Science Café 2009-10
Wednesday, September 30, 2009
Fall 101: Why do leaves turn different colors?
Root Gorelick | Department of Biology
Wednesday, October 14, 2009
Fire and Ice: Geological field course to Iceland
Brian Cousens | Department of Earth Sciences
Iceland is truly a volcanologists paradise! Located in the north Atlantic Ocean, the island is a unique geological phenomenon: it sits over a large thermal anomaly in the Earth’s mantle, like Hawaii, but also lies on the mid-Atlantic Ridge where the seafloor is split apart and new crust is being produced. Thus, Iceland is divided onto two tectonic plates, the European and North American, and the island is the only place in the world where you can walk on a mid-ocean ridge since in all other places the ridge is below sea level. Due to the recent economic collapse in Iceland, a student field trip has become affordable. Along with a colleague from the University of Ottawa, Tony Fowler, we led a group of 19 undergraduate and graduate students on a two-week geological field course in August. The highlights included the Golden Circle tour to the fabulous Gullfoss waterfalls, the Geysir, and the original Icelandic parliament located in the mid-Atlantic ridge at Thingvellir; a full-day hike across the Hellisheidi and Nesjavellir geothermal area; a day-long trip to Hekla, Iceland’s most notorious volcano; a visit to the Westman Islands to see the town that was nearly destroyed by an eruption in 1973 and to catch a glimpse of Surtsey; studies of subglacial eruptions and lava-water interaction in south Iceland; the Vatnajokull glacier field; Krafla volcano and natural hot springs; and Snaefellsjokull volcano, made famous by Jules Verne in his “Journey to the Center of the Earth”. The geology of Iceland was even more spectacular than we expected, even on days with +4oC temperatures and horizontal rain. Fortunately, as the Icelanders say, “if you don’t like the weather just wait five minutes”, and we were blessed with breaks in the weather at times where we needed them.
Wednesday, October 28, 2009
Nanotechnology and health: Is nano safe?
Sean Barry | Department of Chemistry
Nanoscience and nanotechnology have become established fields in fundamental research as well as development for new materials and products. Due to the size of many nanomaterials (approximately 10 times the size of an atom), there is an acute concern about these materials and their interaction with biological systems. This talk will highlight the nature of nanomaterials, what work is being done to uncover their toxicology, and what role governments and other agencies are adopting to ensure the safe production and use of nanomaterials.
Wednesday, November 11, 2009
Why does my computer get sick?
Anil Somayaji | School of Computer Science
Computers get sick, and sometimes they even die. Such sickness comes in many forms, ranging from crashing systems to lost files to erratic, even dangerous program behavior. Even worse, our computers can be taken over by parasites---viruses, worms, rootkits---that turn computers against their owners. While some of these problems can arise from hardware problems, most come from issues with software. In this talk I will explain how software design and implementation errors, large and small, lead to the reliability and security problems of modern computer systems. I'll then sketch how ideas from biology can help us build healthier computer systems.Note that this talk only requires a background in using computers, not programming them.
Wednesday, November 25, 2009
Bahamian Bonefish: A PhD in paradise
Karen Murchie | PhD candidate, Department of Biology
Karen Murchie is a PhD student at Carleton University who is using bonefish as a model to understand how fish make a living in tropical tidal flats environments. Bonefish are a popular sport fish throughout their circumtropical distribution and thus can be economically important in small island nations such as The Bahamas. It is also believed that bonefish are ecologically important, moving nutrients from nearshore coastal areas, to offshore reefs. Come learn about bonefish, the environments they live in, why anglers love to catch them, and what it is like to do research in paradise.
Wednesday, December 9, 2009
The Evolution of Aging
Tom Sherratt | Department of Biology
As we get older our bodies tend to fall apart. Indeed, ageing is such a universal phenomenon that we tend to accept it without much further thought. However, from an evolutionary perspective, one might wonder why organisms are not selected to avoid ageing altogether. Indeed on the face of it, it is rather strange that we can produce healthy offspring from scratch, yet somehow seem unable to perform the much simpler task of indefinitely maintaining what has already been produced. One evolutionary theory is that ageing is actively programmed into individuals, so that older individuals that have accumulated injuries can avoid being a burden to the species, or the group to which they belong. More recent explanations suggest that it has arisen as a consequence of genetic “time bombs” that have not been purged by natural selection because so few individuals would normally live long enough to experience their effects. In this presentation, I describe these evolutionary theories and others. I then give my own opinions and discuss the prospects of humans living longer in the future.
Wednesday, January 13, 2010
Endophytes in conifer: Protecting forests again spruce budworm
J. David Miller | Department of Chemistry
Since first being made in 1876, Methylene Blue has gone from being used to stain cells in medicine to being a medicine itself - it's been explored in treatments for cancer, cyanide and carbon monoxide poisoning, malaria and several other areas. Perhaps most fascinating of all is that it is used to treat methemoglobinemia, a rare condition that causes the skin to appear blue.
