Friday, October 19, 2007

Brain Candy

I love The Economist. In every issue, there are at least several articles that make me say "hmmm" out loud. Whenever my wife hears 3 or 4 "hmmm"s in quick succession, she knows I'm about to start reading some obscure facts to her about globalization or Indonesia at a Crossroads. She pretends to be bored, but deep down, I know she's extremely bored.

Anyway, here are a few "hmmm"s from this week's issue:

Explaining one of many delays in the Airbus 380 launch:

"The cabin wiring—more than 330 miles of it and over 40,000 connectors in each aircraft—caused problems because two incompatible versions of computer-aided design software were used. The Germans in Hamburg had one system, the French in Toulouse another. When the electrical harnesses came to be fitted in the forward and aft fuselage sections, many didn't connect with each other. Despite efforts to resolve this, it was decided in October last year that only by updating the computer-design tools would Airbus get on top of the problem. That meant a third delay."

Why 1-day old donated blood is dangerous:

"The main reason for giving a patient blood is that it carries oxygen. It carries lots of other things, too, such as glucose. But it is a lack of oxygen that will kill you quickest. However, as Dr Stamler points out, what determines whether transfused blood works as a treatment is not merely how much oxygen it is carrying, but whether that oxygen can reach the tissues that need it. This is where nitric oxide comes in.
Nitric oxide increases the flow of blood to tissues by dilating the arteries that penetrate those tissues...When a red blood cell reaches any tissue in need of oxygen it releases nitric oxide in order to dilate the capillaries. Only then can it deliver its cargo. And that is doubly true of the cells in stored blood since red blood cells become less flexible with age, and thus less able to squish into capillaries. Dr Stamler thus wondered if a lack of nitric oxide was causing the problems associated with transfusions.
What he and his colleagues discovered, and published this week in the Proceedings of the National Academy of Sciences, was that the amount of nitric oxide in stored blood does indeed decrease—and does so rapidly. Within a day of storage, blood loses 70% of its nitric oxide. After a few days, up to 90% has been lost."