57 research outputs found

    Non-participant observers utilization of the 16PF source traits as role construct repertory test constructs in relation to therapist preference patterns.

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    Dept. of Psychology. Paper copy at Leddy Library: Theses & Major Papers - Basement, West Bldg. / Call Number: Thesis1979 .S673. Source: Masters Abstracts International, Volume: 40-07, page: . Thesis (M.A.)--University of Windsor (Canada), 1979

    DEPRESSION, COGNITIVE DISTORTION AND SELF-EFFICACY IN CHRONIC-PAIN PATIENTS.

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    The purpose of this study was to investigate cognitive distortion, mood change, treatment expectancies and treatment choice in depressed and nondepressed chronic-pain outpatients, and to see whether a persuasive message could influence expectancies about treatment. Thirty patients referred for psychological assessment participated in the study. The Beck Depression Inventory (BDI), the Differential Personality Inventory (DPI), and the MMPI were used to assess depression. Mood change was measured by three administrations of the Profile of Mood States. Bandura\u27s definitions of self-efficacy and outcome expectancy were used to design a measure of expectancies about pain-management treatment. All subjects were provided with assessment feedback having an equal number of positive and negative statements. Measures of cognitive distortion were derived from free recall and from estimation of positiveness of feedback. Half of the subjects were randomly assigned to hear a brief persuasive self-efficacy message prior to feedback. The persuasive message was not effective in changing expectancies. Depressed subjects had lower expectancies regarding treatment and were more negatively biased in the estimation (but not free recall) of feedback. The DPI was the best predictor of expectancies and bias, followed by the BDI. Subjects\u27 moods became more positive over the course of the assessment. Those with positive expectancies were more likely to accept the pain management program.Dept. of Psychology. Paper copy at Leddy Library: Theses & Major Papers - Basement, West Bldg. / Call Number: Thesis1986 .S663. Source: Dissertation Abstracts International, Volume: 47-05, Section: B, page: 2187. Thesis (Ph.D.)--University of Windsor (Canada), 1986

    Calcium in Mercury's Exosphere: Modeling MESSENGER Data

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    Mercury is surrounded by a surface-bounded exosphere comprised of atomic species including hydrogen, sodium, potassium, calcium, magnesium, and likely oxygen. Because it is collisionless. the exosphere's composition represents a balance of the active source and loss processes. The Mercury Atmospheric and Surface Composition Spectrometer (MASCS) on the MErcury Surface. Space ENvironment. GEochemistry. and Ranging (MESSENGER) spacecraft has made high spatial-resolution observations of sodium, calcium, and magnesium near Mercury's surface and in the extended, anti-sunward direction. The most striking feature of these data has been the substantial differences in the spatial distribution of each species, Our modeling demonstrates that these differences cannot be due to post-ejection dynamics such as differences in photo-ionization rate and radiation pressure. but instead point to differences in the source mechanisms and regions on the surface from which each is ejected. The observations of calcium have revealed a strong dawn/dusk asymmetry. with the abundance over the dawn hemisphere significantly greater than over the dusk. To understand this asymmetry, we use a Monte Carlo model of Mercury's exosphere that we developed to track the motions of exospheric neutrals under the influence of gravity and radiation pressure. Ca atoms can be ejected directly from the surface or produced in a molecular exosphere (e.g., one consisting of CaO). Particles are removed from the system if they stick to the surface or escape from the model region of interest (within 15 Mercury radii). Photoionization reduces the final weighting given to each particle when simulating the Ca radiance. Preliminary results suggest a high temperature ( I-2x 10(exp 4) K) source of atomic Ca concentrated over the dawn hemisphere. The high temperature is consistent with the dissociation of CaO in a near-surface exosphere with scale height <= 100 km, which imparts 2 eV to the freshly produced Ca atom. This source region and energy are consistent with data from the three MESSENGER flybys; whether this holds true for the data obtained in orbit is under investigation

    Early MESSENGER Results for Less Abundant or Weakly Emitting Species in Mercury's Exosphere

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    Now that the Messenger spacecraft is in orbit about Mercury, the extended observing time enables searches for exospheric species that are less abundant or weakly emitting compared with those for which emission has previously been detected. Many of these species cannot be observed from the ground because of terrestrial atmospheric absorption. We report here on the status of MESSENGER orbital-phase searches for additional species in Mercury's exosphere

    MESSENGER Searches for Less Abundant or Weakly Emitting Species in Mercury's Exosphere

