Dr. Kevin O'Kelly

Summary

Neural electrodes are devices implanted into the brain for either recording neural impulses or stimulating neurons with electrical impulses from an external source. Electrodes can be for acute (short term) or chronic (long term) recording or stimulation. An important consideration is the response of living tissue to electrode implantation. It is this tissue response that causes electrodes to fail by encapsulating the electrode in a protective layer called the glial scar. The observed tissue response is caused by a combination of the traumatic injury of electrode insertion and the persistent presence of a foreign body in the neural tissue. A scientific need exists for active implanted electrodes that improve on the functionality of existing technologies. This project will investigate two different strategies: (1) minimise the size of the electrode to diameters of <25 μm. It is hypothesized that by constructing a micrometer-size device, reduction of initial swelling and glial scar formation can be achieved. Electrodes of this size will require novel insertion and fixation methods. (2) develop electrodes that suppress activity in specific areas of the brain by localized cooling. Current techniques involve electrically "overstimulating" these areas to suppress activity. New developments have shown that cooling these areas produces a similar effect without the accompanying complications. The purpose of this project is to develop clinically relevant electrode systems that are commercially viable.

Funding Agency

HEA

Programme

PRTLI5

Project Type

Research

Summary

This project will build on previous fundamental research developing a novel ceramic scaffold with a tri-modal pore structure. It will advance the results from in vitro testing to investigate the efficacy for providing appropriate nutrient and growth factor environments to support proliferation and differentiation of seeded mesenchymal stem cells in a diffusion environment similar to in vivo conditions. It will also optimise the manufacturing parameters with a view to commercialisation and larger scale manufacturing, focusing initially on the dental implant applications. The project addresses the limitations of bone grafts scaffolds optimised for perfusion bio-reactors which fail to provide a suitable environment throughout the volume for in-vivo applications, forming bone only in the outer 250μm - 500μm. It has been established that supply of nutrient molecules and removal of metabolic waste products are crucial to promote tissue formation. Overcoming the mass transport limitations occuring in vivo represents the most significant challenges for bone tissue scaffolds.

Funding Agency

HEA

Programme

PRTLI5

Project Type

Research

Summary

In this project we will describe how the addition of two friction modifiers change properties of ZDDP antiwear films. Surfaces will be analysed with profilometry, SEM and XPS. I think this paper will cover the chemical composition of the layers. Fresh and aged oils will be used. There is also a trend in the of the friction tests that one FM work better in boundary lubrication region while the other in mixed lubrication. Will perform tests at different speeds in the wear test to see if the same trends are observed there. If so the I might use SEM to see if there is any changes in chemical nature of the films. Also samples with both FMs will be tested as this might show that the blend is then working in "all" regions. The influence of friction modifiers on the antiwear film - effect of aged oils II - will also be investigated using nanoindention and AFM to analyse the surfaces. This work will then cover the mechanical properties of the film as well as distribution and local friction and finally the influence of roughness.

Funding Agency

EU Framework 6

Programme

Marie Curie Fellowship

Project Type

Applied research

Person Months

36

Summary

The work will develop fracture toughness models relevant to small scale micro electro-mechanical systems (MEMS) by quantifying the the interaction between microstructure and fracture process in real ceramic systems. This will have significant benefit for design in MEMS applications. This work proposes to develop a model for nano-indentation fracture based on the 3D morphology of cracks and the stress fields arising in materials of varying microstructural complexity. This work will carry out experimental and numerical work to investigate the stress fields and cracks generated by different indenter geometries in materials of varying microstructural complexity. The approach is based on preliminary work carried out independently by the TCD and the UNSW groups as well as collaborative work carried out while Dr. O'Kelly was a Visiting Resarch Fellow in UNSW.

Funding Agency

SFI

Programme

Research Frontiers Programme

Project Type

Fundamental research

Person Months

72

Summary

The work programma assessed the effects of osteoporosis, drug-treatment, and normal ageing on the mechanical integrity and architecture of bone. It involved a 52 week longitudinal study of Wistar rats.

Funding Agency

EU

Programme

5th Framework