The Gambian Epauletted Fruit Bat Shows Increased Genetic Divergence in the Ethiopian Highlands and in an Area of Rapid Urbanisation

The Gambian epauletted fruit bat (Epomophorus gambianus) is an abundant species that roosts in both urban and rural settings. The possible role of E. gambianus as a reservoir host of zoonotic diseases underlines the need to better understand the species movement patterns. So far, neither observational nor phylogenetic studies have identified the dispersal range or behavior of this species. Comparative analyses of mitochondrial and nuclear markers from 20 localities across the known distribution of E. gambianus showed population panmixia, except for the populations in Ethiopia and southern Ghana (Accra and Ve‐Golokwati). The Ethiopian population may be ancestral and is highly divergent to the species across the rest of its range, possibly reflecting isolation of an ancient colonization along an east–west axis. Mitochondrial haplotypes in the Accra population display a strong signature of a past bottleneck event; evidence of either an ancient or recent bottleneck using microsatellite data, however, was not detected. Demographic analyses identified population expansion in most of the colonies, except in the female line of descent in the Accra population. The molecular analyses of the colonies from Ethiopia and southern Ghana show gender dispersal bias, with the mitochondrial DNA fixation values over ten times those of the nuclear markers. These findings indicate free mixing of the species across great distances, which should inform future epidemiological studies

Phylogeography and demographic history of Epomophorus gambianus: contrasting nuclear and mitochondrial DNA

The Gambian epauletted fruit bat (Epomophorus gambianus) is an abundant species that roosts in both urban and rural settings. The possible role of E. gambianus as a reservoir host of zoonotic diseases underlines the need to better understand the species movement patterns. So far, neither observational nor phylogenetic studies have identified the dispersal range or behavior of this species. Comparative analyses of mitochondrial and nuclear markers from 20 localities across the known distribution of E. gambianus showed population panmixia, except for the populations in Ethiopia and southern Ghana (Accra and Ve‐Golokwati). The Ethiopian population may be ancestral and is highly divergent to the species across the rest of its range, possibly reflecting isolation of an ancient colonization along an east–west axis. Mitochondrial haplotypes in the Accra population display a strong signature of a past bottleneck event; evidence of either an ancient or recent bottleneck using microsatellite data, however, was not detected. Demographic analyses identified population expansion in most of the colonies, except in the female line of descent in the Accra population. The molecular analyses of the colonies from Ethiopia and southern Ghana show gender dispersal bias, with the mitochondrial DNA fixation values over ten times those of the nuclear markers. These findings indicate free mixing of the species across great distances, which should inform future epidemiological studies

Post-glacial colonisation of Europe by the wood mouse, Apodemus sylvaticus : evidence of a northern refugium and dispersal with humans

The wood mouse Apodemus sylvaticus is an opportunistic rodent that is found throughout most of the European mainland. It is present on many islands around the margins of the continent and in northern Africa. The species has been the subject of previous phylogeographic studies but these have focussed on the more southerly part of its range. A substantial number of new samples, many of them from the periphery of the species’ range, contribute to an exceptional dataset comprising 981 mitochondrial cytochrome b sequences. These new data provide sufficient resolution to transform our understanding of the species’ survival through the last glaciation and its subsequent re-colonisation of the continent. The deepest genetic split we found is in agreement with previous studies and runs from the Alps to central Ukraine, but we further distinguish two separate lineages in wood mice to the north and west of this line. It is likely that this part of Europe was colonised from two refugia, putatively located in the Iberian peninsula and the Dordogne or Carpathian region. The wood mouse therefore joins the growing number of species with extant populations that appear to have survived the Last Glacial Maximum in northern refugia, rather than solely in traditionally recognised refugial locations in the southern European peninsulas. Furthermore, the existence of a northern refugium for the species was predicted in a study of mitochondrial variation in a specific parasite of the wood mouse, demonstrating the potential value of data from parasites to phylogeographic studies. Lastly, the presence of related haplotypes in widely disparate locations, often on islands or separated by substantial bodies of water, demonstrates the propensity of the wood mouse for accidental human-mediated transport

