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The Association between Virus Prevalence and Intercolonial Aggression Levels in the Yellow Crazy Ant, Anoplolepis Gracilipes (Jerdon).
The recent discovery of multiple viruses in ants, along with the widespread infection of their hosts across geographic ranges, provides an excellent opportunity to test whether viral prevalence in the field is associated with the complexity of social interactions in the ant population. In this study, we examined whether the association exists between the field prevalence of a virus and the intercolonial aggression of its ant host, using the yellow crazy ant (Anoplolepis gracilipes) and its natural viral pathogen (TR44839 virus) as a model system. We delimitated the colony boundary and composition of A. gracilipes in a total of 12 study sites in Japan (Okinawa), Taiwan, and Malaysia (Penang), through intercolonial aggression assay. The spatial distribution and prevalence level of the virus was then mapped for each site. The virus occurred at a high prevalence in the surveyed colonies of Okinawa and Taiwan (100% infection rate across all sites), whereas virus prevalence was variable (30%-100%) or none (0%) at the sites in Penang. Coincidentally, colonies in Okinawa and Taiwan displayed a weak intercolonial boundary, as aggression between colonies is generally low or moderate. Contrastingly, sites in Penang were found to harbor a high proportion of mutually aggressive colonies, a pattern potentially indicative of complex colony composition. Our statistical analyses further confirmed the observed correlation, implying that intercolonial interactions likely contribute as one of the effective facilitators of/barriers to virus prevalence in the field population of this ant species
Asymmetrically interacting spreading dynamics on complex layered networks
The spread of disease through a physical-contact network and the spread of
information about the disease on a communication network are two intimately
related dynamical processes. We investigate the asymmetrical interplay between
the two types of spreading dynamics, each occurring on its own layer, by
focusing on the two fundamental quantities underlying any spreading process:
epidemic threshold and the final infection ratio. We find that an epidemic
outbreak on the contact layer can induce an outbreak on the communication
layer, and information spreading can effectively raise the epidemic threshold.
When structural correlation exists between the two layers, the information
threshold remains unchanged but the epidemic threshold can be enhanced, making
the contact layer more resilient to epidemic outbreak. We develop a physical
theory to understand the intricate interplay between the two types of spreading
dynamics.Comment: 29 pages, 14 figure
The Selection Model for Compound or Portfolio Relationships Oriented in Supply Chain
As the environment changed, the inter-organizat ional in Supply chain has been transferred fro m simple relations to complex relations āComp ound or Portfolio Relationshipsā. The main pur pose of this research is to integrate external/int ernal resource and maintain flexible volatility o f inter-organization for helping organizations/fir ms could increase the competitive advantage fo r them. To survey the current researches which discuss inter-organization in supply chain; it c ould be found that most literatures are focused on each simple relationship or portfolio relatio nship about their types and features. Our resear ch uses multiple relative theory and interviews to perform the research. To develop theory mo del and analyse the nature of relations about c ompound relationships oriented and portfolio rel ationships oriented. The theoretical framework model concerns the influence of the difference selection factors between inter-organizational in supply chain. We hope this research will cont ribute to further studies and provide some sugg estions for implementing management of the rel ationship between supply chains
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