A 2-yr field study was conducted to assess the effects of transgenic japonica rice(KMD1 and KMD2) with a synthetic cry1 Ab gene from Bacillus thuingiensis Berliner on population dynamics and seasonal average densiti...A 2-yr field study was conducted to assess the effects of transgenic japonica rice(KMD1 and KMD2) with a synthetic cry1 Ab gene from Bacillus thuingiensis Berliner on population dynamics and seasonal average densities of five thrips species including Stenchaetothrips biformis(Bagnall),Frankliniella intonsa(Trybom),F.tenuicornis(Uzel),Haplothrips aculeatus(Fabricius),Haplothrips tritici(Kurd) and their general predatory flower bug,Orius similis Zheng as compared to the parental control rice line using the white,blue and yellow sticky card traps.Population dynamics and seasonal average densities of these five thrips species and their general predatory flower bug were not significantly affected by rice type.Additionally,the white sticky card trap was suggested to be the most suitable for monitoring the population of these five thrips species and their general predator.These results show that our tested Bt rice lines do not interrupt the population of non-target thrips species and their general predatory flower bug in the field,and also cannot result in more occurrence of these thrips species in the rice ecosystem.展开更多
Distinction of predator's diet and prey choice preference is a hot topic of current investigations. Spider being generalist predator and cosmopoliter in nature acts as biological control agent in many agro-ecosystems...Distinction of predator's diet and prey choice preference is a hot topic of current investigations. Spider being generalist predator and cosmopoliter in nature acts as biological control agent in many agro-ecosystems. In the current study, predatory efficacy of five spiders (Pardosa birmanica, Cyclosa insulana, Thomisus projectus, Plexippus paykulli and Lycosa terrestris) inhabiting the cotton fieldevaluated in the laboratory conditions maintained at (27+2)℃ temperature, 65%-5% relative humidity and 12 : 12 h of light and dark photoperiod. Four key cotton pests' viz. Bemisiatabaci, Amrascaderastans Thripstabaci and Helicoverpa armigera were utilized in the choice and no-choice predatory studies. The findings of current investigation revealed that each predatory spider utilized at least one pest species. Predation rate was found higher in the no-choice predation because of unavailability of substitutes feeding source. The investigation also indicated each predatory spider killed more pests than consumed. The findings of this study support the predatory role of spiders in controlling the cotton major pests.展开更多
In this paper the nature of predatory pricing is analyzed with genetic algorithms. It is found that, even under the same payoff structure, the results of the coevolution of weak monopolists and entrants are sensitive ...In this paper the nature of predatory pricing is analyzed with genetic algorithms. It is found that, even under the same payoff structure, the results of the coevolution of weak monopolists and entrants are sensitive to the representationof the decisionmaking process. Two representations are studied in this paper. One is the actionbased representation and the other the strategybased representation. The former is to represent a naive mind and the latter is to capture a sophisticated mind. For the actionbased representation, the convergence results are easily obtained and predatory pricing is only temporary in all simulations. However, for the strategybased representation, predatory pricing is not a rare phenomenon and its appearance is cyclical but not regular. Therefore, the snowball effect of a little craziness observed in the experimental game theory wins its support from this representation. Furthermore, the nature of predatory pricing has something to do with the evolution of the sophisticated rather than the naive minds.展开更多
Pine wilt is a serious and fatal disease in pine forests. It is caused by the pine wood nematode, Bursaphelenchus xylophilus, transmitted by the Japanese saw beetle Monochamus alternatus. Control of this disease depen...Pine wilt is a serious and fatal disease in pine forests. It is caused by the pine wood nematode, Bursaphelenchus xylophilus, transmitted by the Japanese saw beetle Monochamus alternatus. Control of this disease depends on reducing its vector population. The public is demanding environmentally friendly control methods and biological control has become increasingly seen as an impor-tant, safe and effective approach. Through our investigations both in the field and by breeding in our laboratory, a new predator of M. alternatus, Tetrigus lewisi (Coleoptera: Elateridae), was found for the first time in China. Given our continuous observations, we are assured that the predatory behavior of the elater can be separated into four parts, i.e., foraging and sensing, killing, eating and excre-tion. They always took several hours to eat the preys that have been killed momentarily. We finally found that most of the elaters preferably attacked in the stomach and abdomen of the larva of M. alternatus.展开更多
Many species have been drastically affected by rapid urbanization.Harris' s hawks from their natural habitat of open spaces and a supply of rodents,lizards and other small prey have been forced to change their nat...Many species have been drastically affected by rapid urbanization.Harris' s hawks from their natural habitat of open spaces and a supply of rodents,lizards and other small prey have been forced to change their natural environment adapting to living in open spaces in sub-and periurban areas.Specific areas include playgrounds,parks and school courtyards.The migration of this predatory species into these areas poses a risk to individuals,and especially the children are often attacked by claws,talons and beaks intentionally or as collateral damage while attacking rodent prey.In addition,the diverse micro-organisms harbored in the beaks and talons can result in wound infections,presenting a challenge to clinical management.Here we would like to present a case of an 80-year-old man with cellulitis of bom hands after sustaining minor injuries from the talons of a Harris s hawk and review the management options.We would also like to draw attention to the matter that,even though previously a rarity,more cases of injuries caused by birds of prey may be seen in hospital settings.展开更多
