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To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.addbeh.2008.07.021 Byline: Wolfgang Hannover (a), Jochen Rene Thyrian (b), Kathrin Roske (a)(b), Julia Grempler (c), Hans-Jurgen Rumpf (d), Ulrich John (b), Ulfert Hapke (e) Keywords: Smoking; Smoking cessation; Relapse prevention; Postpartum; Environmental tobacco smoke Abstract: To test the efficacy of an aid to cessation/relapse prevention intervention for women postpartum. Author Affiliation: (a) Ernst-Moritz-Arndt-University Greifswald, Institute for Medical Psychology, Walther-Rathenau-Str. 48, D-17487 Greifswald, Germany (b) Ernst-Moritz-Arndt-University Greifswald, Institute of Epidemiology and Social Medicine, Walther-Rathenau-Str. 48, 17487 Greifswald, Germany (c) Ernst-Moritz-Arndt-University Greifswald, Institute for Methods of the Community Medicine, Walther-Rathenau-Str. 48, 17487 Greifswald, Germany (d) University of Lubeck, Hospital for Psychiatry and Psychotherapy, Ratzeburger Allee 160, 23538 Lubeck, Germany (e) Robert-Koch-Institute, FG22, Seestr 10, 13533 Berlin Germany

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.icarus.2008.09.006 Byline: Bruce W. Hapke (a), Michael K. Shepard (b), Robert M. Nelson (c), William D. Smythe (c), Jennifer L. Piatek (d) Keywords: Photometry; Regoliths; Spectroscopy Abstract: Predictions of two widely-used regolith reflectance models, a numerically exact computer code and an approximate analytic equation, based on the equation of radiative transfer were tested against the measured reflectance of a medium of close-packed spheres, whose properties supposedly can be well-characterized. Surprisingly, the approximate analytic model was a better match to the experimental data than the numerically exact computer solution. Other approximate regolith models were tested briefly with similar results. Discrepancies between the two models and between models and experiment can be explained if the phase functions and albedos of the spheres are not the same as when the particles are isolated. Differences include the absence of the Fraunhoffer diffraction peak, which is an intrinsic assumption of the approximate analytical model but not the exact numerical model, and increased scattering in the mid-range of phase angles, which the approximate analytic model fortuitously describes more accurately than the exact numerical model. These changes may be caused by the close proximity of surrounding particles. If they are taken into account, models based on the radiative transfer equation appear able to quantitatively predict the reflectances of regoliths and other particulate media. Interparticle perturbations are also predicted to cause a coherent backscatter opposition effect in the backward direction that was observed, but its angular width was found to be much larger than predicted by theories for sparsely-packed media. Author Affiliation: (a) Department of Geology and Planetary Science, University of Pittsburgh, 200 SRCC Bldg., 4107 O'Hara Street, Pittsburgh, PA 15260, USA (b) Department of Geography and Geosciences, Bloomsburg University, Bloomsburg, PA 17815, USA (c) Jet Propulsion Laboratory, Pasadena, CA 91109, USA (d) Department of Physics and Earth Science, Central Connecticut State University, New Britain, CT 06050, USA Article History: Received 8 February 2008; Revised 27 August 2008; Accepted 8 September 2008

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.icarus.2008.01.003 Byline: Bruce Hapke Keywords: Radiative transfer; Regoliths; Spectrophotometry Abstract: It is well known that the bidirectional reflectance of a particulate medium such as a planetary regolith depends on the porosity, in contrast to predictions of models based on the equation of radiative transfer as usually formulated. It is shown that this failure to predict porosity dependence arises from an incorrect treatment of the light that passes between the particles. In this paper a more physically correct treatment that takes account of the necessity of preventing particles from interpenetrating is used together with the two-stream approximation to solve the radiative transfer equation and derive improved expressions for the bidirectional and directional-hemispherical reflectances. It is found that increasing the filling factor (decreasing the porosity) increases the reflectance of low and medium albedo powders, but decreases it for ones with very high albedos. The model agrees qualitatively with measured data. Author Affiliation: Department of Geology and Planetary Science, University of Pittsburgh, 200 SRCC Bldg., 4107 O'Hara St., Pittsburgh, PA 15260, USA Article History: Received 13 June 2007; Revised 19 November 2007

