Eoin Parle - E-Portfolio
Lecturer in Mechanical Engineering
Senior Research Engineer
MET Gateway Research Centre
Galway-Mayo Institute of Technology (GMIT)
Galway, Ireland
Media
Micro Monsters 3D with David Attenborough (click for trailer)
In 2014, I had the pleasure of being flown to London by SkyTV to film some of my experiments into the material properties of insect cuticle. Unfortunately, we did not make the final edit, but the experience was very enjoyable nonetheless. Click the above link to see a trailer and "behind the scenes" footage of this fascinating program.
Mechanobiology:
Details on the highly interesting and innovative research carried out by my lab group in NUI Galway under the supervision of Dr. Laoise McNamara into bone tissue, cell mechanobiology and mechanotransduction, multiphysics and multiscale modelling, tissue regeneration and medical device design.
Insect Cuticle:
My most recent paper on insect injury repair has received publicity widely:
Society for Science (Science website for students based in Washington D.C)
Other publications have similarly received some notice:
Published Papers
Polak-Kraśnaa K, Parle, E., et al., (2020)
Acta Biomaterialia - In Press
This study presents a systematic evaluation of the physical, thermal and mechanical performance of medical-grade semi-crystalline PLLA undergoing thermally-accelerated degradation. Samples were immersed in phosphate-buffered saline solution at 50°C for 112 days and mass loss, molecular weight, thermal properties, percent crystallinity, FTIR and Raman spectra, tensile elastic modulus, yield stress and failure stress/strain were evaluated at consecutive time points.
Journal of Bone and Mineral Research Plus Vol 4: 2
The increase in fracture risk associated with osteoporosis is well known and well researched. Less so, is the increase in fracture risk associated with diabetes. In this study I investigated human femoral head trabecular bone from osteoarthritic, osteoporotic, and type 2 diabetic patients to shed new light on some of the underlying biomechanical reasons for these increased fracture risks. This was undertaken under the supervision of Prof. Laoise McNamara, NUI Galway as part of my 2 year IRC postdoctoral research fellowship.
O'Sullivan LM, Allison H, Parle E, Schiavi J, McNamara LM (2019)
Osteoporosis International doi: 10.1007/s00198-019-05239-5
This study delineates the time sequence of changes in bone tissue mineralisation in ovariectomised rats. We report that changes in bone mineral distribution arise secondary to the initial rapid bone loss but coincide with trabecular thickening. We propose that these changes compensate for elevated stresses in remaining trabeculae after bone resorption
Amin B., Shahz A., Farin L., Parle E., McNamara L., O'Halloran M., Elahi MA., (2019)
Dielectric characterization of diseased human trabecular bones at microwave frequency
Medical Engineering and Physics https://doi.org/10.1016/j.medengphy.2020.01.014
The objective of this study is to determine whether in vitro dielectric properties of human trabecular bones, can distinguish between osteoporotic and osteoarthritis patients’ bone samples. Specifically this study enlightens intra-patient variation of trabecular bone microarchitecture and dielectric properties, inter-disease comparison of bone dielectric properties, and finally establishes the correlation to traditional bone histomorphometry parameter (bone volume fraction) for diseased bone tissue
Parle, E., Dirks, J-H, and Taylor, D. (2017)
Arthropod Structure and Development, Vol 46: 1, 49-55
This review article summarizes what is known thus far relating to the mechanical properties of insect cuticle, and what factors can affect these properties. Mechanisms for damage (such as fatigue) are analysed, as is the insects ability to recover from this damage. Cuticle is compared to bone and wood, and the possibility of an active feedback mechanism in insect cuticle such as that of modelling or remodelling present in bone is also analysed. New conclusions and possibilities for future research are outlined.
Parle, E. and Taylor, D. (2017)
The Effect of Aging on the Mechanical Behaviour of Cuticle in the Locust Schistocerca gregaria
Journal of the Mechanical Behaviour of Biomedical Materials. doi: 10.1016/j.jmbbm.2017.02.008
The effect of natural growth of the insect cuticle is analysed in terms of its contribution to strength, stiffness, failure mode and geometry of the tibia structure. Two distinct growth phases were identified. In the first 3 weeks post-moult, an adult insect shows a rapid increase in thickness, which is matched by an increase in strength and stiffness. Initially, the leg, being quite thin is prone to failure by buckling. Once the leg enters the "mature" phase, strength and stiffness remain almost constant. These legs fail due to reaching the material strength during testing, something which could not be increased by adding more material (hence the slower deposition rates). It is possible that some feedback mechanism may be present in the cuticle to account for these two different growth phases.
Parle, E., Dirks, J-H, and Taylor, D. (2016)
Journal for the Royal Society Interface 13: 20150984.
