W. SCOTT DUNBAR
Associate Professor
Room 517F Frank Forward Tel.: 604 822 4725 Fax: 604 822 5599 [email protected]
o Biography o Research Interests o Selected Publications BiographyEducation
BSc Geophysics (Honours), University of British Columbia, 1972 MSc Geophysics, University of Toronto, 1973 PhD Civil Engineering/Geophysics, Stanford University, 1977 The first twenty years of my career were spent in civil and geotechnical engineering consulting. Over that period I was involved in projects such as tailings dam and waste dump design, open pit and underground mine design, and water resources projects including hydroelectric dams. In addition to North America, these projects took me to Africa, South and Central America, and Europe. (Guatemala was a favorite.) In 1997 Dr Rick Lawrence, Department Head at the time, invited me to join the Department. Since I had always enjoyed teaching and research, it was not a difficult decision to apply for the position. I was at a point in my career when I was ready for the change. Although my background is civil/geotechnical, I am interested in what a mine is going to look like in the year 2050 or even 2100. Can we go on extracting minerals the way we have been or should we be looking at alternatives? What alternatives? Some ideas are discussed in my Research Interests but I believe we should look way “outside the box” since otherwise mining engineering will not advance. I teach Mine Design to undergraduate students and Mine Economics to both undergraduate and graduate students. I also teach a graduate course in the use of decision analysis and simulation in engineering. In addition to my responsibilities with Mining Engineering I was the founding director of Integrated Engineering, a new inter‐disciplinary engineering degree with heavy emphasis on
design (see www.igen.ubc.ca). The program has been quite successful and has graduated about 120 students all of whom are employed in different industries. The counter‐balance for a busy work schedule is sports (cycling, cross‐country and downhill skiing), re‐modeling and re‐landscaping an old house with the help of my wife, Petra, and spending time with two sons, one young daughter, and two grown daughters. I also like to read and travel. Music? I am an unabashed blues aficionado. There was a blues singer named Scott Dunbar from Lake Mary in Mississippi who played a raw and basic style. Looked nothing like me. I wish I could have met him before he died in 1994 (See http://sundayblues.org/archives/215)
ResearchInterestsNature likes to keep numbers in control. So what keeps bacteria from replicating to produce excessive numbers? The answer: bacteriophage (or simply phage). The sole purpose of phage is to replicate by infecting bacteria; they are harmless to humans, animals, and plants. There are several species of phage and each infects a limited range of species of bacteria. Phage are the most numerous biological entity in the biosphere. They are widely distributed and exist wherever there are bacterial hosts. It is estimated that phage infect half the world’s bacteria every ten days. What has this got to do with mining? Read on. The common feature of phage is a protein coating (a capsid) which surrounds genetic material such as DNA or RNA. There are enough genes in the genetic material to encode the information to make the phage capsid, but the phage does not have a metabolic system to generate energy or the genetic precursors required for reproduction. (For this reason phage are not considered to be alive.) The purpose of infection is to insert the genetic material and use the machinery of the host cell to synthesize proteins and reproduce. Shown below is a cartoon of the M13 phage particle which infects the E coli bacterium. The particle consists of DNA surrounded by different protein coatings, labelled Px. M13 is very small. By way of comparison, the diameter of a human hair is about 20‐180 microns, at least four orders of magnitude larger than the diameter of M13.
Without compromising the ability of the particle to infect E coli, short peptide sequences (foreign sequences) can be fused to some of the protein coatings of the particle. Libraries of phage with about one billion different foreign sequences can be constructed. In collaboration with the Centre for Blood Research at UBC, such libraries have been used to identify foreign protein sequences on M13 that bind to minerals of economic interest such as chalcopyrite and sphalerite. We tagged the binding phage particles with a fluorescent antibody and then introduced the tagged phage (millions of them) to a mixture of silica and sphalerite particles 45‐75 microns in size. The fluorescence image at about 200× magnification is shown below. The
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SelectedPublicationsCurtis SB, Hewitt J, MacGillivray RTA, Dunbar WS, 2009. Biomining with bacteriophage:
Selectivity of displayed peptides for naturally occurring sphalerite and chalcopyrite. Biotechnology and Bioengineering 102:644–650.
Curtis SB, MacGillivray RTA, Dunbar WS, 2011. Effects of bacteriophage on the surface
properties of chalcopyrite (CuFeS2), and phage‐induced flocculation of chalcopyrite, glacial till, and oil sands tailings. Biotechnology and Bioengineering, 108(7):1579‐1590
Curtis SB, Dunbar WS, MacGillivray RTA, 2012. Bacteriophage‐induced aggregation of oil sands
tailings. To be submitted to Biotechnology and Bioengineering Dunbar, WS, 2012. Applications of synthetic biology to mineral processing. In preparation Dunbar, WS and Russell AD, 2012. Continuous cash flow models of non‐market risks. To be
submitted to Resources Policy Grieco S‐HH, Seungil L, Dunbar, WS, MacGillivray, RTA, and Curtis, SB, 2009. Maximizing
filamentous phage yield during computer‐controlled fermentation. Bioprocess and Biosystems Engineering, 32:773‐779
Gunson, AJ, Klein, B, Veiga, M, Dunbar, S, 2010. Reducing mine water network energy
requirements. Journal of Cleaner Production, 18:1328:1338