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Caprine Arthritis Encephalitis is an endemic disease in goat breedings, caused by viral strains belonging to the Small Ruminant Lentivirus group and characterized by a progressive chronic course. Its clinical signs are not immediately recognizable and can only be detected via costly serological tests. No vaccine is available. Two main strategies for fighting it are in common use. The “test-and-slaughter” approach, that selects infected goats and directly slaughters them, is expensive, time consuming and often leads to endemic low level persistence of the infection. Alternatively, newborns are removed from their mothers to be raised by healthy goats. After weaning they would rejoin their breeds, but then they could still be subject to horizontal contagion. In this study a mathematical model that considers the cocirculation of two different SRLV viral genotypes (B and E) is devised and analyzed, based on the key assumption of perfect cross-protection between the two genotypes’ infections. Two strategic measures arise from its analysis, that are strongly recommended and whose implementation is encouraged: in the presence of both genotypes, the farmer should not isolate the newborns from their mothers but rather raise them with all the other animals. In the case of genotype-B-only affected farm, serological testing and mother-offspring separation should still be considered the best strategy for CAEV control. These strategies completely reverse the current removal policy and, in due conditions, would lead to disease eradication. These represent very reasonable and cheap measures for the eventual control of the epidemics.

A study of the architectural tradition of the types and spaces used to teach fine arts underlays the research to develop the Accademia di Brera project at the Farini marshalling yard, a brand-new campus for the arts as part of the urban regeneration of the whole of the former marshalling yard area. The system, which uses different varieties of newly built multiple teaching spaces, is inserted into the existing long galleries which feature frame construction.

Diseases affecting farmed cattle compromise both human and animal health and welfare, and represent a major cause of loss in economic revenue. Their spread is known to be driven, or at least facilitated, by animal displacements among livestock holdings, both within and across countries. As a result, studying the networks of animal movements is a key step in devising new prevention and containment strategies. Past works have already analyzed cattle networks in several European countries, highlighting complex interactions between topology, function and dynamics at different spatial and time resolutions. A comprehensive study, showing the impact of country-specific driving factors on network evolution and topology, is however still missing. By using data from several European countries, and focusing on the features relevant for the spread of infections, we perform a comparative analysis to highlight both general and country-specific patterns. We find that coarse-graining the structure into statistical distributions of centrality measures is an effective way to highlight the properties shared by all networks, which represent the fingerprint of a livestock market. The situation dramatically changes when we zoom in to the microscopic structure, as we find several country-specific characteristics, especially in temporal evolution. This twofold behavior suggests that on one hand it is possible to identify several global patterns in the ways animal disease spread, which can then be applied to countries for which data are unavailable, or incomplete. On the other hand, resolved country-specific data are needed when devising tailored and targeted intervention strategies

Spirochetes belonging to the Borrelia burgdoferi sensu lato (sl) group cause Lyme Borreliosis (LB), which is the most commonly reported vector-borne zoonosis in Europe. B. burgdorferi sl is maintained in nature in a complex cycle involving Ixodes ricinus ticks and several species of vertebrate hosts. The transmission dynamics of B. burgdorferi sl is complicated by the varying competence of animals for different genospecies of spirochetes that, in turn, vary in their capability of causing disease. In this study, a set of difference equations simplifying the complex interaction between vectors and their hosts (competent and not for Borrelia) is built to gain insights into conditions underlying the dominance of B. lusitaniae (transmitted by lizards to susceptible ticks) and the maintenance of B. afzelii (transmitted by wild rodents) observed in a study area in Tuscany, Italy. Findings, in agreement with field observations, highlight the existence of a threshold for the fraction of larvae feeding on rodents below which the persistence of B. afzelii is not possible. Furthermore, thresholds change as nonlinear functions of the expected number of nymph bites on mice, and the transmission and recovery probabilities. In conclusion, our model provided an insight into mechanisms underlying the relative frequency of different Borrelia genospecies, as observed in field studies., 14 pages, 3 figures, to be published in Theoretical Population Biology

In order to investigate the behaviour of athletes in choosing sports, we analyse data from part of the We-Sport® database, a vertical social network that links athletes through sports. In particular, we explore connections between people sharing common sports and the role of age and gender by applying “network science” approaches and methods. The results show a disassortative tendency of athletes in choosing sports, a negative correlation between age and number of chosen sports and a positive correlation between age of connected athletes. Some interesting patterns of connection between age classes are depicted. In addition, we propose a method to classify sports, based on the analyses of the behaviour of people practising them. Thanks to this brand new classifications, we highlight the links of class of sports and their unexpected features. We emphasise some gender dependency affinity in choosing sport classes.