This paper develops a game-theory model for predatory pricing via in-depth analyses of three case studies:Brooke Group Ltd.v.Brown&Williamson Tobacco Corp.,Matsushita Electric Industries Co.v.Zenith Radio Corporat...This paper develops a game-theory model for predatory pricing via in-depth analyses of three case studies:Brooke Group Ltd.v.Brown&Williamson Tobacco Corp.,Matsushita Electric Industries Co.v.Zenith Radio Corporation,and AKZO Chemie BV v.Commission of the European Communities.This model is based on subsequent action game theory models and rational economics behavior,offering a chronological outline of the“predation”stages.It presents the predator’s decisions,the prey’s potential responses,possible loops,and the two distinctive outcomes.The analysis of the model in context of the three case studies demonstrates its practicality in assessing real-life predatory pricing scenarios and players’strategies.It’s flexibility also allows applications in related fields.Overall,this paper offers a comprehensive framework that bridges the gap between law,economics,and game theory in the study of predatory pricing,informing future research in this area.展开更多
Piscicidal effects of several solvent extarcts(distilled water,50%ethanol,absolute ethanol and 80%methanol)of Terminalia arjuna leaves,barks and fruits were studied against a common fresh water predatory fish,Heteropn...Piscicidal effects of several solvent extarcts(distilled water,50%ethanol,absolute ethanol and 80%methanol)of Terminalia arjuna leaves,barks and fruits were studied against a common fresh water predatory fish,Heteropneustes fossilis under laboratory conditions in terms of Behavior and mortality of fishes after 24 h.Fishes exposed to plant extracts showed agitating movement with quick surfacing,loss of balance,mucus secretion,and finally died.The LC50 values of distilled water,50%ethanol,absolute ethanol and 80%methanol extracts were found to be 311.726,236.141,183.541,478.794 ppm for leaves,117.894,96.998,38.990,304.193 ppm for barks and 1400.033,949.209,555.201,875.158 ppm for fruits,respectively.Chi-square values were found to be insignificant at P<0.05 in almost all plant extracts,indicating that observed and expected mortalities did not vary significantly in relation to doses,except 80%methanol extract of barks and absolute ethanol extract of fruits.The F-values of treatments were significant at P<0.01,except 80%methanol extract of fruits,in which F-values were insignificant in all replicates at P>0.01.Based on LC50 values,order of piscicidal activity followed the pattern,bark>leaf>fruit extracts.Order of piscicidal activity for the extracts was like absolute ethanol>50%ethanol>distilled water>80%methanol for leaf and bark,while for fruit extracts,trend was like absolute ethanol>80%methanol>50%ethanol>distilled water.展开更多
The emergence of the internet has transformed all areas of society.This includes the universe of scientific publications,with several publishers now exclusively focusing on the electronic format and open access model ...The emergence of the internet has transformed all areas of society.This includes the universe of scientific publications,with several publishers now exclusively focusing on the electronic format and open access model while expanding to a megajournal scope.in this context,the pandemic of predatory open access journals(POAJs)and meetings are of grave concern to the academic and research community.This new shift within academia produces a variety of new victims;namely,the authors themselves.in turn,scientific knowledge is often discredited,with the public placing less trust in science.Now more than ever,performing research with integrity and selecting a journal in which to publish requires close attention and expertise.The“predatory movement”has developed increasingly sophisticated techniques for misleading people into believing what seem to be credible professional layouts and legitimate invitations.initiatives such as the Jeffrey Beall’s list,the Cabell’s Scholarly Analytics and Think.Check.Submit offer some guidance to uncover the“parasitic”intervention of predatory journals and meetings,but specific education in this field is sorely needed.This work aims to review the main characteristics of predatory journals and meetings and to analyze this topic in the context of forensic and legal medicine research.展开更多
Predatory lady beetles (Coccinellidae)contribute to biological control of agri- cultural pests,however,multiple species frequently compete for similar resources in the same environment.Numerous studies have examined e...Predatory lady beetles (Coccinellidae)contribute to biological control of agri- cultural pests,however,multiple species frequently compete for similar resources in the same environment.Numerous studies have examined ecological interactions among the native North American convergent lady beetle (Hippodamia convergens)and two intro- duced species,the seven-spotted lady beetle (Coccinella septempunctata)and the Asian lady beetle (Harmonia axyridis),in agricultural fields and described multiyear population dynamics.However,the evolutionary dynamics of these interacting species of predatory beetles are uncharacterized.We utilize publicly available multilocus genotype data from geographically disjunct populations of these three species to estimate demography across North American populations.Coalescent analyses reveal (1)a recent (4-5years)decline (>12 fold)in microsatellite effective population size ofH.convergens,while expanding (mutation scaled growth rate in 1/u generations =2910,SD =362)over evolutionary time scales,(2)a massive (>150 fold),and very recent,effective population size decline in Ha. axyridis,and (3)population size growth (mutation scaled growth rate =997,SD =60)over recent and evolutionary time scales in C.septempunctata.Although these estimates are based on genetic data with different mutation rates and patterns of inheritance (mitochondrial versus nuclear),these dynamic and differing population size histories are striking. Further studies of the interactions of these predatory lady beetles in the field are thus warranted to explore the consequences of population size change and biological control activities for evolutionary trajectories in North America.展开更多
