This study examines the optimal pricing and production strategy of a closed-loop supply chain consisting of a manufacturer, a recycler, and consumers. Considering the cannibalization and promotion effects of remanufac...This study examines the optimal pricing and production strategy of a closed-loop supply chain consisting of a manufacturer, a recycler, and consumers. Considering the cannibalization and promotion effects of remanufactured products on new and secondhand products, we constructed Stackelberg game models under different scenarios. We analyze the impact of the changes in the two effects on the optimal prices and production strategies of the manufacturer and recycler, as well as their countermeasures. We find that (i) how the cannibalization and promotional effects influence the manufacturer and the recycler's pricing and production strategies differ under different scenarios;(ii) when the two effects exceed a threshold, the manufacturer abandons new or remanufactured products, and the recycler prefers to stop production on its new products or continue to remanufacture products;and (iii) the two effects always reduce the profits of the manufacturer and increase the profits of the recycler.展开更多
Ecdysis is a comm on phe nomenon that happe ns throughout the life phase of the giant freshwater prawn Macrobrachium rosenbergii.It is vital to better understand the correlation between cannibalism and biochemical com...Ecdysis is a comm on phe nomenon that happe ns throughout the life phase of the giant freshwater prawn Macrobrachium rosenbergii.It is vital to better understand the correlation between cannibalism and biochemical compound that exists during the moulting process.The objective of the present study was to determine the amino acid profile released by M.rosenbergii during the ecdysis process that promotes cannibalism.To accomplish this,changes in amino acid levels(total amino acid(TAA)and free amino acid(FAA))of tissue muscle,exoskeleton,and sample water of culture medium from the moulting(E-stage)and non-moulting(C-stage)prawns were analysed using highperformanee liquid chromatography(HPLC).Comparison study revealed that among the TAA compounds,proline and sarcosine of tissues from moulting prawn were found at the highest levels.The level of FAA from water that contains moulting prawns(E-stage)was dominated by tryptophan and proline.Significant values obtained in the present study suggested that these amino acid compounds act as a chemical cue to promote cannibalism in M.rosenbergii during ecdysis.The knowledge of compositions and compounds that were released during the moulting process should be helpful for better understanding of the mechanism and chemical cues that play roles on triggering cannibalism,and also for future dietary man ipulati on to improve feeding efficie ncies and feeding man agement,which in directly impacts productivity and profitability.展开更多
Although widely thought to be aggressive, solitary,and potentially cannibalistic, some spider species have evolved group-living behaviors. The distinct transition provides the framework to uncover groupliving evolutio...Although widely thought to be aggressive, solitary,and potentially cannibalistic, some spider species have evolved group-living behaviors. The distinct transition provides the framework to uncover groupliving evolution. Here, we conducted a comparative transcriptomic study and examined patterns of molecular evolution in two independently evolved group-living spiders and twelve solitary species. We report that positively selected genes among groupliving spider lineages are significantly enriched in nutrient metabolism and autophagy pathways. We also show that nutrient-related genes of group-living spiders convergently experience amino acid substitutions and accelerated relative evolutionary rates. These results indicate adaptive convergence of nutrient metabolism that may ensure energy supply in group-living spiders. The decelerated evolutionary rate of autophagy-related genes in group-living lineages is consistent with an increased constraint on energy homeostasis as would be required in a group-living environment. Together, the results show that energy metabolic pathways play an important role in the transition to group-living in spiders.展开更多
Wood frog Lithobates sylvaticus tadpoles develop in temporary wetlands where high population densities can force tadpoles into aggregations that intensify competition and can lead to cannibalism. However, chemical ala...Wood frog Lithobates sylvaticus tadpoles develop in temporary wetlands where high population densities can force tadpoles into aggregations that intensify competition and can lead to cannibalism. However, chemical alarm cues released from injured conspecifics could also dissuade cannibalism. The purpose of this study was to test mechanisms that may influence can- nibalistic behaviour. We tested whether the tendency of tadpoles to consume conspecifics would increase with the presence of competition and/or cues of profitable diets. Tadpoles placed in 1L experimental containers were tested for feeding initiation times of multiple diets, including conspecific tissues and conspecific tissues combined with chemical cues from the alternative diets （brine shrimp and comrneal）. Tadpoles were tested in the presence and absence of a competitor, and at multiple times over the course of the study. Tadpoles exhibited an altered response to diets over time; however the presence of a competitor reduced re- sponse times to all diets including conspecific tissues. Similarly, the presence of specific diets also reduced the response time of tadpoles to conspecific tissues. These results suggest competition among feeding tadpoles could result in aggressive behaviour leading to indiscriminate predation and cannibalism [Current Zoology 60 （5）： 571-580, 2014 ].展开更多
