Predictors of sunbathing and sunscreen use in college undergraduates.

Sunbathing and sunscreen use, as well as related intentions, attitudes, beliefs, and knowledge, were assessed in 90 Southern Appalachian undergraduates. A large majority (75%) reported sunbathing, with more than half reporting sun lamp use. A slight majority (56.7%) reported some use of sunscreen. Subjects reporting an intention to tan spent more time sunbathing, both outside and under a sun lamp. Individuals reporting a sun protection intention had lighter tans and spent less time sunbathing. Sunbathing was predicted by perceptions of sunbathing as relaxing, while sun lamp use was predicted by more positive views of suntans. Sunscreen use was predicted by more positive sun protection attitudes and less negative sunscreen attitudes.

Destabilizing effect of proline substitutions in two helical regions of T4 lysozyme: leucine 66 to proline and leucine 91 to proline.

A class of temperature-sensitive (ts) mutants of T4 lysozyme with reduced activity at 30 degrees C and no activity at 43 degrees C has been selected. These mutants, designated "tight" ts mutants, differ from most other T4 lysozyme mutants that are active at 43 degrees C, but only manifest their ts lesion by a reduced halo size around phage plaques after exposure of the growth plates to chloroform vapors. For example, in the series of T4 lysozyme mutants at position 157, the original randomly selected mutant, T1571, is the least stable of the series, yet, apart from the halo assay and subsequent in vitro protein stability measurements, this mutant is indistinguishable from wild type (WT) even at 43 degrees C. Two mutants were identified: L91P and L66P. Both insert proline residues into alpha-helical regions of the WT protein structure. The stabilities (delta delta G) as determined by urea denaturation are 8.2 kcal/mol for L91P and 7.1 kcal/mol for L66P. CD spectra indicate that no major conformational changes have occurred in the mutant structures. The structures of the mutants were modeled with a 40-ps molecular dynamics simulation using explicit solvent. For L91P, the reduction of stability appears to be due to an unsatisfied hydrogen bond in the alpha-helix and to a new buried cavity. For L66P, the reduction of stability appears to be due to a disruption of the interdomain alpha-helix, at least two unsatisfied hydrogen bonds, and a newly formed solvent-filled pocket that protrudes into the hydrophobic core, possibly reducing the stabilizing contribution of a partially buried intrachain salt bridge.

Rocketborne cryogenic (10 K) high-resolution interferometer spectrometer flight HIRIS: auroral and atmospheric IR emission spectra.

A Michelson interferometer spectrometer cooled to 10 degrees by liquid helium was flown into an IBC class III aurora on 1 April 1976 from Poker Flat, Alas. The sensor, HIRIS, covered the spectral range 455-2500 wave numbers (4-22 microm) with a spectral resolution of 1.8 cm(-1) and an NESR of 5 x 10-12 W/cm2 scrm(-1) at 1000 cm(-1). An atmospheric emission spectrum was obtained every 0.7 sec over an altitude range of 70-125 km. Atmospheric spectra were obtained of CO2 (nu3), NO (Deltanu = 1), O3 (nu3) and CO2 (nu2). Auroral produced excitations were observed for each band, this being the first known measurement of auroral enhancements of O3 (nu3), 9.6 microm, and CO2 (nu2), 15 microm, emissions.

Development of infrared interferometry for upper atmospheric emission studies.

This paper is a review of the historical development of the Michelson interferometer into modern-day Fourier transform spectrometry (FTS) used for upper atmospheric emission studies in the near IR. For the period of the last decade, the focus of the review is upon USAF/USU interferometric instruments. Michelson invented the "cross beam" interferometer in 1880; however, the first interferogram was not reported until that of Wood in 1911. Fellgett deduced the multiplex advantage in 1949. By the early 1950s, both Jacqui-not and Rupert had pointed out the throughput advantage, and Fellgett and Strong had each obtained Fourier transforms of interferograms. In 1959, J. Connes and Gush obtained a spectrum of the nighttime IR airglow in 30 min using a Michelson interferometer. In 1962 Gush and Buijs flew an interferometer aboard a balloon to obtain spectra from the airglow. Mertz and M. Block developed a commercial Michelson interferometer in about 1959. L. Block of AFCRL flew a Michelson interferometer aboard a satellite in 1962. In 1965, Connes and Connes obtained high-resolution spectra of planets using cat's-eye retroreflectors coupled with an interferometrically controlled step and integrate method. NASA successfully flew an interferometer aboard a satellite in 1969, which led to including FTS experiments on the planetary probes. In 1965 Tukey and Cooley published their FFT computer program based upon the algorithm of Good. AFGL/USU applied the FFT algorithm to FTS that same year. Stair launched a rocketborne liquid-He cooled interferometer in 1976 which obtained spectra of earth limb emissions. Mertz in 1959 approached field-of-view widening of an interferometer using variable thickness glass compensator plates. Baker and his USU staff used the Connes-Bouchareine compensation method to develop a series of wide-angle Michelson interferometers (WAMIs) for airglow and auroral studies. In 1973, they created a cryogenic WAMI to obtain an IR airglow spectrum in only 10 sec. A rocketborne version was successfully flown to obtain airglow spectra in 1979. This instrument took a 2-cm(-1) interferogram in 1 sec., used a liquid-He cooled detector to cover the 2-8-microm range, and the NESR was 3 x 10(-13) W cm(-2) sr(-1)/cm(-1) at 5 microm.

Aurorally enhanced infrared emissions.

Aurorally enhanced IR emissions in the 2.9-microm region have been measured from a jet aircraft with a zenith looking radiometer. Overtone chemiluminescent emission from chemically produced NO is the postulated source.

Aircraft Observations of the Infrared Emission of the Atmosphere in the 700-2800-cm(-1) Region.

Atmospheric emission spectra in the 700-2800-cm(-1) region have been measured from an aircraft at 9.45-11.89-km altitudes. All measurements were made viewing at the zenith at a spectral resolution of 2 cm(-1). The measurements were obtained using interferometer spectrometers, and the atmospheric radiation was modulated with a liquid nitrogen cooled chopper that eliminated the thermal emission of the spectrometers from the measured spectra. Essentially all the features of the spectra can be identified with known constituents of the atmosphere. The comparison with a theoretical emission calculation using a tropical atmospheric model was satisfactory except for the H(2)O that showed a smaller concentration by a factor of 5 than was assumed in the model at these altitudes.

Infrared Chemiluminescence of the Reaction N + O(2) ? NO + O.

The chemiluminescent nature of the reaction N + O(2) ? NO + O followed by N + NO ? N(2) + O has been investigated in the steady state through detection of characteristic infrared radiation emitted by NO molecules. Both Deltaupsilon = 1 radiation at 5.4 micro and Deltaupsilon = 2 at 2.7 mu exhibit linear dependence on O(2) pressure. In the case of the overtone, low-resolution spectra are obtained at several O(2) pressures, and it is shown that under the experimental conditions reported here the spectra should closely reflect the initial vibrational distribution of the NO molecules as they are formed. From the spectral results we are able to estimate an overtone quantum efficiency for the reaction N + O(2) ? NO(double dagger) + O. Depending upon the experimentally reported value of the rate for this reaction, the quantum efficiency is between 0.2 and 0.5.