Investigation of the effects of high pressure pulses on biological samples

The increase in survivability in modern conflict has been accompanied by an increase in casualties with multiple and complex blast injuries which are associated with long term complications such as heterotopic ossification. Improving treatments for these complications requires the development of a c...

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Bibliographic Details
Main Author: Bo, Chiara
Other Authors: Proud, William
Published: Imperial College London 2013
Subjects:
530
Online Access:http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.656387
Description
Summary:The increase in survivability in modern conflict has been accompanied by an increase in casualties with multiple and complex blast injuries which are associated with long term complications such as heterotopic ossification. Improving treatments for these complications requires the development of a cellular and molecular understanding of the effects of blast on live biological samples which in the past has been limited by the lack of experimental capabilities. This thesis describes the development and characterisation of experimental platforms to study the effects of high intensity pressure waves on cells and tissues. A confined Split Hopkinson Pressure Bar (SHPB) system has been developed, allowing cells in suspension or in a monolayer to be subjected to pressure waves in the order of tens of MPa and duration of hundreds of microseconds. The confinement chamber has been designed to enable recovery of the biological samples for cellular and molecular analysis, such as cell survivability, viability, metabolic activity and morphological changes post compression. The SHPB platform, coupled with quasi-static experiments, has also been used to determine stress-strain curves of porcine skin tissue samples under uniaxial compression at low, medium and high strain rates. Three phenomenological models have been used to fit the experimental data at different strain rates and the results compared. The recovered samples have been examined using histological techniques to study morphological changes induced by uniaxial compression. Finally, a shock tube-bio set up has been developed and characterised to replicate primary blast damage on cell monolayers by generating single air blast in the order of kPa and few milliseconds duration. This platform permits investigation of a different pressure-time regime compared to the SHPB system and to analyse post-traumatic changes induced in biological samples. To conclude, different experimental platforms have been successfully developed to study the effects of pressure pulses on biological samples.