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Ian D. Stephen Miriam J. Law Smith Michael R. Stirrat David I. Perrett 《International journal of primatology》2009,30(6):845-857
Numerous researchers have examined the effects of skin condition, including texture and color, on the perception of health,
age, and attractiveness in human faces. They have focused on facial color distribution, homogeneity of pigmentation, or skin
quality. We here investigate the role of overall skin color in determining perceptions of health from faces by allowing participants
to manipulate the skin portions of color-calibrated Caucasian face photographs along CIELab color axes. To enhance healthy
appearance, participants increased skin redness (a*), providing additional support for previous findings that skin blood color enhances the healthy appearance of faces. Participants
also increased skin yellowness (b*) and lightness (L*), suggesting a role for high carotenoid and low melanin coloration in the healthy appearance of faces. The color preferences
described here resemble the red and yellow color cues to health displayed by many species of nonhuman animals. 相似文献
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Ann Trevallion R. Johnston D.M. Finlayson N.T. Nicoll 《Journal of experimental marine biology and ecology》1973,11(2):189-206
Tellina tennis Da Costa was kept for four months in four large outdoor tanks containing sand and sea water. There was a 10 % daily exchange of sea water, pumped directly from the sea. Three tanks received daily addition of nutrients in the form of sodium nitrate and sodium dihydrogen phosphate, giving enrichment of approximately 3, 10, and 30 times natural sea-water levels of nitrate in the different tanks. Phosphate, nitrate, chlorophyll, and organic carbon in the water were measured regularly, the nitrate by Autoanalyser. Water temperature and solar radiation were recorded. Zooplankton samples were taken daily and Tellina were sampled monthly for length, weight, and biochemical analysis of tissues.Phosphate was always present in excess. The lowest level of nitrogen enrichment resulted in almost complete utilisation of nitrate, with a significant increase of organic carbon and chlorophyll above control levels. Zooplankton occurred in the greatest numbers in this tank, and Tellina showed the best survival, growth, and condition. In the tanks with the higher levels of enrichment, excess nutrients led to growth of macrophytic algae on the surface and sides of tank. This had an adverse effect on the phytoplankton production: zooplankton numbers were lower, as was growth of Tellina. 相似文献
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The black mutant larva of Manduca sexta contains approximately the same quantity of carotenoids as the normal green type, but there is possibly a slight qualitative difference between them, the former storing more β-carotene and less violaxanthin. 相似文献
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Nakita K. Noel Severin N. Habisreutinger Bernard Wenger Yen‐Hung Lin Fengyu Zhang Jay B. Patel Antoine Kahn Michael B. Johnston Henry J. Snaith 《Liver Transplantation》2020,10(4)
Halide perovskites are currently one of the most heavily researched emerging photovoltaic materials. Despite achieving remarkable power conversion efficiencies, perovskite solar cells have not yet achieved their full potential, with the interfaces between the perovskite and the charge‐selective layers being where most recombination losses occur. In this study, a fluorinated ionic liquid (IL) is employed to modify the perovskite/SnO2 interface. Using Kelvin probe and photoelectron spectroscopy measurements, it is shown that depositing the perovskite onto an IL‐treated substrate results in the crystallization of a perovskite film which has a more n‐type character, evidenced by a decrease of the work function and a shift of the Fermi level toward the conduction band. Photoluminescence spectroscopy and time‐resolved microwave conductivity are used to investigate the optoelectronic properties of the perovskite grown on neat and IL‐modified surfaces and it is found that the modified substrate yields a perovskite film which exhibits an order of magnitude lower trap density than the control. When incorporated into solar cells, this interface modification results in a reduction in the current–voltage hysteresis and an improvement in device performance, with the best performing devices achieving steady‐state PCEs exceeding 20%. 相似文献
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Sociality has evolved independently many times in a diverse array of animal taxa. While sociality in some invertebrates, birds and mammals is relatively well understood, complex social behaviour in Squamate reptiles is a comparatively recent discovery. The extent to which social behaviour is phylogenetically constrained, or free to respond to environmental conditions is a key question in understanding sociality. We sampled 74 aggregations involving 137 individuals of a social lizard (Egernia stokesii) from 13 sites across a 96 250 km2 area showing a wide range of environmental conditions. Over all locations, 70% of the lizards were found in aggregations, supporting the previous suggestion that aggregation in this species is phylogenetically constrained. However, the size of aggregations was negatively related to spatial variation in aridity and daily variation in maximum temperature, suggesting that social behaviour also varied in response to harsh environmental conditions. Lizards aggregated more in arid areas and on cold days. Our results show that it is overly simplistic to regard social behaviour in E. stokesii as either phylogenetically constrained or environmentally determined. A more nuanced appreciation of the extent to which social behaviour is free to vary in response to environmental conditions improves our understanding of social behaviour in Squamate reptiles. 相似文献