Nasze seminarium zakładowe odbywa się w środy 14:15-15:45 w sali 4050
2015-06-03: Mateusz Dębowski (Uniwersytet Warszawski)
Title: A mathematical model for pancreatic cancer growth and treatments
Abstract: I will present results of Y. Lauzoun, C. Xue, G. B. Lesinski and A. Friedman from 2014. They developed model of pancreatic cancer and shows that drugs aimed at suppressing cancer growth are effective only if the immune induced cancer cell death lies within a specific range. Moreover the model results suggest that tumor growth is affected by feedback loops between tumor cells, endothelial cells and the immune response. This could be helpful in choosing the optimal intervention agains cancer.
2015-05-27: Yaroslav Bihun (Yuriy Fedkovych Chernivtsi National University, Department of Applied Mathematics and Information Technology)
Title: Systems of Multifrequency Differential Equations with Delay and their Application in Mathematical Modelling of Immune Response in Infectious Diseases
Abstract: The obtained results in this work are a further development for multifrequency systems with constant and linear delay results of A.M. Samoylenko and R.I. Petryshyn for ordinary differential equations. New theorems on the existence and uniqueness of the solution of multifrequency systems of differential equations with linearly transformed argument and integral boundary conditions with functions depending on slow time have been proven and averaging method for such boundary problems has been substantiated. New assessment of the averaging method, which obviously depends on the small parameter for Noether boundary problem has been established. Estimation error of the averaging method has been defined. Circuit averaging illustrated on model examples have been given.
2015-05-20: Magdalena Bogdańska (Uniwersytet Warszawski)
Title: Mathematical model of brain tumour with glia-neuron interactions and chemotherapy treatment
Abstract: I will present recent results of Iarosz et al., who propose a mathematical model for the evolution of a brain tumour under the influence of chemotherapeutic agents. Model describes the interactions among glial cells, neurons and glioma with a chemotherapy to suppress the brain tumour. The novelty in this model is the glial effect on the neurons. There are studied conditions for the elimination of glioma and values of the parameters for which the inhibition of the glioma growth is obtained with a minimal loss of a healthy cells.
2015-05-06: Zbigniew Peradzyński (Uniwersytet Warszawski)
Title: Fale wapniowe generowane napływem wapnia do komórki z przestrzeni międzykomórkowej poprzez mechanicznie otwierane kanały jonowe
Abstract: Obserwacje wskazują, ze tego typu fale są dość powszechne. Ponadto mają one prędkości o rząd większe niż zwykłe fale wapniowe podtrzymywane przez autokatalityczne wydzielanie wapnia z magazynów wapniowych. W wykładzie zaproponujemy matematyczny model takich fal oraz omówimy własności w zależności od występujących tam parametrów. Jako ciekawostka matematyczna pojawia się tam tzw. dynamiczny warunek brzegowy.
2015-04-29: Agnieszka Bartłomiejczyk (Politechnika Gdańska)
Title: Modelling gene expression of Hes1 protein
Abstract: We analyze a model of gene transcription and protein synthesis and we investigate the effect of multiple binding sites in the Hes1 promoter. Hes1 protein, a transcriptional repressor, inhibits its own transcription by directly binding to its own promoter, which blocks transcription of hes1 mRNA. When the transcription of Hes1 mRNA is repressed by this negative feedback, Hes1 protein soon
disappears because it is rapidly degraded by the ubiquitin-proteasome pathway. This is joint work with Marek Bodnar.
2015-04-22: Beata Jackowska-Zduniak (SGGW)
Title: Mathematical model of the av nodal double response tachycardia and double-fire pathology
Abstract: A proposed model consisting of two coupled models (Hodgkin-Huxley model and Yanighara-Noma-Irisawa model) is considered as a description of the heart’s action potential. System of ordinary differential equations is used to recreate pathological behaviour in the conducting heart’s system such as rare arrhythmia, called double fire and the most common tachycardia AVNRT. We introduce to our system three types of couplings (bidirectional couplings, unidirectional couplings and feedbacks) and delay in order to reproduce the different types of AVNRT.
2015-04-15: Agnieszka Wiszniewska-Matyszkiel, Marek Bodnar
Title: Dynamic Oligopoly with Sticky Prices -- Off-Steady State Analysis - continuation
2015-04-08: Agnieszka Wiszniewska-Matyszkiel, Marek Bodnar
Title: Dynamic Oligopoly with Sticky Prices -- Off-Steady State Analysis
Abstract: We present a comprehensive analysis of the model of oligopoly with sticky prices with full analysis of prices' behaviour outside its steady state level in the infinite horizon case. An exhaustive proof of optimality is given in both open loop and closed loop cases.
