The Experts below are selected from a list of 321 Experts worldwide ranked by ideXlab platform
Roman Kuc - One of the best experts on this subject based on the ideXlab platform.
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Sensorimotor model of bat echolocation and Prey Capture.
The Journal of the Acoustical Society of America, 1994Co-Authors: Roman KucAbstract:A model of the bat sensorimotor system is developed using acoustics, signal processing, and control theory to illustrate the fundamental issues in accomplishing Prey Capture with echolocation. This model indicates that successful nonpredictive tracking of an ideal Prey can be accomplished with a very simple system. Circular apertures approximate the mouth and ears for deriving acoustic beam patterns, using the big brown bat Eptesicus fuscus as a model. Fundamental and overtone frequency components in the emissions allow two simultaneous acoustic beams to be defined. A pair of nonlinear, time‐variable, sampled‐data controllers alter the bat’s heading by applying yaw and pitch heading corrections. The yaw correction attempts to position the Prey in the midsagittal plane by nulling the interaural intensity difference of the fundamental component. The pitch correction compares the intensities of the overtone and fundamental components and acts to null their difference. By initiating pitch correction when the overtone intensity first exceeds that of the fundamental, the ambiguity problem is solved and the Prey is directed to the Capture region. Simulations of passive Prey Capture indicate that the Capture probability decreases as the Prey speed increases. Both quick and sluggish Prey are considered, with sluggish Prey found to be caught with slightly better efficiency. The magnitude of the Prey’s lateral motion just prior to Capture is observed to be an important factor determining Capture. The presence of a blind stage is considered, during which the interference of the emission with the echo is assumed to disrupt any sonar information. The presence of such a blind stage is found to have negligible effect on Capture efficiency.
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A Sonar-Based Mobile Robot Bat-Like Prey Capture
1992Co-Authors: Billur Barshan, Roman KucAbstract:This paper investigates the Prey Capture problem in an uncluttered environment for a mobile robot equipped with a wide-beam sonar system. An analytical lower bound for the mean Capture time is derived by assuming complete information about the Prey. Algorithms using qualitative and quantitative information are implemented for Prey Capture, and compared in terms of mean Capture time and Capture probability. Although qualitative information is sufficient, quantitative information assures more efficient Prey Capture to be achieved over a broader range of system parameters.
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ICRA - ROBAT: a sonar-based mobile robot for bat-like Prey Capture
Proceedings 1992 IEEE International Conference on Robotics and Automation, 1Co-Authors: Billur Barshan, Roman KucAbstract:The authors investigate the Prey Capture problem in an uncluttered environment for a mobile robot equipped with a wide-beam sonar system. An analytical lower bound for the mean Capture time is derived by assuming complete information about the Prey. Algorithms using qualitative and quantitative information are implemented for Prey Capture, and compared in terms of mean Capture time and Capture probability. Although qualitative information is sufficient, quantitative information assures more efficient Prey Capture to be achieved over a broader range of system parameters. Experimental results verifying the analysis and the simulations are provided. >
Diying Huang - One of the best experts on this subject based on the ideXlab platform.
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A specialized Prey-Capture apparatus in mid-Cretaceous rove beetles
Current biology : CB, 2019Co-Authors: Chenyang Cai, Dave J. Clarke, Zi-wei Yin, Diying HuangAbstract:Cai et al. report specialized Prey-Capture structures in two species of the stenine rove beetles from mid-Cretaceous Burmese amber. The discovery provides critical information about the origin and early evolution of both the novel predatory structure and of the subfamily Steninae (Coleoptera: Staphylinidae).
Judith S. Weis - One of the best experts on this subject based on the ideXlab platform.
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Evaluating Prey Capture by larval mummichogs (Fundulus heteroclitus) as a potential biomarker for contaminants.
