André Santos

Role of the Lizard Teira dugesii as a Potential Host for Ixodes ricinus Tick-Borne Pathogens

ABSTRACT PCR screening of ticks and tissue samples collected from 151 Teira dugesii lizards seems to indicate a potential role of this lizard species in the maintenance and transmission cycle of some Ixodes ricinus tick-borne agents, such as Rickettsia monacensis, Rickettsia helvetica, and Borrelia lusitaniae, that are circulating on Madeira Island.

Evidence of Bartonella spp., Rickettsia spp. and Anaplasma phagocytophilum in domestic, shelter and stray cat blood and fleas, Portugal

Cats are reservoirs of several infectious agents and potential sources of infection to humans. Examples of these are B. henselae and B. clarridgeiae, agents of cat scratch disease (CSD). The transmission occurs mainly by the scratch of contaminated cat claws. However, the possibility of direct transmission by cat fleas should not be excluded. Moreover, it is known that the presence of cat fleas (Ctenocephalides felis) is essential for the maintenance of the infection within cat populations. Cats may also be involved in the maintenance cycle of other flea-borne agents such as Rickettsia felis that cause human disease. To our knowledge no previous studies have been performed to detect the presence of Bartonella spp., R. felis and A. phagocytophilum in Portuguese cat fleas. This study also evaluated the prevalence of antibodies against Bartonella spp., Rickettsia spp. and A. phagocytophilum and the detection of Bartonella bacteraemia by PCR in cat blood.

Alternative approaches analysis for scheduling in an Extended Manufacturing Environment

Extended Manufacturing Environments (EMEs) are nowadays growing due to the increase on Distributed and Virtual Enterprises, which led to an emergent need to apply scheduling approaches accordingly. This can be achieved in several different ways, namely by putting forward new approaches or by trying to adapt existing ones. In this paper the adaptation of some existing scheduling methods is proposed for solving a two stage manufacturing scheduling problem, and an illustrative example is presented. Several approaches were analyses, namely through the use of the ANOVA and the Post Hoc Scheffes test, that demonstrated the superior performance of one of the proposed methods.

Detection of antibodies against Anaplasma phagocytophilum in Algerian mice (Mus spretus), Portugal.

The recent detection of Anaplasma phagocytophilum in Portugal stimulated further research on the agents enzootic cycle, which usually involves rodents. Thus a total 322 rodents belonging to five species, including 30 Apodemus sylvaticus (wood mouse), 65 Mus musculus (house mouse), 194 M. spretus (algerian mouse), 5 Rattus norvegicus (brown rat) and 28 R. rattus (black rat), were studied by indirect immunofluorescent assay (IFA) and/or polymerase chain reaction (PCR) for A. phagocytophilum exposure in four sampling areas of mainland and two areas of Madeira Island, Portugal. Overall, 3.6% (7/194) of M. spretus presented with IFA-positive results. Seropositive mice were detected in all three mainland sampling areas where this species was captured, with prevalence of 5.2% (5/96) and 5.0% (1/20) for the Ixodes-areas of Arrábida and Mafra, and 1.3% (1/78) for Mértola, a difference that was not statistically significant (p > 0.05). The majority of IFA-positive mice were detected in spring when considering either Arrábida alone (p = 0.026) or all M. spretus sampling areas together (p = 0.021), although the significance of this association was not evident after Bonferroni correction. Nevertheless, neither the seropositive M. spretus, nor additional samples of 10% seronegative rodents from mainland, and 16% of rodents collected in Madeira Island showed evidence of A. phagocytophilum active infections when spleen and/or lung samples were tested by PCR. Either the M. spretus results represents residual antibodies from past A. phagocytophilum infections, present infections with limited bacteremia, or cross-reactions with closely related agents deserves more investigation.

Isolation of Coxiella burnetii from the blood of a patient with positive Anaplasma phagocytophilum serological results

Division of Medical Microbiology,Department of Pathology, The Johns Hopkins University School of Medicine, Baltimore, MD, USAINTRODUCTIONHuman infections caused by bacteria in the familyAnaplasmataceae represent newly emerging tick-borne diseases. At present, Ehrlichia chaffeensis andAnaplasma phagocytophilum are the most importantmembers. The potential for human Anaplasmata-ceae exposure in Portugal justifies routine labora-tory diagnostics used by the Centro de Estudos deVectores e Doenc¸as Infecciosas, Instituto Nacional deSau´de Dr. Ricardo Jorge (CEVDI⁄INSA). Parallel E.chaffeensis and A. phagocytophilum testing, usuallybased on serology, is performed whenever clinicalsuspicion exists. Indirect immunofluorescenceassay (IFA) is the diagnostic gold-standard; how-ever, a potential for serological cross-reactivitywith other pathogens within and out of the genusexists. We present a case of acute Q fever con-firmed by unexpected isolation of Coxiella burnetiifrom an A. phagocytophilum-seropositive patient.CASE REPORTInJune2006,a39-year-old womanwasadmittedtothe Hospital Distrital de Faro, in southern Portu-gal, with 4 days of fever, chills, night sweats,severe headache, vomiting, generalised myalgia,and weight loss. On presentation, the patient alsohad non-productive cough. Her previous medicalhistory was unremarkable. She worked as a housemaid and lived in a rural area of Almancil whereshe reportedly removed ticks from her dogs priorto illness onset. The physical examination revealeda patient with no indicative neurological or cardiacsigns. A petechial rash was observed in the upperlimbs and her palms and soles were erythematous.Wheezes were audible on lung auscultation andthe liver was palpable. Bilateral hilar enlargementwith perihilar interstitial infiltrates was detectedradiographically and abdominal sonographyshowed homogeneous hepatomegaly withoutsplenomegaly. Brain CT scan was normal. Labo-ratory findings showed 3.2 · 10

