Understanding the effects of Covid-19 on P2P hospitality: Comparative classification analysis for Airbnb-Barcelona

[EN] The Covid-19 pandemic has produced significant changes in tourism markets around the world. The large amount of data available on the Airbnb platform, one of the world's largest hosting services, makes it an ideal prospecting place to try to find out what the aftermath of this event has been. This paper explores the entire Airbnb housing stock in the city of Barcelona with the aim of identifying the key characteristics of the homes that have remained operational during the 2019-2021 period. We carried out this analysis by using two classification methods, the random forest and logistic regression with elastic net. The objective is to classify the houses that have remained on the platform against those that have not. Finally, we analyze the results obtained and compare both the general performance of the models and the individual information of each variable through partial dependence plots (PDP). We found a better performance of Random Forest over logistic regression, but not significant differences in the relevant variables chosen by each method. It is worth noting the importance of the geographical location, the number of amenities in the home or the price in the survival of the homes.Argente Del Castillo Martínez, JP.; Albaladejo, IP. (2022). Understanding the effects of Covid-19 on P2P hospitality: Comparative classification analysis for Airbnb-Barcelona. En 4th International Conference on Advanced Research Methods and Analytics (CARMA 2022). Editorial Universitat Politècnica de València. 221-228. https://doi.org/10.4995/CARMA2022.2022.1509122122

Reasoning about norms under uncertainty in dynamic environments

The behaviour of norm-autonomous agents is determined by their goals and the norms that are explicitly represented inside their minds. Thus, they require mechanisms for acquiring and accepting norms, determining when norms are relevant to their case, and making decisions about norm compliance. Up until now the existing proposals on norm-autonomous agents assume that agents interact within a deterministic environment that is certainly perceived. In practise, agents interact by means of sensors and actuators under uncertainty with non-deterministic and dynamic environments. Therefore, the existing proposals are unsuitable or, even, useless to be applied when agents have a physical presence in some real-world environment. In response to this problem we have developed the n-BDI architecture. In this paper, we propose a multi-context graded BDI architecture (called n-BDI) that models norm-autonomous agents able to deal with uncertainty in dynamic environments. The n-BDI architecture has been experimentally evaluated and the results are shown in this paper. © 2014 Elsevier Inc. All rights reserved

Reasoning about constitutive norms in BDI agents

Software agents can be members of different institutions along their life; they might even belong to different institutions simultaneously. For these reasons, agents need capabilities that allow them to determine the repercussion that their actions would have within the different institutions. This association between the physical word, in which agents' interactions and actions take place, and the institutional world is defined by means of constitutive norms. Currently, the problem of how agents reason about constitutive norms has been tackled from a theoretical perspective only. Thus, there is a lack of more practical proposals that allow the development of software agents capable of reasoning about constitutive norms. In this article we propose an information model, knowledge representation and an inference mechanism to enable Belief-Desire-Intention agents to reason about the consequences of their actions on the institutions and making decisions accordingly. Specifically, the information model, knowledge representation and inference mechanism proposed in this article allows agents to keep track of the institutional state given that they have a physical presence in some real-world environment. Agents have a limited and not fully believable knowledge of the physical world (i.e. they are placed in an uncertain environment). Therefore, our proposal also deals with the uncertainty of the environment. © The Author 2013. Published by Oxford University Press. All rights reserved