The present study examines the inherent flexibility in the feeding responses of S. infraimmaculata larvae to various breeding places. In addition, the study examines the hypothesis that in dry conditions, the water br...The present study examines the inherent flexibility in the feeding responses of S. infraimmaculata larvae to various breeding places. In addition, the study examines the hypothesis that in dry conditions, the water breeding places are the limiting factor for the survival and completion of the life cycle of populations of S. infraimmaculata. In the breeding sites, the food for larvae is not available, and cannibalism is the specific adaptation for larvae to grow and complete metamorphosis. S. infraimmaculata larvae feed on various invertebrates in different habitats, and cannibalism involves the adaptation to breeding places where food is not available. The growth only by cannibalism as the only way to adapt to these habitats because no food is found in breeding places at the southern border of its distribution is described here for the first time, not only in salamanders but in other animals as well.展开更多
Larval growth and survival of organisms are strongly influenced by abiotic and biotic factors, as demonstrated by ex- perimental studies performed under controlled laboratory or semi-natural conditions. Even if they h...Larval growth and survival of organisms are strongly influenced by abiotic and biotic factors, as demonstrated by ex- perimental studies performed under controlled laboratory or semi-natural conditions. Even if they have many advantages, ex- periments cannot cover the full complexity of natural conditions and field studies are needed for a better understanding of how environmental variation determines growth and development rate. Fire salamander Salamandra salamandra females give birth to larvae in a variety of habitats, both epigean and subterranean. In caves, salamander larvae successfully grow and metamorphose, but their growth is more than three times longer than in epigean streams and factors determining these differences require inves- tigation. We performed a field study to understand the factors related to the growth of fire salamander larvae in different envi- ronmental conditions, evaluating the relationship between environmental features and larval growth and differences between caves and epigean spring habitats. Both caves and epigean larvae successfully grew. Capture-mark-recapture allowed to individu- ally track individuals along their whole development, and measure their performance. Growth rate was significantly affected by environmental variables： larvae grew faster in environments with abundant invertebrates and few conspeciflcs. Taking into ac- count the effect of environmental variables, larval growth was significantly lower in caves. Food availability plays a different ef- fect in the two environments. Larval growth was positively related to the availability of invertebrates in epigean sites only. The development rate of hypogeous populations of salamanders is slower because of multiple parameters, but biotic factors play a much stronger role than the abiotic ones展开更多
Kin recognition has been widely observed in various taxa.Cannibalism avoidance may be a strong driver for the evolution of kin recognition,as it may avoid a reduction in inclusive fitness.Kin recognition has recently ...Kin recognition has been widely observed in various taxa.Cannibalism avoidance may be a strong driver for the evolution of kin recognition,as it may avoid a reduction in inclusive fitness.Kin recognition has recently been observed in a generalist phytoseiid,Amblyseius herbicolus(Acari:Phytoseiidae).This study experimentally examined the degree of relatedness needed between prey larvae and cannibal adults of A.herbicolus for the occurrence of kin discrimination.The adults were individually placed in enclosed arenas with two prey,a daughter and a more distant related larva,to observe their cannibalizing choice.The adults of A.herbicolus did not discriminate between close relatives(daughter versus niece)but preferably cannibalized more distant kin(i.e.,first and second cousins once removed).Phenotype matching and familiarization seem prominent as recognition mechanisms used by A.herbicolus adults.The effect of learning on kin recognition through prior contact in A.herbicolus requires further investigation.Studies on other adaptive functions of kin recognition of A.herbicolus,such as cooperation and parental care,may provide meaningful insights.展开更多
Sexual conflict is common in animals,and female sexual cannibalism represents an extreme form of sexual conflict.Males in many species have evolved a variety of strategies to circumvent or decrease the risk of female ...Sexual conflict is common in animals,and female sexual cannibalism represents an extreme form of sexual conflict.Males in many species have evolved a variety of strategies to circumvent or decrease the risk of female sexual cannibalism.Opportunistic mating,by which a male mates with a female when she is disturbed or when she is feeding or undertaking moulting,is one of such kinds of strategies,and widely occurs in many animals,especially in spiders.However,whether the occurrence of male opportunistic mating depends on the intensity of female sexual cannibalism remains largely unexplored.We predicted a positive correlation between them.In this study,we tested this prediction by performing a series of mating trials in the laboratory using 3 species of web-building spiders with different intensities of female sexual cannibalism:Nephila pilipes,Nephilengys malabarensis,and Parasteatoda tepidariorum.We found that the occurrence of male opportunistic mating was positively,though not statistically significantly,correlated with the intensity of female sexual cannibalism,thus supporting our hypothesis.All together,we provide evidence that male opportunistic mating may have evolved to respond to the selection pressure posed by female sexual cannibalism.展开更多
