10 research outputs found

    Serological detection of antibodies against Paracoccidioides brasiliensis in dogs with leishmaniasis

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    The aim of this study was to detect antibodies against Paracoccidioides brasiliensis in dogs seropositive and seronegative for leishmaniasis. Sera from 836 dogs (449 positive and 387 negative to leishmaniasis) were analysed by ELISA and the immunodiffusion test using gp43 and exoantigen, respectively. The analysis of the 836 serum samples by ELISA and the immunodiffusion test showed a positivity of 67.8 % and 7.3%, respectively, for P. brasiliensis infection. The dogs positive to leishmaniasis showed a higher reactivity to gp43 (79.9%) and exoantigen (12.7%) than the negative ones (54.0% and 1.0%, respectively). The higher reactivity to P. brasiliensis antigens may be due to cross-reactivity or a co-infection of dogs by Leishmania and P. brasiliensis. The lower correlation (0.187) observed between reactivity to gp43 and Leishmania antigen reinforces the latter hypothesis

    Arc routing for parking enforcement officers : exact and heuristic solutions

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    This paper presents exact and approximate methods for constructing daily walking tours for parking enforcement officers the Parking Enforcement Routing Problem (PERP), a problem faced by EMEL, a municipal company that manages parking in Lisbon. Parking Enforcement Officers (PEO) must ensure that the users of the street parking lots pay the corresponding fee, and that they also comply with the parking rules imposed by the legislation in force. The duration of the tours must be compatible with the PEO daily work schedules. A street cannot be supervised more than once in consecutive hours, nor supervised simultaneously by two PEOs. The PERP is a new generalisation of an Arc Routing Problem with profits aiming to maximise the total criticality, a concept defined to represent the need for enforcement of the street segments, related to the number of vehicles parked in transgression. Moreover, parking rules lead to some specificities regarding the underlying network, which needs to be built with additional unusual characteristics. A flow-based mixed integer linear programming model and heuristics which return two daily trips for each PEO are proposed. Computational results carried out on 50 instances based on real data show that it was appropriate to propose both types of methods, exact and heuristic. Furthermore, PEOs working for EMEL reacted positively to the trips corresponding to the generated solutions. A Decision Support System built on the heuristics was also developed to be easily used by practitioners in EMELinfo:eu-repo/semantics/publishedVersio
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