Integrated pest management (IPM) is widely practiced in commercial oil palm agriculture. This management system is intended to minimize the number of attacks by pest insects such as bagworms on crops, as well as cur...Integrated pest management (IPM) is widely practiced in commercial oil palm agriculture. This management system is intended to minimize the number of attacks by pest insects such as bagworms on crops, as well as curb economic loss with less dependency on chemical pesticides. One practice in IPM is the use of biological control agents such as predatory insects. In this study, we assessed the response of predatory natural enemies to pest outbreak and water stress, and document the habitat associations of potential pest predators. The abundances of 2 predatory insect species, namely Sycanus dichotomus and Cosmolestes pictieeps (Hemiptera: Reduviidae), were compared bagworm outbreak sites and nonoutbreak sites within oil palm plantations. We also examined habitat characteristics that influence the abundances of both predatory species. We found that the abundance of C. picticeps was significantly higher in bagworm outbreak sites than in nonoutbreak sites. There were no significant differences in the abundance ofS. dichotomus among outbreak and non-outbreak sites. Both species responded negatively to water stress in oil palm plantations. Concerning the relationship between predatory insect abundance and in situ habitat quality characteristics, our models explained 46.36% of variation for C. picticeps and 23.17% of variation for S. dichotomus. Both species of predatory insects thrived from the planting of multiple beneficial plants in oil palm plantations. The results suggest that C. picticeps can be used as a biological agent to control bagworm populations in oil palm plantations, but S. dichotomus has no or little potential for such ecosystem service.展开更多
Predatory hunting is an important type of innate behavior evolutionarily conserved across the animal king-dom.It is typically composed of a set of sequential actions,including prey search,pursuit,attack,and consumptio...Predatory hunting is an important type of innate behavior evolutionarily conserved across the animal king-dom.It is typically composed of a set of sequential actions,including prey search,pursuit,attack,and consumption.This behavior is subject to control by the nervous system.Early studies used toads as a model to probe the neuroethology of hunting,which led to the proposal of a sensory-triggered release mechanism for hunting actions.More recent stud-ies have used genetically-trackable zebrafish and rodents and have made breakthrough discoveries in the neuroethol-ogy and neurocircuits underlying this behavior.Here,we review the sophisticated neurocircuitry involved in hunting and summarize the detailed mechanism for the circuitry to encode various aspects of hunting neuroethology,including sensory processing,sensorimotor transformation,motivation,and sequential encoding of hunting actions.We also discuss the overlapping brain circuits for hunting and feeding and point out the limitations of current studies.We propose that hunting is an ideal behavioral paradigm in which to study the neuroethology of motivated behaviors,which may shed new light on epidemic disorders,including bingeeating,obesity,and obsessive-compulsive disorders.展开更多
The two-spotted spider mite,Tetranychus urticae Koch,is one of the most harmful pests in many agroecosystems worldwide.To effectively manage this pest,there is an urgent need to develop novel bio-active acaricides tha...The two-spotted spider mite,Tetranychus urticae Koch,is one of the most harmful pests in many agroecosystems worldwide.To effectively manage this pest,there is an urgent need to develop novel bio-active acaricides that support integrated pest management strategies targeting T.urticae.In this study,we explored the acaricidal effects of xenocoumacin 1 (Xcn1) on T.urticae and its predator Neoseiulus californicus using the highly puri?ed compound.Xcn1 was extracted and purified from the cell-free supernatant of the Xenorhabdus nematophila CB6 mutant constructed by the easy promoter activated compound identi?cation (easyPACId) method.When the concentration of Xcn1 exceeded 100μg mL~(–1),the survival rate of spider mite adults declined to below 40%and the fecundity was decreased by 80%at six days post-application.At concentrations of 25 and 50μg mL~(–1),Xcn1 signi?cantly impeded spider mite development by inhibiting the molt.However,neither concentration had any adverse effects on the survival or reproduction of the predatory mite N.californicus.The results from laboratory and semi-?eld experiments consistently demonstrated the effectiveness of the antimicrobial metabolite Xcn1 in controlling pest mites at both the molecular and physiological levels.Our study offers a promising possibility that combines the compatible biocontrol agents of Xcn1 and predatory mites for integrated pest mite control.展开更多
[Objective] This study was conducted to explore the predation of Pardosa pseudoannulata and Pirata procurva_ on Plutela xylostela larvae. [Method] The quantities of P. xylostela larvae predated by the two spider speci...[Objective] This study was conducted to explore the predation of Pardosa pseudoannulata and Pirata procurva_ on Plutela xylostela larvae. [Method] The quantities of P. xylostela larvae predated by the two spider species at different temperatures and the quantities of P. xylostela larvae predated by P. pseudoannula-ta_in different volumes were analyzed. Based on three factors at five levels, the quadratic general regression rotation combination design was used to study the combined control effect of the two spider species on P. xylostela_larvae and the control effect of P. pseudoannulata on the larvae of P. xylostela and Spodoptera litura. [Result] The quantities of P. xylostela_ larvae predated by the two spider species increased first and then decreased with the increase of temperature, and the functional predation response of P. pseudoannulata and P. procurva_ on the fourth instar larvae of P. xylostela_fitted the Hol ing-Ⅱ model, and the Hol ing-Ⅲmodel could perfect the evaluation on the predation effect. Volume had great effect on the feeding of P. pseudoannulata. lnstantaneous attack ability (a’), the time to handle one prey (Th) and predation function (a’/Th) in a smal er volume were al higher than that in a larger volume. The predation of the two spider species on P. xylostela_larvae was positively correlated with their densities. The overal effect of the three factors was: the density of P. xylostela&gt;the density of P. procurva&gt;the density of P. pseudoannulata. The densities of P. xylostela and S. litura larvae could affect the feeding amount of P. pseudoannulata. But there was no predation preference for P. pseudoannulata on the larvae of P. xylostela and S. litura. [Con-clusion] The results wil provide a reference for the evaluation of control effect of_P. xylostela_by P. pseudoannulata_and P. procurva in the field.展开更多
Brain asymmetry for processing visual information is widespread in animals.However,it is still unknown how the complexity of the underlying neural network activities represents this asymmetrical pattern in the brain.I...Brain asymmetry for processing visual information is widespread in animals.However,it is still unknown how the complexity of the underlying neural network activities represents this asymmetrical pattern in the brain.In the present study,we investigated this complexity using the approximate entropy(ApEn)protocol for electroencephalogram(EEG)recordings from the forebrain and midbrain while the music frogs(Nidirana daunchina)attacked prey stimulus.The results showed that(1)more significant prey responses were evoked by the prey stimulus presented in the right visual field than that in the left visual field,consistent with the idea that right-eye preferences for predatory behaviors exist in animals including anurans;(2)in general,the ApEn value of the left hemisphere(especially the left mesencephalon)was greatest under various stimulus conditions,suggesting that visual lateralization could be reflected by the dynamics of underlying neural network activities and that the stable left-hemisphere dominance of EEG ApEn may play an important role in maintaining this brain asymmetry.展开更多