Wednesday, February 10, 2010
Lovers and a dangerous time: The remarkable sex life of moose
Mike Runtz | Department of Biology
Moose appear to be quiet, innocuous animals for most of the year but during their breeding season, the Rut, they become highly animated and vocal creatures. This highly visual presentation will explore their ageless rituals of love, including the roles played by the bulls’ antlers.
Wednesday, February 24, 2010
Enzymes: Nature's molecular machines
Susan Aitken | Department of Biology
From the "butterfly effect" of weather prediction, to the vagaries of the stock market and the intricate beauty of snowflakes, examples of chaotic behaviour surround us. But what is chaos? Is it a manifestation some underlying random process? Is it a "catch all" for effects which we do not know or cannot resolve? In this presentation, Dr. Amundsen will talk about the mathematical theory of chaos, and how it applies to a wide range of every-day phenomena. You will learn that behind the mysterious, seemingly random nature of chaos lies a rich, intricately-woven structure. With this comes deeper understanding but such complexity also brings limitations. Through various examples we will explore how order emerges from disorder!
Wednesday, March 10, 2010
The Oxygen paradox: A tale of two extremes
Bill Willmore | Institute of Biochemistry
Oxygen is an essential element for aerobic life. We cannot live without it as our daily metabolism requires it. When oxygen "goes wrong", however, this can lead to disease states and general aging in all organisms. This talk will outline the process of how oxygen can become dangerous pro-oxidant "free radicals" and the types of damage to tissues and cells of the body when they do. The sources of such free radicals, derived from oxygen as well as environmental contaminants, will be reviewed. The talk will also discuss the general antioxidant defences that we have to protect ourselves from such damage and how these defences go down due to oxidative damage as we age. Finally, the clinical conditions that arise due to oxygen-derived free radicals (cancer, neurodegeneration, inflammation, cardiovascular diseases) will be presented as well as a (brief) overview of the mechanisms by which they occur.
Wednesday, March 24, 2010
Finding mates amongst the noise
Glenn Cunnington |
In July 4, 2012, the European Organization for Nuclear Research, known as CERN, announced the discovery of the Higgs Boson. The Higgs Boson describes the missing piece of the puzzle that would give mass to the objects in our Universe. Learn about this elusive particle and the Large Hadron Collider (LHC) experiments that lead to its discovery. Join Dr. Koffas as he explains why the Higgs boson is described by Maclean’s Magazine as “the biggest scientific achievement of a generation.”
Wednesday, April 7, 2010
What have we learned from the Sudbury Neutrino Observatory?
Alain Bellerive | Department of Physics
The Sudbury Neutrino Observatory (SNO) was a water Cherenkov detector dedicated to investigate elementary particles called neutrinos. It successfully took data between 1999 and 2006. The detector was unique in its use of heavy water as a detection medium, permitting it to make a solar model-independent test of solar neutrino mixing. In fact, SNO conclusively showed that solar neutrinos oscillate on their way from the core of the Sun to the Earth. This groundbreaking observation was made during three independent phases of the experiment. Even if data taking ended, SNO is still in a mode of precise determination of the solar neutrino oscillation parameters because all along SNO had developed several methods to tell signal and background events apart. This ability is crucial for the final and ultimate data analysis of all the phases. The physics reach of a combined three-phase solar analysis will be reviewed for a general public together with results and subtleties about solar neutrino physics.
Wednesday, April 21, 2010
Applied physics drives medical innovations
Paul Johns | Department of Physics
It's hard to imagine a hospital without an x-ray department or an mri scanner, or radiotherapy not being a treatment option for cancer patients.
Yet most of these technologies were rudimentary or did not even exist one or two generations ago, and even x rays were only discovered somewhat over a century ago. Applied physicists working on medical imaging and radiotherapy allowed these medical technologies to blossom during the 20th century. The pace continues and is increasing. This talk will look at how some of the technologies grew, where they are likely to go, and the people behind them.
Wednesday, May 5, 2010
Towards the accurate treatment of tumour
Tong Xu | Department of Physics
The talk will provide an over view of radiation therapy treatment of cancer and the current advances of the techniques. The focus will be on: why we need accurate delivery of radiation therapy, what is the current limitation, and how can we improve it.
Wednesday, May 19, 2010
New trends in drugs: Licit and illicit
Gerald Buchanan | Department of Chemistry
A short survey of some new approaches to pharmaceutical drug design will be described. These include isotope substitution of deuterium for hydrogen to produce “hydrogen heavy” medicines, new approaches to the synthesis of specifically handed versions of drugs and the development of Locked Nucleic Acid (LNA) based RNA inhibitors for cancer treatment.
Some licit drugs (including the potent painkiller Oxycontin) are being widely abused. Current trends in these and some other street drugs will be documented.