Modelling of Multi-Agent Systems: Experiences with Membrane Computing and Future Challenges

Formal modelling of Multi-Agent Systems (MAS) is a challenging task due to high complexity, interaction, parallelism and continuous change of roles and organisation between agents. In this paper we record our research experience on formal modelling of MAS. We review our research throughout the last decade, by describing the problems we have encountered and the decisions we have made towards resolving them and providing solutions. Much of this work involved membrane computing and classes of P Systems, such as Tissue and Population P Systems, targeted to the modelling of MAS whose dynamic structure is a prominent characteristic. More particularly, social insects (such as colonies of ants, bees, etc.), biology inspired swarms and systems with emergent behaviour are indicative examples for which we developed formal MAS models. Here, we aim to review our work and disseminate our findings to fellow researchers who might face similar challenges and, furthermore, to discuss important issues for advancing research on the application of membrane computing in MAS modelling.Comment: In Proceedings AMCA-POP 2010, arXiv:1008.314

M.: OPERASCC: An instance of a formal framework for MAS modelling based on Population P Systems

Swarm-based systems are biology-inspired systems which possess characteristics of multi-agent systems (MAS) with the most prominent ones being the local control over the decisions taken and their highly dynamic structure which continuously changes. This class of MAS is of a particular interest because it exhibits emergent behaviour through self-organisation and finds itself applicable to a wide range of domains. In this paper, we present OPERAS, an open formal framework that facilitates modelling of MAS, we describe how a particular instance of this framework, namely OPERASCC, could employ existing biological computation systems, such as Population P Systems, and demonstrate how the resulting method can be used to formally model a swarm-based system of autonomous spacecrafts.

Teaching AI and IA into a non-science graduate programme

As part of designing a new Master?s programme entitled Technology, Innovation and Entrepreneurship there was an apparent need to include a unit involving the use of innovative technologies for the development of innovative products and services. The authors aim was therefore to introduce students to Artificial Intelligence and Intelligent Agents using, however, different from ?mainstream? practices since the programme is addressed to students from varying, not necessarily Computer Science related, backgrounds. In this work they report their approach and experience from the entire process -from designing the unit, taking into consideration some inherent restrictions such as coordination of teachers and short duration of the course, to delivering it to a diverse audience that requires different didactic methods to be employed. Their primary aim is to disseminate their ideas and report good practice to fellow educators that may face similar situations or wish to employ any of our techniques

From Alkestis to Archidike: Thessalian Attitudes to Death and the Afterlife

The aim of this chapter is to offer a regional perspective on the issue of Underworld journeys in Antiquity by tracing Thessalian attitudes to Hades from the Classical to the Hellenistic period. What do we know of the beliefs regarding the Underworld in Thessaly, a land where one of the most famous and successful katabaseis occurred? Our starting point will be the most famous Thessalian ‘round trip’ to Hades, that of Alkestis, portrayed through Athenian eyes in Euripides’ tragedy and Plato. This will allow us to discuss eschatological beliefs reflected in fifth-century BCE Athenian literary works and address some of the stereotypes about Thessaly, as both are linked to the questions under discussion. We will then turn to Thessaly itself and examine a variety of relevant evidence pertaining to cults of deities linked with passages and human destiny, the gold lamellae from Pherai and Pharsalos, funerary epigrams from the region echoing themes attested in the lamellae or revealing a concern with or a belief in the possibility of a blessed afterlife or for a ‘round trip to the Underworld’ and last but not least, the evidence from contemporary Thessalian necropoleis. As will be seen, the Thessalian evidence, although of a complex and often disparate nature, is suggestive of a heightened interest in the safe journey to the Underworld or a blessed afterlife

Bioaugmentation of thiabendazole-contaminated soils from a wastewater disposal site: Factors driving the efficacy of this strategy and the diversity of the indigenous soil bacterial community

The application of the fungicide thiabendazole (TBZ) in fruit packaging plants (FPP) results in the production of effluents which are often disposed in adjacent field sites. These require remediation to prevent further environmental dispersal of TBZ. We assessed the bioaugmentation potential of a newly isolated TBZ-degrading bacterial consortium in a naturally contaminated soil (NCS) exhibiting a natural gradient of TBZ levels (12000, 400, 250 and 12 mg kg−1). The effect of aging on bioaugmentation efficacy was comparatively tested in a soil with similar physicochemical properties and soil microbiota, which was artificially, contaminated with the same TBZ levels (ACS). The impact of bioaugmentation and TBZ on the bacterial diversity in the NCS was explored via amplicon sequencing. Bioaugmentation effectively removed TBZ from both soils at levels up to 400 mg kg−1 but failed at the highest contamination level (12000 mg kg−1). Dissipation of TBZ in bioaugmented samples showed a concentration-dependent pattern, while aging of TBZ had a slight effect on bioaugmentation efficiency. Bioaugmentation had no impact on the soil bacterial diversity, in contrast to TBZ contamination. Soils from the hotspots of TBZ contamination (12000 mg kg−1) showed a drastically lower α-diversity driven by the dominance of β- and γ-proteobacteria at the expense of all other bacterial phyla, especially Actinobacteria. Overall, bioaugmentation with specialized microbial inocula could be an effective solution for the recovery of disposal sites contaminated with persistent chemicals like TBZ. Bioaugmentation with a specialized bacterial consortium was effective in the remediation of soils naturally contaminated with the persistent fungicide thiabendazole, and did not affect the soil bacterial diversity, the latter being heavily affected by high fungicide levels. © 2017 Elsevier Lt

