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Sample records for wing color pattern

  1. Stable structural color patterns displayed on transparent insect wings.

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    Shevtsova, Ekaterina; Hansson, Christer; Janzen, Daniel H; Kjærandsen, Jostein

    2011-01-11

    Color patterns play central roles in the behavior of insects, and are important traits for taxonomic studies. Here we report striking and stable structural color patterns--wing interference patterns (WIPs)--in the transparent wings of small Hymenoptera and Diptera, patterns that have been largely overlooked by biologists. These extremely thin wings reflect vivid color patterns caused by thin film interference. The visibility of these patterns is affected by the way the insects display their wings against various backgrounds with different light properties. The specific color sequence displayed lacks pure red and matches the color vision of most insects, strongly suggesting that the biological significance of WIPs lies in visual signaling. Taxon-specific color patterns are formed by uneven membrane thickness, pigmentation, venation, and hair placement. The optically refracted pattern is also stabilized by microstructures of the wing such as membrane corrugations and spherical cell structures that reinforce the pattern and make it essentially noniridescent over a large range of light incidences. WIPs can be applied to map the micromorphology of wings through direct observation and are useful in several fields of biology. We demonstrate their usefulness as identification patterns to solve cases of cryptic species complexes in tiny parasitic wasps, and indicate their potentials for research on the genetic control of wing development through direct links between the transregulatory wing landscape and interference patterns we observe in Drosophila model species. Some species display sexually dimorphic WIPs, suggesting sexual selection as one of the driving forces for their evolution.

  2. Color pattern analysis of nymphalid butterfly wings: revision of the nymphalid groundplan.

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    Otaki, Joji M

    2012-09-01

    To better understand the developmental mechanisms of color pattern variation in butterfly wings, it is important to construct an accurate representation of pattern elements, known as the "nymphalid groundplan". However, some aspects of the current groundplan remain elusive. Here, I examined wing-wide elemental patterns of various nymphalid butterflies and confirmed that wing-wide color patterns are composed of the border, central, and basal symmetry systems. The central and basal symmetry systems can express circular patterns resembling eyespots, indicating that these systems have developmental mechanisms similar to those of the border symmetry system. The wing root band commonly occurs as a distinct symmetry system independent from the basal symmetry system. In addition, the marginal and submarginal bands are likely generated as a single system, referred to as the "marginal band system". Background spaces between two symmetry systems are sometimes light in coloration and can produce white bands, contributing significantly to color pattern diversity. When an element is enlarged with a pale central area, a visually similar (yet developmentally distinct) white band is produced. Based on the symmetric relationships of elements, I propose that both the central and border symmetry systems are comprised of "core elements" (the discal spot and the border ocelli, respectively) and a pair of "paracore elements" (the distal and proximal bands and the parafocal elements, respectively). Both core and paracore elements can be doubled, or outlined. Developmentally, this system configuration is consistent with the induction model, but not with the concentration gradient model for positional information.

  3. Cryptically patterned moths perceive bark structure when choosing body orientations that match wing color pattern to the bark pattern.

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    Chang-Ku Kang

    Full Text Available Many moths have wing patterns that resemble bark of trees on which they rest. The wing patterns help moths to become camouflaged and to avoid predation because the moths are able to assume specific body orientations that produce a very good match between the pattern on the bark and the pattern on the wings. Furthermore, after landing on a bark moths are able to perceive stimuli that correlate with their crypticity and are able to re-position their bodies to new more cryptic locations and body orientations. However, the proximate mechanisms, i.e. how a moth finds an appropriate resting position and orientation, are poorly studied. Here, we used a geometrid moth Jankowskia fuscaria to examine i whether a choice of resting orientation by moths depends on the properties of natural background, and ii what sensory cues moths use. We studied moths' behavior on natural (a tree log and artificial backgrounds, each of which was designed to mimic one of the hypothetical cues that moths may perceive on a tree trunk (visual pattern, directional furrow structure, and curvature. We found that moths mainly used structural cues from the background when choosing their resting position and orientation. Our findings highlight the possibility that moths use information from one type of sensory modality (structure of furrows is probably detected through tactile channel to achieve crypticity in another sensory modality (visual. This study extends our knowledge of how behavior, sensory systems and morphology of animals interact to produce crypsis.

  4. Sexual selection on wing interference patterns in Drosophila melanogaster.

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    Katayama, Natsu; Abbott, Jessica K; Kjærandsen, Jostein; Takahashi, Yuma; Svensson, Erik I

    2014-10-21

    Animals with color vision use color information in intra- and interspecific communication, which in turn may drive the evolution of conspicuous colored body traits via natural and sexual selection. A recent study found that the transparent wings of small flies and wasps in lower-reflectance light environments display vivid and stable structural color patterns, called "wing interference patterns" (WIPs). Such WIPs were hypothesized to function in sexual selection among small insects with wing displays, but this has not been experimentally verified. Here, to our knowledge we present the first experimental evidence that WIPs in males of Drosophila melanogaster are targets of mate choice from females, and that two different color traits--saturation and hue--experience directional and stabilizing sexual selection, respectively. Using isogenic lines from the D. melanogaster Genetic Reference Panel, we compare attractiveness of different male WIPs against black and white visual backgrounds. We show that males with more vivid wings are more attractive to females than are males with dull wings. Wings with a large magenta area (i.e., intermediate trait values) were also preferred over those with a large blue or yellow area. These experimental results add a visual element to the Drosophila mating array, integrating sexual selection with elements of genetics and evo-devo, potentially applicable to a wide array of small insects with hyaline wings. Our results further underscore that the mode of sexual selection on such visual signals can differ profoundly between different color components, in this case hue and saturation.

  5. Structural colors from Morpho peleides butterfly wing scales

    KAUST Repository

    Ding, Yong

    2009-01-01

    A male Morpho peleides butterfly wing is decorated by two types of scales, cover and ground scales. We have studied the optical properties of each type of scales in conjunction with the structural information provided by cross-sectional transmission electron microscopy and computer simulation. The shining blue color is mainly from the Bragg reflection of the one-dimensional photonic structure, e.g., the shelf structure packed regularly in each ridges on cover scales. A thin-film-like interference effect from the base plate of the cover scale enhances such blue color and further gives extra reflection peaks in the infrared and ultraviolet regions. The analogy in the spectra acquired from the original wing and that from the cover scales suggests that the cover scales take a dominant role in its structural color. This study provides insight of using the biotemplates for fabricating smart photonic structures. © 2009 American Institute of Physics.

  6. Spectrally tuned structural and pigmentary coloration of birdwing butterfly wing scales

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    Wilts, Bodo D.; Matsushita, Atsuko; Arikawa, Kentaro; Stavenga, Doekele G.

    2015-01-01

    The colourful wing patterns of butterflies play an important role for enhancing fitness; for instance, by providing camouflage, for interspecific mate recognition, or for aposematic display. Closely related butterfly species can have dramatically different wing patterns. The phenomenon is assumed to be caused by ecological processes with changing conditions, e.g. in the environment, and also by sexual selection. Here, we investigate the birdwing butterflies, Ornithoptera, the largest butterflies of the world, together forming a small genus in the butterfly family Papilionidae. The wings of these butterflies are marked by strongly coloured patches. The colours are caused by specially structured wing scales, which act as a chirped multilayer reflector, but the scales also contain papiliochrome pigments, which act as a spectral filter. The combined structural and pigmentary effects tune the coloration of the wing scales. The tuned colours are presumably important for mate recognition and signalling. By applying electron microscopy, (micro-)spectrophotometry and scatterometry we found that the various mechanisms of scale coloration of the different birdwing species strongly correlate with the taxonomical distribution of Ornithoptera species. PMID:26446560

  7. Butterfly wing colors : glass scales of Graphium sarpedon cause polarized iridescence and enhance blue/green pigment coloration of the wing membrane

    NARCIS (Netherlands)

    Stavenga, Doekele G.; Giraldo, Marco A.; Leertouwer, Hein L.

    2010-01-01

    The wings of the swordtail butterfly Graphium sarpedon nipponum contain the bile pigment sarpedobilin, which causes blue/green colored wing patches. Locally the bile pigment is combined with the strongly blue-absorbing carotenoid lutein, resulting in green wing patches and thus improving camouflage.

  8. Comparative insights into questions of lepidopteran wing pattern homology

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    Stockslager Steven

    2006-11-01

    Full Text Available Abstract Background Butterfly and moth eyespots can share a similar appearance, involving multiple concentric rings of colored scales, but usually occuring in non-homologous positions on the wing. Within the butterflies, on the other hand, spots that share the same homologous position may not share the concentric ring structure; and, in butterfly species that have eyespots with concentric rings, ectopic eyespots with a similar ring structure can be induced by means of a simple epidermal wound. The extent to which all these eyespots, natural or induced, share similar genes and developmental mechanisms is investigated here by means of protein in-situ localizations in selected butterfly and moth species. In addition to looking at some of the transcription factors previously identified as being involved in eyespot formation, we also tested the involvement of candidate genes from the Wingless and TGF-β signaling pathways as putative morphogens for eyespot development. Results Saturniid moth and nymphalid butterfly eyespots with concentric rings of color express at least two transcription factors, Distal-less and Engrailed, in the center of the future pattern. Nymphalid eyespots centers also express the ligand Wingless and an activated signal transducer, a phosphorylated Smad protein, but neither these proteins nor the previous two proteins are found in pierid spot centers, which consist of a single patch of color. Both butterfly wing patterns, however, express a third transcription factor, Spalt, a portion of whose expression domain maps to the black scales on the adult wing. Wounding a nymphalid wing, on the other hand, leads to upregulation of Distal-less, engrailed and spalt in subsets of cells around the wounding site, mimicking concentric eyespot development. Conclusion Wingless and TGF-β ligands are both candidate morphogens involved in nymphalid butterfly eyespot formation. These eyespots, as well as saturniid moth eyespots with concentric

  9. Detailed electromagnetic simulation for the structural color of butterfly wings.

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    Lee, R Todd; Smith, Glenn S

    2009-07-20

    Many species of butterflies exhibit interesting optical phenomena due to structural color. The physical reason for this color is subwavelength features on the surface of a single scale. The exposed surface of a scale is covered with a ridge structure. The fully three-dimensional, periodic, finite-difference time-domain method is used to create a detailed electromagnetic model of a generic ridge. A novel method for presenting the three-dimensional observed color pattern is developed. Using these tools, the change in color that is a result of varying individual features of the scale is explored. Computational models are developed that are similar to three butterflies: Morpho rhetenor, Troides magellanus, and Ancyluris meliboeus.

  10. Wnt signaling underlies evolution and development of the butterfly wing pattern symmetry systems.

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    Martin, Arnaud; Reed, Robert D

    2014-11-15

    Most butterfly wing patterns are proposed to be derived from a set of conserved pattern elements known as symmetry systems. Symmetry systems are so-named because they are often associated with parallel color stripes mirrored around linear organizing centers that run between the anterior and posterior wing margins. Even though the symmetry systems are the most prominent and diverse wing pattern elements, their study has been confounded by a lack of knowledge regarding the molecular basis of their development, as well as the difficulty of drawing pattern homologies across species with highly derived wing patterns. Here we present the first molecular characterization of symmetry system development by showing that WntA expression is consistently associated with the major basal, discal, central, and external symmetry system patterns of nymphalid butterflies. Pharmacological manipulations of signaling gradients using heparin and dextran sulfate showed that pattern organizing centers correspond precisely with WntA, wingless, Wnt6, and Wnt10 expression patterns, thus suggesting a role for Wnt signaling in color pattern induction. Importantly, this model is supported by recent genetic and population genomic work identifying WntA as the causative locus underlying wing pattern variation within several butterfly species. By comparing the expression of WntA between nymphalid butterflies representing a range of prototypical symmetry systems, slightly deviated symmetry systems, and highly derived wing patterns, we were able to infer symmetry system homologies in several challenging cases. Our work illustrates how highly divergent morphologies can be derived from modifications to a common ground plan across both micro- and macro-evolutionary time scales. Copyright © 2014 Elsevier Inc. All rights reserved.

  11. The redder the better: wing color predicts flight performance in monarch butterflies.

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    Andrew K Davis

    Full Text Available The distinctive orange and black wings of monarchs (Danaus plexippus have long been known to advertise their bitter taste and toxicity to potential predators. Recent work also showed that both the orange and black coloration of this species can vary in response to individual-level and environmental factors. Here we examine the relationship between wing color and flight performance in captive-reared monarchs using a tethered flight mill apparatus to quantify butterfly flight speed, duration and distance. In three different experiments (totaling 121 individuals we used image analysis to measure body size and four wing traits among newly-emerged butterflies prior to flight trials: wing area, aspect ratio (length/width, melanism, and orange hue. Results showed that monarchs with darker orange (approaching red wings flew longer distances than those with lighter orange wings in analyses that controlled for sex and other morphometric traits. This finding is consistent with past work showing that among wild monarchs, those sampled during the fall migration are darker in hue (redder than non-migratory monarchs. Together, these results suggest that pigment deposition onto wing scales during metamorphosis could be linked with traits that influence flight, such as thorax muscle size, energy storage or metabolism. Our results reinforce an association between wing color and flight performance in insects that is suggested by past studies of wing melansim and seasonal polyphenism, and provide an important starting point for work focused on mechanistic links between insect movement and color.

  12. The redder the better: wing color predicts flight performance in monarch butterflies.

    Science.gov (United States)

    Davis, Andrew K; Chi, Jean; Bradley, Catherine; Altizer, Sonia

    2012-01-01

    The distinctive orange and black wings of monarchs (Danaus plexippus) have long been known to advertise their bitter taste and toxicity to potential predators. Recent work also showed that both the orange and black coloration of this species can vary in response to individual-level and environmental factors. Here we examine the relationship between wing color and flight performance in captive-reared monarchs using a tethered flight mill apparatus to quantify butterfly flight speed, duration and distance. In three different experiments (totaling 121 individuals) we used image analysis to measure body size and four wing traits among newly-emerged butterflies prior to flight trials: wing area, aspect ratio (length/width), melanism, and orange hue. Results showed that monarchs with darker orange (approaching red) wings flew longer distances than those with lighter orange wings in analyses that controlled for sex and other morphometric traits. This finding is consistent with past work showing that among wild monarchs, those sampled during the fall migration are darker in hue (redder) than non-migratory monarchs. Together, these results suggest that pigment deposition onto wing scales during metamorphosis could be linked with traits that influence flight, such as thorax muscle size, energy storage or metabolism. Our results reinforce an association between wing color and flight performance in insects that is suggested by past studies of wing melansim and seasonal polyphenism, and provide an important starting point for work focused on mechanistic links between insect movement and color.

  13. The Redder the Better: Wing Color Predicts Flight Performance in Monarch Butterflies

    Science.gov (United States)

    Davis, Andrew K.; Chi, Jean; Bradley, Catherine; Altizer, Sonia

    2012-01-01

    The distinctive orange and black wings of monarchs (Danaus plexippus) have long been known to advertise their bitter taste and toxicity to potential predators. Recent work also showed that both the orange and black coloration of this species can vary in response to individual-level and environmental factors. Here we examine the relationship between wing color and flight performance in captive-reared monarchs using a tethered flight mill apparatus to quantify butterfly flight speed, duration and distance. In three different experiments (totaling 121 individuals) we used image analysis to measure body size and four wing traits among newly-emerged butterflies prior to flight trials: wing area, aspect ratio (length/width), melanism, and orange hue. Results showed that monarchs with darker orange (approaching red) wings flew longer distances than those with lighter orange wings in analyses that controlled for sex and other morphometric traits. This finding is consistent with past work showing that among wild monarchs, those sampled during the fall migration are darker in hue (redder) than non-migratory monarchs. Together, these results suggest that pigment deposition onto wing scales during metamorphosis could be linked with traits that influence flight, such as thorax muscle size, energy storage or metabolism. Our results reinforce an association between wing color and flight performance in insects that is suggested by past studies of wing melansim and seasonal polyphenism, and provide an important starting point for work focused on mechanistic links between insect movement and color. PMID:22848463

  14. Coloration principles of nymphaline butterflies - thin films, melanin, ommochromes and wing scale stacking.

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    Stavenga, Doekele G; Leertouwer, Hein L; Wilts, Bodo D

    2014-06-15

    The coloration of the common butterflies Aglais urticae (small tortoiseshell), Aglais io (peacock) and Vanessa atalanta (red admiral), belonging to the butterfly subfamily Nymphalinae, is due to the species-specific patterning of differently coloured scales on their wings. We investigated the scales' structural and pigmentary properties by applying scanning electron microscopy, (micro)spectrophotometry and imaging scatterometry. The anatomy of the wing scales appears to be basically identical, with an approximately flat lower lamina connected by trabeculae to a highly structured upper lamina, which consists of an array of longitudinal, parallel ridges and transversal crossribs. Isolated scales observed at the abwing (upper) side are blue, yellow, orange, red, brown or black, depending on their pigmentation. The yellow, orange and red scales contain various amounts of 3-OH-kynurenine and ommochrome pigment, black scales contain a high density of melanin, and blue scales have a minor amount of melanin pigment. Observing the scales from their adwing (lower) side always revealed a structural colour, which is blue in the case of blue, red and black scales, but orange for orange scales. The structural colours are created by the lower lamina, which acts as an optical thin film. Its reflectance spectrum, crucially determined by the lamina thickness, appears to be well tuned to the scales' pigmentary spectrum. The colours observed locally on the wing are also due to the degree of scale stacking. Thin films, tuned pigments and combinations of stacked scales together determine the wing coloration of nymphaline butterflies. © 2014. Published by The Company of Biologists Ltd.

  15. Nanofabrication and coloration study of artificial Morpho butterfly wings with aligned lamellae layers

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    Zhang, Sichao; Chen, Yifang

    2015-01-01

    The bright and iridescent blue color from Morpho butterfly wings has attracted worldwide attentions to explore its mysterious nature for long time. Although the physics of structural color by the nanophotonic structures built on the wing scales has been well established, replications of the wing structure by standard top-down lithography still remains a challenge. This paper reports a technical breakthrough to mimic the blue color of Morpho butterfly wings, by developing a novel nanofabrication process, based on electron beam lithography combined with alternate PMMA/LOR development/dissolution, for photonic structures with aligned lamellae multilayers in colorless polymers. The relationship between the coloration and geometric dimensions as well as shapes is systematically analyzed by solving Maxwell’s Equations with a finite domain time difference simulator. Careful characterization of the mimicked blue by spectral measurements under both normal and oblique angles are carried out. Structural color in blue reflected by the fabricated wing scales, is demonstrated and further extended to green as an application exercise of the new technique. The effects of the regularity in the replicas on coloration are analyzed. In principle, this approach establishes a starting point for mimicking structural colors beyond the blue in Morpho butterfly wings. PMID:26577813

  16. Human Preferences for Colorful Birds: Vivid Colors or Pattern?

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    Silvie Lišková

    2015-04-01

    Full Text Available In a previous study, we found that the shape of a bird, rather than its color, plays a major role in the determination of human preferences. Thus, in the present study, we asked whether the preferences of human respondents towards uniformly shaped, colorful birds are determined by pattern rather than color. The experimental stimuli were pictures of small passerine birds of the family Pittidae possessing uniform shape but vivid coloration. We asked 200 participants to rank 43 colored and 43 identical, but grayscaled, pictures of birds. To find the traits determining human preferences, we performed GLM analysis in which we tried to explain the mean preference ranks and PC axes by the following explanatory variables: the overall lightness and saturation, edges (pattern, and the portion of each of the basic color hues. The results showed that the mean preference ranks of the grayscale set is explained mostly by the birds' pattern, whereas the colored set ranking is mostly determined by the overall lightness. The effect of colors was weaker, but still significant, and revealed that people liked blue and green birds. We found no significant role of the color red, the perception of which was acquired relatively recently in evolution.

  17. Human preferences for colorful birds: Vivid colors or pattern?

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    Lišková, Silvie; Landová, Eva; Frynta, Daniel

    2015-04-29

    In a previous study, we found that the shape of a bird, rather than its color, plays a major role in the determination of human preferences. Thus, in the present study, we asked whether the preferences of human respondents towards uniformly shaped, colorful birds are determined by pattern rather than color. The experimental stimuli were pictures of small passerine birds of the family Pittidae possessing uniform shape but vivid coloration. We asked 200 participants to rank 43 colored and 43 identical, but grayscaled, pictures of birds. To find the traits determining human preferences, we performed GLM analysis in which we tried to explain the mean preference ranks and PC axes by the following explanatory variables: the overall lightness and saturation, edges (pattern), and the portion of each of the basic color hues. The results showed that the mean preference ranks of the grayscale set is explained mostly by the birds' pattern, whereas the colored set ranking is mostly determined by the overall lightness. The effect of colors was weaker, but still significant, and revealed that people liked blue and green birds. We found no significant role of the color red, the perception of which was acquired relatively recently in evolution.

  18. Giving eyespots a shiner: Pharmacologic manipulation of the Io moth wing pattern.

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    Sourakov, Andrei

    2017-01-01

    Our knowledge of wing pattern formation in Lepidoptera has advanced significantly in recent years due to the careful examination of several groups of butterflies. The eyespot is a prominent feature of Lepidoptera wing pattern, especially in the family Saturniidae. The present study examined how sulfated polysaccharides affected the wing pattern formation of the Io moth, Automeris io (Saturniidae).  Prepupae and pupae of this species were subjected to injections of heparin and cold shock. While the cold shock had little to no effect on wing pattern, the aberrations resulting from heparin injections were moderate to profound and depended on the dose and the stage at which injection was made. The changes consisted of expansion of the black ring around the dorsal hindwing eyespots and distortion of discal spots on both dorsal and ventral sides of forewings, suggesting a possible link between genetic controls of these elements. Several different types of scales form the normal color pattern of Automeris io , and heparin-induced changes correspond to changes in shape of scales. The resulting aberrations are dubbed 'Black Eye' and 'Comet Eye.' Other known aberrations of Automeris io eyespots are summarized, illustrated, and named.

  19. Color pattern evolution in Vanessa butterflies (Nymphalidae: Nymphalini): non-eyespot characters.

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    Abbasi, Roohollah; Marcus, Jeffrey M

    2015-01-01

    A phylogenetic approach was used to study color pattern evolution in Vanessa butterflies. Twenty-four color pattern elements from the Nymphalid ground plan were identified on the dorsal and ventral surfaces of the fore- and hind wings. Eyespot characters were excluded and will be examined elsewhere. The evolution of each character was traced over a Bayesian phylogeny of Vanessa reconstructed from 7750 DNA base pairs from 10 genes. Generally, the correspondence between character states on the same surface of the two wings is stronger on the ventral side compared to the dorsal side. The evolution of character states on both sides of a wing correspond with each other in most extant species, but the correspondence between dorsal and ventral character states is much stronger in the forewing than in the hindwing. The dorsal hindwing of many species of Vanessa is covered with an extended Basal Symmetry System and the Discalis I pattern element is highly variable between species, making this wing surface dissimilar to the other wing surfaces. The Basal Symmetry System and Discalis I may contribute to behavioral thermoregulation in Vanessa. Overall, interspecific directional character state evolution of non-eyespot color patterns is relatively rare in Vanessa, with a majority of color pattern elements showing non-variable, non-directional, or ambiguous character state evolution. The ease with which the development of color patterns can be modified, including character state reversals, has likely made important contributions to the production of color pattern diversity in Vanessa and other butterfly groups. © 2014 Wiley Periodicals, Inc.

  20. Thermal impact of migrating birds' wing color on their flight performance: Possibility of new generation of biologically inspired drones.

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    Hassanalian, M; Abdelmoula, H; Ben Ayed, S; Abdelkefi, A

    2017-05-01

    The thermal impact of the birds' color on their flight performance are investigated. In most of the large migrating birds, the top of their wings is black. Considering this natural phenomenon in the migrating birds, such as albatross, a thermal analysis of the boundary layer of their wings is performed during the year depending on the solar insulation. It is shown that the temperature difference between the bright and dark colored top wing surface is around 10°C. The dark color on the top of the wing increases the temperature of the boundary layer over the wing which consequently reduces the skin drag force over the wing. This reduction in the drag force can be considered as one of the effective factors for long endurance of these migrating birds. This research should lead to improved designs of the drones by applying the inspired colors which can help drones increase their endurance. Copyright © 2017 Elsevier Ltd. All rights reserved.

  1. Does skipping a meal matter to a butterfly's appearance? Effects of larval food stress on wing morphology and color in monarch butterflies.

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    Haley Johnson

    Full Text Available In animals with complex life cycles, all resources needed to form adult tissues are procured at the larval stage. For butterflies, the proper development of wings involves synthesizing tissue during metamorphosis based on the raw materials obtained by larvae. Similarly, manufacture of pigment for wing scales also requires resources acquired by larvae. We conducted an experiment to test the effects of food deprivation in the larval stage on multiple measures of adult wing morphology and coloration of monarch butterflies (Danaus plexippus, a species in which long-distance migration makes flight efficiency critical. In a captive setting, we restricted food (milkweed from late-stage larvae for either 24 hrs or 48 hrs, then after metamorphosis we used image analysis methods to measure forewing surface area and elongation (length/width, which are both important for migration. We also measured the brightness of orange pigment and the intensity of black on the wing. There were correlations between several wing features, including an unexpected association between wing elongation and melanism, which will require further study to fully understand. The clearest effect of food restriction was a reduction in adult wing size in the high stress group (by approximately 2%. Patterns observed for other wing traits were ambiguous: monarchs in the low stress group (but not the high had less elongated and paler orange pigmentation. There was no effect on wing melanism. Although some patterns obtained in this study were unclear, our results concerning wing size have direct bearing on the monarch migration. We show that if milkweed is limited for monarch larvae, their wings become stunted, which could ultimately result in lower migration success.

  2. Role of wing color and seasonal changes in ambient temperature and solar irradiation on predicted flight efficiency of the Albatross.

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    Hassanalian, M; Throneberry, G; Ali, M; Ben Ayed, S; Abdelkefi, A

    2018-01-01

    Drag reduction of the wings of migrating birds is crucial to their flight efficiency. Wing color impacts absorption of solar irradiation which may affect drag but there is little known in this area. To this end, the drag reduction induced by the thermal effect of the wing color of migrating birds with unpowered flight modes is presented in this study. Considering this natural phenomenon in the albatross as an example of migrating birds, and applying an energy balance for this biological system, a thermal analysis is performed on the wings during the summer and winter to obtain different ranges of air density, viscosity, and wing surface temperature brought about from a range of ambient temperatures and climatic conditions seen in different seasons and to study their effects. The exact shape of the albatross wing is used and nine different wing colors are considered in order to gain a better understanding of the effect different colors' absorptivities make on the change in aerodynamic performances. The thermal effect is found to be more important during the summer than during the winter due to the higher values of solar irradiation and a maximum drag reduction of 7.8% is found in summer changing the wing color from light white to dark black. The obtained results show that albatrosses with darker colored wings are more efficient (constant lift to drag ratio and drag reduction) and have better endurance due to this drag reduction. Copyright © 2017 Elsevier Ltd. All rights reserved.

  3. The functional basis of wing patterning in Heliconius butterflies: the molecules behind mimicry.

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    Kronforst, Marcus R; Papa, Riccardo

    2015-05-01

    Wing-pattern mimicry in butterflies has provided an important example of adaptation since Charles Darwin and Alfred Russell Wallace proposed evolution by natural selection >150 years ago. The neotropical butterfly genus Heliconius played a central role in the development of mimicry theory and has since been studied extensively in the context of ecology and population biology, behavior, and mimicry genetics. Heliconius species are notable for their diverse color patterns, and previous crossing experiments revealed that much of this variation is controlled by a small number of large-effect, Mendelian switch loci. Recent comparative analyses have shown that the same switch loci control wing-pattern diversity throughout the genus, and a number of these have now been positionally cloned. Using a combination of comparative genetic mapping, association tests, and gene expression analyses, variation in red wing patterning throughout Heliconius has been traced back to the action of the transcription factor optix. Similarly, the signaling ligand WntA has been shown to control variation in melanin patterning across Heliconius and other butterflies. Our understanding of the molecular basis of Heliconius mimicry is now providing important insights into a variety of additional evolutionary phenomena, including the origin of supergenes, the interplay between constraint and evolvability, the genetic basis of convergence, the potential for introgression to facilitate adaptation, the mechanisms of hybrid speciation in animals, and the process of ecological speciation. Copyright © 2015 by the Genetics Society of America.

