxis. [Copyright &y& Elsevier]

Two experiments were carried out with Mongolian gerbils to determine the roles of optic tectum and visual cortex in the mediation of visually guided head turns and locomotion elicited and controlled by discrete visual targets. In Experiment 1, the behavior of animals with either a sham operation, a bilateral lesion of optic tectum, or a bilateral ablation of areas 17, 18a, and 18b was recorded on videotape as they ran from the center of a circular arena toward a small visual target projected in different locations around the perimeter of the arena. The amplitude and direction of the head turns and the accuracy of their locomotor responses were reconstructed from a frame by frame analysis of the videotapes. Sham-operate gerbils made a series of head turns before running accurately and efficiently toward the target. The gerbils with lesions of areas 17, 18a, and 18b rarely made more than one head turn before running toward the perimeter of the arena. Although the single head turn they did make was often well-correlated with the position of the target in their visual field, the direction of their locomotor response was largely determined by the direction and amplitude of that head turn. As a consequence, these animals undershot the target more often than did the sham-operate animals, and even ran into the visual half field opposite the target if their head turn had also been made into that half field. Unlike the sham operates, these animals were unable to make further adjustments in their orientation toward the stimulus after their initial head turn. The head turns and locomotor behavior of the gerbils with lesions of optic tectum were even more disorganized and inaccurate than those of the posterior decorticates. Nevertheless, when the target was presented within 45° from their visual midline, their head turns and locomotor responses showed a systematic relationship with the eccentricity of the target. Their behavior to stimuli outside this central wedge of their visual field was completely disorganized and showed no relationship to the location of the target. In Experiment 2, unilateral lesions of area 17 were performed in the gerbils that had already received bilateral tectal lesions to determine whether such lesions would affect the 'residual' ability of these animals to orient toward stimuli located within the central portion of their visual field. During retesting, these animals were able to respond to targets only if they were located in the central portion of the field ipsilateral to the cortical lesion. These results suggest that orientation to discrete visual targets is mediated by both tectal and geniculostriate pathways with the tectofugal system subserving responses to stimuli throughout the entire visual field and the corticofugal system organizing behavior to stimuli within the central portion of the visual field. It is argued that the output from these two parallel sensorimotor systems converges on common motor centers in the pontine reticular formation. [ABSTRACT FROM AUTHOR]

Significant progress has been made recently in research on lepidopterous sex pheromones. Advances in understanding the biochemical, neurobiological, and behavioral events that results in both successful and unsuccessful pheromone communication have allowed researchers to gain new insights into the genetic control and evolution of phermone systems. [ABSTRACT FROM AUTHOR]

The afferent and efferent connections of the vibrissal area of the rat motor cortex (VMCx) were investigated by injecting Phaseolus vulgaris leucoagglutinin (PHA-L) or wheat germ agglutinin-horseradish peroxidase into the physiologically defined VMCx. The VMCx formed reciprocal connections with the primary and secondary somatosensory cortex, lateral and ventrolateral orbital cortex, retrosplenial cortex, and perirhinal cortex. These corticocortical afferents originated from cell bodies in layers II-III and V, and some afferents originated from cell bodies in layer VI of the primary sensory cortex. All of the VMCx efferents terminated in layers I and V or layers I-III and V. The VMCx also formed reciprocal connections with the ventrolateral, ventromedial and centrolateral nucleus, the lateral portion of the mediodorsal nucleus and the posterior complex of the thalamus. It projected bilaterally to the caudate putamen, primarily ipsilaterally to the superior colliculus, anterior pretectal nucleus, and pontine nucleus, and mainly contralaterally to the oral part of the spinotrigeminal nucleus and the reticular formation around the facial nerve nucleus. Finally, injections of PHA-L into the superior colliculus demonstrated that this structure projected contralaterally to the lateral part of the facial nerve nucleus. These data suggest that the VMCx plays a key role in sensorimotor integration, through its extensive interconnectivity with numerous brain structures, and may modulate orientation behaviors by relaying processed information to the superior colliculus. [ABSTRACT FROM AUTHOR]