SCItations

As we have witnessed all too recently, chemical warfare is a very tangible concern for many people of the world. The latest large scale attack occurred in Syria only a few months ago with the use of Sarin gas. The news from Syria makes it all the more urgent that scientists find ways to combat the use of chemical weapons. A group of engineers at UC San Diego have done just that using a new kind of structure called “micromachines”. Many chemical weapon agents used in warfare belong to a class of chemicals broadly labeled “organophosphates”. This label is given to molecules that have a generically organic part and a phosphate part. Here is the molecule sarin, with its organic and phosphate parts highlighted: Nerve gasses like sarin are dangerous because of the way the molecules interact with our nervous system. This interaction is highly dependent on the shape, or conformation of the molecule. That is, if we could somehow break up the atoms in the sarin molecule, they w...

There is big news this week from the FDA who has banned the use of trans-fat in the entire food industry. I thought this would be an appropriate time to discuss the different types of fats we see on our food labels, and why the heck trans-fat got the snub. Fatty acids that you and I eat have a couple defining chemical characteristics. One side of the molecule is the fatty part and one side of the molecule is the acid part – pretty convenient. Here is a representation of a fatty acid molecule:    The fatty acid chain as it is called is made up of a long string of carbon and hydrogen atoms. The type of bonds between the carbon atoms determines whether a fatty acid is saturated or unsaturated. The fatty acid above is saturated because the fatty acid chain contains only single bonds between carbon atoms. Another way to think about saturated and unsaturated fats is to talk about the number of hydrogen atoms bonded to the carbon chain. Saturated fats have the maximum nu...

I like a piping hot mug of mint tea as much as the next person but I wouldn’t say I ride the herbal medicine bandwagon. That’s not to say I don’t think natural medicines can be beneficial, I simply wouldn’t know where to start. If you are the type to put flaxseed in your smoothies or take krill oil before bed here’s something you might want to know. The ginseng tea you have been sipping to reduce stress may actually be half alfalfa sprouts. Researchers in Ontario, Canada performed genetic analysis on 44 commercially available herbal supplements from 12 companies in North America and found that most contained something other than what was on the label. The scientists used a process they call “DNA barcoding” which allows them to compare DNA they found in the supplements to a huge database of DNA sequences and the plant species they belong to. DNA barcoding is a relatively young procedure for comparing plant DNA, but the authors of this paper make exciting headway. Th...

Semelparity is one of those words you choose when you’re playing Balderdash. When you see it you immediately know that no one at the table knows the definition or even has a clue about its place in the English language. That is unless you have an absurd number of animal behaviorist friends.  Semelparous organisms are those that have one chance to mate before they die. There are more of these types of organisms that I would have expected (salmon, some spiders, grain plants) but I never would have guessed that a mammal would be semelparous. If you know anything about evolution then semelparity sounds completely ridiculous! Reproductive success is the key to species’ survival. So then why would evolution favor an animal which dies after a single mating event?  This is the question many behaviorists have been asking about animals like the brown antechinus (an-tee-kine-us). The antechinus is a marsupial mammal found in Australia whose male counterparts have only one o...