As one of the representative contemporary Asian American poets, Li-Young Lee in his two poetry collections entitled Rose and The Cify in Which 1Love You, recuperates his fragmented family history of immigration, and r...As one of the representative contemporary Asian American poets, Li-Young Lee in his two poetry collections entitled Rose and The Cify in Which 1Love You, recuperates his fragmented family history of immigration, and reconstructs a dynamic relationship with remembrance of the past that writes about him and defines his sense of self. This paper from the multicultural perspective argues that understanding the past through understanding his godlike father, Lee not only negotiates the formation of his subjectivity and identity, but also establishes a spiritual origin and belonging not merely with his ethnic communities but with all the immigrants as well. The paper finds that the strategy he employs in his articulation of his self is marked by his excellent execution of poetic epiphany, and metonymic cannibalism.展开更多
The launching of a new product is an essential strategy for the survival and success of a company. However, in certain cases, it can reduce the results obtained by other products of the same company. This fact is nam...The launching of a new product is an essential strategy for the survival and success of a company. However, in certain cases, it can reduce the results obtained by other products of the same company. This fact is named ＂cannibalism＂. Following by a review of the literature on cannibalism between goods, this paper outlines a conceptual approach, showing the way it happens, its impacts, and the possibility of its uses as a marketing tool. A new product should, wherever possible, be carefully designed to avoid cannibalizing old products, unless this process is carefully planned. Concludes that creating and launching of new products are critical to companies who want to stand out next to their markets and need to survive over time. A lot of new products launched each year, coupled with the fact that most are line extensions already worked by companies, so we assume that the occurrence of cannibalism is common, or that a significant amount of resources are designed to prevent or dilute it. There is a high probability of transfer of results obtained by established products to new products, since similarity between展开更多
Good brand name translation involves knowledge and expertise from many disciplines,such as linguistics,translation studies,marketing,aesthetics,psychology,law,etc.It is really an interdisciplinary practice that requir...Good brand name translation involves knowledge and expertise from many disciplines,such as linguistics,translation studies,marketing,aesthetics,psychology,law,etc.It is really an interdisciplinary practice that requires strenuous research and experience.In addition,the research methodology thereof is also quite problematic.This paper aims at bringing a latest translation theory—cannibalism into brand name translation and test its applicability in brand name translation practice.展开更多
At the end of the eighteenth century in Britain,due to the development of capitalism,money has become more and more important.Jane Austen describes in the Sense and Sensibility that under the influence of money,people...At the end of the eighteenth century in Britain,due to the development of capitalism,money has become more and more important.Jane Austen describes in the Sense and Sensibility that under the influence of money,people's values have become dis⁃torted,such as some have become family cannibalism,and some have become betrayers of love.At the same time,Austen also ex⁃presses her attitude towards money which gives us a lot of enlightenment.展开更多
In this paper, we consider the fear effect and gestation delay, and then establish a delayed predator-prey model with cannibalism. Firstly, we prove the well-posedness of the model. Secondly, the existence and stabili...In this paper, we consider the fear effect and gestation delay, and then establish a delayed predator-prey model with cannibalism. Firstly, we prove the well-posedness of the model. Secondly, the existence and stability of all equilibriums of the system are studied. Thirdly, the Hopf bifurcation at the coexistence equilibrium is investigated, and the conditions for the occurrence of Hopf bifurcation at the unique positive equilibrium point of the system with delay are determined. Finally, the numerical simulation results show that as the time delay increases, the equilibrium loses its stability, and the system has periodic solution.展开更多
Two populations of the kentrurostylid ciliate Pseudokeronopsis erythrina Chen et al.,2011 were isolated from a brackish wastewater treatment plant,Pisa,Italy and from a nutrient-rich freshwater body,the East Lake,Wuha...Two populations of the kentrurostylid ciliate Pseudokeronopsis erythrina Chen et al.,2011 were isolated from a brackish wastewater treatment plant,Pisa,Italy and from a nutrient-rich freshwater body,the East Lake,Wuhan,China.The populations were thoroughly investigated for their morphology,focusing on cell body plasticity.The study was supplemented with 18S rDNA phylogenetic analysis and mitogenome sequencing,following the integrative taxonomy approach.The Italian population possesses a great variation in terms of the frontal area,and the numbers of left marginal rows,and dorsal kineties.Additionally,the number of left marginal anlagen and dorsal kineties anlagen varied.For instance,additional small anlagen appeared in the left marginal rows,and two dorsal kineties anlagen derived from a single dorsal kinety.The Wuhan population resembled the type population(originally isolated from Guangzhou,China),differing only by the presence of an extra dorsal kinety.The existence of giant individuals characterized both new populations of P.erythrina although with some differences in their respective frequency and features.The 18S rDNA sequences of the Italian,Wuhan,and type populations were identical.Phylogenetic analyses showed that these three populations formed a distinct cluster within the clade containing P.songi,P.parasongi,and P.flava.The structure of the P.erythrina mitochondrial genome is also provided.The content of this genome closely resembled Pseudourostyla cristata,except for the absence of genes nadh3 and nadh6.Our findings suggest that the Wuhan population represents an intermediate form between the type and Italian populations.The greater morphological plasticity observed in the Italian population underscores the importance of molecular data and integrative analyses in species identification.展开更多
