6 October 2003
Surviving Extreme Physiological Stress: Molecular Chaperone Function During Development of Artemia Embryos
Tom MacRae, Department of Biology, Dalhousie University
Encysted embryos of the brine shrimp, Artemia franciscana, exhibit remarkable ability to withstand stress, including reduced metabolic activity, desiccation and years of anoxia while fully hydrated and at physiological temperature. Stress resistance in Artemia seemingly depends on the developmentally regulated synthesis of a small heat shock/α-crystallin protein termed p26, shown to possess molecular chaperone characteristics in vitro and in vivo. Molecular chaperones are instrumental in the correct folding of proteins; they also direct proteins to intracellular compartments and prevent irreversible protein denaturation during stress. Purified p26 has been characterized and is cDNA sequenced. Modification of p26 cDNA by site-directed and deletion mutagenesis, followed by expression in bacteria, cultured mammalian cells and transgenic Drosophila, revealed mechanistic aspects of p26 function. Of particular interest are the relationships between protein structure, cell localization, chaperone activity and thermotolerance induction in transfected cells synthesizing p26. Cloning experiments elucidated p26 gene structure and may indicate how expression of the gene, which is greatly up-regulated as Artemiaembryos encyst and enter diapause, is regulated. The studies have revealed interesting aspects of Artemia development, an intriguing organism which plays an important role in aquaculture. p26 also serves as a model protein for analysis of other small heat shock/α-crystallin proteins, thought to have critical functions in cataract prevention and possibly in “conformational” diseases. Practical applications of the work include the generation of mammalian cells exhibiting p26-dependent dehydration tolerance.
3 November 2003
Cancer Care: The Model…The Program…The Outcome
Andrew Padmos, Commissioner, Cancer Care Nova Scotia
Cancer control is complex, multifaceted, multisectoral and multidisciplinary. Organizational models vary in Canada from province to province and some are in transition. The Nova Scotia model inaugurated in 1996 is unique as an integrating, facilitating coordinating program of the Provincial Department of Health. Cancer Care’s early development will be described with examples of success and sources of frustration. The cancer system offers many insights into health care in Canada, particularly in the areas of chronic disease management and technological change.
1 December 2003
“…the coolest place to play and learn…”
Discovery Centre’s Approach to Science Education
Dena Simon, Director of Operations, Discovery Centre
Terry Roberts, Program Coordinator, Discovery Centre
It seems that every year in recent memory, when the latest batch of Canada-wide standardized test scores is released, Nova Scotian students place near the bottom. Why is that happening? Are our students less scientifically inclined or are there other variables at work? By showing how science fits into our everyday lives, Discovery Centre aims to remove the barriers that stand between science and learners…and the public in general. The philosophy can be summed up in the tag line, the coolest place to play and learn. A fun, hands-on approach is used to spark interest in “all things science”.
Come and bring your family and friends for an evening at Discovery Centre. The visit will include a brief presentation on Discovery Centre’s history and its approach to science education, as well as science demonstrations, hands-on workshops and of course time to play with the exhibits.
5 January 2004
Sleep—What It Can Do For You?
Benjamin Rusak, Departments of Psychiatry and Psychology, Dalhousie University
A brief overview of what sleep is and what sleep is not, focusing on the stages of sleep and on some of the mechanisms involved in regulating it. The talk will include a discussion of the consequences of not sleeping adequately, and review some recent research that attempts to answer a very old, and very difficult question: Why do we sleep?
2 February 2004
Composting in Halifax Regional Municipality
Jeff Traver, Miller Waste Systems; Operations Manager, HRM Material Recovery Centre
A brief overview of HRM’s existing source-separated organics program, its history and how it came into being. The focus of the presentation will revolve around what happens once the organics are delivered to the facility, how they are processed, the technology employed, and what parameters are monitored to ensure the efficient decomposition of the organic waste. The presentation will conclude with a brief explanation of the benefits of finished compost and the end markets.
1 March 2004
Mussel Monitoring: The Good, the Bad and the Safe Supply
Shawna MacKinnon, Institute for Marine Biosciences, NRC
The presentation will describe research conducted at the Institute for Marine Biosciences which helps ensure that our mussels are safe for human consumption. The talk will outline how the National research Council’s marine toxin team develops monitoring systems and toxin standards used around the world, as well as how they identify and characterize the chemical structures of new marine toxins that could affect the mussel industry.
5 April 2004
Underwater Observations of Novel Behaviour in the Greenland Shark, Somniosus microcephalus
Chris Harvey-Clark, University Veterinarian, Dalhousie University
Predator or scavenger? Greenland sharks (Somniosus microcephalus) are huge, slow-moving deep-sea Arctic sharks—everything from whole seals to caribou has been found in their stomachs. Virtually nothing is known about the biology of these rare animals. Dr. Harvey-Clark and his colleague, Jeffrey Gallant, have searched Canadian waters for this shark with expeditions to the Arctic, Saguenay region and St. Lawrence River. In June 2003, they discovered and documented a transient concentration of these rare sharks in the Gulf of St. Lawrence. These first-ever natural encounters allowed remarkable observations of this strange and enigmatic animal. This will be the first public presentation of these observations.
3 May 2004 (Annual General Meeting)
The Evaluation of Electrotherapy and its Introduction into Nova Scotia in the Nineteenth Century
Allan Marble, Department of Electrical and Computer Engineering, Dalhousie University
Scientific medicine began to emerge in the early 1870s and gradually replaced heroic or depletive therapy which had been practised by “regular” or allopathic physicians for several centuries. The first half of the nineteenth century had witnessed a clash between these “regular” physicians and unorthodox or “irregular” physicians who practised alternative therapies. One of these alternative therapies was electrotherapy which had been practised since Greek and Roman times. My presentation will begin with a discussion of the rationale among the Greeks and Romans for the use of amber, magnetite, and the electric fish as therapeutic agents. I will then move to the post-medieval period and discuss the introduction, and the therapeutic use, of the von Guericke electric generator, the Leyden jar, and Galvanic electricity.
The focus of my presentation will then turn to Nova Scotia and I will discuss the reaction of physicians and other educated individuals in this province to the use of electricity and magnetism as therapeutic agents. It will be shown that developments in the understanding of electricity and magnetism which took place in Europe in the 1820s were closely monitored by Rev, Thomas McCulloch who began to offer courses on electricity and magnetism in the early 1830s. Mechanics Institutes soon began to appear all over the province and one of the main topics discussed at their meetings was electricity and electrotherapy. Although there was considerable excitement among physicians during this period about electrotherapy it will be shown that its credibility waned during the last half of the nineteenth-century partly because of the introduction of scientific medicine and partly due to the arrival of several charlatans who advertised that electric and magnetic devices would cure every illness and disease. Regular physicians distanced themselves from these “medical electricians” and, as a result, electrotherapy did not become a viable and accepted therapy until the twentieth century.