Forthcoming Seminars

Please note that the list below only shows forthcoming events, which may not include regular events that have not yet been entered for the forthcoming term. Please see the past events page for a list of all seminar series that the department has on offer.

Past events in this series
Today
11:00
to
25 September 2019
16:00
Various Speakers

Further Information: 

In vitro tissue engineering (TE) aims to create functional tissue and organ samples external to the body to replace damaged or diseased tissues and organs. By using cells (e.g. autologous or allogenic) in combination with natural or synthetic biomaterial scaffolds and biochemical factors, tissueengineered products have many advantages over traditional approaches such as donor tissue and organ transplantation that can elicit an adverse immune response. The development of the growing tissue construct, the combination of scaffold, cells, extracellular matrix (ECM) and biochemical factors, often occurs within a bioreactor that enables precise control of the bio-mechanochemical environment experienced by the cells within the growing construct.


This is particularly important in the development of mechanosensitive tissues, such as bone. Successfully engineering tissues in vitro has required the development of new smart biomaterials, new tissue growth strategies involving defined biological cues, and novel and bespoke bioreactor environments for growing tissue under physiological mechanical conditions. To date, only simple avascular tissues have been successfully generated to a standard where they can be used in a clinical setting, and research into methods for improving tissue viability is essential.


In TE systems, fluid and solid mechanics are used to provide mechanical load (e.g. via fluid shear, elastic deformation) to mechanosensitive tissues such as bone and vasculature, and a key challenge is to recreate the mechanical environment within the bioreactor system that is unique to the tissue under consideration. The fluid flows and solid deformations are intricate, requiring an understanding of novel fluid-structure interactions between the fluid flows, the cells and their ECM, and the (often deformable) biomaterial.  Furthermore, successful tissue growth in bioreactor systems relies on appropriate solute delivery to and waste-product removal from the cells in the tissue construct. To promote transport (without recourse to agitation methods that can be damaging to cells in a tissue-engineering setting), fluid flows are exploited to enhance transport by advection. 

In this colloquium, we will present state-of-the-art theoretical and experimental fluid and solid mechanics for TE, and explore the transformative potential of combined quantitative theoretical and experimental approaches to inform in vitro TE protocols. The theoretical models will be validated via detailed comparison of the theoretical model predictions with quantitative data obtained from state-of-the art biomechanics experiments. The hybrid approach of combining the resulting insights from the validated theoretical models with in vitro TE experiments can then be used to inform bioreactor and smart biomaterial design for TE strategies, with the aim of improving tissue viability.

Delegates are drawn from the theoretical and experimental fluid and solid mechanics communities. To ensure the focus remains applicable to the TE challenges, we have invited leading figures from the TE community, which will also facilitate new opportunities for interdisciplinary collaboration.

Abstract

Here is the scientific program.

 

Keynote speakers:

Roger Kamm, Cecil and Ida Green Distinguished Professor of Biological and Mechanical Engineering, MIT

Alicia El Haj,  Interdisciplinary Chair of Cell Engineering, Healthcare Technology Institute, University of Birmingham

 

Invited speakers (confirmed to date):

Davide Ambrosi, Politecnico di Torino, Italy

Anthony Callanan, University of Edinburgh, UK

Ruth Cameron, University of Cambridge, UK

Sonia Contera, University of Oxford, UK

Linda Cummings, New Jersey Institute of Technology, USA

Mohit Dalwadi, University of Oxford, UK

John Dunlop, University of Salzburg, Austria

John King, Nottingham, UK

Nati Korin, Technion, Israel

Catriona Lally, Trinity College Dublin, Ireland

Sandra Loerakker, TU Eindhoven, Netherlands

Ivan Martin, University of Basel, Switzerland

Scott McCue, Queensland University of Technology, Australia

Pierre-Alexis Mouthuy, University of Oxford, UK

Tom Mullin,  University of Oxford, UK

Ramin Nasehi, Politecnico di Milano, Italy

Reuben O'Dea, University of Nottingham, UK

James Oliver, University of Oxford, UK

Ioannis Papantoniou, KU Leuven, Belgium

Ansgar Petersen, Julius Wolf Institute Berlin, Germany

Luigi Preziosi, Politecnico di Torino, Italy

Rebecca Shipley, University College London, UK

Barbara Wagner, Weierstrass Institute for Applied Analysis and Stochastics, Berlin