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.addbeh.2005.12.016 Byline: Jochen Rene Thyrian (a), Wolfgang Hannover (b), Kathrin Roske (a), Hans-Jurgen Rumpf (c), Ulrich John (a), Ulfert Hapke (a) Keywords: TTM; Smoking; Pregnancy; Postpartum; Cluster analysis Abstract: (a) To describe a population-based sample of women postpartum who smoked before pregnancy on grounds of the perceived advantages and disadvantages of nonsmoking and the self-efficacy not to smoke. (b) To identify grouping characteristics that can differentiate among those women. This could lead to the development of intervention strategies that are of different efficacy depending on the cluster the woman is member of. Author Affiliation: (a) Institute of Epidemiology and Social Medicine, Ernst-Moritz-Arndt-University of Greifswald, Walther-Rathenau-Str. 48, 17489 Greifswald, Germany (b) Institute of Medical Psychology, University of Greifswald, Walther-Rathenau-Str. 48, 17489 Greifswald, Germany (c) Clinic of Psychiatry and Psychotherapy, Medical University of Lubeck, Ratzeburger Allee 160, 23538 Lubeck, Germany

The physics of scattering of electromagnetic waves by media in which the particles are in contact, such as planetary regoliths, has been thought to be relatively well understood when the particles are larger than the wavelength. However, this is not true when the particles are comparable with or smaller than the wavelength. We have measured the scattering parameters of planetary regolith analogs consisting of suites of well-sorted abrasives whose particles ranged from larger to smaller than the wavelength. We measured the variation of reflectance as the phase angle varied from 0.05[degrees] to 140[degrees]. The following parameters of the media were then deduced: the single scattering albedo, single scattering phase function, transport mean free path, and scattering, absorption, and extinction coefficients. A scattering model based on the equation of radiative transfer was empirically able to describe quantitatively the variation of intensity with angle for each sample. Thus, such models can be used to characterize scattering from regoliths even when the particles are smaller than the wavelength. The scattering parameters were remarkably insensitive to particle size. These results are contrary to theoretical predictions, but are consistent with earlier measurements of alumina abrasives that were restricted to small phase angles. They imply that a basic assumption made by virtually all regolith scattering models, that the regolith particles are the fundamental scattering units of the medium, is incorrect. Our understanding of scattering by regoliths appears to be incomplete, even when the particles are larger than the wavelength. Keywords: Photometry; Regoliths; Radiative transfer; Polarimetry

The highest resolution images of Comet 19P/Borrelly show many dark features which, upon casual inspection, appear to be low albedo markings, but which may also be shadows or other photometric variations caused by a depression in the local topography. In order to distinguish between these two possible interpretations we conducted a photometric analysis of three of the most prominent of these features using six of the highest quality images from the September 22, 2001 Deep Space 1 (DS1) flyby. We find that: 1. The radiance in the darkest parts of each feature increases as phase angle decreases, similarly to the radiance behavior of the higher albedo surrounding terrain. The dark features could be either fully illuminated low albedo spots or, alternatively, they could be depressions. No part of any of the three regions was in full shadow. 2. One of the regions has a radiance profile consistent with a rimmed depression, the second, with a simple depression with no rim, and the third with a low albedo spot. 3. The regolith particles are backscattering and carbon black is one of the few candidate regolith materials that might explain this low albedo. We conclude that Borrelly's surface is geologically complex to the limit of resolution of the images with a combination complex topography, pits, troughs, peaks and ridges, and some very dark albedo markings, perhaps a factor of two to three darker than the average 3-4% albedo of the surrounding terrains. Our technique utilizing measured radiance profiles through the dark regions is able to discriminate between rimmed depressions, rimless depressions and simple albedo changes not associated with topography. Keywords: Comets: Surface morphology Surface processes; Photometry; Albedo

A model published previously by the author that describes light scattering from particulate media is modified to include several improvements: (1) a better approximation to the Ambartsumian--Chandrasekhar H-functions that is especially important for particles with single scattering albedos close to 1.00, (2) increased accuracy for anisotropically scattering particles, and (3) incorporation of coherent backscattering. The goal of the original model of being analytic and mathematically tractable is preserved. No new parameters are introduced by the first and second modifications; however, the third unavoidably adds two new parameters: the amplitude and width of the coherent backscatter opposition effect. Several examples are given in which the results of calculations using the original and new models are compared with exact numerical computations. It is shown that a medium composed of complex particles that are large compared to the wavelength can have a coherent backscatter opposition effect (CBOE) that is broad enough to be readily observable. The CBOE multiplies the entire reflectance and not just the multiply scattered component, so that a low-albedo medium, such as lunar regolith, can have a strong CBOE.