Reasoning about constitutive norms in BDI agents

This is a pre-copyedited, author-produced PDF of an article accepted for publication in Logic Journal of the IGPL following peer review. The definitive publisher-authenticated version: Criado Pacheco, N.; Argente Villaplana, E.; Noriega, P.; Botti Navarro, VJ. (2014). Reasoning about constitutive norms in BDI agents. Logic Journal of the IGPL. 22(1):66-93 is available online at: http://dx.doi.org/1093/jigpal/jzt035Software agents can be members of different institutions along their life; they might even belong to different institutions simultaneously. For these reasons, agents need capabilities that allow them to determine the repercussion that their actions would have within the different institutions. This association between the physical word, in which agents interactions and actions take place, and the institutional world is defined by means of constitutive norms. Currently, the problem of how agents reason about constitutive norms has been tackled from a theoretical perspective only. Thus, there is a lack of more practical proposals that allow the development of software agents capable of reasoning about constitutive norms. In this article we propose an information model, knowledge representation and an inference mechanism to enable Belief-Desire-Intention agents to reason about the consequences of their actions on the institutions and making decisions accordingly. Specifically, the information model, knowledge representation and inference mechanism proposed in this article allows agents to keep track of the institutional state given that they have a physical presence in some real-world environment. Agents have a limited and not fully believable knowledge of the physical world (i.e. they are placed in an uncertain environment). Therefore, our proposal also deals with the uncertainty of the environment.Criado Pacheco, N.; Argente Villaplana, E.; Noriega, P.; Botti Navarro, VJ. (2014). Reasoning about constitutive norms in BDI agents. Logic Journal of the IGPL. 22(1):66-93. doi:10.1093/jigpal/jzt035S6693221Baldi, P., Brunak, S., Chauvin, Y., Andersen, C. A. F., & Nielsen, H. (2000). Assessing the accuracy of prediction algorithms for classification: an overview. Bioinformatics, 16(5), 412-424. doi:10.1093/bioinformatics/16.5.412Bloch, I. (1996). Information combination operators for data fusion: a comparative review with classification. IEEE Transactions on Systems, Man, and Cybernetics - Part A: Systems and Humans, 26(1), 52-67. doi:10.1109/3468.477860Casali, A., Godo, L., & Sierra, C. (2011). A graded BDI agent model to represent and reason about preferences. Artificial Intelligence, 175(7-8), 1468-1478. doi:10.1016/j.artint.2010.12.006Criado, N., Julián, V., Botti, V., & Argente, E. (2010). A Norm-Based Organization Management System. Lecture Notes in Computer Science, 19-35. doi:10.1007/978-3-642-14962-7_2Governatori, G., & Rotolo, A. (2008). BIO logical agents: Norms, beliefs, intentions in defeasible logic. Autonomous Agents and Multi-Agent Systems, 17(1), 36-69. doi:10.1007/s10458-008-9030-4Grossi, D., Aldewereld, H., Vázquez-Salceda, J., & Dignum, F. (2006). Ontological aspects of the implementation of norms in agent-based electronic institutions. Computational & Mathematical Organization Theory, 12(2-3), 251-275. doi:10.1007/s10588-006-9546-6Hübner, J. F., Boissier, O., Kitio, R., & Ricci, A. (2009). Instrumenting multi-agent organisations with organisational artifacts and agents. Autonomous Agents and Multi-Agent Systems, 20(3), 369-400. doi:10.1007/s10458-009-9084-yJONES, A. J. I., & SERGOT, M. (1996). A Formal Characterisation of Institutionalised Power. Logic Journal of IGPL, 4(3), 427-443. doi:10.1093/jigpal/4.3.427Rawls, J. (1955). Two Concepts of Rules. The Philosophical Review, 64(1), 3. doi:10.2307/2182230Da Silva, V. T. (2008). From the specification to the implementation of norms: an automatic approach to generate rules from norms to govern the behavior of agents. Autonomous Agents and Multi-Agent Systems, 17(1), 113-155. doi:10.1007/s10458-008-9039-

Reasoning about norms under uncertainty in dynamic environments

The behaviour of norm-autonomous agents is determined by their goals and the norms that are explicitly represented inside their minds. Thus, they require mechanisms for acquiring and accepting norms, determining when norms are relevant to their case, and making decisions about norm compliance. Up un- til now the existing proposals on norm-autonomous agents assume that agents interact within a deterministic environment that is certainly perceived. In prac- tice, agents interact by means of sensors and actuators under uncertainty with non-deterministic and dynamic environments. Therefore, the existing propos- als are unsuitable or, even, useless to be applied when agents have a physical presence in some real-world environment. In response to this problem we have developed the n-BDI architecture. In this paper, we propose a multi -context graded BDI architecture (called n-BDI) that models norm-autonomous agents able to deal with uncertainty in dynamic environments. The n-BDI architecture has been experimentally evaluated and the results are shown in this paper.This paper was partially funded by the Spanish government under Grant CONSOLIDER-INGENIO 2010 CSD2007-00022 and the Valencian government under Project PROMETEOH/2013/019.Criado Pacheco, N.; Argente, E.; Noriega, P.; Botti Navarro, VJ. (2014). Reasoning about norms under uncertainty in dynamic environments. International Journal of Approximate Reasoning. 55(9):2049-2070. https://doi.org/10.1016/j.ijar.2014.02.004S2049207055

