BEGIN:VCALENDAR
VERSION:2.0
PRODID:-//Namur Institute For Complex Systems - ECPv6.15.14//NONSGML v1.0//EN
CALSCALE:GREGORIAN
METHOD:PUBLISH
X-WR-CALNAME:Namur Institute For Complex Systems
X-ORIGINAL-URL:https://www.naxys.be
X-WR-CALDESC:Events for Namur Institute For Complex Systems
REFRESH-INTERVAL;VALUE=DURATION:PT1H
X-Robots-Tag:noindex
X-PUBLISHED-TTL:PT1H
BEGIN:VTIMEZONE
TZID:Europe/Paris
BEGIN:DAYLIGHT
TZOFFSETFROM:+0100
TZOFFSETTO:+0200
TZNAME:CEST
DTSTART:20160327T010000
END:DAYLIGHT
BEGIN:STANDARD
TZOFFSETFROM:+0200
TZOFFSETTO:+0100
TZNAME:CET
DTSTART:20161030T010000
END:STANDARD
BEGIN:DAYLIGHT
TZOFFSETFROM:+0100
TZOFFSETTO:+0200
TZNAME:CEST
DTSTART:20170326T010000
END:DAYLIGHT
BEGIN:STANDARD
TZOFFSETFROM:+0200
TZOFFSETTO:+0100
TZNAME:CET
DTSTART:20171029T010000
END:STANDARD
BEGIN:DAYLIGHT
TZOFFSETFROM:+0100
TZOFFSETTO:+0200
TZNAME:CEST
DTSTART:20180325T010000
END:DAYLIGHT
BEGIN:STANDARD
TZOFFSETFROM:+0200
TZOFFSETTO:+0100
TZNAME:CET
DTSTART:20181028T010000
END:STANDARD
END:VTIMEZONE
BEGIN:VEVENT
DTSTART;TZID=Europe/Paris:20170502T130000
DTEND;TZID=Europe/Paris:20170502T140000
DTSTAMP:20260409T054936
CREATED:20170308T152719Z
LAST-MODIFIED:20170416T103118Z
UID:149-1493730000-1493733600@www.naxys.be
SUMMARY:Jan Baert (UGent)
DESCRIPTION:Title: Environmental dependency of biodiversity effects on ecosystem functioning \nAbstract: Expanding human activities are increasingly interfering with Earth’s biogeochemical cycles. This has led to unprecedented global changes in biodiversity and environmental conditions. In the past 3 decades\, ecologists have principally been focusing on whether the functioning of an ecosystem depends on the number of species it contains. There is now ample evidence that biodiversity-ecosystem functioning relationships are generally positive\, and ecosystem function provisioning is at risk by biodiversity loss. However\, evidence is also mounting that the relationship between biodiversity and ecosystem functioning\, and therefore also the consequences of biodiversity changes\, depend on the environmental conditions. In my work\, I ai to explain how biodiversity-ecosystem functioning relationships are affected by changes in environmental conditions. Theoretical models are thereby combined with microcosm experiments to demonstrate how environmental changes lead to predictable changes in biodiversity effects on ecosystem functioning\, and how these changes depend the type of species interactions and species sensitivities to environmental changes. As such\, the presented framework offers new insights in the combined effect of upcoming biodiversity and environmental changes for ecosystem function provisioning.
