Budget pumps

To invent, you need a good imagination and a pile of junk. Thomas Edison
The 12V DC motor drives the top wheel, turning the bottom wheel.
Together they draw water through from right to left.
I always like to have a healthy pile of junk lying around. Recently I've been wondering about low-cost pumps. It struck me that some of the cheapest are those that drive car windscreen washers. I couldn't find a picture illustrating how they work, so I bought one and took it apart. It was as I suspected.

This generic pump cost £9.99 (you can get even cheaper ones without mounting brackets). It's fairly simple: a motor turns a cog that drives another. Together they pull water through. I don't imagine it will last very long if run constantly as it's designed for short bursts. It clearly wouldn't be a good idea to push suspensions through as it looks easy to clog. Live material would be a pain to clean up too. I just need something to circulate water every few minutes though, so it should be fine.

That is all.

Ben's Big Model

Now here's a message I can get behind...

Ben Heavner from the Cornell Department of Biological and Environmental Engineering has been a busy chap and has just published what I believe is his first paper. It's all about the inadequacies of the yeast consensus model1,2 around its representation of sphingolipid metabolism. The overall goal for the model is to capture every single metabolic reaction that occurs in the yeast Saccharomyces cerevisiae. Seemingly we only managed to capture 41/243 reactions in sphingolipid metabolism, and some of them we didn't do very well.
The Hereford Mappa Mundi. People had been working on this
for well over a thousand yonks and it was still crap.