Dark Blue (dark + blue)

Distribution by Scientific Domains


Selected Abstracts


Influence of ambient light on the evolution of colour signals: comparative analysis of a Neotropical rainforest bird community

ECOLOGY LETTERS, Issue 4 2004
Doris Gomez
Abstract Rainforests offer two contrasted light environments: a bright canopy rich in blue and UV and a dark understorey, rich in green and orange. Therefore, natural selection for crypsis should favour dark brown signals in understorey and bright green signals in canopy, whereas sexual selection for conspicuousness should favour bright yellow-red signals in understorey and dark blue and UV signals in canopy. Using spectrometry and comparative analyses, we examined the relationship between ambient light and colour signals in a bird community of French Guiana. It appears that brightness and hue are mostly naturally selected, while UV content of plumage is more likely sexually selected. At each height, both sexes present similar coloration but males display more conspicuous sexually selected patterns than females. These results show that ambient light drives the evolution of colour signals at community scale, and should be considered when studying signalling in other communities and light-contrasted ecosystems. [source]


Localized ductile thrusting north of the Variscan Front, Ross Island, southwest Ireland

GEOLOGICAL JOURNAL, Issue 1 2003
Paul A. M. Nex
Abstract Two thrusts occur on Ross Island: the Head of Ross Thrust and the more southerly Ross Island Thrust. These lie to the north of the Killarney,Mallow Fault (KMF), the boundary frequently interpreted as the Variscan Front. The Ross Island Thrust, exposed in outcrop and in seven borehole cores, has emplaced dark blue,grey limestones of the Courceyan Ballysteen Formation over pale grey,brown Rockfield Limestone Formation of Chadian,Holkerian age. These lithologies at Ross Island exhibit a continuum of deformation at both the micro- and macro-scale, beginning with the generation of a spaced cleavage, formed during layer parallel shortening, that was subsequently rotated into parallelism with fold axial planes. Extensional microstructures are predominant in thin section and are associated with attenuation of the fold limb. Calcite veins are also attenuated and lie parallel to a mylonitic fabric close to the thrust plane. Lithological boundaries, the prominent pressure solution cleavage and the southerly dipping limb of an asymmetrical antiform are all parallel and form a composite planar anisotropy. This has controlled the location of the ductile Ross Island Thrust, which formed during the attenuation and shearing of a common fold limb. Ductile thrusts within the limestones at Ross Island contrast with the reactivation of basin-margin extensional faults further to the south along the major KMF. The Ross Island Thrust is considered to result from deformation ahead of the major northerly propagating Variscan décollement thrust and does not necessitate a continuous décollement structure north of the KMF. Mineralization at Ross Island exhibits remobilization associated with the formation of a pressure-solution cleavage and probably pre-dates thrusting. Copyright © 2003 John Wiley & Sons, Ltd. [source]


Electrochromic Polymer-Dispersed Liquid-Crystal Film: A New Bifunctional Device,

ADVANCED FUNCTIONAL MATERIALS, Issue 6 2005
P. Nicoletta
Abstract Polymer-dispersed liquid crystals (PDLCs) are liquid-crystal dispersions within a polymer matrix. These films can be changed from an opaque to a transparent state by applying a suitable alternating-current electric field. PDLCs have attracted the interest of researchers for their applications as light shutters, smart windows, and active displays. For such applications, electrochromic devices, which change color as a result of electrochemical reactions, have also become a recent focus of research. Herein, we report our preliminary results on bifunctional devices based on PDLCs that host electrochromic guest molecules. Such devices allow both an independent and fast switching from a scattering opaque state to a transmissive transparent state owing to liquid-crystal reorientation and a color change from white (pale yellow) to dark blue, due to either oxidation or reduction of the electrochromic molecules. [source]


Nanostructured Electrodes: The Role of Surface and Interface Energy on Phase Stability of Nanosized Insertion Compounds (Adv. Mater.

ADVANCED MATERIALS, Issue 25-26 2009
26/2009)
The cover shows three structures of the Li-ion battery electrode material LixFePO4 having two coexisting phases Li-rich: dark blue, Li-poor: light blue. The vertical decreasing dimension represents the downsizing of the particle size which leads to more similar Li-ion equilibrium concentrations in both phases, as indicated by the lower contrast between the blue shaded Li-ions. This result, reported by Marnix Wagemaker and co-workers on p. 2703, helps explain the changes in equilibrium properties in nanostructured insertion compounds such as Li-ion battery electrodes and H-storage materials. [source]


Cover Picture: Microscopic Evidence for Spatially Inhomogeneous Charge Trapping in Pentacene (Adv. Mater.