Maternal care is critically important for the survival of offspring in various animals.Spiders in the family Lycosidae are known for their hunting ability and maternal care behaviors.Predation on newly hatched spiderl...Maternal care is critically important for the survival of offspring in various animals.Spiders in the family Lycosidae are known for their hunting ability and maternal care behaviors.Predation on newly hatched spiderlings(pulli)by mother spiders decreases when they come into contact,and they carry the pulli on their dorsal surface.However,the factors inducing maternal care in lycosid spiders have not been elucidated.In this study,we investigated maternal care in Pardosa pseudoannulata(Araneae,Lycosidae)females.We proposed that the physical interaction between pulli and mother spiders induces maternal care via m-aminophenylacetylene(m-A),a novel regulator of maternal care.The presence of pulli on the dorsal abdomen of non-mother spiders suppressed pulli predation and in-creased the pulli-carrying rate,and the absence of pulli on the mother spiders increased pulli predation and decreased the pulli-carrying rate.The compound m-A was abundant in mother spiders,and it could be induced in non-mother spiders when they carried pulli.The topical application of m-A to non-mother spiders and m-A injection decreased pulli predation and increased the pulli-carrying rate,respectively;these findings indicate that m-A in both internal tissues and the integument is required for the induction of mater-nal care behavior,and the interaction between pulli and females induces the production of m-A.In-depth study of the regulatory mechanism of maternal care will enhance our understanding of spider biology and behavior.展开更多
With the rapid development of e-Commerce and takeaway platforms, retailers have gradually developed multi-channel operations. However, limited empirical studies explored the effects of an online channel offered by tak...With the rapid development of e-Commerce and takeaway platforms, retailers have gradually developed multi-channel operations. However, limited empirical studies explored the effects of an online channel offered by takeaway platforms on the store performance. Does an online channel addition have a synergy effect or a cannibalization effect on store performance? We empirically investigate these effects by analyzing a large dataset including diverse samples collected from multiple retailers across various regions. The dataset includes 2115 stores across 25 retailers for 10 months that includes two types of retail formats and covers 16 provinces and 21 cities of China. We study the impacts of the newly introduced online channel on the incumbent offline channel and the overall store performance.The empirical results reveal that the online channel addition mainly has a synergy effect. Specifically,for the overall store, it has a positive effect on the sales and product variety, whereas it has a negative effect on the basket size. Surprisingly, an online channel addition also has a positive effect on the offline sales. Our study adds novel values to multi-channel retailing literature by empirically researching the cannibalization and synergy effect of a new type of online channel, offered by takeaway platforms. It can provide insights for retail enterprises who are interested in introducing O2 O model.展开更多
In technology-intensive markets, it is a common strategy for companies to develop long-term multiple generation product lines instead of releasing consecutive single products. Even though this strategy is more profita...In technology-intensive markets, it is a common strategy for companies to develop long-term multiple generation product lines instead of releasing consecutive single products. Even though this strategy is more profitable than sequentially introducing single product generations, it can also result in inter-product line cannibalization. Cannibalization of multiple-generation product lines is a complex problem that needs to be taken into account at the early product line planning stage in order to sustain long-term profitability. In this paper, we propose an agent-based model that can simulate the potential cannibalization scenarios within a multiple-generation product line. We view a multiple-generation product line （MGPL） as complex adaptive system where each product generation in the MGPL adjusts its sales price over time based on the shifts in the market demand. The proposed model provides insights into how various pricing strategies impact the overall lifecycle profitability of MGPL and can be used to assist companies in developing appropriate dynamic pricing strategies at the early product line planning stages.展开更多
Cannibalism is an intriguing life history trait, that has been considered primarily in the predator, in predator-prey population models. Recent experimental evidence shows that prey cannibalism can have a significant ...Cannibalism is an intriguing life history trait, that has been considered primarily in the predator, in predator-prey population models. Recent experimental evidence shows that prey cannibalism can have a significant impact on predator-prey population dyna- mics in natural communities. Motivated by these experimental results, we investigate a ratio-dependent Holling-Tanner model, where cannibalism occurs simultaneously in both the predator and prey species. We show that depending on parameters, whilst prey or predator cannibalism acting alone leads to instability, their joint effect can actually stabilize the unstable interior equilibrium. Furthermore, in the spatially explicit model, we find that depending on parameters, prey and predator cannibalism acting jointly can cause spatial patterns to form, while not so acting individually. We discuss ecologicalconsequences of these findings in light of food chain dynamics, invasive species control and climate change.展开更多
