Science Café 2014-15
Wednesday, September 10, 2014
The origin of the elements
Malcolm Butler | Dean, Faculty of Science
We are stardust. Often a lyric or line in a poem, it is in fact true. Chemical elements have been formed since the early minutes of our observable universe’s existence, but the heavier elements so important to life and society today are a result of stellar explosions billions of years ago. We’ll survey the origin of elements, and efforts to understand the processes behind the synthesis of the heaviest chemical elements found in nature.
Wednesday, September 24, 2014
Multiple impacts of environmental change on lake and river ecosystems
Jesse Vermaire | Institute of Environmental Science
Humans are changing the structure and function of many ecosystems, including lakes and rivers. In fact, the extent of human impact on the environment has led many scientists to refer to the recent period of the Earth’s history as the “Anthropocene”, a new geological epoch marked by human domination of the Earth’s environment. Lake sediment records and long-term monitoring data provide a valuable tool for understanding the long-term impacts of environmental change on our freshwater ecosystems. This talk will focus on some of the impacts that land-use change, climate change, and invasive species are having on our lakes and rivers and discuss the complex, and sometimes surprising, interactions that multiple ecological stressors can have on ecosystems.
Wednesday, October 8, 2014
The mysterious world of fungi
Myron Smith | Department of Biology
The Fungi comprise an enigmatic group of organisms that is most closely related to the animal kingdom. Fungi are familiar to most of us as moulds and mushrooms, but we tend to overlook their profound impacts on human affairs as plant and animal pathogens and symbionts, in industrial fermentation processes, as decomposers and as research subjects. In this talk, I will provide a brief overview of the functional and structural diversity of fungi, and highlight some surprising aspects of their biology, genetics and behaviour.
Wednesday, October 22, 2014
Regulators of the Immune System: The Role of the Microbiome
Edana Cassol | Department of Health Science
The immune system is a complex network of cells and inflammatory mediators that protect the body from invading pathogens. In most healthy individuals, this system is tightly regulated to prevent the development of chronic inflammation and autoimmune disease. Recent studies have shown that human nutrition and the microbiome (millions of microbial cells composed of bacteria, fungi, and viruses found on or inside the body) play an important role in the development and regulation of these processes. During her presentation, Professor Cassol will explore how these millions of microbes regulate host immune responses and discuss how changes in these microbial populations contribute to malnutrition and the development of diseases such as diabetes, inflammatory bowel disease and Alzheimer’s disease.
Wednesday, November 12, 2014
Using PET to take better aim at cancer
Emily Heath | Department of Physics
Positron emission tomography (PET) images provide us with three dimensional maps of tumour cell properties. While traditionally x-ray images are used to guide radiation therapy treatments for cancer, there is now much interest in using PET images to identify and target radiation to the more aggressive parts of tumours. This talk will review how PET imaging works and its current and future applications in improving cancer treatment using radiation.
Wednesday, November 26, 2014
Flaxseed dietary fibre in yogurt and kefir can enhance the bioactivity and nutritional value
Farrah Hosseinian | Department of Chemistry
We don’t think of the gut when we think of cardio vascular diseases (CVD); however these two areas of the body are indeed linked. Lipid oxidation can cause chronic inflammations that could be a major risk factor for oxidative stress (e.g. heart disease). Because inflammation can be painless and frequently goes undetected, its relationship to disease has been poorly understood. Thus reduction of oxidation/inflammation will lead to improved levels of oxidative stress and lowered incidence of related diseases. Dietary fibers (DF) are nondigestible oligosaccharides and have been shown to enhance mineral (e.g. Ca, P, Mg) absorption and bone mineral accumulation when combined with probiotic bacteria. In plants, DF are mainly in conjugations with phenolics. DF can pass through the small intestine to the lower gut where they become available for some colonic bacteria. Flaxseed (usitatissimum L) is one of the richest sources of bioactives including omega-3 fatty acid, mucilage (soluble fibre) and lignans (diphenolics). Flaxseed mucilage is a by-product/leftover that is obtained after extraction of the flaxseed oil. Flaxseed contains approximately 28% dietary fibre in a ratio% of soluble to insoluble fibre of 20:80. Yogurt and kefir (fermented dairy products) are an important part of a healthy diet with demonstrated benefits to bone and dental health and overall body functioning properly. In Canada, production of yogurt sold increased by 45% between 2000 and 2013. The kefir market is growing rapidly and gaining popularity around the world, especially in Canada and the United States. Fermentation can be used as a novel tool to incorporate flaxseed DF into yogurt and kefir to enhance the bioactivity and nutritional value of the food product.
Wednesday, December 10, 2014
The theory of optimal mass transportation and its applications
Abbas Momeni | School of Mathematics and Statistics
Optimal mass transportation can be traced back to Gaspard Monge’s famous paper of 1781: "Mémoire sur la théorie des déblais et de remblais". The problem is to minimize the cost of transporting a given distribution of mass from one location to another. Since then, it has become a classical subject in probability theory, economics and optimization. This introductory presentation aims to familiarize the audience with this topic and some of its applications.