ADVANCED MATERIALS, Issue 11 2005
11/2005)
Abstract Trapped charge has been observed in polycrystalline pentacene films by electric force microscopy in work reported by Muller and Marohn on p.,1410. The cover shows an optical fiber watching the motion of a metal-coated cantilever hovering over a polycrystalline pentacene film. The film occupies the 6.5,,,m gap in a working field-effect transistor. Trapped charge (dark blue and black areas in the pentacene) appears as large patches randomly distributed throughout the device, implying that long-lived traps in polycrystalline pentacene are not correlated with grain boundaries. [source]


Persistent post-sclerotherapy pigmentation due to minocycline.

JOURNAL OF COSMETIC DERMATOLOGY, Issue 4 2002
Three cases, a review of post-sclerotherapy pigmentation
Summary, Background, Post-sclerotherapy pigmentation, usually overlying the treated veins and independent of any drug ingestion, is common. This pigmentation is brown and represents haemosiderin and sometimes melanin as well. It usually slowly fades over a period of months, only uncommonly persisting for years. Cutaneous pigmentation due to minocycline ingestion is a known but rare adverse effect. It usually appears as a round or irregular shaped patch that is dark blue to black, representing minocycline moieties and iron complexes. Its persistence for years is common. Clinically and histopathologically, these two causes of pigmentation are quite distinct. In the absence of ulceration, minocycline pigmentation koebnerised by sclerotherapy has not previously been reported. Aims, To determine the nature of the pigmentation appearing in three patients who had been taking minocycline at the time, or shortly after, they had received sclerotherapy. Clinically, although this pigmentation had the usual distribution observed after sclerotherapy, it was persistent and appeared dark blue to black. Results, The persistent post-sclerotherapy linear pigmentation observed in all three patients had the characteistics of minocycline pigmentation. Conclusions, This is the first report of such minocycline-aggravated post-sclerotherapy pigmentation. Persistent post-sclerotherapy pigmentation caused by minocycline is a risk associated with ingestion of this drug. Patients need to be warned of this risk because, unlike post-sclerotherapy pigmentation that develops in the absence of drug ingestion, minocycline-aggravated post-sclerotherapy pigmentation may persist for years. [source]


Highly Permeable Genipin-Cross-linked Gelatin Conduits Enhance Peripheral Nerve Regeneration

ARTIFICIAL ORGANS, Issue 12 2009
Ju-Ying Chang
Abstract Here we have evaluated peripheral nerve regeneration with a porous biodegradable nerve conduit (PGGC), which was made from genipin-cross-linked gelatin. To examine the effect of pores, nonporous genipin-cross-linked gelatin conduit (GGC) was considered as the control. Both the PGGC and the GGC were dark blue in appearance with a concentric and round lumina. The PGGC featured an outer surface with pores of variable size homogeneously traversing, and a partially fenestrated inner surface connected by an open trabecular meshwork. The GGC had a rough outer surface whereas its inner lumen was smooth. Both PGGCs and GGCs had similar hydrophilicity on condition of the same material and cross-linking degree. The porosity of PGGCs and GGCs was 90.8 ± 0.9% and 24.3 ± 2.9%, respectively. The maximum tensile force of the GGCs (0.12 ± 0.06 kN) exceeded that of the PGGCs (0.03 ± 0.01 kN), but the PGGCs had a higher swelling ratio than GGCs at 0.5, 1, 3, 6, 12, 24, 48, 60, 72, and 84 h after soaking in deionized water. Cytotoxic testing revealed the soaking solutions of both of the tube composites would not produce cytotoxicity to cocultured Schwann cells. After subcutaneous implantation on the dorsal side of the rat, the PGGC was degraded completely after 12 weeks of implantation whereas a thin tissue capsule was formed encapsulating the partially degraded GGC. Biodegradability of both of the tube groups and their effectiveness as a guidance channel were examined as they were used to repair a 10 mm gap in the rat sciatic nerve. As a result, fragmentation of the GGC was still seen after 12 weeks of implantation, yet the PGGC had been completely degraded. Histological observation showed that numerous myelinated axons had crossed over the gap region in the PGGCs after 8 weeks of implantation despite only few myelinated axons and unmyelinated axons mostly surrounded by Schwann cells seen in the GGCs. In addition, the regenerated nerves in the PGGCs presented a significantly higher nerve conductive velocity than those in the GGCs (P < 0.05). Thus, the PGGCs can not only offer effective aids for regenerating nerves but also accelerate favorable nerve functional recovery compared with the GGCs. [source]