2015-03-25: Magdalena Bogdańska (PhD Student WMIM UW)
Title: Mathematical model suggests a way to assess low grade glioma malignancy
Abstract: Low grade gliomas (LGGs) are incurable primary brain tumours with typically slow evolution. For management decisions it is essential to find a method to verify tumours aggressiveness and test their response to standard therapies with the lowest toxicity possible. We propose a mathematical model of LGG growth and its response to chemotherapy which agrees with patients' data. Moreover, we provide estimated formula for time of tumour response to therapy, which can be used as a measure of tumour aggressiveness. Finally, we suggest chemotherapy fractionation scheme that might be therapeutically useful to predict the tumour growth and further prognosis.
2015-03-11: Urszula Zawadzka (PhD Student MiSDoMP)
Title: Modelowanie w archeologii osadnictwa
Abstract: "...Archeologia to dziedzina, która próbuje wyjaśnić wzorce nieuchwytnych zachowań, nieobserwowanych hominidów z niejednoznacznych śladów w złych próbach...". Powyższy cytat z Davida Clarke obrazuje większość problemów z jakimi spotykają się archeolodzy próbując modelować zachowania ludzkie w przeszłości.
W prezentacji zasygnalizuję najważniejsze kierunki w jakich rozwija się modelowanie w archeologii. Następnie zaprezentuję wyniki jakie uzyskali Andrew Bevan oraz Alan Wilson badając przy użyciu modeli osadnictwo z okresu epoki brązu na Krecie.
2015-03-04: Mateusz Dębowski (PhD Student WMIM)
Title: Cell cycle model: entry into mitosis
Abstract: James Ferrell has investigated entry in mitosis and described it by bistability (switches). He looked on this process globally (in some way). We are considering this entry locally in one of two stability states. The new thing is that, there is important protein which inhibits the whole process.
2015-01-21: Oskar Górniewicz (PhD Student)
Title: Note on the Fixed Point Property
Abstract: I will make introduction to prove that absolute approximative retracts and absolute multiretracts spaces have the fi xed point property both for singlevalued continous mappings and multivalued upper semi-continous mappings with R-delta values.
2014-12-3: Sudip Samanta, Postdoctoral Research Fellow (Erazmus)
Title: Effect of awareness program and delay in the epidemic outbreak
Abstract: The aim of this presentation is to discuss my previous research work and try to explore the possibilities for extensions of previous work. We propose and analyze mathematical models to assess the effect of awareness programs by media on the prevalence of infectious diseases. Awareness programs may induce behavioral changes in the population, and divide the susceptible class into two subclasses with different infectivity rates. The biologically feasible equilibria and their stability properties are analyzed and discussed. The model analysis reveals that the rate of executing awareness programs has a substantial effect over the system and sustained oscillation may arise with increasing its value above a threshold. This threshold poses a challenge to control the epidemic. We further improve and study the model by introducing two time-delay factors, one for the time lag in memory fading of aware people and one for the delay between cases of disease occurring and mounting awareness programs. We study various cases for the time delays and show that in general the system develops limit cycle oscillation through a Hopf bifurcation for increasing time delays. To verify our analytical findings, the numerical simulations of the model, using realistic parameters for Pneumococcus are performed.
2014-12-3: Emad Rezk (PhD Student z Egiptu)
Title: Angiogenesis model with distributed delay
Abstract: The aim of this presentation is to show the results of the work done during the stay in Poland. The model proposed by Bodnar et al. (2013) was changed to consider distributed delays instead of discrete delays. Results concerning existence of global positive solutions and stability of steady states will be presented.
2014-11-26: Błażej Miasojedow
Title: Ukryte modele Markowa, przykłady i algorytmy - kontynuacja
2014-11-19: Wojciech Niemiro
Title: Ukryte modele Markowa, przykłady i algorytmy
Abstract: Przedstawimy ogólny schemat ukrytych modeli Markow I parę przykładów zastosowań. W miarę naszych możliwości postaramy się skupić na zastosowaniach w biologii I chemii. Zrobimy przegląd algorytmów obliczeniowych I symulacyjnych, ze szczególnym uwzględnieniem MCMC dla ukrytych procesów z czasem ciągłym, które wydaja się najważniejsze w modelowaniu kinetyki reakcji chemicznych (i dla których mamy dość świeże wyniki własne).
