Institut d'Optique, Palaiseau, France

A physicist hopes that cool techniques could show up quantum effects in 'big' systems.

When I was a postdoc in Bell Labs during the 1980s, many of the ideas stimulating our work in quantum optics came from researchers developing sensors for gravitational waves.

Gravitational waves propagate as distortions in space, and a passing wave is expected to have a subtle influence on the oscillation of a heavy bar, or to change by a fraction the separation of two mirrors.

To minimize the uncertainty in measurements of such effects, researchers developed new concepts for manipulating the quantum fluctuations that affect parameters such as an oscillator's position.

Concepts they invented, such as 'quantum non-demolition measurements' and 'squeezed states', have since been demonstrated (sometimes with my help), but with light beams rather than massive objects.

Detecting quantum effects in 'big' systems has remained an elusive goal, despite experiments moving to smaller masses and higher oscillation frequencies to make the quantum noise larger. The stumbling block has been heat — thermal excitations overwhelm the well-hidden quantum noise.

Here, recent work suggests a way forward. Three papers published last autumn (S. Gigan et al. Nature 444, 67–70; O. Arcizet et al. Nature 444, 71–74; D. Kleckner & D. Bouwmeester Nature 444, 75–78; 2006) each show that the techniques used to measure a micromirror's motion can cool the mirror at the same time, pushing its temperature close to absolute zero.

Such cold micromirrors could well become the first 'heavy-weight' quantum-mechanical objects — and the techniques developed in quantum optics may eventually feed back into the gravitational-wave detectors that got us started.

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College of William and Mary, Gloucester Point, Virginia, USA

A marine scientist marvels at connections between the cold war and slimy mudflat worms.

Having grown up on the coast of New England, my childhood involved a good deal of digging around in the intertidal mud, unearthing things that most people of good sense do their best to avoid — things such as slimy, slithering worms, which often bite or smell bad, or both.

Older but no wiser, I was delighted to come across a recent paper (E. Teuten et al. Mar. Ecol. Prog. Ser. 324, 167–172; 2006) that has cleverly extracted a surprising scientific result from studies of such mudflat worms.

As well as reminding me of my dubious childhood pastime, the work recalls the period in which I grew up, during the cold war, when much of the world lived in fear of the nuclear weapons then being tested. This work takes advantage of one legacy of those tests.

The bomb tests sent into the atmosphere lots of the isotope carbon-14, normally present only at low levels. This bomb carbon-14 subsequently made its way into the oceans, where it became incorporated into plankton. The plankton in turn sank and became part of the coastal mud, providing a home and a food source for marine sedimentary animals.

Mudflat worms are generally believed to ingest wholesale the nondescript sediment in which they live, yet the worms examined in this study contained more bomb carbon-14 than the sediment surrounding them.

Thus, it seems that the worms assimilate from the amorphous goop, material that has been deposited since the cold war and so is younger than the average age of the sediment. Presumably, they do so because the newer material is more nutritious, but how they extract it is unknown.

Makes me want to get back out by the sea with my bucket.

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The University of Tokyo, Japan

A chemist sees a commercial future for designer polymers.

Just over a decade ago, a discovery in polymer chemistry triggered explosive progress in macromolecular engineering. A trio of papers published last year will, I think, help to usher the benefits of this development into industry.

The results concern chemists' ability to grow tailored polymers, which have controllable size and architecture. Such polymers are becoming more and more important as major players in the burgeoning field of nanotechnology.

The original breakthrough was the development of a method known as atom-transfer radical polymerization, which made it easy to grow polymers to design.

The method uses a catalyst containing a transition metal, such as copper. The catalyst interacts with the polymer, turning it briefly into a reactive radical that will bind another monomer. Each molecule grows one step at a time, so producing polymers with uniform properties.

A problem with this method has been the large amount of catalyst needed to drive the reaction — leaving residues that are costly to remove. Two recent papers do away with this concern, cutting the concentration of catalyst required by up to 1,000-fold (W. Jakubowski & K. Matyjaszewski Angew. Chem. Int. Edn 45, 4482–4486, 2006; K. Matyjaszewski et al. Proc. Natl. Acad. Sci. USA 103, 15309–15314, 2006).

Another advance, which takes advantage of an unexpectedly active oxidation state of the catalyst's copper, will allow production of polymers with an ultra-high molecular weight and a narrow molecular-weight distribution (V. Percec et al. J. Am. Chem. Soc. 128, 14156–14165, 2006).

Some chemical companies are already setting up industrial plants to make polymers by atom-transfer radical polymerization. These developments mean that more are sure to follow.

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The Scripps Research Institute, La Jolla, California, USA

A biochemist considers whether protein misfolding plays a part in type II diabetes.

Much of my research is on cellular protein folding, and in particular on how protein misfolding or protein aggregation causes disease. My group has developed therapies for a spectrum of misfolding diseases, most of which are associated with neurodegeneration, such as Alzheimer's.

But we are beginning to appreciate that therapies that affect protein folding could have a role in treating a much wider spectrum of diseases than is currently realized.

A compelling article from Gokhan Hotamisligil and his colleagues at Harvard University (U. Özcan et al. Science 313, 1137–1140; 2006) presents one example. They found that mice that are both obese and diabetic benefit from treatment with drugs that enhance protein folding.

Their experiment was motivated by observations that linked obesity and diabetic insulin resistance to stress in the endoplasmic reticulum (ER), a compartment in cells where a third of all proteins are folded.

The researchers gave their fat, diabetic mice chemicals that enhance protein folding in the ER. The effect was notable: the mice's blood-sugar levels fell, they showed increased glucose tolerance and reduced lipid accumulation in the liver.

This suggests to me that protein misfolding may be at the heart of type II diabetes, the age-related disease for which these mice are a model.

Folding of the insulin receptor is inefficient. So it seems reasonable to speculate that cells could become insulin-resistant because of compromised insulin-receptor folding in the ER.

We may find, as we develop more selective small molecules to enhance ER folding, that we discover other disorders that can be treated in this way.

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