m

Documents  92C15 | enregistrements trouvés : 12

O
     

-A +A

P Q

Déposez votre fichier ici pour le déplacer vers cet enregistrement.

Research talks;Analysis and its Applications;Dynamical Systems and Ordinary Differential Equations;Partial Differential Equations

We introduce and analyze a mathematical model for the regeneration of planarian flatworms. This system of differential equations incorporates dynamics of head and tail cells which express positional control genes that in turn translate into localized signals that guide stem cell differentiation. Orientation and positional information is encoded in the dynamics of a long range wnt-related signaling gradient.
We motivate our model in relation to experimental data and demonstrate how it correctly reproduces cut and graft experiments. In particular, our system improves on previous models by preserving polarity in regeneration, over orders of magnitude in body size during cutting experiments and growth phases. Our model relies on tristability in cell density dynamics, between head, trunk, and tail. In addition, key to polarity preservation in regeneration, our system includes sensitivity of cell differentiation to gradients of wnt-related signals measured relative to the tissue surface. This process is particularly relevant in a small tissue layer close to wounds during their healing, and modeled here in a robust fashion through dynamic boundary conditions.
We introduce and analyze a mathematical model for the regeneration of planarian flatworms. This system of differential equations incorporates dynamics of head and tail cells which express positional control genes that in turn translate into localized signals that guide stem cell differentiation. Orientation and positional information is encoded in the dynamics of a long range wnt-related signaling gradient.
We motivate our model in relation to ...

92C15 ; 35B36 ; 35Q92 ; 37N25 ; 35K40

... Lire [+]

Déposez votre fichier ici pour le déplacer vers cet enregistrement.


ISBN 978-3-540-66522-9

Lecture notes in mathematics , 1714

Localisation : Collection 1er étage

EDP # biodynamique # biomathématique # biomodélisation # biophysique # dynamique des populations # fonction de Lyapunov # modèle dans des espaces discrètes # modélisation stochastique # problème de limite # problème initial linéaire # problème spectrale # réaction # système aléatoire # système de transport # équation différentielle ordinaire

34Cxx ; 34Dxx ; 35Bxx ; 35Kxx ; 60Hxx ; 60Kxx ; 92-06 ; 92Bxx ; 92C15 ; 92Dxx

... Lire [+]

Déposez votre fichier ici pour le déplacer vers cet enregistrement.

- ix; 382 p.
ISBN 978-0-8218-8737-0

Contemporary mathematics , 0586

Localisation : Collection 1er étage

analyse numérique # mathématiques appliquées # homogénisation # diffraction

65N55 ; 76M50 ; 78A45 ; 81V55 ; 49N45 ; 68W25 ; 78M40 ; 92C15 ; 65-06 ; 65Z05 ; 00A69 ; 00A79 ; 00B25

... Lire [+]

Déposez votre fichier ici pour le déplacer vers cet enregistrement.

Research talks;Mathematics in Science and Technology

92C37 ; 92C20 ; 92C50 ; 92C15

... Lire [+]

Déposez votre fichier ici pour le déplacer vers cet enregistrement.

Research talks;Dynamical Systems and Ordinary Differential Equations;Partial Differential Equations

Macrophages are a type of immune cells that can be present in high numbers in some solid tumours. The heterogeneity of macrophage populations (with the anti-tumour M1 cells and thepro-tumour M2 cells being the two extreme phenotypes) has led to difficulties in understanding the innate immune responses to tumours. Here we introduce a class of mathematical models for the interactions between a population of tumour-associated macrophages (structured by their phenotype) and a population of cancer cells (that could be structured by their mutation status). We then use this class of models to confirm that the M1 cells kill tumours, while the M2 cells can lead to tumour growth. In addition, we show that macrophages with mixed phenotypes can contribute to either tumour growth or tumour decay. We also show that tumour dormancy is associated not only with an increased heterogeneity of cancer population, but also with an increased heterogeneity of macrophage population. Macrophages are a type of immune cells that can be present in high numbers in some solid tumours. The heterogeneity of macrophage populations (with the anti-tumour M1 cells and thepro-tumour M2 cells being the two extreme phenotypes) has led to difficulties in understanding the innate immune responses to tumours. Here we introduce a class of mathematical models for the interactions between a population of tumour-associated macrophages (...

92C15 ; 35L60 ; 92C42

... Lire [+]

Déposez votre fichier ici pour le déplacer vers cet enregistrement.