Cathy Ye, Oxford University, UK

Feihu Zhao, TU Eindhoven, Netherlands

Tomorrow
12:00
Lionel Houssou
Abstract

In an increasingly urbanized world, where cities are changing continuously, it is essential for policy makers to have access to regularly updated decision-making tools for an effective management of urban areas. An example of these tools is the delineation of cities into functional areas which provides knowledge on high spatial interaction zones and their socioeconomic composition. In this paper, we presented a method for the structural analysis of a city, specifically for the determination of its functional areas, based on communities detection in graphs. The nodes of the graph correspond to geographical units resulting from a cartographic division of the city according to the road network. The edges are weighted using a Gaussian distance-decay function and the amount of spatial interactions between nodes. Our approach optimize the modularity to ensure that the functional areas detected have strong interactions within their borders but lower interactions outside. Moreover, it leverages on POIs' entropy to maintain a good socioeconomic heterogeneity in the detected areas. We conducted experiments using taxi trips and POIs datasets from the city of Porto, as a study case. Trough those experiments, we demonstrate the ability of our method to portray functional areas while including spatial and socioeconomic dynamics.
 

Tomorrow
14:15
Adam Brown
Abstract

In 1985, McDowell introduced a family of parabolically induced Whittaker modules over a complex semisimple Lie algebra, which includes both Verma modules and the nondegenerate Whittaker modules studied by Kostant. Many classical results for Verma modules and the Bernstein--Gelfand--Gelfand category O have been generalized to the category of Whittaker modules introduced by Milicic--Soergel, including the classification of irreducible objects and the Kazhdan--Lusztig conjectures. Contravariant forms on Verma modules are unique up to scaling and play a key role in the definition of the Jantzen filtration. In this talk I will discuss a classification of contravariant forms on parabolically induced Whittaker modules. In a recent result, joint with Anna Romanov, we show that the dimension of the space of contravariant forms on a parabolically induced Whittaker module is given by the cardinality of a Weyl group. This result illustrates a divergence from classical results for Verma modules, and gives insight to two significant open problems in the theory of Whittaker modules: the Jantzen conjecture and the absence of an algebraic definition of duality.

7 October 2019
15:45
Emily Stark
Abstract

The relationship between the large-scale geometry of a group and its algebraic structure can be studied via three notions: a group's quasi-isometry class, a group's abstract commensurability class, and geometric actions on proper geodesic metric spaces. A common model geometry for groups G and G' is a proper geodesic metric space on which G and G' act geometrically. A group G is action rigid if every group G' that has a common model geometry with G is abstractly commensurable to G. For example, a closed hyperbolic n-manifold group is not action rigid for all n at least three. In contrast, we show that free products of closed hyperbolic manifold groups are action rigid. Consequently, we obtain the first examples of Gromov hyperbolic groups that are quasi-isometric but do not virtually have a common model geometry. This is joint work with Daniel Woodhouse.

8 October 2019
12:00
Marya Bazzi
Abstract

Multilayer networks are a way to represent dependent connectivity patterns — e.g., time-dependence, multiple types of interactions, or both — that arise in many applications and which are difficult to incorporate into standard network representations. In the study of multilayer networks, it is important to investigate mesoscale (i.e., intermediate-scale) structures, such as communities, to discover features that lie between the microscale and the macroscale. We introduce a framework for the construction of generative models for mesoscale structure in multilayer networks.  We model dependency at the level of partitions rather than with respect to edges, and treat the process of generating a multilayer partition separately from the process of generating edges for a given multilayer partition. Our framework can admit many features of empirical multilayer networks and explicitly incorporates a user-specified interlayer dependency structure. We discuss the parameters and some properties of our framework, and illustrate an example of its use with benchmark models for multilayer community-detection tools. 

 

14 October 2019
14:15
Tim Buttsworth

Further Information: 

A Ricci iteration is a sequence of Riemannian metrics on a manifold such that every metric in the sequence is equal to the Ricci curvature of the next metric. These sequences of metrics were introduced by Rubinstein to provide a discretisation of the Ricci flow. In this talk, I will discuss the relationship between the Ricci iteration and the Ricci flow. I will also describe a recent result concerning the existence and convergence of Ricci iterations close to certain Einstein metrics. (Joint work with Max Hallgren)

  • Geometry and Analysis Seminar

Pages

Add to My Calendar