Tuesday, November 27, 2007

Atomium

On one of the bulletin boards outside of our labs someone recently posted a brochure about the Atomium, and it really caught my attention. This interesting-looking building was erected for the International Exhibition of Brussels in 1958 (the World Fair in Brussels). Based on the structure of solid iron (which by the way is body centered cubic) magnified 165 billion times, the Atomium was designed to "embody the audacity of an epoch that seeks to confront the destiny of man with scientific discovery." Though I don't believe the individual spheres of the building are 165 billion times bigger than a real life iron atom (an iron atom is approximately 2.5 Angstroms in diameter x 165,000,000,000 = 135 feet, and the actual building spheres are only about half that size), the distances between the atoms are supposedly magnified to that size.

Visitors are only allowed in 5 of the 9 spheres--the base (Henri Storck sphere), where you will find an exhibit dedicated to the 1950's, the top restaurant sphere, the central (Waterkeyn) snack bar sphere, the sphere named after the Belgian artist Marcel Broodthaers, and the children's only sphere. At 115 feet long, the escalators found inside the tubes of the Atomium are some of the the longest in Europe.

Why make a body centered cubic building modeled after the structure of iron?? It was a tribute to the steel companies that helped to sponsor the construction by providing raw materials.

After seeing these pictures, I really want to visit. Thanks to Mirth (and her family) for the lovely photographs.

Stairs connecting the spheres:

A view to the outside

Artwork inside of the Atomium


Wednesday, November 21, 2007

Motivation

Tuesday, November 20, 2007

Cockroach behavior

There is quite a cockroach infestation in our chemistry building here (although come to think of it, I haven't seen any bugs in at least 6 months, hmmm...), so I was naturally curious when I came across this paper in Science. For a second think back to all of those science fiction movies you watched as a kid (and you probably have seen at least a few if you are a scientist), especially the movies involving robots--in particular robots that were integrated into human society and took on some seemingly human emotions (R2D2 and 3CPO from Star Wars are my all time favorite robots)...Now think about the social integration of robots on a slightly smaller scale (with insects), and that is exactly what José Halloy and coworkers have accomplished.

American cockroaches typically recognize chemical cues from their neighboring cockroach friends, and utilize these signals to act as a group and make self-organized choices. Self organization complements the preexisting environmental signals and coexists with status levels between the insects such as leader/worker relationships. Halloy and coworkers claim to have socially integrated cockroach-sized robots into a cockroach collective. How was this achieved? You guessed correctly--through chemistry! Basically by extracting and characterizing the hydrocarbons found in the cockroaches' exoskeleton, researchers identified compounds that were key in inter-cockroach recognition. By coating the robots in these extracts (which included compounds such as 6,9-heptacosadiene and 3-methylpentacosane), cockroaches accepted these robots and, even more amazingly, allowed the robots to influence decisions made by the cockroach community.

My only question is who got to perform the extraction of the cockroach exoskeleton into dichloromethane? That just sounds pretty icky to me.

Tuesday, November 13, 2007

Ham Flavor?

When I think about all of the artificial flavorings that go into foods, it always makes me feel a little disgusted. Sometimes even the so-called "natural" ingredients creep me out, so I really hate to think what might go in this soda to make it taste like ham. But I do give them credit for a cool (yet slightly disgusting) idea.

For your enjoyment, I've compiled a short list of the some of the more common flavoring molecules below.

Wednesday, November 7, 2007

Flu Vaccine and Thiomersal...

Today I got a flu shot. In my past life, I used to consider people who got such unnecessary vaccinations as "weak," but now I just figure, why not? Who wants to deal with a bad case of the flu, miss work, and possibly end up in the hospital (as I did this summer with a severe case of the stomach flu)? Of course the vaccine doesn't catch all strains of the flu, but hopefully it will at least give me some protection, which is certainly worth suffering through one day with a sore arm.

As I was signing my life away while waiting for the shot (no, I won't sue the school if I have an adverse reaction to the ingredients of the vaccine), the information packet warned that this shot contains thiomersal and that people with known allergies to this preservative should not be getting the shot. We have all heard about the controversy assocaited with vaccines; one side believes that some vaccines might cause autism and other disorders associated with brain development, while the other side does not believe this to be the case. Thiomersal is at the center of this debate.

Looking at its structure, it is easy to see why this compound might be considered suspicious. While it is a powerful preservative because of its antifungal and antiseptic properties, it also is an ORGANOMERCURY compound. Basically one of the reagents that I wouldn't like to work with in lab. You only have to read the story of Prof. Karen Wetterhahn (which was posted for some time in our group's hallway as one of those 'be more careful in lab' warnings) to know why I might refuse to work with alkyl mercury compounds. Basically the harmless sounding name thiomersal actually refers to a compound that probably breaks down to ethyl mercury inside of your body. At the same time, it is a necessary part of the vaccine and works to prevent possible adverse side effects like as bacterial infection that might occur in vaccines lacking preservatives. And is ethyl mercury just as bad as methyl mercury? Apparently not [1], but that doesn't stop parents from worrying about their children.

Personally, I wouldn't be too worried about thiomersal containing vaccines. In general, very few vaccines contain thiomersal any more, and those that do have extremely low levels present. Looking at this table, some vaccines contain 0.01% thiomersal. In studies, levels of thiomersal producing inorganic mercury levels ranging from 201 micrograms/Liter to 50 milligrams/L were shown to be toxic in cell culture, (and, for those interested, these levels induced activation of caspase-3). Levels of thiomersal used under normal vaccination conditions are much much lower. In the worst case scenario, after a complete series of vaccinations a very very small child would receive less than 50 micrograms of inorganic mercury per kg of body weight. Additionally, ethyl mercury (half life of about 18 days in the bloodstream) does not bioaccumulate like methyl mercury (half life of 50 days).

So go ahead and vaccinate your children. And why not get a nice flu shot for yourself while you are at it?

[1] How do I know ethyl mercury isn't near as toxic as methyl mercruy? Of course there have been some scientific studies completed on this very subject, but I also have some firsthand experience. Thiomersal was once sold as Merthiolate. I am not that old yet, but I still can remember back to when my dad would put this bright pink solution on any little cuts or scrapes that I would have. It always stung for a second, but nothing ever got infected. Strange to think that it was actually an ethyl mercury containing product. In 1998 the FDA banned the use of thiomersal in over the counter products, which explains why I haven't been able to find this wonder drug from my childhood in any stores.