  4. The Functional Basis of Wing Patterning in Heliconius Butterflies: The Molecules Behind Mimicry

    Science.gov (United States)

    Kronforst, Marcus R.; Papa, Riccardo

    2015-01-01

    Wing-pattern mimicry in butterflies has provided an important example of adaptation since Charles Darwin and Alfred Russell Wallace proposed evolution by natural selection >150 years ago. The neotropical butterfly genus Heliconius played a central role in the development of mimicry theory and has since been studied extensively in the context of ecology and population biology, behavior, and mimicry genetics. Heliconius species are notable for their diverse color patterns, and previous crossing experiments revealed that much of this variation is controlled by a small number of large-effect, Mendelian switch loci. Recent comparative analyses have shown that the same switch loci control wing-pattern diversity throughout the genus, and a number of these have now been positionally cloned. Using a combination of comparative genetic mapping, association tests, and gene expression analyses, variation in red wing patterning throughout Heliconius has been traced back to the action of the transcription factor optix. Similarly, the signaling ligand WntA has been shown to control variation in melanin patterning across Heliconius and other butterflies. Our understanding of the molecular basis of Heliconius mimicry is now providing important insights into a variety of additional evolutionary phenomena, including the origin of supergenes, the interplay between constraint and evolvability, the genetic basis of convergence, the potential for introgression to facilitate adaptation, the mechanisms of hybrid speciation in animals, and the process of ecological speciation. PMID:25953905

  5. Wake patterns of the wings and tail of hovering hummingbirds

    Science.gov (United States)

    Altshuler, Douglas L.; Princevac, Marko; Pan, Hansheng; Lozano, Jesse

    The flow fields of slowly flying bats and fasterflying birds differ in that bats produce two vortex loops during each stroke, one per wing, and birds produce a single vortex loop per stroke. In addition, the circulation at stroke transition approaches zero in bats but remains strong in birds. It is unknown if these difference derive from fundamental differences in wing morphology or are a consequence of flight speed. Here, we present an analysis of the horizontal flow field underneath hovering Anna's hummingbirds (Calypte anna) to describe the wake of a bird flying at zero forward velocity. We also consider how the hummingbird tail interacts with the wake generated by the wings. High-speed image recording and analysis from three orthogonal perspectives revealed that the wing tips reach peak velocities in the middle of each stroke and approach zero velocity at stroke transition. Hummingbirds use complex tail kinematic patterns ranging from in phase to antiphase cycling with respect to the wings, covering several phase shifted patterns. We employed particle image velocimetry to attain detailed horizontal flow measurements at three levels with respect to the tail: in the tail, at the tail tip, and just below the tail. The velocity patterns underneath the wings indicate that flow oscillates along the ventral-dorsal axis in response to the down- and up-strokes and that the sideways flows with respect to the bird are consistently from the lateral to medial. The region around the tail is dominated by axial flows in dorsal to ventral direction. We propose that these flows are generated by interaction between the wakes of the two wings at the end of the upstroke, and that the tail actively defects flows to generate moments that contribute to pitch stability. The flow fields images also revealed distinct vortex loops underneath each wing, which were generated during each stroke. From these data, we propose a model for the primary flow structures of hummingbirds that more

  6. Customized color patterning of photovoltaic cells

    Energy Technology Data Exchange (ETDEWEB)

    Cruz-Campa, Jose Luis; Nielson, Gregory N.; Okandan, Murat; Lentine, Anthony L.; Resnick, Paul J.; Gupta, Vipin P.

    2016-11-15

    Photovoltaic cells and photovoltaic modules, as well as methods of making and using such photovoltaic cells and photovoltaic modules, are disclosed. More particularly, embodiments of the photovoltaic cells selectively reflect visible light to provide the photovoltaic cells with a colorized appearance. Photovoltaic modules combining colorized photovoltaic cells may be used to harvest solar energy while providing a customized appearance, e.g., an image or pattern.

  7. Waiting in the wings: what can we learn about gene co-option from the diversification of butterfly wing patterns?

    Science.gov (United States)

    Jiggins, Chris D; Wallbank, Richard W R; Hanly, Joseph J

    2017-02-05

    A major challenge is to understand how conserved gene regulatory networks control the wonderful diversity of form that we see among animals and plants. Butterfly wing patterns are an excellent example of this diversity. Butterfly wings form as imaginal discs in the caterpillar and are constructed by a gene regulatory network, much of which is conserved across the holometabolous insects. Recent work in Heliconius butterflies takes advantage of genomic approaches and offers insights into how the diversification of wing patterns is overlaid onto this conserved network. WntA is a patterning morphogen that alters spatial information in the wing. Optix is a transcription factor that acts later in development to paint specific wing regions red. Both of these loci fit the paradigm of conserved protein-coding loci with diverse regulatory elements and developmental roles that have taken on novel derived functions in patterning wings. These discoveries offer insights into the 'Nymphalid Ground Plan', which offers a unifying hypothesis for pattern formation across nymphalid butterflies. These loci also represent 'hotspots' for morphological change that have been targeted repeatedly during evolution. Both convergent and divergent evolution of a great diversity of patterns is controlled by complex alleles at just a few genes. We suggest that evolutionary change has become focused on one or a few genetic loci for two reasons. First, pre-existing complex cis-regulatory loci that already interact with potentially relevant transcription factors are more likely to acquire novel functions in wing patterning. Second, the shape of wing regulatory networks may constrain evolutionary change to one or a few loci. Overall, genomic approaches that have identified wing patterning loci in these butterflies offer broad insight into how gene regulatory networks evolve to produce diversity.This article is part of the themed issue 'Evo-devo in the genomics era, and the origins of morphological

  8. Biomimetic zinc oxide replica with structural color using butterfly (Ideopsis similis) wings as templates.

    Science.gov (United States)

    Zhang, Wang; Zhang, Di; Fan, Tongxiang; Ding, Jian; Gu, Jiajun; Guo, Qixin; Ogawa, Hiroshi

    2006-09-01

    Nano-structured colorful zinc oxide (ZnO) replicas were produced using the wings of the Ideopsis similis butterfly as templates. The ZnO replicas we obtained exhibit iridescence, which was clearly observed under an optical microscope (OM). Field emission scanning electron microscope analysis shows that all the microstructure details are maintained faithfully in the ZnO replica. A computer model was established to simulate the diffraction spectral results, which agreed well with the OM images.

  9. Artificial selection for structural color on butterfly wings and comparison with natural evolution.

    Science.gov (United States)

    Wasik, Bethany R; Liew, Seng Fatt; Lilien, David A; Dinwiddie, April J; Noh, Heeso; Cao, Hui; Monteiro, Antónia

    2014-08-19

    Brilliant animal colors often are produced from light interacting with intricate nano-morphologies present in biological materials such as butterfly wing scales. Surveys across widely divergent butterfly species have identified multiple mechanisms of structural color production; however, little is known about how these colors evolved. Here, we examine how closely related species and populations of Bicyclus butterflies have evolved violet structural color from brown-pigmented ancestors with UV structural color. We used artificial selection on a laboratory model butterfly, B. anynana, to evolve violet scales from UV brown scales and compared the mechanism of violet color production with that of two other Bicyclus species, Bicyclus sambulos and Bicyclus medontias, which have evolved violet/blue scales independently via natural selection. The UV reflectance peak of B. anynana brown scales shifted to violet over six generations of artificial selection (i.e., in less than 1 y) as the result of an increase in the thickness of the lower lamina in ground scales. Similar scale structures and the same mechanism for producing violet/blue structural colors were found in the other Bicyclus species. This work shows that populations harbor large amounts of standing genetic variation that can lead to rapid evolution of scales' structural color via slight modifications to the scales' physical dimensions.

  10. Pigmentary and photonic coloration mechanisms reveal taxonomic relationships of the Cattlehearts (Lepidoptera: Papilionidae: Parides)

    NARCIS (Netherlands)

    Wilts, Bodo D.; Ijbema, Natasja; Stavenga, Doekele G.

    2014-01-01

    Background: The colorful wing patterns of butterflies, a prime example of biodiversity, can change dramatically within closely related species. Wing pattern diversity is specifically present among papilionid butterflies. Whether a correlation between color and the evolution of these butterflies

  11. Food color, flavor, and conditioned avoidance among red-winged blackbirds.

    Science.gov (United States)

    Werner, Scott J; Kimball, Bruce A; Provenza, Frederick D

    2008-01-28

    The relationship between food flavors and postingestive feedback enables mammalian herbivores to procure nutrients and avoid toxins within ever-changing environments. We conducted four experiments with red-winged blackbirds (Agelaius phoeniceus) in captivity to determine the relative roles of color and flavor cues paired with negative postingestive feedback. We first conducted baseline tests to assess preferences for colors and flavors. All blackbirds preferred red- to blue-colored food, and they preferred umami- (l-alanine) flavored to bitter/astringent food (tannic acid). We observed no difference in consumption of salty (NaCl) vs sour (citric acid) foods during baseline tests (i.e., neutral flavors). We then conditioned experimentally naïve blackbirds with intraperitoneal injections of lithium chloride (LiCl) to avoid food treated with red and l-alanine, or red and NaCl (n=30 birds per conditioning group). Subsequent to conditioning with LiCl, three test groups were established from each conditioned group to evaluate color and flavor preferences, and preferences for novel color-flavor pairings (e.g., red/tannic acid vs blue/l-alanine). Blackbirds avoided red and salty food throughout the 4-day test. Avoidance conditioned with LiCl extinguished for preferred flavors, but not for colors, of food. Conditioning affected indifference for the otherwise preferred flavor and avoidance for the otherwise neutral flavor. Relative to the neutral-flavor conditioning group, the group conditioned with a preferred flavor exhibited stronger conditioned avoidance of colored food. Unlike conditioned flavor avoidance, birds were conditioned to avoid red food only when blue food was made familiar prior to conditioning. Collectively, these results illustrate that blackbirds used affective processes (flavor-feedback relationships) to shift preference for both novel and familiar flavors, and cognitive associations (colors) to avoid food, subsequent to toxin exposure. We discuss the

  12. Wingless is a positive regulator of eyespot color patterns in Bicyclus anynana butterflies.

    Science.gov (United States)

    Özsu, Nesibe; Chan, Qian Yi; Chen, Bin; Gupta, Mainak Das; Monteiro, Antónia

    2017-09-01

    Eyespot patterns of nymphalid butterflies are an example of a novel trait yet, the developmental origin of eyespots is still not well understood. Several genes have been associated with eyespot development but few have been tested for function. One of these genes is the signaling ligand, wingless, which is expressed in the eyespot centers during early pupation and may function in eyespot signaling and color ring differentiation. Here we tested the function of wingless in wing and eyespot development by down-regulating it in transgenic Bicyclus anynana butterflies via RNAi driven by an inducible heat-shock promoter. Heat-shocks applied during larval and early pupal development led to significant decreases in wingless mRNA levels and to decreases in eyespot size and wing size in adult butterflies. We conclude that wingless is a positive regulator of eyespot and wing development in B. anynana butterflies. Copyright © 2017 Elsevier Inc. All rights reserved.

  13. Warning signals are seductive: relative contributions of color and pattern to predator avoidance and mate attraction in Heliconius butterflies.

    Science.gov (United States)

    Finkbeiner, Susan D; Briscoe, Adriana D; Reed, Robert D

    2014-12-01

    Visual signaling in animals can serve many uses, including predator deterrence and mate attraction. In many cases, signals used to advertise unprofitability to predators are also used for intraspecific communication. Although aposematism and mate choice are significant forces driving the evolution of many animal phenotypes, the interplay between relevant visual signals remains little explored. Here, we address this question in the aposematic passion-vine butterfly Heliconius erato by using color- and pattern-manipulated models to test the contributions of different visual features to both mate choice and warning coloration. We found that the relative effectiveness of a model at escaping predation was correlated with its effectiveness at inducing mating behavior, and in both cases wing color was more predictive of presumptive fitness benefits than wing pattern. Overall, however, a combination of the natural (local) color and pattern was most successful for both predator deterrence and mate attraction. By exploring the relative contributions of color versus pattern composition in predation and mate preference studies, we have shown how both natural and sexual selection may work in parallel to drive the evolution of specific animal color patterns. © 2014 The Author(s). Evolution © 2014 The Society for the Study of Evolution.

  14. SEXUAL SELECTION AND SURVIVAL SELECTION ON WING COLORATION AND BODY SIZE IN THE RUBYSPOT DAMSELFLY HETAERINA AMERICANA.

    Science.gov (United States)

    Grether, Gregory F

    1996-10-01

    I review methodological problems that can lead to false evidence for selection on secondary sexual characters and present a study of selection in rubyspot damselflies (Hetaerina americana) that avoids these pitfalls. Male rubyspots have a large red spot on each wing that grows to a terminal size after sexual maturity. Selection gradient analyses revealed evidence for positive sexual and survival selection on both terminal wing spot size and body size. Phenotype manipulations confirmed that wing spot size was subject to direct sexual selection, but showed that the positive slope of survival on wing spot size was an indirect effect of selection on unmeasured traits. This study provides the strongest evidence yet for sexual selection on coloration in Odonata, but also provides clear examples of why phenotypic selection statistics must be calculated and interpreted cautiously. © 1996 The Society for the Study of Evolution.

  15. Wing patterning genes and coevolution of Müllerian mimicry in Heliconius butterflies: Support from phylogeography, cophylogeny, and divergence times.

    Science.gov (United States)

    Hoyal Cuthill, Jennifer F; Charleston, Michael

    2015-12-01

    Examples of long-term coevolution are rare among free-living organisms. Müllerian mimicry in Heliconius butterflies had been suggested as a key example of coevolution by early genetic studies. However, research over the last two decades has been dominated by the idea that the best-studied comimics, H. erato and H. melpomene, did not coevolve at all. Recently sequenced genes associated with wing color pattern phenotype offer a new opportunity to resolve this controversy. Here, we test the hypothesis of coevolution between H. erato and H. melpomene using Bayesian multilocus analysis of five color pattern genes and five neutral genetic markers. We first explore the extent of phylogenetic agreement versus conflict between the different genes. Coevolution is then tested against three aspects of the mimicry diversifications: phylogenetic branching patterns, divergence times, and, for the first time, phylogeographic histories. We show that all three lines of evidence are compatible with strict coevolution of the diverse mimicry wing patterns, contrary to some recent suggestions. Instead, these findings tally with a coevolutionary diversification driven primarily by the ecological force of Müllerian mimicry. © 2015 The Author(s). Evolution © 2015 The Society for the Study of Evolution.

  16. Color filter array pattern identification using variance of color difference image

    Science.gov (United States)

    Shin, Hyun Jun; Jeon, Jong Ju; Eom, Il Kyu

    2017-07-01

    A color filter array is placed on the image sensor of a digital camera to acquire color images. Each pixel uses only one color, since the image sensor can measure only one color per pixel. Therefore, empty pixels are filled using an interpolation process called demosaicing. The original and the interpolated pixels have different statistical characteristics. If the image is modified by manipulation or forgery, the color filter array pattern is altered. This pattern change can be a clue for image forgery detection. However, most forgery detection algorithms have the disadvantage of assuming the color filter array pattern. We present an identification method of the color filter array pattern. Initially, the local mean is eliminated to remove the background effect. Subsequently, the color difference block is constructed to emphasize the difference between the original pixel and the interpolated pixel. The variance measure of the color difference image is proposed as a means of estimating the color filter array configuration. The experimental results show that the proposed method is effective in identifying the color filter array pattern. Compared with conventional methods, our method provides superior performance.

  17. The Lycaenid Central Symmetry System: Color Pattern Analysis of the Pale Grass Blue Butterfly Zizeeria maha.

    Science.gov (United States)

    Iwata, Masaki; Taira, Wataru; Hiyama, Atsuki; Otaki, Joji M

    2015-06-01

    The nymphalid groundplan has been proposed to explain diverse butterfly wing color patterns. In this model, each symmetry system is composed of a core element and a pair of paracore elements. The development of this elemental configuration has been explained by the induction model for positional information. However, the diversity of color patterns in other butterfly families in relation to the nymphalid groundplan has not been thoroughly examined. Here, we examined aberrant color pattern phenotypes of a lycaenid butterfly, Zizeeria maha, from mutagenesis and plasticity studies as well as from field surveys. In several mutants, the third and fourth spot arrays were coordinately positioned much closer to the discal spot in comparison to the normal phenotype. In temperature-shock types, the third and fourth array spots were elongated inwardly or outwardly from their normal positions. In field-caught spontaneous mutants, small black spots were located adjacent to normal black spots. Analysis of these aberrant phenotypes indicated that the spots belonging to the third and fourth arrays are synchronously changeable in position and shape around the discal spot. Thus, these arrays constitute paracore elements of the central symmetry system of the lycaenid butterflies, and the discal spot comprises the core element. These aberrant phenotypes can be explained by the black-inducing signals that propagate from the prospective discal spot, as predicted by the induction model. These results suggest the existence of long-range developmental signals that cover a large area of a wing not only in nymphalid butterflies, but also in lycaenid butterflies.

  18. Low contrast detectability for color patterns variation of display images

    International Nuclear Information System (INIS)

    Ogura, Akio

    1998-01-01

    In recent years, the radionuclide images are acquired in digital form and displayed with false colors for signal intensity. This color scales for signal intensity have various patterns. In this study, low contrast detectability was compared the performance of gray scale cording with three color scales: the hot color scale, prism color scale and stripe color scale. SPECT images of brain phantom were displayed using four color patterns. These printed images and display images were evaluated with ROC analysis. Display images were indicated higher detectability than printed images. The hot scale and gray scale images indicated better Az of ROC than prism scale images because the prism scale images showed higher false positive rate. (author)

  19. On Pattern Formation Mechanisms for Lepidopteran Wing Patterns and Mammalian Coat Markings

    Science.gov (United States)

    Murray, J. D.

    1981-10-01

    The patterns on wings of Lepidoptera can be generated with a few pattern elements, but no mechanism has been suggested for producing them. I consider two of the basic patterns, namely, central symmetry and dependent patterns. A biochemically plausible model mechanism is proposed for generating major aspects of these patterns, based on a diffusing morphogen that activates a gene or colour-specific enzyme in a threshold manner to generate a stable heterogeneous spatial pattern. The model is applied to the determination stream hypothesis of Kuhn & von Engelhardt (Wilhelm Roux Arch. Entw Mech. Org. 130, 660 (1933)), and results from the model compared with their microcautery experiments on the pupal wing of Ephestia kuhniella. In the case of dependent patterns, results are compared with patterns on specific Papilionidae. For the same mechanism and a fixed set of parameters I demonstrate the important roles of geometry and scale on the spatial patterns obtained. The results and evidence presented here suggest the existence of diffusion fields of the order of several millimetres, which are very much larger than most embryonic fields. The existence of zones of polarizing activity is also indicated. Colour patterns on animals are considered to be genetically determined, but the mechanism is not known. I have previously suggested that a single mechanism that can exhibit an infinite variety of patterns is a candidate for that mechanism, and proposed that a reaction-diffusion system that can be diffusively driven unstable could be responsible for the laying down of the spacing patterns that generates the prepattern for animal coat markings. For illustrative purposes I consider a practical reaction mechanism, which exhibits substrate inhibition, and show that the geometry and scale of the domain (part of the epidermis) play a crucial role in the structural patterns that result. Patterns are obtained for a selection of geometries, and general features are related to the coat

  20. Expression of Genes Involved in Drosophila Wing Morphogenesis and Vein Patterning Are Altered by Spaceflight

    Science.gov (United States)

    Parsons-Wingerter, Patricia A.; Hosamani, Ravikumar; Bhattacharya, Sharmila

    2015-01-01

    Imaginal wing discs of Drosophila melanogaster (fruit fly) defined during embryogenesis ultimately result in mature wings of stereotyped (specific) venation patterning. Major regulators of wing disc development are the epidermal growth factor receptor (EGF), Notch, Hedgehog (Hh), Wingless (Wg), and Dpp signaling pathways. Highly stereotyped vascular patterning is also characteristic of tissues in other organisms flown in space such as the mouse retina and leaves of Arabidopsis thaliana. Genetic and other adaptations of vascular patterning to space environmental factors have not yet been systematically quantified, despite widespread recognition of their critical importance for terrestrial and microgravity applications. Here we report changes in gene expression with space flight related to Drosophila wing morphogenesis and vein patterning. In addition, genetically modified phenotypes of increasingly abnormal ectopic wing venation in the Drosophila wing1 were analyzed by NASA's VESsel GENeration Analysis (VESGEN) software2. Our goal is to further develop insightful vascular mappings associated with bioinformatic dimensions of genetic or other molecular phenotypes for correlation with genetic and other molecular profiling relevant to NASA's GeneLab and other Space Biology exploration initiatives.

  1. Evolution of facial color pattern complexity in lemurs.

    Science.gov (United States)

    Rakotonirina, Hanitriniaina; Kappeler, Peter M; Fichtel, Claudia

    2017-11-09

    Interspecific variation in facial color patterns across New and Old World primates has been linked to species recognition and group size. Because group size has opposite effects on interspecific variation in facial color patterns in these two radiations, a study of the third large primate radiation may shed light on convergences and divergences in this context. We therefore compiled published social and ecological data and analyzed facial photographs of 65 lemur species to categorize variation in hair length, hair and skin coloration as well as color brightness. Phylogenetically controlled analyses revealed that group size and the number of sympatric species did not influence the evolution of facial color complexity in lemurs. Climatic factors, however, influenced facial color complexity, pigmentation and hair length in a few facial regions. Hair length in two facial regions was also correlated with group size and may facilitate individual recognition. Since phylogenetic signals were moderate to high for most models, genetic drift may have also played a role in the evolution of facial color patterns of lemurs. In conclusion, social factors seem to have played only a subordinate role in the evolution of facial color complexity in lemurs, and, more generally, group size appears to have no systematic functional effect on facial color complexity across all primates.

  2. Evolution of facial color pattern complexity in lemurs

    OpenAIRE

    Rakotonirina, Hanitriniaina; Kappeler, Peter M.; Fichtel, Claudia

    2017-01-01

    Interspecific variation in facial color patterns across New and Old World primates has been linked to species recognition and group size. Because group size has opposite effects on interspecific variation in facial color patterns in these two radiations, a study of the third large primate radiation may shed light on convergences and divergences in this context. We therefore compiled published social and ecological data and analyzed facial photographs of 65 lemur species to categorize variatio...

  3. Wing pattern variation in the Patagonian biting midge, Forcipomyia (Forcipomyia multipicta Ingram & Macfie (Diptera, Ceratopogonidae

    Directory of Open Access Journals (Sweden)

    Gustavo R. SPINELLI

    2012-01-01

    Full Text Available Examination of the type-series and non-type specimens of the Patagonian biting midge, Forcipomyia (Forcipomyia multipicta Ingram & Macfie (Diptera: Ceratopogonidae, revealed considerable variation in wing patterns of both sexes. One pattern includes several distinct light spot areas, whereas another pattern (e.g, in the holotype only features marginal light spots in cell r3, while other light spots are barely perceptible or absent. The cause(s of the differential lack of dark macrotrichia in certain areas of the wing membrane in specimens of some series could not be attributed either to their age, sex, or method of preservation.

  4. Altitudinal Variability in Wing Patterns of Phyllonorycter salictella (Zeller, 1846 (Lepidoptera: Gracillariidae

    Directory of Open Access Journals (Sweden)

    František Gregor

    2017-01-01

    Full Text Available Individual variability of wing patterns is not frequent in European species of the genus Phyllonorycter Hübner, 1822. It is unusually distinct in Phyllonorycter salictella (Zeller, 1846 which causes some taxonomic ambiguities and oversights. We found on numerous material of adults reared from overwintering pupae collected in the Czech and Slovak Republics since 1950 that this variability is related with altitude (temperature. Adults with the distinct generotypic (plesiomorphic wing patterns dominated in submountain populations while individuals with the strongly reduced (apomorphic wing drawings were represented quite negligibly. This ratio was reversed in lowland populations. The observed variability is continuous between extreme variants, it is regionally and trophic unaffected, and more pronounced in males than in females. The results support the view that the questionable taxa such as Phyllonorycter viminiella (Sircom, 1848 and P. heringiella (Grønlien, 1932 represent only individual (local or regional forms of the above species.

  5. Artificial selection for structural color on butterfly wings and comparison with natural evolution

    OpenAIRE

    Wasik, Bethany R.; Liew, Seng Fatt; Lilien, David A.; Dinwiddie, April J.; Noh, Heeso; Cao, Hui; Monteiro, Antónia

    2014-01-01

    Despite significant efforts to study structural colors in nature, little is known about how such colors and structures evolved in the first place. To address this key question, we performed the first artificial selection (to our knowledge) on a structural color using butterflies. We demonstrated rapid evolution of violet structural color from ultra-violet brown scales in Bicyclus anynana butterflies with only six generations of selection. Furthermore, we identified the structural changes resp...

  6. HIV Testing Patterns among Urban YMSM of Color

    Science.gov (United States)

    Leonard, Noelle R.; Rajan, Sonali; Gwadz, Marya V.; Aregbesola, Temi

    2014-01-01

    The heightened level of risk for HIV infection among Black and Latino young men who have sex with men (YMSM) is driven by multilevel influences. Using cross-sectional data, we examined HIV testing patterns among urban YMSM of color in a high-HIV seroprevalence area (ages 16 to 21 years). Self-reported frequency of testing was high, with 42% of…

  7. Structural Color Patterns by Electrohydrodynamic Jet Printed Photonic Crystals.

    Science.gov (United States)

    Ding, Haibo; Zhu, Cun; Tian, Lei; Liu, Cihui; Fu, Guangbin; Shang, Luoran; Gu, Zhongze

    2017-04-05

    In this work, we demonstrate the fabrication of photonic crystal patterns with controllable morphologies and structural colors utilizing electrohydrodynamic jet (E-jet) printing with colloidal crystal inks. The final shape of photonic crystal units is controlled by the applied voltage signal and wettability of the substrate. Optical properties of the structural color patterns are tuned by the self-assembly of the silica nanoparticle building blocks. Using this direct printing technique, it is feasible to print customized functional patterns composed of photonic crystal dots or photonic crystal lines according to relevant printing mode and predesigned tracks. This is the first report for E-jet printing with colloidal crystal inks. Our results exhibit promising applications in displays, biosensors, and other functional devices.

  8. Pigmentary and photonic coloration mechanisms reveal taxonomic relationships of the Cattlehearts (Lepidoptera: Papilionidae: Parides).

    Science.gov (United States)

    Wilts, Bodo D; IJbema, Natasja; Stavenga, Doekele G

    2014-07-27

    The colorful wing patterns of butterflies, a prime example of biodiversity, can change dramatically within closely related species. Wing pattern diversity is specifically present among papilionid butterflies. Whether a correlation between color and the evolution of these butterflies exists so far remained unsolved. We here investigate the Cattlehearts, Parides, a small Neotropical genus of papilionid butterflies with 36 members, the wings of which are marked by distinctly colored patches. By applying various physical techniques, we investigate the coloration toolkit of the wing scales. The wing scales contain two different, wavelength-selective absorbing pigments, causing pigmentary colorations. Scale ridges with multilayered lamellae, lumen multilayers or gyroid photonic crystals in the scale lumen create structural colors that are variously combined with these pigmentary colors. The pigmentary and structural traits strongly correlate with the taxonomical distribution of Parides species. The experimental findings add crucial insight into the evolution of butterfly wing scales and show the importance of morphological parameter mapping for butterfly phylogenetics.

