The Life and Work of Donald O. Hebb, Canada's Most Famous Psychologist

Donald O. Hebb is best known for his neurophysiological postulate on learning, which appeared in his book The Organization of Behavior (1949, reprinted 2002). Psychologists and neuroscientists associate Hebb with the Hebbian synapse and the Hebbian learning rule, and much of our current understanding of functional neural connections is based on Hebbian concepts. But Hebb's work has also influenced developmental psychology, neuropsychology, perception and the study of emotions. Hebb's work with Wilder Penfield set the stage for the development of neuropsychological testing. His rearing of rats in an enriched environment initiated the idea that environmental input could alter neural development and that sensory-neural connections were shaped by experience. This presentation reviews Hebb's life and work and its lasting influence in psychology and neuroscience in honour of the centenary of his birth in 2004.

The LIDAR in Laser Atmospheric Studies at Dalhousie University

A lidar (laser radar) system for atmospheric research was constructed in the Atmospheric- Optics Laboratory of Dalhousie University, and is used to measure clouds and airborne aerosol particulates. The overall design of the lidar will be described, and the background for our research will be explained. Lidar measurements were obtained this past summer during the international ICARTT campaign at Chebogue Point, Nova Scotia, using the new CABOT (Canadian Atmosphere-Biosphere Observations Trailer) Observatory. The measurements showed a variety of pollution events, including a plume of smoke originating from forest fires in Alaska and the Yukon. We are using the data to help improve our understanding of atmospheric pollution processes, an area of increasing interest worldwide due to the ongoing proliferation of megacities.

Fates of Polycyclic Aromatic Hydrocarbons in Marine Organisms

With population expansion and industrial developments, our society uses and produces more substances, includin g chemicals with potential associated toxicity. Polycyclic aromatic hydrocarbons (PAH) derive from combustion sources and fossil fuels, with aquatic environments representing a major sink for these compounds. There is a widespread interest in assessing the exposure of organisms to PAH and determine ecosystem health. Depending on the species studied, fate can be more or less complex and challenging to link with effects. Some of our resea rch "to ensure healthy, safe and prosperous oceans for the benefit of current and future generations of Canadi ans" will be discussed.

How to Protect Your Computer from Hackers

High speed internet connections, wireless networking, email and instant messaging are very convenient for comm unications across the internet. They also provide more opportunities for hackers to attack your home or office networks. Learn how hackers infiltrate home and small office networks and how to secure your PC from attacks. You will see actual examples of how a hacker gathers information about you over the internet and how to test your internet connection and home networks for security leaks. Also learn about SPAM filters and how to preven t spammers from obtaining your email address and many other aspects of computer security.

Antibiotic Use on the Farm: Implications for Human Health?

Many Canadians are concerned about the growing problem of antibiotic resistance. Older antibiotics are often n o longer effective. We now encounter patients infected with bacteria resistant to all of the commonly used ant ibiotics. Clearly, bacteria are evolving rapidly in the face of antibiotic pressure. Antibiotics are overused by physicians; however, more antibiotics are used on the farm. I will discuss the many factors that drive bact erial evolution from an antibiotic-resistance perspective. I'll also discuss the role that non-human use may p lay in promoting resistance in bacteria causing human infection.

Filling the Void—Discovering Life Beneath the Seas

Ninety-five percent of the volume of the world's biosphere is found in the oceans, yet scientists have sampled only a small fraction. In recent years discoveries of new species and even of new phyla have captured our ima gination, while in Nova Scotia, deepwater coral reefs have been photographed for the first time. DNA technolog ies have also uncovered a vast world of minute life and revealed cryptic variation even in large, well-studied organisms. Here in Atlantic Canada, marine scientists have formed a league, the Centre for Marine Biodiversit y, to focus attention on Discovery Science. This talk will highlight some of these biological discoveries and take you into the world of exploration!

Hurricanes and their Impact on the Forests of Nova Scotia

As a peninsula jutting into the Atlantic Ocean, the forests of Nova Scotia are especially vulnerable to storms and hurricanes tracking up the eastern seaboard of North America. Over the past couple of centuries, more tha n 20 major storms of hurricane intensity have affected Nova Scotia. As a natural disturbance these winds are a vital process in the ecology of the provincial forests either by creating a catastrophic destruction of fores t stands such as that which occurred at Point Pleasant Park, Halifax or as a gap-type single tree or small pat ch opening in hardwood forests. These wind storms are a natural mechanism for forest renewal and rejuvenation. Hurricane winds may be expected at almost any season of the year, and are a threat to all classes of forest. Shallow rooted softwood forests on soils saturated with the fall rains and still unfrozen are particularly vul nerable to extensive blowdown. This talk will highlight the ecological impacts of hurricanes on the forest of Nova Scotia and discuss the potential for increased wind storms for the future.

The Role of Materials Research in Your Daily Lives

Our lifestyles, and even our lives, depend on materials and the application of their properties, from plastics to medical implants. Materials research, formally defined, is the investigation of the relationships between and among the structure, properties, processing and performance of materials. In this presentation some fascinating examples of the development of materials and the links to consumer products, from ancient to futuristic, will be explored.

Special Lectures

5 October 2004

Sable Island: Uncertain Future?

Who's looking after Sable Island? Zoe Lucas, biologist and long time resident of the Island, will be giving a slide presentation on Sable Island and the important role that the Island's Station and staff play in the conservation of this utterly unique place. A panel discussion focusing on the uncertain future of the station will follow Zoe's presentation.

Vision and Brain: The Results of a Half Century of Research

The work he will describe began around 1955, in Washington, D.C. and Baltimore, and continued, in collaboration with Torsten Wiesel, in Boston, for the next 15 years. Dr. Hubel will outline their research on the role the cerebral cortex plays in interpreting the information it receives from the two eyes. He will then describe how the environment can influence the development of connections in the brain, early in life.