Stories of modern science... from UPI

By JIM KLING, UPI Science Writer  |  Nov. 23, 2001 at 3:16 AM
share with facebook
share with twitter

, Nov. 22 (UPI) --


A study in this week's edition of the journal Science suggests that forest management may hold the key to keeping global warming in check. More trees, it is argued, will remove carbon dioxide from the atmosphere as they grow, thus preventing the gas from causing the 'greenhouse' effect that warms the Earth. The researchers conducted a decade-long study of carbon exchange between the atmosphere and Harvard Forest, a 60-year-old forest stand dominated by northern red oaks. The researchers' results suggest that, in the long term, ecological factors -- not climatic ones -- change carbon balance. The types of tree species in the forest, their growth rate and the age of the forest can all alter carbon uptake. These factors can be influenced by forest management, according to Carol Barford, one of the researchers who now works at the University of Wisconsin-Madison Center for Sustainability and the Global Environment. "What to do about forest management is a complex issue," Barford stresses. "Our results do not lead clearly to any one management recommendation."


Scientists at Northwestern University have designed molecules that could lead to a breakthrough in bone repair, according to a report in this week's edition of the journal Science. The molecules hold promise for the development of a bonelike material to be used for bone fractures or in the treatment of bone cancer patients, and have implications for the regeneration of other tissues and organs. "Recreating natural bone structure at the nanoscale level - the first level of bone structural hierarchy - is what we set out to do with our experiments, and we succeeded," said Northwestern postdoctoral fellow Jeffrey D. Hartgerink. The molecules self-assemble into a three-dimensional structure that mimics the key features of human bone at the nanoscale level, including the collagen nanofibers that promote mineralization and the mineral nanocrystals. The chemical structure of the material helps attract bone cells that then attach to the structure and patch fractures. Similar self-assembling materials could find use in other medical applications and electronics and magnetics, among other fields. "Regenerative medicine is a big frontier," said Samuel I. Stupp, Board of Trustees Professor of Materials Science, Chemistry and Medicine, who led the study. "Ideally we want the body to heal itself, in this case to repair bone by encouraging mineralized material to grow on a fibrous scaffold that the body would interpret as natural."


A new study of cloned cows suggests that they bear none of the drastic abnormalities that have frequently occurred in cloning trials with other animals, according to research published in this week's edition of the journal Science. Effects often include genetic defects, immune system dysfunction, and excess weight. The results shouldn't be taken as a green light to clone human beings, however, because this study conflicts with others that show abnormalities. "Given that (the current research found that) 73% of pregnancies ended in abortion and 20% of the calves died soon after birth, this paper surely confirms that it would be irresponsible to attempt to clone a person," Ian Wilmut, of the Roslin Institute in Edinburgh, UK and co-creator of Dolly the sheep, told the BBC. "It also raises the question of whether there should be widespread use in livestock production until the technique is more efficient," he added.


A new device based on quantum physics could soon make it possible to send absolutely secret messages over long distances, according to a New Scientist report. The device would send photons 'entangled' in a quantum state, making it impossible for an eavesdropper to decipher the message. Current forms of the technology work over only about 15 kilometers because absorption by the fiber optics currently in use causes photons to lose their quantum state. "The work shows that a quantum repeater can be built with tools that either exist today or are under construction," said one of the team, Mikhail Lukin at Harvard University. "My first impression is that this is a very important development towards making quantum communications practical," said Richard Hughes, an expert in quantum communications at Los Alamos National Laboratory.

(EDITOR: For more information on forests, call 608-265-0604; about bones, call 847-491-3115)

Related UPI Stories
Topics: Ian Wilmut
Trending Stories