Marine environmental research, 2003Co-Authors: Judith S. Weis, Jennifer Samson, Tong Zhou, Joan Skurnick, Peddrick WeisAbstract:Abstract We evaluated larval Prey Capture as a “behavioral biomarker” of contamination by examining feeding behavior of larval mummichogs ( Fundulus heteroclitus ) from many different sites, including a severely contaminated “Superfund” site, moderately contaminated sites, and reference areas. Prey Capture ability was related to sediment contaminant levels. The levels of contaminants at a site were highly correlated with each other, so that the impact of individual contaminants was confounded. The number of Captures of brine shrimp by mummichog larvae from all sites was highly variable, but significant negative correlations of Prey Capture were seen with mercury, lead, zinc, cadmium, and PCBs. As observed previously with adults, polyaromatic hydrocarbons (PAHs) did not appear to impair Prey Capture ability. The only site in which Prey Capture rates of 8-day old larvae were severely affected was the most highly contaminated Superfund site, Berry's Creek, NJ. This implies that larval Prey Capture is not as sensitive a behavioral biomarker for contamination as adult behavior studied previously.
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Prey Capture ability of mummichogs (Fundulus heteroclitus) as a behavioral biomarker for contaminants in estuarine systems
Canadian Journal of Fisheries and Aquatic Sciences, 2001Co-Authors: Judith S. Weis, Jennifer Samson, Tong Zhou, Joan Skurnick, Peddrick WeisAbstract:Prey Capture was evaluated as a behavioral biomarker of contamination by examining feeding behavior of adult mummichogs (Fundulus heteroclitus) from 13 sites. Prey Capture ability was related to sediment and tissue con - taminant levels and with previous genetic analyses. The levels of contaminants at a site were highly correlated with each other, confounding the impacts of individual contaminants. The number of Prey (grass shrimp) Captured was high- est in three of the cleanest sites. Sites with the lowest Capture rates were generally more contaminated. The number of Captures at all sites was highly variable, with both high and low efficiencies in highly contaminated populations. A sig - nificant relationship exists between the Mdh-A(a) allele and Captures, with higher Captures in the southern populations. Gut content analysis of field-collected fish had grass shrimp as the largest proportion of the diet at sites whose fish had the highest laboratory Capture rates. Thus, Prey Capture as a behavioral biomarker is ecologically relevant and corre - sponds to diet in the field. However, it is not especially sensitive due to great variability at each site. Behavioral differ - ences related to overall contaminant levels rather than to specific toxicants.
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Effects of methylmercury on ontogeny of Prey Capture ability and growth in three populations of larval Fundulus heteroclitus.
Archives of environmental contamination and toxicology, 2001Co-Authors: T. Zhou, R. Scali, Judith S. WeisAbstract:We used three populations of mummichogs (Fundulus heteroclitus), one from a polluted site (Piles Creek [PC], New Jersey) and two from cleaner sites (Tuckerton [TK], New Jersey, and East Hampton [EH], New York), to study (1) whether embryonic, embryonic plus larval, or larval exposure to methylmercury (MeHg) altered larval Prey Capture ability and growth; and (2) whether there were differences in tolerance to MeHg-induced behavioral changes among the three populations. Eggs and sperm were obtained from mummichogs Captured in the field, and their embryos and larvae were kept in clean sea water or MeHg solution (5, 10 μg/L). Larvae were then tested regularly for Prey Capture rates and Prey Capture efficiencies, and their lengths were measured. Embryonic exposure to MeHg induced transitory and recoverable impairments in larval Prey Capture ability, whereas larval exposure alone was relatively ineffective. When both embryos and larvae were treated, larval Prey Capture ability was affected at a lower concentration and a wider range of larval ages. In terms of growth and Prey Capture ability, response of larvae to embryonic or larval or exposure to both stages to MeHg varied with populations. TK fish were the most tolerant with respect to behavioral changes but were the most sensitive to MeHg in reduction of growth. EH fish were the most sensitive whenever embryos were treated, and PC fish were the most vulnerable after larval exposure. The population differences in response to MeHg intoxication may be due to pollution related factors or differences in behavioral-related genetic factors.