Previous observations of cannibalism have been made in the aphid Acyrthosiphon pisum （L.）： this article seeks to quantify factors contributing to such be- haviors. We observed and quantified the responses of a numb...Previous observations of cannibalism have been made in the aphid Acyrthosiphon pisum （L.）： this article seeks to quantify factors contributing to such be- haviors. We observed and quantified the responses of a number of clones and life stages to varying levels of starvation, in the form of increasingly desiccated Vicafaba L. plants （receiving 50, 25, or 10 mL every second day） or a complete absence of host plant. We found that, while the longest incidences of cannibalism are carried out by juveniles （F = 3.45, P = 0.019, df = 3） and targeted at adults, the starvation treatments had the most significant effect on the prevalence of cannibalism in mature A. pisum （F ---- 2.24, P = 0.025, df = 9）. Furthermore, there was no difference between the prevalence or dura- tion of cannibalistic activities within and between different clones （P 〉 0.05 in all cases）, though juveniles were more likely to target unrelated aphids （V = 6 112, P = 0.011）, and spent more time feeding on aphids from the same culture （V = 6 062, P = 0.018）.展开更多
文摘This study examines the optimal pricing and production strategy of a closed-loop supply chain consisting of a manufacturer, a recycler, and consumers. Considering the cannibalization and promotion effects of remanufactured products on new and secondhand products, we constructed Stackelberg game models under different scenarios. We analyze the impact of the changes in the two effects on the optimal prices and production strategies of the manufacturer and recycler, as well as their countermeasures. We find that (i) how the cannibalization and promotional effects influence the manufacturer and the recycler's pricing and production strategies differ under different scenarios;(ii) when the two effects exceed a threshold, the manufacturer abandons new or remanufactured products, and the recycler prefers to stop production on its new products or continue to remanufacture products;and (iii) the two effects always reduce the profits of the manufacturer and increase the profits of the recycler.
基金Fundamental Research Grant Scheme from the Ministry of Higher Education,Malaysia(No.59324)。
文摘Ecdysis is a comm on phe nomenon that happe ns throughout the life phase of the giant freshwater prawn Macrobrachium rosenbergii.It is vital to better understand the correlation between cannibalism and biochemical compound that exists during the moulting process.The objective of the present study was to determine the amino acid profile released by M.rosenbergii during the ecdysis process that promotes cannibalism.To accomplish this,changes in amino acid levels(total amino acid(TAA)and free amino acid(FAA))of tissue muscle,exoskeleton,and sample water of culture medium from the moulting(E-stage)and non-moulting(C-stage)prawns were analysed using highperformanee liquid chromatography(HPLC).Comparison study revealed that among the TAA compounds,proline and sarcosine of tissues from moulting prawn were found at the highest levels.The level of FAA from water that contains moulting prawns(E-stage)was dominated by tryptophan and proline.Significant values obtained in the present study suggested that these amino acid compounds act as a chemical cue to promote cannibalism in M.rosenbergii during ecdysis.The knowledge of compositions and compounds that were released during the moulting process should be helpful for better understanding of the mechanism and chemical cues that play roles on triggering cannibalism,and also for future dietary man ipulati on to improve feeding efficie ncies and feeding man agement,which in directly impacts productivity and profitability.
基金supported by the Strategic Priority Research Program of the Chinese Academy of Sciences(XDB31000000) to S.Q.L。
文摘Although widely thought to be aggressive, solitary,and potentially cannibalistic, some spider species have evolved group-living behaviors. The distinct transition provides the framework to uncover groupliving evolution. Here, we conducted a comparative transcriptomic study and examined patterns of molecular evolution in two independently evolved group-living spiders and twelve solitary species. We report that positively selected genes among groupliving spider lineages are significantly enriched in nutrient metabolism and autophagy pathways. We also show that nutrient-related genes of group-living spiders convergently experience amino acid substitutions and accelerated relative evolutionary rates. These results indicate adaptive convergence of nutrient metabolism that may ensure energy supply in group-living spiders. The decelerated evolutionary rate of autophagy-related genes in group-living lineages is consistent with an increased constraint on energy homeostasis as would be required in a group-living environment. Together, the results show that energy metabolic pathways play an important role in the transition to group-living in spiders.
文摘Wood frog Lithobates sylvaticus tadpoles develop in temporary wetlands where high population densities can force tadpoles into aggregations that intensify competition and can lead to cannibalism. However, chemical alarm cues released from injured conspecifics could also dissuade cannibalism. The purpose of this study was to test mechanisms that may influence can- nibalistic behaviour. We tested whether the tendency of tadpoles to consume conspecifics would increase with the presence of competition and/or cues of profitable diets. Tadpoles placed in 1L experimental containers were tested for feeding initiation times of multiple diets, including conspecific tissues and conspecific tissues combined with chemical cues from the alternative diets （brine shrimp and comrneal）. Tadpoles were tested in the presence and absence of a competitor, and at multiple times over the course of the study. Tadpoles exhibited an altered response to diets over time; however the presence of a competitor reduced re- sponse times to all diets including conspecific tissues. Similarly, the presence of specific diets also reduced the response time of tadpoles to conspecific tissues. These results suggest competition among feeding tadpoles could result in aggressive behaviour leading to indiscriminate predation and cannibalism [Current Zoology 60 （5）： 571-580, 2014 ].
