NEWS
Scott Wins Wiley Award
Strong Signal from Atomic Oxygen
Peter Scott, a research chemist with the Health Protection Branch of Health and Welfare Canada in Ottawa, has received the Association of Official Analytical Chemists' Harvey W. Wiley Award. The $2500 award annually honors an individual who has contributed significantly to the development of analytical methods for foods, drugs, cosmetics, pesticides, feeds, fertilizers, or environmental contaminants. Scott was recognized for his role in developing TLC, GC, and LC analytical techniques for the measurement of the fungal toxins known as mycotoxins. His studies have led to the discovery of these agents in foods and food crops, including the first determination of Alternaria mycotoxin tenuazonic acid in tomato paste, sub-parts-per-million measures of ergot alkaloids in flour, and the discovery of deoxynivalenol (vomitoxin) in Canadian wheat. Scott received B.A. and M.A. degrees and, in 1961, a Ph.D. from Cambridge University. Following two years as a NATO Fellow at the University of California—Berkeley and a year at the University of British Columbia in Vancouver, Scott joined the Health Protection Branch, Ottawa, in 1965. His latest work centers on increasing the number of trichothecenes, one class of mycotoxins, that can be determined and on identifying toxins from Fusarium moniliforme, commonly found in corn.
Researchers working at Sweden's Lund Institute of Technology have discovered an extremely intense IR emission at 845 nm following a two-photon excitation of atomic oxygen by 226 nm laser light. Marcus Aldén and Ulf Westblom, along with visiting scientist John Goldsmith from Sandia National Laboratory, observed the laserlike signal in hydrogen-oxygen flames and in room-temperature flows of N2O and O2, photolyzed into atomic oxygen by the powerful UV laser light. The same two-photon transition has been used to excite fluorescence for measuring atomic oxygen in flames. However, this new stimulated signal, termed amplified spontaneous emission, competes with fluorescence and photoionization from the excited states. According to Goldsmith, the IR emission is seen "over a wide range of stoichiometries, pressures, and laser intensities." It therefore affects fluorescence and photoionization quantum yields and complicates the measurement of the atomic oxygen data. The researchers hope that this new signal will have diagnostic applications, although they warn that the signal intensity does not always linearly follow concentration and understanding the physical process could prove difficult.
Maple Syrup under Thrip Attack New England's famed sugar maple trees are under attack from the pear thrip, a flying insect only about 2 mm long. Thrips devour young maple leaves, putting trees under stress and lowering the production of sap used to make maple syrup. To identify those regions defoliated by the hungry thrips, University of New Hampshire researchers James Vogelmann and Barry Rock monitored near-IR reflectance spectra gathered by the LANDSAT satellite. "A healthy canopy reflects high levels of 830 nm light, especially with deciduous leaves," says Vogelmann. Infected areas show a large drop in reflectance. By comparing spectra at 830 nm collected during the summer of 1988 with tapes from 1984 (a good year for the maples), the researchers found approximately 190,000 acres in northwestern Massachusetts and southern Vermont that have been severely damaged by the thrips. Estimates of total damage in Vermont alone run as high as 1 million acres. "Trees can refoliate for several years, but ultimately their productivity goes way down," explains Vogelmann. Over two or three seasons, repeated defoliations could even kill the tree. Little is known about these harmful insects. Says Vogelmann, "We can't do anything in terms of predicting what they will do this year."
For Your Information Three recent publications from the National Committee for Clinical Laboratory Standards (NCCLS) should assist the clinical chemist: Protection of Laboratory Workers from Infectious Diseases Transmitted by Blood, Body Fluids, and Tissue: Tentative Guidelines (M29-T); Blood Alcohol Testing in the Clinical Laboratory (TDM6-P, Vol. 8, No. 10); and Preparation and Testing of Reagent Water in the Clinical Laboratory—Second Edition: Tentative Guidelines (C3-T2). For more information, contact NCCLS, 771 E. Lancaster Ave., Villanova, PA 19085 (215-525-2435). The University of Hawaii has established a Biosensor Laboratory under the direction of Garry Rechnitz. Located in the Department of Chemistry, the new facility will concentrate on multidisciplinary research on biosensors. The National Science Foundation has awarded Phase I grants—up to $50,000—to 149 small high-tech firms under its Small Business Innovation Research (SBIR) program. Following this first phase, projects NSF believes could lead to "economically and socially beneficial products" will receive up to $250,000 over two years for continuing research. Materials scientists with the National Institute of Standards (NIST) are developing measurement standards for the production of diamond films. These synthetic materials hold promise for the aerospace, electronics, and equipment industries. For more information, contact Albert Feldman, Optical Materials Group, A329 Materials Bldg., NIST, Gaithersburg, MD 20899 (301-975-5740). ANALYTICAL CHEMISTRY, VOL. 61, NO. 8, APRIL 15, 1989 · 529 A