Cardiometabolic and Cardiovascular Complications of Obesity in Children

The rise in obesity in both children and adults has made obesity one of the biggest public health problems of this century. Obesity along with other factors such as hypertension, insulin resistance, dyslipidemia and diabetes mellitus are risk factors for the development of cardiovascular diseases. Overweight and/or obesity during childhood and its maintenance until adult life has been associated with early stages of cardiovascular disease. For this reason, the aim of this study is to revise the state of the art of cardiometabolic and cardiovascular complications related with overweight and/or obesity in children and adolescents. The first consequence of weight gain is an increase in adipose tissue, with different distribution depending on the sex. The excess of fat mass entails dysfunction of adipose tissue with an altered secretion of adipokines and instauration of a proinflammatory environment, which may derive in metabolic syndrome condition. The increase of adipose tissue along with an increase in sympathetic nervous system, triggers an increased left ventricular mass and with a reduced diastolic function. Therefore, obesity should be prevented from the early stages of life, in order to avoid obesity itself and the metabolic disturbances that could undermine quality of life further on

Correlated response to selection for litter size environmental variability in rabbits' resilience

[EN] Resilience is the ability of an animal to return soon to its initial productivity after facing diverse environmental challenges. This trait is directly related to animal welfare and it plays a key role in fluctuations of livestock productivity. A divergent selection experiment for environmental variance of litter size has been performed successfully in rabbits over ten generations. The objective of this study was to analyse resilience indicators of stress and disease in the divergent lines of this experiment. The high line showed a lower survival rate at birth than the low line (-4.1%). After correcting by litter size, the difference was -3.2%. Involuntary culling rate was higher in the high than in the low line (+12.4%). Before vaccination against viral haemorrhagic disease or myxomatosis, concentration of lymphocytes, C-reactive protein (CRP), complement C3, serum bilirubin, triglycerides and cholesterol were higher in the high line than in the low line (difference between lines +4.5%, +5.6 mu g/ml, +4.6 mg/ml, +7.9 mmol/l, +0.3 mmol/l and +0.4 mmol/l). Immunological and biochemical responses to the two vaccines were similar. After vaccination, the percentage of lymphocytes and CRP concentration were higher in the low line than in the high one (difference between lines +4.0% and +13.1 mu g/ml). The low line also showed a higher increment in bilirubin and triglycerides than the high line (+14.2 v. +8.7 mmol/l for bilirubin and +0.11 v. +0.01 mmol/l for triglycerides); these results would agree with the protective role of bilirubin and triglycerides against the larger inflammatory response found in this line. In relation to stress, the high line had higher basal concentration of cortisol than the low line (+0.2ng/ml); the difference between lines increased more than threefold after the injection of ACTH 1 to 24, the increase being greater in the high line (+0.9 ng/ml) than in the low line (+0.4 ng/ml). Selection for divergent environmental variability of litter size leads to dams with different culling rate