Wednesday, January 14, 2015
The 100th Anniversary of World War I: How Chemical Weapons Led to Cancer Chemotherapy
Jeffrey Manthorpe | Department of Chemistry
One of the most lasting impacts of World War I was the advent of modern chemical weapons and January 2015 is the 100th anniversary of their introduction. While the use of weapons such as chlorine and mustard gas in WWI are well known, this presentation will show the surprising scientific connections and history of how chemicals designed to kill enemy soldiers have led to medicines that now allow us to fight cancer, infections, mental illness, and cystic fibrosis.
Wednesday, January 28, 2015
Managing Mine Waste in Canada’s North
Richard Amos | Insitute of Environmental Science and Department of Earth Science
The recovery of resources such as gold and diamonds requires excavation of substantial amounts of rock that are permanently stored on the mine site in large piles. These waste-rock piles, when exposed to air and water, can leach acidic water with high concentrations of metals and other contaminants. Managing this waste in an environmentally responsible and socially acceptable manner is a major challenge for the mining industry and represents a significant financial liability. This talk will introduce you to research at the Diavik Diamond Mine in the Northwest Territories and the Detour Gold Mine in Northern Ontario that aims to better predict leach water quality and manage mine waste.
Wednesday, February 11, 2015
How Did They Know I Wanted That? Recommendation Systems and Social Influence
Anthony Whitehead | School of Computer Science
When visiting web sites, suggestions are often given regarding a choice to be made, an item to be bought or a web search that we might want to perform. These suggestions arise from the processing of large quantities of data collected through the tracking of user activity while individuals are visiting and interacting with certain sites. Processing this data leads to the creation of profiles; these profiles are then used to generate recommendations. Organizations use profiles and the social network of interactions between users to promote ideas and to influence the opinions of others. This talk will introduce the principles and practice of Recommender Systems, ideas of social influence and their use in today's online systems.
Wednesday, February 25, 2015
The Neurobiological Consequences of Being Born Very Premature
Natalina Salmaso | Department of Neuroscience
Babies born prematurely at a very low birth weight (<1kg) are at a major risk for brain injury with grave consequences such as high risk for neuro-psychiatric illnesses and developmental delays. The brain injury observed is largely due to oxygen deficits as a consequence of immature lung development. In our research, we study both the injury and the recovery process in order to design earlier and more efficient interventions.
Wednesday, March 11, 2015
Game Theory - What it is, and Why it Matters?
Tom Sherrat | Department of Biology
You don’t need to be an athlete to play games, you don’t need a beautiful mind and you don’t need to be a battlefield general. Whether we realize it or not, we all play games when we choose what line-up to join at a supermarket, when we decide whether or not to vaccinate our children, when we invest in the stock market and when we help our neighbour shovel their driveway. Even animals and plants engage in games when they allocate the sex of their offspring, and control how tall they should grow. Just like chess, games arise when the payoff from adopting a given strategy depends on the strategies adopted by others. So, if everyone around you is looking out for predators then it will pay to let others do the work; but if nobody is looking then it would pay to be vigilant. In this Science Café, I will explain how and why game theory has transformed modern economics and evolutionary biology. I will describe how solutions to games are identified, I will present you with some social dilemmas, and I will argue that this way of looking at the world can help explain everything from human cooperation to territorial coalitions in fiddler crabs.
Wednesday, March 25, 2015
Why Can't Computers Keep Secrets?
Anil Somayaji | School of Computer Science
Nobody seems to be able to keep secrets anymore. From Sony Entertainment to the NSA to the personal photos of celebrities, "data leaks" seem to have become a way of life. In this talk we will discuss how a convergence of technical and social factors has made it extremely difficult for anyone to prevent their private information from being exposed to the world. While there are some potential ways to prevent these disclosures, there is no "silver bullet" that will fix the problem - and this may actually be a good thing.
Wednesday, April 8, 2015
Environmental Factors and Disorders of the Immune System: Allergies and Beyond
Shawn Hayley | Department of Neuroscience
The immune system is highly dynamic and complex, having the ability to both respond to and neutralize potentially harmful pathogens while simultaneously leaving host tissues intact. Moreover, selective pressures present over the course of evolutionary history have favoured the development of a human immune system capable of living symbiotically with thousands of microorganisms. This collection of predominantly resident microbes is collectively referred to as the ‘microflora’ and becomes established within the first few years of life. The infant immune system depends on early activation from colonizing microbes to become functionally mature. Importantly, this early colonization process can be influenced by numerous environmental factors including exposure to antibiotics, toxicants and changes diet. Increasing exposure to such environmental factors, along with reductions in microbe exposure stemming from increased hygienic measures, might help explain the rise in allergies and immune disorders. Indeed, the microflora is known to have a profound effect on immune processes. As well, multi-directional communication between the immune system, hormonal, and brain systems is believed to influence the progression or onset of a host of human disorders. We currently posit that early life disturbances of the microflora will sensitize immune-hormonal processes leading to altered behavioural and biological responses relevant to clinical conditions involving immune hypersensitivity.