Migrating learning management systems: A case of a large public university

In the past 20 years, institutions of higher education have made major investments in Learning Management Systems (LMSs). As institutions have integrated the LMS into campus culture, the potential of migrating to not only an upgraded version of the LMS, but also an entirely different LMS, has become a reality. This qualitative research study examines the perspectives of five stakeholders involved with the migration of an LMS at a major research institution in the southeastern United States. Using Lewin’s (1947) Change Management Model and Enterprise Resource Planning (ERP) Model as analogies, this research seeks to understand the role and responsibilities of the various stakeholders, their decision-making, and the implications of the decisions on the migration process. Using Glaser and Strauss’s (1967) constant comparative method and Charmaz’s (2006) work related to grounded theory, four major categories emerged from our data: time as a catalyst for change, power of communication, compatibility of technologies, and faith in the system. The categories contribute to a preliminary model that may assist other institutions as they consider whether to migrate LMSs

Implementing MAS agreement processes based on consensus networks

[EN] Consensus is a negotiation process where agents need to agree upon certain quantities of interest. The theoretical framework for solving consensus problems in dynamic networks of agents was formally introduced by Olfati-Saber and Murray, and is based on algebraic graph theory, matrix theory and control theory. Consensus problems are usually simulated using mathematical frameworks. However, implementation using multi-agent system platforms is a very difficult task due to problems such as synchronization, distributed finalization, and monitorization among others. The aim of this paper is to propose a protocol for the consensus agreement process in MAS in order to check the correctness of the algorithm and validate the protocol. © Springer International Publishing Switzerland 2013.This work is supported by ww and PROMETEO/2008/051 projects of the Spanish government, CONSOLIDER-INGENIO 2010 under grant CSD2007-00022, TIN2012-36586-C03-01 and PAID-06-11-2084.Palomares Chust, A.; Carrascosa Casamayor, C.; Rebollo Pedruelo, M.; Gómez, Y. (2013). Implementing MAS agreement processes based on consensus networks. Distributed Computing and Artificial Intelligence. 217:553-560. https://doi.org/10.1007/978-3-319-00551-5_66S553560217Argente, E.: et al: An Abstract Architecture for Virtual Organizations: The THOMAS approach. Knowledge and Information Systems 29(2), 379–403 (2011)Búrdalo, L.: et al: TRAMMAS: A tracing model for multiagent systems. Eng. Appl. Artif. Intel. 24(7), 1110–1119 (2011)Fogués, R.L., et al.: Towards Dynamic Agent Interaction Support in Open Multiagent Systems. In: Proc. of the 13th CCIA, vol. 220, pp. 89–98. IOS Press (2010)Luck, M., et al.: Agent technology: Computing as interaction (a roadmap for agent based computing). Eng. Appl. Artif. Intel. (2005)Mailler, R., Lesser, V.: Solving distributed constraint optimization problems using cooperative mediation. In: AAMAS 2004, pp. 438–445 (2004)Olfati-Saber, R., Fax, J.A., Murray, R.M.: Consensus and cooperation in networked multi-agent systems. Proceedings of the IEEE 95(1), 215–233 (2007)Pujol-Gonzalez, M.: Multi-agent coordination: Dcops and beyond. In: Proc. of IJCAI, pp. 2838–2839 (2011)Such, J.: et al: Magentix2: A privacy-enhancing agent platform. Eng. Appl. Artif. Intel. 26(1), 96–109 (2013)Vinyals, M., et al.: Constructing a unifying theory of dynamic programming dcop algorithms via the generalized distributive law. Autonomous Agents and Multi-Agent Systems 22, 439–464 (2011

The training-induced changes on automatism, conduction and myocardial refractoriness are not mediated by parasympathetic postganglionic neurons activity