for reproductive causes and different kits' neonatal survival. These associations suggest that the observed fitness differences are related to differences in the inflammatory response and the corticotrope response to stress, which are two important components of physiological adaptation to environmental aggressions.This study is supported by the Spanish Ministry of Economy and Competitiveness (MINECO) with the Projects AGL2014-55921, C2-1-P and C2-2-P, and AGL2017-86083, C2-1-P and C2-2-P.Argente, M.; Garcia, M.; Zbynovska, K.; Petruska, P.; Capcarova, M.; Blasco Mateu, A. (2019). Correlated response to selection for litter size environmental variability in rabbits' resilience. Animal. 13(10):2348-2355. https://doi.org/10.1017/S1751731119000302S234823551310Glaser, R., & Kiecolt-Glaser, J. K. (2005). Stress-induced immune dysfunction: implications for health. Nature Reviews Immunology, 5(3), 243-251. doi:10.1038/nri1571Markanday, A. (2015). Acute Phase Reactants in Infections: Evidence-Based Review and a Guide for Clinicians. Open Forum Infectious Diseases, 2(3). doi:10.1093/ofid/ofv098Rauw, W. ., Kanis, E., Noordhuizen-Stassen, E. ., & Grommers, F. . (1998). Undesirable side effects of selection for high production efficiency in farm animals: a review. Livestock Production Science, 56(1), 15-33. doi:10.1016/s0301-6226(98)00147-xPiles, M., García, M. L., Rafel, O., Ramon, J., & Baselga, M. (2006). Genetics of litter size in three maternal lines of rabbits: Repeatability versus multiple-trait models. Journal of Animal Science, 84(9), 2309-2315. doi:10.2527/jas.2005-622Guelfi, G., Zerani, M., Brecchia, G., Parillo, F., Dall’Aglio, C., Maranesi, M., & Boiti, C. (2011). Direct actions of ACTH on ovarian function of pseudopregnant rabbits. Molecular and Cellular Endocrinology, 339(1-2), 63-71. doi:10.1016/j.mce.2011.03.017García ML , Blasco A , García ME and Argente MJ 2018. Body condition and energy mobilisation in rabbits selected for litter size variability. Animal, 1–6, https://doi.org/10.1017/S1751731118002203, Published online by Cambridge University Press 28 August 2018.Furze, R. C., & Rankin, S. M. (2008). Neutrophil mobilization and clearance in the bone marrow. Immunology, 125(3), 281-288. doi:10.1111/j.1365-2567.2008.02950.xMcDade, T. W., Borja, J. B., Kuzawa, C. W., Perez, T. L. L., & Adair, L. S. (2015). C-reactive protein response to influenza vaccination as a model of mild inflammatory stimulation in the Philippines. Vaccine, 33(17), 2004-2008. doi:10.1016/j.vaccine.2015.03.019Blasco, A. (2017). Bayesian Data Analysis for Animal Scientists. doi:10.1007/978-3-319-54274-4Castellini, C., Dal Bosco, A., Arias-Álvarez, M., Lorenzo, P. L., Cardinali, R., & Rebollar, P. G. (2010). The main factors affecting the reproductive performance of rabbit does: A review. Animal Reproduction Science, 122(3-4), 174-182. doi:10.1016/j.anireprosci.2010.10.003Rosa Neto, N. S., & Carvalho, J. F. de. (2009). O uso de provas de atividade inflamatória em reumatologia. Revista Brasileira de Reumatologia, 49(4), 413-430. doi:10.1590/s0482-50042009000400008Argente, M. J., Calle, E. W., García, M. L., & Blasco, A. (2017). Correlated response in litter size components in rabbits selected for litter size variability. Journal of Animal Breeding and Genetics, 134(6), 505-511. doi:10.1111/jbg.12283Mirkena, T., Duguma, G., Haile, A., Tibbo, M., Okeyo, A. M., Wurzinger, M., & Sölkner, J. (2010). Genetics of adaptation in domestic farm animals: A review. Livestock Science, 132(1-3), 