will be introduced into E. coli, which will in turn be given to mice to test its ability to produce disease. A third experiment will test whether the presence of foreign DNA in E. coli confers any selective ad vantage. Bacteria that have been ge netically altered in various ways will be fed to germ-free animals. A later check of the animals' intestinal flora will reveal whether one type has overpowered the others. Π
Guayule could be U.S. natural rubber source The guayule plant, cultivated briefly in California during World War II as a potential source of natural rubber, may be about to make a comeback. Last week, a National Research Council report recommended that the U.S. initiate a research and develop ment program leading to commer cialization of rubber from guayule and that it collaborate with ongoing Mexican research in this area. Al ready bills have been introduced in Congress to set up a $60 million, five-year research program on the plant. Guayule (pronounced why-oo-lay) is a desert shrub native to the south western U.S. and northern Mexico that produces polymeric isoprene essentially identical to that made by hevea rubber trees in Southeast Asia. As recently as 1910 it was the source of half of the natural rubber used in the U.S. Since 1946, however, its use as a source of rubber has been all but abandoned in favor of cheaper hevea rubber and synthetic rubbers. How ever, the NRC report concludes, de mand for natural rubber is expected to produce shortages of that material as early as 1980 and rubber prices are expected to double by 1985. Natural rubber is required for many kinds of tires and amounts to about 35% of U.S. rubber use.
Guayule was grown as dryland crop on trial basis during 1940s in California
Guayule can be grown domestical ly, whereas all hevea rubber must be imported, making guayule develop ment potentially important to the U.S. economy and security, the report points out. (The U.S. imported $560 million worth of natural rubber last year.) A further reason to develop guayule as a rubber source, according to the report, is that it can be grown on arid lands, including Indian res ervations, where an agricultural cash crop could have important economic benefits. Both the NRC report and the bills before Congress focus on the need for research into guayule cultivation and processing. The legislation, proposed by Sen. Pete V. Domenici (R.-N.M.) and Rep. George Brown (D.-Calif.), would set up a technology transfer and research effort on the plant within the Agricultural Research Service. Π
Number of engineering graduates drops again The number of engineering graduates in the U.S. still dropped in 1976—1% from 1975 in both the total and chemical engineering at the bache lor's degree level. So finds the latest survey of 281 engineering colleges and universities by the Engineering Manpower Commission of the Engi neers Joint Council. However, the 1976 chemical engi neering class of 3146 may represent the end of the decline, at least at the bachelor's degree level. The reason is the large increases in new chemical engineering enrollments that began in 1973 (C&EN, May 17, 1976, page 6). Through 1976, the slippage in new bachelor's degree chemical engineers had run for six straight years since the peak of 3730 in 1970. New bachelor's degree chemical engineers in 1976 held steady at 8% of all engineering graduates. Total bachelor's degree graduates in all engineering fields in 1976 were 37,970, 14% below the last peak of 44,190 in 1972. At the master's degree level, the number of chemical engineering graduates went up 2% in 1976 from 1975 to 1072. Total engineering graduates with master's degrees in creased 1% to 16,506. Chemical engi neers also formed 6% of total gradu ates at this level. Chemical engineers were a higher percentage of all engineers receiving doctor's degrees in 1976 at 11%. New graduates with doctor's degrees still declined in 1976 from 1975, 9% in chemical engineering to 333 and 5% in total engineering to 2977.
New ChE grads decline for sixth year in row Thousands 4.U
3.5
ÔT 1970
« 71
ι 72
ι 73
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ι 75
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! Note: New U.S. bachelor degree chemical engineering j graduates. Source: Engineering Manpower Commission/ Engineers Joint Council
These higher degree levels also suffered declines in the first half of the 1970's. The peak year for master's degrees was 1972 in both chemical engineering and total engineering. For doctor's degrees, the largest re cent classes were in 1970 for chemical engineers and 1972 for all engineers. Even though chemical engineering totals have eroded in the past half decade, the commission still holds up chemical engineering as an example of stability. "Chemical engineering has held a remarkably steady course for the past 25 years with slightly more than 8% of all B.S. degrees each year." The commission points out that the ratio of master's to bachelor's degrees in chemical engineering is the highest since the commission took over col lecting these data from the U.S. Of fice of Education in 1968. The ratio of doctorates to bachelor's degrees in chemical engineering has stayed fairly steady during this time. Among all engineering fields, chemical engineering currently ranks fourth in numbers at the bachelor's level behind electrical, civil, and me chanical. At the master's level, chemical engineering comes in fifth with industrial engineering in fourth place. For doctor's degrees, chemical engineering again is in fourth. Π
Portable centrifugal analyzer developed The centrifugal fast analyzer (CFA), which first appeared in clinical labo ratories in 1968, has been greatly re duced in size and improved in capa bility. Until now, however, it has never been portable. The lack of portability was due to a need to keep the analyzer connected to a bulky computer. April 4, 1977 C&EN
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