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Bernard Courtois and his beautiful violet vapor

It’s chemistry time again, folks… Today we celebrate the birthday of Bernard Courtois (8 Feb 1777 – 27 Sep 1838), the French chemist from Dijon who discovered iodine.

Iodine, courtesy of Bernard Courtois.(© All Rights Reserved)
Iodine, courtesy of Bernard Courtois.
(© All Rights Reserved)

Courtois’ father worked as a saltpeter manufacturer, and instilled in his son an interest in chemistry and pharmacy. He studied pharmacy and, while working with Armand Seguin at the Ecole Polytechnique, he investigated opium. During this period, Courtois and Seguin managed to isolate pure morphine, the first known alkaloid, from opium.

His greatest contribution, however, came after he returned to Dijon to assist in his father’s saltpeter business. Traditionally, wood ash was used as the source of potassium nitrate for the saltpeter, but due to a wood ash shortage they turned to using seaweed as an alternative source. In 1811, while extracting sodium and potassium extracts from seaweed ash, Courtois accidentally stumbled upon a new element – adding sulfuric acid to the ash resulted in the appearance of a beautiful violet vapor that condensed into deep violet crystals resembling graphite.

Iodine has since proved an important trace element in human and animal biology. It is a key constituent of the thyroid hormones thyroxine and triiodothyronine. The thyroid gland requires about 70 µg/day to synthesize these hormones, but additional iodine (RDA 150 µg/day for adults) is necessary to support the function of a range of biological systems in the body. Since iodine is scarce in nature (it is mainly available, as Courtois discovered 200 years ago, in ocean-based sources such as seaweed) it is often included as an additive in iodised salt, for example, to ensure that we get a sufficient daily dose.

Even though Courtois did not, at the time, realise that he had discovered a new element, he was subsequently acknowledged as the true discoverer of iodine. In 1831 he received the Montyon Prize from the L’Academie royale des sciences for his work. He never gained any financial benefit from his discovery, though, and his obituary in the Journal de chimie médicale strikes quite a sad note:

“Bernard Courtois, the discoverer of iodine, died at Paris the 27th of September, 1838, leaving his widow without fortune. If, on making this discovery, Courtois had taken out a certificate of invention, he would have realized a large estate.”

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Everything is coming up roses

Today, 7 February, is Rose Day, apparently conceived to mark the start of Valentine week*.

Valentine week!? As if Valentine’s Day isn’t already more than enough! It seems some clever marketer has decided there’s yet more money to be squeezed out of the poor consumer, who is scarcely back on his feet after the Christmas marketing onslaught.

'First Love' hybrid tea rose. (© All Rights Reserved)
The ‘First Love’ hybrid tea rose from New Zealand – a rose of classic beauty.
(© All Rights Reserved)

While Rose Day may have seen the light as part of an extended Valentine’s sales pitch, that does not mean we shouldn’t use the occasion to celebrate roses for what they are – really interesting, and rather lovely, flowers.

Roses are nothing if not diverse. In total there’s more than 100 species of roses, including bush roses, climbers, erect schrubs and miniature roses. While most are used as ornamental plants or as a favourite among cut flowers, roses are also used in the making of perfume, as well as in cooking and medicine. Rose hip (the berry-like ‘fruit’ at the base of the flowers of certain rose species), which is a rich source of Vitamin C, can be made into jams and jellies, while rose syrup can be made from an extract of rose flowers. Rose water (obtained as a by-product from distilling rose petals) is used in cooking and natural medicines. The Rosa chinensis species is used in traditional Chinese medicine for stomach problems and, linking back to World Cancer Day, this species is also being investigated as a substance for the control of cancer growth.

Not bad for a flower often taken for little more than a rather cheesy ‘symbol of love’.

The 'Chinensis Mutabilis' Chinese heirloom rose (© All Rights Reserved)
The ‘Chinensis Mutabilis’ Chinese heirloom rose – a picture of elegance and simplicity.
(© All Rights Reserved)

On a rather unrelated note, I’ve discovered that ROSE also happens to be an acronym for the Relevance of Science Education project. According to the site, “ROSE, The Relevance of Science Education, is an international comparative project meant to shed light on affective factors of importance to the learning of science and technology. Key international research institutions and individuals work jointly on the development of theoretical perspectives, research instruments, data collection and analysis.”

Now surely science education is something worthy of celebration, so there’s another angle to ROSE Day allowing you to celebrate the day while steering clear of the Valentine’s Day connection.

So, whether you’re a lover, a cook, a poet, an artist or a scientist, surely there’s more than enough reason to join me in celebrating Rose Day.