The purpose of this study is to test the role that parasympathetic postganglionic neurons could play on the adaptive electrophysiological changes produced by physical training on intrinsic myocardial automatism, conduction and refractoriness. Trained rabbits were submitted to aphysical training protocol on treadmill during 6 weeks. The electrophysiological study was performed in an isolated heart preparation. The investigated myocardial properties were: (a) sinus automatism, (b) atrioventricular and ventriculoatrial conduction, (c) atrial, conduction system and ventricular refractoriness. The parameters to study the refractoriness were obtained by means of extrastimulus test at four diVerent pacing cycle lengths (10% shorter than spontaneous sinus cycle length, 250, 200 and 150 ms) and (d) mean dominant frequency (DF) of the induced ventricular Wbrillation (VF), using a spectral method. The electrophysiological protocol was performed before and during continuous atropine administration (1 ¿M), in order to block cholinergic receptors. Cholinergic receptor blockade did not modify either the increase in sinus cycle length, atrioventricular conduction and refractoriness (left ventricular and atrioventricular conduction system functional refractory periods) or the decrease of DF of VF. These Wndings reveal that the myocardial electrophysiological modiWcations produced by physical training are not mediated by intrinsic cardiac parasympathetic activity.The authors thank Carmen Rams, Ana Diaz, Pilar Navarro and Cesar Avellaneda for their excellent technical assistance. This work has been supported by grants from the Spanish Ministry of Education and Science (DEP2007-73234-C03-01) and Generalitat Valenciana (PROMETEO 2010/093). M Zarzoso was supported by a research scholarship from Generalitat Valenciana (BFPI/2008/003).Zarzoso Muñoz, M.; Such Miquel, L.; Parra Giraldo, G.; Brines Ferrando, L.; Such, L.; Chorro, F.; Guerrero, J.... (2012). The training-induced changes on automatism, conduction and myocardial refractoriness are not mediated by parasympathetic postganglionic neurons activity. European Journal of Applied Physiology. 112(6):2185-2193. https://doi.org/10.1007/s00421-011-2189-4S218521931126Armour JA, Hopkins DA (1990a) Activity of in vivo canine ventricular neurons. Am J Physiol Heart Circ Physiol 258:H326–H336. doi: 10.1152/ajpregu.00183.2004Armour JA, Hopkins DA (1990b) Activity of canine in situ left atrial ganglion neurons. Am J Physiol Heart Circ Physiol 259:H1207–H1215Armour JA (2004) Cardiac neuronal hierarchy in health and disease. Am J Physiol Regul Integr Comp Physiol 287:R262–R271Armour JA, Murphy DA, Yuan BX, Macdonald S, Hopkins DA (1997) Gross and microscopic anatomy of the human intrinsic cardiac nervous system. Anat Rec 247:289–298Bedford TG, Tipton CM (1987) Exercise training and the arterial baroreflex. J Appl Physiol 63:1926–1932Bonaduce D, Petretta M, Cavallaro V, Apicella C, Ianniciello A, Romano M, Breglio R, Marciano F (1998) Intensive training and cardiac autonomic control in high level athletes. Med Sci Sports Exerc 30:691–696Brack KE, Coote JH, Ng GA (2011) Vagus nerve stimulation protects against ventricular fibrillation independent of muscarinic receptor activation. Cardiovasc Res 91:437–446. doi: 10.1093/cvr/cvr105Brorson L, Conradson TB, Olsson B, Varnauskas E (1976) Right atrial monophasic action potential and effective refractory periods in relation to physical training and maximal heart rate. Cardiovasc Res 10:160–168Carmeliet E, Mubagwa K (1998) Antiarrhythmic drugs and cardiac ion channels: mechanisms of action. Prog Biophys Mol Biol 70:1–72Chorro FJ, Cánoves J, Guerrero J, Mainar L, Sanchis J, Such L, López-Merino V (2000) Alteration of ventricular fibrillation by flecainide, verapamil, and sotalol: an experimental study. Circulation 101:1606–1615Di Carlo SE, Bishop VS (1990) Exercise training enhances cardiac afferent inhibition of baroreflex function. Am J Physiol 258:212–220Gagliardi M, Randall WC, Bieger D, Wurster RD, Hopkins DA, Armour JA (1988) Activity of in vivo canine cardiac plexus neurons. Am J Physiol Heart Circ Physiol 255:H789–H800Gao L, Wang W, Liu D, Zucker IH (2007) Exercise training normalizes sympathetic outflow by central antioxidant mechanisms in rabbits with pacing-induced chronic heart failure. Circulation 115:3095–3102. doi: 10.1161/CIRCULATIONAHA.106.677989Gaustad SE, Rolim N, Wisløff U (2010) A valid and reproducible protocol for testing maximal oxygen uptake in rabbits. Eur J Cardiovasc Prev Rehabil 17:83–88. doi: 10.1097/HJR.0b013e32833090c4Gómez-Cabrera MC, Borrás C, Pallardó FV, Sastre J, Ji LL, Viña J (2005) Decreasing xanthine oxidase-mediated oxidative stress prevents useful cellular adaptations to exercise in rats. J Physiol 567:113–120. doi: 10.1113/jphysiol.2004.080564Gray AL, Johnson TA, Ardell JL, Massari VJ (2004) Parasympathetic control