Articles in 1998

High controversy surrounded the decision by Britain's National Trust, in the summer of 1997, to ban deer-hunting with hounds on its land. That decision was based on a scientific study commissioned to find out the levels of stress suffered by deer when hunted (which, not surprisingly, turned out to be considerable). The results of the study have now been published and will provide a model for investigations into the animal-welfare consequences of other country sports.

Making the most of European collaboration would seem to be sensible as pressures on research budgets intensify. But those with the power to pursue that agenda are failing to do so.

If you've ever tried to touch a leech, you'll know that it responds by bending away from the point of contact. In each body segment, four sensory neurons detect the location of the touch stimulus, then generate a response through a set of motor neurons. Researchers have now worked out how the leech computes the location of the stimulus, and translates this into a response. And they have found that the leech uses simple cartesian coordinates to do this.

Carbon nanotubes are seamlessly rolled sheets of carbon atoms, only a few nanometres across. Remarkable electronic properties were predicted for nanotubes in 1992 — namely that they can be either metallic or semiconducting depending on their diameter and helicity. This has now been confirmed by experiments on single nanotubes. Distorted nanotubes and junctions between different types might be used in nanometre-scale electronic devices such as transistors and electron emitters, early in the next century.

One of the main clues that apoptosis is a ‘programmed’ cell death is the production of ‘chromatin ladders’ — digestion of DNA into regularly sized fragments. The nuclease responsible for this cleavage has now been identified. Found as an inactive form within the cytoplasm, this nuclease is activated by caspase-3 digestion, earning it the name caspase-activated DNAse (CAD). The same group has also identified a protein that binds to, and inactivates, CAD, and the overall picture seems to be that this protein, ICAD (for inhibitor of CAD), releases CAD after caspase-3 digestion.

Pressures are mounting to bring in radical reforms to German universities to reduce bureaucracy and give a boost to scientific research.

Will the Universe perpetually expand, or eventually collapse? Is space flat, or curved? The answers depend on the density of the Universe, and on whether empty space has an energy density. Observations of so called type-1a supernovae in distant galaxies are beginning to hint that expansion is here to stay — perhaps even that it will accelerate in the future.

Kaposi's sarcoma-associated herpesvirus has been detected in every Kaposi's sarcoma biopsy, yet nobody knows how the virus contributes to the tumour-cell formation that is associated with the disease. The key, it now seems, may lie with the so-called G-protein-coupled receptor. This protein is encoded by the virus, and it induces the production of a powerful factor that stimulates the formation of blood vessels to nourish the tumour cells.