文摘The present study examines the inherent flexibility in the feeding responses of S. infraimmaculata larvae to various breeding places. In addition, the study examines the hypothesis that in dry conditions, the water breeding places are the limiting factor for the survival and completion of the life cycle of populations of S. infraimmaculata. In the breeding sites, the food for larvae is not available, and cannibalism is the specific adaptation for larvae to grow and complete metamorphosis. S. infraimmaculata larvae feed on various invertebrates in different habitats, and cannibalism involves the adaptation to breeding places where food is not available. The growth only by cannibalism as the only way to adapt to these habitats because no food is found in breeding places at the southern border of its distribution is described here for the first time, not only in salamanders but in other animals as well.
文摘Larval growth and survival of organisms are strongly influenced by abiotic and biotic factors, as demonstrated by ex- perimental studies performed under controlled laboratory or semi-natural conditions. Even if they have many advantages, ex- periments cannot cover the full complexity of natural conditions and field studies are needed for a better understanding of how environmental variation determines growth and development rate. Fire salamander Salamandra salamandra females give birth to larvae in a variety of habitats, both epigean and subterranean. In caves, salamander larvae successfully grow and metamorphose, but their growth is more than three times longer than in epigean streams and factors determining these differences require inves- tigation. We performed a field study to understand the factors related to the growth of fire salamander larvae in different envi- ronmental conditions, evaluating the relationship between environmental features and larval growth and differences between caves and epigean spring habitats. Both caves and epigean larvae successfully grew. Capture-mark-recapture allowed to individu- ally track individuals along their whole development, and measure their performance. Growth rate was significantly affected by environmental variables： larvae grew faster in environments with abundant invertebrates and few conspeciflcs. Taking into ac- count the effect of environmental variables, larval growth was significantly lower in caves. Food availability plays a different ef- fect in the two environments. Larval growth was positively related to the availability of invertebrates in epigean sites only. The development rate of hypogeous populations of salamanders is slower because of multiple parameters, but biotic factors play a much stronger role than the abiotic ones
基金This study was supported in part by New Zealand Government core funding for Crown Research Institutes from the Ministry of Business,Innovation and Employment’s Science and Innovation Group.
文摘Kin recognition has been widely observed in various taxa.Cannibalism avoidance may be a strong driver for the evolution of kin recognition,as it may avoid a reduction in inclusive fitness.Kin recognition has recently been observed in a generalist phytoseiid,Amblyseius herbicolus(Acari:Phytoseiidae).This study experimentally examined the degree of relatedness needed between prey larvae and cannibal adults of A.herbicolus for the occurrence of kin discrimination.The adults were individually placed in enclosed arenas with two prey,a daughter and a more distant related larva,to observe their cannibalizing choice.The adults of A.herbicolus did not discriminate between close relatives(daughter versus niece)but preferably cannibalized more distant kin(i.e.,first and second cousins once removed).Phenotype matching and familiarization seem prominent as recognition mechanisms used by A.herbicolus adults.The effect of learning on kin recognition through prior contact in A.herbicolus requires further investigation.Studies on other adaptive functions of kin recognition of A.herbicolus,such as cooperation and parental care,may provide meaningful insights.
基金This work was supported by grants from the National Natural Science Foundation of China(NSFC-31801979 and 31872229)the Singapore Ministry of Education(MOE)AcRF Tier 1 grant(R-154-000-B18-114).
文摘Sexual conflict is common in animals,and female sexual cannibalism represents an extreme form of sexual conflict.Males in many species have evolved a variety of strategies to circumvent or decrease the risk of female sexual cannibalism.Opportunistic mating,by which a male mates with a female when she is disturbed or when she is feeding or undertaking moulting,is one of such kinds of strategies,and widely occurs in many animals,especially in spiders.However,whether the occurrence of male opportunistic mating depends on the intensity of female sexual cannibalism remains largely unexplored.We predicted a positive correlation between them.In this study,we tested this prediction by performing a series of mating trials in the laboratory using 3 species of web-building spiders with different intensities of female sexual cannibalism:Nephila pilipes,Nephilengys malabarensis,and Parasteatoda tepidariorum.We found that the occurrence of male opportunistic mating was positively,though not statistically significantly,correlated with the intensity of female sexual cannibalism,thus supporting our hypothesis.All together,we provide evidence that male opportunistic mating may have evolved to respond to the selection pressure posed by female sexual cannibalism.