Modeling thermal energy transfer in planetary regoliths involves treating four processes: visible radiative transfer, thermal radiative transfer, conductive transfer, and heat storage. We explicitly treat these processes while considering time-dependent problems, and we apply this model to the regoliths of the Moon and Mercury. Fitting the model to observational data allows us to constrain the radiative resistivity and thermal inertia parameters of these regoliths and hence constrain their conductivities, thermal extinction coefficients, and average grain sizes. It is also found that water ice would be stable in the polar subsurfaces of both bodies, even in areas which receive sunlight during the day. Key Words: Mercury; Moon; surface; regoliths; radiative transfer.

An interactive approach was utilized to address a multiple-criteria project scheduling problem. The first part of the approach involves the use of the Pareto Simulated Annealing metaheuristic method to produce a large representative sample of non-dominated schedules. The second part involves conduction of interactive search over the sample with the help of the Light Beam Search procedure.

The electromagnetic scattering properties of Solar System regoliths are commonly interpreted using the lunar regolith as a prototype. Hence, a thorough understanding of the reflectance of lunar soil is essential to remote sensing planetary studies. We have measured the linearly and circularly polarized reflectances of samples of lunar soil in order to better understand the nature of the lunar opposition effect. Several independent observations show that the zero-phase peak is caused by both shadow hiding and coherent backscatter in roughly equal amounts. Any radiative transfer model for planetary regoliths must take this dual nature into account. The transport mean free path for photons in the lunar regolith is about 1 [[micro]meter], which is much smaller than the mean particle size.

We present angular scattering measurements of a suite of particulate materials of varying particle sizes and albedos over phase angles of 1 [less than] [Theta] [less than] 70 [degrees]. Our results provide strong support for the hypothesis that coherent backscattering can be an important contributor to the enhanced reflectance seen in planetary regolith materials when observed at small phase angles, commonly known in the planetary science community as the opposition effect. Eight samples were each presented with both senses of linearly and circularly polarized light and the reflectance and the circular polarization ratio as a function of phase angle was measured. The reflectances of the samples varied from 3 to 99%. The circular polarization ratio was observed to increase in all the samples as the phase angle of the observation decreased near 0 [degrees] phase angle. The traditional explanation of the opposition surge, the shadow hiding model, predicts that the circular polarization ratio should decrease as the phase angle of the observation decreases. The more reflective materials exhibit stronger opposition surge amplitudes than the less reflective ones. We find a nonlinear relationship between the slope of the opposition curve measured at 2 [degrees] and the single scattering albedo of the sample which is the opposite of what is predicted by the shadow hiding model for the opposition effect. Our results are consistent with predictions of theoretical models of coherent backscattering from spherical particles and strongly suggest that coherent backscattering is the major contributor to the opposition effect. They provide an explanation of the opposition surges reported in highly reflective particulate media, and also the high albedo icy satellites of outer Solar System, both of which cannot be explained by the shadow hiding model.

We observed selected mutual occultations of Jupiter's satellites in 1990-1991 at four wavelengths and we used the occultation profiles to constrain the areal distribution of selected spectrally active compounds on Io's surface. We performed high speed photometry of Io at four wavelengths while it was being occulted by another Galilean satellite. The wavelengths of the filters that we used for this work were 0.305, 0.345, 0.45, and 0.56 [[micro]meter]. These wavelengths were selected to constrain the areal distribution of sulfur and/or sulfur-bearing compounds and sulfur dioxide (S[O.sub.2]) frost, believed to be the two major surface constituents on Io. During a typical occultation, a Galilean satellite whose spectral properties are well defined passed in front of Io, gradually blocking the sunlight reflected by Io from reaching an Earth-based observer. In the observations reported here the occulting satellite was always Europa. Europa's contribution to the combined signal was removed and the remaining Io occultation brightness variations were compared to curves produced by synthesized occultations that would be expected assuming a two component surface, where one component is an unknown mixture of sulfur bearing materials and the other is S[O.sub.2] frost. We utilized the results of previous IUE derived ultraviolet longitudinal phase angle variation studies (Nelson, R. M., A. L. Lane, D. L. Matson, F. P. Fanale, D. B. Nash, and T. V. Johnson 1980. Science 210, 784-786) which localized the distribution of S[O.sub.2] on Io in longitude. Thus, we were able to vary the distribution of S[O.sub.2] in latitude and produce a synthetic lightcurve based on the reflectance properties of solid S[O.sub.2] and elemental sulfur. This was done by simulating different distributions of sulfur bearing materials and S[O.sub.2] frost on Io's surface and minimizing the difference between the synthetic lightcurve and the observed lightcurve. On Io's trailing hemisphere, we find that the region north of the equator between latitudes 0 [degrees] and 60 [degrees] and between 180 [degrees] and 270 [degrees] longitude to be highest in concentration of S[O.sub.2] frost. It also coincides with the highly reflective 'white areas' seen in the Voyager spacecraft television images. All of the observations reported are of Io's trailing hemisphere.