of the heart II. A novel interganglionic intrinsic cardiac circuit mediates neural control of heart rate. J Appl Physiol 96:2273–2278. doi: 10.1152/japplphysiolHamilton KL, Powers SK, Sugiura T, Kim S, Lennon S, Tumer N, Mehta JL (2001) Short-term exercise training can improve myocardial tolerance to I/R without elevation in heat shock proteins. Am J Physiol Heart Circ Physiol 281:1346–1352Inoue H, Zipes DP (1987) Changes in atrial and ventricular refractoriness and atrioventricular nodal conduction produced by combinations of vagal and sympathetic stimulation that result in a constant spontaneous sinus cycle length. Circ Res 60:942–951Jew KN, Olsson MC, Mokelke EA, Palmer BM, Moore RL (2001) Endurance training alters outward K+ current characteristics in rat cardiocytes. J Appl Physiol 90:1327–1333Johnson TA, Gray AL, Lauenstein JM, Newton SS, Massari VJ (2004) Parasympathetic control of the heart I. An interventriculo-septal ganglion is the major source of the vagal intracardiac innervation of the ventricles. J Appl Physiol 96:2265–2272. doi: 10.1152/japplphysiol.00620.2003Katona PG, McLean M, Dighton DH, Guz A (1982) Sympathetic and parasympathetic cardiac control in athletes and nonathletes at rest. J Appl Physiol 52:1652–1657Lewis SF, Nylander E, Gad P, Areskog N (1980) Non-autonomic component in bradycardia of endurance trained men at rest and during exercise. Acta Physiol Scand 109:297–305Litovsky SH, Antzelevitch C (1990) Differences in the electrophysiological response of canine ventricular subendocardium and subepicardium to acetylcholine and isoproterenol. A direct effect of acetylcholine in ventricular myocardium. Circ Res 67:615–627Löffelholz K (1981) Release of acetylcholine in the isolated heart. Am J Physiol 240(4):H431–H440Lopatin AN, Nichols CG (2001) Inward rectifiers in the heart: an update on I(K1). J Mol Cell Cardiol 33:625–638. doi: 10.1006/jmcc.2001.1344Mace LC, Palmer BM, Brown DA, Jew KN, Lynch JM, Glunt JM, Parsons TA, Cheung JY, Moore RL (2003) Influence of age and run training on cardiac Na+/Ca2+ exchange. J Appl Physiol 95:1994–2003. doi: 10.1152/japplphysiol.00551.2003Martins JB, Zipes DP (1980) Effects of sympathetic and vagal nerves on recovery properties of the endocardium and epicardium of the canine left ventricle. Circ Res 46:100–110Mezzani A, Giovannini T, Michelucci A, Padeletti L, Resina A, Cupelli V, Musante R (1990) Effects of training on the electrophysiologic properties of atrium and accessory pathway in athletes with Wolff–Parkinson–White syndrome. Cardiology 77:295–302Mokelke EA, Palmer BM, Cheung JY, Moore RL (1997) Endurance training does not affect intrinsic calcium current characteristics in rat myocardium. Am J Physiol Heart Circ Physiol 273:H1193–H1197Mont L, Elosua R, Brugada J (2009) Endurance sport practice as a risk factor for atrial fibrillation and atrial flutter. Europace 11:11–17. doi: 10.1093/europace/eun289Moore RL, Korzick DH (1995) Cellular adaptations of the myocardium to chronic exercise. Prog Cardiovasc Dis 37:371–396Negrao CE, Moreira ED, Santos MC, Farah VM, Krieger EM (1992) Vagal function impairment after exercise training. J Appl Physiol 72:1749–1753Ng GA, Brack KE, Coote JH (2001) Effects of direct sympathetic and vagus nerve stimulation on the physiology of the whole heart—a novel model of isolated Langendorff perfused rabbit heart with intact dual autonomic innervation. Exp Physiol 86:319–329Nylander E, Sigvardsson K, Kilbom A (1982) Training-induced bradycardia and intrinsic heart rate in rats. Eur J Appl Physiol Occup Physiol 48:189–199Panfilov AV (2006) Is heart size a factor in ventricular fibrillation? Or how close are rabbit and human hearts? Heart Rhythm 3:862–864. doi: 10.1016/j.hrthm.2005.12.022Papka RE (1976) Studies of cardiac ganglia in pre- and postnatal rabbits. Cell Tissue Res 175:17–35Pardini BJ, Patel KP, Schmid PG, Lund DD (1987) Location, distribution and projections of intracardiac ganglion cells in the rat. J Auton Nerv Syst 20:91–101Scott AS, Eberhard A, Ofir D, Benchetrit G, Dinh TP, Calabrese P, Lesiuk V, Perrault H (2004) Enhanced cardiac vagal efferent activity does not explain training-induced bradycardia. Auton Neurosci 112:60–68. doi: 10.1016/j.autneu.2004.04.006Seals DR, Chase PB (1989) Influence of physical training on HR variability and baroreflex circulatory control. J Appl Physiol 66:1886–1895Shi X, Stevens GHJ, Foresman BH, Stern SA, Raven PB (1995) Autonomic nervous system control of the heart: endurance exercise training. Med Sci Sports Exerc 27:1406–1413Snyders DJ (1999) Structure and function of cardiac potassium channels. Cardiovasc Res 42:377–390Stein R, Moraes RS, Cavalcanti AV, Ferlin EL, Zimerman LI, Ribeiro JP (2000) Atrial automaticity and atrioventricular conduction in athletes: contribution of autonomic regulation. 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Norm reasoning services