The Impact of Human Conflict on the Genetics of Mastomys natalensis and Lassa Virus in West Africa

Environmental changes have been shown to play an important role in the emergence of new human diseases of zoonotic origin. The contribution of social factors to their spread, especially conflicts followed by mass movement of populations, has not been extensively investigated. Here we reveal the effects of civil war on the phylogeography of a zoonotic emerging infectious disease by concomitantly studying the population structure, evolution and demography of Lassa virus and its natural reservoir, the rodent Mastomys natalensis, in Guinea, West Africa. Analysis of nucleoprotein gene sequences enabled us to reconstruct the evolutionary history of Lassa virus, which appeared 750 to 900 years ago in Nigeria and only recently spread across western Africa (170 years ago). Bayesian demographic inferences revealed that both the host and the virus populations have gone recently through severe genetic bottlenecks. The timing of these events matches civil war-related mass movements of refugees and accompanying environmental degradation. Forest and habitat destruction and human predation of the natural reservoir are likely explanations for the sharp decline observed in the rodent populations, the consequent virus population decline, and the coincident increased incidence of Lassa fever in these regions. Interestingly, we were also able to detect a similar pattern in Nigeria coinciding with the Biafra war. Our findings show that anthropogenic factors may profoundly impact the population genetics of a virus and its reservoir within the context of an emerging infectious disease

Flexible Deployment and Enforcement of Flight and Privacy Restrictions for Drone Applications

As drones gradually become a key component of next-generation cyber-physical systems, it is important to manage them in a flexible and efficient way. At the same time, it is crucial to enforce certain restrictions, which may not only concern no-fly zones but may also limit the usage of specific sensors, especially in urban areas. To this end, we propose an open system that enables the flexible deployment and controlled execution of drone applications. On the one hand, applications come in the form of independently executable software bundles that can be deployed on whichever drones are available and satisfy the corresponding resource and flight requirements. On the other hand, suitable mechanisms are used to monitor the execution of the applications at runtime in order to check conformance to the restrictions posed by the authorities, as well as to handle related violations in an automated way. In this paper, we present the key elements of the proposed approach and describe a proof-of-concept implementation that supports most of the envisioned functionality. We also provide a validation of our system prototype using both a software-in-the-loop setup and a real drone in the open. © 2020 IEEE

Fractus: Orchestration of Distributed Applications in the Drone-Edge-Cloud Continuum

Next-generation drone applications will be distributed, including tasks that need to run at the edge or in the cloud and interact with the drone in a smooth way. In this paper, we propose Fractus, an orchestration framework for the automated deployment of such applications in the drone-edge-cloud continuum. Fractus provides users with abstractions for describing the application's placement and communication requirements, allocates resources in a mission-aware fashion by considering the drone operation area, establishes and maintains connectivity between components by transparently leveraging different networking capabilities, and tackles safety and privacy issues via policy-based access to mobility and sensor resources. We present the design of Fractus and discuss an implementation based on mature software deployment technology. Further, we evaluate the resource requirements of our implementation, showing that it introduces an acceptable overhead, and illustrate its functionality via real field tests and a simulation setup. © 2022 IEEE

A market-based protocol with leasing support for globally distributed computing

We have developed JaWS, a Java-based Web computing system, which enables users to effortlessly export their machines in a global market of processing capacity to host remote computations (S. Lalis and A. Karipidis, 2000). Leases are used to promote dynamic task placement as well as fair compensation for the host providers. The authors present an updated protocol used by hosts and applications to interact with the JaWS market, through which resource allocation takes place. Although this work is carried out in the context of JaWS, it can also be applied to other market-based resource allocation frameworks. © 2001 IEEE