  9. Gradual and contingent evolutionary emergence of leaf mimicry in butterfly wing patterns.

    Science.gov (United States)

    Suzuki, Takao K; Tomita, Shuichiro; Sezutsu, Hideki

    2014-11-25

    Special resemblance of animals to natural objects such as leaves provides a representative example of evolutionary adaptation. The existence of such sophisticated features challenges our understanding of how complex adaptive phenotypes evolved. Leaf mimicry typically consists of several pattern elements, the spatial arrangement of which generates the leaf venation-like appearance. However, the process by which leaf patterns evolved remains unclear. In this study we show the evolutionary origin and process for the leaf pattern in Kallima (Nymphalidae) butterflies. Using comparative morphological analyses, we reveal that the wing patterns of Kallima and 45 closely related species share the same ground plan, suggesting that the pattern elements of leaf mimicry have been inherited across species with lineage-specific changes of their character states. On the basis of these analyses, phylogenetic comparative methods estimated past states of the pattern elements and enabled reconstruction of the wing patterns of the most recent common ancestor. This analysis shows that the leaf pattern has evolved through several intermediate patterns. Further, we use Bayesian statistical methods to estimate the temporal order of character-state changes in the pattern elements by which leaf mimesis evolved, and show that the pattern elements changed their spatial arrangement (e.g., from a curved line to a straight line) in a stepwise manner and finally establish a close resemblance to a leaf venation-like appearance. Our study provides the first evidence for stepwise and contingent evolution of leaf mimicry.  Leaf mimicry patterns evolved in a gradual, rather than a sudden, manner from a non-mimetic ancestor. Through a lineage of Kallima butterflies, the leaf patterns evolutionarily originated through temporal accumulation of orchestrated changes in multiple pattern elements.

  10. Insights on the thermal impacts of wing colorization of migrating birds on their skin friction drag and the choice of their flight route.

    Science.gov (United States)

    Hassanalian, M; Ayed, S Ben; Ali, M; Houde, P; Hocut, C; Abdelkefi, A

    2018-02-01

    The thermal effects of wing color in flight is investigated in four species of birds with respect to their flight routes, migration time, and geometric and behavioral characteristics. Considering the marine and atmospheric characteristics of these flight routes, a thermal analysis of the birds' wings is performed during their migration. The surrounding fluxes including the ocean flux and the solar irradiance are considered in an energy balance in order to determine the skin temperature of both sides of the wing. Applying the Blasius solution for heated boundary layers, it is shown that the color configuration of these migrating birds, namely black on the top side of the wings and white on the bottom side of the wings ("countershading"), results in a skin drag reduction, if compared to some other configurations, when both day and night are taken into consideration. This drag reduction can be considered as one of the effective factors for long endurance of these migrating birds. This research can provide the evolutionary perspective behind the colorization of these migrating birds. Copyright © 2018 Elsevier Ltd. All rights reserved.

  11. Antibacterial titanium nano-patterned arrays inspired by dragonfly wings

    Science.gov (United States)

    Bhadra, Chris M.; Khanh Truong, Vi; Pham, Vy T. H.; Al Kobaisi, Mohammad; Seniutinas, Gediminas; Wang, James Y.; Juodkazis, Saulius; Crawford, Russell J.; Ivanova, Elena P.

    2015-11-01

    Titanium and its alloys remain the most popular choice as a medical implant material because of its desirable properties. The successful osseointegration of titanium implants is, however, adversely affected by the presence of bacterial biofilms that can form on the surface, and hence methods for preventing the formation of surface biofilms have been the subject of intensive research over the past few years. In this study, we report the response of bacteria and primary human fibroblasts to the antibacterial nanoarrays fabricated on titanium surfaces using a simple hydrothermal etching process. These fabricated titanium surfaces were shown to possess selective bactericidal activity, eliminating almost 50% of Pseudomonas aeruginosa cells and about 20% of the Staphylococcus aureus cells coming into contact with the surface. These nano-patterned surfaces were also shown to enhance the aligned attachment behavior and proliferation of primary human fibroblasts over 10 days of growth. These antibacterial surfaces, which are capable of exhibiting differential responses to bacterial and eukaryotic cells, represent surfaces that have excellent prospects for biomedical applications.

  12. Antibacterial titanium nano-patterned arrays inspired by dragonfly wings

    Science.gov (United States)

    Bhadra, Chris M.; Khanh Truong, Vi; Pham, Vy T. H.; Al Kobaisi, Mohammad; Seniutinas, Gediminas; Wang, James Y.; Juodkazis, Saulius; Crawford, Russell J.; Ivanova, Elena P.

    2015-01-01

    Titanium and its alloys remain the most popular choice as a medical implant material because of its desirable properties. The successful osseointegration of titanium implants is, however, adversely affected by the presence of bacterial biofilms that can form on the surface, and hence methods for preventing the formation of surface biofilms have been the subject of intensive research over the past few years. In this study, we report the response of bacteria and primary human fibroblasts to the antibacterial nanoarrays fabricated on titanium surfaces using a simple hydrothermal etching process. These fabricated titanium surfaces were shown to possess selective bactericidal activity, eliminating almost 50% of Pseudomonas aeruginosa cells and about 20% of the Staphylococcus aureus cells coming into contact with the surface. These nano-patterned surfaces were also shown to enhance the aligned attachment behavior and proliferation of primary human fibroblasts over 10 days of growth. These antibacterial surfaces, which are capable of exhibiting differential responses to bacterial and eukaryotic cells, represent surfaces that have excellent prospects for biomedical applications. PMID:26576662

  13. Order-disorder effects in structure and color relation of photonic-crystal-type nanostructures in butterfly wing scales

    Science.gov (United States)

    Márk, Géza I.; Vértesy, Zofia; Kertész, Krisztián; Bálint, Zsolt; Biró, László P.

    2009-11-01

    In order to study local and global order in butterfly wing scales possessing structural colors, we have developed a direct space algorithm, based on averaging the local environment of the repetitive units building up the structure. The method provides the statistical distribution of the local environments, including the histogram of the nearest-neighbor distance and the number of nearest neighbors. We have analyzed how the different kinds of randomness present in the direct space structure influence the reciprocal space structure. It was found that the Fourier method is useful in the case of a structure randomly deviating from an ordered lattice. The direct space averaging method remains applicable even for structures lacking long-range order. Based on the first Born approximation, a link is established between the reciprocal space image and the optical reflectance spectrum. Results calculated within this framework agree well with measured reflectance spectra because of the small width and moderate refractive index contrast of butterfly scales. By the analysis of the wing scales of Cyanophrys remus and Albulina metallica butterflies, we tested the methods for structures having long-range order, medium-range order, and short-range order.

  14. Variable multilayer reflection together with long-pass filtering pigment determines the wing coloration of papilionid butterflies of the nireus group

    NARCIS (Netherlands)

    Trzeciak, Tomasz M.; Wilts, Bodo D.; Stavenga, Doekele G.; Vukusic, Peter; Sterke, C. Martijn de

    2012-01-01

    The dorsal wing surfaces of papilionid butterflies of the nireus group are marked by bands of brilliant blue-green-colored cover scales. The thin, cuticular lower lamina of the scales acts as a blue reflector. The thick upper lamina forms a dense two-dimensional cuticular lattice of air cavities

  15. Flexible, angle-independent, structural color reflectors inspired by morpho butterfly wings.

    Science.gov (United States)

    Chung, Kyungjae; Yu, Sunkyu; Heo, Chul-Joon; Shim, Jae Won; Yang, Seung-Man; Han, Moon Gyu; Lee, Hong-Seok; Jin, Yongwan; Lee, Sang Yoon; Park, Namkyoo; Shin, Jung H

    2012-05-08

    Thin-film color reflectors inspired by Morpho butterflies are fabricated. Using a combination of directional deposition, silica microspheres with a wide size distribution, and a PDMS (polydimethylsiloxane) encasing, a large, flexible reflector is created that actually provides better angle-independent color characteristics than Morpho butterflies and which can even be bent and folded freely without losing its Morpho-mimetic photonic properties. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  16. Structural Color Model Based on Surface Morphology of MORPHO Butterfly Wing Scale

    Science.gov (United States)

    Huang, Zhongjia; Cai, Congcong; Wang, Gang; Zhang, Hui; Huttula, Marko; Cao, Wei

    2016-05-01

    Color production through structural coloration is created by micrometer and sub-micrometer surface textures which interfere with visible light. The shiny blue of morpho menelaus is a typical example of structural coloring. Modified from morphology of the morpho scale, a structure of regular windows with two side offsets was constructed on glass substrates. Optical properties of the bioinspired structure were studied through numerical simulations of light scattering. Results show that the structure can generate monochromatic light scattering. Wavelength of scattered light is tunable via changing the spacing between window shelves. Compared to original butterfly model, the modified one possesses larger illumination scopes in azimuthal distributions despite being less in polar directions. Present bionic structure is periodically repeated and is easy to fabricate. It is hoped that the computational materials design work can inspire future experimental realizations of such a structure in photonics applications.

  17. Photonic Crystal Structure and Coloration of Wing Scales of Butterflies Exhibiting Selective Wavelength Iridescence

    Czech Academy of Sciences Publication Activity Database

    Mika, Filip; Matějková-Plšková, J.; Jiwajinda, S.; Dechkrong, P.; Shiojiri, M.

    2012-01-01

    Roč. 5, č. 5 (2012), s. 754-771 ISSN 1996-1944 R&D Projects: GA MŠk ED0017/01/01 Institutional support: RVO:68081731 Keywords : butterfly scale * structure color * natural photonic crystal * E. mulciber * S. charonda * C. ataxus * T. aeacus Subject RIV: JJ - Other Materials Impact factor: 2.247, year: 2012

  18. Are color or high rearing density related to migratory polyphenism in the band-winged grasshopper, Oedaleus asiaticus?

    Science.gov (United States)

    Cease, Arianne J; Hao, Shuguang; Kang, Le; Elser, James J; Harrison, Jon F

    2010-08-01

    Locusts represent an impressive example of migratory polyphenism, with high densities triggering a switch from a solitarious, shorter dispersal range, and sometimes greenish phenotype to a gregarious and sometimes darker form exhibiting behavioral, morphological and physiological traits associated with long-distance migratory swarms. While such polyphenism has been well documented in Locusta migratoria and Schistocerca gregaria, the extent to which other grasshoppers exhibit this type of migratory polyphenism is unclear. Anecdotally, the Chinese grasshopper, Oedaleus asiaticus, forms migratory swarms comprised mostly of a darker, brown-colored morph, but also exhibits a non-migratory green-colored morph that predominates at low densities. In a population in Inner Mongolia not currently exhibiting migratory swarms, we found that while green and brown O. asiaticus are found concurrently across our sampled range, only brown grasshoppers were found in high densities. Differences between field-collected brown and green forms matched some but not key predictions associated with the hypothesis that the brown form is morphologically and physiologically specialized for gregarious migration. Controlling for body mass, brown forms had more massive thoraxes, abdomens and legs, and higher metabolic rates, but not more flight muscle or lipid stores. Further, the brown and green grasshoppers did not differ in gregarious behavior, and neither would fly in multiple lab and field trials. Lab or field-rearing at high densities for one-to-multiple juvenile instars caused grasshoppers to exhibit some morphological traits predicted to benefit migration (larger wings and a shift in relative mass from abdomen to thorax), but did not change color or induce flight behavior. One hypothesis to explain these data is that a migratory form of O. asiaticus is partially triggered by high field densities, but that existing ecological conditions blocked full expression of such traits (and outbreak

  19. Tiling patterns from ABC star molecules: 3-colored foams?

    Science.gov (United States)

    Kirkensgaard, Jacob J K; Pedersen, Martin C; Hyde, Stephen T

    2014-10-07

    We present coarse-grained simulations of the self-assembly of 3-armed ABC star polyphiles. In systems of star polyphiles with two arms of equal length the simulations corroborate and expand previous findings from related miktoarm star terpolymer systems on the formation of patterns containing columnar domains whose sections are 2D planar tilings. However, the systematic variation of face topologies as the length of the third (unequal) arm is varied differs from earlier findings regarding the compositional dependence. We explore 2D 3-colored foams to establish the optimal patterns based on interfacial energy alone. A generic construction algorithm is described that accounts for all observed 2D tiling patterns and suggests other patterns likely to be found beyond the range of the simulations reported here. Patterns resulting from this algorithm are relaxed using Surface Evolver calculations to form 2D foams with minimal interfacial length as a function of composition. This allows us to estimate the interfacial enthalpic contributions to the free energy of related star molecular assemblies assuming strong segregation. We compare the resulting phase sequence with a number of theoretical results from particle-based simulations and field theory, allowing us to tease out relative enthalpic and entropic contributions as a function of the chain lengths making up the star molecules. Our results indicate that a richer polymorphism is to be expected in systems not dominated by chain entropy. Further, analysis of corresponding planar tiling patterns suggests that related two-periodic columnar structures are unlikely hypothetical phases in 4-arm star polyphile melts in the absence of sufficient arm configurational freedom for minor domains to form lens-shaped di-gons, which require higher molecular weight polymeric arms. Finally, we discuss the possibility of forming a complex tiling pattern that is a quasi-crystalline approximant for 3-arm star polyphiles with unequal arm

  20. Sex Differences in 20-Hydroxyecdysone Hormone Levels Control Sexual Dimorphism in Bicyclus anynana Wing Patterns.

    Science.gov (United States)

    Bhardwaj, Shivam; Prudic, Kathleen L; Bear, Ashley; Dasgupta, Mainak; Wasik, Bethany R; Tong, Xiaoling; Cheong, Wei Fun; Wenk, Markus R; Monteiro, Antónia

    2018-02-01

    In contrast to the important role of hormones in the development of sexual traits in vertebrates (Cox RM, Stenquist DS, Calsbeek R. 2009. Testosterone, growth and the evolution of sexual size dimorphism. J Evol Biol. 22(8):1586-1598.), the differentiation of these traits in insects is attributed almost exclusively to cell-autonomous mechanisms controlled by members of the sex determination pathway (Verhulst EC, van de Zande L. 2015. Double nexus - doublesex is the connecting element in sex determination. Brief Funct Genomics 14(6):396-406.), such as doublesex. Although hormones can shape the development of sexual traits in insects, variation in hormone levels are not conclusively known to cause dimorphism in these traits (Prakash A, Monteiro A. 2016. Molecular mechanisms of secondary sexual trait development in insects. Curr Opin Insect Sci. 17:40-48.). Here, we show that butterflies use sex-specific differences in 20-hydroxyecdysone hormone titers to create sexually dimorphic wing ornaments. Females of the dry season (DS) form of Bicyclus anynana display a larger sexual ornament on their wings than males, whereas in the wet season form both sexes have similarly sized ornaments (Prudic KL, Jeon C, Cao H, Monteiro A. 2011. Developmental plasticity in sexual roles of butterfly species drives mutual sexual ornamentation. Science 331(6013):73-75.). High levels of circulating 20-hydroxyecdysone during larval development in DS females and wet season forms cause proliferation of the cells fated to give rise to this wing ornament, and results in sexual dimorphism in the DS forms. This study advances our understanding of how the environment regulates sex-specific patterns of plasticity of sexual ornaments and conclusively shows that hormones can play a role in the development of secondary sexual traits in insects, just like they do in vertebrates. © The Author 2017. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

  1. Design Support System for Coloring Illustrations by Using the Colors Preferred by a User as Determined from the Hue Patterns of Illustrations Prepared by that User

    Science.gov (United States)

    Fukai, Hironobu; Mitsukura, Yasue

    We propose a new design support system that can color illustrations according to a person's color preferences that are determined on the basis of the color patterns of illustrations prepared by that person. Recently, many design tools for promoting free design have been developed. However, preferences for various colors differ depending on individual personality. Therefore, a system that can automatically color various designs on the basis of human preference is required. In this study, we propose an automatic modeling system that can be used to model illustrations. To verify the effectiveness of the proposed system, we simulate a coloring design experiment to determine the color patterns preferred by some subjects by using various design data. By using the design data, we determine each subjects preferred color pattern, and send feedback on these individual color patterns to the proposed system.

  2. Wing shape allometry and aerodynamics in calopterygid damselflies: a comparative approach.

    Science.gov (United States)

    Outomuro, David; Adams, Dean C; Johansson, Frank

    2013-06-07

    Wing size and shape have important aerodynamic implications on flight performance. We explored how wing size was related to wing shape in territorial males of 37 taxa of the damselfly family Calopterygidae. Wing coloration was also included in the analyses because it is sexually and naturally selected and has been shown to be related to wing shape. We studied wing shape using both the non-dimensional radius of the second moment of wing area (RSM) and geometric morphometrics. Lower values of the RSM result in less energetically demanding flight and wider ranges of flight speed. We also re-analyzed previously published data on other damselflies and dragonflies. The RSM showed a hump-shaped relationship with wing size. However, after correcting for phylogeny using independent contrast, this pattern changed to a negative linear relationship. The basal genus of the study family, Hetaerina, was mainly driving that change. The obtained patterns were specific for the study family and differed from other damselflies and dragonflies. The relationship between the RSM and wing shape measured by geometric morphometrics was linear, but relatively small changes along the RSM axis can result in large changes in wing shape. Our results also showed that wing coloration may have some effect on RSM. We found that RSM showed a complex relationship with size in calopterygid damselflies, probably as a result of other selection pressures besides wing size per se. Wing coloration and specific behavior (e.g. courtship) are potential candidates for explaining the complexity. Univariate measures of wing shape such as RSM are more intuitive but lack the high resolution of other multivariate techniques such as geometric morphometrics. We suggest that the relationship between wing shape and size are taxa-specific and differ among closely-related insect groups.

  3. Complex dynamics underlie the evolution of imperfect wing pattern convergence in butterflies.

    Science.gov (United States)

    Finkbeiner, Susan D; Briscoe, Adriana D; Mullen, Sean P

    2017-04-01

    Adaptive radiation is characterized by rapid diversification that is strongly associated with ecological specialization. However, understanding the evolutionary mechanisms fueling adaptive diversification requires a detailed knowledge of how natural selection acts at multiple life-history stages. Butterflies within the genus Adelpha represent one of the largest and most diverse butterfly lineages in the Neotropics. Although Adelpha species feed on an extraordinary diversity of larval hosts, convergent evolution is widespread in this group, suggesting that selection for mimicry may contribute to adaptive divergence among species. To investigate this hypothesis, we conducted predation studies in Costa Rica using artificial butterfly facsimiles. Specifically, we predicted that nontoxic, palatable Adelpha species that do not feed on host plants in the family Rubiaceae would benefit from sharing a locally convergent wing pattern with the presumably toxic Rubiaceae-feeding species via reduced predation. Contrary to expectations, we found that the presumed mimic was attacked significantly more than its locally convergent model at a frequency paralleling attack rates on both novel and palatable prey. Although these data reveal the first evidence for protection from avian predators by the supposed toxic, Rubiaceae-feeding Adelpha species, we conclude that imprecise mimetic patterns have high costs for Batesian mimics in the tropics. © 2017 The Author(s). Evolution © 2017 The Society for the Study of Evolution.

  4. A Vision Chip for Color Segmentation and Pattern Matching

    Directory of Open Access Journals (Sweden)

    Ralph Etienne-Cummings

    2003-06-01

    Full Text Available A 128(H × 64(V × RGB CMOS imager is integrated with region-of-interest selection, RGB-to-HSI transformation, HSI-based pixel segmentation, (36bins × 12bits-HSI histogramming, and sum-of-absolute-difference (SAD template matching. Thirty-two learned color templates are stored and compared to each image. The chip captures the R, G, and B images using in-pixel storage before passing the pixel content to a multiplying digital-to-analog converter (DAC for white balancing. The DAC can also be used to pipe in images for a PC. The color processing uses a biologically inspired color opponent representation and an analog lookup table to determine the Hue (H of each pixel. Saturation (S is computed using a loser-take-all circuit. Intensity (I is given by the sum of the color components. A histogram of the segments of the image, constructed by counting the number of pixels falling into 36 Hue intervals of 10 degrees, is stored on a chip and compared against the histograms of new segments using SAD comparisons. We demonstrate color-based image segmentation and object recognition with this chip. Running at 30 fps, it uses 1 mW. To our knowledge, this is the first chip that integrates imaging, color segmentation, and color-based object recognition at the focal plane.

  5. Molecular patterns of X chromosome-linked color vision genes among 134 menof European ancestry

    International Nuclear Information System (INIS)

    Drummond-Borg, M.; Deeb, S.S.; Motulsky, A.G.

    1989-01-01

    The authors used Southern blot hybridization to study X chromosome-linked color vision genes encoding the apoproteins of red and green visual pigments in 134 unselected Caucasian men. One hundred and thirteen individuals (84.3%) had a normal arrangement of their color vision pigment genes. All had one red pigment gene; the number of green pigment genes ranged from one to five with a mode of two. The frequency of molecular genotypes indicative of normal color vision (84.3%) was significantly lower than had been observed in previous studies of color vision phenotypes. Color vision defects can be due to deletions of red or green pigment genes or due to formation of hybrid genes comprising portions of both red and green pigment genes. Characteristic anomalous patterns were seen in 15 (11.2%) individuals: 7 (5.2%) had patterns characteristic of deuteranomaly, 2 (1.5%) had patterns characteristic of deuteranopia, and 6 (4.5%) had protan patterns. Previously undescribed hybrid gene patterns consisting of both green and red pigment gene fragments in addition to normal red and green genes were observed in another 6 individuals (4.5%). Thus, DNA testing detected anomalous color vision pigment genes at a higher frequency than expected from phenotypic color vision tests

  6. The fossil record, function, and possible origins of shell color patterns in Paleozoic marine invertebrates

    Energy Technology Data Exchange (ETDEWEB)

    Kobluk, D.R. (Univ. of Toronto, Ontario (Canada)); Mapes, R.H. (Ohio Univ., Athens (USA))

    1989-02-01

    Fossil invertebrate shells and carapaces displaying preserved original color patterns are among the rarest fossils. The fossil record of color patterns extends into the Middle Cambrian where the trilobite Anomocare displays a fan-like array of stripes on the pygidium. About 180 Paleozic genera are known with patterns, including trilobites, cephalopods, gastropods, brachiopods, bivalves, crinoids, and crustaceans. Based upon an analysis of these taxa, it appears that patterns and pigments in middle and late Paleozoic invertebrates may have served several functions such as warning displays, light screening, camouflage, or waste disposal. However, the presence of color patterns in fossil invertebrates in the early Paleozoic may have developed prior to the evolution of vision sufficiently sophisticated to see them. This suggests that camouflage and warning displays were not the original functions of color patterns, and that in the earliest Paleozoic they may not have been functional. The authors propose a hypothesis that involves three developmental phases in the evolution of invertebrate color patterns: (1) the incorporation of metabolic by-products, perhaps some pigmented and some not pigmented, into shells and carapaces as a means of disposal of dietary or metabolic wastes, (2) use of these pigments and patterns as an environmental adaptation, such as light screening, and (3) display during and following the evolution of vision in predators sufficiently sophisticated to see the patterns.

  7. Patterning between urban soil color and carbon stocks

    Science.gov (United States)

    Schifman, L. A.; Herrmann, D.; Shuster, W.

    2017-12-01

    Urban soils are extensively modified compared to their non-urban counterparts. These modifications are expected to affect the vertical distribution of total soil carbon as well as its constituent pools - soil organic carbon, black carbon, and inorganic carbon. Assigning color to soil horizons using the Munsell color system is a standard field method employed by soil scientists that can also reveal generalizable information about various environmental metrics. A new dataset on urban soils and their reference counterparts that cover 11 regions in the United States and advances in quantitative pedology allowed us to construct a log-linear model that relates Value, the lightness of a color hue, to the concentration of total carbon throughout a soil column of up to 450 cm depth. Overall, the relationship between 671 points resulted in an r2 of 0.23 with a p<0.001. As expected, organic carbon, shifted values to the lower end of the scale (darker), whereas inorganic carbon increased soil color values (lighter). These findings allow for a simplified understanding of shifts in carbon pools throughout a soil profile.

  8. The Effects of Color Patterns on Aggressive Behaviors of a Freshwater Serranid Fish, Coreoperca kawamebari

    OpenAIRE

    Yasutoshi, Kohda; Department of Biology, College of Liberal Arts and Sciences, Okayama University

    1983-01-01

    A freshwater serranid fish, Coreoperca kawamebari, show an intermediate coloration over the entire body with conspicuous eye-like spots when it is motivated aggressively and it displays a striped pattern when motivated in fear. A sexually-motivated female shows a black color over her entire body with a white vertex band. Whether the aggression-releasing effect differs among the aggressive, fear and courting-female patterns was studied using two-dimensional dummies made of paper. The aggressiv...

  9. Fabric Weave Pattern and Yarn Color Recognition and Classification Using a Deep ELM Network

    Directory of Open Access Journals (Sweden)

    Babar Khan

    2017-10-01

    Full Text Available Usually, a fabric weave pattern is recognized using methods which identify the warp floats and weft floats. Although these methods perform well for uniform or repetitive weave patterns, in the case of complex weave patterns, these methods become computationally complex and the classification error rates are comparatively higher. Furthermore, the fault-tolerance (invariance and stability (selectivity of the existing methods are still to be enhanced. We present a novel biologically-inspired method to invariantly recognize the fabric weave pattern (fabric texture and yarn color from the color image input. We proposed a model in which the fabric weave pattern descriptor is based on the HMAX model for computer vision inspired by the hierarchy in the visual cortex, the color descriptor is based on the opponent color channel inspired by the classical opponent color theory of human vision, and the classification stage is composed of a multi-layer (deep extreme learning machine. Since the weave pattern descriptor, yarn color descriptor, and the classification stage are all biologically inspired, we propose a method which is completely biologically plausible. The classification performance of the proposed algorithm indicates that the biologically-inspired computer-aided-vision models might provide accurate, fast, reliable and cost-effective solution to industrial automation.

  10. Estimation of color modification in digital images by CFA pattern change.

    Science.gov (United States)

    Choi, Chang-Hee; Lee, Hae-Yeoun; Lee, Heung-Kyu

    2013-03-10

    Extensive studies have been carried out for detecting image forgery such as copy-move, re-sampling, blurring, and contrast enhancement. Although color modification is a common forgery technique, there is no reported forensic method for detecting this type of manipulation. In this paper, we propose a novel algorithm for estimating color modification in images acquired from digital cameras when the images are modified. Most commercial digital cameras are equipped with a color filter array (CFA) for acquiring the color information of each pixel. As a result, the images acquired from such digital cameras include a trace from the CFA pattern. This pattern is composed of the basic red green blue (RGB) colors, and it is changed when color modification is carried out on the image. We designed an advanced intermediate value counting method for measuring the change in the CFA pattern and estimating the extent of color modification. The proposed method is verified experimentally by using 10,366 test images. The results confirmed the ability of the proposed method to estimate color modification with high accuracy. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

  11. Structural Color Patterns on Paper Fabricated by Inkjet Printer and Their Application in Anticounterfeiting.

    Science.gov (United States)

    Wu, Suli; Liu, Baoqi; Su, Xin; Zhang, Shufen

    2017-07-06

    Inkjet-printed structural color patterns have attracted great attention in recent years because of their broadly promising applications. However, the patterns are usually fabricated on pretreated plastic substrates. Herein a convenient inkjet printing method was developed to fabricate large-scale computer-designed structural color patterns on photo paper without any treatment using inks containing monodisperse CdS spheres. By this strategy, not only were the single-color and multicolor structural color patterns on paper successfully obtained, but also invisible photonic anticounterfeiting was achieved without any external stimuli. The key point of this anticounterfeiting technique is printing patterns and the background with inks containing uniformed CdS spheres with different diameters but similar intrinsic colors, so that the invisible patterns can be observed clearly by simply changing the viewing angle. The invisible and visible can be realized without the change of intrinsic structure, and the patterns are all solids. The patterns will have long lifetime and good durability, which is beneficial for their practical usage.

  12. Transcriptome profiling with focus on potential key genes for wing development and evolution in Megaloprepus caerulatus, the damselfly species with the world's largest wings.

