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One thing: http://www.gsi.de/forschung/bio/energy_e.html is actually about heavy ions (carbon). The curve is not _too_ different for a proton, though.

For a nice picture of energy deposition vs. depth see e.g. http://www.gsi.de/forschung/bio/energy_e.html
One can adjust the peak energy deposition's depth by varying the proton's energy. The surrounding tissue gets a much lower dose than in X-Ray irradiations.
Combine the particle accelerator with a PET (http://en.wikipedia.org/wiki/Positron_emission_tomography) and you can irradiate a cancer with cubic millimeter resolution.

This is actually not a new, purely academic technique, it is already commercially available, see http://en.wikipedia.org/wiki/Proton_therapy

Attention: I'm not a doctor but a physics student :)

By contrast, accelerated protons deposit their energy almost evenly, at a relatively low rate, until they are slowed to a certain energy, at which point their deceleration rapidly increases, accompanied by a massive increase in linear energy deposition. This leads to the "Bragg Peak", which offers a much, much more accurately targeted beam than is possible with conventional sources. (See this illustration as an example - compare the red line (in this case, C12 ions, but a similar principle) to the green line (an 18MeV photon beam). By carefully tuning the beam energy and orientation this point can be scanned over the tumour volume, giving a very localised dose deposition.

What puzzles me is why this is news - I was under the impression that this concept is well-established, and has been fairly well verified already. Just some fluff to fill up the science and medicine section, maybe? Now if it was about the CERN anti-proton tests, that's certainly something with a more dubious cost/benefit analysis...

* - I say a few assumptions, these are basically the principle ones behind all radiotherapy - that is, that all dose at the end of track structures is created equal and all dose is bad according to the LNT. While these ideas may not be strictly true, it is unlikely for them to be so wrong that it would invalidate the treatment as a whole.

Particle accelerators are used for cancer-therapy and are especially interesting for tumors that are surrounded by lots of healthy tissue, for example a brain tumor. As ions penetrate the tissue they loose only little energy on their way through but as they are stopped they deposit a lot of energy at that point (Bragg peak). This has the advantage that most of the energy is brought to where you actually want to have it, i.e. inside the tumor. The surrounding tissue is damaged far less than using other kinds of radiation (x-rays, etc.).
There has been very promising success with this kind of treatment using carbon ions at the "Gesellschaft fuer Schwerionenforschung", an accelerator facility in Germany. You can find more information here: http://www.gsi.de/portrait/Broschueren/Therapie/in dex_e.html

>The Wikipedia has a "computer bug" entry that lists some other "famous bugs" including the fictional HAL 9000 bug.

Yeah, it lists them, but doesn't really link to good stories -- so...

An error in a single FORTRAN statement resulted in the loss of the first American probe to Venus.

Software reboot during the Apollo 11 landing forced Armstrong to manually land the lunar lander.

An Iraqi Scud missile hit Dhahran barracks, leaving 28 dead and 98 wounded. The incoming missile was not detected by the Patriot defenses, whose clock had drifted .36 seconds during the 4-day continuous siege, the error increasing with elapsed time since the system was turned on. This software flaw prevented real-time tracking. The specifications called for aircraft speeds, not Mach 6 missiles, for 14-hour continuous performance, not 100. Patched software arrived via air one day later.

The Ariane 5 satellite launcher malfunction was caused by a faulty software exception routine resulting from a bad 64-bit floating point to 16-bit integer conversion.

lots more here and here.

Darm, if I'm not mistaken, means 'intestine'. Stadt means city. So this element is Intestine-city-um.

Exactly. AFAIK the city is named after the wriggly litte rivulet Darmbach which is not quite visible any more in the city.

Darmstadt, by the way, is about the geekiest place in old Europe. Seemingly ordinary people may actually understand the print on your T-shirt there. Besides GSI, Darmstadt has a Technical University and a University of Applied Sciences. The European Space Operations Center is located there and the Fraunhofer institutes for Secure Telecooperation, Integrated Publication and Information Systems, Computer Graphics, and Structural Durability. Deutsche Telekom is running a research center there and the headquarters of T-Online are about to move to Darmstadt from the nearby town of Weiterstadt. There is a Linux User Group too. Darmstadt officially carries the title Wissenschaftsstadt (city of science). It is located about 30km south of Frankfurt/Main. The bus ride from Frankfurt airport takes 25 minutes.

Here's a summary of the discussions about these concerns. The article mentions three primary concerns:

• Formation of Mini Black Holes
• Strangelets and Strange Matter
• Vacuum instabilities

Anyway, you'll probably claim I'm just spouting more "technobabble", so read the article (and its references in Scientific American for yourself.

Or you could just take my word for it. I am, after all, completing a degree in particle physics. ;)

Those that are fluent in the german language at least may be interested in checking out the following explanatory file on tunneling:

http://theory.gsi.de/~vanhees/faq-pdf/nimtz.pdf