Characterisation of the mechanobiology and definition of a clinically relevant failure criterion

Faculty

School of Mechanical and Design Engineering

This project is now closed. The details below are for information purposes only. View our current projects here.
 

Applications are invited for a fully-funded 3-year PhD to commence in October 2019. The PhD project will be based in the School of Mechanical and Design Engineering and will be supervised by Dr Martino Pani, Dr Andrea Bucchi and Professor Jan Shute.

Successful applicants will receive a bursary to cover tuition fees for three years and a stipend in line with the RCUK rate (£15,009 for 2019/2020). The Faculty of Technology may fund project costs/consumables up to £1,500 p.a.

A comprehensive understanding of the mechanical behaviour of human soft tissues has a great clinical importance and can improve the medical treatment of a number of critical cardiovascular diseases, such as the rupture of abdominal aortic aneurysm (AAA).

An aneurysm is a permanent and irreversible localized dilatation of blood vessels, usually in a saccular or fusiform shape. The AAA is ranked as the 15th most frequent cause of death in individuals aged over 60 and each year, it's responsible for 8000 fatalities within the UK alone.

A major cause for concern is the asymptomatic development of AAA. If undetected, an aneurysm continues to grow silently over the years until rupture. The rupture is an event that leads to death within hours in 65-85% of cases, in the absence of any emergency surgery treatment.

The rupture and damage mechanisms in soft tissues are a poorly understood and barely investigated topic. For this reason, most of the analysis and models which consider tissue failure assume failure criteria derived from ‘classical’ materials such as metals.

These theoretical models are generally informed by a planar biaxial extension where the tissue is held in place via the use of hooks. This established test has some intrinsic limitations: the material will always fail in the neighborhood of the hooks.

This failure is fictitious and it is not indicative of the tissue strength. To rectify this issue, we propose to use an inflation test, where the tissue is stretched under the action of a pressurized fluid (e.g. air or water), instigating the failure in a region away from the boundaries. Our research group has realized a preliminary design of such a device, embedding a multi-camera stereo-vision to accurately capture the out of plane deformations.

The aim of the project is to refine the actual device, tailoring it to test different soft tissue (e.g. aortic valve, blood vessels, etc.) to better characterise and understand soft tissue failure mechanisms.

Second harmonic imaging microscopy will provide details regarding the tissue microstructure, and insights about the damaged areas. This will lead to a structurally-based continuum mechanics model addressing tissue damage and failure mode.

The project will be a joint collaboration between the CERL (Cardiovascular Engineering Research Laboratory) at the School of Mechanical and Design Engineering and the School of Pharmacy and Biomedical Sciences at the University of Portsmouth. External collaboration with local NHS Trust Hospitals will equip the research team with the possibility to perform tests on human tissue.

Entry requirements

How to apply

Please contact Dr Martino Pani (martino.pani@port.ac.uk) or Dr Andrea Bucchi (andrea.bucchi@port.ac.uk) to discuss your interest before you apply, quoting the project code.

When you are ready to apply, you can use our online application form and select ‘Mechanical and Design Engineering’ as the subject area. Make sure you submit a personal statement, proof of your degrees and grades, details of two referees, proof of your English language proficiency and an up-to-date CV.

Our ‘How to Apply’ page offers further guidance on the PhD application process.

Please note, to be considered for this funded PhD opportunity you must quote project code ENGN4640219 when applying.