Phytoseiulus persimilis is an important biological control agent, commercially produced worldwide. To increase understandings of its reproduction, herein we provided quantitative descriptions of the inflation and defl...Phytoseiulus persimilis is an important biological control agent, commercially produced worldwide. To increase understandings of its reproduction, herein we provided quantitative descriptions of the inflation and deflation of its spermathecae as a function of time and copulation duration, and the quantitative impact of copulation termination on volume of spermatheca vesicle, fecundity, and offspring sex ratio. After mating started, at least one spermatheca started to inflate immediately, but no egg was produced until spermatheca volume reached 1 021 μm3. Beyond this size, cumulative fecundity was linearly correlated with vesicle volume. Producing one egg required 36 μm3 volume increase of the vesicle. Each spermatheca vesicle reached its peak size at the end of mating duration(ca. 2.38 h after mating started), and started to shrink immediately. In 24 h, ca. 71% individuals had one completely shriveled spermatheca, while in 72 h all individuals had at least one shriveled spermatheca. The estimated maximum cumulative fecundity per female after a single mating is(69.4±7.7) eggs. No significant impact of mating termination on offspring sex ratio was observed after mating duration reached 60 min, while higher proportion of male offspring was observed when mating duration is 15 or 30 min. This study is the first step to investigate possible male impact on offspring sex ratio in P. persimilis. Our results suggested the number of sperms received during mating be a restriction factor of P. persimilis offspring sex ratio regulation.展开更多
In the view of the disadvantages of complex method (CM) and electromagnetism-like algorithm (EM), complex electromagnetism-like hybrid algorithm (CEM) was proposed by embedding complex method into electromagnetism-lik...In the view of the disadvantages of complex method (CM) and electromagnetism-like algorithm (EM), complex electromagnetism-like hybrid algorithm (CEM) was proposed by embedding complex method into electromagnetism-like algorithm as local optimization algorithm. CEM was adopted to search the minimum safety factor in slope stability analysis and the results show that CEM holds advantages over EM and CM. It combines the merits of two and is more stable and efficient. For further improvement, two CEM hybrid algorithms based on predatory search (PS) strategies were proposed, both of which consist of modified algorithms and the search area of which is dynamically adjusted by changing restriction. The CEM-PS1 adopts theoretical framework of original predatory search strategy. The CEM-PS2 employs the idea of area-restricted search learned from predatory search strategy, but the algorithm structure is simpler. Both the CEM-PS1 and CEM-PS2 have been demonstrated more effective and efficient than the others. As for complex method which locates in hybrid algorithm, the optimization can be achieved at a convergence precision of 1×10-3, which is recommended to use.展开更多
The predatory mite, Phytoseius plumifer (Canestrini & Fanzago), is one of the most abundant natural enemies and efficient predator of phytophagous mites in Iran. The miticides hexythiazox (Nisorun, EC 10%), fenpy...The predatory mite, Phytoseius plumifer (Canestrini & Fanzago), is one of the most abundant natural enemies and efficient predator of phytophagous mites in Iran. The miticides hexythiazox (Nisorun, EC 10%), fenpyroximate (Ortus, SC 5%), and abamectin (Vertimec, EC 1.8%) were tested in the laboratory for their side effects on P. plumifer. The miticides were applied at the highest field recommended concentration (N) to detached leaves using a Potter Tower to deposit 2 mg spray solution per cm2. Percent predator mortality was evaluated from the protonymph up to the adult stage including the first five days of the oviposition period. Analysis of data showed that the total effect values of hexythiazox were below the lower threshold, and thus it could be considered to be a harmless miticide to P. plumifer. In contrast, the total effects of fenpyroximate and abamectin were found harmful to the predatory mite at the highest field recommended concentrations.展开更多
Western flower thrips, Frankliniella occidentalis, is a major cosmopolitan insect pest causing direct and indirect damage to greenhouse-grown horticultural crops. The primary way of managing western flower thrips popu...Western flower thrips, Frankliniella occidentalis, is a major cosmopolitan insect pest causing direct and indirect damage to greenhouse-grown horticultural crops. The primary way of managing western flower thrips populations is by routinely applying insecticides, which target the aboveground life stages: larvae and adult. However, insecticides are minimally effective against the pupal stages (prepupae and pupae) that reside in the growing medium or soil. Therefore, soil-dwelling biological control agents including: predatory mites [Stratiolaelaps scimitus and Hypoaspis = (Geolaelaps) aculeifer], and a rove beetle, Dalotia coriaria may be a viable option to induce mortality on the pupal stages. These predators will feed on the pupal stages of the western flower thrips and can provide mortality on a life stage that is tolerant of insecticide applications. However, these biological control agents need to be used in conjunction with other plant protection strategies, such as insecticides and/or biological control agents that target the aboveground life stages (larvae and adult) to effectively manage western flower thrips populations in greenhouse production systems.展开更多