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    Mercury's exosphere is composed of material that originates at the planet's surface, whether that material is native or delivered by the solar wind and micrometeoroids. Many exospheric species have been detected by remote sensing, including H and He by Mariner 10, Na, K, and Ca by ground-based observations, and H, Na, Ca, Mg, and Ca+ by the MErcury Surface, Space ENvironment, GEochemistry, and Ranging (MESSENGER) spacecraft. Other exospheric species, including Fe, AI, Si, 0, S, Mn, CI, Ti, OH, and their ions, are expected to be present on the basis of MESSENGER surface measurements and models of Mercury's surface chemistry. Here we report on searches for these species made with the Ultraviolet and Visible Spectrometer (UVVS) channel of the Mercury Atmospheric and Surface Composition Spectrometer (MASCS). No obvious signatures of the listed species have yet been observed in Mercury's exosphere by the UVVS as of this writing. It is possible that detections are elusive because the optimum regions of the exosphere have not been sampled. The Sun-avoidance constraints on MESSENGER place tight limits on instrument boresight directions, and some regions are probed infrequently. If there are strong spatial gradients in the distribution of weakly emitting species, a high-resolution sampling of specific regions may be required to detect them. Summing spectra over time will also aid in the ability to detect weaker emission. Observations to date nonetheless permit strong upper limits to be placed on the abundances of many undetected species, in some cases as functions of time and space. As those limits are lowered with time, the absence of detections can provide insight into surface composition and the potential source mechanisms of exospheric material

    Mercury's Exosphere During MESSENGER's Second Flyby: Detection of Magnesium and Distinct Distributions of Neutral Species

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    During MESSENGER's second Mercury flyby, the Mercury Atmospheric and Surface Composition Spectrometer observed emission from Mercury's neutral exosphere. These observations include the first detection of emission from magnesium. Differing spatial distributions for sodium, calcium, and magnesium were revealed by observations beginning in Mercury's tail region, approximately 8 Mercury radii anti-sunward of the planet, continuing past the nightside, and ending near the dawn terminator. Analysis of these observations, supplemented by observations during the first Mercury flyby as well as those by other MESSENGER instruments, suggests that the distinct spatial distributions arise from a combination of differences in source, transfer, and loss processes

    Mercury's Sodium Exosphere: Observations during the MESSENGER Orbital Phase

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    The MErcury Surface, Space ENvironment, GEochemistry, and Ranging (MESSENGER) spacecraft entered into orbit about Mercury on March 18,2011. We now have approximately five Mercury years of data from orbit. Prior to the MESSENGER mission, Mercury's surface-bounded exosphere was known to contain H, He, Na. K, and Ca. The Ultraviolet and Visible Spectrometer (UVVS) began routine orbital observations of both the dayside and nightside exosphere on March 29. 2011, measuring altitude profiles for all previously detected neutral species except for He and K. We focus here on what we have learned about the sodium exosphere: its spatial, seasonal, and sporadic variation. Observations to date permit delineation of the relative roles of photon-stimulated desorption (PSD) and impact vaporization (IV) from seasonal and spatial effects, as well as of the roles of ions both as sputtering agents and in their possible role to enhance the efficiency of PSD. Correlations of Mercury's neutral sodium exosphere with measurements from MESSENGER's Magnetometer (MAG) and Energetic Particle and Plasma Spectrometer (EPPS) provide insight into the roles of ions and electrons. Models incorporating MAG observations provide a basis for identifying the location and area of the surface exposed to solar wind plasma, and EPPS observations reveal episodic populations of energetic electrons in the magnetosphere and the presence of planetary He(+), 0(+), and Na(+)

    Mineralogy

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    The power of mineralogical analysis as a descriptive or predictive technique stems from the fact that only a few thousand minerals are known to occur in nature as compared to several hundred thousand inorganic compounds. Further, all of the known minerals have specific stability ranges in pressure, temperature, an composition. A specific knowledge of the mineralogy of a planets surface or interior therefore allows one to characterize the present or past conditions under which the minerals were formed or have existed. For the purposes of this paper, a slightly broader definition of mineralogy was adopted by including not only crystalline materials found on planetary surfaces, but also ices and classes that can benefit from in situ types of analyses. Both visual examination and the various spectroscopies available for robotic probes to planetary surfaces are discussed

    Mercury's Weather-Beaten Surface: Understanding Mercury in the Context of Lunar and Asteroid Space Weathering Studies

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    Understanding the composition of Mercury's crust is key to comprehending the formation of the planet. The regolith, derived from the crustal bedrock, has been altered via a set of space weathering processes. These processes are the same set of mechanisms that work to form Mercury's exosphere, and are moderated by the local space environment and the presence of an intrinsic planetary magnetic field. The alterations need to be understood in order to determine the initial crustal compositions. The complex interrelationships between Mercury's exospheric processes, the space environment, and surface composition are examined and reviewed. The processes are examined in the context of our understanding of these same processes on the lunar and asteroid regoliths. Keywords: Mercury (planet) Space weathering Surface processes Exosphere Surface composition Space environment
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