    Science.gov (United States)

    Feindt, Wiebke; Oppenheim, Sara J; DeSalle, Robert; Goldstein, Paul Z; Hadrys, Heike

    2018-01-01

    The evolution, development and coloration of insect wings remains a puzzling subject in evolutionary research. In basal flying insects such as Odonata, genomic research regarding bauplan evolution is still rare. Here we focus on the world's largest odonate species-the "forest giant" Megaloprepus caerulatus, to explore its potential for looking deeper into the development and evolution of wings. A recently discovered cryptic species complex in this genus previously considered monotypic is characterized by morphological differences in wing shape and color patterns. As a first step toward understanding wing pattern divergence and pathways involved in adaptation and speciation at the genomic level, we present a transcriptome profiling of M. caerulatus using RNA-Seq and compare these data with two other odonate species. The de novo transcriptome assembly consists of 61,560 high quality transcripts and is approximately 93% complete. For almost 75% of the identified transcripts a possible function could be assigned: 48,104 transcripts had a hit to an InterPro protein family or domain, and 28,653 were mapped to a Gene Ontology term. In particular, we focused on genes related to wing development and coloration. The comparison with two other species revealed larva-specific genes and a conserved 'core' set of over 8,000 genes forming orthologous clusters with Ischnura elegans and Ladona fulva. This transcriptome may provide a first point of reference for future research in odonates addressing questions surrounding the evolution of wing development, wing coloration and their role in speciation.

  13. The marginal band system in nymphalid butterfly wings.

    Science.gov (United States)

    Taira, Wataru; Kinjo, Seira; Otaki, Joji M

    2015-01-01

    Butterfly wing color patterns are highly complex and diverse, but they are believed to be derived from the nymphalid groundplan, which is composed of several color pattern systems. Among these pattern systems, the marginal band system, including marginal and submarginal bands, has rarely been studied. Here, we examined the color pattern diversity of the marginal band system among nymphalid butterflies. Marginal and submarginal bands are usually expressed as a pair of linear bands aligned with the wing margin. However, a submarginal band can be expressed as a broken band, an elongated oval, or a single dot. The marginal focus, usually a white dot at the middle of a wing compartment along the wing edge, corresponds to the pupal edge spot, one of the pupal cuticle spots that signify the locations of color pattern organizing centers. A marginal band can be expressed as a semicircle, an elongated oval, or a pair of eyespot-like structures, which suggest the organizing activity of the marginal focus. Physical damage at the pupal edge spot leads to distal dislocation of the submarginal band in Junonia almana and in Vanessa indica, suggesting that the marginal focus functions as an organizing center for the marginal band system. Taken together, we conclude that the marginal band system is developmentally equivalent to other symmetry systems. Additionally, the marginal band is likely a core element and the submarginal band a paracore element of the marginal band system, and both bands are primarily specified by the marginal focus organizing center.

  14. The Association of Quantitative Facial Color Features with Cold Pattern in Traditional East Asian Medicine

    Directory of Open Access Journals (Sweden)

    Sujeong Mun

    2017-01-01

    Full Text Available Introduction. Facial diagnosis is a major component of the diagnostic method in traditional East Asian medicine. We investigated the association of quantitative facial color features with cold pattern using a fully automated facial color parameterization system. Methods. The facial color parameters of 64 participants were obtained from digital photographs using an automatic color correction and color parameter calculation system. Cold pattern severity was evaluated using a questionnaire. Results. The a⁎ values of the whole face, lower cheek, and chin were negatively associated with cold pattern score (CPS (whole face: B=-1.048, P=0.021; lower cheek: B=-0.494, P=0.007; chin: B=-0.640, P=0.031, while b⁎ value of the lower cheek was positively associated with CPS (B=0.234, P=0.019. The a⁎ values of the whole face were significantly correlated with specific cold pattern symptoms including cold abdomen (partial ρ=-0.354, P<0.01 and cold sensation in the body (partial ρ=-0.255, P<0.05. Conclusions. a⁎ values of the whole face were negatively associated with CPS, indicating that individuals with increased levels of cold pattern had paler faces. These findings suggest that objective facial diagnosis has utility for pattern identification.

  15. Independently Controlled Wing Stroke Patterns in the Fruit Fly Drosophila melanogaster

    Czech Academy of Sciences Publication Activity Database

    Chakraborty, Soma; Bartussek, Jan; Fry, S.N.; Zápotocký, Martin

    2015-01-01

    Roč. 10, č. 2 (2015), e0116813 E-ISSN 1932-6203 R&D Projects: GA ČR(CZ) GBP304/12/G069 Institutional support: RVO:67985823 Keywords : motor control * wing kinematics * independent component analysis Subject RIV: ED - Physiology Impact factor: 3.057, year: 2015

  16. Nonbreeding isolation and population-specific migration patterns among three populations of Golden-winged Warblers

    Science.gov (United States)

    Kramer, Gunnar R.; Streby, Henry M.; Peterson, Sean M.; Lehman, Justin A.; Buehler, David A.; Wood, Petra; McNeil, Darin J.; Larkin, Jeffrey L.; Andersen, David E.

    2017-01-01

    Golden-winged Warblers (Vermivora chrysoptera) are Nearctic–Neotropical migrants experiencing varied regional population trends not fully explained by breeding-grounds factors such as nest success. A lack of detailed information on the nonbreeding distributions, migration routes, or timing of migration among populations hampers our ability to identify population processes outside the breeding period. We used geolocators to track annual movements of 21 Golden-winged Warblers from 3 North American breeding locations experiencing varying population trends to investigate the potential for nonbreeding site factors to influence breeding populations. We used the template-fit method to estimate locations of individual warblers throughout the year. Geolocator-marked warblers exhibited significant isolation among populations during migration and the nonbreeding period. During the nonbreeding period, Golden-winged Warblers from Minnesota, USA (n = 12) occurred in Central America from southern Mexico to central Nicaragua; warblers from Tennessee, USA (n = 7) occurred along the border of northern Colombia and Venezuela; and warblers from Pennsylvania, USA (n = 2) occurred in north-central Venezuela. Warblers travelled at slower rates over more days in fall migration than spring migration. Fall migration routes at the Gulf of Mexico were population-specific, whereas spring routes were more varied and overlapped among populations. Golden-winged Warblers from Pennsylvania migrated 4,000 and 5,000 km yr−1 farther than Tennessee and Minnesota warblers, respectively, and spent almost twice as long migrating in the fall compared to Minnesota warblers. Our results reveal nearly complete temporal and geographic isolation among 3 populations of Golden-winged Warblers throughout the annual cycle, resulting in opportunities for population- and site-specific factors to differentially influence populations outside the breeding period. Our findings highlight the need for monitoring

  17. The combined effect of two mutations that alter serially homologous color pattern elements on the fore and hindwings of a butterfly

    Directory of Open Access Journals (Sweden)

    Vedder Lindsey

    2007-05-01

    Full Text Available Abstract Background The ability for serially homologous structures to acquire a separate identity has been primarily investigated for structures dependent on Hox gene input but is still incompletely understood in other systems. The fore and hindwings of butterflies are serially homologous structures as are the serially homologous eyespots that can decorate each of these wings. Eyespots can vary in number between fore and hindwings of the same individual and mutations of large effect can control the total number of eyespots that each of the wings displays. Here we investigate the genetics of a new spontaneous color pattern mutation, Missing, that alters eyespot number in the nymphalid butterfly, Bicyclus anynana. We further test the interaction of Missing with a previously described mutation, Spotty, describe the developmental stage affected by Missing, and test whether Missing is a mutant variant of the gene Distal-less via a linkage association study. Results Missing removes or greatly reduces the size of two of the hindwing eyespots from the row of seven eyespots, with no detectable effect on the rest of the wing pattern. Offspring carrying a single Missing allele display intermediate sized eyespots at these positions. Spotty has the opposite effect of Missing, i.e., it introduces two extra eyespots in homologous wing positions to those affected by Missing, but on the forewing. When Missing is combined with Spotty the size of the two forewing eyespots decreases but the size of the hindwing spots stays the same, suggesting that these two mutations have a combined effect on the forewing such that Missing reduces eyespot size when in the presence of a Spotty mutant allele, but that Spotty has no effect on the hindwing. Missing prevents the complete differentiation of two of the eyespot foci on the hindwing. We found no evidence for any linkage between the Distal-less and Missing genes. Conclusion The spontaneous mutation Missing controls the

  18. Identification of the Color Parameters in Pattern Recognition in Real-time Security Systems

    Directory of Open Access Journals (Sweden)

    A. N. Dronov

    2011-03-01

    Full Text Available Problems of identification of the color parameters of moving raster image objects in pattern recognition in modern security systems, which include real-time video-surveillance systems, are declared in this paper. The description of algorithms of identification of the color parameters in frames coming from real-time video streams is given. The practical application of the developed algorithms in program modules of corresponding video systems is demonstrated.

  19. Application of Pattern Recognition Method for Color Assessment of Oriental Tobacco based on HPLC of Polyphenols

    Directory of Open Access Journals (Sweden)

    Dagnon S

    2014-12-01

    Full Text Available The color of Oriental tobaccos was organoleptically assayed, and high performance liquid chromatography (HPLC of polyphenols was performed. The major tobacco polyphenols (chlorogenic acid, its isomers, and rutin, as well as scopoletin and kaempferol-3-rutinoside were quantified. HPLC polyphenol profiles were processed by pattern recognition method (PRM, and the values of indexes of similarity (Is,% between the cultivars studied were determined. It was shown that data from organoleptic color assessment and from PRM based on HPLC profiles of polyphenols of the cultivars studied are largely compatible. Hence, PRM can be suggested as an additional tool for objective color evaluation and classification of Oriental tobacco.

  20. Butterflies regulate wing temperatures using radiative cooling

    Science.gov (United States)

    Tsai, Cheng-Chia; Shi, Norman Nan; Ren, Crystal; Pelaez, Julianne; Bernard, Gary D.; Yu, Nanfang; Pierce, Naomi

    2017-09-01

    Butterfly wings are live organs embedded with multiple sensory neurons and, in some species, with pheromoneproducing cells. The proper function of butterfly wings demands a suitable temperature range, but the wings can overheat quickly in the sun due to their small thermal capacity. We developed an infrared technique to map butterfly wing temperatures and discovered that despite the wings' diverse visible colors, regions of wings that contain live cells are the coolest, resulting from the thickness of the wings and scale nanostructures. We also demonstrated that butterflies use behavioral traits to prevent overheating of their wings.

  1. The colorful brain: Visualization of EEG background patterns

    NARCIS (Netherlands)

    van Putten, Michel Johannes Antonius Maria

    2008-01-01

    This article presents a method to transform routine clinical EEG recordings to an alternative visual domain. The method is intended to support the classic visual interpretation of the EEG background pattern and to facilitate communication about relevant EEG characteristics. In addition, it provides

  2. Median Hetero-Associative Memories Applied to the Categorization of True-Color Patterns

    Science.gov (United States)

    Vázquez, Roberto A.; Sossa, Humberto

    Median associative memories (MED-AMs) are a special type of associative memory based on the median operator. This type of associative model has been applied to the restoration of gray scale images and provides better performance than other models, such as morphological associative memories, when the patterns are altered with mixed noise. Despite of his power, MED-AMs have not been applied in problems involving true-color patterns. In this paper we describe how a median hetero-associative memory (MED-HAM) could be applied in problems that involve true-color patterns. A complete study of the behavior of this associative model in the restoration of true-color images is performed using a benchmark of 14400 images altered by different type of noises. Furthermore, we describe how this model can be applied to an image categorization problem.

  3. Precise colocalization of interacting structural and pigmentary elements generates extensive color pattern variation in Phelsuma lizards

    Science.gov (United States)

    2013-01-01

    Background Color traits in animals play crucial roles in thermoregulation, photoprotection, camouflage, and visual communication, and are amenable to objective quantification and modeling. However, the extensive variation in non-melanic pigments and structural colors in squamate reptiles has been largely disregarded. Here, we used an integrated approach to investigate the morphological basis and physical mechanisms generating variation in color traits in tropical day geckos of the genus Phelsuma. Results Combining histology, optics, mass spectrometry, and UV and Raman spectroscopy, we found that the extensive variation in color patterns within and among Phelsuma species is generated by complex interactions between, on the one hand, chromatophores containing yellow/red pteridine pigments and, on the other hand, iridophores producing structural color by constructive interference of light with guanine nanocrystals. More specifically, we show that 1) the hue of the vivid dorsolateral skin is modulated both by variation in geometry of structural, highly ordered narrowband reflectors, and by the presence of yellow pigments, and 2) that the reflectivity of the white belly and of dorsolateral pigmentary red marks, is increased by underlying structural disorganized broadband reflectors. Most importantly, these interactions require precise colocalization of yellow and red chromatophores with different types of iridophores, characterized by ordered and disordered nanocrystals, respectively. We validated these results through numerical simulations combining pigmentary components with a multilayer interferential optical model. Finally, we show that melanophores form dark lateral patterns but do not significantly contribute to variation in blue/green or red coloration, and that changes in the pH or redox state of pigments provide yet another source of color variation in squamates. Conclusions Precisely colocalized interacting pigmentary and structural elements generate extensive

  4. Diagnostic performance and color overlay pattern in shear wave elastography (SWE) for palpable breast mass.

    Science.gov (United States)

    Park, Jiyoon; Woo, Ok Hee; Shin, Hye Seon; Cho, Kyu Ran; Seo, Bo Kyoung; Kang, Eun Young

    2015-10-01

    The purpose of this study is to evaluate the diagnostic performance of SWE in palpable breast mass and to compare with color overlay pattern in SWE with conventional US and quantitative SWE for assessing palpable breast mass. SWE and conventional breast US were performed in 133 women with 156 palpable breast lesions (81 benign, 75 malignant) between August 2013 to June 2014. Either pathology or periodic imaging surveillance more than 2 years was a reference standard. Existence of previous image was blinded to performing radiologists. US BI-RADS final assessment, qualitative and quantitative SWE measurements were evaluated. Diagnostic performances of grayscale US, SWE and US combined to SWE were calculated and compared. Correlation between pattern classification and quantitative SWE was evaluated. Both color overlay pattern and quantitative SWE improved the specificity of conventional US, from 81.48% to 96.30% (p=0.0005), without improvement in sensitivity. Color overlay pattern was significantly related to all quantitative SWE parameters and malignancy rate (poverlay pattern was between 2 and 3. Emax with optimal cutoff at 45.1 kPa showed the highest Az value, sensitivity, specificity and accuracy among other quantitative SWE parameters (poverlay pattern and pathology (poverlay pattern classification is more quick and easy and may represent quantitative SWE measurements with similar diagnostic performances. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  5. Real-time in vivo imaging of butterfly wing development: revealing the cellular dynamics of the pupal wing tissue.

    Directory of Open Access Journals (Sweden)

    Masaki Iwata

    Full Text Available Butterfly wings are covered with regularly arranged single-colored scales that are formed at the pupal stage. Understanding pupal wing development is therefore crucial to understand wing color pattern formation. Here, we successfully employed real-time in vivo imaging techniques to observe pupal hindwing development over time in the blue pansy butterfly, Junonia orithya. A transparent sheet of epithelial cells that were not yet regularly arranged was observed immediately after pupation. Bright-field imaging and autofluorescent imaging revealed free-moving hemocytes and tracheal branches of a crinoid-like structure underneath the epithelium. The wing tissue gradually became gray-white, epithelial cells were arranged regularly, and hemocytes disappeared, except in the bordering lacuna, after which scales grew. The dynamics of the epithelial cells and scale growth were also confirmed by fluorescent imaging. Fluorescent in vivo staining further revealed that these cells harbored many mitochondria at the surface of the epithelium. Organizing centers for the border symmetry system were apparent immediately after pupation, exhibiting a relatively dark optical character following treatment with fluorescent dyes, as well as in autofluorescent images. The wing tissue exhibited slow and low-frequency contraction pulses with a cycle of approximately 10 to 20 minutes, mainly occurring at 2 to 3 days postpupation. The pulses gradually became slower and weaker and eventually stopped. The wing tissue area became larger after contraction, which also coincided with an increase in the autofluorescence intensity that might have been caused by scale growth. Examination of the pattern of color development revealed that the black pigment was first deposited in patches in the central areas of an eyespot black ring and a parafocal element. These results of live in vivo imaging that covered wide wing area for a long time can serve as a foundation for studying the

  6. Color pattern variation in Cichla temensis (Perciformes: Cichlidae: resolution based on morphological, molecular, and reproductive data

    Directory of Open Access Journals (Sweden)

    Paul Reiss

    Full Text Available Morphological variants of Cichla temensis, readily differentiated by their striking color pattern differences, are found in several Amazon basin flood pulse river systems. The adult variants have at times been thought to represent different species or sexual dimorphism. A three part study was performed in two regions in Brazil (rio Igapó Açú and rio Caures to elucidate the nature of the variants. In part one; selected diagnostic morphometric characters were compared intraspecifically among the variants and interspecifically with C. monoculus and C. orinocensis. All of the C. temensis variants were found to differ significantly from their sympatric congeners while not differing among each other. In part two, mitochondrial DNA samples were compared intraspecifically among the variants and interspecifically with their sympatric congeners. There were no diagnostic molecular synapomorphies that would unambiguously distinguish the variants and all C. temensis variants were clearly diagnosable and divergent from their sympatric congeners. In part three, color pattern variation in both sexes was compared to a gonadosomatic index (GSI. A significant correlation between color pattern variation and gonadosomatic index was found. The results of this study demonstrate that Cichla temensis variants are confirmed to be members of a single species and that the variation does not represent a sexual dimorphism. The color pattern variation is a cyclically occurring secondary sexual characteristic and is indicative of the specific degree of an individual's seasonal sexual maturation.

  7. Visual memory for random block patterns defined by luminance and color contrast

    NARCIS (Netherlands)

    Cornelissen, FW; Greenlee, MW

    2000-01-01

    We studied the ability of human subjects to memorize the visual information in computer-generated random block patterns defined either by luminance contrast, by color contrast, or by both. Memory performance declines rapidly with increasing inter-stimulus interval, showing a half-life of

  8. Heritable variation in garter snake color patterns in postglacial populations.

    Directory of Open Access Journals (Sweden)

    Michael F Westphal

    Full Text Available Global climate change is expected to trigger northward shifts in the ranges of natural populations of plants and animals, with subsequent effects on intraspecific genetic diversity. Investigating how genetic diversity is patterned among populations that arose following the last Ice Age is a promising method for understanding the potential future effects of climate change. Theoretical and empirical work has suggested that overall genetic diversity can decrease in colonial populations following rapid expansion into postglacial landscapes, with potential negative effects on the ability of populations to adapt to new environmental regimes. The crucial measure of this genetic variation and a population's overall adaptability is the heritable variation in phenotypic traits, as it is this variation that mediates the rate and direction of a population's multigenerational response to selection. Using two large full-sib quantitative genetic studies (N(Manitoba = 144; N(South Dakota = 653 and a smaller phenotypic analysis from Kansas (N(Kansas = 44, we compared mean levels of pigmentation, genetic variation and heritability in three pigmentation traits among populations of the common garter snake, Thamnophis sirtalis, along a north-south gradient, including a postglacial northern population and a putative southern refuge population. Counter to our expectations, we found that genetic variance and heritability for the three pigmentation traits were the same or higher in the postglacial population than in the southern population.

  9. Heritable Variation in Garter Snake Color Patterns in Postglacial Populations

    Science.gov (United States)

    Westphal, Michael F.; Massie, Jodi L.; Bronkema, Joanna M.; Smith, Brian E.; Morgan, Theodore J.

    2011-01-01

    Global climate change is expected to trigger northward shifts in the ranges of natural populations of plants and animals, with subsequent effects on intraspecific genetic diversity. Investigating how genetic diversity is patterned among populations that arose following the last Ice Age is a promising method for understanding the potential future effects of climate change. Theoretical and empirical work has suggested that overall genetic diversity can decrease in colonial populations following rapid expansion into postglacial landscapes, with potential negative effects on the ability of populations to adapt to new environmental regimes. The crucial measure of this genetic variation and a population's overall adaptability is the heritable variation in phenotypic traits, as it is this variation that mediates the rate and direction of a population's multigenerational response to selection. Using two large full-sib quantitative genetic studies (NManitoba = 144; NSouth Dakota = 653) and a smaller phenotypic analysis from Kansas (NKansas = 44), we compared mean levels of pigmentation, genetic variation and heritability in three pigmentation traits among populations of the common garter snake, Thamnophis sirtalis, along a north-south gradient, including a postglacial northern population and a putative southern refuge population. Counter to our expectations, we found that genetic variance and heritability for the three pigmentation traits were the same or higher in the postglacial population than in the southern population. PMID:21935386

  10. Pseudo-random arranged color filter array for controlling moiré patterns in display.

    Science.gov (United States)

    Zhou, Yangui; Fan, Hang; An, Sengzhong; Li, Juntao; Wang, Jiahui; Zhou, Jianying; Liu, Yikun

    2015-11-16

    Optical display quality can be degraded by the appearance of moiré pattern occurring in a display system consisting of a basic matrix superimposed with a functional structured optical layer. We propose in this paper a novel pseudo-random arranged color filter array with the table number arranged with an optimal design scenario. We show that the moiré pattern can be significantly reduced with the introduction of the special color filter array. The idea is tested with an experiment that gives rise to a substantially reduced moiré pattern in a display system. It is believed that the novel functional optical structures have significant impact to complex structured display system in general and to the autostereoscopic and integrated display systems in particular.

  11. Intersexual allometry differences and ontogenetic shifts of coloration patterns in two aquatic turtles, Graptemys oculifera and Graptemys flavimaculata.

    Science.gov (United States)

    Ennen, Joshua R; Lindeman, Peter V; Lovich, Jeffrey E

    2015-06-01

    Coloration can play critical roles in a species' biology. The allometry of color patterns may be useful for elucidating the evolutionary mechanisms responsible for shaping the traits. We measured characteristics relating to eight aspects of color patterns from Graptemys oculifera and G. flavimaculata to investigate the allometric differences among male, female, and unsexed juvenile specimens. Additionally, we investigated ontogenetic shifts by incorporating the unsexed juveniles into the male and female datasets. In general, male color traits were isometric (i.e., color scaled with body size), while females and juvenile color traits were hypoallometric, growing in size more slowly than the increase in body size. When we included unsexed juveniles in our male and female datasets, our linear regression analyses found all relationships to be hypoallometric and our model selection analysis found support for nonlinear models describing the relationship between body size and color patterns, suggestive of an ontogenetic shift in coloration traits for both sexes at maturity. Although color is critical for many species' biology and therefore under strong selective pressure in many other species, our results are likely explained by an epiphenomenon related to the different selection pressures on body size and growth rates between juveniles and adults and less attributable to the evolution of color patterns themselves.

  12. Intersexual allometry differences and ontogenetic shifts of coloration patterns in two aquatic turtles, Graptemys oculifera and Graptemys flavimaculata

    Science.gov (United States)

    Ennen, Joshua R.; Lindeman, Peter V.; Lovich, Jeffrey E.

    2015-01-01

    Coloration can play critical roles in a species' biology. The allometry of color patterns may be useful for elucidating the evolutionary mechanisms responsible for shaping the traits. We measured characteristics relating to eight aspects of color patterns from Graptemys oculifera and G. flavimaculata to investigate the allometric differences among male, female, and unsexed juvenile specimens. Additionally, we investigated ontogenetic shifts by incorporating the unsexed juveniles into the male and female datasets. In general, male color traits were isometric (i.e., color scaled with body size), while females and juvenile color traits were hypoallometric, growing in size more slowly than the increase in body size. When we included unsexed juveniles in our male and female datasets, our linear regression analyses found all relationships to be hypoallometric and our model selection analysis found support for nonlinear models describing the relationship between body size and color patterns, suggestive of an ontogenetic shift in coloration traits for both sexes at maturity. Although color is critical for many species' biology and therefore under strong selective pressure in many other species, our results are likely explained by an epiphenomenon related to the different selection pressures on body size and growth rates between juveniles and adults and less attributable to the evolution of color patterns themselves.

  13. Wing shape variation associated with mimicry in butterflies.

    Science.gov (United States)

    Jones, Robert T; Le Poul, Yann; Whibley, Annabel C; Mérot, Claire; ffrench-Constant, Richard H; Joron, Mathieu

    2013-08-01

    Mimetic resemblance in unpalatable butterflies has been studied by evolutionary biologists for over a century, but has largely focused on the convergence in wing color patterns. In Heliconius numata, discrete color-pattern morphs closely resemble comimics in the distantly related genus Melinaea. We examine the possibility that the shape of the butterfly wing also shows adaptive convergence. First, simple measures of forewing dimensions were taken of individuals in a cross between H. numata morphs, and showed quantitative differences between two of the segregating morphs, f. elegans and f. silvana. Second, landmark-based geometric morphometric and elliptical Fourier outline analyses were used to more fully characterize these shape differences. Extension of these techniques to specimens from natural populations suggested that, although many of the coexisting morphs could not be discriminated by shape, the differences we identified between f. elegans and f. silvana hold in the wild. Interestingly, despite extensive overlap, the shape variation between these two morphs is paralleled in their respective Melinaea comimics. Our study therefore suggests that wing-shape variation is associated with mimetic resemblance, and raises the intriguing possibility that the supergene responsible for controlling the major switch in color pattern between morphs also contributes to wing shape differences in H. numata. © 2013 The Author(s). Evolution © 2013 The Society for the Study of Evolution.

  14. Genetic Basis of Body Color and Spotting Pattern in Redheaded Pine Sawfly Larvae (Neodiprion lecontei).

    Science.gov (United States)

    Linnen, Catherine R; O'Quin, Claire T; Shackleford, Taylor; Sears, Connor R; Lindstedt, Carita

    2018-03-01

    Pigmentation has emerged as a premier model for understanding the genetic basis of phenotypic evolution, and a growing catalog of color loci is starting to reveal biases in the mutations, genes, and genetic architectures underlying color variation in the wild. However, existing studies have sampled a limited subset of taxa, color traits, and developmental stages. To expand the existing sample of color loci, we performed quantitative trait locus (QTL) mapping analyses on two types of larval pigmentation traits that vary among populations of the redheaded pine sawfly ( Neodiprion lecontei ): carotenoid-based yellow body color and melanin-based spotting pattern. For both traits, our QTL models explained a substantial proportion of phenotypic variation and suggested a genetic architecture that is neither monogenic nor highly polygenic. Additionally, we used our linkage map to anchor the current N. lecontei genome assembly . With these data, we identified promising candidate genes underlying: (1) a loss of yellow pigmentation in populations in the Mid-Atlantic/northeastern USA [C locus-associated membrane protein homologous to a mammalian HDL receptor-2 gene ( Cameo2 ) and lipid transfer particle apolipoproteins II and I gene ( apoLTP-II/I )], and (2) a pronounced reduction in black spotting in Great-Lakes populations [members of the yellow gene family , tyrosine hydroxylase gene ( pale ) , and dopamine N- acetyltransferase gene ( Dat )]. Several of these genes also contribute to color variation in other wild and domesticated taxa. Overall, our findings are consistent with the hypothesis that predictable genes of large-effect contribute to color evolution in nature. Copyright © 2018, Genetics.

  15. Rapid sympatry explains greater color pattern divergence in high latitude birds.

    Science.gov (United States)

    Martin, Paul R; Montgomerie, Robert; Lougheed, Stephen C

    2010-02-01

    Latitudinal variation in patterns of evolution has fascinated biologists for over a century, but our understanding of latitudinal differences in evolutionary processes-such as selection and drift-remains limited. Here, we test for, and find, accelerated evolution of color patterns in bird taxa that breed at higher latitudes compared with those breeding in the tropics, analyzing data from seven diverse avian families. Most important, we show that the extent of overlap of species' breeding ranges (degree of sympatry) explains the elevated rate of color pattern evolution at higher latitudes. We suggest that the dynamic shifts in breeding ranges that accompanied climatic changes during the last 3 million years (Milankovitch Oscillations) resulted in more rapid and more frequent secondary contact at high latitudes. We argue that sympatry among diverging clades causes greater divergence of color traits in birds at higher latitudes through sexual, social, or ecological character displacement that accelerate rates of evolution, and through the selective elimination of weakly differentiated lineages that hybridize and fuse in sympatry (differential fusion).