Purpose:This article explores the implications of publication requirements for the research output of Ukrainian academics in Scopus in 1999-2019.As such it contributes to the existing body of knowledge on quantitative...Purpose:This article explores the implications of publication requirements for the research output of Ukrainian academics in Scopus in 1999-2019.As such it contributes to the existing body of knowledge on quantitative and qualitative effects of research evaluation policies.Design/methodology/approach:Three metrics were chosen to analyse the implications of publication requirements for the quality of research output:publications in predatory journals,publications in local journals and publications per SNIP quartile from the disciplinary perspective.Findings:Study results highlight,that,firstly,publications of Ukrainian authors in predatory journals rose to 1%in 2019.Secondly,the share of publications in local journals reached the peak of 47.3%in 2015.In 2019 it fell to 31.8%.Thirdly,though the total number of publications has risen dramatically since 2011,but the share of Q3+Q4 has exceeded the share of Q1+Q2.To summarise,the study findings highligh,that research evaluation policies are required to contain not only quantitative but also qualitative criteria.Research limitation:The study does not explore in detail the effects of a particular type of publication requirements.Practical implications:The findings of the study have practical implications for policymakers and university managers aimed to develop research evaluation policies.Originality/value:This paper gains insights into the effects of publication requirements on the research output of Ukrainian academics in Scopus.展开更多
基金Financial supports were provided from the Special Research Projects for Developing Transgenic Plants,China(2013ZX08011-001)the China National Science Fund for Innovative Research Groups of Biological Control(31021003)the National 973 Program of China(2007CB109202)
文摘A 2-yr field study was conducted to assess the effects of transgenic japonica rice(KMD1 and KMD2) with a synthetic cry1 Ab gene from Bacillus thuingiensis Berliner on population dynamics and seasonal average densities of five thrips species including Stenchaetothrips biformis(Bagnall),Frankliniella intonsa(Trybom),F.tenuicornis(Uzel),Haplothrips aculeatus(Fabricius),Haplothrips tritici(Kurd) and their general predatory flower bug,Orius similis Zheng as compared to the parental control rice line using the white,blue and yellow sticky card traps.Population dynamics and seasonal average densities of these five thrips species and their general predatory flower bug were not significantly affected by rice type.Additionally,the white sticky card trap was suggested to be the most suitable for monitoring the population of these five thrips species and their general predator.These results show that our tested Bt rice lines do not interrupt the population of non-target thrips species and their general predatory flower bug in the field,and also cannot result in more occurrence of these thrips species in the rice ecosystem.
文摘Distinction of predator's diet and prey choice preference is a hot topic of current investigations. Spider being generalist predator and cosmopoliter in nature acts as biological control agent in many agro-ecosystems. In the current study, predatory efficacy of five spiders (Pardosa birmanica, Cyclosa insulana, Thomisus projectus, Plexippus paykulli and Lycosa terrestris) inhabiting the cotton fieldevaluated in the laboratory conditions maintained at (27+2)℃ temperature, 65%-5% relative humidity and 12 : 12 h of light and dark photoperiod. Four key cotton pests' viz. Bemisiatabaci, Amrascaderastans Thripstabaci and Helicoverpa armigera were utilized in the choice and no-choice predatory studies. The findings of current investigation revealed that each predatory spider utilized at least one pest species. Predation rate was found higher in the no-choice predation because of unavailability of substitutes feeding source. The investigation also indicated each predatory spider killed more pests than consumed. The findings of this study support the predatory role of spiders in controlling the cotton major pests.
文摘In this paper the nature of predatory pricing is analyzed with genetic algorithms. It is found that, even under the same payoff structure, the results of the coevolution of weak monopolists and entrants are sensitive to the representationof the decisionmaking process. Two representations are studied in this paper. One is the actionbased representation and the other the strategybased representation. The former is to represent a naive mind and the latter is to capture a sophisticated mind. For the actionbased representation, the convergence results are easily obtained and predatory pricing is only temporary in all simulations. However, for the strategybased representation, predatory pricing is not a rare phenomenon and its appearance is cyclical but not regular. Therefore, the snowball effect of a little craziness observed in the experimental game theory wins its support from this representation. Furthermore, the nature of predatory pricing has something to do with the evolution of the sophisticated rather than the naive minds.
文摘Pine wilt is a serious and fatal disease in pine forests. It is caused by the pine wood nematode, Bursaphelenchus xylophilus, transmitted by the Japanese saw beetle Monochamus alternatus. Control of this disease depends on reducing its vector population. The public is demanding environmentally friendly control methods and biological control has become increasingly seen as an impor-tant, safe and effective approach. Through our investigations both in the field and by breeding in our laboratory, a new predator of M. alternatus, Tetrigus lewisi (Coleoptera: Elateridae), was found for the first time in China. Given our continuous observations, we are assured that the predatory behavior of the elater can be separated into four parts, i.e., foraging and sensing, killing, eating and excre-tion. They always took several hours to eat the preys that have been killed momentarily. We finally found that most of the elaters preferably attacked in the stomach and abdomen of the larva of M. alternatus.
文摘Many species have been drastically affected by rapid urbanization.Harris' s hawks from their natural habitat of open spaces and a supply of rodents,lizards and other small prey have been forced to change their natural environment adapting to living in open spaces in sub-and periurban areas.Specific areas include playgrounds,parks and school courtyards.The migration of this predatory species into these areas poses a risk to individuals,and especially the children are often attacked by claws,talons and beaks intentionally or as collateral damage while attacking rodent prey.In addition,the diverse micro-organisms harbored in the beaks and talons can result in wound infections,presenting a challenge to clinical management.Here we would like to present a case of an 80-year-old man with cellulitis of bom hands after sustaining minor injuries from the talons of a Harris s hawk and review the management options.We would also like to draw attention to the matter that,even though previously a rarity,more cases of injuries caused by birds of prey may be seen in hospital settings.