2014-11-5: Krzysztof R. Apt
Title: Potentials and their uses in strategic games
Abstract: The idea of a potential was introduced in the influential paper of Monderer and Shapley in 1994. It is a technique that allows one to conclude that a strategic game has a Nash equilibrium. We shall discuss the main aspects of this paper and subsequently illustrate other uses of potentials in our recent work on coordination games on graphs. In each such game the players are the nodes of a graph. Each node selects a colour from a set of colours (privately) available for it. The payoff to a node is the number of neighbours who chose the same colour. These games capture the idea of coordination in a local setting strategies. We shall focus on the issue of existence of Nash equilibria, k-equilibria and strong equilibria. This is a joint work with Mona Rahn, Guido Schaefer and Sunil Simon.
2014-10-29: Małgorzata Półtorak
Title: Functioning in close relationships: mathematical model
Abstract: I will present modified Felmlee & Greenberg (1999) model of the dynamics of relationships between two persons. Using various parameters of the model we are able to explain various types of relationships and give some suggestions to make the relationship better.
2014-10-22: Je-Chiang Tsai (Chung Cheng University, Taiwan)
Title: Curvature dependence of propagating velocity for a simplied calcium model
Abstract: It is known that the relation between curvature and wave speed plays a key role in the propagation of two-dimensional waves in an excitable model. For typical excitable models (e.g., the FitzHugh-Nagumo (FHN) model), such a relation is believed to obey the linear eikonal equation, which states that the relation between the normal velocity and the local curvature is approximately linear. In this talk, we show that for a caricature model of intracellular calcium dynamics, although its temporal dynamics can be investigated by analogy with the FHN model, the curvature relation does not obey the linear eikonal equation even in the limiting case. Hence this caricature calcium model may be an unexpected excitable system, whose wave propagation properties cannot be always understood by analogy with the FHN model.
2014-10-15: Wojciech Borkowski (Instytut Studiów Społecznych im. prof. B. Zajonca, UW)
Title: Dynamiczna Psychologia Społeczna
Abstract: W istniejącym już od ponad 20 lat "Ośrodku badania układów złożonych i nowych technologii" w Instytucie Studiów Społecznych UW, zajmujemy się zastosowaniami teorii układów złożonych i informatyki w psychologii społecznej (dział ten bywa nazywany "dynamiczną psychologią społeczną"), ale także w obszarach stanowiących dla niej tło - psychologii "ja", dynamice sieci neuronowych czy, z drugiej strony, procesów ewolucyjnych. Jednym z głównych wątków badawczych i teoretycznych były dla nas zawsze procesy wpływu społecznego, który uznajemy za podstawowy mechanizm sterujący uwspólnianiem informacji adaptacyjnej w ludzkich społeczeństwach, choć w tej chwili praktyka badań znacznie się rozszerzyła w kierunku informatyki i ekonomi.
Poza różnorodnymi metodami badań psychologicznych i socjologicznych centralną metodą badawczych jest modelowanie komputerowe dynamiki procesów psychicznych, społecznych i ewolucyjnych za pomocą symulacji komputerowych, jako że narzędzie to pozwala badać zjawiska emergentne, powszechne w tych systemach. Stosujemy szeroką gamę modeli: od automatów komórkowych, algorytmów genetycznych, sztucznych sieci neuronowych i innych modeli sieciowych, po utworzone na ich bazie "minimalistyczne modele agentowe" będące naszą główną specjalnością, oraz rozbudowane - "realistyczne" modele agentowe.
Kilka dosyć aktualnych linków rozszerzających temat:
- Dynamical Minimalism: Why Less is More in Psychology, Andrzej Nowak http://www.ncbi.nlm.nih.gov/pubmed/15223518, http://psr.sagepub.com/content/8/2/183.full.pdf+html
- Culture Change: The Perspective of Dynamical Minimalism, Andrzej Nowak, Wouter de Raad, and Wojciech Borkowski rozdział http://global.oup.com/academic/product/advances-in-culture-and-psychology-9780199840694
- Why Simulate? To Develop a Mental Model, Andrzej Nowak, Agnieszka Rychwalska and Wojciech Borkowski http://jasss.soc.surrey.ac.uk/16/3/12.html
- UKŁADY ZŁOŻONE W NAUKACH SPOŁECZNYCH Wybrane zagadnienia (książka) http://scholar.com.pl/sklep.php?md=products&id_p=2029
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