* If you really need to know, Valentine Week’ consists of the following days:

  • 7th Rose Day
  • 8th Propose Day
  • 9th Chocolate Day
  • 10th Teddy Day
  • 11th Promise Day
  • 12th Kiss Day
  • 13th Hug Day
  • 14th Valentine’s Day
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Liver, anaemia and the work of William Murphy

Today we celebrate the birthday of William P Murphy (6 Feb 1892 – 9 Oct 1987), the American physician who received the Nobel Prize for Physiology or Medicine in 1934, together with George Minot and George Whipple, for work done towards the treatment of pernicious anaemia by means of a diet of uncooked liver.

Chicken liver (© All Rights Reserved)
Chicken liver – richer in iron but lower in Vitamin B12 than beef or lamb. I’d rather have it fried, thanks!
(© All Rights Reserved)

Murphy’s initial research involved bleeding dogs to create anaemic conditions in the animals (not a nice thought!), and then treating them with various diets, one of which was a diet of uncooked liver. The discovery that liver helped to relieve anaemia prompted further research into liver by Murphy, Minot and Whipple, and it was found that it contained iron, and that the iron was largely responsible for curing anaemia from bleeding.

Experiments with intramuscular injections of liver extract to treat pernicious anaemia led to further discoveries – it was discovered that in this case the active ingredient was not the iron, but a water-soluble substance later identified as Vitamin B12.

This new knowledge, and the discovery that raw liver and its extracts could be used to treat anaemia, were major advances in medicine at the time.

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Striving for the holy grail of accurate weather forecasting

It’s Weatherman’s Day today. Or Weatherperson’s Day, to be more politically correct. Celebrated mainly in the US, today is the day to recognise people working in the field of meteorology and weather forecasting – those people partaking in the massive task of trying to forecast the weather patterns which, let’s face it, are getting more and more crazy and chaotic each year. The date of 5 February was chosen because it is the birthday of John Jeffries, one of the first weather observers in the US – he collected daily weather data from 1774 to 1816.

Weatherperson’s Day links up thematically with World Meteorological Day that we celebrate in May, but where that day focuses on the weather itself, today we focus on those working to forecast it.

Rain! They said it was going to RAIN! (© All Rights Reserved)
Rain! They said it was going to RAIN!
OK, so the weather forecasters don’t always get it right…
(© All Rights Reserved)

From predicting whether it’s going to rain tomorrow, to developing seasonal weather forecasts, weather forecasting is a hugely complex and computationally intensive endeavour. As such, weather services are often some of the main users of supercomputers around the world. Weather forecasting activities include gathering raw weather data, analysing the data and developing intricate computer models to simulate natural weather systems. One of the (many) challenges of weather modelling is that natural weather and atmosphere systems are near-chaotic – small changes in boundary conditions can result in huge changes in outcome.

These difficulties, however, do not deter the good guys and gals at weather services around the globe who continually strive for more accurate and more timely weather forecasting. According to the US National Weather Service, for example, “lead time for flash flood warnings improved from 22 minutes in 1993 to 78 minutes in 2008. Accuracy over the same time period increased from 71 percent to 91 percent. Lead time for tornado warnings has increased from 6 minutes in 1993 to 13 minutes today. Tornado warning accuracy increased from 43 percent to 72 percent. Winter storm accuracy in 2008 was 89 percent with an average lead time of 17 hours. Since 1990, the Tropical Prediction Center’s 24 to 72 hour tropical storm forecast track errors have been reduced by more than 50%.”

These improvements are quite significant, and can potentially be the difference between life and death for communities in the path of an extreme weather event.

So spare a thought today for all the weather people through the ages who have dedicated their working lives to the holy grail of accurate weather forecasting. After the scorchingly hot, dry weather we’ve had for weeks now, they predicted rain for this week, and lo and behold, it has rained! 🙂

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Debunking myths on World Cancer Day

Today, 4 February, is World Cancer Day, the international day to raise awareness about cancer. This is a little confusing, since later in the year we also celebrate Daffodil Day, which has a very similar goal. Considering the impact of cancer on the human race, however, I suppose this is one topic that deserves a couple of days in the year.