  16. Inkjet Printing Based Mono-layered Photonic Crystal Patterning for Anti-counterfeiting Structural Colors

    Science.gov (United States)

    Nam, Hyunmoon; Song, Kyungjun; Ha, Dogyeong; Kim, Taesung

    2016-01-01

    Photonic crystal structures can be created to manipulate electromagnetic waves so that many studies have focused on designing photonic band-gaps for various applications including sensors, LEDs, lasers, and optical fibers. Here, we show that mono-layered, self-assembled photonic crystals (SAPCs) fabricated by using an inkjet printer exhibit extremely weak structural colors and multiple colorful holograms so that they can be utilized in anti-counterfeit measures. We demonstrate that SAPC patterns on a white background are covert under daylight, such that pattern detection can be avoided, but they become overt in a simple manner under strong illumination with smartphone flash light and/or on a black background, showing remarkable potential for anti-counterfeit techniques. Besides, we demonstrate that SAPCs yield different RGB histograms that depend on viewing angles and pattern densities, thus enhancing their cryptographic capabilities. Hence, the structural colorations designed by inkjet printers would not only produce optical holograms for the simple authentication of many items and products but also enable a high-secure anti-counterfeit technique. PMID:27487978

  17. Color Triads in Complex Networks: Uncovering Racial Segregation Patterns in US High Schools

    Science.gov (United States)

    Candia, Julian; Gonzalez, Marta

    2008-03-01

    Introducing color subgraph analysis as a novel tool for characterizing complex network structures, we identify the basic racial patterns in a nationally representative sample of all public and private High Schools in the US. We apply this method on color triad subgraphs and obtain quantitative measurements on racial homophily effects, as well as on interracial mixing patterns. Strongest homophily phenomena are observed within the white student population, followed in decreasing order by black, hispanic and asian students. Racial reciprocity measurements reveal that white students tend to form triads in which they constitute a racial majority. Black-hispanic triads are also observed to be non-reciprocal, while black-asian and hispanic-asian triads show a stronger tendency towards symmetric ties. Racial preference measurements show a rather weak white-black affinity. Since both white and black triad majorities prefer a hispanic third party, hispanic students may play the role of a bridge between white and black students. In order to design better integration strategies, quantitative observations on homophily and interracial mixing patterns could be used to redefine school organizational features. Moreover, the color subgraph analysis method can be applied to a large variety of complex network systems on other interdisciplinary fields of science.

  18. Comparison of the commercial color LCD and the medical monochrome LCD using randomized object test patterns.

    Science.gov (United States)

    Wu, Jay; Wu, Tung H; Han, Rou P; Chang, Shu J; Shih, Cheng T; Sun, Jing Y; Hsu, Shih M

    2012-01-01

    Workstations and electronic display devices in a picture archiving and communication system (PACS) provide a convenient and efficient platform for medical diagnosis. The performance of display devices has to be verified to ensure that image quality is not degraded. In this study, we designed a set of randomized object test patterns (ROTPs) consisting of randomly located spheres with various image characteristics to evaluate the performance of a 2.5 mega-pixel (MP) commercial color LCD and a 3 MP diagnostic monochrome LCD in several aspects, including the contrast, resolution, point spread effect, and noise. The ROTPs were then merged into 120 abdominal CT images. Five radiologists were invited to review the CT images, and receiver operating characteristic (ROC) analysis was carried out using a five-point rating scale. In the high background patterns of ROTPs, the sensitivity performance was comparable between both monitors in terms of contrast and resolution, whereas, in the low background patterns, the performance of the commercial color LCD was significantly poorer than that of the diagnostic monochrome LCD in all aspects. The average area under the ROC curve (AUC) for reviewing abdominal CT images was 0.717±0.0200 and 0.740±0.0195 for the color monitor and the diagnostic monitor, respectively. The observation time (OT) was 145±27.6 min and 127±19.3 min, respectively. No significant differences appeared in AUC (p = 0.265) and OT (p = 0.07). The overall results indicate that ROTPs can be implemented as a quality control tool to evaluate the intrinsic characteristics of display devices. Although there is still a gap in technology between different types of LCDs, commercial color LCDs could replace diagnostic monochrome LCDs as a platform for reviewing abdominal CT images after monitor calibration.

  19. Comparison of the commercial color LCD and the medical monochrome LCD using randomized object test patterns.

    Directory of Open Access Journals (Sweden)

    Jay Wu

    Full Text Available Workstations and electronic display devices in a picture archiving and communication system (PACS provide a convenient and efficient platform for medical diagnosis. The performance of display devices has to be verified to ensure that image quality is not degraded. In this study, we designed a set of randomized object test patterns (ROTPs consisting of randomly located spheres with various image characteristics to evaluate the performance of a 2.5 mega-pixel (MP commercial color LCD and a 3 MP diagnostic monochrome LCD in several aspects, including the contrast, resolution, point spread effect, and noise. The ROTPs were then merged into 120 abdominal CT images. Five radiologists were invited to review the CT images, and receiver operating characteristic (ROC analysis was carried out using a five-point rating scale. In the high background patterns of ROTPs, the sensitivity performance was comparable between both monitors in terms of contrast and resolution, whereas, in the low background patterns, the performance of the commercial color LCD was significantly poorer than that of the diagnostic monochrome LCD in all aspects. The average area under the ROC curve (AUC for reviewing abdominal CT images was 0.717±0.0200 and 0.740±0.0195 for the color monitor and the diagnostic monitor, respectively. The observation time (OT was 145±27.6 min and 127±19.3 min, respectively. No significant differences appeared in AUC (p = 0.265 and OT (p = 0.07. The overall results indicate that ROTPs can be implemented as a quality control tool to evaluate the intrinsic characteristics of display devices. Although there is still a gap in technology between different types of LCDs, commercial color LCDs could replace diagnostic monochrome LCDs as a platform for reviewing abdominal CT images after monitor calibration.

  20. Visual contrast and color in rapid learning of novel patterns by chicks.

    Science.gov (United States)

    Zylinski, S; Osorio, D

    2013-11-15

    Biological communication signals often combine bright and dark colors, such as yellow and black, but it is unclear why such patterns are effective. The literature on aposematism suggests that high contrast patterns may be easily learnt or innately avoided, whereas studies of sexual signaling refer to their attractiveness or to their cost. Here, in experiments with poultry chicks trained to find food in patterned containers, we confirm that elevated contrast dramatically increases the rate of initial attack on novel stimuli, but this response is labile. The chicks pecked once at a novel unrewarded stimulus and then ignored it for at least 24 h. Such single trial learning has not previously been reported for birds without a positively aversive unconditioned stimulus such as quinine. We then tested and rejected two hypotheses about the function of high contrast patterns: first that the preferential responses are due to novelty, and second that elevated contrast enhances learning about a novel color. More generally, the observations are consistent with the idea that elevated contrast attracts attention, thereby enhancing both initial responses - whether positive or negative - and the rate of learning.

  1. Histopathological Image Classification With Color Pattern Random Binary Hashing-Based PCANet and Matrix-Form Classifier.

    Science.gov (United States)

    Shi, Jun; Wu, Jinjie; Li, Yan; Zhang, Qi; Ying, Shihui

    2017-09-01

    The computer-aided diagnosis for histopathological images has attracted considerable attention. Principal component analysis network (PCANet) is a novel deep learning algorithm for feature learning with the simple network architecture and parameters. In this study, a color pattern random binary hashing-based PCANet (C-RBH-PCANet) algorithm is proposed to learn an effective feature representation from color histopathological images. The color norm pattern and angular pattern are extracted from the principal component images of R, G, and B color channels after cascaded PCA networks. The random binary encoding is then performed on both color norm pattern images and angular pattern images to generate multiple binary images. Moreover, we rearrange the pooled local histogram features by spatial pyramid pooling to a matrix-form for reducing the dimension of feature and preserving spatial information. Therefore, a C-RBH-PCANet and matrix-form classifier-based feature learning and classification framework is proposed for diagnosis of color histopathological images. The experimental results on three color histopathological image datasets show that the proposed C-RBH-PCANet algorithm is superior to the original PCANet and other conventional unsupervised deep learning algorithms, while the best performance is achieved by the proposed feature learning and classification framework that combines C-RBH-PCANet and matrix-form classifier.

  2. Plutonium detection in humans using octagonal computer-generated color patterns

    International Nuclear Information System (INIS)

    Phillips, W.G.; Curtis, S.P.

    1985-01-01

    Routine analysis of humans for plutonium lung burdens is accomplished with two phoswich low-energy gamma detectors. The analysis of data from each detector provides the spectroscopist with a total of eight parameters. These parameters are normalized and displayed as an octagonal histogram over laid against the historical analyses of uncontaminated humans similar in body geometry, i.e., weight, height, and chest thickness. Subjects containing lung burdens of plutonium within (one standard deviation) of the historical average yield data which are displayed on a color graphics terminal as a green octagon. Analyses which yield values greater than 1 sigma above the historical average produce a distorted yellow, orange, or red display. Thus, through color and pattern recognition, the analyst may see at a glance if the current data statistically indicate human contamination

  3. Three-dimensional shape profiling by out-of-focus projection of colored pulse width modulation fringe patterns.

    Science.gov (United States)

    Silva, Adriana; Flores, Jorge L; Muñoz, Antonio; Ayubi, Gastón A; Ferrari, José A

    2017-06-20

    Three-dimensional (3D) shape profiling by sinusoidal phase-shifting methods is affected by the non-linearity of the projector. To overcome this problem, the defocusing technique has become an important alternative to generate sinusoidal fringe patterns. The precision of this method depends on the binary pattern used and on the defocusing applied. To improve the defocusing technique, we propose the implementation of a color-based binary fringe patterns. The proposed technique involves the generation of colored pulse width modulation (PWM) fringe patterns, which are generated with different frequencies at the carrier signal. From an adequate selection of these frequencies, the colored PWM fringe patterns will lead to amplitude harmonics lower than the conventional PWM fringe patterns. Hence, the defocusing can decrease, and the 3D shape profiling can be more accurate. Numerical simulations and experimental results are presented as validation.

  4. Colorful patterns indicate common ancestry in diverged tiger beetle taxa: Molecular phylogeny, biogeography, and evolution of elytral coloration of the genus Cicindela subgenus Sophiodela and its allies.

    Science.gov (United States)

    Tsuji, Kaoru; Hori, Michio; Phyu, Moe Hnin; Liang, Hongbin; Sota, Teiji

    2016-02-01

    We investigated the phylogenetic relationships among tiger beetles of the subtribe Cicindelina (=Cicindela s. lat.; Coleoptera: Cicindelidae) mainly from the Oriental and Sino-Japanese zoogeographic regions using one mitochondrial and three nuclear gene sequences to examine the position of the subgenus Sophiodela, currently classified in the genus Cicindela s. str., their biogeography, and the evolution of their brilliant coloration. The subgenus Sophiodela was not related to the other subgenera of Cicindela s. str. but was closely related to the genus Cosmodela. In addition, the Oriental genus Calochroa was polyphyletic with three lineages, one of which was closely related to Sophiodela and Cosmodela. The clade comprising Sophiodela, Cosmodela and two Calochroa species, referred to here as the Sophiodela group, was strongly supported, and most species in this clade had similar brilliant coloration. The Sophiodela group was related to the genera Calomera, Cicindela (excluding Sophiodela) and Cicindelidia, and these were related to Lophyra, Hipparidium and Calochroa, except species in the Sophiodela group. Divergence time estimation suggested that these worldwide Cicindelina groups diverged in the early Oligocene, and the Sophiodela group, which is found in the Oriental and Sino-Japanese zoogeographic regions, in the mid Miocene. Some components of the elytral pattern related to maculation and coloration in the Cicindelina taxa studied contained weak, but significant, phylogenetic signals and were partly associated with habitat types. Therefore, the brilliant coloration of the Sophiodela was related to both phylogeny and habitat adaptation, although the function of coloration needs to be studied. Copyright © 2015 Elsevier Inc. All rights reserved.

  5. Melanin pigmentation gives rise to black spots on the wings of the silkworm Bombyx mori.

    Science.gov (United States)

    Ito, Katsuhiko; Yoshikawa, Manabu; Fujii, Takeshi; Tabunoki, Hiroko; Yokoyama, Takeshi

    2016-01-01

    Several mutants of the silkworm Bombyx mori show body color variation at the larval and adult stages. The Wild wing spot (Ws) mutant exhibits a phenotype in which the moth has a spot on the apex of the forewing. In this study, we investigated this trait to elucidate the molecular mechanism underlying the color pattern. Microscopy of the black spot of Ws mutants showed that the pigment emerges in the scales of the wing, and accumulation of the pigment becomes strong just before eclosion. We next examined the relationship between the black spot of the Ws mutant and melanin. The spectrophotometry using alkaline extracts from the black spot in the wing showed the highest absorption intensity at 405nm, which is the absorbance wavelength of melanin. Moreover, inhibition assays for enzymes implicated in melanin synthesis using 3-iodo-l-tyrosine (a tyrosine hydroxylase inhibitor) and L-α-methyl-DOPA (a dopa decarboxylase inhibitor) revealed that treatment with each inhibitor disrupted the pigmentation of the wing of the Ws mutant. On the basis of these results, we analyzed the expression pattern of five genes involved in melanin formation, and found that the expression levels of yellow and laccase2 were increased just before pigmentation, whereas those of DDC, tan, and TH were increased when the apex of the wing turned black. These results showed that melanin pigmentation gives rise to the black spot on the wing. Copyright © 2016 Elsevier Ltd. All rights reserved.

  6. Drag Performance of Twist Morphing MAV Wing

    Directory of Open Access Journals (Sweden)

    Ismail N.I.

    2016-01-01

    Full Text Available Morphing wing is one of latest evolution found on MAV wing. However, due to few design problems such as limited MAV wing size and complicated morphing mechanism, the understanding of its aerodynamic behaviour was not fully explored. In fact, the basic drag distribution induced by a morphing MAV wing is still remained unknown. Thus, present work is carried out to compare the drag performance between a twist morphing wing with membrane and rigid MAV wing design. A quasi-static aeroelastic analysis by using the Ansys-Fluid Structure Interaction (FSI method is utilized in current works to predict the drag performance a twist morphing MAV wing design. Based on the drag pattern study, the results exhibits that the morphing wing has a partial similarities in overall drag pattern with the baseline (membrane and rigid wing. However, based CD analysis, it shows that TM wing induced higher CD magnitude (between 25% to 82% higher than to the baseline wing. In fact, TM wing also induced the largest CD increment (about 20% to 27% among the wings. The visualization on vortex structure revealed that TM wing also produce larger tip vortex structure (compared to baseline wings which presume to promote higher induce drag component and subsequently induce its higher CD performance.

  7. Black Layers of Decay and Color Patterns on Heritage Limestone as Markers of Environmental Change

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    Elena Mercedes Perez-Monserrat

    2016-01-01

    Full Text Available Air pollution induces the development of black crusts on the surface of built heritage materials. Black layers on the limestone used on an emblematic Madrilenian building dating from the early twentieth century, mainly built up in the 20 years lapsing between two façade cleaning operations, was studied with POM and SEM-EDS. Particulate matter deposited on surfaces in the same period was analyzed with XRD and IC. Climate change in the environs was also studied and façade coloring patterns were compared. Since black crust and settled dust composition, as well as façade soling intensity, were found to be closely related to the surrounding environment, both are proposed as environment and climate change markers. These are considerations, moreover, that must be addressed when designing conservation strategies. Domestic heating systems and vehicle traffic were identified as the two main sources of pollution throughout the period studied in the target area, where the temperature steadily rose and relative humidity declined. The progressive replacement of coal with gas oil in domestic heating boilers and the proliferation of vehicles with diesel engines have mostly determined the evolution of the pollutants emitted. The color of façade soiling, in turn, has been primarily conditioned by the typology of the particles deposited on the limestone surface, declining humidity and the passage of time.

  8. Courtship display dynamics, iridescent structural color and nanostructural pattern formation in ocellated pheasants

    Science.gov (United States)

    Kane, Suzanne Amador; Dakin, Roslyn; Fang, Rui; Lu, Yabin

    Peacocks court females by tilting a fan-like array of feathers decorated with multicolored eyespots (ocelli). Previous research has shown that half of the variation in peacock mating success can be attributed to eyespot iridescence. Several closely-related pheasant species perform similar, but less complex, courtship displays using ocellated feathers with less complex coloration, patterns and underlying nanostructures. This study explores the relationship between the dynamics of male courtship behavior and optical properties and nanostructure of each species' iridescent feather ornaments. In particular, we examined videos of courting males and of individual feathers to measure how the angles used during displays compared to those corresponding to optimal eyespot reflected intensity and iridescent contrast. Bidirectional reflectance spectroscopy was used to measure how the spectrum of reflected light depends on the characteristic angles used during displays, and hence how displays stimulate the four classes of cones found in the color vision systems of these birds. This work reveals a close correlation between the complexity of the angular dependence of iridescent feather reflectance properties and that of the motions used by males of each species.

  9. Longwing (Heliconius) butterflies combine a restricted set of pigmentary and structural coloration mechanisms.

    Science.gov (United States)

    Wilts, Bodo D; Vey, Aidan J M; Briscoe, Adriana D; Stavenga, Doekele G

    2017-11-21

    Longwing butterflies, Heliconius sp., also called heliconians, are striking examples of diversity and mimicry in butterflies. Heliconians feature strongly colored patterns on their wings, arising from wing scales colored by pigments and/or nanostructures, which serve as an aposematic signal. Here, we investigate the coloration mechanisms among several species of Heliconius by applying scanning electron microscopy, (micro)spectrophotometry, and imaging scatterometry. We identify seven kinds of colored scales within Heliconius whose coloration is derived from pigments, nanostructures or both. In yellow-, orange- and red-colored wing patches, both cover and ground scales contain wavelength-selective absorbing pigments, 3-OH-kynurenine, xanthommatin and/or dihydroxanthommatin. In blue wing patches, the cover scales are blue either due to interference of light in the thin-film lower lamina (e.g., H. doris) or in the multilayered lamellae in the scale ridges (so-called ridge reflectors, e.g., H. sara and H. erato); the underlying ground scales are black. In the white wing patches, both cover and ground scales are blue due to their thin-film lower lamina, but because they are stacked upon each other and at the wing substrate, a faint bluish to white color results. Lastly, green wing patches (H. doris) have cover scales with blue-reflecting thin films and short-wavelength absorbing 3-OH-kynurenine, together causing a green color. The pigmentary and structural traits are discussed in relation to their phylogenetic distribution and the evolution of vision in this highly interesting clade of butterflies.

  10. Individually unique body color patterns in octopus (Wunderpus photogenicus) allow for photoidentification.

    Science.gov (United States)

    Huffard, Christine L; Caldwell, Roy L; DeLoach, Ned; Gentry, David Wayne; Humann, Paul; MacDonald, Bill; Moore, Bruce; Ross, Richard; Uno, Takako; Wong, Stephen

    2008-01-01

    Studies on the longevity and migration patterns of wild animals rely heavily on the ability to track individual adults. Non-extractive sampling methods are particularly important when monitoring animals that are commercially important to ecotourism, and/or are rare. The use of unique body patterns to recognize and track individual vertebrates is well-established, but not common in ecological studies of invertebrates. Here we provide a method for identifying individual Wunderpus photogenicus using unique body color patterns. This charismatic tropical octopus is commercially important to the underwater photography, dive tourism, and home aquarium trades, but is yet to be monitored in the wild. Among the adults examined closely, the configurations of fixed white markings on the dorsal mantle were found to be unique. In two animals kept in aquaria, these fixed markings were found not to change over time. We believe another individual was photographed twice in the wild, two months apart. When presented with multiple images of W. photogenicus, volunteer observers reliably matched photographs of the same individuals. Given the popularity of W. photogenicus among underwater photographers, and the ease with which volunteers can correctly identify individuals, photo-identification appears to be a practical means to monitor individuals in the wild.

  11. Individually unique body color patterns in octopus (Wunderpus photogenicus allow for photoidentification.

    Directory of Open Access Journals (Sweden)

    Christine L Huffard

    Full Text Available Studies on the longevity and migration patterns of wild animals rely heavily on the ability to track individual adults. Non-extractive sampling methods are particularly important when monitoring animals that are commercially important to ecotourism, and/or are rare. The use of unique body patterns to recognize and track individual vertebrates is well-established, but not common in ecological studies of invertebrates. Here we provide a method for identifying individual Wunderpus photogenicus using unique body color patterns. This charismatic tropical octopus is commercially important to the underwater photography, dive tourism, and home aquarium trades, but is yet to be monitored in the wild. Among the adults examined closely, the configurations of fixed white markings on the dorsal mantle were found to be unique. In two animals kept in aquaria, these fixed markings were found not to change over time. We believe another individual was photographed twice in the wild, two months apart. When presented with multiple images of W. photogenicus, volunteer observers reliably matched photographs of the same individuals. Given the popularity of W. photogenicus among underwater photographers, and the ease with which volunteers can correctly identify individuals, photo-identification appears to be a practical means to monitor individuals in the wild.

  12. Individually Unique Body Color Patterns in Octopus (Wunderpus photogenicus) Allow for Photoidentification

    Science.gov (United States)

    Huffard, Christine L.; Caldwell, Roy L.; DeLoach, Ned; Gentry, David Wayne; Humann, Paul; MacDonald, Bill; Moore, Bruce; Ross, Richard; Uno, Takako; Wong, Stephen

    2008-01-01

    Studies on the longevity and migration patterns of wild animals rely heavily on the ability to track individual adults. Non-extractive sampling methods are particularly important when monitoring animals that are commercially important to ecotourism, and/or are rare. The use of unique body patterns to recognize and track individual vertebrates is well-established, but not common in ecological studies of invertebrates. Here we provide a method for identifying individual Wunderpus photogenicus using unique body color patterns. This charismatic tropical octopus is commercially important to the underwater photography, dive tourism, and home aquarium trades, but is yet to be monitored in the wild. Among the adults examined closely, the configurations of fixed white markings on the dorsal mantle were found to be unique. In two animals kept in aquaria, these fixed markings were found not to change over time. We believe another individual was photographed twice in the wild, two months apart. When presented with multiple images of W. photogenicus, volunteer observers reliably matched photographs of the same individuals. Given the popularity of W. photogenicus among underwater photographers, and the ease with which volunteers can correctly identify individuals, photo-identification appears to be a practical means to monitor individuals in the wild. PMID:19009019

  13. Experimental studies of vertical mixing patterns in open channel flow generated by two delta wings side-by-side

    Science.gov (United States)

    Vaughan, Garrett

    Open channel raceway bioreactors are a low-cost system used to grow algae for biofuel production. Microalgae have many promises when it comes to renewable energy applications, but many economic hurdles must be overcome to achieve an economic fuel source that is competitive with petroleum-based fuels. One way to make algae more competitive is to improve vertical mixing in algae raceway bioreactors. Previous studies show that mixing may be increased by the addition of mechanisms such as airfoils. The circulation created helps move the algae from the bottom to top surface for necessary photosynthetic exchange. This improvement in light utilization allowed a certain study to achieve 2.2-2.4 times the amount of biomass relative to bioreactors without airfoils. This idea of increasing mixing in open channel raceways has been the focus of the Utah State University (USU) raceway hydraulics group. Computational Fluid Dynamics (CFD), Acoustic Doppler Velocimetry (ADV), and Particle Image Velocimetry (PIV) are all methods used at USU to computationally and experimentally quantify mixing in an open channel raceway. They have also been used to observe the effects of using delta wings (DW) in increasing vertical mixing in the raceway. These efforts showed great potential in the DW in increasing vertical mixing in the open channel bioreactor. However, this research begged the question, does the DW help increase algae growth? Three algae growth experiments comparing growth in a raceway with and without DW were completed. These experiments were successful, yielding an average 27.1% increase in the biomass. The DW appears to be a promising method of increasing algae biomass production. The next important step was to quantify vertical mixing and understand flow patterns due to two DWs side-by-side. Raceway channels are wider as they increase in size; and arrays of DWs will need to be installed to achieve quality mixing throughout the bioreactor. Quality mixing was attained for

  14. Spatial reflection patterns of iridescent wings of male pierid butterflies : Curved scales reflect at a wider angle than flat scales

    NARCIS (Netherlands)

    Pirih, Primož; Wilts, Bodo D.; Stavenga, Doekele G.

    2011-01-01

    The males of many pierid butterflies have iridescent wings, which presumably function in intraspecific communication. The iridescence is due to nanostructured ridges of the cover scales. We have studied the iridescence in the males of a few members of Coliadinae, Gonepteryx aspasia, G. cleopatra, G.

  15. Effects of wing locations on wing rock induced by forebody vortices

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    Ma Baofeng

    2016-10-01

    Full Text Available Previous studies have shown that asymmetric vortex wakes over slender bodies exhibit a multi-vortex structure with an alternate arrangement along a body axis at high angle of attack. In this investigation, the effects of wing locations along a body axis on wing rock induced by forebody vortices was studied experimentally at a subcritical Reynolds number based on a body diameter. An artificial perturbation was added onto the nose tip to fix the orientations of forebody vortices. Particle image velocimetry was used to identify flow patterns of forebody vortices in static situations, and time histories of wing rock were obtained using a free-to-roll rig. The results show that the wing locations can affect significantly the motion patterns of wing rock owing to the variation of multi-vortex patterns of forebody vortices. As the wing locations make the forebody vortices a two-vortex pattern, the wing body exhibits regularly divergence and fixed-point motion with azimuthal variations of the tip perturbation. If a three-vortex pattern exists over the wing, however, the wing-rock patterns depend on the impact of the highest vortex and newborn vortex. As the three vortices together influence the wing flow, wing-rock patterns exhibit regularly fixed-points and limit-cycled oscillations. With the wing moving backwards, the newborn vortex becomes stronger, and wing-rock patterns become fixed-points, chaotic oscillations, and limit-cycled oscillations. With further backward movement of wings, the vortices are far away from the upper surface of wings, and the motions exhibit divergence, limit-cycled oscillations and fixed-points. For the rearmost location of the wing, the wing body exhibits stochastic oscillations and fixed-points.

  16. Human V4 Activity Patterns Predict Behavioral Performance in Imagery of Object Color.

    Science.gov (United States)

    Bannert, Michael M; Bartels, Andreas

    2018-04-11

    Color is special among basic visual features in that it can form a defining part of objects that are engrained in our memory. Whereas most neuroimaging research on human color vision has focused on responses related to external stimulation, the present study investigated how sensory-driven color vision is linked to subjective color perception induced by object imagery. We recorded fMRI activity in male and female volunteers during viewing of abstract color stimuli that were red, green, or yellow in half of the runs. In the other half we asked them to produce mental images of colored, meaningful objects (such as tomato, grapes, banana) corresponding to the same three color categories. Although physically presented color could be decoded from all retinotopically mapped visual areas, only hV4 allowed predicting colors of imagined objects when classifiers were trained on responses to physical colors. Importantly, only neural signal in hV4 was predictive of behavioral performance in the color judgment task on a trial-by-trial basis. The commonality between neural representations of sensory-driven and imagined object color and the behavioral link to neural representations in hV4 identifies area hV4 as a perceptual hub linking externally triggered color vision with color in self-generated object imagery. SIGNIFICANCE STATEMENT Humans experience color not only when visually exploring the outside world, but also in the absence of visual input, for example when remembering, dreaming, and during imagery. It is not known where neural codes for sensory-driven and internally generated hue converge. In the current study we evoked matching subjective color percepts, one driven by physically presented color stimuli, the other by internally generated color imagery. This allowed us to identify area hV4 as the only site where neural codes of corresponding subjective color perception converged regardless of its origin. Color codes in hV4 also predicted behavioral performance in an

  17. Color patterns of the hermit crab Calcinus tibicen (Herbst, 1791 fail to indicate high genetic variation within COI gene

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    Silvia Sayuri Mandai

    2018-03-01

    Full Text Available Abstract Apart from traditional characters, other data have been used for taxonomy, like color patterns. Based on the different colors (green and orange observed for some Calcinus tibicen (Herbst, 1761 specimens, we evaluated the genetic distance for cytochrome oxidase subunit I mitochondrial gene of individuals collected in Pernambuco (northern Brazil and in São Paulo (southeast Brazil. We found low genetic variation (0.2-1.1%, and no evidence of isolation on our molecular tree based on genetic distance. We suggest high levels of gene flow between specimens with different color patterns, which are polymorphisms and might be related to the kind of nutrition as well different ecological and evolutionary predation characteristics.

