Monday 27 February 2017

BioMaths Colloquium - 02/03/2017

BioMaths Colloquium Series - 2016/17

02 March 2017 - 3pm Maths Seminar Room

(room 224 Talbot Building 2nd floor)

Towards a 3D distribution model of drugs in the brain

Dr Vivi Rottschäfer

(Mathematisch Instituut,Leiden University, Netherlands

Our BioMaths Colloquium Series for the winter term continues with a seminar by Dr Vivi Rottschäfer from the Mathematisch Instituut at Leiden University in the Netherlands. Vivi is a mathematician and Associate Professor in the research group Analysis and Dynamical Systems. Her interests are in dynamical systems and partial differential equations with the aim to find novel applications in pharmacology and ecology. Examples include pattern evolution and how phase separation can explain self-organised spatial patterns in ecology.

Development of drugs with adequate action on the brain is highly challenging. Quantitative understanding is needed on the highly complex processes that govern the concentration-profile of a drug, such as transport of the drug from blood to brain and subsequent distribution to the target site. Existing models for prediction of drug distribution and effect consist of systems of ordinary differential equations  to describe the pharmacokinetics of drugs in multiple physiological brain compartments. However, it is important to also take into account local brain distribution, as target expression in the brain can substantially differ between different  regions in the brain.

On the way towards a 3D spatial drug distribution model of the brain, we first developed a 2D model that gives more detailed insight into the change of drug concentration in the brain in both time and space. The model consists of  a system of a partial differential equation and ordinary differential equations  that describe the concentration of free drug in the brain  and the concentrations of free and bound receptors on the surface of the brain cells. In this model we integrate both the drug distribution and target interaction kinetics, to ultimately improve the prediction of drug action in the brain. 

The discussions will continue over biscuits and tea/coffee after the seminar. 
Hope to see many of you!

Tuesday 21 February 2017

BioMaths Colloquium - 24/02/2017

BioMaths Colloquium Series - 2016/17

24 February 2017 - 3pm Maths Seminar Room

(room 224 Talbot Building 2nd floor)

From discrete to continuum models of a multi-cellular system

Dr Philip Murray

(Department of Mathematics,University of Dundee, UK

Our BioMaths Colloquium Series for the winter term continues with a seminar by Dr Philip Murray from the Department of Mathematics at the University of Dundee. Philip is a mathematician with a wide interest especially in biomedical topics, from Tumour Modelling, Somitogenesis and Hair follicle growth patterning, to DNA repair mechanisms, Intestinal crypt modelling, and Discrete to continuum models of cell populations. The latter will be the subject of his talk.

The scale on which a given biological problem is mathematically defined depends on a range of factors (e.g. availability of experimental data and computational tools, preferences of the modeller etc.). Historically, multi-cellular systems were described using continuum models. Amongst the advantages of this approach is the availability of existing mathematical tools that allow one to analyse models and gain qualitative insights from the solutions. 

More recently, discrete cell-based models have been used to study multicellular systems. Amongst their advantages are that they are conceptually easy to communicate and can naturally accommodate features such as heterogeneity and stochasticity.  As these (typically N-body) problems are solved using brute force approaches, it can be difficult to gain qualitative insight from the computed solutions. 

In this talk I will describe how to take the continuum limit of a particular family of discrete cell-based models. By performing a travelling wave analysis on the resultant equations, I will describe interesting features of the underlying simulations and show how they can be qualitatively related to the model parameters.  

The discussions will continue over biscuits and tea/coffee after the seminar. 
Hope to see many of you!