Norms are used in open Multi-Agent Systems as a formal specification of deontic statements aimed at regulating the actions of agents and the interactions among them. In this paper, we propose a set of services facilitating the development of both non-normative and normative agents for norm-governed MAS. Specifically, we propose to provide agents with norm reasoning services. These services will help agent designers/developers to programme agents that consider norm reasoning without having to implement the needed mechanisms to reason about norms by themselves. This article shows how these services perform as well as the results of the experiments that we conducted to evaluate their performance

Argumentation for multi-party privacy management

Social network services enable users to share large quantities of private information. Often, the shared information concerns individuals who are members of the social network but did not upload the information to the service. In such situations, inappropriate sharing preferences can cause conflict and threaten users’ privacy. Since related studies suggest that users prefer to solve multi-party privacy conflicts through negotiation, we introduce a novel approach based on negotiation through arguments. In our approach, users propose privacy settings and support their proposals with logical arguments. The final decision is based on a setting supported by sound arguments

'Do horses cause divorces?':Autoethnographic insights on family, relationships and resource-intensive leisure

Equestrian leisure is resource-intensive and requires significant investment of time, money, effort and emotion. In this paper we consider these demands within the context of personal and family relationships. Using autoethnographic methods we use our own relationships with horses and with our human partners to explore the issues and tensions than can arise when one person engages in such an intense and demanding leisure pursuit. We argue that support from partners is essential, but may often be underpinned by some resentment towards the horse(s) and the commitment they entail. Framed within the context of gendered family relationships and gendered leisure, we suggest that women’s involvement in resource-hungry leisure, such as equestrianism, is filtered through traditional gender power relations and that constant negotiation and compromise is required to enable women to engage in demanding leisure activities

Effect of chronic exercise on myocardial electrophysiological heterogeneity and stability. Role of intrinsic cholinergic neurons: A study in the isolated rabbit heart

