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The results of our earlier studies of reflection and absorption in various spectral regions are reviewed and then used to provide values of the complex index of refraction l• = n + ik of water at 27øC in the spectral range 5000-10 cm -x, corresponding to wavelengths in the range 2 #m to 1 mm. Values of n, k, and the Lambert absorption coefficient a, which are presented graphically and in tabular form, should prove useful in studies of the scattering of infrared radiation by water droplets in the atmosphere and in studies of radiative heat balance at water surfaces. Although the infrared spectrum of water had been the subject of numerous investigations, Irvine andPollack [1968] made a critical survey of published results that revealed many inconsistencies and a general paucity of quantitative data on which to base values of the real and imaginary parts of the complex index of refraction • = n + ik. In view of the importance of n and k in calculations of the transmission, scattering, and absorption of electromagnetic radiation by water droplets in the earth's atmosphere, our laboratory group has devoted considerable attention to the quantitative determination of the optical properties of water in the infrared. We have based our earlier listings of the optical constants n and k on quantitative measurements of various types in various spectral regions. The purpose of the present paper is to give a critical small k and agreed, within the stated limits of uncertainty, in the centers of absorption bands where k is large; in the spectral range v < 600 cm -• the uncertainties in k became larger because of limitations imposed by the spectrometers employed. The values of k were measured in this lowfrequency region by Robertson et al. [1973], who used a far infrared grating instrument to determine a in the spectral range between 800 and 50 cm-•; these authors also obtained values of n by means of a KK analysis of measured values of a. In the spectroscopy of the remote infrared, interferometers used with Fourier transform techniques have marked advantages over conventional grating instruments. Using interferometric methods, John Chamberlain and his associates at the National Physical Laboratory (NPL) have obtained values of review of our earlier studies with the purpose of providing a set n and k in the range 100-20 cm-X; in the course of this work, of 'best values' for use in atmospheric studies. Davies et al. [1970] employed absorption techniques, and Zafar In our initial study, covering the 5000-to 400-cm -x region, et al. [1973] employed reflection techniques. Existing water Querry et al. [1969] attempted to measure the reflectance of data in the microwave and radiofrequency regions have been polarized radiation at two large angles of incidence and to summarized by Ray [1972]. determine n and k by solution of the generalized Fresnel equations. In the range 5000-330 cm -x, Rusk et al. [1971] PRESENT STUDY employed reflectance measurements at near-normal incidence In preparing the present summary of our work on water we and...

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White button mushrooms (Agaricus bisporous) are a potential breast cancer chemopreventive agent, as they suppress aromatase activity and estrogen biosynthesis. Therefore, we evaluated the activity of mushroom extracts in the estrogen receptor-positive/aromatase-positive MCF-7aro cell line in vitro and in vivo. Mushroom extract decreased testosterone-induced cell proliferation in MCF-7aro cells but had no effect on MCF-10A, a nontumorigenic cell line. Most potent mushroom chemicals are soluble in ethyl acetate. The major active compounds found in the ethyl acetate fraction are unsaturated fatty acids such as linoleic acid, linolenic acid, and conjugated linoleic acid. The interaction of linoleic acid and conjugated linoleic acid with aromatase mutants expressed in Chinese hamster ovary cells showed that these fatty acids inhibit aromatase with similar potency and that mutations at the active site regions affect its interaction with these two fatty acids. Whereas these results suggest that these two compounds bind to the active site of aromatase, the inhibition kinetic analysis indicates that they are noncompetitive inhibitors with respect to androstenedione. Because only conjugated linoleic acid was found to inhibit the testosteronedependent proliferation of MCF-7aro cells, the physiologically relevant aromatase inhibitors in mushrooms are most likely conjugated linoleic acid and its derivatives. The in vivo action of mushroom chemicals was shown using nude mice injected with MCF-7aro cells. The studies showed that mushroom extract decreased both tumor cell proliferation and tumor weight with no effect on rate of apoptosis. Therefore, our studies illustrate the anticancer activity in vitro and in vivo of mushroom extract and its major fatty acid constituents.