Study on the impact of the NS in the performance of meta-heuristics in the TSP

Meta-heuristics have been applied for a long time to the Travelling Salesman Problem (TSP) but information is still lacking in the determination of the parameters with the best performance. This paper examines the impact of the Simulated Annealing (SA) and Discrete Artificial Bee Colony (DABC) parameters in the TSP. One special consideration of this paper is how the Neighborhood Structure (NS) interact with the other parameters and impacts the performance of the meta-heuristics. NS performance has been the topic of much research, with NS proposed for the best-known problems, which seem to imply that the NS influences the performance of meta-heuristics, more that other parameters. Moreover, a comparative analysis of distinct meta-heuristics is carried out to demonstrate a non-proportional increase in the performance of the NS.

Evaluation of the Simulated Annealing and the Discrete Artificial Bee Colony in the Weight Tardiness Problem with Taguchi Experiments Parameterization

Meta-Heuristics (MH) are the most used optimization techniques to approach Complex Combinatorial Problems (COPs). Their ability to move beyond the local optimums make them an especially attractive choice to solve complex computational problems, such as most scheduling problems. However, the knowledge of what Meta-Heuristics perform better in certain problems is based on experiments. Classic MH, as the Simulated Annealing (SA) has been deeply studied, but newer MH, as the Discrete Artificial Bee Colony (DABC) still need to be examined in more detail. In this paper DABC has been compared with SA in 30 academic benchmark instances of the weighted tardiness problem (1||Σw j T j ). Both MH parameters were fine-tuned with Taguchi Experiments. In the computational study DABC performed better and the subsequent statistical study demonstrated that DABC is more prone to find near-optimum solutions. On the other hand SA appeared to be more efficient.

A hybrid framework for supporting scheduling in extended manufacturing environments

In the current marketplace, enterprises face enormous competitive pressures. Global competition for customers that demand customized products with shorter due dates and the advancement in information technologies, marked the introduction of the Extended Enterprise. In these EMEs (Extended Manufacturing Environments), lean, virtual, networked and distributed enterprises, form MO (Meta-Organizations), which collaborate to respond to the dynamic marketplace. MO members share resources, customers and information. In this paper we present a hybrid framework based on a DKBS (Distributed Knowledge Base System), which includes information about scheduling methods for collaborative enterprises sharing their problems. A core component of this system includes an inference engine as well as two indexes, to help in the classification of the usefulness of the information about the problems and solving methods. A more structured approach for expanding the MO concept is presented, with the HO (Hyper-Organization). The manner in which MO-DSS can communicate, cooperate and share information, in the context of the HO is also detailed.

Ordered minimum completion time heuristic for unrelated parallel-machines problems

Scheduling problems in parallel machines have been deeply studied and many are too complex to be solved by exact methods. The unrelated parallel machines makespan minimization problem (Rm||Cmax) is known to be NP-hard and is usually solved using heuristics. Considering heuristics used in these problems, it is possible to identify two different approaches, those that use the execution time to allocate tasks and those that use the completion time. This paper proposes a new heuristic, OMCT (Ordered Minimum Completion Time), based on the performance limitation of the MCT (Minimum Completion Time). The computational study results demonstrate the effectiveness of the proposed heuristic.

Property-based testing for the robot operating system

The Robot Operating System (ROS) is an open source framework for the development of robotic software, in which a typical system consists of multiple processes communicating under a publisher-subscriber architecture. A great deal of development time goes into orchestration and making sure that the communication interfaces comply with the expected contracts (e.g. receiving a message leads to the publication of another message). Orchestration mistakes are only detected during runtime, stressing the importance of component and integration testing in the verification process. Property-based Testing is fitting in this context, since it is based on the specification of contracts and treats tested components as black boxes, but there is no support for it in ROS. In this paper, we present a first approach towards automatic generation of test scripts for property-based testing of various configurations of a ROS system.