文摘This paper develops a game-theory model for predatory pricing via in-depth analyses of three case studies:Brooke Group Ltd.v.Brown&Williamson Tobacco Corp.,Matsushita Electric Industries Co.v.Zenith Radio Corporation,and AKZO Chemie BV v.Commission of the European Communities.This model is based on subsequent action game theory models and rational economics behavior,offering a chronological outline of the“predation”stages.It presents the predator’s decisions,the prey’s potential responses,possible loops,and the two distinctive outcomes.The analysis of the model in context of the three case studies demonstrates its practicality in assessing real-life predatory pricing scenarios and players’strategies.It’s flexibility also allows applications in related fields.Overall,this paper offers a comprehensive framework that bridges the gap between law,economics,and game theory in the study of predatory pricing,informing future research in this area.
基金We acknowledge funding supports of the National Key R&D Program of China(Grant No.2017YFC1600806)National Natural Science Foundation of China(Grant Nos.31972042,31950410550 and 31571806)+1 种基金China Postdoctoral Science Foundation(Grant Nos.2019T120402 and 2017M621657)High-level talents project of Six Talent Peaks in Jiangsu Province of China(Grant No.SWYY-018).
文摘Piscicidal effects of several solvent extarcts(distilled water,50%ethanol,absolute ethanol and 80%methanol)of Terminalia arjuna leaves,barks and fruits were studied against a common fresh water predatory fish,Heteropneustes fossilis under laboratory conditions in terms of Behavior and mortality of fishes after 24 h.Fishes exposed to plant extracts showed agitating movement with quick surfacing,loss of balance,mucus secretion,and finally died.The LC50 values of distilled water,50%ethanol,absolute ethanol and 80%methanol extracts were found to be 311.726,236.141,183.541,478.794 ppm for leaves,117.894,96.998,38.990,304.193 ppm for barks and 1400.033,949.209,555.201,875.158 ppm for fruits,respectively.Chi-square values were found to be insignificant at P<0.05 in almost all plant extracts,indicating that observed and expected mortalities did not vary significantly in relation to doses,except 80%methanol extract of barks and absolute ethanol extract of fruits.The F-values of treatments were significant at P<0.01,except 80%methanol extract of fruits,in which F-values were insignificant in all replicates at P>0.01.Based on LC50 values,order of piscicidal activity followed the pattern,bark>leaf>fruit extracts.Order of piscicidal activity for the extracts was like absolute ethanol>50%ethanol>distilled water>80%methanol for leaf and bark,while for fruit extracts,trend was like absolute ethanol>80%methanol>50%ethanol>distilled water.
文摘The emergence of the internet has transformed all areas of society.This includes the universe of scientific publications,with several publishers now exclusively focusing on the electronic format and open access model while expanding to a megajournal scope.in this context,the pandemic of predatory open access journals(POAJs)and meetings are of grave concern to the academic and research community.This new shift within academia produces a variety of new victims;namely,the authors themselves.in turn,scientific knowledge is often discredited,with the public placing less trust in science.Now more than ever,performing research with integrity and selecting a journal in which to publish requires close attention and expertise.The“predatory movement”has developed increasingly sophisticated techniques for misleading people into believing what seem to be credible professional layouts and legitimate invitations.initiatives such as the Jeffrey Beall’s list,the Cabell’s Scholarly Analytics and Think.Check.Submit offer some guidance to uncover the“parasitic”intervention of predatory journals and meetings,but specific education in this field is sorely needed.This work aims to review the main characteristics of predatory journals and meetings and to analyze this topic in the context of forensic and legal medicine research.
文摘Predatory lady beetles (Coccinellidae)contribute to biological control of agri- cultural pests,however,multiple species frequently compete for similar resources in the same environment.Numerous studies have examined ecological interactions among the native North American convergent lady beetle (Hippodamia convergens)and two intro- duced species,the seven-spotted lady beetle (Coccinella septempunctata)and the Asian lady beetle (Harmonia axyridis),in agricultural fields and described multiyear population dynamics.However,the evolutionary dynamics of these interacting species of predatory beetles are uncharacterized.We utilize publicly available multilocus genotype data from geographically disjunct populations of these three species to estimate demography across North American populations.Coalescent analyses reveal (1)a recent (4-5years)decline (>12 fold)in microsatellite effective population size ofH.convergens,while expanding (mutation scaled growth rate in 1/u generations =2910,SD =362)over evolutionary time scales,(2)a massive (>150 fold),and very recent,effective population size decline in Ha. axyridis,and (3)population size growth (mutation scaled growth rate =997,SD =60)over recent and evolutionary time scales in C.septempunctata.Although these estimates are based on genetic data with different mutation rates and patterns of inheritance (mitochondrial versus nuclear),these dynamic and differing population size histories are striking. Further studies of the interactions of these predatory lady beetles in the field are thus warranted to explore the consequences of population size change and biological control activities for evolutionary trajectories in North America.
文摘Integrated pest management (IPM) is widely practiced in commercial oil palm agriculture. This management system is intended to minimize the number of attacks by pest insects such as bagworms on crops, as well as curb economic loss with less dependency on chemical pesticides. One practice in IPM is the use of biological control agents such as predatory insects. In this study, we assessed the response of predatory natural enemies to pest outbreak and water stress, and document the habitat associations of potential pest predators. The abundances of 2 predatory insect species, namely Sycanus dichotomus and Cosmolestes pictieeps (Hemiptera: Reduviidae), were compared bagworm outbreak sites and nonoutbreak sites within oil palm plantations. We also examined habitat characteristics that influence the abundances of both predatory species. We found that the abundance of C. picticeps was significantly higher in bagworm outbreak sites than in nonoutbreak sites. There were no significant differences in the abundance ofS. dichotomus among outbreak and non-outbreak sites. Both species responded negatively to water stress in oil palm plantations. Concerning the relationship between predatory insect abundance and in situ habitat quality characteristics, our models explained 46.36% of variation for C. picticeps and 23.17% of variation for S. dichotomus. Both species of predatory insects thrived from the planting of multiple beneficial plants in oil palm plantations. The results suggest that C. picticeps can be used as a biological agent to control bagworm populations in oil palm plantations, but S. dichotomus has no or little potential for such ecosystem service.
