The experience of power: Examining the effects of power on approach and inhibition tendencies.

Two studies of task-focused dyads tested the approach/inhibition theory of power (P. Keltner, D. H. Gruenfeld, & C. Anderson, in press), which posits that having power increases the tendency to approach and decreases the tendency to inhibit. Results provided preliminary support for the theory: Participants higher in personality dominance or assigned control over resources expressed their true attitudes, experienced more positive and less negative emotion, were more likely to perceive rewards (i.e., that their partner liked them), and were less likely to perceive threats (e.g., that their partner felt anger toward them). Most of these effects were mediated by the sense of power, suggesting that subjective feelings of power are an important component in the effects of power. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Equality of participation and influence in groups: The effects of communication medium and sex composition

We tested the claim that computer-mediated communication (CMC) is more egalitarian than face-to-face (FTF) communication by studying patterns of reported participation and influence in 30 FTF and 30 synchronous CMC groups over seven weeks. Twenty-two of these groups were composed of a majority of males or females; these were used to test effects of communication medium and sex composition on relative levels of participation and influence among group members. Competing predictions were derived from three theories: proportional theory, social role theory, and expectation states theory. Results indicated that CMC participation was perceived as more centralized than was FTF participation in groups' first meetings, but as similar for the remaining six meetings. Results revealed no or weak support for any of the competing theories of sex composition. Influence was perceived as most centralized in CMC majority-male groups and in FTF majority-female groups. In CMC groups, males in majority-female groups were perceived as having more influence than their female group members, whereas males in majority-male groups were perceived as having less influence than their female group members. In FTF groups, the ratio of male-to-female influence in majority-male and majority-female groups did not differ significantly. Implications of these findings and the need for additional longitudinal research are discussed.     

Time, technology and groups: An integration

This paper summarizes main findings of the five empirical papers in this issue, and discusses certain themes that connect them.     

The sexual harassment of uppity women.

In 3 studies, the author tested 2 competing views of sexual harassment: (a) It is motivated primarily by sexual desire and, therefore, is directed at women who meet feminine ideals, and (b) it is motivated primarily by a desire to punish gender-role deviants and, therefore, is directed at women who violate feminine ideals. Study 1 included male and female college students (N = 175) and showed that women with relatively masculine personalities (e.g., assertive, dominant, and independent) experienced the most sexual harassment. Study 2 (N = 134) showed that this effect was not because women with relatively masculine personalities were more likely than others to negatively evaluate potentially harassing scenarios. Study 3 included male and female employees at 5 organizations (N = 238) and showed that women in male-dominated organizations were harassed more than women in female-dominated organizations, and that women in male-dominated organizations who had relatively masculine personalities were sexually harassed the most. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Men, Women, and Leadership Centralization in Groups Over Time.

The authors propose a model for predicting the emergence of group norms from the demographic composition of groups. They use this model to study gender and leadership centralization in groups over time. Results from 2 longitudinal studies were consistent with their predictions: (a) Women, more than men, preferred equality norms in groups; (b) all-male and majority-male groups had relatively centralized leadership structures; (c) all-female groups had relatively decentralized leadership structures; and (d) balanced and majority-female groups were relatively centralized at the onset of group interaction but decreased in centralization over time. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Characteristics of infrared sky radiation in the United States

Extensive measurements of the thermal IR radiance of the sky were obtained at 6 U.S. locations: Tucson, AZ; San Antonio, TX; Gaithersburg, MD; St. Louis, MO; West Palm Beach, FL; and Boulder City, NV. Fifty thousand observations were obtained at half hour intervals during 1979 and 1980. Each observation consists of measurements in 7 spectral bands, wavelengths (in microns) of 8.1–13.7, 8.3–9.1, 9.4–9.9, 10.0–11.4, 14.0–15.8, 16.6–21.6 and 6–17 at zenith angles of 0, 20, 40, 60 and 80°. The data have been expressed and presented as apparent sky emissivities. It is shown that the measured spectral and angular sky emissivities can be reliably estimated from a knowledge of the total (global) sky emissivity, using an empirical “sky emissivity” equation. The results are of particular relevance to the performance of radiative cooling systems designed to make use of spectral and/or angular selectivity.     