URL:https://www.naxys.be/event/jan-baert-ugent/
LOCATION:Seminar room\, Rempart de la Vierge 8\, Namur\, 1170
CATEGORIES:NAXYS Seminar
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=Europe/Paris:20170509T130000
DTEND;TZID=Europe/Paris:20170509T140000
DTSTAMP:20260409T054936
CREATED:20170308T154206Z
LAST-MODIFIED:20170428T110726Z
UID:152-1494334800-1494338400@www.naxys.be
SUMMARY:Nikos Kouvaris ( University Pompeu Fabra)
DESCRIPTION:Title: Pattern formation in bistable networks: Theory and applications to chemical reactions \n  \nAbstract: \nSelf-organization processes in complex networks is an interdisciplinary research field with great theoretical interest and many potential applications in chemistry and biology. Stationary localized patterns constitute a classical example of self-organization; they can spontaneously be generated by the Turing mechanism\, as it has been reported in both continuous and networked media. However\, an alternative mechanism for the emergence of stationary patterns in networks was recently discovered [1-4]. We have experimentally demonstrated and theoretically analyzed that bistable networks can support a rich variety of stationary patterns determined by the network architecture and the initial conditions [2\,3]. By applying a localized perturbation to a network node or a subset of nodes\, we demonstrate the subsequent spreading\, pinning\, or retraction of the activations; such analysis enables the characterization of the formation of stationary patterns of localized activity. Weak coupling results in trivial pinned states where the activation is stationary. At strong coupling\, a uniform state is expected with active or inactive elements at small or large nodes degree\, respectively. Nontrivial stationary spatial patterns\, corresponding to an activation pinning\, are predicted to occur at nodes with intermediate degrees and at intermediate coupling strengths. The results are confirmed in experiments with networks of coupled bistable electrochemical reactions. Although our experimental system is actually more complex than the simplifying assumptions under which the theory was constructed\, the results show a surprisingly good agreement. This indicates that the found pattern formation mechanism is robust and generic. \nIn this talk we discuss theoretical and experimental studies with bistable chemical reactions organized in tree [1\,2] and star [3] networks. These results are relevant for large random networks [2]. Mechanisms for the control and deliberate design of such patterns [4] will also be considered. \nReferences:\n———–\n1. N. E. Kouvaris\, H. Kori and A. S. Mikhailov\, PLoS ONE 7\, e45029 (2012).\n2. N. E. Kouvaris\, M. Sebek\, A. S. Mikhailov and I. Z. Kiss\, Angew. Chem. Int. Ed.\, 55\, 13267-13270 (2016).\n3. N. E. Kouvaris\, M. Sebek\, A. Iribarne\, A. Diaz-Guilera and I. Z. Kiss\, Phys. Rev. E 95\, 042203 (2017).\n4. N. E. Kouvaris and A. S. Mikhailov\, Europhys. Lett. 102\, 16003 (2013).
URL:https://www.naxys.be/event/nikos-kouvaris-university-pompeu-fabra/
LOCATION:Seminar room\, Rempart de la Vierge 8\, Namur\, 1170
CATEGORIES:NAXYS Seminar
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=Europe/Paris:20170523T130000
DTEND;TZID=Europe/Paris:20170523T140000
DTSTAMP:20260409T054936
CREATED:20170318T163007Z
LAST-MODIFIED:20170514T143251Z
UID:161-1495544400-1495548000@www.naxys.be
SUMMARY:Stefano Berti (University of Lille)
DESCRIPTION:Title: Reaction-transport systems in heterogeneous environments and population dynamics \nAbstract: Understanding the conditions ensuring the persistence of a population or determining the efficiency of its invasion into a new territory are issues of primary importance in population biology. A convenient conceptual framework to study these problems from a theoretical point of view is offered by reaction-transport equations. Taking this modeling approach\, in the first part of the talk I present a study on the evolution of a population in a heterogeneous environment in the presence of advection. The habitat consists of a periodic alternation of favorable and unfavorable patches where the population grows according to logistic dynamics and dies at a fixed rate\, respectively. I show that the population can survive and invade the habitat only above a critical size of the favorable patches and below a critical velocity of the medium. I characterize the survival/extinction transition\, and I present some analytical and numerical results on the invasion speed. Then\, I discuss some limitations of this description\, extending the analysis to a model with a growth term accounting for decreased reproductive power at low population densities. The phenomenology of this model is found to be richer when varying the advection intensity.\nIn the second part of the talk I discuss some effects of discreteness and demographic stochasticity on the extinction dynamics of a population confined in a favorable patch (an oasis) surrounded by a deadly environment. For this purpose\, I introduce an individual-based reaction-diffusion model and investigate its behavior focusing on the average time to extinction and on the quasistationary distribution of the number of individuals that sets in for large enough patch sizes.
URL:https://www.naxys.be/event/stefano-berti/
LOCATION:Seminar room\, Rempart de la Vierge 8\, Namur\, 1170
CATEGORIES:NAXYS Seminar
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=Europe/Paris:20170530T130000
DTEND;TZID=Europe/Paris:20170530T140000
DTSTAMP:20260409T054936
CREATED:20170314T141110Z
LAST-MODIFIED:20170602T114233Z
UID:154-1496149200-1496152800@www.naxys.be
SUMMARY:Yannick de Decker (ULB)
DESCRIPTION:Canceled
URL:https://www.naxys.be/event/yannick-de-decker/
LOCATION:Seminar room\, Rempart de la Vierge 8\, Namur\, 1170
CATEGORIES:NAXYS Seminar
END:VEVENT
END:VCALENDAR