文摘Predatory hunting is an important type of innate behavior evolutionarily conserved across the animal king-dom.It is typically composed of a set of sequential actions,including prey search,pursuit,attack,and consumption.This behavior is subject to control by the nervous system.Early studies used toads as a model to probe the neuroethology of hunting,which led to the proposal of a sensory-triggered release mechanism for hunting actions.More recent stud-ies have used genetically-trackable zebrafish and rodents and have made breakthrough discoveries in the neuroethol-ogy and neurocircuits underlying this behavior.Here,we review the sophisticated neurocircuitry involved in hunting and summarize the detailed mechanism for the circuitry to encode various aspects of hunting neuroethology,including sensory processing,sensorimotor transformation,motivation,and sequential encoding of hunting actions.We also discuss the overlapping brain circuits for hunting and feeding and point out the limitations of current studies.We propose that hunting is an ideal behavioral paradigm in which to study the neuroethology of motivated behaviors,which may shed new light on epidemic disorders,including bingeeating,obesity,and obsessive-compulsive disorders.
基金supported by the National Natural Science Foundation of China(32070402)the Beijing Natural Science Foundation,China(6222052)。
文摘The two-spotted spider mite,Tetranychus urticae Koch,is one of the most harmful pests in many agroecosystems worldwide.To effectively manage this pest,there is an urgent need to develop novel bio-active acaricides that support integrated pest management strategies targeting T.urticae.In this study,we explored the acaricidal effects of xenocoumacin 1 (Xcn1) on T.urticae and its predator Neoseiulus californicus using the highly puri?ed compound.Xcn1 was extracted and purified from the cell-free supernatant of the Xenorhabdus nematophila CB6 mutant constructed by the easy promoter activated compound identi?cation (easyPACId) method.When the concentration of Xcn1 exceeded 100μg mL~(–1),the survival rate of spider mite adults declined to below 40%and the fecundity was decreased by 80%at six days post-application.At concentrations of 25 and 50μg mL~(–1),Xcn1 signi?cantly impeded spider mite development by inhibiting the molt.However,neither concentration had any adverse effects on the survival or reproduction of the predatory mite N.californicus.The results from laboratory and semi-?eld experiments consistently demonstrated the effectiveness of the antimicrobial metabolite Xcn1 in controlling pest mites at both the molecular and physiological levels.Our study offers a promising possibility that combines the compatible biocontrol agents of Xcn1 and predatory mites for integrated pest mite control.
基金Supported by the Science and Technology Innovation Program of Chinese Academy of Agricultural Sciences(ASTIP-IBFC09)Technical System of Vegetable Industry of Hunan Province+1 种基金National Natural Science Foundation of China(31501653)Earmarked fund for Modern Agro-industry Technology Research System of China(CARS-19-E09)~~
文摘[Objective] This study was conducted to explore the predation of Pardosa pseudoannulata and Pirata procurva_ on Plutela xylostela larvae. [Method] The quantities of P. xylostela larvae predated by the two spider species at different temperatures and the quantities of P. xylostela larvae predated by P. pseudoannula-ta_in different volumes were analyzed. Based on three factors at five levels, the quadratic general regression rotation combination design was used to study the combined control effect of the two spider species on P. xylostela_larvae and the control effect of P. pseudoannulata on the larvae of P. xylostela and Spodoptera litura. [Result] The quantities of P. xylostela_ larvae predated by the two spider species increased first and then decreased with the increase of temperature, and the functional predation response of P. pseudoannulata and P. procurva_ on the fourth instar larvae of P. xylostela_fitted the Hol ing-Ⅱ model, and the Hol ing-Ⅲmodel could perfect the evaluation on the predation effect. Volume had great effect on the feeding of P. pseudoannulata. lnstantaneous attack ability (a’), the time to handle one prey (Th) and predation function (a’/Th) in a smal er volume were al higher than that in a larger volume. The predation of the two spider species on P. xylostela_larvae was positively correlated with their densities. The overal effect of the three factors was: the density of P. xylostela&gt;the density of P. procurva&gt;the density of P. pseudoannulata. The densities of P. xylostela and S. litura larvae could affect the feeding amount of P. pseudoannulata. But there was no predation preference for P. pseudoannulata on the larvae of P. xylostela and S. litura. [Con-clusion] The results wil provide a reference for the evaluation of control effect of_P. xylostela_by P. pseudoannulata_and P. procurva in the field.
基金supported by the grants from the National Natural Science Foundation of China(No.31970422,No.31672305 and No.31372217 to Guangzhan Fang)the Key Research Project of Education Department of Sichuan Province(No.18ZA0321 to Yansu Liu)。
文摘Brain asymmetry for processing visual information is widespread in animals.However,it is still unknown how the complexity of the underlying neural network activities represents this asymmetrical pattern in the brain.In the present study,we investigated this complexity using the approximate entropy(ApEn)protocol for electroencephalogram(EEG)recordings from the forebrain and midbrain while the music frogs(Nidirana daunchina)attacked prey stimulus.The results showed that(1)more significant prey responses were evoked by the prey stimulus presented in the right visual field than that in the left visual field,consistent with the idea that right-eye preferences for predatory behaviors exist in animals including anurans;(2)in general,the ApEn value of the left hemisphere(especially the left mesencephalon)was greatest under various stimulus conditions,suggesting that visual lateralization could be reflected by the dynamics of underlying neural network activities and that the stable left-hemisphere dominance of EEG ApEn may play an important role in maintaining this brain asymmetry.