1-12. doi:10.1016/j.livsci.2010.05.003García, M. L., Blasco, A., & Argente, M. J. (2016). Embryologic changes in rabbit lines selected for litter size variability. Theriogenology, 86(5), 1247-1250. doi:10.1016/j.theriogenology.2016.04.065Feingold KR and Grunfeld C 2015. The effect of inflammation and infection on lipids and lipoproteins. In: De Groot LJ, Chrousos G, Dungan K, Feingold KR, Grossman A, Hershman JM, Koch C, Korbonits M, McLachlan R, New M, Purnell J, Rebar R, Singer F and Vinik A. Endotext, South Dartmouth, MA, USA. Retrieved on 7 June 2018 from https://www.ncbi.nlm.nih.gov/books/NBK326741/.Minemura, M. (2014). Liver involvement in systemic infection. World Journal of Hepatology, 6(9), 632. doi:10.4254/wjh.v6.i9.632Knap, P. W. (2005). Breeding robust pigs. Australian Journal of Experimental Agriculture, 45(8), 763. doi:10.1071/ea05041Barcia, A. M., & Harris, H. W. (2005). Triglyceride-Rich Lipoproteins as Agents of Innate Immunity. Clinical Infectious Diseases, 41(Supplement_7), S498-S503. doi:10.1086/432005Webster, J. I., Tonelli, L., & Sternberg, E. M. (2002). NEUROENDOCRINEREGULATION OFIMMUNITY. Annual Review of Immunology, 20(1), 125-163. doi:10.1146/annurev.immunol.20.082401.104914Fortun-Lamothe, L. (2006). Energy balance and reproductive performance in rabbit does. Animal Reproduction Science, 93(1-2), 1-15. doi:10.1016/j.anireprosci.2005.06.009Cabezas, S., Blas, J., Marchant, T. A., & Moreno, S. (2007). Physiological stress levels predict survival probabilities in wild rabbits. Hormones and Behavior, 51(3), 313-320. doi:10.1016/j.yhbeh.2006.11.004De Nardo, D., Labzin, L. I., Kono, H., Seki, R., Schmidt, S. V., Beyer, M., … Latz, E. (2013). High-density lipoprotein mediates anti-inflammatory reprogramming of macrophages via the transcriptional regulator ATF3. Nature Immunology, 15(2), 152-160. doi:10.1038/ni.2784BURKUŠ, J., KAČMAROVÁ, M., KUBANDOVÁ, J., KOKOŠOVÁ, N., FABIANOVÁ, K., FABIAN, D., … ČIKOŠ, Š. (2015). Stress exposure during the preimplantation period affects blastocyst lineages and offspring development. Journal of Reproduction and Development, 61(4), 325-331. doi:10.1262/jrd.2015-012Posthouwer, D., Voorbij, H. A. M., Grobbee, D. E., Numans, M. E., & van der Bom, J. G. (2004). Influenza and pneumococcal vaccination as a model to assess C-reactive protein response to mild inflammation. Vaccine, 23(3), 362-365. doi:10.1016/j.vaccine.2004.05.035Ibáñez-Escriche, N., Sorensen, D., Waagepetersen, R., & Blasco, A. (2008). Selection for Environmental Variation: A Statistical Analysis and Power Calculations to Detect Response. Genetics, 180(4), 2209-2226. doi:10.1534/genetics.108.091678Colditz, I. G., & Hine, B. C. (2016). Resilience in farm animals: biology, management, breeding and implications for animal welfare. Animal Production Science, 56(12), 1961. doi:10.1071/an15297Blasco, A., Martínez-Álvaro, M., García, M.-L., Ibáñez-Escriche, N., & Argente, M.-J. (2017). Selection for environmental variance of litter size in rabbits. Genetics Selection Evolution, 49(1). doi:10.1186/s12711-017-0323-4Argente MJ , Santacreu MA , Climen A and Blasco A 2000. Genetic correlations between litter size and uterine capacity. In Proceeding of the 8th World Rabbit Congress, 4–7 July 2000, Valencia, Spain, pp. 333–338.Janssens, C. J., Helmond, F. A., & Wiegant, V. M. (1995). Chronic stress and pituitary–adrenocortical responses to corticotropin-releasing hormone and vasopressin in female pigs. European Journal of Endocrinology, 132(4), 479-486. doi:10.1530/eje.0.132047

