Blue chips

IBM has announced a tie-up with chip-makers in Taiwan and Germany to jointly research computer memory chips based on phase-change materials.

The materials, whose structures change from crystalline to amorphous when an electric current passes through them, have already attracted the interest of researchers at companies such as Philips in the Netherlands (M. H. R. Lankhorst et al. Nature Mater. 4, 347–352; 2005).

Macronix of Hsinchu and the Munich-based Infineon will now join in a project involving 20 to 25 researchers working full-time at IBM's research labs in San Jose, California, and Yorktown Heights, New York.

Stem-cell start

California biotechnology firm BioDefense, which specializes in homeland-security work, says that it is planning an initial public offering of stock to raise funds for its stem-cell division.

The company adds that its newly founded Stem Cell Research division would specialize in the possible use of embryonic stem cells to treat acute liver disease.

Chief executive David Chin says he believes that stem cells would “allow for the development of an artificial liver”. But the company has given no schedule for its stock offering.

No green light

ExxonMobil's shareholders rejected a motion on climate change at the company's annual meeting on 25 May — although holders of almost 30% of the stock voted for it.

The measure would have mandated a report on how the company planned to deal with the regulations of the Kyoto Protocol in countries where it is in effect, and a study of the feasibility of reducing emissions in the United States.

This was the latest in a series of similar efforts by shareholders at major corporations (see Nature 435, 410–411; 2005).