  18. Usage patterns of blue flower color representation by Encyclopedia of Life content providers.

    Science.gov (United States)

    Wright, Chantal-Marie; Seltmann, Katja C

    2014-01-01

    Encyclopedia of Life (EOL) is a resource for community-driven biodiversity data, focusing on species information and images. Research into blue flowers to compare color ('blueness') at different elevations revealed that data content providers describe flowers as blue for any color hue in the range from blue to magenta. We propose methods for standardizing color values and color searching within EOL by means of an expanded color vocabulary and improved access to image metadata, in order to improve the research capacity of this valuable resource.

  19. A comparison of facial color pattern and gazing behavior in canid species suggests gaze communication in gray wolves (Canis lupus).

    Science.gov (United States)

    Ueda, Sayoko; Kumagai, Gaku; Otaki, Yusuke; Yamaguchi, Shinya; Kohshima, Shiro

    2014-01-01

    As facial color pattern around the eyes has been suggested to serve various adaptive functions related to the gaze signal, we compared the patterns among 25 canid species, focusing on the gaze signal, to estimate the function of facial color pattern in these species. The facial color patterns of the studied species could be categorized into the following three types based on contrast indices relating to the gaze signal: A-type (both pupil position in the eye outline and eye position in the face are clear), B-type (only the eye position is clear), and C-type (both the pupil and eye position are unclear). A-type faces with light-colored irises were observed in most studied species of the wolf-like clade and some of the red fox-like clade. A-type faces tended to be observed in species living in family groups all year-round, whereas B-type faces tended to be seen in solo/pair-living species. The duration of gazing behavior during which the facial gaze-signal is displayed to the other individual was longest in gray wolves with typical A-type faces, of intermediate length in fennec foxes with typical B-type faces, and shortest in bush dogs with typical C-type faces. These results suggest that the facial color pattern of canid species is related to their gaze communication and that canids with A-type faces, especially gray wolves, use the gaze signal in conspecific communication.

  20. A comparison of facial color pattern and gazing behavior in canid species suggests gaze communication in gray wolves (Canis lupus.

    Directory of Open Access Journals (Sweden)

    Sayoko Ueda

    Full Text Available As facial color pattern around the eyes has been suggested to serve various adaptive functions related to the gaze signal, we compared the patterns among 25 canid species, focusing on the gaze signal, to estimate the function of facial color pattern in these species. The facial color patterns of the studied species could be categorized into the following three types based on contrast indices relating to the gaze signal: A-type (both pupil position in the eye outline and eye position in the face are clear, B-type (only the eye position is clear, and C-type (both the pupil and eye position are unclear. A-type faces with light-colored irises were observed in most studied species of the wolf-like clade and some of the red fox-like clade. A-type faces tended to be observed in species living in family groups all year-round, whereas B-type faces tended to be seen in solo/pair-living species. The duration of gazing behavior during which the facial gaze-signal is displayed to the other individual was longest in gray wolves with typical A-type faces, of intermediate length in fennec foxes with typical B-type faces, and shortest in bush dogs with typical C-type faces. These results suggest that the facial color pattern of canid species is related to their gaze communication and that canids with A-type faces, especially gray wolves, use the gaze signal in conspecific communication.

  1. Complete and rapid reversal of the body color pattern in juveniles of the convict surgeonfish Acanthurus triostegus at Moorea Island (French Polynesia)

    Science.gov (United States)

    Besson, Marc; Salis, Pauline; Laudet, Vincent; Lecchini, David

    2018-03-01

    Color polymorphism is widespread in animals and can be associated with temporary adjustments to environmental variables (phenotypic plasticity). In teleost fishes, one of the most remarkable examples of color plasticity is background adaptation in flatfishes. However, such rapid and complete changes in body color and pattern remain relatively unreported in other species. The convict surgeonfish Acanthurus triostegus is a gregarious species whose body color pattern consists of black vertical bars on a whitish body. Here, we describe an entirely reverse body color pattern (white vertical bars on a blackish body) that we observed in some A. triostegus juveniles in a nursery area at Moorea Island, French Polynesia. In aquaria, we determined that change from one color pattern to the other is rapid, reversible, and corresponds to phenotypic plasticity associated with aggressive behavior.

  2. Long-term magnetic activity in close binary systems. I. Patterns of color variations

    Science.gov (United States)

    Messina, S.

    2008-03-01

    Aims:This is the first of a series of papers in which we present the results of a long-term photometric monitoring project carried out at Catania Astrophysical Observatory aimed at studying magnetic activity in late-type components of close binary systems, its dependence on global stellar parameters, and its evolution on different time scales from days to years. In this first paper, we present the complete observation dataset and new results of an investigation into the origin of brightness and color variations observed in the well-known magnetically active close binary stars: AR Psc, VY Ari, UX Ari, V711 Tau, EI Eri, V1149 Ori, DH Leo, HU Vir, RS CVn, V775 Her, AR Lac, SZ Psc, II Peg and BY Dra Methods: About 38 000 high-precision photoelectric nightly observations in the U, B and V filters are analysed. Correlation and regression analyses of the V magnitude vs. U-B and B-V color variations are carried out and a comparison with model variations for a grid of active region temperature and filling factor values is also performed. Results: We find the existence of two different patterns of color variation. Eight stars in our sample: BY Dra, VY Ari, V775 Her, II Peg, V1149 Ori, HU Vir, EI Eri and DH Leo become redder when they become fainter, as is expected from the presence of active regions consisting of cool spots. The other six stars show the opposite behaviour, i.e. they become bluer when they become fainter. For V711 Tau this behaviour could be explained by the increased relative U- and B-flux contribution by the earlier-type component of the binary system when the cooler component becomes fainter. On the other hand, for AR Psc, UX Ari, RS CVn, SZ Psc and AR Lac the existence of hot photospheric faculae must be invoked. We also found that in single-lined and double-lined binary stars in which the fainter component is inactive or much less active the V magnitude is correlated to B-V and U-B color variations in more than 60% of observation seasons. The correlation

  3. Alternative Mating Tactics in Male Chameleons (Chamaeleo chamaeleon Are Evident in Both Long-Term Body Color and Short-Term Courtship Pattern.

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    Tammy Keren-Rotem

    Full Text Available Alternative mating tactics in males of various taxa are associated with body color, body size, and social status. Chameleons are known for their ability to change body color following immediate environmental or social stimuli. In this study, we examined whether the differential appearance of male common chameleon during the breeding season is indeed an expression of alternative mating tactics. We documented body color of males and used computer vision techniques to classify images of individuals into discrete color patterns associated with seasons, individual characteristics, and social contexts. Our findings revealed no differences in body color and color patterns among males during the non-breeding season. However, during the breeding season males appeared in several color displays, which reflected body size, social status, and behavioral patterns. Furthermore, smaller and younger males resembled the appearance of small females. Consequently, we suggest that long-term color change in males during the breeding season reflects male alternative mating tactics. Upon encounter with a receptive female, males rapidly alter their appearance to that of a specific brief courtship display, which reflects their social status. The females, however, copulated indiscriminately in respect to male color patterns. Thus, we suggest that the differential color patterns displayed by males during the breeding season are largely aimed at inter-male signaling.

  4. Alternative Mating Tactics in Male Chameleons (Chamaeleo chamaeleon) Are Evident in Both Long-Term Body Color and Short-Term Courtship Pattern

    Science.gov (United States)

    Keren-Rotem, Tammy; Levy, Noga; Wolf, Lior; Bouskila, Amos; Geffen, Eli

    2016-01-01

    Alternative mating tactics in males of various taxa are associated with body color, body size, and social status. Chameleons are known for their ability to change body color following immediate environmental or social stimuli. In this study, we examined whether the differential appearance of male common chameleon during the breeding season is indeed an expression of alternative mating tactics. We documented body color of males and used computer vision techniques to classify images of individuals into discrete color patterns associated with seasons, individual characteristics, and social contexts. Our findings revealed no differences in body color and color patterns among males during the non-breeding season. However, during the breeding season males appeared in several color displays, which reflected body size, social status, and behavioral patterns. Furthermore, smaller and younger males resembled the appearance of small females. Consequently, we suggest that long-term color change in males during the breeding season reflects male alternative mating tactics. Upon encounter with a receptive female, males rapidly alter their appearance to that of a specific brief courtship display, which reflects their social status. The females, however, copulated indiscriminately in respect to male color patterns. Thus, we suggest that the differential color patterns displayed by males during the breeding season are largely aimed at inter-male signaling. PMID:27409771

  5. The advertisement call, color patterns and distribution of Ischnocnema izecksohni (Caramaschi and Kisteumacher, 1989 (Anura, Brachycephalidae

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    Pedro P. G. Taucce

    2012-01-01

    Full Text Available Ischnocnema izecksohni inhabits the gallery forests from the Quadrilátero Ferrífero, Southern Espinhaço range, state of Minas Gerais, southeastern Brazil, and it is considered endemic to this region. Its closest related species is I. nasuta according to the original description. We describe the advertisement call of I. izecksohni based on specimens recorded and collected at the municipality of Nova Lima, state of Minas Gerais, distant about 10 km straight line from its type locality. The advertisement call consists of a group of notes emitted sporadically without a regular interval between the calls. Call duration (n = 36 calls in four individuals ranged from 1.03 to 1.85 s (= 1.52 ± 0.21 s and the call rise time from 0.66 to 1.52 s (= 1.16 ± 0.25 s, with 34-57 notes per call (= 47.42 ± 6.03. Peak frequency ranged from 2250 to 2625 Hz, the dominant frequency from 1317.8 to 3128.0 Hz and interval between notes from 22.00 to 41.00 ms (= 28.63 ± 0.03 ms. From the examination of herpetological collections, morphological and bioacoustical data we extended the species known distribution ca. 200 km eastward, to ten new localities, all of them outside the Quadrilátero Ferrífero region, at the Mantiqueira mountain range. We analyzed color patterns and we find some dorsal patterns not described at the original description of I. izecksohni. We also make some comments concerning the taxonomic status of I. izecksohni and I. nasuta.

  6. Morpho morphometrics: Shared ancestry and selection drive the evolution of wing size and shape in Morpho butterflies.

    Science.gov (United States)

    Chazot, Nicolas; Panara, Stephen; Zilbermann, Nicolas; Blandin, Patrick; Le Poul, Yann; Cornette, Raphaël; Elias, Marianne; Debat, Vincent

    2016-01-01

    Butterfly wings harbor highly diverse phenotypes and are involved in many functions. Wing size and shape result from interactions between adaptive processes, phylogenetic history, and developmental constraints, which are complex to disentangle. Here, we focus on the genus Morpho (Nymphalidae: Satyrinae, 30 species), which presents a high diversity of sizes, shapes, and color patterns. First, we generate a comprehensive molecular phylogeny of these 30 species. Next, using 911 collection specimens, we quantify the variation of wing size and shape across species, to assess the importance of shared ancestry, microhabitat use, and sexual selection in the evolution of the wings. While accounting for phylogenetic and allometric effects, we detect a significant difference in wing shape but not size among microhabitats. Fore and hindwings covary at the individual and species levels, and the covariation differs among microhabitats. However, the microhabitat structure in covariation disappears when phylogenetic relationships are taken into account. Our results demonstrate that microhabitat has driven wing shape evolution, although it has not strongly affected forewing and hindwing integration. We also found that sexual dimorphism of forewing shape and color pattern are coupled, suggesting a common selective force. © 2015 The Author(s). Evolution © 2015 The Society for the Study of Evolution.

  7. Mining Co-location Pattern of Network Spatial Phenomenon Based on the Law of Additive Color Mixing

    Directory of Open Access Journals (Sweden)

    AI Tinghua

    2017-06-01

    Full Text Available Mining co-location pattern is one of the hottest topics of current research in the spatial data mining community. The existing co-location mining methods belong to spatial statistics or data mining approaches, requiring much understanding of complex mathematical or statistical algorithms and parameters; and they consider events as taking place in a homogeneous and isotropic context in Euclidean space, whereas the physical movement in an urban space is usually constrained by a road network. This paper proposes a visualization method to mine co-location pattern along networks. The visual language is used to represent mutual influence between two geographic phenomena along networks. Firstly, taking Tobler's first law of geography into consideration, we use a network kernel density estimation method to express distribution pattern of geographic phenomena along networks, and construct a mapping between the distribution pattern of geographic phenomenon and color. Secondly, based on the law of additive color mixing, two colors representing two geographic phenomena are mixed to get cognition of the interaction between the two geographic phenomena. This method makes use of visual thinking, and it is intuitive and can be easily understood.

  8. Dual-modality impairment of implicit learning of letter-strings versus color-patterns in patients with schizophrenia

    OpenAIRE

    Chiu, Ming-Jang; Liu, Kristina; Hsieh, Ming H; Hwu, Hai-Gwo

    2005-01-01

    Abstract Background Implicit learning was reported to be intact in schizophrenia using artificial grammar learning. However, emerging evidence indicates that artificial grammar learning is not a unitary process. The authors used dual coding stimuli and schizophrenia clinical symptom dimensions to re-evaluate the effect of schizophrenia on various components of artificial grammar learning. Methods Letter string and color pattern artificial grammar learning performances were compared between 63...

  9. Relationship between tail color pattern and reproductive success, mate acquisition and nest predation in Rufous Bush Chats

    OpenAIRE

    Álvarez, Fernando

    2000-01-01

    Rufous Bush Chats (Cercotrichas galactotes) show a conspicuous tail color pattern consisting of terminal white and subterminal black patches which are shown in tail display during nest defense, aggression, and courtship. Multiple linear regression of visual tail features of males showed that in the two years of study, birds with higher bilateral symmetry in the black patches attained higher seasonal reproductive success, mated earlier in the season, and their nests were less likely to be depr...

  10. Patterns of color phase indicate spawn timing at a Nassau grouper Epinephelus striatus spawning aggregation

    Directory of Open Access Journals (Sweden)

    Stephanie K ARCHER, Scott A HEPPELL, Brice X SEMMENS,Christy V PATTENGILL-SEMMENS, Phillippe G BUSH, Croy M MCCOY,Bradley C JOHNSON

    2012-02-01

    Full Text Available Nassau grouper Epinephelus striatus are a large bodied, top level predator that is ecologically important throughout the Caribbean. Although typically solitary, Nassau grouper form large annual spawning aggregations at predictable times in specific locations. In 2003, The Cayman Islands Marine Conservation Board established protection for a newly rediscovered Nassau grouper spawning aggregation on Little Cayman, British West Indies. The large size of this aggregation provides a unique opportunity to study the behavior of Nassau grouper on a relatively intact spawning aggregation. During non-spawning periods Nassau grouper display a reddish-brown-and-white barred coloration. However, while aggregating they exhibit three additional color phases: “bicolor”, “dark”, and “white belly”. We video sampled the population on multiple days leading up to spawning across five spawning years. Divers focused a laser caliper equipped video camera on individual fish at the aggregation. We later analyzed the video to determine the length of the fish and record the color phase. Our observations show that the relative proportion of fish in the bicolor color phase increases significantly on the day leading up to the primary night of spawning. The increase in the proportion of the bicolor color phase from 0.05 early in the aggregation to 0.40 on the day of spawning suggests that this color phase conveys that a fish is behaviorally and physiologically prepared to spawn. Additionally, 82.7% of fish exhibiting dark or white belly coloration early in the aggregation period suggests that these color phases are not only shown by female fish as was previously posited [Current Zoology 58 (1: 73–83, 2012].

  11. 3D-shape of objects with straight line-motion by simultaneous projection of color coded patterns

    Science.gov (United States)

    Flores, Jorge L.; Ayubi, Gaston A.; Di Martino, J. Matías; Castillo, Oscar E.; Ferrari, Jose A.

    2018-05-01

    In this work, we propose a novel technique to retrieve the 3D shape of dynamic objects by the simultaneous projection of a fringe pattern and a homogeneous light pattern which are both coded in two of the color channels of a RGB image. The fringe pattern, red channel, is used to retrieve the phase by phase-shift algorithms with arbitrary phase-step, while the homogeneous pattern, blue channel, is used to match pixels from the test object in consecutive images, which are acquired at different positions, and thus, to determine the speed of the object. The proposed method successfully overcomes the standard requirement of projecting fringes of two different frequencies; one frequency to extract object information and the other one to retrieve the phase. Validation experiments are presented.

  12. Butterfly Wings Are Three-Dimensional: Pupal Cuticle Focal Spots and Their Associated Structures in Junonia Butterflies.

    Science.gov (United States)

    Taira, Wataru; Otaki, Joji M

    2016-01-01

    Butterfly wing color patterns often contain eyespots, which are developmentally determined at the late larval and early pupal stages by organizing activities of focal cells that can later form eyespot foci. In the pupal stage, the focal position of a future eyespot is often marked by a focal spot, one of the pupal cuticle spots, on the pupal surface. Here, we examined the possible relationships of the pupal focal spots with the underneath pupal wing tissues and with the adult wing eyespots using Junonia butterflies. Large pupal focal spots were found in two species with large adult eyespots, J. orithya and J. almana, whereas only small pupal focal spots were found in a species with small adult eyespots, J. hedonia. The size of five pupal focal spots on a single wing was correlated with the size of the corresponding adult eyespots in J. orithya. A pupal focal spot was a three-dimensional bulge of cuticle surface, and the underside of the major pupal focal spot exhibited a hollowed cuticle in a pupal case. Cross sections of a pupal wing revealed that the cuticle layer shows a curvature at a focal spot, and a positional correlation was observed between the cuticle layer thickness and its corresponding cell layer thickness. Adult major eyespots of J. orithya and J. almana exhibited surface elevations and depressions that approximately correspond to the coloration within an eyespot. Our results suggest that a pupal focal spot is produced by the organizing activity of focal cells underneath the focal spot. Probably because the focal cell layer immediately underneath a focal spot is thicker than that of its surrounding areas, eyespots of adult butterfly wings are three-dimensionally constructed. The color-height relationship in adult eyespots might have an implication in the developmental signaling for determining the eyespot color patterns.

  13. Experimental study on blood flow patterns through the phantoms of the intracranial arterial aneurysms using color Doppler imaging

    International Nuclear Information System (INIS)

    Chung, Tae Sub; Jeong, Eun Kee; Rhim, Yoon Chul; Kim, Sung Bin; Lee, Dong Hoon; Kim, Dae In

    1994-01-01

    The occurrence, growth, thrombosis, and rupture of intracranial saccular aneurysms can be directly related to the effect of hemodynamic forces. We developed the phantom flow models and compared with the computer simulation program to analyse the flow pattern and hemodynamics that might be responsible for the intracranial arterial aneurysms. We designed the arterial phantoms of three major sites of intracranial arterial aneurysm ; 1) basilar artery tip, 2) internal carotid artery bifurcation, 3) curved area of internal carotid artery. Flow patterns in the aneurysmal portion of phantoms were evaluated with color Doppler system on the connection with automatic closed type of circulation system. Then, we compared the results with computer simulation. The hemodynamic characteristics of the phantoms were identical with those obtained by computerisation's. Three distinct zones of flow were identified by color Doppler studies on the aneurysm of the curved area of an internal carotid artery : 1) an inflow zone entering the aneurysm at the distal aspect of its orifice, 2) an outflow zone exiting the aneurysm at the proximal aspect of its orifice, 3) a central slow vortex.However, the phantoms of basilar artery tip and artery bifurcation showed a direct inflow stream at the dome of an aneurysm. Flow dynamics in the various phantoms of the aneurysms can be successfully evaluated with color Doppler imaging, and were consistent with those predicted by computer simulations

  14. Artificial insect wings of diverse morphology for flapping-wing micro air vehicles

    International Nuclear Information System (INIS)

    Shang, J K; Finio, B M; Wood, R J; Combes, S A

    2009-01-01

    The development of flapping-wing micro air vehicles (MAVs) demands a systematic exploration of the available design space to identify ways in which the unsteady mechanisms governing flapping-wing flight can best be utilized for producing optimal thrust or maneuverability. Mimicking the wing kinematics of biological flight requires examining the potential effects of wing morphology on flight performance, as wings may be specially adapted for flapping flight. For example, insect wings passively deform during flight, leading to instantaneous and potentially unpredictable changes in aerodynamic behavior. Previous studies have postulated various explanations for insect wing complexity, but there lacks a systematic approach for experimentally examining the functional significance of components of wing morphology, and for determining whether or not natural design principles can or should be used for MAVs. In this work, a novel fabrication process to create centimeter-scale wings of great complexity is introduced; via this process, a wing can be fabricated with a large range of desired mechanical and geometric characteristics. We demonstrate the versatility of the process through the creation of planar, insect-like wings with biomimetic venation patterns that approximate the mechanical properties of their natural counterparts under static loads. This process will provide a platform for studies investigating the effects of wing morphology on flight dynamics, which may lead to the design of highly maneuverable and efficient MAVs and insight into the functional morphology of natural wings.

  15. Phage-Based Structural Color Sensors and Their Pattern Recognition Sensing System.

    Science.gov (United States)

    Lee, Ju Hun; Fan, Benson; Samdin, Tuan D; Monteiro, David A; Desai, Malav S; Scheideler, Olivia; Jin, Hyo-Eon; Kim, Soyoun; Lee, Seung-Wuk

    2017-04-25

    The mammalian olfactory system provides great inspiration for the design of intelligent sensors. To this end, we have developed a bioinspired phage nanostructure-based color sensor array and a smartphone-based sensing network system. Using a M13 bacteriophage (phage) as a basic building block, we created structural color matrices that are composed of liquid-crystalline bundled nanofibers from self-assembled phages. The phages were engineered to express cross-responsive receptors on their major coat protein (pVIII), leading to rapid, detectable color changes upon exposure to various target chemicals, resulting in chemical- and concentration-dependent color fingerprints. Using these sensors, we have successfully detected 5-90% relative humidity with 0.2% sensitivity. In addition, after modification with aromatic receptors, we were able to distinguish between various structurally similar toxic chemicals including benzene, toluene, xylene, and aniline. Furthermore, we have developed a method of interpreting and disseminating results from these sensors using smartphones to establish a wireless system. Our phage-based sensor system has the potential to be very useful in improving national security and monitoring the environment and human health.

  16. Prey from the eyes of predators: Color discriminability of aposematic and mimetic butterflies from an avian visual perspective.

    Science.gov (United States)

    Su, Shiyu; Lim, Matthew; Kunte, Krushnamegh

    2015-11-01

    Predation exerts strong selection on mimetic butterfly wing color patterns, which also serve other functions such as sexual selection. Therefore, specific selection pressures may affect the sexes and signal components differentially. We tested three predictions about the evolution of mimetic resemblance by comparing wing coloration of aposematic butterflies and their Batesian mimics: (a) females gain greater mimetic advantage than males and therefore are better mimics, (b) due to intersexual genetic correlations, sexually monomorphic mimics are better mimics than female-limited mimics, and (c) mimetic resemblance is better on the dorsal wing surface that is visible to predators in flight. Using a physiological model of avian color vision, we quantified mimetic resemblance from predators' perspective, which showed that female butterflies were better mimics than males. Mimetic resemblance in female-limited mimics was comparable to that in sexually monomorphic mimics, suggesting that intersexual genetic correlations did not constrain adaptive response to selection for female-limited mimicry. Mimetic resemblance on the ventral wing surface was better than that on the dorsal wing surface, implying stronger natural and sexual selection on ventral and dorsal surfaces, respectively. These results suggest that mimetic resemblance in butterfly mimicry rings has evolved under various selective pressures acting in a sex- and wing surface-specific manner. © 2015 The Author(s). Evolution © 2015 The Society for the Study of Evolution.

  17. Caterpillar color patterns are determined by a two-phase melanin gene prepatterning process: new evidence from tan and laccase2.

    Science.gov (United States)

    Futahashi, Ryo; Banno, Yutaka; Fujiwara, Haruhiko

    2010-01-01

    The larval color patterns in Lepidoptera exhibit splendid diversity, and identifying the genes responsible for pigment distribution is essential to understanding color-pattern evolution. The swallowtail butterfly, Papilio xuthus, is a good candidate for analyzing marking-associated genes because its body markings change dramatically at the final molt. Moreover, the silkworm Bombyx mori is most suitable for identification of lab-generated color mutants because genome information and many color mutants are available. Here, we analyzed the expression pattern of 10 melanin-related genes in P. xuthus, and analyzed whether these genes were responsible for Bombyx larval color mutants. We found that seven genes correlated strongly with the stage-specific larval cuticular markings of P. xuthus, suggesting that, compared with Drosophila, more genes showed marking specificity in lepidopteran larvae. We newly found that the expression of both tan and laccase2 is strongly correlated with the larval black markings in both P. xuthus and B. mori. The results of F2 linkage analysis and mutant analysis strongly suggest that tan is the responsible gene for Bombyx larval color mutant rouge, and that tan is important in emphasizing black markings of lepidopteran larvae. Detailed comparison of temporal and spatial expression patterns showed that larval cuticular markings were regulated at two different phases. Marking-specific expression of oxidizing enzymes preceded the marking-specific expression of melanin synthesis enzymes at mRNA level, which is the reverse of the melanin synthesis step.

  18. Is race erased? Decoding race from patterns of neural activity when skin color is not diagnostic of group boundaries.

    Science.gov (United States)

    Ratner, Kyle G; Kaul, Christian; Van Bavel, Jay J

    2013-10-01

    Several theories suggest that people do not represent race when it does not signify group boundaries. However, race is often associated with visually salient differences in skin tone and facial features. In this study, we investigated whether race could be decoded from distributed patterns of neural activity in the fusiform gyri and early visual cortex when visual features that often covary with race were orthogonal to group membership. To this end, we used multivariate pattern analysis to examine an fMRI dataset that was collected while participants assigned to mixed-race groups categorized own-race and other-race faces as belonging to their newly assigned group. Whereas conventional univariate analyses provided no evidence of race-based responses in the fusiform gyri or early visual cortex, multivariate pattern analysis suggested that race was represented within these regions. Moreover, race was represented in the fusiform gyri to a greater extent than early visual cortex, suggesting that the fusiform gyri results do not merely reflect low-level perceptual information (e.g. color, contrast) from early visual cortex. These findings indicate that patterns of activation within specific regions of the visual cortex may represent race even when overall activation in these regions is not driven by racial information.

  19. Veins improve fracture toughness of insect wings.

    Directory of Open Access Journals (Sweden)

    Jan-Henning Dirks

    Full Text Available During the lifetime of a flying insect, its wings are subjected to mechanical forces and deformations for millions of cycles. Defects in the micrometre thin membranes or veins may reduce the insect's flight performance. How do insects prevent crack related material failure in their wings and what role does the characteristic vein pattern play? Fracture toughness is a parameter, which characterises a material's resistance to crack propagation. Our results show that, compared to other body parts, the hind wing membrane of the migratory locust S. gregaria itself is not exceptionally tough (1.04±0.25 MPa√m. However, the cross veins increase the wing's toughness by 50% by acting as barriers to crack propagation. Using fracture mechanics, we show that the morphological spacing of most wing veins matches the critical crack length of the material (1132 µm. This finding directly demonstrates how the biomechanical properties and the morphology of locust wings are functionally correlated in locusts, providing a mechanically 'optimal' solution with high toughness and low weight. The vein pattern found in insect wings thus might inspire the design of more durable and lightweight artificial 'venous' wings for micro-air-vehicles. Using the vein spacing as indicator, our approach might also provide a basis to estimate the wing properties of endangered or extinct insect species.

