A dynamical system in which repeated measurements on a single particle yield the same mean result as a single measurement of the whole ensemble is said to be ergodic. The ergodic theorem expresses a fundamental physical principle, and its validity for diffusive processes has now been demonstrated.

This evening, Apple announced that Steve Jobs, its legendary leader, has died. Watch his powerful talk “How to live before you die” at 2005 Stanford Commencement Address. In which Jobs urges us to pursue our dreams and see the opportunities in life’s setbacks, including death itself.

Following the failure of a wide range of attempts to solve the crystal structure of M-PMV retroviral protease by molecular replacement, authors challenged players of the protein folding game Foldit to produce accurate models of the protein. Remarkably, Foldit players were able to generate models of sufficient quality for successful molecular replacement and subsequent structure determination.

MS-DOS is 30 years old today. Well, kind of… On July 27 1981, Microsoft bought the rights for QDOS (Quick and Dirty Operating System) from Seattle Computer Products (SCP) for $25,000 and began work on modifying it to meet IBM’s specification. At that time QDOS really did stand for Quick and Dirty Operating System. That’s actually what it was: a basic but serviceable OS good for coding and running programs written in 8086 assembly language – the x86 instruction set.

The prospects of programming molecular systems to perform complex autonomous tasks have motivated many research into the design of synthetic biochemical circuits. Of particular interest to scientists are cell-free nucleic acid systems that exploit non-covalent hybridization and strand displacement reactions to create cascades that implement digital and analogue circuits. In the latest Science issue, Qian and Winfree of Caltech show how such molecular-scale computing devices might be engineered.

Despite decades of research, cancer in all its guises still kills millions of people each year. The good news is that the more we understand about cancer, the more it appears to be avoidable — not just through smarter eating and healthier lifestyle choices but also with vaccines and chemopreventive drugs. However, a formidable set of scientific, institutional and cultural obstacles stands in the way. Recently Nature published very interesting outlook “Cancer Prevention“.