Thursday 16 February 2017

Biosciences Seminar Speaker 16 February 2017

Biosciences Seminar Series - Winter 2017
16 February 2017 - 1pm - Zoology Museum

The effects of oxygen availability and turbulence on water quality in lakes and reservoirs

Dr Lee Bryant

Photo by Marlkolf Zimmer

Our second seminar of the winter term will be presented by Dr Lee Bryant from the Research Unit for Water, Environment and Infrastructure Resilience (WEIR) at Department of Architecture and Civil Engineering at the University of Bath. Lee is interested in biogeochemical cycling in aquatic systems, especially the influence of oxygen cycling and turbulence/aeration, or the mechanisms and consequences of mass transport of nutrients, metals etc. at the water/sediment interface. Her current projects focus on the effects of seasonal algal blooms on marine benthic oxygen dynamics; the geochemical, microbial and hydrologic characteristics of storm runoff loads within an informal settlement; and the influence of bioturbation and respiration on oxygen and trace metal cycling.

Oxygen and mixing conditions in aquatic systems have a significant influence on the biogeochemical cycling of nutrients, metals, and other species at the sediment-water interface; these fluxes often control water quality in lakes and reservoirs.  In an effort to counter problems with decreased water quality stemming from anoxic conditions, engineered techniques such as hypolimnetic oxygenation systems are being used more and more prevalently to increase aquatic oxygen concentrations and reduce concentrations of deleterious soluble species. 

Decreased oxygen levels in oceans are also becoming increasingly problematic due to enhanced anthropogenic effects and global warming. In both freshwater and marine systems, fluxes of oxygen, nutrients, and other chemical species are
From Muller, Bryant et al. 2012 
known to be strongly controlled not only by concentration but also by turbulence such as internal waves; however, hydrodynamics can be highly variable and effects on biogeochemical cycling and corresponding water quality are not currently understood.  

Based on in-situ microprofiler and aquatic eddy correlation measurements, results will be presented from three process studies focusing on (1) the effects of internal waves (e.g., seiches), (2) bioturbation, and (3) engineered hypolimnetic oxygenation / aeration on sediment-water fluxes of oxygen and manganese in lakes and reservoirs.  These studies will be used to highlight the physical and chemical processes controlling biogeochemical cycling and related water quality in aquatic systems.

Hope to see many of you - everyone most welcome to attend!

For the list of forthcoming seminars, see here, and here

Monday 6 February 2017

Biosciences Seminar Speaker 09 February 2017

Biosciences Seminar Series - Winter 2017
09 February 2017 - 1pm - Zoology Museum

Technology for Nature?

Prof Kate Jones

(University College London, UK)

Photo: Kate Jones / Bat Conservation Trust

Our seminar series continues for the winter term with a talk by Prof Kate Jones from the Centre for Biodiversity and Environment at University College London. Kate holds a Chair of Ecology and Biodiversity and leads the biodiversity modelling research group, interested in understanding how biodiversity is maintained and conserved globally. Her research revolves around three themes: understanding biodiversity patterns, modelling ecological processes, and technology for nature, the latter of which will be the topic of this week's seminar. 

For example, Kate and her group aim to understand how evolutionary processes produce past and present global biodiversity patterns, or find ways to predict the impacts of global change. The latter includes quantifying how biodiversity loss impacts the emergence and transmission of diseases, incl. human emerging infectious diseases. To do so, Kate tries to find new technological solutions to improve current biodiversity monitoring and to engage citizen scientists. 

Above all, however, a unifying theme is certainly an inordinate fondness for bats.

Wild nature and natural ecosystems are declining rapidly as humans use more of the earth’s resources and change climate patterns. Thanks to the growth of networks of citizen scientists and new sensor technology such as animal movement tags, camera traps and passive acoustic sensors, scientists studying the impact of anthropogenic change now have access to huge amounts of data about our changing environment and declining wildlife populations. 

Professor Kate Jones will review some of the latest advances in sensors used to monitor wildlife and machine learning approaches to analyse the big biodiversity data gathered, including her work on acoustic monitoring bat populations. Kate argues that although technological advances have undoubtedly contributed to the over-exploitation of natural resources and decline of wild nature, technology can also help us to better understand the natural world and to further engage people with their environment.

Hope to see many of you - everyone most welcome to attend!

For the list of forthcoming seminars, see here, and here