[EN] A study has been made of the effect of chronic exercise on myocardial electrophysiological heterogeneity and stability, as well as of the role of cholinergic neurons in these changes. Determinations in hearts from untrained and trained rabbits on a treadmill were performed. The hearts were isolated and perfused. A pacing electrode and a recording multielectrode were located in the left ventricle. The parameters determined during induced VF, before and after atropine (1 mu M), were: fibrillatory cycle length (VV), ventricular functional refractory period (FRPVF), normalized energy (NE) of the fibrillatory signal and its coefficient of variation (CV), and electrical ventricular activation complexity, as an approach to myocardial heterogeneity and stability. The VV interval was longer in the trained group than in the control group both prior to atropine (78 +/- 10 vs. 68 +/- 10 ms) and after atropine (76 +/- 8 vs. 67 +/- 10 ms). Likewise, FRPVF was longer in the trained group than in the control group both prior to and after atropine (53 +/- 8 vs. 42 +/- 7 ms and 50 +/- 6 vs. 40 +/- 6 ms, respectively), and atropine did not modify FRPVF. The CV of FRPVF was lower in the trained group than in the control group prior to atropine (12.5 +/- 1.5% vs. 15.1 +/- 3.8%) and, decreased after atropine (15.1 +/- 3.8% vs. 12.2 +/- 2.4%) in the control group. The trained group showed higher NE values before (0.40 +/- 0.04 vs. 0.36 +/- 0.05) and after atropine (0.37 +/- 0.04 vs. 0.34 +/- 0.06; p = 0.08). Training decreased the CV of NE both before (23.3 +/- 2% vs. 25.2 +/- 4%; p = 0.08) and after parasympathetic blockade (22.6 +/- 1% vs. 26.1 +/- 5%). Cholinergic blockade did not modify these parameters within the control and trained groups. Activation complexity was lower in the trained than in the control animals before atropine (34 +/- 8 vs. 41 +/- 5), and increased after atropine in the control group (41 +/- 5 vs. 48 +/- 9, respectively). Thus, training decreases the intrinsic heterogeneity of the myocardium, increases electrophysiological stability, and prevents some modifications due to muscarinic block.This research was supported by the Spanish Ministry of Education and Science, (DEP2007-73234-C03-01 to AMA), http://www.mecd.gob.es/portada-mecd/; and the Generalitat Valenciana (PROMETEO 2010/093 to FJC, and FPI/2008/003 to MZ), http://www.gva.es/va/inicio/presentacion; jsessionid=ydprbDQZTsCTz85W1Such-Miquel, L.; Brines-Ferrando, L.; Alberola, A.; Zarzoso Muñoz, M.; Chorro Gasco, FJ.; Guerrero-Martínez, JF.; Parra-Giraldo, G.... (2018). Effect of chronic exercise on myocardial electrophysiological heterogeneity and stability. Role of intrinsic cholinergic neurons: A study in the isolated rabbit heart. PLoS ONE. 13(12). https://doi.org/10.1371/journal.pone.0209085S1312Billman, G. E. (2002). Aerobic exercise conditioning: a nonpharmacological antiarrhythmic intervention. Journal of Applied Physiology, 92(2), 446-454. doi:10.1152/japplphysiol.00874.2001Billman, G. E. (2006). A comprehensive review and analysis of 25 years of data from an in vivo canine model of sudden cardiac death: Implications for future anti-arrhythmic drug development. Pharmacology & Therapeutics, 111(3), 808-835. doi:10.1016/j.pharmthera.2006.01.002Dor-Haim, H., Berenfeld, O., Horowitz, M., Lotan, C., & Swissa, M. (2013). Reduced Ventricular Arrhythmogeneity and Increased Electrical Complexity in Normal Exercised Rats. PLoS ONE, 8(6), e66658. doi:10.1371/journal.pone.0066658Hamer, M., & Stamatakis, E. (2008). Physical Activity and Cardiovascular Disease: Directions for Future Research. The Open Sports Sciences Journal, 1(1), 1-2. doi:10.2174/1875399x00801010001Powers, S. K., Smuder, A. J., Kavazis, A. N., & Quindry, J. C. (2014). Mechanisms of Exercise-Induced Cardioprotection. Physiology, 29(1), 27-38. doi:10.1152/physiol.00030.2013Hull, S. S., Vanoli, E., Adamson, P. B., Verrier, R. L., Foreman, R. D., & Schwartz, P. J. (1994). Exercise training confers anticipatory protection from sudden death during acute myocardial ischemia. Circulation, 89(2), 548-552. doi:10.1161/01.cir.89.2.548Hajnal, Á., Nagy, O., Litvai, Á., Papp, J., Parratt, J. R., & Végh, Á. (2005). Nitric oxide involvement in the delayed antiarrhythmic effect of treadmill exercise in dogs. Life Sciences, 77(16), 1960-1971. doi:10.1016/j.lfs.2005.02.015Such, L., Alberola, A. M., Such-Miquel, L., López, L., Trapero, I., Pelechano, F., … Chorro, F. J. (2008). Effects of chronic exercise on myocardial refractoriness: a study on isolated rabbit heart. Acta Physiologica, 193(4), 331-339. doi:10.1111/j.1748-1716.2008.01851.xZarzoso, M., Such-Miquel, L., Parra, G., Brines-Ferrando, L., Such, L., Chorro, F. J., … Alberola, A. (2011). The training-induced changes on automatism, conduction and myocardial refractoriness are not mediated by parasympathetic postganglionic neurons activity. European Journal of Applied Physiology, 112(6), 2185-2193. doi:10.1007/s00421-011-2189-4Billman, G. E. (2009). Cardiac autonomic neural remodeling and susceptibility to sudden cardiac death: effect of endurance exercise training. American Journal of Physiology-Heart and Circulatory Physiology, 297(4), H1171-H1193. doi:10.1152/ajpheart.00534.2009HAN, J., & MOE, G. K. (1964). Nonuniform Recovery of Excitability in Ventricular Muscle. Circulation Research, 14(1), 44-60. doi:10.1161/01.res.14.1.44Beaumont, E., Salavatian, S., Southerland, E. M., Vinet, A., Jacquemet, V., Armour, J. A., & Ardell, J. L. (2013). Network interactions within the canine intrinsic cardiac nervous system: implications for reflex control of regional cardiac function. The Journal of Physiology, 591(18), 4515-4533. doi:10.1113/jphysiol.2013.259382Armour, J. A. (2008). Potential clinical relevance of the ‘little brain’ on the mammalian heart. Experimental Physiology, 93(2), 165-176. doi:10.1113/expphysiol.2007.041178Abramochkin, D. V., Nurullin, L. F., Borodinova, A. A., Tarasova, N. V., Sukhova, G. S., Nikolsky, E. E., & Rosenshtraukh, L. V. (2009). Non-quantal release of acetylcholine from parasympathetic nerve terminals in the right atrium of rats. Experimental Physiology, 95(2), 265-273. doi:10.1113/expphysiol.2009.050302CHORRO, F. J., CANOVES, J., GUERRERO, J., MAINAR, L., SANCHIS, J., SORIA, E., … LOPEZ-MERINO, V. (2000). Opposite Effects of Myocardial Stretch and Verapamil on the Complexity of the Ventricular Fibrillatory Pattern: An Experimental Study. Pacing and Clinical Electrophysiology, 23(11), 1594-1603. doi:10.1046/j.1460-9592.2000.01594.xSuch, L., Rodriguez, A., Alberola, A., Lopez, L., Ruiz, R., Artal, L., … Chorro, F. J. (2002). 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BFF: A Tool for Eliciting Tie Strength and User Communities in Social Networking Services

