The Experts below are selected from a list of 201 Experts worldwide ranked by ideXlab platform
Irina Badralexi - One of the best experts on this subject based on the ideXlab platform.
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A stochastic model for intracellular Active Transport
BIOMATH, 2018Co-Authors: Raluca Purnichescu-purtan, Irina BadralexiAbstract:We develop a stochastic model for an intracellular Active Transport problem. Our aims are to calculate the probability that a molecular motor reaches a hidden target, to study what influences this probability and to calculate the time required for the molecular motor to hit the target (Mean First Passage Time). We study different biologically relevant scenarios, which include the possibility of multiple hidden targets (which breed competition) and the presence of obstacles. The purpose of including obstacles is to illustrate actual disruptions of the intracellular Transport (which can result, for example, in several neurological disorders. From a mathematical point of view, the intracellular Active Transport is modelled by two independent continuous-time, discrete space Markov chains: one for the dynamics of the molecular motor in the space intervals and one for the domain of target. The process is time homogeneous and independent of the position of the molecular motor.
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A stochastic model for Active Transport
Texts in Biomathematics, 2018Co-Authors: Raluca Purnichescu-purtan, Irina BadralexiAbstract:We develop a stochastic model for an intracellular Active Transport problem. Our aims are to calculate the probability that a molecular motor reaches a hidden target, to study what influences this probability and to calculate the time required for the molecular motor to hit the target (mean first passage time). We study different biologically relevant scenarios, which include the possibility of multiple hidden targets (which breed competition) and the presence of obstacles. The purpose of including obstacles is to illustrate actual disruptions of the intracellular Transport (which can result, for example, in several neurological disorders. From a mathematical point of view, the intracellular Active Transport is modelled by two independent continuous-time, discrete space Markov chains: one for the dynamics of the molecular motor in the space intervals and one for the domain of target. The process is time homogeneous and independent of the position of the molecular motor.
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A stochastic model for intracellular Active Transport
Biomath Communications Supplement, 2018Co-Authors: Raluca Purnichescu Purtan, Irina BadralexiAbstract:We develop a stochastic model for an intracellular Active Transport problem. Our aims are to calculate the probability that a molecular motor reaches a hidden target, to study what influences this probability and to calculate the time required for the molecular motor to hit the target (mean first passage time). We will study different biologically relevant scenarios, which include the possibility of multiple hidden targets (which breed competition), the presence of moving targets and moving obstacles. The purpose of including obstacles is to illustrate actual disruptions of the intracellular Transport (which can result, for example, in several neurological disorders [1]) From a mathematical point of view, the intracellular Active Transport is modelled by two independent continuous-time, discrete space Markov chains: one for the dynamics of the molecular motor in the space intervals and one for the domain of target. The process is time homogeneous and independent of the position of the molecular motor.
Vanessa Styles - One of the best experts on this subject based on the ideXlab platform.
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A Cahn–Hilliard–Darcy model for tumour growth with chemotaxis and Active Transport
Mathematical Models and Methods in Applied Sciences, 2016Co-Authors: Harald Garcke, Emanuel Sitka, Kei Fong Lam, Vanessa StylesAbstract:Using basic thermodynamic principles we derive a Cahn–Hilliard–Darcy model for tumour growth including nutrient diffusion, chemotaxis, Active Transport, adhesion, apoptosis and proliferation. In contrast to earlier works, the model is based on a volume-averaged velocity and in particular includes Active Transport mechanisms which ensure thermodynamic consistency. We perform a formally matched asymptotic expansion and develop several sharp interface models. Some of them are classical and some are new which for example include a jump in the nutrient density at the interface. A linear stability analysis for a growing nucleus is performed and in particular the role of the new Active Transport term is analysed. Numerical computations are performed to study the influence of the Active Transport term for specific growth scenarios.
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a cahn hilliard darcy model for tumour growth with chemotaxis and Active Transport
Mathematical Models and Methods in Applied Sciences, 2016Co-Authors: Harald Garcke, Emanuel Sitka, Vanessa StylesAbstract:Using basic thermodynamic principles we derive a Cahn–Hilliard–Darcy model for tumour growth including nutrient diffusion, chemotaxis, Active Transport, adhesion, apoptosis and proliferation. In contrast to earlier works, the model is based on a volume-averaged velocity and in particular includes Active Transport mechanisms which ensure thermodynamic consistency. We perform a formally matched asymptotic expansion and develop several sharp interface models. Some of them are classical and some are new which for example include a jump in the nutrient density at the interface. A linear stability analysis for a growing nucleus is performed and in particular the role of the new Active Transport term is analysed. Numerical computations are performed to study the influence of the Active Transport term for specific growth scenarios.