基金supported by the National Key R&D Program of China(2017YFD0200400)the National Natural Science Foundation of China(31701850)the Basal Research Fund of Chinese Academy of Agricultural Sciences(Y2016PT13)
文摘Phytoseiulus persimilis is an important biological control agent, commercially produced worldwide. To increase understandings of its reproduction, herein we provided quantitative descriptions of the inflation and deflation of its spermathecae as a function of time and copulation duration, and the quantitative impact of copulation termination on volume of spermatheca vesicle, fecundity, and offspring sex ratio. After mating started, at least one spermatheca started to inflate immediately, but no egg was produced until spermatheca volume reached 1 021 μm3. Beyond this size, cumulative fecundity was linearly correlated with vesicle volume. Producing one egg required 36 μm3 volume increase of the vesicle. Each spermatheca vesicle reached its peak size at the end of mating duration(ca. 2.38 h after mating started), and started to shrink immediately. In 24 h, ca. 71% individuals had one completely shriveled spermatheca, while in 72 h all individuals had at least one shriveled spermatheca. The estimated maximum cumulative fecundity per female after a single mating is(69.4±7.7) eggs. No significant impact of mating termination on offspring sex ratio was observed after mating duration reached 60 min, while higher proportion of male offspring was observed when mating duration is 15 or 30 min. This study is the first step to investigate possible male impact on offspring sex ratio in P. persimilis. Our results suggested the number of sperms received during mating be a restriction factor of P. persimilis offspring sex ratio regulation.
基金Project(10972238) supported by the National Natural Science Foundation of ChinaProject(2010ssxt237) supported by Graduate Student Innovation Foundation of Central South University, ChinaProject supported by Excellent Doctoral Thesis Support Program of Central South University, China
文摘In the view of the disadvantages of complex method (CM) and electromagnetism-like algorithm (EM), complex electromagnetism-like hybrid algorithm (CEM) was proposed by embedding complex method into electromagnetism-like algorithm as local optimization algorithm. CEM was adopted to search the minimum safety factor in slope stability analysis and the results show that CEM holds advantages over EM and CM. It combines the merits of two and is more stable and efficient. For further improvement, two CEM hybrid algorithms based on predatory search (PS) strategies were proposed, both of which consist of modified algorithms and the search area of which is dynamically adjusted by changing restriction. The CEM-PS1 adopts theoretical framework of original predatory search strategy. The CEM-PS2 employs the idea of area-restricted search learned from predatory search strategy, but the algorithm structure is simpler. Both the CEM-PS1 and CEM-PS2 have been demonstrated more effective and efficient than the others. As for complex method which locates in hybrid algorithm, the optimization can be achieved at a convergence precision of 1×10-3, which is recommended to use.
基金partly supported by Iran National Science Foundation (84-63)
文摘The predatory mite, Phytoseius plumifer (Canestrini & Fanzago), is one of the most abundant natural enemies and efficient predator of phytophagous mites in Iran. The miticides hexythiazox (Nisorun, EC 10%), fenpyroximate (Ortus, SC 5%), and abamectin (Vertimec, EC 1.8%) were tested in the laboratory for their side effects on P. plumifer. The miticides were applied at the highest field recommended concentration (N) to detached leaves using a Potter Tower to deposit 2 mg spray solution per cm2. Percent predator mortality was evaluated from the protonymph up to the adult stage including the first five days of the oviposition period. Analysis of data showed that the total effect values of hexythiazox were below the lower threshold, and thus it could be considered to be a harmless miticide to P. plumifer. In contrast, the total effects of fenpyroximate and abamectin were found harmful to the predatory mite at the highest field recommended concentrations.
文摘Western flower thrips, Frankliniella occidentalis, is a major cosmopolitan insect pest causing direct and indirect damage to greenhouse-grown horticultural crops. The primary way of managing western flower thrips populations is by routinely applying insecticides, which target the aboveground life stages: larvae and adult. However, insecticides are minimally effective against the pupal stages (prepupae and pupae) that reside in the growing medium or soil. Therefore, soil-dwelling biological control agents including: predatory mites [Stratiolaelaps scimitus and Hypoaspis = (Geolaelaps) aculeifer], and a rove beetle, Dalotia coriaria may be a viable option to induce mortality on the pupal stages. These predators will feed on the pupal stages of the western flower thrips and can provide mortality on a life stage that is tolerant of insecticide applications. However, these biological control agents need to be used in conjunction with other plant protection strategies, such as insecticides and/or biological control agents that target the aboveground life stages (larvae and adult) to effectively manage western flower thrips populations in greenhouse production systems.
文摘Purpose:This article explores the implications of publication requirements for the research output of Ukrainian academics in Scopus in 1999-2019.As such it contributes to the existing body of knowledge on quantitative and qualitative effects of research evaluation policies.Design/methodology/approach:Three metrics were chosen to analyse the implications of publication requirements for the quality of research output:publications in predatory journals,publications in local journals and publications per SNIP quartile from the disciplinary perspective.Findings:Study results highlight,that,firstly,publications of Ukrainian authors in predatory journals rose to 1%in 2019.Secondly,the share of publications in local journals reached the peak of 47.3%in 2015.In 2019 it fell to 31.8%.Thirdly,though the total number of publications has risen dramatically since 2011,but the share of Q3+Q4 has exceeded the share of Q1+Q2.To summarise,the study findings highligh,that research evaluation policies are required to contain not only quantitative but also qualitative criteria.Research limitation:The study does not explore in detail the effects of a particular type of publication requirements.Practical implications:The findings of the study have practical implications for policymakers and university managers aimed to develop research evaluation policies.Originality/value:This paper gains insights into the effects of publication requirements on the research output of Ukrainian academics in Scopus.