Measurement of the polarization of light scattered by different types of large-sized artificial particles as a function of phase angle reveals that the scattering obeys the laws of geometric optics but not the laws of physical optics. The spheres exhibit strong forward scattering with a few irregularities that cause backscattering. Phase function of all the particles have two lobes, one corresponding to forward scattering and the other to backscattering. A two-parameter, double Henyey-Greenstein function describes the observed scattering phenomena.

Hapke's photometric model was used to examine the photometric textures of a representative subset of Europa's geologic units. The individual units studied have the same small mean photometric slope angle as the entire disk. Particles found on the surface of units have similar scattering properties with one major exception. The two bright plains regions show differences in their single particle scattering functions. Other studies reveal that ion bombardment could explain Europa's disk-integrated photometric properties.

Psychometric characteristics of the German Process of Change (POC) scale, used to measure alcohol misuse are examined.

The main purpose of the study conducted was to determine the degree of Fagerstrom test for nicotine dependence (FTND) represented in a reduced item solution of FTND, heaviness of smoking index (HSI) and the distribution of the HSI estimated levels of dependence. The results indicate that four items of FTND and HSI represent FTND and FTND and HSI may be considered as valid measures of the urge to smoke and tobacco-smoke-seeking behavior.

A study on whether depression and dependency on nicotine can lead to the confidence in the ability to refrain from smoking is scrutinized. It is concluded that dependency on nicotine and acute depression had an additional effect on the confidence in the ability to refrain from smoking.

We measured the change in reflectance and in circular polarization ratio with respect to phase angle of a suite of well-sorted, highly reflective, aluminum oxide powders for the purpose of understanding the contribution of the coherent backscattering phenomenon to the reflectance phase curves of planetary regoliths. The goniometric photopolarimeter that we used measured reflectance and circular polarization ratio over the range of phase angles from 0.05 [degrees] to 5 [degrees] where it has been suggested that coherent backscattering becomes important. The particle size of the samples varied from 0.1 to 30 [micro]m. The wavelength of the illuminating radiation from a HeNe laser was 0.633 [micro]m. We find that the reflectance at 0.05 [degrees] is weakly dependent on particle size. We measured to good approximation the half-width half-maximum (HWHM) of the phase curves, and we find that there is only a weak qualitative agreement between our experimental results and the theoretical estimates of the HWHM for particles of comparable index of refraction and packing density as predicted by M. Mishchenko (1992, Astrophys. Space Sci. 194, 327-333). For particle sizes that are close to the wavelength of the illuminating radiation we find that Mishchenko's model overestimates the HWHM of the phase curve by an order of magnitude. For particle sizes that are much larger or much smaller than the wavelength of the incident radiation the theoretical model underestimates the HWHM of the phase curve by more than an order of magnitude for the smallest particle sizes and factors of several for the large particle sizes. This disagreement between our experimental data and the predictions from theoretical modeling is not unexpected given the assumptions made in the theoretical models that the particles scatter light like isolated, perfect uniform spheres and that the variation in particle size distribution used by Mishchenko was remarkably small, smaller than that of the well-sieved particle sizes used in our experiment. For all samples the circular polarization ratio increased with decreasing phase angle consistent with the hypothesis that the coherent backscattering process is the principal contributor to the reflectance phase curve near 0 [degrees] for highly reflective, multiply scattering, particulate media. We confirm our previously reported significant opposition surges for powders with sizes 50 times larger and 6 times smaller than the wavelength of the incident light (R. Nelson et al. 1998, Proc. Lurar Planet. Sci. Conf. 29th, Abstract 1146). This suggests that for cases where the wavelength of the incident radiation is much larger than the candidate regolith particle size, the photons behave as if they were interacting with ensembles of particles of size comparable to the wavelength of the incident radiation. For cases where the particle size is much larger than the wavelength of the incident light, the photons appear to be interacting primarily with wavelength-sized cracks, surface asperities, or other irregularities in the regolith particles rather than with the particle as a whole. This work, using sorted powders as planetary surface regolith analogues, has applicability for remote sensing studies of highly reflective planetary regoliths such as might be expected to be found on many the icy satellites of the outer Solar System. Many of these bodies exhibit sharp opposition surges that are most likely due to coherent backscattering. [C] 2000 Academic Press