A model for the genotype B Caprine Arthritis Encephalitis virus disease is presented.Only endemic and disease-free equilibria arise, and a transcritical bifurcation.Eradication is possible only for very small economically unaffordable herds.In absence of vaccination new strategies for fighting the disease are needed. In this paper we analyze the Caprine Arthritis Encephalitis virus disease. We construct a very general model for its epidemiology, for the case when the disease is caused only by a specific viral strain, called the genotype B. The model has only the endemic and the disease-free equilibria, with a transcritical bifurcation connecting the two. Eradication based on this analysis is possible only for very small herds, so that it can hardly be considered economically affordable. The study suggests that in absence of control measures new means of fighting the disease are needed, paving the road for further theoretical and field work.

Spatial ecoepidemic models, in which diseases affect interacting populations, are often explored through reaction-diffusion equations. However, cellular automata (CA) are a widely recognized tool for modelling spatial pattern formation that are broadly analagous to reaction diffusion equations, but provide greater flexibility in defining population dynamics. In this work we present a CA defined to mimic the prey–predators interactions while a pathogen is affecting, in turn, one population. We explore system equilibria, given different initial conditions and local interaction neighborhoods. Furthermore, in the various ecoepidemic systems considered we report the formation of waves and spirals: a key summary of how diseases may spread among individuals. Some inferences on the predators and infection eradication strategies are presented and supported by simulations results.

Tick-Borne diseases can be transmitted via non-systemic (NS) transmission. This occurs when tick gets the infection by co-feeding with infected ticks on the same host resulting in a direct pathogen transmission between the vectors, without infecting the host. This transmission is peculiar, as it does not require any systemic infection of the host. The NS transmission is the main efficient transmission for the persistence of the Tick-Borne Encephalitis virus in nature. By describing the heterogeneous ticks aggregation on hosts through a \hyphenation{dynamical} bipartite graphs representation, we are able to mathematically define the NS transmission and to depict the epidemiological conditions for the pathogen persistence. Despite the fact that the underlying network is largely fragmented, analytical and computational results show that the larger is the variability of the aggregation, and the easier is for the pathogen to persist in the population., 15 pages, 4 figures, to be published in Communications in Nonlinear Science and Numerical Simulation

The Controller Area Network (CAN) has been adopted as the network communication technology of choice in many real-time application domains. Due to the ever increasing sophistication of contemporary embedded controllers, it becomes both possible and convenient to access this kind of network by means of a well-known and standard application programming interface instead of resorting to an ad hoc framework. This paper describes the addition of CAN support to the eCos embedded real-time operating system, from the device interface layer up to the extension of its network communication modules, based on Berkeley sockets.

The structure of a network dramatically affects the spreading phenomena unfolding upon it. The contact distribution of the nodes has long been recognized as the key ingredient in influencing the outbreak events. However, limited knowledge is currently available on the role of the weight of the edges on the persistence of a pathogen. At the same time, recent works showed a strong influence of temporal network dynamics on disease spreading. In this work we provide an analytical understanding, corroborated by numerical simulations, about the conditions for infected stable state in weighted networks. In particular, we reveal the role of heterogeneity of edge weights and of the dynamic assignment of weights on the ties in the network in driving the spread of the epidemic. In this context we show that when weights are dynamically assigned to ties in the network, a heterogeneous distribution is able to hamper the diffusion of the disease, contrary to what happens when weights are fixed in time.

In this work we analyze the complexity of a disease that spreads among two populations and in which the transmission routes are available only throught individuals of the two different families. This peculiar route is typical of diseases such as sexual transmitted diseases on heterosexual populations or vector-host diseases such as tick-borne encephalitis or Lyme borreliosis. In such epidemiological scenarios, the contact network is naturally represented by a bipartite graphs. In this article we determine that a pathogen agent spreading on a bipartite network can have some evolutionary benefits with respect to diffusing on standard unipartite networks.