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a cahn hilliard darcy model for tumour growth with chemotaxis and Active Transport
arXiv: Analysis of PDEs, 2015Co-Authors: Harald Garcke, Emanuel Sitka, Vanessa StylesAbstract:Using basic thermodynamic principles we derive a Cahn--Hilliard--Darcy model for tumour growth including nutrient diffusion, chemotaxis, Active Transport, adhesion, apoptosis and proliferation. The model generalises earlier models and in particular includes Active Transport mechanisms which ensure thermodynamic consistency. We perform a formally matched asymptotic expansion and develop several sharp interface models. Some of them are classical and some are new which for example include a jump in the nutrient density at the interface. A linear stability analysis for a growing nucleus is performed and in particular the role of the new Active Transport term is analysed. Numerical computations are performed to study the influence of the Active Transport term for specific growth scenarios.
Harald Garcke - One of the best experts on this subject based on the ideXlab platform.
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A Cahn–Hilliard–Darcy model for tumour growth with chemotaxis and Active Transport
Mathematical Models and Methods in Applied Sciences, 2016Co-Authors: Harald Garcke, Emanuel Sitka, Kei Fong Lam, Vanessa StylesAbstract:Using basic thermodynamic principles we derive a Cahn–Hilliard–Darcy model for tumour growth including nutrient diffusion, chemotaxis, Active Transport, adhesion, apoptosis and proliferation. In contrast to earlier works, the model is based on a volume-averaged velocity and in particular includes Active Transport mechanisms which ensure thermodynamic consistency. We perform a formally matched asymptotic expansion and develop several sharp interface models. Some of them are classical and some are new which for example include a jump in the nutrient density at the interface. A linear stability analysis for a growing nucleus is performed and in particular the role of the new Active Transport term is analysed. Numerical computations are performed to study the influence of the Active Transport term for specific growth scenarios.
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a cahn hilliard darcy model for tumour growth with chemotaxis and Active Transport
Mathematical Models and Methods in Applied Sciences, 2016Co-Authors: Harald Garcke, Emanuel Sitka, Vanessa StylesAbstract:Using basic thermodynamic principles we derive a Cahn–Hilliard–Darcy model for tumour growth including nutrient diffusion, chemotaxis, Active Transport, adhesion, apoptosis and proliferation. In contrast to earlier works, the model is based on a volume-averaged velocity and in particular includes Active Transport mechanisms which ensure thermodynamic consistency. We perform a formally matched asymptotic expansion and develop several sharp interface models. Some of them are classical and some are new which for example include a jump in the nutrient density at the interface. A linear stability analysis for a growing nucleus is performed and in particular the role of the new Active Transport term is analysed. Numerical computations are performed to study the influence of the Active Transport term for specific growth scenarios.
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a cahn hilliard darcy model for tumour growth with chemotaxis and Active Transport
arXiv: Analysis of PDEs, 2015Co-Authors: Harald Garcke, Emanuel Sitka, Vanessa StylesAbstract:Using basic thermodynamic principles we derive a Cahn--Hilliard--Darcy model for tumour growth including nutrient diffusion, chemotaxis, Active Transport, adhesion, apoptosis and proliferation. The model generalises earlier models and in particular includes Active Transport mechanisms which ensure thermodynamic consistency. We perform a formally matched asymptotic expansion and develop several sharp interface models. Some of them are classical and some are new which for example include a jump in the nutrient density at the interface. A linear stability analysis for a growing nucleus is performed and in particular the role of the new Active Transport term is analysed. Numerical computations are performed to study the influence of the Active Transport term for specific growth scenarios.
James F Sallis - One of the best experts on this subject based on the ideXlab platform.