Designing normative open virtual enterprises

This is an Accepted Manuscript of an article published by Taylor & Francis Group in Enterprise Information Systems on 23/03/2016, available online: http://www.tandfonline.com/10.1080/17517575.2015.1036927.[EN] There is an increasing interest on developing virtual enterprises in order to deal with the globalisation of the economy, the rapid growth of information technologies and the increase of competitiveness. In this paper we deal with the development of normative open virtual enterprises (NOVEs). They are systems with a global objective that are composed of a set of heterogeneous entities and enterprises that exchange services following a specific normative context. In order to analyse and design systems of this kind the multi-agent paradigm seems suitable because it offers a specific solution for supporting the social and contractual relationships between enterprises and for formalising their business processes. This paper presents how the Regulated Open Multiagent systems (ROMAS) methodology, an agent-oriented software methodology, can be used to analyse and design NOVEs. ROMAS offers a complete development process that allows identifying and formalising of the structure of NOVEs, their normative context and the interactions among their members. The use of ROMAS is exemplified by means of a case study that represents an automotive supply chain.This work was partially supported by the projects [PROMETEOII/2013/019], [TIN2012-36586-C03-01], [FP7-29493], [TIN2011-27652-C03-00] and [CSD2007-00022], and the CASES project within the 7th European Community Framework Programme [grant agreement number 294931].Garcia Marques, ME.; Giret Boggino, AS.; Botti Navarro, VJ. (2016). Designing normative open virtual enterprises. Enterprise Information Systems. 10(3):303-324. https://doi.org/10.1080/17517575.2015.1036927S303324103Cardoso, H. L., Urbano, J., Brandão, P., Rocha, A. P., & Oliveira, E. (2012). ANTE: Agreement Negotiation in Normative and Trust-Enabled Environments. Advances on Practical Applications of Agents and Multi-Agent Systems, 261-264. doi:10.1007/978-3-642-28786-2_33Chu, X. N., Tso, S. K., Zhang, W. J., & Li, Q. (2002). Partnership Synthesis for Virtual Enterprises. The International Journal of Advanced Manufacturing Technology, 19(5), 384-391. doi:10.1007/s001700200028Davidsson, P., & Jacobsson, A. (s. f.). Towards Norm-Governed Behavior in Virtual Enterprises. Studies in Computational Intelligence, 35-55. doi:10.1007/978-3-540-88071-4_3DeLoach, S. A., & Ojeda, J. C. G. (2010). O-MaSE: a customisable approach to designing and building complex, adaptive multi-agent systems. International Journal of Agent-Oriented Software Engineering, 4(3), 244. doi:10.1504/ijaose.2010.036984DI MARZO SERUGENDO, G., GLEIZES, M.-P., & KARAGEORGOS, A. (2005). Self-organization in multi-agent systems. The Knowledge Engineering Review, 20(2), 165-189. doi:10.1017/s0269888905000494Dignum, V. 2003. “A Model for Organizational Interaction: Based on Agents, Founded in Logic.” PhD diss., Utrecht University.Dignum, V., and F. Dignum. 2006.A Landscape of Agent Systems for the Real World. Technical Report 44-CS-2006-061. Utrecht: Institute of Information and Computing Sciences, Utrecht University.Dignum, V., Meyer, J.-J. C., Dignum, F., & Weigand, H. (2003). Formal Specification of Interaction in Agent Societies. Lecture Notes in Computer Science, 37-52. doi:10.1007/978-3-540-45133-4_4Garcia, E. 2013. “Engineering Regulated Open Multiagent Systems.” PhD diss., Universitat Politecnica de Valencia.Garcia, E., Giret, A., & Botti, V. (s. f.). Software Engineering for Service-Oriented MAS. Lecture Notes in Computer Science, 86-100. doi:10.1007/978-3-540-85834-8_9Garcia, E., Giret, A., & Botti, V. (2013). A Model-Driven CASE tool for developing and verifying regulated open MAS. Science of Computer Programming, 78(6), 695-704. doi:10.1016/j.scico.2011.10.009Garcia, E., Giret, A., & Botti, V. (2011). Evaluating software engineering techniques for developing complex systems with multiagent approaches. Information and Software Technology, 53(5), 494-506. doi:10.1016/j.infsof.2010.12.012Garcia, E., Giret, A., & Botti, V. (2011). Regulated Open Multi-Agent Systems Based on Contracts. Information Systems Development, 243-255. doi:10.1007/978-1-4419-9790-6_20Garcia, E., Giret, A., & Botti, V. (2014). ROMAS Methodology. Handbook on Agent-Oriented Design Processes, 331-369. doi:10.1007/978-3-642-39975-6_11Hollander, C. D., & Wu, A. S. (2011). The Current State of Normative Agent-Based Systems. Journal of Artificial Societies and Social Simulation, 14(2). doi:10.18564/jasss.1750HORLING, B., & LESSER, V. (2004). A survey of multi-agent organizational paradigms. The Knowledge Engineering Review, 19(4), 281-316. doi:10.1017/s0269888905000317Julian, V., Rebollo, M., Argente, E., Botti, V., Carrascosa, C., & Giret, A. (2009). Using THOMAS for Service Oriented Open MAS. Lecture Notes in Computer Science, 56-70. doi:10.1007/978-3-642-10739-9_5Luck, M., Barakat, L., Keppens, J., Mahmoud, S., Miles, S., Oren, N., … Taweel, A. (2011). Flexible Behaviour Regulation in Agent Based Systems. Lecture Notes in Computer Science, 99-113. doi:10.1007/978-3-642-22427-0_8Meneguzzi, F., Modgil, S., Oren, N., Miles, S., Luck, M., & Faci, N. (2012). Applying electronic contracting to the aerospace aftercare domain. Engineering Applications of Artificial Intelligence, 25(7), 1471-1487. doi:10.1016/j.engappai.2012.06.004Presley, A., Sarkis, J., Barnett, W., & Liles, D. (2001). International Journal of Flexible Manufacturing Systems, 13(2), 145-162. doi:10.1023/a:1011131417956Saeki, M., & Kaiya, H. (2008). Supporting the Elicitation of Requirements Compliant with Regulations. Active Flow and Combustion Control 2018, 228-242. doi:10.1007/978-3-540-69534-9_18Such, J. M., García-Fornes, A., Espinosa, A., & Bellver, J. (2013). Magentix2: A privacy-enhancing Agent Platform. Engineering Applications of Artificial Intelligence, 26(1), 96-109. doi:10.1016/j.engappai.2012.06.009Telang, P. R., & Singh, M. P. (2009). Enhancing Tropos with Commitments. Lecture Notes in Computer Science, 417-435. doi:10.1007/978-3-642-02463-4_22Wooldridgey, M., & Ciancarini, P. (2001). Agent-Oriented Software Engineering: The State of the Art. Lecture Notes in Computer Science, 1-28. doi:10.1007/3-540-44564-1_

