Chance & Necessity

Iron & Steel

Steel is not pure iron, it contains a small fraction of carbon that transforms the soft pure iron into the much tougher steel. I guess I have known that for a long time. But I have not really thought about how the carbon is incorporated into the crystalline iron. Dissolving salt in liquid water is straightforward. The ions of sodium and chloride just diffuse around in the liquid surrounded by the diffusing molecules of water. This is a liquid solution, a solution of salt in liquid water. Steel is a solid solution, it is carbon dissolved in solid iron.

The economics of life, death and weekend working

The Health Secretary Jeremy Hunt has been going round saying* “At the moment, for example, if you have a stroke at the weekend you are 20% more likely to die. That cannot be right, and that is something every doctor wants to sort out as well.”. This is a rather alarming way of saying that 11.1% of those admitted on a weekday because they have had a stroke are dead within 30 days, whereas 12.9% of those admitted on a weekend die within 30 days. This is from work of Roberts and coworkers.

Tiny tiny origami

My Christmas reading has included a PhD* thesis, I am external examiner for a student at Oxford, and the viva is mid-January. The thesis is on the computer simulations of a model of DNA. The simulations are of what is called DNA origami. Origami is of course folding up a sheet of paper in a precise way, to make a paper plane, paper flower, etc.

Interwoven networks of crystals

This is an animation of a rotating cubic box containing a few thousand molecules. It is from computer simulations by James Mithen, who postdoced with me. Most of the molecules are in one of two different crystals, the yellow ones are in a type of crystal called a face-centred cubic (fcc) crystal, while the green ones are in a different type of crystal called body-centred cubic (bcc). Both are crystals in the sense that the molecules are arranged in a regular lattice but the two lattices are different, for example, in the fcc crystal each molecule has 12 neighbours while in bcc each molecule has 8.

Jelly is bad for our nerves

My Christmas viewing has included (amongst the Strictly, Agatha Christie adaptation, etc) a webinar entitled Fluid Business: Could “Liquid”Protein Herald Neurodegeneration? The webinar is on droplet-like structures inside nerve cells that may be associated with some diseases that kill these nerve cells, such as Alzheimer’s, amyotrophic lateral sclerosis (ALS), etc. The webinar includes short talks by a number of scientists, including a presentation by Peter St George-Hyslop that is based on a very recent paper in Neuron. The report reports a lot of work by a small army of scientists on a protein called FUS. Some mutant variants of FUS are associated with the disease ALS.

Teaching till I drop, and now some chaos

Most of my teaching is in the semester whose teaching weeks ended yesterday — it has been a bit crazy. I was more-or-less completely revising two of the three courses I was teaching, so I was a like a little hamster perpetually running on a hamster wheel of lecture and question sheet writing.

Many genes, simple models

cancer_fit
Next week is the last teaching week of this semester. I have been revising almost from scratch both of my second year courses, which at times has taken most of my waking moments. Most of my teaching is this semester, so I have been crazy busy. But I have had time to add a small new bit to my final-year biological physics course. This is on the fact that many aspects of our bodies, and the diseases that afflict them, are controlled not by a single gene, but by many.

Creating a paper trail to prove an article is on the web

This post is a slight lament at good intentions turned bureaucratic drag. In what we must now call the good old days, the final stages of publishing a scientific paper were free of paperwork. You would just check the proofs of your article, then sit back and wait for it to appear, whereupon your coauthors and you could sit back and bask in a warm glow.

Why oh why did it have to be sausages? Why is it sausages?

This week’s devastating news is the declaration that sausages, bacon, etc cause cancer. Sigh. Why couldn’t it have been cabbage? The news was triggered by a report by the International Agency for Research on Cancer. There is an interesting blog post on this by Cancer Research UK (CRUK).

Maths paper beats physics, with a thousand times as many authors

There has been head scratching over a paper on the Higgs boson with 5,000 authors. That is a lot, think my record is about 12 or so. Five thousand authors means a 29 page long author list, plus 4 pages of actual physics. This does look a bit silly. High energy physics is now done on an industrial scale, but all who contributed need to be credited in the conventional way — on the author list.