López Fogués, R.; Such Aparicio, JM.; Espinosa Minguet, AR.; García-Fornes, A. (2014 Abstract The use of social networking services (SNSs) such as Facebook has explosively grown in the last few years. Users see these SNSs as useful tools to find friends and interact with them. Moreover, SNSs allow their users to share photos, videos, and express their thoughts and feelings. However, users are usually concerned about their privacy when using SNSs. This is because the public image of a subject can be affected by photos or comments posted on a social network. In this way, recent studies demonstrate that users are demanding better mechanisms to protect their privacy. An appropriate approximation to solve this could be a privacy assistant software agent that automatically suggests a privacy policy for any item to be shared on a SNS. The first step for developing such an agent is to be able to elicit meaningful information that can lead to accurate privacy policy predictions. In particular, the information needed is user communities and the strength of users' relationships, which, as suggested by recent empirical evidence, are the most important factors that drive disclosure in SNSs. Given the number of friends that users can have and the number of communities they may be involved on, it is infeasible that users are able to provide this information without the whole eliciting process becoming confusing and time consuming. In this work, we present a tool called Best Friend Forever (BFF) that automatically classifies the friends of a user in communities and assigns a value to the strength of the relationship ties to each one. We also present an experimental evaluation involving 38 subjects that showed that BFF can significantly alleviate the burden of eliciting communities and relationship strength