  20. FijiWingsPolarity: An open source toolkit for semi-automated detection of cell polarity.

    Science.gov (United States)

    Dobens, Leonard L; Shipman, Anna; Axelrod, Jeffrey D

    2017-12-22

    Epithelial cells are defined by apical-basal and planar cell polarity (PCP) signaling, the latter of which establishes an orthogonal plane of polarity in the epithelial sheet. PCP signaling is required for normal cell migration, differentiation, stem cell generation and tissue repair, and defects in PCP have been associated with developmental abnormalities, neuropathologies and cancers. While the molecular mechanism of PCP is incompletely understood, the deepest insights have come from Drosophila, where PCP is manifest in hairs and bristles across the adult cuticle and organization of the ommatidia in the eye. Fly wing cells are marked by actin-rich trichome structures produced at the distal edge of each cell in the developing wing epithelium and in a mature wing the trichomes orient collectively in the distal direction. Genetic screens have identified key PCP signaling pathway components that disrupt trichome orientation, which has been measured manually in a tedious and error prone process. Here we describe a set of image processing and pattern-recognition macros that can quantify trichome arrangements in micrographs and mark these directly by color, arrow or colored arrow to indicate trichome location, length and orientation. Nearest neighbor calculations are made to exploit local differences in orientation to better and more reliably detect and highlight local defects in trichome polarity. We demonstrate the use of these tools on trichomes in adult wing preps and on actin-rich developing trichomes in pupal wing epithelia stained with phalloidin. FijiWingsPolarity is freely available and will be of interest to a broad community of fly geneticists studying the effect of gene function on PCP.

  1. Early Birds by Light at Night: Effects of Light Color and Intensity on Daily Activity Patterns in Blue Tits.

    Science.gov (United States)

    de Jong, Maaike; Caro, Samuel P; Gienapp, Phillip; Spoelstra, Kamiel; Visser, Marcel E

    2017-08-01

    Artificial light at night disturbs the daily rhythms of many organisms. To what extent this disturbance depends on the intensity and spectral composition of light remain obscure. Here, we measured daily activity patterns of captive blue tits ( Cyanistes caeruleus) exposed to similar intensities of green, red, or white light at night. Birds advanced their onset of activity in the morning under all light colors but more under red and white light than under green light. Offset of activity was slightly delayed in all light colors. The total activity over a 24-h period did not change but birds moved a part of their daily activity into the night. Since the effect of red and white lights are comparable, we tested the influence of light intensity in a follow-up experiment, where we compared the activity of the birds under different intensities of green and white light only. While in the higher range of intensities, the effects of white and green light were comparable; at lower intensities, green light had a less disturbing effect as compared with white light on daily rhythms in blue tits. Our results show that the extent of this disturbance can be mitigated by modulating the spectral characteristics and intensity of outdoor lighting, which is now feasible through the use of LED lighting.

  2. FijiWings: an open source toolkit for semiautomated morphometric analysis of insect wings.

    Science.gov (United States)

    Dobens, Alexander C; Dobens, Leonard L

    2013-08-07

    Development requires coordination between cell proliferation and cell growth to pattern the proper size of tissues, organs, and whole organisms. The Drosophila wing has landmark features, such as the location of veins patterned by cell groups and trichome structures produced by individual cells, that are useful to examine the genetic contributions to both tissue and cell size. Wing size and trichome density have been measured manually, which is tedious and error prone, and although image processing and pattern-recognition software can quantify features in micrographs, this approach has not been applied to insect wings. Here we present FijiWings, a set of macros designed to perform semiautomated morphophometric analysis of a wing photomicrograph. FijiWings uses plug-ins installed in the Fiji version of ImageJ to detect and count trichomes and measure wing area either to calculate trichome density of a defined region selected by the user or generate a heat map of overall trichome densities. For high-throughput screens we have developed a macro that directs a trainable segmentation plug-in to detect wing vein locations either to measure trichome density in specific intervein regions or produce a heat map of relative intervein areas. We use wing GAL4 drivers and UAS-regulated transgenes to confirm the ability of these tools to detect changes in overall tissue growth and individual cell size. FijiWings is freely available and will be of interest to a broad community of fly geneticists studying both the effect of gene function on wing patterning and the evolution of wing morphology.

  3. Dual-modality impairment of implicit learning of letter-strings versus color-patterns in patients with schizophrenia

    Directory of Open Access Journals (Sweden)

    Hwu Hai-Gwo

    2005-12-01

    Full Text Available Abstract Background Implicit learning was reported to be intact in schizophrenia using artificial grammar learning. However, emerging evidence indicates that artificial grammar learning is not a unitary process. The authors used dual coding stimuli and schizophrenia clinical symptom dimensions to re-evaluate the effect of schizophrenia on various components of artificial grammar learning. Methods Letter string and color pattern artificial grammar learning performances were compared between 63 schizophrenic patients and 27 comparison subjects. Four symptom dimensions derived from a Chinese Positive and Negative Symptom Scale ratings were correlated with patients' artificial grammar implicit learning performances along the two stimulus dimensions. Patients' explicit memory performances were assessed by verbal paired associates and visual reproduction subtests of the Wechsler Memory Scales Revised Version to provide a contrast to their implicit memory function. Results Schizophrenia severely hindered color pattern artificial grammar learning while the disease affected lexical string artificial grammar learning to a lesser degree after correcting the influences from age, education and the performance of explicit memory function of both verbal and visual modalities. Both learning performances correlated significantly with the severity of patients' schizophrenic clinical symptom dimensions that reflect poor abstract thinking, disorganized thinking, and stereotyped thinking. Conclusion The results of this study suggested that schizophrenia affects various mechanisms of artificial grammar learning differently. Implicit learning, knowledge acquisition in the absence of conscious awareness, is not entirely intact in patients with schizophrenia. Schizophrenia affects implicit learning through an impairment of the ability of making abstractions from rules and at least in part decreasing the capacity for perceptual learning.

  4. Veins Improve Fracture Toughness of Insect Wings

    Science.gov (United States)

    Dirks, Jan-Henning; Taylor, David

    2012-01-01

    During the lifetime of a flying insect, its wings are subjected to mechanical forces and deformations for millions of cycles. Defects in the micrometre thin membranes or veins may reduce the insect’s flight performance. How do insects prevent crack related material failure in their wings and what role does the characteristic vein pattern play? Fracture toughness is a parameter, which characterises a material’s resistance to crack propagation. Our results show that, compared to other body parts, the hind wing membrane of the migratory locust S. gregaria itself is not exceptionally tough (1.04±0.25 MPa√m). However, the cross veins increase the wing’s toughness by 50% by acting as barriers to crack propagation. Using fracture mechanics, we show that the morphological spacing of most wing veins matches the critical crack length of the material (1132 µm). This finding directly demonstrates how the biomechanical properties and the morphology of locust wings are functionally correlated in locusts, providing a mechanically ‘optimal’ solution with high toughness and low weight. The vein pattern found in insect wings thus might inspire the design of more durable and lightweight artificial ‘venous’ wings for micro-air-vehicles. Using the vein spacing as indicator, our approach might also provide a basis to estimate the wing properties of endangered or extinct insect species. PMID:22927966

  5. A key, based on wing patterns of biting midges (genus Culicoides Latreille - Diptera: Ceratopogonidae in the Iberian Peninsula, for use in epidemiological studies

    Directory of Open Access Journals (Sweden)

    Rawlings, Peter

    1996-12-01

    Full Text Available The identity of vectors of disease are often required speedily in epidemiological studies but with a precision which excludes as many other species as possible. Identification keys usually require the examination of many different parts of the suspected vector to pinpoint the species. This consumes considerable time and resources, so epidemiologists tend to ignore them. Asimplified approach to identification is proposed, using the characteristics of a single part of the body (the wings of biting midges of the genus Culicoides. The level of differentiation was epidemiologically valuable. The monoclave could not differentiate all the species from each other but more than one third (20/58 of identifications were for single species, and a further 12/58 identifications gave only two possibilities, making 55.2% of identifications to an accuracy of at most one of two species. The diagnosis of vector species was reached in a maximum of six decision points. The only notable exception to valuable differentiation was the four species in the Culicoides obsoletus group which had almost identical female wing patterns. The ready availability of simple keys, which can be used by anyone without formal training in taxonomy, for all the species of a group in a region should encourage greater standardisation of identifications in all studies, including those not primarily aimed at systematics. These monoclaves can also serve as the primary tools to build computerised image-recognition systems for genera, families and orders of insects.Con frequencia en los estudios epidemiológicos hace falta conocer con rapidez, pero también con precisión, la identidad de los vectores. Por lo general los procedimientos de identificación y las claves exigen el examen de un elevado número de partes diferentes del vector sospechoso. Este enfoque consume mucho tiempo y recursos por lo que tiende a ser evitado por los epidemiólogos. Se propone un sistema simplificado para la

  6. Color vision versus pattern visual evoked potentials in the assessment of subclinical optic pathway involvement in multiple sclerosis

    Directory of Open Access Journals (Sweden)

    Fatih C Gundogan

    2013-01-01

    Full Text Available Background: Optic pathway involvement in multiple sclerosis is frequently the initial sign in the disease process. In most clinical applications, pattern visual evoked potential (PVEP is used in the assessment of optic pathway involvement. Objective: To question the value of PVEP against color vision assessment in the diagnosis of subclinical optic pathway involvement. Materials and Methods: This prospective, cross-sectional study included 20 multiple sclerosis patients without a history of optic neuritis, and 20 healthy control subjects. Farnsworth-Munsell (FM 100-Hue testing and PVEPs to 60-min arc and 15-min arc checks by using Roland-Consult RetiScan® system were performed. P 100 amplitude, P 100 latency in PVEP and total error scores (TES in FM 100-Hue test were assessed. Results: Expanded Disability Status Scale score and the time from diagnosis were 2.21 ± 2.53 (ranging from 0 to 7 and 4.1 ± 4.4 years. MS group showed significantly delayed P 100 latency for both checks (P 0.05 for all. 14 MS patients (70% had an increased TESs in FM-100 Hue, 11 (55% MS patients had delayed P 100 latency and 9 (45% had reduced P 100 amplitude. The areas under the ROC curves were 0.944 for FM-100 Hue test, 0.753 for P 100 latency, and 0.173 for P 100 amplitude. Conclusions: Color vision testing seems to be more sensitive than PVEP in detecting subclinical visual pathway involvement in MS.

  7. The Petrolisthes galathinus complex: species boundaries based on color pattern, morphology and molecules, and evolutionary interrelationships between this complex and other Porcellanidae (Crustacea: Decapoda: Anomura).

    Science.gov (United States)

    Hiller, Alexandra; Kraus, Holger; Almon, Marc; Werding, Bernd

    2006-08-01

    While the amphi-American porcellanid crab Petrolistes galathinus has been traditionally viewed as a highly variable species containing several different color forms, we consider it to be a complex of at least 6 morphologically similar species with similar ecological requirements, but diagnosable through coloration. Here we surveyed sequence variation of the mitochondrial 16S rRNA gene, compared the morphology of adults and of the first larval stage (Zoea I), and explored shape variation of the sternal plate using geometric morphometric methods, to investigate boundaries among the species in the complex, and to confirm the validity of color and color pattern for distinguishing them. Sequences and larval morphological characters of other porcellanids were included to investigate the correspondence between genetic divergence and morphology of adults and larvae. The molecular and morphometric results support the validity of the species in the complex, and of color pattern for their distinction. The close relationship between the complex and the putative ancenstral porcellanid Parapetrolisthes tortugensis was indicated by the molecular and larval-morphology results. The adult morphology of this species is interpreted as a result of convergent evolution driven by a relatively rapid ecological adaptation to conditions in deeper waters. The nesting position in the phylogenetic trees of Petrocheles australiensis outside the Porcellanidae clade questions the monophyly of this family.

  8. The developmental pattern of stimulus and response interference in a color-object Stroop task: an ERP study

    Directory of Open Access Journals (Sweden)

    Jongen Ellen MM

    2008-09-01

    Full Text Available Abstract Background Several studies have shown that Stroop interference is stronger in children than in adults. However, in a standard Stroop paradigm, stimulus interference and response interference are confounded. The purpose of the present study was to determine whether interference at the stimulus level and the response level are subject to distinct maturational patterns across childhood. Three groups of children (6–7 year-olds, 8–9 year-olds, and 10–12 year-olds and a group of adults performed a manual Color-Object Stroop designed to disentangle stimulus interference and response interference. This was accomplished by comparing three trial types. In congruent (C trials there was no interference. In stimulus incongruent (SI trials there was only stimulus interference. In response incongruent (RI trials there was stimulus interference and response interference. Stimulus interference and response interference were measured by a comparison of SI with C, and RI with SI trials, respectively. Event-related potentials (ERPs were measured to study the temporal dynamics of these processes of interference. Results There was no behavioral evidence for stimulus interference in any of the groups, but in 6–7 year-old children ERPs in the SI condition in comparison with the C condition showed an occipital P1-reduction (80–140 ms and a widely distributed amplitude enhancement of a negative component followed by an amplitude reduction of a positive component (400–560 ms. For response interference, all groups showed a comparable reaction time (RT delay, but children made more errors than adults. ERPs in the RI condition in comparison with the SI condition showed an amplitude reduction of a positive component over lateral parietal (-occipital sites in 10–12 year-olds and adults (300–540 ms, and a widely distributed amplitude enhancement of a positive component in all age groups (680–960 ms. The size of the enhancement correlated positively

  9. Study of nano-architecture of the wings of Paris Peacock butterfly

    Science.gov (United States)

    Ghate, Ekata; Bhoraskar, S. V.; Kulkarni, G. R.

    Butterflies are one of the most colorful creatures in animal Kingdom. Wings of the male butterfly are brilliantly colored to attract females. Color of the wings plays an important role in camouflage. Study of structural colors in case of insects and butterflies are important for their biomimic and biophotonic applications. Structural color is the color which is produced by physical structures and their interaction with light. Paris Peacock or Papilio paris butterfly belongs to the family Papilionidae. The basis of structural color of this butterfly is investigated in the present study. The upper surface of the wings in this butterfly is covered with blue, green and brown colored scales. Nano-architecture of these scales was investigated with scanning electron microscope (SEM) and environmental scanning electron microscope (ESEM). Photomicrographs were analyzed using image analysis software. Goniometric color or iridescence in blue and green colored scales of this butterfly was observed and studied with the help of gonio spectrophotometer in the visible range. No iridescence was observed in brown colored scales of the butterfly. Hues of the blue and green color were measured with spectrophotometer and were correlated with nano-architecture of the wing. Results of electron microscopy and reflection spectroscopy are used to explain the iridescent nature of blue and green scales. Sinusoidal grating like structures of these scales were prominently seen in the blue scales. It is possible that the structure of these wings can act as a template for the fabrication of sinusoidal gratings using nano-imprint technology.

  10. Color-induced graph colorings

    CERN Document Server

    Zhang, Ping

    2015-01-01

    A comprehensive treatment of color-induced graph colorings is presented in this book, emphasizing vertex colorings induced by edge colorings. The coloring concepts described in this book depend not only on the property required of the initial edge coloring and the kind of objects serving as colors, but also on the property demanded of the vertex coloring produced. For each edge coloring introduced, background for the concept is provided, followed by a presentation of results and open questions dealing with this topic. While the edge colorings discussed can be either proper or unrestricted, the resulting vertex colorings are either proper colorings or rainbow colorings. This gives rise to a discussion of irregular colorings, strong colorings, modular colorings, edge-graceful colorings, twin edge colorings and binomial colorings. Since many of the concepts described in this book are relatively recent, the audience for this book is primarily mathematicians interested in learning some new areas of graph colorings...

  11. Reflection characterization of nano-sized dielectric structure in Morpho butterfly wings

    Science.gov (United States)

    Zhu, Dong

    2017-10-01

    Morpho butterflies living in Central and South America are well-known for their structural-colored blue wings. The blue coloring originates from the interaction of light with nano-sized dielectric structures that are equipped on the external surface of scales covering over their wings. The high-accuracy nonstandard finite-difference time domain (NS-FDTD) method is used to investigate the reflection characterization from the nanostructures. In the NS-FDTD calculation, a computational model is built to mimic the actual tree-like multilayered structures wherever possible using the hyperbolic tangent functions. It is generally known that both multilayer interference and diffraction grating phenomena can occur when light enters the nano-sized multilayered structure. To answer the question that which phenomenon is mainly responsible for the blue coloring, the NS-FDTD calculation is performed under various incidence angles at wavelengths from 360 to 500 nm. The calculated results at one incident wavelength under different incidence angles are visualized in a two-dimensional mapping image, where horizontal and vertical axes are incidence and reflection angles, respectively. The images demonstrate a remarkable transition from a ring-like pattern at shorter wavelengths to a retro-reflection pattern at longer wavelengths. To clarify the origin of the pattern transition, the model is separated into several simpler parts and compared their mapping images with the theoretical diffraction calculations. It can be concluded that the blue coloring at longer wavelengths is mainly caused by the cooperation of multilayer interference and retro-reflection while the effect of diffraction grating is predominant at shorter wavelengths.

  12. Structural color films with lotus effects, superhydrophilicity, and tunable stop-bands.

    Science.gov (United States)

    Sato, Osamu; Kubo, Shoichi; Gu, Zhong-Ze

    2009-01-20

    The structural blue color of a Morpho butterfly originates from the diffraction of light and interference effects due to the presence of the microstructures on the wing of the butterfly. Structural color on the surface of a damselfish reversibly changes between green and blue. Inspired by these creatures, we have been trying to prepare high-quality and functional structural color films. We describe our efforts in this Account. A useful technique to prepare such structural color films in colloidal solution is a "lifting" method, which allows us to quickly fabricate brilliant colloidal crystal films. The thicknesses of the films can be controlled by precisely adjusting the particle concentration and the lifting speed. Moreover, in order to prepare a complicated structure, we have used template methods. Indeed, we have successfully prepared the inverse structure of the wing of a Morpho butterfly with this technique. Initially, however, our structural color films had a whitish appearance due to the scattering of light by defects in the colloidal crystal film. Later, we were able to prepare a non-whitish structural color film by doping an appropriate dye in the colloidal particles to absorb the scattering light. In addition to the structural blue color, the wing of the Morpho butterfly has superhydrophobic properties. According to Wenzel's equation, the hydrophobic and hydrophilic properties are enhanced when the roughness of the hydrophobic and hydrophilic surface is increased, respectively. Based on this mechanism, we have successfully prepared structural color films with superhydrophobic properties, as well as with superhydrophilic properties. Another important property that can be seen in nature is tunable structural color, such as the color change that can be seen on the surface of a damselfish. In order to mimic such color change, we have developed several tunable structural color films. In particular, we have successfully prepared phototunable photonic crystals

  13. A Single-Wing Removal Method to Assess Correspondence Between Gene Expression and Phenotype in Butterflies: The Case of Distal-less.

    Science.gov (United States)

    Adhikari, Kiran; Otaki, Joji M

    2016-02-01

    It is often desirable but difficult to retrieve information on the mature phenotype of an immature tissue sample that has been subjected to gene expression analysis. This problem cannot be ignored when individual variation within a species is large. To circumvent this problem in the butterfly wing system, we developed a new surgical method for removing a single forewing from a pupa using Junonia orithya; the operated pupa was left to develop to an adult without eclosion. The removed right forewing was subjected to gene expression analysis, whereas the non-removed left forewing was examined for color patterns. As a test case, we focused on Distal-less (Dll), which likely plays an active role in inducing elemental patterns, including eyespots. The Dll expression level in forewings was paired with eyespot size data from the same individual. One third of the operated pupae survived and developed wing color patterns. Dll expression levels were significantly higher in males than in females, although male eyespots were smaller in size than female eyespots. Eyespot size data showed weak but significant correlations with the Dll expression level in females. These results demonstrate that a single-wing removal method was successfully applied to the butterfly wing system and suggest the weak and non-exclusive contribution of Dll to eyespot size determination in this butterfly. Our novel methodology for establishing correspondence between gene expression and phenotype can be applied to other candidate genes for color pattern development in butterflies. Conceptually similar methods may also be applicable in other developmental systems.

  14. Modeling color preference using color space metrics.

    Science.gov (United States)

    Schloss, Karen B; Lessard, Laurent; Racey, Chris; Hurlbert, Anya C

    2017-07-27

    Studying color preferences provides a means to discover how perceptual experiences map onto cognitive and affective judgments. A challenge is finding a parsimonious way to describe and predict patterns of color preferences, which are complex with rich individual differences. One approach has been to model color preferences using factors from metric color spaces to establish direct correspondences between dimensions of color and preference. Prior work established that substantial, but not all, variance in color preferences could be captured by weights on color space dimensions using multiple linear regression. The question we address here is whether model fits may be improved by using different color metric specifications. We therefore conducted a large-scale analysis of color space models, and focused in-depth analysis on models that differed in color space (cone-contrast vs. CIELAB), coordinate system within the color space (Cartesian vs. cylindrical), and factor degrees (1st degree only, or 1st and 2nd degree). We used k-fold cross validation to avoid over-fitting the data and to ensure fair comparisons across models. The best model was the 2nd-harmonic Lch model ("LabC Cyl2"). Specified in CIELAB space, it included 1st and 2nd harmonics of hue (capturing opponency in hue preferences and simultaneous liking/disliking of both hues on an opponent axis, respectively), lightness, and chroma. These modeling approaches can be used to characterize and compare patterns for group averages and individuals in future datasets on color preference, or other measures in which correspondences between color appearance and cognitive or affective judgments may exist. Copyright © 2017 Elsevier Ltd. All rights reserved.

  15. Color transparency

    International Nuclear Information System (INIS)

    Miller, G.A.

    1993-01-01

    Imagine shooting a beam of protons of high momentum P through an atomic nucleus. Usually the nuclear interactions prevent the particles from emerging with momentum ∼P. Further, the angular distribution of elastically scattered protons is close to the optical diffraction pattern produced by a black disk. Thus the nucleus acts as a black disk and is not transparent. However, certain high momentum transfer reactions in which a proton is knocked out of the nucleus may be completely different. Suppose that the high momentum transfer process leads to the formation of a small-size color singlet wavepacket that is ejected from the nucleus. The effects of gluons emitted by color singlet systems of closely separated quarks and gluons tend to cancel. Thus the wavepacket-nuclear interactions are suppressed, the nucleus becomes transparant and one says that color transparency CT occurs. The observation of CT also requires that the wavepacket not expand very much while it moves through the nucleus. Simple quantum mechanical formulations can assess this expansion. The creation of a small-sized wavepacket is expected in asymptotic perturbative effects. The author reviews the few experimental attempts to observe color transparency in nuclear (e,e'p) and (p,pp) reactions and interpret the data and their implications

  16. Colorism/Neo-Colorism

    Science.gov (United States)

    Snell, Joel

    2017-01-01

    There are numerous aspects to being non-Caucasian that may not be known by Whites. Persons of color suggest folks who are African, South Americans, Native Americans, Biracial, Asians and others. The question is what do these individuals feel relative to their color and facial characteristics. Eugene Robinson suggest that the future favorable color…

  17. Acral melanocytic lesions in the United States: Prevalence, awareness, and dermoscopic patterns in skin-of-color and non-Hispanic white patients.

    Science.gov (United States)

    Madankumar, Reshmi; Gumaste, Priyanka V; Martires, Kathryn; Schaffer, Panta R; Choudhary, Sonal; Falto-Aizpurua, Leyre; Arora, Harleen; Kallis, Penelope J; Patel, Shailee; Damanpour, Shadi; Sanchez, Margaret I; Yin, Natalie; Chan, Aegean; Sanchez, Miguel; Polsky, David; Kanavy, Holly; Grichnik, James M; Stein, Jennifer A

    2016-04-01

    Acral lentiginous melanoma has increased mortality compared with other melanoma subtypes and disproportionately affects ethnic minorities. Acral melanocytic lesions have not been well studied in diverse populations of the United States. We sought to assess the prevalence, awareness, and dermoscopic patterns of acral melanocytic lesions in skin-of-color and non-Hispanic white patients. We prospectively examined the palms and soles of 1052 patients presenting to dermatology clinics in New York, NY, and Miami, FL, from October 2013 to April 2015. Acral melanocytic lesions were observed in 36% of our cohort. Skin-of-color patients were more likely to have acral melanocytic lesions than non-Hispanic white patients (P white patients. The majority of lesions demonstrated benign dermoscopic patterns. We observed 2 lesions with the parallel ridge pattern in our cohort, both found to be atypical nevi on biopsy specimen. Patients often lacked awareness of the presence of their lesions. Interobserver variability in assessing dermoscopic patterns is a limitation. Melanocytic lesions of the palms and soles are common, particularly in a cohort of multiple ethnicities from the United States. Dermoscopy of acral lesions is an important clinical tool for diagnosis and management of these lesions. Copyright © 2015 American Academy of Dermatology, Inc. Published by Elsevier Inc. All rights reserved.

  18. Flow structure of vortex-wing interaction

    Science.gov (United States)

    McKenna, Christopher K.

    Impingement of a streamwise-oriented vortex upon a fin, tail, blade or wing represents a fundamental class of flow-structure interaction that extends across a range of applications. This interaction can give rise to time-averaged loading, as well as unsteady loading known as buffeting. The loading is sensitive to parameters of the incident vortex as well as the location of vortex impingement on the downstream aerodynamic surface, generically designated as a wing. Particle image velocimetry is employed to determine patterns of velocity, vorticity, swirl ratio, and streamlines on successive cross-flow planes upstream of and along the wing, which lead to volume representations and thereby characterization of the interaction. At locations upstream of the leading edge of the wing, the evolution of the incident vortex is affected by the presence of the wing, and is highly dependent on the spanwise location of vortex impingement. Even at spanwise locations of impingement well outboard of the wing tip, a substantial influence on the structure of the incident vortex at locations significantly upstream of the leading edge of the wing was observed. For spanwise locations close to or intersecting the vortex core, the effects of upstream influence of the wing on the vortex are to: decrease the swirl ratio; increase the streamwise velocity deficit; decrease the streamwise vorticity; increase the azimuthal vorticity; increase the upwash; decrease the downwash; and increase the root-mean-square fluctuations of both streamwise velocity and vorticity. The interrelationship between these effects is addressed, including the rapid attenuation of axial vorticity in presence of an enhanced defect of axial velocity in the central region of the vortex. Moreover, when the incident vortex is aligned with, or inboard of, the tip of the wing, the swirl ratio decreases to values associated with instability of the vortex, giving rise to enhanced values of azimuthal vorticity relative to the

  19. Quantitative Genetic Analyses of Male Color Pattern and Female Mate Choice in a Pair of Cichlid Fishes of Lake Malawi, East Africa.

    Directory of Open Access Journals (Sweden)

    Baoqing Ding

    Full Text Available The traits involved in sexual selection, such as male secondary sexual characteristics and female mate choice, often co-evolve which can promote population differentiation. However, the genetic architecture of these phenotypes can influence their evolvability and thereby affect the divergence of species. The extraordinary diversity of East African cichlid fishes is often attributed to strong sexual selection and thus this system provides an excellent model to test predictions regarding the genetic architecture of sexually selected traits that contribute to reproductive isolation. In particular, theory predicts that rapid speciation is facilitated when male sexual traits and female mating preferences are controlled by a limited number of linked genes. However, few studies have examined the genetic basis of male secondary sexual traits and female mating preferences in cichlids and none have investigated the genetic architecture of both jointly. In this study, we artificially hybridized a pair of behaviorally isolated cichlid fishes from Lake Malawi and quantified both melanistic color pattern and female mate choice. We investigated the genetic architecture of both phenotypes using quantitative genetic analyses. Our results suggest that 1 many non-additively acting genetic factors influence melanistic color patterns, 2 female mate choice may be controlled by a minimum of 1-2 non-additive genetic factors, and 3 F2 female mate choice is not influenced by male courting effort. Furthermore, a joint analysis of color pattern and female mate choice indicates that the genes underlying these two traits are unlikely to be physically linked. These results suggest that reproductive isolation may evolve rapidly owing to the few genetic factors underlying female mate choice. Hence, female mate choice likely played an important role in the unparalleled speciation of East African cichlid fish.