文摘As one of the representative contemporary Asian American poets, Li-Young Lee in his two poetry collections entitled Rose and The Cify in Which 1Love You, recuperates his fragmented family history of immigration, and reconstructs a dynamic relationship with remembrance of the past that writes about him and defines his sense of self. This paper from the multicultural perspective argues that understanding the past through understanding his godlike father, Lee not only negotiates the formation of his subjectivity and identity, but also establishes a spiritual origin and belonging not merely with his ethnic communities but with all the immigrants as well. The paper finds that the strategy he employs in his articulation of his self is marked by his excellent execution of poetic epiphany, and metonymic cannibalism.
文摘The launching of a new product is an essential strategy for the survival and success of a company. However, in certain cases, it can reduce the results obtained by other products of the same company. This fact is named ＂cannibalism＂. Following by a review of the literature on cannibalism between goods, this paper outlines a conceptual approach, showing the way it happens, its impacts, and the possibility of its uses as a marketing tool. A new product should, wherever possible, be carefully designed to avoid cannibalizing old products, unless this process is carefully planned. Concludes that creating and launching of new products are critical to companies who want to stand out next to their markets and need to survive over time. A lot of new products launched each year, coupled with the fact that most are line extensions already worked by companies, so we assume that the occurrence of cannibalism is common, or that a significant amount of resources are designed to prevent or dilute it. There is a high probability of transfer of results obtained by established products to new products, since similarity between
文摘Good brand name translation involves knowledge and expertise from many disciplines,such as linguistics,translation studies,marketing,aesthetics,psychology,law,etc.It is really an interdisciplinary practice that requires strenuous research and experience.In addition,the research methodology thereof is also quite problematic.This paper aims at bringing a latest translation theory—cannibalism into brand name translation and test its applicability in brand name translation practice.
文摘At the end of the eighteenth century in Britain,due to the development of capitalism,money has become more and more important.Jane Austen describes in the Sense and Sensibility that under the influence of money,people's values have become dis⁃torted,such as some have become family cannibalism,and some have become betrayers of love.At the same time,Austen also ex⁃presses her attitude towards money which gives us a lot of enlightenment.
文摘In this paper, we consider the fear effect and gestation delay, and then establish a delayed predator-prey model with cannibalism. Firstly, we prove the well-posedness of the model. Secondly, the existence and stability of all equilibriums of the system are studied. Thirdly, the Hopf bifurcation at the coexistence equilibrium is investigated, and the conditions for the occurrence of Hopf bifurcation at the unique positive equilibrium point of the system with delay are determined. Finally, the numerical simulation results show that as the time delay increases, the equilibrium loses its stability, and the system has periodic solution.
基金supported by the European Commission H2020-MSCA-RISE 2019(872767)the National Natural Science Foundation of China(32370475)+1 种基金the Biological taxonomist,Chinese Academy of Sciences(CAS-TAX-24-037)by the University of Pisa,PRA_2018_63 project.
文摘Two populations of the kentrurostylid ciliate Pseudokeronopsis erythrina Chen et al.,2011 were isolated from a brackish wastewater treatment plant,Pisa,Italy and from a nutrient-rich freshwater body,the East Lake,Wuhan,China.The populations were thoroughly investigated for their morphology,focusing on cell body plasticity.The study was supplemented with 18S rDNA phylogenetic analysis and mitogenome sequencing,following the integrative taxonomy approach.The Italian population possesses a great variation in terms of the frontal area,and the numbers of left marginal rows,and dorsal kineties.Additionally,the number of left marginal anlagen and dorsal kineties anlagen varied.For instance,additional small anlagen appeared in the left marginal rows,and two dorsal kineties anlagen derived from a single dorsal kinety.The Wuhan population resembled the type population(originally isolated from Guangzhou,China),differing only by the presence of an extra dorsal kinety.The existence of giant individuals characterized both new populations of P.erythrina although with some differences in their respective frequency and features.The 18S rDNA sequences of the Italian,Wuhan,and type populations were identical.Phylogenetic analyses showed that these three populations formed a distinct cluster within the clade containing P.songi,P.parasongi,and P.flava.The structure of the P.erythrina mitochondrial genome is also provided.The content of this genome closely resembled Pseudourostyla cristata,except for the absence of genes nadh3 and nadh6.Our findings suggest that the Wuhan population represents an intermediate form between the type and Italian populations.The greater morphological plasticity observed in the Italian population underscores the importance of molecular data and integrative analyses in species identification.
基金The work was supported by National Natural Foundation of China(grant number 31972296,31830075,and 32172482).
