Quorum Sensing in Bacteria

September 26, 2006

Quorum sensing is the ability of bacteria to communicate and coordinate behavior via signaling molecules. The reason for these systems seem to have evolved is to coordinate behaviours or actions between individual bacterial cells depending on their number. For example, opportunistic bacteria can grow within a host without harming it, until they reach a certain concentration. When their numbers are sufficient to overcome the host’s immune system, they change their behavior and cause disease.

This is a really hot topic in microbiology at the present time, so MicrobiologyBytes has devoted the last two podcasts to it. If you’d like to know more, try:


Face on Mars

September 22, 2006
Face on Mars

The ESA has imaged a face on Mars, but that’s old news. They’ve also imaged the Cydonia region which is home to another face. It’s good news because the region has been difficult to study – not because of alien interference but because of dust storms. That’s part of what makes Mars an interesting place. It’s not as actove as Earth or Io, but it isn’t geologically static either.

Though obviously we can’t rule out alien intervention.

BBC Creative Archives to close

September 22, 2006

If you haven’t seen it yet, there’s only a few days left to browse the BBC Creative Archives as the trial period is coming to an end. The Open Earth Archive contains useful video clips and images which you can edit for your own purposes. For instance the video above it their imagery of Ayer’s Rock. The soundtrack though is mine because I don’t make idle threats. There are many other mathematic constants to nail to a drumbeat, even though I see that MC Kinky has beaten me to another with Everything starts with an e.

Seen Elsewhere

September 18, 2006

Wonder of Phi
Science meets art and both are beaten soundly by maths in this post on the constant Phi, which is a constant and irrational number that keeps cropping up in nature. The video above is Pi rather than Phi, because as far as I know no-one has made a pop song about Phi. Donations in hard currency will ensure I don’t try and write one.

Zoning of the snails at Snail’s Tales.
Aydin Örstan is on a mission to tell the world how interesting snails are. With posts like this it looks a fairly easy task because they are interesting, though his writing helps. This is a post on the adaptability of snails to certain environments. Excellent photography and the rest of his blog is always interesting.

Crop Circle Failure
Phil Plait the Bad Astronomer has found the best quote I’ll read today in a news story on crop circles.

From crop circle designers and top-level researchers to the baffled farmers who usually find them, nobody really knows the origin of crop circles.

Visit his site for more comment.

This is graduate journal “for the discussion of science” from Toronto, which I found out about from Inkycircus. I’ve been reading the article Who Benefits From Science Blogging? [PDF] which leaves plenty of other stuff to read.

Oh and it turns out the climate isn’t changing – it’s just shagged out after a really long squawk. It’s all becoming clear now.

Planet X!

September 14, 2006
Eris and Dysnomia

2003 UB313 has a name! Rather than go for the slighly kooky Xena (the provisional name given it by the astronomers who discovered it, thereby instantaneously confiming all publicly-held stereotypes about such astronomers) the IAU has gone with Eris, the Greek goddess of strife. It has a satellite (provisionally Gabrielle), now named Dysnomia after the daughter of said goddess. Not sure why they went with the Greek names instead of the Roman ones that they used for the other planets. Perhaps it’s a way of further distinguishing it as a ‘dwarf’ planet, as opposed to a ‘real’ planet.

Campaign to change Pluto to Hades?

Homage to Goiâna

September 13, 2006

As it’s salient to the previous entry – coincidentally, today is the 19th anniversary of the Goiâna accident, regarded as one of the worst incidents of the Atomic Age.

If we needed reminding how unpleasant it could be for our future archaeologists were they to crack open the storage chamber containing the nuclear waste, there’s a fairly comprehensive account here (wikipedia, kids, mind your references)


To precis, a couple of chancers found a radiosource in an abandoned hospital and bilked it with the hope of selling it on. It came to a junkyard owner, and the contamination was spread to him and his family. Many people were taken ill, several of whom later died.

The wikipedia account contains lots of interesting data about the spread of the contamination and the clean-up operation that followed – one point of particular note (I think) is that this well-documented incident has been recently cited in models of radiological (‘dirty’) weaponry.

[edit: once again, I’m thwarted by technology – I can’t persuade that link to work because of the funny characters. Some technlogical wizard might know the answer, until then copying and pasting might have to suffice]

 [edit 2: oh, huzzah, it seems to be working now. Thank you Alun!]


September 10, 2006
Out of work no longer? Photo by sculpture grrrl.

There’s an interesting article in the current New Scientist about reverse archaeology. Here’s the problem: The USA has thousands of tons of amazingly lethal waste to dispose of. What they’re going to do build a storage facility and leave the stuff there for 250,000 years. It’s potent stuff and it’s going to be a serious danger for at least the next 10,000 years so it would be helpful to leave a warning. There are a few problems.

One is language. How many people are fluent in Latin, which was a major language till quite recently? What’s your ancient Greek like? How good are your hieroglyphs? These languages have all only existed for a fraction of the time that these warnings need to last. How do you leave a message for the future? Signs are going up in major languages, but the US military have asked anthropologists for help. Their suggestion is pictures, the proposal is two faces, one showing fear and the other disgust. Another is a comic strip of a man digging and then becoming sick.

Once you have your message how to you display it? You need a billboard that will last 10,000 years. Serious and Delirious descibes the plan as ‘Evil Stonehenge’. It does look like the military will be returning to Stone Age technology to hold the message.

The final problem is making sure the message is believed. This could be where it fails. The waste will be under a mound with magnets and radar reflectors, which in a few thousand years time might be the epitome of mystical weirdness. Now at the mysterious keep out signs warning of a deadly curse which must not be disturbed.

Now who wouldn’t want to open that mound pronto?

You can read more on the same project at Wired, via unsane1. You can also read about Cornelius Holtorf’s considerably less noxious Incavation Project via the Wayback machine.