This paper examines the wound healing processes present in insects and its effectiveness at restoring the original mechanical properties (strength, stiffness and toughness) to the injured cuticle. It is the first biomechanical analysis of injury repair in insects, and received wide publicity. Targetted cuticle deposition to the wounded area is triggered by the injury, and can restore up to 66% of the original strength of the leg, hindering crack growth by over 150% more than an unhealed leg.
Parle, E., Herbaj, S., Sheils, F., Larmon, H., and Taylor, D. (2015)
Buckling Failures in Insect Legs
Bioinspiration and Biomimetics 11, 016003 (doi: 10.1088/1748-3190/11/1/016003)
Investigates the phenomenon of local buckling failure seen during testing insect legs from different species (Loust hind-leg and mid-leg, American cockroach, Death's Head cockroach, Stick Insect and Honey Bee). We use mathematical models and 3D ANSYS models to predict the buckling strength of each leg. Anatomical variations and customisations seen in different species are examined in terms of their overall contribution to the strength of the legs.
Parle, E., Larmon, H., and Taylor, D. (2016)
Biomechanical Factors in the adaptations of insect tibia cuticle
PLoS ONE 11(8): e0159262. doi:10.1371/journal.pone.0159262
Investigates how the material properties (stiffness, strength and geometry) of insect tibia cuticle vary from insect to insect, and indeed from one leg to another on the same insect. Does the function of the leg determine these properties? The forces experienced in vivo, and a factor of safety for each tibia shows how close the insect operates to its structural limit, and how evolution has strived to optimize each leg for its individual purpose.
Parle, E. and Taylor D. (2014)
Self-Healing Properties of Insect Cuticle
Journal of Postgraduate Research, TCD, Volume 12, 90-111
Investigates insect cuticle's ability to self-repair after cyclic loads are applied to living locust tibiae, and the absence of such recovery in cuticle that is removed from the insect.
Dirks, J-H., Parle, E. and Taylor, D. (2013)
Journal of Experimental Biology 216, 1924-1927
The first ever publication of the fatigue properties of Insect Cuticle (hind tibiae and hind wings)
Conferences
BINI (Bioengineering in Ireland) 2019
Castletroy House Hotel, Limerick
- Characterisation of accelerated in-vitro degradation induced alterations in mechanical and material properties of medical PLLA
WCB (World Congress of Biomechanics) 2018
The Convention Centre, Dublin
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Osteoporosis and Diabetes increase mineral heterogeneity in human femoral heads
EORS (European Orthopaedic Research Society) 2018
Radisson Hotel, Galway
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Mineral heterogeneity is altered in the femoral heads of osteoporotic and diabetic human patients
ORS (Orthopaedic Research Society) 2018
New Orleans, USA
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Mineral heterogeneity is altered in the femoral heads of osteoporotic and diabetic human patients
BINI (Bioengineering in Ireland) 2018
Johnstown House Hotel, Kildare
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Mineral heterogeneity is altered in the femoral heads of osteoporotic and diabetic human patients
Irish Polymers and Materials Conference 2017
Additive Manufacturing of Diamond Cutting Tools-Pushing the boundaries of 3D Printing.
BINI (Bioengineering in Ireland) 2016
Salthill Hotel, Galway, Ireland
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Bridging the gap: wound healing in insects restores mechanical strength by targeted cuticle deposition
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Age-related changes in the stiffness of insect cuticle.
Joint Symposium of IMS (Irish Mechanics Society) and ISSEC (Irish Society for Scientific & Engineering Computation) 2015
University College Dublin
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Invited speaker: Insect cuticle growth rates: their purpose and effect on tibia structural properties in the desert locust.
ICOMBT (International Conference of Mechanics of Biomaterials and Tissues) 2015
Waikoloa, Hawaii, USA
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How cuticle growth affects the mechanical properties and failure mode of an insect's tibia.
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Measuring locust tibia cuticle layers to study mechanical properties and repair.
SEB (Society of Experimental Biology) 2015
Clarion Congress Hotel, Prague, Czech Republic
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Biomechanical factors in the evolution of insect tibia cuticle.
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Buckling failures in insect legs.
WCB (World Congress of Biomechanics) 2014
Hynes Convention Centre, Boston, USA
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Self-Healing Properties of Insect Cuticle
SEB (Society of Experimental Biology) 2014
Manchester University, Manchester, UK
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Self-Healing Properties of Insect Cuticle
Sir Bernard Crossland Symposium, 2014
NUIG, Galway, Ireland
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Self-Healing Properties of Insect Cuticle
ICOMBT (International Conference of Mechanics of Biomaterials and Tissues) 2013
Sitges, Barcelona, Spain
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Fatigue Properties of Insect Cuticle.
SEB (Society of Experimental Biology) 2013
Valencia Conference Centre, Valencia, Spain
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Fatigue Properties of Insect Cuticle.
BINI (Bioengineering in Ireland) 2013
Johnstown, Co. Meath, Ireland
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Fatigue Properties of Insect Cuticle.