(Lawrence Szewciw completed his M.Sc. in 2009, and has been accepted to the Ph.D. program in Mechanical Engineering at McGill University starting Jan 2011)

Contact info: lawrence.szewciw@mail.mcgill.ca; http://barthelat-lab.mcgill.ca/people.html

Lawrence Szewciw with a section of the left baleen series from a 12 m-long female humpback whale (10/26/06)

                                                                                            L.J. Szewciw CV at bottom of page

Education:

B.Sc. Hons. Zoology, University of Guelph, 2006

M.Sc. Zoology, University of Guelph, 2009

Teaching assistantships:

ZOO*3200, Comparative Animal Physiology I, University of Guelph, Fall 2006 - 2007

Presentations:

The 46th, 47th and 48th Annual Meetings of the Canadian Society of Zoologists (2007 - 2009), Title of presentation: The structure and biomechanics of whale baleen alpha-keratin

The Gordon Research Conference on Intermediate Filaments (2008), Magdalen College, Oxford, England, Title of poster presentation: The structure and biomechanics of whale baleen alpha-keratin

Memberships:

Canadian Society of Zoologists, 2007 - 2012

Publications:  

Zhu, D., Fuentes-Ortega, C., Motamedi, R., Szewciw, L., Vernerey, F., and F. Barthelat. 2011. Structure and mechanical performance of a "modern" fish scale. Advanced Biomaterials (In press). *Won best paper at SEM (Society for Experimental Mechanics) 2011, Biological Systems & Materials Division. (click here to access the article)

Szewciw, L.J., De Kerckhove, D.G., Grime, G.W., and D.S. Fudge. 2010. Calcification provides mechanical reinforcement to whale baleen alpha-keratin. Proceedings of the Royal Society B 277(1694):2597-2605. (click here to access the article)

Fudge, D.S., Szewciw, L.J., and A.N. Schwalb. 2009. Morphology and development of blue whale baleen: An annotated translation of Tycho Tullberg's classic 1883 paper. Aquatic Mammals 35(2):226-252. (click here to access the article)

Fudge, D.S., Winegard, T., Ewoldt, R.H., Beriault, D., Szewciw, L., and G.H. McKinley. 2009. From ultra-soft slime to hard alpha-keratins: The many lives of intermediate filaments. Integrative and Comparative Biology 49(1):32-39.

Links:

(1) Article in At Guelph (April 23, 2010) - "Take a big gulp: U of G biologists study the way whales strain fish from seawater" (click here to access the article) - story picked up by:

Reef Conservation International (May 26, 2010),

Seaborn: Ocean Sciences Blogzine (May 26, 2010),

UnderwaterTimes (May 28, 2010),

Scuba Diving (May 28, 2010),

Hyannis Whale Watcher Cruises (May 30, 2010),

Wild About Whales - rewritten and retitled "Calcium the secret ingredient to Baleen" (June 22, 2010)

(2) Article in The Portico (Fall 2010) - "Guelph lab discovers the recipe for slime" (click here to access the article) - includes a paragraph about our baleen research

(3) Article on InnovationCanada.ca (October 6, 2010) - "A whale of a mystery: Unlocking the secret behind the formation of baleen" (click here to access the article)

(4) 3-min news segment describing our baleen research on the science TV show Découverte - aired April 3, 2011 on CBC Montreal. Also, the April 12, 2011 U of Guelph campus News included our Découverte/CBC media coverage (click here to read the U of G News story)

(5) Article on MaterialsViews.com (October 20, 2011) - "To protect and be served: The structural strength of fish scales" (click here to access the article)

Recently completed studies:

M.Sc. Zoology, University of Guelph, Project title: The structure and biomechanics of whale baleen alpha-keratin (click here to access an online preview of the thesis)

My research:

Recent work by my advisor, Dr. D.S. Fudge, suggests that intermediate filaments (IFs) in hard alpha-keratins are far stiffer than their IF counterparts in living cells. Possible mechanisms by which IFs in hard alpha-keratins are stiffened include: air drying, drying via syneresis (protein matrix squeeze), and covalent cross-linking. While it should be possible to increase the stiffness of IFs by introducing cross-links, this approach should not increase the yield stress as much as air drying or syneresis. To test this hypothesis, we are examining the material properties of whale baleen, a hard alpha-keratin that never has the opportunity for air drying. In addition, it is known that baleen contains high levels of calcium salts. We are therefore examining the mechanical roles of such calcium salts in baleen by conductng tensile and flexural tests on calcified and decalcified baleen specimens. As well, we have produced maps showing the distribution of Ca phosphate in baleen using proton-induced x-ray emission (PIXE). The analysis of the distribution and mechanical effects of calcium salt deposits in baleen is a collaborative effort with Dr. D.N. de Kerckhove of the University of Guelph Physics Department.

Dr. Fudge and I have initiated a few additional projects on the structure and mechanics of whale baleen:

Functional morphology of whale baleen:

Throughout the course of our research we have focused not only on the mechanics of baleen, but also on its functional morphology. We have several ideas about how the structure of baleen relates to its function in life, for example the link between calcium salt deposition and baleen abrasion resistance, which is important in the formation of a fringe of bristles, used in filter-feeding, at the inner (lingual) edge of the baleen plate.

Cell mechanics and the development of papillary horn:

We have initiated a collaboration with researchers at the University of Waterloo (the Brodland lab) to study the cell mechanics behind the development of cornified papillary epidermis, whale baleen being one example of papillary horn. The results of this collaboration will be relevant to the structure and development of all papillary horn, ranging from horse hooves to bird beaks.

Special thanks to Tonya Wimmer and D.F. McAlpine for provision of baleen samples

Lawrence Szewciw on top of Blue Mountain (06/15/10) overlooking Collingwood ON including the Collingwood Shipyards and Terminals (upper right corner of photo)