Building quests for online games with virtual institutions

Abstract. This document describes how to re-purpose an existing agent technology called Virtual Institutions as a mechanism to define new "quest" elements in Massively Multiplayer Online Games based on MultiAgent Systems. Quests are a very important part of most Massive Online Games as they wield to flow and narrative of the game in a linear or nonlinear manner

Body composition by dual X-ray absorptiometry in Mexican schoolchildren with or without obesity

Objective: Apply dual X-ray absorptiometry (DXA) to determine the amount of fat mass, lean mass, and bone mineral density in Mexican schoolchildren with and without obesity. Material and methods: We performed an observational, analytical, comparative, cross-sectional study of 80 Mexican schoolchildren who attended the Nutrition Clinic of the Pediatric Medical Center in Monterrey, Mexico during the period of January to April 2005. Body mass index (BMI) was determined to classify the participants according to the growth charts of the Centers for Disease Control and Prevention. Two groups of 40 children each (with and without obesity) were formed and DXA was carried out on each individual. Cronbach’s Alpha was used to determine instrument reliability and the Kolmogorov-Smirnov test was used to test the normality of numerical variables. Means were compared using Student´s t test. Results: Statistically signiicant differences were found in fat mass (p≤0.001) and lean mass (p≤0.001), but not in bone mineral content (p=0.051) between both groups. Conclusions: Differences exist in fat mass and lean mass in both groups, but not in bone mineral content between both groups. A signiicant positive correlation was found between fat mass, determined by DXA, and BMI in schoolchildren with and without obesit