/oss/taxonomy/term/559/all en /oss/article/student-contributors-general-science/brightening-traffic <p>Red signifies danger in many cultures. From a distance, green is highly visible by day. At night, yellow is easier to see. That briefly explains the <i>choice</i> of colours on every traffic light. But what makes lights <i>emit</i> those colours in the first place?</p> Thu, 12 May 2022 15:41:45 +0000 Haleh Cohn 9110 at /oss /oss/article/videos/right-chemistry-bible-snails-and-colour-blue <p></p><div class="media-youtube-video media-element file-default media-youtube-1"> <iframe class="media-youtube-player" id="media-youtube-oxyvk52vkbc" width="640" height="390" title="Dr. Joe Schwarcz: The Bible, snails and the colour blue" src="https://www.youtube-nocookie.com/embed/OxYVk52vkbc?wmode=opaque&controls=&enablejsapi=1&modestbranding=1&playerapiid=media-youtube-oxyvk52vkbc&origin=https%3A//www.mcgill.ca&rel=0" name="Dr. Joe Schwarcz: The Bible, snails and the colour blue" frameborder="0" allowfullscreen="">Video of Dr. Joe Schwarcz: The Bible, snails and the colour blue</iframe></div> Fri, 14 Feb 2020 16:37:59 +0000 Joe Schwarcz PhD 8111 at /oss /oss/article/videos-history/right-chemistry-william-henry-perkins-discovery-mauveine <p></p><div class="media-youtube-video media-element file-default media-youtube-2"></div> Mon, 06 May 2019 19:24:09 +0000 Joe Schwarcz PhD 7748 at /oss /oss/article/did-you-know-nutrition/you-can-determine-colour-egg-looking-chickens-earlobe <p>Yes, that's right. Chickens do have ears although they are hidden by the feathers on the side of the head. But when the feathers are pushed aside, the openings that serve as ears appear. There is no outer ear, such as we humans have, but chickens do have earlobes which can be clearly seen. The colour of the lobe varies with the breed of the chicken, ranging from white to almost black. Chickens with white earlobes lay white eggs exclusively while birds with dark lobes lay brown eggs. The fascinating Araucana breed of chickens can even have earlobes that are a pale green or blue colour.</p> Thu, 18 Apr 2019 19:35:12 +0000 Joe Schwarcz PhD 7725 at /oss /oss/article/health/colour-meat <p>It’s a different world today, especially if you shop for your meat at a supermarket. You select your cut, pre-packaged meat from the refrigerated case, and the butcher who prepared it may not even be at that location. This is “centrally processed, case-ready meat” referred in the industry as CPRM. The central processing facility may be miles away from the supermarket. Of course, there is an economic consideration to central processing but it also helps deliver a safe, consistent, high-quality product with longer shelf life. And there is a lot of science involved here.</p> Thu, 03 Jan 2019 17:00:00 +0000 Joe Schwarcz PhD 7505 at /oss /oss/article/health-technology/can-these-glasses-put-end-colour-blindness <p>Serendipity plays a big role in science. Many discoveries begin with a puzzling observation followed by, “That’s weird”. Don McPherson developed special lenses for surgeons to use when employing lasers and he lent them to a colour blind friend on a Frisbee field. His friend reported he could now see the orange cones on the field. He’d never seen them before. That’s weird.</p> <p>But not every “that’s weird” moment results in game-changing technology.</p> Wed, 12 Dec 2018 19:13:47 +0000 Jonathan Jarry, MSc 7485 at /oss /oss/article/did-you-know/did-you-know-when-you-are-drinking-tea-you-are-also-drinking-some-ink <p>Like any plant, the tea plant is composed of hundreds of different compounds. Some of the most interesting ones fall into the category of polyphenols, so called because of their molecular structure. These compounds, specifically a sub-category called “tannins” are responsible for the dark colour you sometimes get in tea and they also account for the possible health benefits of tea.</p> Thu, 22 Nov 2018 17:00:00 +0000 Joe Schwarcz PhD 7460 at /oss /oss/article/did-you-know/can-you-change-your-eye-colour <p>Increased media attention on beauty and perfection has influenced many to turn to cosmetic surgery. A recent survey revealed that, if possible, many would consider altering their eye colour. Now, Dr. Gregg Homer, a U.S. Doctor, claims that this will be possible via a new laser procedure. The procedure starts with a computerised scan of the patients’ iris so a laser can hit one spot on the iris at a time, to heat up the pigment cells.</p> Tue, 25 Apr 2017 18:16:37 +0000 Joe Schwarcz PhD 2414 at /oss /oss/article/history-you-asked/who-invented-scotch-tape <p>The Scots did not invent Scotch tape. But their reputation for thriftiness did inspire the name of this amazing product. Two-tone cars were the in thing way back in the 1920s and car manufacturers were faced with the problem of how to cut clean, crisp lines between the colours. Before spraying on the paint, they would mask one side of the line with newspaper to create a sharp, straight edge.</p> Fri, 16 Mar 2012 16:08:32 +0000 Joe Schwarcz PhD 1685 at /oss /oss/article/general-science-you-asked/why-milk-white-and-not-green-grass <p>Questions about milk are always interesting because, after all, it is our first food. Milk is meant to be the only sustaining food during early life and therefore it must contain all the required nutrients: water, proteins, fats, milk sugar, vitamins and minerals. Chlorophyll, the green colouring agent in plants, is not a required human nutrient and therefore evolution has not resulted in it being incorporated by the mother's body into milk. This is not to say that milk has no coloured substances in it, it does.</p> Wed, 31 Oct 2012 21:58:13 +0000 Joe Schwarcz 1730 at /oss /oss/article/general-science-history/carmine-dye-and-cochineal-insect <p>At least in a manner of speaking. When Hernan Cortez came to America in 1518 he was intrigued by the beautifully coloured Aztec fabrics, particularly the stunning reds. He asked the natives about the source of the colorant and was shown some specks on a cactus plant. Closer scrutiny revealed that the little specks were actually little bugs. Today we know them as Dactylopius coccus, or simply as cochineal. The dye that can be extracted from these insects is called carmine. Montezuma was so fond of it that he imposed a tax upon his subjects that had to be paid in dried cochineal bugs.</p> Wed, 15 Feb 2017 21:55:27 +0000 Joe Schwarcz PhD 1462 at /oss