SCIENCE/TECHNOLOGY CONCENTRATES • Opening 'windows' in fullerene cages allows atoms to enter Theoretical calculations by chemists at Rice University, Houston, suggest a mechanism for opening a "window" in the carbon cage of QQ or other fullerenes that would allow atoms to enter the interior of the hollow molecules [Science, 263, 791 (1994)]. Gustavo E. Scuseria and Robert L. Murry used semiempirical and high-level ab initio calculations to show that, in fullerenes excited to their triplet state, opening a carbon-carbon bond to create nine or 10-membered rings is a relatively low-energy process. They propose that the holes, or windows, in such metastable species may allow the insertion of atoms or small molecules into the fullerene cage more easily than through direct penetration at the center of a pentagon or hexagon. The authors note that Martin Saunders, a chemistry professor at Yale University, and coworkers at Yale and a number of other universities have incorporated noble gases into Qo and C70 by heating fullerenes under very high pressures. Scuseria and Murry suggest that incorporation of the noble gases may occur in fullerenes excited to their triplet state. They also predict that experiments done with a large triplet population of C^ or C70, as would occur under photolysis, should give much better yields of endohedral fullerenes.
• Protein that binds heme designed from first principles, synthesized A team of chemists has, for the first time, designed and synthesized a protein that binds a redox-active cofactor—in this case a heme group—through specific, noncovalent interactions [/. Am. Chem. Soc, 116,856 (1994)1. William F. DeGrado, a chemist with DuPont Merck Pharmaceutical Co., Wilmington, Del., and the University of Pennsylvania Johnson Research Foundation, Philadelphia, and coworkers have been working for a number of years on the design of a family of proteins that adopts a "four-helix bundle" conformation, a structural motif common in natural proteins including some of the cytochromes. Now, DeGrado and collaborators have introduced two histidine residues at specific locations and orientations in their designed four-helix bundle as axial ligands for binding a heme group, the first step toward creating synthetic cytochromes. Using a number of characterization techniques, the chemists demonstrated that they bind heme within the four-helix bundle with a 1:1 stoichiometry. One of the two proteins binds the heme in such a way that its iron is predominantly in the low-spin state. In the other protein, an equilibrium exists with roughly equal amounts of high- and low-spin hemes.
that for men born shortly before the turn of the century. For women in the same age group, the risk of developing cancers not related to smoking is about 30% higher than for those born in the 1890s. Breast cancer incidence rates have climbed steadily. Women born in the 1950s have a 2.7 times greater risk of developing the disease than women born a half century earlier. Article author Devra Lee Davis, epidemiologist at the Department of Health & Human Services, and her coworkers say better diagnosis can explain some, but not all, of the findings. The authors conclude that cancer-causing agents other than tobacco smoke '"have been introduced into the pop ulation in the past several decades/' Because the same cancers have increased in farmers as in the general population of industrialized countries, the authors speculate that "more detailed studies of agricultural exposures might yield important clues about preventable common causes."
• Internet access available at upcoming ACS meeting Beilstein Information Systems GmbH (Frankfurt), a company formed recently to market electronic products of the Beilstein Institute, will provide free Internet access to attendees at the American Chemical Society national meeting March 13-17 in San Diego, enabling them to check their e-mail and perform network searches. The service is being provided to promote formation of the new company, which will develop, market, and support chemical databases and information management systems for scientists and information specialists in the chemical and pharmaceutical industries and in academia. ACS meeting attendees will be able to come to the Beilstein booth (#510) at the exposition and log in to any computer in the world that is connected to Internet. Telnet and Gopher telecommunications protocols will be available for conducting searches. If the service proves popular, Beilstein will provide it at future ACS meetings.
EDUCATION • NSF plans to establish science education 'think tank' in fiscal '94
NSF will establish an Institute of Science Education in fiscal 1994. The institute will enable a selected group of scholars, representing kindergarten through undergraduate-level education and all types of institutions, to examine science, mathematics, engineering, and technical education in a comprehensive, in-depth manner. Estimated annual cost of operating the facility, which will be funded under a cooperative agreement for an initial period of five years, is $2 mil• Cancer risk found higher lion. NSF will evaluate proposals for funding in two phases. for baby-boom generation Parties wishing to be involved with the establishment of the A study published in the Journal of the American Medical Associ- institute may submit a Phase I proposal that sketches essential features of the institute, including a projected budget, ation [271,431 (1994)] finds that a white man of the baby-boom additional sources of support, and brief curricula vitae of generation has about twice the risk of developing cancer as a key personnel. Phase I proposals (deadline April 15) will be man born between 1888 and 1897. Similarly, a white woman reviewed initially, and a subset of proposing parties will be of the baby-boom generation has about one and one half times invited to submit Phase II proposals (deadline July 1). Potenthe risk as a woman born between 1888 and 1897. When cantial proposers should contact Larry E. Suter, program direccers related to smoking are excluded, the age-adjusted differtor for research activities at NSF's Division of Research, ences for men are even more striking. The incidence of cancer Evaluation & Dissemination, at (703) 306-1650. in men born between 1948 and 1957 is three times higher than FEBRUARY 14, 1994 C&EN
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