* Getting a Toe-hold on Early Prosthetics * Artificial Intelligence wins Gold * Leaf-cutters, When they Can't Cut It * Spit Out Your Genes *

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Getting a Toe-hold on Early Prosthetics

mummy_toe.jpgAn ancient Egyptian false toe. Courtesy, Jacky Finch, with permission from the Egyptian Museum, Cairo, Egypt
Two false toes, dating back to ancient Egypt, are believed to be the oldest known prosthetic devices.  Both are big toes from the right foot, and both were found near present-day Luxor.  One toe, found in the 19th century, is thought to have been made in about 600 BC. It is crafted from one piece of cartonnage - a linen and animal glue version of papier-mache.  The other toe dates back to between 950 and 710 BC.  It was found attached to the foot of a mummy in a tomb just over ten years ago.  This toe is comprised of three pieces, two are wood, the other possibly leather.  It had been suggested that because ancient Egyptians believed the body should be prepared for the afterlife in a complete state, the toes were purely decorative.  But new research by Dr. Jacky Finch at the KHN Centre for Biomedical Egyptology at the University of Manchester, England, proves otherwise.  The toes were recreated to fit amputee volunteers and tested for flex, pressure, gait and comfort.  Both performed remarkably well as functioning prosthetic toes.

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Artificial Intelligence wins Gold

Canada's highest prize for science and engineering, the Gerhard Herzberg Canada Gold Medal, was awarded this week to Professor Geoffrey Hinton for his pioneering work on Artificial Intelligence and Neural Networks.  Dr. Hinton, a professor at the University of Toronto and fellow of the Canadian Institute for Advanced Research, has worked to develop computers that can respond intelligently to the complexities of the real world, by developing techniques that help computers learn in ways similar to the human brain.  It's an interesting coincidence that Dr. Hinton was recognized for this work in the same week that IBM's Watson computer won on the game show, Jeopardy

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Leaf-cutters, When they Can't Cut It

Leaf-cutter ants use their razor-sharp mandibles for slicing leaves into small disc-like shapes, which are then carried back to underground nests and turned into food.  The ants doing the actual cutting are usually members of the generalized forager caste; one of four size-based behavioural castes of workers.  Such division of labour is well known in social insects like ants.  But new research by Dr. Robert Schofield, a Senior Research Scientist in the Department of Bio-Physics at the University of Oregon, has found that the mandibles of those ants doing the cutting become dull over time.  Even though the blades are made of a zinc-rich material that is wear-resistant, it is not wear-proof.  The study shows that when leaf cutting starts to take about three times longer than normal, those ants are re-assigned.  Similar to humans who experience declining skills due to age, the ants take on more age-appropriate tasks.  In this case, they stop cutting and become carriers. 

Related Links
  • Paper in Behavioral Ecology and Sociobiology
  • News from University of Oregon
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Spit Out Your Genes

DNA_kits.jpg DNA testing kits

This month marks the 10th anniversary of the sequencing of the Human Genome.  The project marked the beginning of a new age of genetic research - and promises of new remedies and cures for genetic diseases. One byproduct of the new world of genomics is already a reality: the direct-to-consumer, home genetic test.  You can now get your DNA analysed from the safety and comfort of your own home.  And while it may not be cheap, it is relatively quick, convenient, and easy.  But the tests come with a fair bit of controversy. So we asked Quirks contributor, and freelance science journalist Alison Motluk, to be our guinea pig, and submit her own DNA for home genetic testing. She sent her spit and cheek swab samples to 2 companies: 23andMe, and DeCode Genetics.

Chris Trevors is a genetic counselor at Sick Kids Hospital in Toronto and secretary of the Canadian Association of Genetic Counselors. He thinks people shouldn't do these tests without thinking very carefully about them. There are a lot of implications and they can go beyond just your own personal health, such as whether to share bad news with siblings who share your genes.

Dr. Joanna Mountain is a geneticist and Senior Director of Research at 23andMe. She says we may know a bit about our family's health history, but genetics can fill in the gaps and provide valuable information - especially for adopted persons. And she feels home testing kits can make it easy and accessible.

Dr. Timothy Caulfield is a lawyer and bioethicist at the University of Alberta in Edmonton. He says  the average person doesn't know how to interpret the test results, especially when they involve degrees of risk for developing a particular disease. Dr. Mountain disagrees. He also fears that people will over-react to an increased genetic risk, by either seeking unproven therapies or becoming fatalistic.

In Canada, Direct-to-Consumer genetic testing is unregulated, as it falls outside the scope of both the Food and Drug Act, as well as the Medical Devices Regulations from Health Canada. In the US, the FDA has recently warned companies that sell laboratory-to-consumer genetic testing that their products cannot be marketed without FDA approval.   

Related Links
  • 23andMe
  • deCODEme
  • Dr. Caulfield's paper in Science: Regulating Direct-to-Consumer Personal Genome Testing
  • CBC news story
  • TEDMED Talk by 23andMe founder Anne Wojcicki on benefits of genetic testing
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Theme music bed copyright Raphaël Gluckstein, Creative Commons License by-nc-nd-2.0