News and Views Feature

Discoveries of comets that behave like asteroids and asteroids that behave like comets are making us reassess our view of Earth's smallest neighbours.

It is now possible to make clones, or exact genetic copies, of sheep, cows, goats, mice and, probably, humans. This opens the way towards the production of replacement body parts from adult cells.

The latest microscopes provide a new level of sophistication not only in imaging but also for interacting with matter at the atomic scale.

We know how many drugs of abuse – cocaine, heroin and nicotine – work, but less about how they lead to addiction. Studies of the brain-learning systems concerned are addressing the causes of addiction, with the intent of developing better treatments.

The inventor of the term ‘black hole’, John Wheeler, has a gift for memorable phrases. ‘Getting its from bits’ is another of his creations. It refers not to an object, but to a vision of a world derived from pure logic and mathematics. That vision has to a remarkable extent been embodied in modern physics — here is a progress report.

The ability to commit suicide is a fundamental property of animal cells. This overview considers recent progress in understanding the nature of the suicide process and how it is controlled.

One of the most versatile and universal signalling agents in the human body is the calcium ion, Ca²⁺. How does this simple ion act during cell birth, life and death, and how does it regulate so many different cellular processes?

The four large moons of Jupiter form the most coherently organized planetary system known. Over the past two years, the Galileo spacecraft has illuminated both the interconnections between these worlds and the uniqueness of each, challenging theories of moon formation and evolution.

At the beginning of this month, Stanley Prusiner of the University of California, San Francisco, was awarded the Nobel Prize in Physiology or Medicine for his work on the infectious agent that causes spongiform encephalopathies _ the prion. His ‘protein-only’ theory now has many advocates, and the advances that have been made, the questions that remain and the ways in which these could be addressed are discussed in this feature.

Projections of future climate change depend largely on the results of computer models. Such models are becoming increasingly sophisticated, but they do not offer the certainties that policy-makers would like.

Neurons and their networks underlie our perceptions, actions and memories. The latest work on information processing and storage at the single-cell level reveals previously unimagined complexity and dynamism.

A scheme for trapping molecules in strong infrared laser beams has been described theoretically by two chemists. Experimental proof awaits. When it comes, molecular spectroscopy will be transformed.