Cancer prevention strategies can include some very basic, everyday tips, like promoting the use of sunblock before venturing into the sun.
Cancer prevention strategies can include some very basic, everyday tips, like promoting the use of sunblock before venturing into the sun.
Note: The yellow Livestrong wristband is a popular symbol, and fundraising item, of the Livestrong Foundation (formerly the Lance Armstrong Foundation until it changed it’s name folliowing Armstrong’s doping scandal in late 2012). Despite the famous cyclist’s recent fall from grace, there’s no denying the huge contributions made during his professional career, towards cancer research and awareness creation, as well as providing support and inspiration for many living with cancer.
(© All Rights Reserved)

There is a minor focus difference between World Cancer Day and Daffodil Day – where the latter has a specific focus on raising funds to support cancer research, World Cancer day is all about awareness creation, and busting some of the myths that still exist around the disease.

Specifically, the World Cancer Day website lists 4 common cancer myths, ranging from general societal misconceptions to very personal issues:

Myth 1: Cancer is just a health issue

Truth: Cancer is not just a health issue. It has wide-reaching social, economic, development, and human rights implications.

As such, it is critical that interventions addressing the prevention and control of cancer need to be included in the wider post-2015 global development goals. By spreading the responsibility to address cancer control beyond the health sector, there is a better chance that all the relevant challenges (at individual and community level) can be addressed.

Global policies, however, are not enough – real investments are needed as part of national, country specific cancer control interventions.

Myth 2: Cancer is a disease of the wealthy, elderly and developed countries

Truth: Cancer is a global epidemic. It affects all ages and socio-economic groups, with developing countries bearing a disproportionate burden.

This is a no-brainer, really – cancer does not discriminate. If anything, the poor and disenfranchised are hit harder by the disease, and more often than not get sicker and die sooner as a result of cancer. Therefore cancer prevention and control policies and funding must be equally non-discriminatory, with interventions made available to everyone – rich and poor, young and old, in both the developed and the developing world.

Myth 3: Cancer is a death sentence

Truth: Many cancers that were once considered a death sentence can now be cured and for many more people, their cancer can be treated effectively.

To achieve this, however, strategies need to be put in place to facilitate cancer control measures such as breast and cervical cancer screening, as well as improved access to cancer services including medicines and other treatment solutions such as radiotherapy.

Myth 4: Cancer is my fate

Truth: With the right strategies, a third of the most common cancers can be prevented.

Of all treatment strategies, prevention remains the most cost-effective way of reducing the global cancer burden. This not only includes putting in place early detection systems, but also implementing programmes that reduce the level of exposure to risk factors and promoting healthy lifestyle choices.

Another critical prevention strategy is improved knowledge dissemination – helping people understand the risk factors as well as ways of addressing these.

More info

For more information on the above myths about cancer and its control and prevention, have a look at the fact sheets prepared by the Union for International Cancer Control (UICC). General background information on World Cancer Day 2013 and the UICC is available here.

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George Miller, human memory and the magical number seven

Today we commemorate George A. Miller (3 Feb 1920 – 22 Jul 2012), an American psychologist, and one of the founders of modern cognitive psychology, and recipient of a National Medal of Science in 1991.

Miller contributed to the establishment of psycholinguistics as an independent research field in psychology. He studied the production and perception of speech, and later shifted his research focus to human memory.

Can you remember phone numbers with more than 7 digits? The argument that the average person isn't able to remember more than 7 digit numbers is an incorrect assumption drawn from George Miller's research on human memory.(© All Rights Reserved)
Can you remember phone numbers with more than 7 digits? The argument that the average person isn’t able to remember more than 7 digit numbers is an incorrect assumption drawn from George Miller’s research on human memory.
(© All Rights Reserved)

He published a classic paper on memory recall (one of the most highly cited papers in psychology), entitled “The Magical Number Seven, Plus or Minus Two: Some Limits on our Capacity for Processing Information” (1956). The paper addresses the limits of human information processing and recall abilities.

Miller basically finds that the number of objects a person can recall in short term memory to be approximately 7. Similarly, in a ‘one-dimensional absolute-judgment task’, where a person is presented with a series of stimuli (different sound tones, for example) and has to respond to each stimulus with a pre-learned response, people can on average relate around 7 (plus or minus 2) stimulus-response pairs.

Since this article, many other cognitive numeric limits have been suggested, and these limits have been refined based on age, the complexity of the objects to be recalled, etc. Miller’s article, however, continues to be one of the most often referred to, and its reference to the ‘magical number seven’ have been used in various contexts, including the the argument that phone numbers should not exceed 7 digits, as this is the largest number people can comfortably remember. (This is one of the many examples where Millers results have been misappropriated, as the recall of phone numbers tend to be more of a long-term memory function, while Miller’s article referred to short-term (‘immediate’) memory.)

Based on his contributions to the field of cognitive psychology, Miller has been rated as one of the top 20 most eminent psychologists of the 20th century.