Association of anti-CCP positivity and carriage of TNFRII susceptibility variant with anti-TNF-α response in rheumatoid arthritis

Objective: To investigate the possible influence of tumour necrosis factoralpha (TNF), TNF receptor I (TNFRI) and TNF receptor II (TNFRII) gene polymorphisms on anti-TNF treatment responsiveness, stratified by autoantibody status. Methods: A Greek multi-centre collaboration was established to recruit a cohort of patients (n=100) with active RA treated with anti-TNF drugs. TNF g.-238G>A (rs361525), g.-308G>A (rs1800629), g.-857C>T (rs1799724), TNFRI c.36A>G (rs4149584) and TNFRII c.676T>G (rs1061622) polymorphisms were genotyped by PCRRFLP assays. Serum RF and anti-CCP antibody status were determined using commercially available kits. Single-SNP, haplotype and stratification by autoantibody status analyses were performed in predicting response to treatment by 6 months, defined as the absolute change in DAS28. Results: 31 patients (31%) were defined as non-responders due to failure to fulfill the DAS28 criteria. 79% and 66% were RF and anti-CCP positive, respectively. None of the genotyped SNPs was alone associated with responsiveness to drug treatment. However, after stratification by autoantibody status, carriage of TNFRII c.676G allele was associated with poorer response to drug treatment in anti-CCP positive patients (p=0.03), after 6 months of anti-TNF therapy. Conclusion: In concordance with previous studies, genetic polymorphisms alone cannot be used to safely predict clinical response to anti-TNF therapy however the combination of genetic factors and autoantibody status warrants further investigation in larger independent cohorts. © Clinical and Experimental Rheumatology 2011

Association of anti-CCP positivity and carriage of TNFRII susceptibility variant with anti-TNF-alpha response in rheumatoid arthritis

Objective. To investigate the possible influence of tumour necrosis factor-alpha (TNF), TNF receptor I (TNFRI) and TNF receptor II (TNFRII) gene polymorphisms on anti-TNF treatment responsiveness, stratified by autoantibody status. Methods. A Greek multi-centre collaboration was established to recruit a cohort of patients (n=100) with active RA treated with anti-TNF drugs. TNF g.-238G>A (rs361525), g.-308G>A (rs1800629), g.-857C>T (rsl 799724), TNFRI c.36A>G (rs4149584) and TNFRII c.676T>G (rs1061622) polymorphisms were genotyped by PCR-RFLP assays. Serum RF and anti-CCP antibody status were determined using commercially available kits. Single-SNP, haplotype and stratification autoantibody status analyses were performed in predicting response to treatment by 6 months, defined as the absolute change in DAS28. Results. 31 patients (31%) were defined as non-responders due to failure to fulfill the DAS28 criteria. 79% and 66% were RF and anti-CCP positive, respectively. None of the genotyped SNPs was alone associated with responsiveness to drug treatment. However, after stratification by autoantibody status, carriage of TNFRII c.676G allele was associated with poorer response to drug treatment in anti-CCP positive patients (p=0.03), after 6 months of anti-TNF therapy. Conclusion. In concordance with previous studies, genetic polymorphisms alone cannot be used to safely predict clinical response to anti-TNF therapy however the combination of genetic factors and autoantibody status warrants further investigation in larger independent cohorts

Utilization of Systemic Chemotherapy in Advanced Urothelial Cancer: A Retrospective Collaborative Study by the Hellenic Genitourinary Cancer Group (HGUCG)

Background Advanced urothelial cancer (AUCa) is associated with poor long-term survival. Two major concerns are related to nonexposure to cisplatin-based chemotherapy and poor outcome after relapse. Our purpose was to record patterns of practice in AUCa in Greece, focusing on first-line treatment and management of relapsed disease. Methods Patients with AUCa treated from 2011 to 2013 were included in the analysis. Fitness for cisplatin was assessed by recently established criteria. Results Of 327 patients treated with first-line chemotherapy, 179 (55%) did not receive cisplatin. Criteria for unfitness for cisplatin were: Eastern Cooperative Oncology Group (ECOG) performance status (PS) ≥ 2, 21%; creatinine clearance ≤ 60 mL/min, 55%; hearing impairment, 8%; neuropathy, 1%; and cardiac failure, 5%. Forty-six patients (27%) did not fulfill any criterion for unfitness for cisplatin. The main reasons for these deviations were comorbidities (28%) and advanced age (32%). Seventy-four (68%) of 109 patients who experienced a relapse received second-line chemotherapy. The most frequent reason for not offering second-line chemotherapy was poor PS or limited life expectancy (66%). Conclusion In line with international data, approximately 50% of Greek patients with AUCa do not receive cisplatin-based chemotherapy, although 27% of them were suitable for such treatment. In addition, about one third of patients with relapse did not receive second-line chemotherapy because of poor PS or short life expectancy. Enforcing criteria for fitness for cisplatin and earlier diagnosis of relapse represent 2 targets for improvement in current treatment practice for AUCa. © 2016 Elsevier Inc