Review, News & Views, Perspectives, Hypotheses and Analyses in 2006

The versatile DNA molecule has found many applications beyond biology. In its latest role, it serves as a self-assembling scaffold to arrange different metal ions in a row, like pearls on a string.

A compact electron accelerator can be made by the cunning use of laser pulses to let electrons 'surf' on a plasma wave. The problem has been controlling exactly how much the electrons are accelerated.

Black holes box at two weights: active galactic nuclei are in the super-heavyweight class, whereas galactic black holes are relative featherweights. But does the same physics pack both objects' punches? It seems that it does.

Are two penises better than one? Not so, implies a study of doubly endowed earwigs. An ancestral behavioural preference for the right penis might have facilitated the loss of the left in species that arose later.

The discovery that parts of a solid helium crystal could flow through other parts without friction ignited physicists' interest. Independent experiments confirm this unusual superflow, but its origin remains mysterious.

The infectious form of the malaria parasite has thousands of proteins, making it tough to develop a vaccine for it. Narrowing down which proteins cause protective immune responses may help resolve the problem.

Satellite data show that phytoplankton biomass and growth generally decline as the oceans' surface waters warm up. Is this trend, seen over the past decade, a harbinger of the future for marine ecosystems?

Embryonic stem cells have great potential in medicine, but the current methods used to grow them prevent their therapeutic use. A dual-action compound has been discovered that may help solve this problem.

Stem cells are increasingly implicated in maintaining certain cancers. Studies of an intractable type of brain tumour provide hints as to why such cells may underlie the tumours' resistance to therapy.

Rare species have to cope not only with habitat loss, genetic bottlenecks and invasive competitors, but also with a self-reinforcing cycle of human greed. This last threat has now been dragged into the spotlight.

How do voltage-gated ion channels in cell membranes open? The latest work suggests that the process depends on having the correct lipid molecules in the membrane, with phosphate groups being mandatory.

Generating human stem cells from a single cell recovered during preimplantation genetic diagnosis does not, in principle, harm the embryo. Can the approach be used in assisted reproductive technology programmes?

Silicon is the archetypal semiconductor, and base material of the microelectronic age. But it turns out that, treated the right way, silicon the semiconductor can become silicon the superconductor.

Molecules in solution change their conformations so quickly that no method has been able to record the process. This looks set to change, as infrared spectroscopy rises to the challenge.

The first map of copy-number variation in the human genome has been created. It is now feasible to examine the role of such genome variation in disease and to explore in depth the extent of 'normal' variability.

Accumulation of organized, self-polymerizing protein aggregates is a hallmark of Alzheimer's disease and infectious prion diseases. The similarities between these conditions may be even closer than that.

In most bacteria, a molecule known as trigger factor prevents misfolding of newly made proteins emerging from their ribosome factory. The dynamic action of this molecule has been followed using fluorescence spectroscopy.

A compound found in red grapes called resveratrol improves the health and lifespan of mice on a high-calorie diet. This is potentially good news for overweight humans. Does it bode well for the rest of us too?