Methods of creating solar-reflective nonwhite surfaces and their application to residential roofing materials

We describe methods for creating solar-reflective nonwhite surfaces and their application to a wide variety of residential roofing materials, including metal, clay tile, concrete tile, wood, and asphalt shingle. Reflectance in the near-infrared (NIR) spectrum (0.7–2.5 μm) is maximized by coloring a topcoat with pigments that weakly absorb and (optionally) strongly backscatter NIR radiation, and by adding an NIR-reflective basecoat (e.g., one colored with titanium dioxide rutile white) if both the topcoat and the substrate weakly reflect NIR radiation. Coated steel and glazed clay-tile roofing products achieved NIR reflectances of up to 0.50 and 0.75, respectively, using only cool topcoats. Gray-cement concrete tiles achieved NIR reflectances as high as 0.60 with coatings colored by NIR-scattering pigments. Such tiles could attain NIR reflectances of up to 0.85 by overlaying a white basecoat with a topcoat colored by NIR-transparent organic pigments. Granule-surfaced asphalt shingles achieved NIR reflectances as high as 0.45 when the granules were covered with a white basecoat and a cool color topcoat.     

Solar spectral optical properties of pigments—Part II: survey of common colorants

Various pigments are characterized by determination of parameters S (backscattering) and K (absorption) as functions of wavelength in the solar spectral range of 300–2500 nm. Measured values of S for generic titanium dioxide (rutile) white pigment are in rough agreement with values computed from the Mie theory, supplemented by a simple multiple scattering model. Pigments in widespread use are examined, with particular emphasis on those that may be useful for formulating non-white materials that can reflect the near-infrared (NIR) portion of sunlight, such as the complex inorganic color pigments (mixed metal oxides). These materials remain cooler in sunlight than comparable NIR-absorbing colors. NIR-absorptive pigments are to be avoided. High NIR reflectance can be produced by a reflective metal substrate, an NIR-reflective underlayer, and/or by the use of a pigment that scatters strongly in the NIR.     

Chemical and microbial effects of atmospheric particles on the performance of steep-slope roofing materials

The reflectivity of a roof is a critical component in design of strategy to reduce overall building energy usage. Airborne particulate matter that settles on a roof can either reflect or absorb incoming solar radiation. The light scattering and absorption processes occur within a few microns of the surface that affects the solar reflectance of the roof. The long-term loss of roof reflectivity appears driven by the ability of the atmospheric particulate matter to cling onto the roof and resist being washed off by wind and or rain. Contaminants collected from samples of roof products exposed at seven California sites for about one and a half years were analysed for major and trace elements and carbons to assist characterization of the chemical profile of the atmospheric particles that soil each roof sample. The chemical composition of the accumulated particles was very similar across the state of California; there was no clear distinction from one region to another. Elemental carbon did not contribute significantly to the loss of solar reflectance as initially expected. Dust particles and organic carbon compensated for the loss of solar reflectance due to elemental carbon possibly because some crystalline forms of these elements were light reflecting and contributed to the solar reflectance. Differences in microbial communities and biomass were seen between the various materials. Abundance of microbial biomass on roof tiles appears to be related to the composition/surface structure of the tile. Cyanobacteria or fungi represent the dominant player.     

Measuring solar reflectance—Part II: Review of practical methods

A companion article explored how solar reflectance varies with surface orientation and solar position, and found that clear sky air mass 1 global horizontal (AM1GH) solar reflectance is a preferred quantity for estimating solar heat gain. In this study we show that AM1GH solar reflectance R_g,0 can be accurately measured with a pyranometer, a solar spectrophotometer, or an updated edition of the Solar Spectrum Reflectometer (version 6). Of primary concern are errors that result from variations in the spectral and angular distributions of incident sunlight.Neglecting shadow, background and instrument errors, the conventional pyranometer technique can measure R_g,0 to within 0.01 for surface slopes up to 5:12 [23°], and to within 0.02 for surface slopes up to 12:12 [45°]. An alternative pyranometer method minimizes shadow errors and can be used to measure R_g,0 of a surface as small as 1 m in diameter. The accuracy with which it can measure R_g,0 is otherwise comparable to that of the conventional pyranometer technique.A solar spectrophotometer can be used to determine , a solar reflectance computed by averaging solar spectral reflectance weighted with AM1GH solar spectral irradiance. Neglecting instrument errors, matches R_g,0 to within 0.006. The air mass 1.5 solar reflectance measured with version 5 of the Solar Spectrum Reflectometer can differ from by as much as 0.08, but the AM1GH output of version 6 of this instrument matches to within about 0.01.