Research talks;Dynamical Systems and Ordinary Differential Equations;Mathematics in Science and Technology

Oxygen is essential for burning food and generate energy, but may become limiting for aquatic organisms that rely on gas exchange under water. This is because breathing under water is challenging: the diffusion of oxygen is orders of magnitude lower in water than in air, while the higher density and viscosity of water greatly enhance the cost of breathing. Given that oxygen may be also be a limiting resource, respiration physiology may be relevant to understand energy budgets in aquatic ectotherms.
Traditionally, respiration physiology has focused on the benefits of extracting sufficient amounts of oxygen and thus prevent asphyxiation. However, breathing oxygen is intrinsically dangerous: while a shortage of oxygen quickly leads to asphyxiation, too much oxygen is toxic. Therefore, the ability to regulate oxygen consumption rates (i.e. respiratory control) is at a premium; good respiratory control will enable ectotherms to balance oxygen toxicity against the risk of asphyxiation across a wide range of temperatures.
In this presentation I will focus on the effects of body size and temperature on this balancing act with regard to oxygen uptake and consumption. Body size is intimately tied to oxygen budgets and hence energy budgets through size related changes in oxygen requirements and respiratory surfaces. Furthermore, a larger body size may represent a respiratory advantage that helps to overcome viscosity. Given that viscous forces are larger in cold water, this respiratory advantage represents a novel explanation for the pattern of larger body sizes in cold water, with polar gigantism as the extreme manifestation.
Temperature is also intimately tied to oxygen budgets and hence energy budgets through thermal controls on metabolism and temperature related changes in the availability of dissolved oxygen (notably diffusivity, viscosity and solubility). Thus, differences in temperatures may act more strongly on ectotherms that rely on aquatic rather than on aerial gas exchange. Comparing four different insect orders, I demonstrate that thermal tolerance is indeed affected more by the prevalent oxygen conditions in species with poor respiration control. In conclusion, the ability to regulate gas exchange (i.e. respiratory control) is thus a key attribute of species that helps to explain thermal responses from an oxygen perspective.
Oxygen is essential for burning food and generate energy, but may become limiting for aquatic organisms that rely on gas exchange under water. This is because breathing under water is challenging: the diffusion of oxygen is orders of magnitude lower in water than in air, while the higher density and viscosity of water greatly enhance the cost of breathing. Given that oxygen may be also be a limiting resource, respiration physiology may be ...

92D25 ; 92D50 ; 92C15 ; 92C30

... Lire [+]

Déposez votre fichier ici pour le déplacer vers cet enregistrement.

- 811 p.
ISBN 978-0-387-95228-4

Interdisciplinary applied mathematics , 0018

Localisation : Ouvrage RdC (MURR)

biologie # biomathématique # biologie du développement # mouvement cellulaire # morphogénèse # épidémiologie # modèle spacial # médecine # équation de réaction-diffusion # modélisation mathématique

92B05 ; 92-01 ; 92C15 ; 92C17

... Lire [+]

Déposez votre fichier ici pour le déplacer vers cet enregistrement.

- vii; 249 p.
ISBN 978-1-4704-1080-3

Courant Lecture Notes , 0026

Localisation : Ouvrage RdC (PERC)

biomathématiques # biologie du développement # théorie des catastrophes # formation de motif # morphogenèse # chimiotaxie # prolifération de cellules # formation de somites # embryon d'insecte

92C10 ; 92C15 ; 92C17 ; 92C45 ; 92B05

... Lire [+]

Déposez votre fichier ici pour le déplacer vers cet enregistrement.

- 131 p.
ISBN 978-0-444-88486-2

Localisation : Oeuvres complètes RdC (SAUN)

base chimique de la morphogénèse # biologie # développement de la marguerite # modèles mathématiques # morphogénèse des plantes # phyllotoxie # théorie de la réaction de diffusion de la morphogénèse dans # théorie morphogène de la phyllotoxie # Saunders # oeuvres complètes

92-XX ; 92C15 ; 92Exx

... Lire [+]

Déposez votre fichier ici pour le déplacer vers cet enregistrement.

- x; 130 p.
ISBN 978-3-03719-172-9

EMS series of lectures in mathematics

Localisation : Ouvrage RdC (TRIE)

espace de fonctions de Besov-Sobolev # chimiotaxie # hydrodynamique # équation de chaleur # équation de Keller-Segel # équation de Navier-Stokes

35-02 ; 46-02 ; 76-02 ; 92-02 ; 35K05 ; 35Q30 ; 35Q92 ; 42B35 ; 46E35 ; 76D05 ; 92C15 ; 92C17

... Lire [+]

Déposez votre fichier ici pour le déplacer vers cet enregistrement.

- 246 p.
ISBN 978-3-540-29162-6

Lecture notes in mathematics , 1872

Localisation : Collection 1er étage

mathématiques appliquées à la biologie # cycle cellulaire # prolifération cellulaire # canar # modélisation # tuneur # chimiothérapie

34C60 ; 35G25 ; 35G30 ; 35M10 ; 35Q80 ; 35R30 ; 35R35 ; 49K15 ; 92C15 ; 92C17 ; 92C37 ; 92C50 ; 93C15

... Lire [+]

Déposez votre fichier ici pour le déplacer vers cet enregistrement.

Localisation : Ouvrage RdC (C)

conseil génétique # diagnostic prénatal # enfant malformé # modèle additif généralisé # régression logistique # translocation réciproque

62P10 ; 92C15 ; 92D10

... Lire [+]

Z