文摘Maternal care is critically important for the survival of offspring in various animals.Spiders in the family Lycosidae are known for their hunting ability and maternal care behaviors.Predation on newly hatched spiderlings(pulli)by mother spiders decreases when they come into contact,and they carry the pulli on their dorsal surface.However,the factors inducing maternal care in lycosid spiders have not been elucidated.In this study,we investigated maternal care in Pardosa pseudoannulata(Araneae,Lycosidae)females.We proposed that the physical interaction between pulli and mother spiders induces maternal care via m-aminophenylacetylene(m-A),a novel regulator of maternal care.The presence of pulli on the dorsal abdomen of non-mother spiders suppressed pulli predation and in-creased the pulli-carrying rate,and the absence of pulli on the mother spiders increased pulli predation and decreased the pulli-carrying rate.The compound m-A was abundant in mother spiders,and it could be induced in non-mother spiders when they carried pulli.The topical application of m-A to non-mother spiders and m-A injection decreased pulli predation and increased the pulli-carrying rate,respectively;these findings indicate that m-A in both internal tissues and the integument is required for the induction of mater-nal care behavior,and the interaction between pulli and females induces the production of m-A.In-depth study of the regulatory mechanism of maternal care will enhance our understanding of spider biology and behavior.
基金Supported by Beijing Natural Science Foundation(9212020)National Natural Science Foundation of China(72172145,71932002)the Fundamental Research Funds for the Central Universities。
文摘With the rapid development of e-Commerce and takeaway platforms, retailers have gradually developed multi-channel operations. However, limited empirical studies explored the effects of an online channel offered by takeaway platforms on the store performance. Does an online channel addition have a synergy effect or a cannibalization effect on store performance? We empirically investigate these effects by analyzing a large dataset including diverse samples collected from multiple retailers across various regions. The dataset includes 2115 stores across 25 retailers for 10 months that includes two types of retail formats and covers 16 provinces and 21 cities of China. We study the impacts of the newly introduced online channel on the incumbent offline channel and the overall store performance.The empirical results reveal that the online channel addition mainly has a synergy effect. Specifically,for the overall store, it has a positive effect on the sales and product variety, whereas it has a negative effect on the basket size. Surprisingly, an online channel addition also has a positive effect on the offline sales. Our study adds novel values to multi-channel retailing literature by empirically researching the cannibalization and synergy effect of a new type of online channel, offered by takeaway platforms. It can provide insights for retail enterprises who are interested in introducing O2 O model.
文摘In technology-intensive markets, it is a common strategy for companies to develop long-term multiple generation product lines instead of releasing consecutive single products. Even though this strategy is more profitable than sequentially introducing single product generations, it can also result in inter-product line cannibalization. Cannibalization of multiple-generation product lines is a complex problem that needs to be taken into account at the early product line planning stage in order to sustain long-term profitability. In this paper, we propose an agent-based model that can simulate the potential cannibalization scenarios within a multiple-generation product line. We view a multiple-generation product line （MGPL） as complex adaptive system where each product generation in the MGPL adjusts its sales price over time based on the shifts in the market demand. The proposed model provides insights into how various pricing strategies impact the overall lifecycle profitability of MGPL and can be used to assist companies in developing appropriate dynamic pricing strategies at the early product line planning stages.
文摘Cannibalism is an intriguing life history trait, that has been considered primarily in the predator, in predator-prey population models. Recent experimental evidence shows that prey cannibalism can have a significant impact on predator-prey population dyna- mics in natural communities. Motivated by these experimental results, we investigate a ratio-dependent Holling-Tanner model, where cannibalism occurs simultaneously in both the predator and prey species. We show that depending on parameters, whilst prey or predator cannibalism acting alone leads to instability, their joint effect can actually stabilize the unstable interior equilibrium. Furthermore, in the spatially explicit model, we find that depending on parameters, prey and predator cannibalism acting jointly can cause spatial patterns to form, while not so acting individually. We discuss ecologicalconsequences of these findings in light of food chain dynamics, invasive species control and climate change.
文摘Previous observations of cannibalism have been made in the aphid Acyrthosiphon pisum （L.）： this article seeks to quantify factors contributing to such be- haviors. We observed and quantified the responses of a number of clones and life stages to varying levels of starvation, in the form of increasingly desiccated Vicafaba L. plants （receiving 50, 25, or 10 mL every second day） or a complete absence of host plant. We found that, while the longest incidences of cannibalism are carried out by juveniles （F = 3.45, P = 0.019, df = 3） and targeted at adults, the starvation treatments had the most significant effect on the prevalence of cannibalism in mature A. pisum （F ---- 2.24, P = 0.025, df = 9）. Furthermore, there was no difference between the prevalence or dura- tion of cannibalistic activities within and between different clones （P 〉 0.05 in all cases）, though juveniles were more likely to target unrelated aphids （V = 6 112, P = 0.011）, and spent more time feeding on aphids from the same culture （V = 6 062, P = 0.018）.