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Caring for wetlands takes care of water

Today, 2 February 2013, is World Wetlands Day, the first of the big water celebrations of the year forming part of the 2013 United Nations International Year of Water Cooperation.

The 2013 theme is ‘Wetlands and water management’. The slogan is ‘Wetlands take care of water’, which succinctly positions wetlands as a key component in environmental water management programmes, and explains why taking care of wetlands form an essential component in the delivery of sustainable water management. As stated by Anada Tiega, Secretary General of the Ramsar Convention on Wetlands, “It is well recognized that access to a clean and adequate water supply is critical for human survival. Less well understood is that wetlands, as defined by Ramsar, are fundamental regulators of water regimes. Without adequate management of wetlands from the mountains to the sea there is no water of the right quality and quantity where and when it is needed.”

A wetland, dominated by wire rush and sphagnum moss, between Lake Manapouri and Lake Te Anau in the Southern Otago region in New Zealand. The unique wetlands in the Te Anau area were used for the 'Dead Marshes' scene in Sir Peter Jackson's Lord of the Rings movie.(© All Rights Reserved)
A wetland, dominated by wire rush and sphagnum moss, between Lake Manapouri and Lake Te Anau in the Southern Otago region in New Zealand. The unique wetlands in the Te Anau area were used for the ‘Dead Marshes’ scene in Sir Peter Jackson’s Lord of the Rings movie.
(© All Rights Reserved)

The role of wetlands in water management is well explained in the ‘Wetlands Take Care of Water’ information leaflet, available online in PDF format. Given the importance of wetlands in regulating water regimes, one of the worrying facts stated in the booklet is that “Impacts from changes in land use, water diversions, and infrastructure development continue to drive the degradation and loss of wetlands.” It is because of this that there is an urgent need to communicate the importance of wetlands as an essential element of water infrastructure – they are water providers, serving as water filters and purifiers. To continue supplying filtered and purified water, however, they need a continued input of water to maintain the system, and if water is dammed up or diverted for other uses, these critical components in the earth’s water system dry up and disappear. To address this within the wider water crisis facing the world’s growing population, “There is a need to place water at the heart of the green economy and to recognise that working with wetlands as water management infrastructure can be a cost-effective and sustainable way of meeting a diversity of policy, business and private objectives.”

Do you know where your nearest wetland is? And when last did you pay it a visit? Take today to appreciate these wonders of nature. Learn about them, and share your knowledge with those you know. The more people know about and understand the critical role wetlands play, the better the chances that these natural water purifiers may be maintained for future generations.

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Evaporated milk, courtesy of Gail Borden

Cooking time again, as our subject for today is evaporated milk. It was on this day in 1851 that Gail Borden came up with the idea to condense milk through evaporation, after seeing fruit juice being condensed using vacuum pans. He worked tirelessly on the concept, and eventually received a patent for his milk condensing process in 1856.

Created by evaporating the bulk (about 60%) of the water from fresh milk, evaporated milk differs from condensed milk in that the latter has sugar added to help inhibit bacterial growth. Since evaporated milk does not contain added sugar, it has to be homogenised and sterilised to ensure a long shelf-life.

Evaporated milk - still a trusty old stalwart in many a pantry. (© All Rights Reserved)
Evaporated milk – still a trusty old stalwart in many a pantry.
(© All Rights Reserved)

Initially evaporated milk and condensed milk gained popularity at a time when storage and transport of fresh milk was problematic – it could be kept fresh without refrigeration much longer than fresh milk. When water was added back into the evaporated milk it was basically the same as fresh milk, with all the calcium and other nutrients intact, and without the sweetened taste of condensed milk. Interestingly, it was originally thought that it was the condensing of the milk that stabilised it, and only later did it become clear that it was in fact the heating process (to evaporate the water) that killed the bacteria that caused fresh milk to spoil.

Today, with pasteurisation allowing much longer shelf life for milk (even without refrigeration, in the case of long-life milk) the usefulness of evaporated milk as fresh milk replacement has all but disappeared. It is still used, but mainly in cooking, and sometimes as a less rich replacement for cream in deserts. Acknowledging this shift, brands such as Nestle are rebranding the product as “cooking milk” in some markets.

While it may not be a critical milk substitute anymore, evaporated milk remains so useful in the kitchen that you really should always have a can tucked away in the back of the pantry – just in case you need some to spruce up a creamy dessert, soup, sauce, or even a nice casserole or stew.

Related article:
Celebrating Gail Borden and Sweetened Condensed Milk