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where are youth Active roles of proximity Active Transport and built environment
Medicine and Science in Sports and Exercise, 2008Co-Authors: Helene Mollie Grow, Brian E Saelens, Jacqueline Kerr, Nefertiti Durant, Gregory J Norman, James F SallisAbstract:GROW, H. M., B. E. SAELENS, J. KERR, N. H. DURANT, G. J. NORMAN, and J. F. SALLIS. Where Are Youth Active? Roles of Proximity, Active Transport, and Built Environment. Med. Sci. Sports Exerc., Vol. 40, No. 12, pp. 2071–2079, 2008. Purpose: This study examined factors related to two sources of physical activity for youth: Active use of recreation sites and Active Transport to recreation sites. Methods: Parents of children (n = 87) and matched pairs of parents and adolescents (n = 124 pairs) in three US cities reported on youths’ Active use of, proximity to, and walking/biking to 12 recreation sites and on neighborhood walkability and safety. Multivariate regression models evaluated factors associated with youths’ frequent site use and Active Transport to sites. Results: Proximity to the site was associated with frequent use of large parks and public open space. Walking/biking to the site was associated with frequent use of most sites (indoor recreation sites, small and large parks, basketball courts, walking/running tracks, school recreation sites, playgrounds, and public open space). After controlling for proximity and demographic factors, Active Transport to sites remained significantly associated (P G 0.05) with frequent use of four sites for children (indoor recreation, walking/running tracks, school recreation facilities, and public open space) and all but three sites for adolescents (indoor recreation, playfields/courts, and beach/ lake/rivers). Adolescents’ Active Transport to more sites was most positively related to higher perceived traffic safety and to better pedestrian infrastructure and was negatively related to crime threat. Adolescents with driver’s licenses walked/biked to recreation sites less often. Conclusions: Active Transport was strongly associated with the use of multiple recreation sites by children and adolescents, even when accounting for proximity and demographic factors. Adolescents living in neighborhoods with better traffic safety walked/ biked to more recreation sites for physical activity. Findings support the need for built environments and Transportation policies that
Emanuel Sitka - One of the best experts on this subject based on the ideXlab platform.
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A Cahn–Hilliard–Darcy model for tumour growth with chemotaxis and Active Transport
Mathematical Models and Methods in Applied Sciences, 2016Co-Authors: Harald Garcke, Emanuel Sitka, Kei Fong Lam, Vanessa StylesAbstract:Using basic thermodynamic principles we derive a Cahn–Hilliard–Darcy model for tumour growth including nutrient diffusion, chemotaxis, Active Transport, adhesion, apoptosis and proliferation. In contrast to earlier works, the model is based on a volume-averaged velocity and in particular includes Active Transport mechanisms which ensure thermodynamic consistency. We perform a formally matched asymptotic expansion and develop several sharp interface models. Some of them are classical and some are new which for example include a jump in the nutrient density at the interface. A linear stability analysis for a growing nucleus is performed and in particular the role of the new Active Transport term is analysed. Numerical computations are performed to study the influence of the Active Transport term for specific growth scenarios.
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a cahn hilliard darcy model for tumour growth with chemotaxis and Active Transport
Mathematical Models and Methods in Applied Sciences, 2016Co-Authors: Harald Garcke, Emanuel Sitka, Vanessa StylesAbstract:Using basic thermodynamic principles we derive a Cahn–Hilliard–Darcy model for tumour growth including nutrient diffusion, chemotaxis, Active Transport, adhesion, apoptosis and proliferation. In contrast to earlier works, the model is based on a volume-averaged velocity and in particular includes Active Transport mechanisms which ensure thermodynamic consistency. We perform a formally matched asymptotic expansion and develop several sharp interface models. Some of them are classical and some are new which for example include a jump in the nutrient density at the interface. A linear stability analysis for a growing nucleus is performed and in particular the role of the new Active Transport term is analysed. Numerical computations are performed to study the influence of the Active Transport term for specific growth scenarios.
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a cahn hilliard darcy model for tumour growth with chemotaxis and Active Transport
arXiv: Analysis of PDEs, 2015Co-Authors: Harald Garcke, Emanuel Sitka, Vanessa StylesAbstract:Using basic thermodynamic principles we derive a Cahn--Hilliard--Darcy model for tumour growth including nutrient diffusion, chemotaxis, Active Transport, adhesion, apoptosis and proliferation. The model generalises earlier models and in particular includes Active Transport mechanisms which ensure thermodynamic consistency. We perform a formally matched asymptotic expansion and develop several sharp interface models. Some of them are classical and some are new which for example include a jump in the nutrient density at the interface. A linear stability analysis for a growing nucleus is performed and in particular the role of the new Active Transport term is analysed. Numerical computations are performed to study the influence of the Active Transport term for specific growth scenarios.