Guy K. German
Associate Professor/Graduate Program Director
Biomedical Engineering
Background
Research Focus
The multiscale mechanics and failure of heterogeneous tissues, the effect of cleansing and cosmetics on tissue mechanics, the mechanics of shaving, the mechanics of skin disorders and methods to alleviate symptoms, encapsulation and assembly of colloidal particles for biomedical applications, interfacial phenomena.
Our research is focused on understanding and controlling soft matter for use in biomedical applications. The term 'soft matter' not only encompasses a broad range of diverse engineered materials such as gels, pastes and emulsions but also many biological tissues. Using both computational and experimental approaches, such as traction force microscopy, we probe the complex dynamics, structure and mechanics of soft materials over a broad range of length scales.
Multi-scale mechanics of heterogeneous tissues
It is commonly assumed that tissues are homogeneous in composition, however they exhibit striking heterogeneities across many length scales, ranging from the cellular to the macroscopic. We are exploring the multi-scale mechanics of tissues in order to better understand their heterogeneous nature, response to applied strains and failure mechanics. We also explore the mechanics of shaving, the onset and alleviation of skin disorders and the effect of cosmetic treatments on the material properties, drying behavior and physiology of tissues. This research has relevance to fundamental skin physics, dermatology and the cosmetics industry.
Colloidal encapsulation
Like surfactants, colloidal particles adsorbed to fluid interfaces can improve the stabilization of emulsions. Recently, it was discovered that by fusing these particles together, structurally rigid encapsulation devices, or colloidosomes can be created, of particular use in the precise control of drug delivery or encapsulation of biological material. Our research focuses on trying to understand how structurally rigid encapsulation devices and other micro structures can be self assembled using colloids with novel morphology and surface chemistry. The comparable size of these particles to the wavelength of visible light also suggests that these micro structures may be used to create materials with interesting optical properties.
Academic Appointments
2013-present: Assistant Professor- Bioengineering, ßÙßÇÂþ», ßÙßÇÂþ», NY
Industrial Positions
2003-2006: Senior Engineering Consultant (Computational Fluid Dynamics), I.D.E.A.S. Ltd., Glasgow, Scotland, U.K.
2000-2002: Aerodynamacist, Airbus U.K., Bristol, U.K.
Relevant Publications
G. K. German, E. Pashkovski, Y.Xu, A.F. Mertz, C. Hyland, W. C. Engl and E. R. Dufresne, 'Heterogeneous drying stresses in stratum corneum', Biophysical Journal, 102(11), pp 2424-2432 (2012).
A. F. Mertz, S. Banerjee, Y. Che, G. K. German, Y. Xu, C. Hyland, M. C. Marchetti, V. Horsley and E. R. Dufresne,' Scaling of Traction Forces with Size of Cohesive Cell Colonies,' Physical Review Letters, 108, 198101 (2012).
G. German and V. Bertola, 'The spreading behavior of viscoplastic drops,' Colloids and Surfaces A: Physiochemical and Engineering Aspects, 366, pp. 18-26 (2010).
G. German and V. Bertola, The free fall of viscoplastic drops, Journal of Non-Newtonian Fluid Mechanics, 165, pp. 825-828 (2010).
G. German and V. Bertola, 'Formation of viscoplastic drops by capillary breakup,' Physics of Fluids, 22, 033101 (2010).
G. German and V. Bertola, 'Review of drop impact models and validation with high viscosity Newtonian fluids,' Atomization and Sprays ,19, pp. 787-807 (2009).
G. German and V. Bertola, 'Impact of shear-thinning and yield- stress drops on solid substrates,' Journal of Physics : Condensed Matter, 21, 375111 (2009).
Education
- MPhys, The University of Edinburgh
- MS, Cranfield University
- PhD, University of Edinburgh
Research Interests
- Complex fluids
- Soft matter
- Cellular and Tissue mechanics
- Traction force Microscopy
- Cosmetic Physics
Awards
- 2009 Best presentation award – V. Bertola
- G.German
- Viscoplastic Fluids : From Theory to Application
- Limas sol
- Cyprus
- 2009.2006-2008 C. N. Davies Scholarship
- Aerosol Society 2006 J. M. Lessells Postgraduate scholarship award
- The Royal Society of Edinburgh