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Effects of embryonic exposure to methylmercury on larval Prey-Capture ability in the mummichog, fundulus heteroclitus
Environmental Toxicology and Chemistry, 1995Co-Authors: Judith S. Weis, Peddrick WeisAbstract:Embryos of the mummichog (Fundulus heteroclitus) were exposed to 2, 5, or 10 mg/L methylmercury (meHg) throughout development; these are concentrations below those which cause teratological effects in this species. After hatching, larvae were maintained in clean seawater and tested for Prey-Capture ability, using Artemia salina nauplii. Larvae that had been exposed to 10 mg/L methylmercury (and in two out of three trials, 5 mg/L) initially exhibited slower Prey-Capture ability than did the other groups. This is an indication of a subtle functional impairment due to the toxicant (“behavioral teratology”). However, the effect was transitory, and by about 1 week after hatching the Prey Capture of these larvae equalled that of the controls and the other treated groups. Growth of these larvae was also comparable to that of controls. The exposure may have caused retardation of neurological development, which was subsequently compensated for, and therefore no long-lasting effects were produced. In the field, however, embryos exposed to toxicants would probably continue to be exposed as larvae, and might not have the opportunity to recover from the deleterious effects, but rather might have them augmented.
Ondřej Novák - One of the best experts on this subject based on the ideXlab platform.
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Triggering a false alarm: wounding mimics Prey Capture in the carnivorous Venus flytrap (Dionaea muscipula).
The New phytologist, 2017Co-Authors: Andrej Pavlovič, Jana Jakšová, Ondřej NovákAbstract:In the carnivorous plant Venus flytrap (Dionaea muscipula), the sequence of events after Prey Capture resembles the well-known plant defence signalling pathway in response to pathogen or herbivore attack. Here, we used wounding to mimic Prey Capture to show the similarities and differences between botanical carnivory and plant defence mechanisms. We monitored movement, electrical signalling, jasmonate accumulation and digestive enzyme secretion in local and distal (systemic) traps in response to Prey Capture, the mechanical stimulation of trigger hairs and wounding. The Venus flytrap cannot discriminate between wounding and mechanical trigger hair stimulation. Both induced the same action potentials, rapid trap closure, hermetic trap sealing, the accumulation of jasmonic acid (JA) and its isoleucine conjugate (JA-Ile), and the secretion of proteases (aspartic and cysteine proteases), phosphatases and type I chitinase. The jasmonate accumulation and enzyme secretion were confined to the local traps, to which the stimulus was applied, which correlates with the propagation of electrical signals and the absence of a systemic response in the Venus flytrap. In contrast to plant defence mechanisms, the absence of a systemic response in carnivorous plant may represent a resource-saving strategy. During Prey Capture, it could be quite expensive to produce digestive enzymes in the traps on the plant without Prey.
Billur Barshan - One of the best experts on this subject based on the ideXlab platform.
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A Sonar-Based Mobile Robot Bat-Like Prey Capture
1992Co-Authors: Billur Barshan, Roman KucAbstract:This paper investigates the Prey Capture problem in an uncluttered environment for a mobile robot equipped with a wide-beam sonar system. An analytical lower bound for the mean Capture time is derived by assuming complete information about the Prey. Algorithms using qualitative and quantitative information are implemented for Prey Capture, and compared in terms of mean Capture time and Capture probability. Although qualitative information is sufficient, quantitative information assures more efficient Prey Capture to be achieved over a broader range of system parameters.
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ICRA - ROBAT: a sonar-based mobile robot for bat-like Prey Capture
Proceedings 1992 IEEE International Conference on Robotics and Automation, 1Co-Authors: Billur Barshan, Roman KucAbstract:The authors investigate the Prey Capture problem in an uncluttered environment for a mobile robot equipped with a wide-beam sonar system. An analytical lower bound for the mean Capture time is derived by assuming complete information about the Prey. Algorithms using qualitative and quantitative information are implemented for Prey Capture, and compared in terms of mean Capture time and Capture probability. Although qualitative information is sufficient, quantitative information assures more efficient Prey Capture to be achieved over a broader range of system parameters. Experimental results verifying the analysis and the simulations are provided. >