  20. The role of wing kinematics of freely flying birds downstream the wake of flapping wings

    Science.gov (United States)

    Krishnan, Krishnamoorthy; Gurka, Roi

    2016-11-01

    Avian aerodynamics has been a topic of research for centuries. Avian flight features such as flapping, morphing and maneuvering make bird aerodynamics a complex system to study, analyze and understand. Aerodynamic performance of the flapping wings can be quantified by measuring the vortex structures present in the downstream wake. Still, the direct correlation between the flapping wing kinematics and the evolution of wake features need to be established. In this present study, near wake of three bird species (western sandpiper, European starling and American robin) have been measured experimentally. Long duration, time-resolved, particle image velocimetry technique has been used to capture the wake properties. Simultaneously, the bird kinematics have been captured using high speed camera. Wake structures are reconstructed from the collected PIV images for long chord distances downstream. Wake vorticities and circulation are expressed in the wake composites. Comparison of the wake features of the three birds shows similarities and some key differences are also found. Wing tip motions of the birds are extracted for four continuous wing beat cycle to analyze the wing kinematics. Kinematic parameters of all the three birds are compared to each other and similar trends exhibited by all the birds have been observed. A correlation between the wake evolutions with the wing motion is presented. It was found that the wings' motion generates unique flow patterns at the near wake, especially at the transition phases. At these locations, a drastic change in the circulation was observed.

  1. Diffusion barriers for achieving controlled concentrations of luminescent dopants via diffusion for mask-less RGB color patterning of organic light emitting devices.

    Science.gov (United States)

    Kajiyama, Yoshitaka; Kajiyama, Koichi; Aziz, Hany

    2015-11-30

    Using molecular diffusion as an approach to introduce organic luminescent dopants for making organic light emitting devices (OLEDs) of different colors on one substrate has the potential to overcome the yield and resolution limitations of the current OLED display technology. In this work, diffusion barriers made of MoO3 and a hole transport material mixture are introduced. The barriers effectively confine the diffusion of the dopants to only the desired depths. With the use of these barriers, OLEDs with highly controlled doping concentrations and performance are fabricated. The barriers thus allow utilizing simple diffusion methods for RGB patterning in OLEDs.

  2. Sexual dichroism and pigment localization in the wing scales of Pieris rapae butterflies

    NARCIS (Netherlands)

    Giraldo, M. A.; Stavenga, D. G.

    2007-01-01

    The beads in the wing scales of pierid butterflies play a crucially important role in wing coloration as shown by spectrophotometry and scanning electron microscopy (SEM). The beads contain pterin pigments, which in Pieris rapae absorb predominantly in the ultraviolet (UV). SEM demonstrates that in

  3. SWS2 visual pigment evolution as a test of historically contingent patterns of plumage color evolution in warblers.

    Science.gov (United States)

    Bloch, Natasha I; Morrow, James M; Chang, Belinda S W; Price, Trevor D

    2015-02-01

    Distantly related clades that occupy similar environments may differ due to the lasting imprint of their ancestors-historical contingency. The New World warblers (Parulidae) and Old World warblers (Phylloscopidae) are ecologically similar clades that differ strikingly in plumage coloration. We studied genetic and functional evolution of the short-wavelength-sensitive visual pigments (SWS2 and SWS1) to ask if altered color perception could contribute to the plumage color differences between clades. We show SWS2 is short-wavelength shifted in birds that occupy open environments, such as finches, compared to those in closed environments, including warblers. Phylogenetic reconstructions indicate New World warblers were derived from a finch-like form that colonized from the Old World 15-20 Ma. During this process, the SWS2 gene accumulated six substitutions in branches leading to New World warblers, inviting the hypothesis that passage through a finch-like ancestor resulted in SWS2 evolution. In fact, we show spectral tuning remained similar across warblers as well as the finch ancestor. Results reject the hypothesis of historical contingency based on opsin spectral tuning, but point to evolution of other aspects of visual pigment function. Using the approach outlined here, historical contingency becomes a generally testable theory in systems where genotype and phenotype can be connected. © 2014 The Author(s). Evolution © 2014 The Society for the Study of Evolution.

  4. Glowing seashells: diversity of fossilized coloration patterns on coral reef-associated cone snail (Gastropoda: Conidae shells from the Neogene of the Dominican Republic.

    Directory of Open Access Journals (Sweden)

    Jonathan R Hendricks

    Full Text Available The biology of modern Conidae (cone snails--which includes the hyperdiverse genus Conus--has been intensively studied, but the fossil record of the clade remains poorly understood, particularly within an evolutionary framework. Here, ultraviolet light is used to reveal and characterize the original shell coloration patterns of 28 species of cone snails from three Neogene coral reef-associated deposits from the Cibao Valley, northern Dominican Republic. These fossils come from the upper Miocene Cercado Fm. and lower Pliocene Gurabo Fm., and range in age from about 6.6-4.8 Ma. Comparison of the revealed coloration patterns with those of extant species allow the taxa to be assigned to three genera of cone snails (Profundiconus, Conasprella, and Conus and at least nine subgenera. Thirteen members of these phylogenetically diverse reef faunas are described as new species. These include: Profundiconus? hennigi, Conasprella (Ximeniconus ageri, Conus anningae, Conus lyelli, Conus (Atlanticonus? franklinae, Conus (Stephanoconus gouldi, Conus (Stephanoconus bellacoensis, Conus (Ductoconus cashi, Conus (Dauciconus garrisoni, Conus (Dauciconus? zambaensis, Conus (Spuriconus? kaesleri, Conus (Spuriconus? lombardii, and Conus (Lautoconus? carlottae. Each of the three reef deposits contain a minimum of 14-16 cone snail species, levels of diversity that are similar to modern Indo-Pacific reef systems. Finally, most of the 28 species can be assigned to modern clades and thus have important implications for understanding the biogeographic and temporal histories of these clades in tropical America.

  5. Effects of Canard on the Flowfield over a Wing

    Science.gov (United States)

    Nayebzadeh, Arash

    2015-11-01

    Surface and flowfield pressure measurements have been done over delta wing/canard configuration in a variety of canard vertical and horizontal locations and angles of attack. The experimental model consisted of wing, canard and a body to accommodate pressure tubing and canard rotation mechanism. All the tests have been performed at subsonic velocities and the effect of canard were analyzed through comparison between surface and flowfield pressure distributions. It was found that vortex flow pattern over the wing is dominated mainly by canard vertical position and in some cases, by merging of canard and wing vortices. In addition, the pressure loss induced by canard vortex on the wing surface moves the wing vortex toward the leading edge. In the mid canard configuration, canard and wing vortices merge at x/c greater than 0.5 and as a result of this phenomenon, abrupt pressure loss induces more stable vortex flow over the wing. It is also shown that canard plays a vital role in vortex break down over the wing.

  6. Atypical performance patterns on Delis-Kaplan Executive Functioning System Color-Word Interference Test: Cognitive switching and learning ability in older adults.

    Science.gov (United States)

    Berg, Jody-Lynn; Swan, Natasha M; Banks, Sarah J; Miller, Justin B

    2016-09-01

    Cognitive set shifting requires flexible application of lower level processes. The Delis-Kaplan Executive Functioning System (DKEFS) Color-Word Interference Test (CWIT) is commonly used to clinically assess cognitive set shifting. An atypical pattern of performance has been observed on the CWIT; a subset of individuals perform faster, with equal or fewer errors, on the more difficult inhibition/switching than the inhibition trial. This study seeks to explore the cognitive underpinnings of this atypical pattern. It is hypothesized that atypical patterns on CWIT will be associated with better performance on underlying cognitive measures of attention, working memory, and learning when compared to typical CWIT patterns. Records from 239 clinical referrals (age: M = 68.09 years, SD = 10.62; education: M = 14.87 years, SD = 2.73) seen for a neuropsychological evaluation as part of diagnostic work up in an outpatient dementia and movement disorders clinic were sampled. The standard battery of tests included measures of attention, learning, fluency, executive functioning, and working memory. Analyses of variance (ANOVAs) were conducted to compare the cognitive performance of those with typical versus atypical CWIT patterns. An atypical pattern of performance was confirmed in 23% of our sample. Analyses revealed a significant group difference in acquisition of information on both nonverbal (Brief Visuospatial Memory Test-Revised, BVMT-R total recall), F(1, 213) = 16.61, p < .001, and verbal (Hopkins Verbal Learning Test-Revised, HVLT-R total recall) learning tasks, F(1, 181) = 6.43, p < .01, and semantic fluency (Animal Naming), F(1, 232) = 7.57, p = .006, with the atypical group performing better on each task. Effect sizes were larger for nonverbal (Cohen's d = 0.66) than verbal learning (Cohen's d = 0.47) and semantic fluency (Cohen's d = 0.43). Individuals demonstrating an atypical pattern of performance on the CWIT inhibition/switching trial also demonstrated relative

  7. Folding wings like a cockroach: a review of transverse wing folding ensign wasps (Hymenoptera: Evaniidae: Afrevania and Trissevania.

    Directory of Open Access Journals (Sweden)

    István Mikó

    Full Text Available We revise two relatively rare ensign wasp genera, whose species are restricted to Sub-Saharan Africa: Afrevania and Trissevania. Afrevania longipetiolata sp. nov., Trissevania heatherae sp. nov., T. hugoi sp. nov., T. mrimaensis sp. nov. and T. slideri sp. nov. are described, males and females of T. anemotis and Afrevania leroyi are redescribed, and an identification key for Trissevaniini is provided. We argue that Trissevania mrimaensis sp. nov. and T. heatherae sp. nov. populations are vulnerable, given their limited distributions and threats from mining activities in Kenya. We hypothesize that these taxa together comprise a monophyletic lineage, Trissevaniini, tr. nov., the members of which share the ability to fold their fore wings along two intersecting fold lines. Although wing folding of this type has been described for the hind wing of some insects four-plane wing folding of the fore wing has never been documented. The wing folding mechanism and the pattern of wing folds of Trissevaniini is shared only with some cockroach species (Blattodea. It is an interesting coincidence that all evaniids are predators of cockroach eggs. The major wing fold lines of Trissevaniini likely are not homologous to any known longitudinal anatomical structures on the wings of other Evaniidae. Members of the new tribe share the presence of a coupling mechanism between the fore wing and the mesosoma that is composed of a setal patch on the mesosoma and the retinaculum of the fore wing. While the setal patch is an evolutionary novelty, the retinaculum, which originally evolved to facilitate fore and hind wing coupling in Hymenoptera, exemplifies morphological exaptation. We also refine and clarify the Semantic Phenotype approach used in previous taxonomic revisions and explore the consequences of merging new with existing data. The way that semantic statements are formulated can evolve in parallel, alongside improvements to the ontologies themselves.

  8. Basal Complex and Basal Venation of Odonata Wings: Structural Diversity and Potential Role in the Wing Deformation.

    Directory of Open Access Journals (Sweden)

    H Rajabi

    Full Text Available Dragonflies and damselflies, belonging to the order Odonata, are known to be excellent fliers with versatile flight capabilities. The ability to fly over a wide range of speeds, high manoeuvrability and great agility are a few characteristics of their flight. The architecture of the wings and their structural elements have been found to play a major role in this regard. However, the precise influence of individual wing components on the flight performance of these insects remains unknown. The design of the wing basis (so called basal complex and the venation of this part are responsible for particular deformability and specific shape of the wing blade. However, the wing bases are rather different in representatives of different odonate groups. This presumably reflects the dimensions of the wings on one hand, and different flight characteristics on the other hand. In this article, we develop the first three-dimensional (3D finite element (FE models of the proximal part of the wings of typical representatives of five dragonflies and damselflies families. Using a combination of the basic material properties of insect cuticle, a linear elastic material model and a nonlinear geometric analysis, we simulate the mechanical behaviour of the wing bases. The results reveal that although both the basal venation and the basal complex influence the structural stiffness of the wings, it is only the latter which significantly affects their deformation patterns. The use of numerical simulations enabled us to address the role of various wing components such as the arculus, discoidal cell and triangle on the camber formation in flight. Our study further provides a detailed representation of the stress concentration in the models. The numerical analysis presented in this study is not only of importance for understanding structure-function relationship of insect wings, but also might help to improve the design of the wings for biomimetic micro-air vehicles (MAVs.

  9. Distinguishing the effects of familiarity, relatedness, and color pattern rarity on attractiveness and measuring their effects on sexual selection in guppies (Poecilia reticulata).

    Science.gov (United States)

    Zajitschek, Susanne R K; Brooks, Robert C

    2008-12-01

    Mate choice is often based on multiple signal traits and can be influenced by context-dependent factors. Understanding the importance of these signals and factors can be difficult because they are often correlated and might interact. Here, we experimentally disentangle the effects of familiarity, kinship, pattern rarity, and ornament patterns on mate choice in guppies. We estimate whether these factors alter sexual selection on six phenotypic traits known to influence male attractiveness. Rarity of the male's phenotype is the only context-dependent factor that significantly influenced female mating decisions, with common patterns being least attractive. This preference for rare male patterns is a source of negative frequency-dependent selection that may contribute to maintaining the extreme polymorphism in male guppy coloration. Neither visual familiarity nor relatedness between mating partners had any significant effect on mate choice decisions. There was significant linear and nonlinear sexual selection on ornamental traits, but this was not influenced by the context-dependent measures. Our approach highlights the complexity of female mate choice and sexual selection, as well as the value of combining multifactorial experiments with multivariate selection analyses. Our study shows that both negative frequency-dependent selection and disruptive selection contribute to the maintenance of extreme polymorphism in guppies.

  10. Gait training assist system of a lower limb prosthetic visualizing muscle activation pattern using a color-depth sensor.

    Science.gov (United States)

    Ogata, Kunihiro; Mita, Tomoki; Tsuji, Toshiaki; Matsumoto, Yoshio

    2017-07-01

    Some unilateral lower-limb amputees load the intact limb more than the prosthetic limb. This can cause chronic pains, fatigue, lumbago, and joint diseases, including knee osteoarthritis. To avoid and counteract these symptoms it is necessary to improve their asymmetric gait. Increasing the function of the hip abductor muscle is important to maintaining symmetrical weight distribution. Therefore, the purpose of this study is to develop a training assist system, which estimates and visualizes an abductor muscle by using a color-depth sensor. To estimate the muscle activation, first, the floor reaction force is calculated using a simple dynamic model. Then, the hip torque is calculated using joint angles. The floor reaction force and, the muscle length are calculated based on a human musculoskeletal model. Muscle activity is estimated by these parameters. Evaluation experiments of this proposed method were performed on healthy persons and unilateral trans femoral amputees, and the effectiveness of this proposed algorithm has been confirmed.

  11. Temporal pattern of feeding activity in the firebug Pyrrhocoris apterus and its relation to sex, wing dimorphism and physiological state of adults

    Czech Academy of Sciences Publication Activity Database

    Socha, Radomír; Zemek, Rostislav

    2007-01-01

    Roč. 32, č. 1 (2007), s. 16-25 ISSN 0307-6962 R&D Projects: GA ČR GA206/03/0016 Institutional research plan: CEZ:AV0Z50070508 Keywords : feeding pattern * females * males Subject RIV: ED - Physiology Impact factor: 1.410, year: 2007

  12. Genomic sequence around butterfly wing development genes: annotation and comparative analysis.

    Directory of Open Access Journals (Sweden)

    Inês C Conceição

    Full Text Available BACKGROUND: Analysis of genomic sequence allows characterization of genome content and organization, and access beyond gene-coding regions for identification of functional elements. BAC libraries, where relatively large genomic regions are made readily available, are especially useful for species without a fully sequenced genome and can increase genomic coverage of phylogenetic and biological diversity. For example, no butterfly genome is yet available despite the unique genetic and biological properties of this group, such as diversified wing color patterns. The evolution and development of these patterns is being studied in a few target species, including Bicyclus anynana, where a whole-genome BAC library allows targeted access to large genomic regions. METHODOLOGY/PRINCIPAL FINDINGS: We characterize ∼1.3 Mb of genomic sequence around 11 selected genes expressed in B. anynana developing wings. Extensive manual curation of in silico predictions, also making use of a large dataset of expressed genes for this species, identified repetitive elements and protein coding sequence, and highlighted an expansion of Alcohol dehydrogenase genes. Comparative analysis with orthologous regions of the lepidopteran reference genome allowed assessment of conservation of fine-scale synteny (with detection of new inversions and translocations and of DNA sequence (with detection of high levels of conservation of non-coding regions around some, but not all, developmental genes. CONCLUSIONS: The general properties and organization of the available B. anynana genomic sequence are similar to the lepidopteran reference, despite the more than 140 MY divergence. Our results lay the groundwork for further studies of new interesting findings in relation to both coding and non-coding sequence: 1 the Alcohol dehydrogenase expansion with higher similarity between the five tandemly-repeated B. anynana paralogs than with the corresponding B. mori orthologs, and 2 the high

  13. [Signal Patterns of Dual Color Dual Fusion Fluorescence in Situ Hybridization for Detection of Genetic Abnormality in Adult Patients with ALL and Their Clinical Application].

    Science.gov (United States)

    Jiang, Mei; Zhang, Zhang-Lin; Xin, Yan-Hong; Liu, Shu-Yuan; Li, Xin; Wan, La-Gen

    2016-04-01

    To study the signal patterns of dual color dual fusion fluorescence in situ hybridization (DCDF-FISH) for detection of genetic abnormality in adult acute lymphoblastic leukemia (ALL) patients and their diagnostic value and clinical application. The clinical data of 68 ALL patients confirmed in our hospital were analyzed retrospectively; The bone marrow samples were detected by DCDF-FISH, flow cytometry, conventional cytogenetics (CCG), reverse transcriptase polymerase chain reaction (RT-PCR), and the correlation of these results was compared. And the reaction of patients to treatment was dynamically observed by DCDF-FISH. Sixteen signal patterns were found in DCDF-FISH, including 14 kinds of atypical signal patterns (signal patterns of 1R2G, 2R3G, 2R4G and 3R3G as abnormal signal patterns without BCR/ABL fusion gene. Signal patterns of 1R1G1F, 1R1G3F, 1R1G4F, 1R2G1F, 1R2G2F, 1R2G3F, 1RnG2F (n ≥ 3), 2R2G1F, 1G4F, 1R4F corresponded to t (9;22) karyotype). Ph(+) ALL patients accounted for 17. All cases with Ph chromosome or BCR/ABL positive were B-ALL or My(+)-B-ALL. The Ph chromosome was detected in 12 cases (positive rate was 18%) by CCG. The positive rate was 25% (17/68) by DCDF-FISH and RT-PCR. The DCDF-FISH fluorescence pattern change before and after chemotherapy of the patients showed that the quantity and form of the signal pattern was changed after chemotherapy, and the common characteristics was the Ph chromosome in patients. The DCDF-FISH is a sensitive and reliable method for the detection of BCR/ABL rearrangement. Analyzing the dynamical change of DCDF-FISH signal patterns has been comfirmed to have a important guiding significance in the diagnosis, and anlysis of response to therapy, drug resistance and the prognosis of ALL patients.

  14. Early Birds by Light at Night: Effects of Light Color and Intensity on Daily Activity Patterns in Blue Tits

    NARCIS (Netherlands)

    de Jong, Maaike; Caro, Samuel P.; Gienapp, Phillip; Spoelstra, Kamiel; Visser, Marcel E.

    2017-01-01

    Artificial light at night disturbs the daily rhythms of many organisms. To what extent this disturbance depends on the intensity and spectral composition of light remain obscure. Here, we measured daily activity patterns of captive blue tits (Cyanistes caeruleus) exposed to similar intensities of

  15. The Dominance of Spatial Memory over Color or Form in 3- to 5-Year-Olds' Pattern Reconstructions.

    Science.gov (United States)

    Cocking, Rodney R.

    The relative importance of spatial-position as a memory aid in a block pattern reproduction task was investigated by analyzing the object-selection and object-placement strategies of 69 nursery school children. Subjects were given a task modeled on Piaget's assessment of Static Reproductive Images and Action that had been modified into a…

  16. WINGS Data Release

    DEFF Research Database (Denmark)

    Moretti, A.; Poggianti, B. M.; Fasano, G.

    2014-01-01

    Context. To effectively investigate galaxy formation and evolution, it is of paramount importance to exploit homogeneous data for large samples of galaxies in different environments. Aims. The WIde-field Nearby Galaxy-cluster Survey (WINGS) project aim is to evaluate physical properties of galaxies...... in a complete sample of low redshift clusters to be used as reference sample for evolutionary studies. The WINGS survey is still ongoing and the original dataset will be enlarged with new observations. This paper presents the entire collection of WINGS measurements obtained so far. Methods. We decided to make......, and on the cluster redshift, reaching on average 90% at V ≲ 21.7. Near-infrared photometric catalogs for 26 (in K) and 19 (in J) clusters are part of the database and the number of sources is 962 344 in K and 628 813 in J. Here again the completeness depends on the data quality, but it is on average higher than 90...

  17. Pattern Recognition in Numerical Data Sets and Color Images through the Typicality Based on the GKPFCM Clustering Algorithm

    Directory of Open Access Journals (Sweden)

    B. Ojeda-Magaña

    2013-01-01

    Full Text Available We take the concept of typicality from the field of cognitive psychology, and we apply the meaning to the interpretation of numerical data sets and color images through fuzzy clustering algorithms, particularly the GKPFCM, looking to get better information from the processed data. The Gustafson Kessel Possibilistic Fuzzy c-means (GKPFCM is a hybrid algorithm that is based on a relative typicality (membership degree, Fuzzy c-means and an absolute typicality (typicality value, Possibilistic c-means. Thus, using both typicalities makes it possible to learn and analyze data as well as to relate the results with the theory of prototypes. In order to demonstrate these results we use a synthetic data set and a digitized image of a glass, in a first example, and images from the Berkley database, in a second example. The results clearly demonstrate the advantages of the information obtained about numerical data sets, taking into account the different meaning of typicalities and the availability of both values with the clustering algorithm used. This approach allows the identification of small homogeneous regions, which are difficult to find.

  18. Temporal variation of wing geometry in Aedes albopictus

    Directory of Open Access Journals (Sweden)

    Paloma Oliveira Vidal

    2012-12-01

    Full Text Available Although native to the tropical and subtropical areas of Southeast Asia, Aedes albopictus is now found on five continents, primarily due to its great capacity to adapt to different environments. This species is considered a secondary vector of dengue virus in several countries. Wing geometric morphometrics is widely used to furnish morphological markers for the characterisation and identification of species of medical importance and for the assessment of population dynamics. In this work, we investigated the metric differentiation of the wings of Ae. albopictus samples collected over a four-year period (2007-2010 in São Paulo, Brazil. Wing size significantly decreased during this period for both sexes and the wing shape also changed over time, with the wing shapes of males showing greater differences after 2008 and those of females differing more after 2009. Given that the wings play sex-specific roles, these findings suggest that the males and females could be affected by differential evolutionary pressures. Consistent with this hypothesis, a sexually dimorphic pattern was detected and quantified: the females were larger than the males (with respect to the mean and had a distinct wing shape, regardless of allometric effects. In conclusion, wing alterations, particularly those involving shape, are a sensitive indicator of microevolutionary processes in this species.

  19. Temporal variation of wing geometry in Aedes albopictus.

    Science.gov (United States)

    Vidal, Paloma Oliveira; Carvalho, Eneas; Suesdek, Lincoln

    2012-12-01

    Although native to the tropical and subtropical areas of Southeast Asia, Aedes albopictus is now found on five continents, primarily due to its great capacity to adapt to different environments. This species is considered a secondary vector of dengue virus in several countries. Wing geometric morphometrics is widely used to furnish morphological markers for the characterisation and identification of species of medical importance and for the assessment of population dynamics. In this work, we investigated the metric differentiation of the wings of Ae. albopictus samples collected over a four-year period (2007-2010) in São Paulo, Brazil. Wing size significantly decreased during this period for both sexes and the wing shape also changed over time, with the wing shapes of males showing greater differences after 2008 and those of females differing more after 2009. Given that the wings play sex-specific roles, these findings suggest that the males and females could be affected by differential evolutionary pressures. Consistent with this hypothesis, a sexually dimorphic pattern was detected and quantified: the females were larger than the males (with respect to the mean) and had a distinct wing shape, regardless of allometric effects. In conclusion, wing alterations, particularly those involving shape, are a sensitive indicator of microevolutionary processes in this species.

  20. Eye Movement Preferences As Individual Differences in Learning From Color and Non-Color Pictures.

    Science.gov (United States)

    Caban, Juan Pedro

    An experiment compared the effectiveness of color and non-color (black-and-white) pictures in a paired associate learning task. The study also used individual eye movement quantifications as a predictor of preference for color and non-color pictures. Specifically, eye movement fixation patterns were used as indices of preference for color and…

  1. Coloration mechanisms and phylogeny of Morpho butterflies.

    Science.gov (United States)

    Giraldo, M A; Yoshioka, S; Liu, C; Stavenga, D G

    2016-12-15

    Morpho butterflies are universally admired for their iridescent blue coloration, which is due to nanostructured wing scales. We performed a comparative study on the coloration of 16 Morpho species, investigating the morphological, spectral and spatial scattering properties of the differently organized wing scales. In numerous previous studies, the bright blue Morpho coloration has been fully attributed to the multi-layered ridges of the cover scales' upper laminae, but we found that the lower laminae of the cover and ground scales play an important additional role, by acting as optical thin film reflectors. We conclude that Morpho coloration is a subtle combination of overlapping pigmented and/or unpigmented scales, multilayer systems, optical thin films and sometimes undulated scale surfaces. Based on the scales' architecture and their organization, five main groups can be distinguished within the genus Morpho, largely agreeing with the accepted phylogeny. © 2016. Published by The Company of Biologists Ltd.

  2. WHEN COMPASSION GROWS WINGS

    African Journals Online (AJOL)

    Nicky

    antiretroviral roll-out in full swing, the. WHEN COMPASSION GROWS WINGS. The free time and expertise given by its deeply committed core of professional volunteers. (including pilots) is the lifeblood of the operation. Red Cross Air Mercy Service volunteer, German national Dr Florian Funk, at the AMS Durban base.

  3. Twisted Winged Endoparasitoids

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 9; Issue 10. Twisted Winged Endoparasitoids - An Enigma for Entomologists. Alpana Mazumdar. General Article Volume 9 Issue 10 October 2004 pp 19-24. Fulltext. Click here to view fulltext PDF. Permanent link:

  4. Transluminal color-coded three-dimensional magnetic resonance angiography for visualization of signal Intensity distribution pattern within an unruptured cerebral aneurysm: preliminarily assessment with anterior communicating artery aneurysms

    International Nuclear Information System (INIS)

    Satoh, T.; Ekino, C.; Ohsako, C.

    2004-01-01

    The natural history of unruptured cerebral aneurysm is not known; also unknown is the potential growth and rupture in any individual aneurysm. The authors have developed transluminal color-coded three-dimensional magnetic resonance angiography (MRA) obtained by a time-of-flight sequence to investigate the interaction between the intra-aneurysmal signal intensity distribution patterns and configuration of unruptured cerebral aneurysms. Transluminal color-coded images were reconstructed from volume data of source magnetic resonance angiography by using a parallel volume-rendering algorithm with transluminal imaging technique. By selecting a numerical threshold range from a signal intensity opacity chart of the three-dimensional volume-rendering dataset several areas of signal intensity were depicted, assigned different colors, and visualized transparently through the walls of parent arteries and an aneurysm. Patterns of signal intensity distribution were analyzed with three operated cases of an unruptured anterior communicating artery aneurysm and compared with the actual configurations observed at microneurosurgery. A little difference in marginal features of an aneurysm was observed; however, transluminal color-coded images visualized the complex signal intensity distribution within an aneurysm in conjunction with aneurysmal geometry. Transluminal color-coded three-dimensional magnetic resonance angiography can thus provide numerical analysis of the interaction between spatial signal intensity distribution patterns and aneurysmal configurations and may offer an alternative and practical method to investigate the patient-specific natural history of individual unruptured cerebral aneurysms. (orig.)

  5. Color Algebras

    Science.gov (United States)

    Mulligan, Jeffrey B.

    2017-01-01

    A color algebra refers to a system for computing sums and products of colors, analogous to additive and subtractive color mixtures. The difficulty addressed here is the fact that, because of metamerism, we cannot know with certainty the spectrum that produced a particular color solely on the basis of sensory data. Knowledge of the spectrum is not required to compute additive mixture of colors, but is critical for subtractive (multiplicative) mixture. Therefore, we cannot predict with certainty the multiplicative interactions between colors based solely on sensory data. There are two potential applications of a color algebra: first, to aid modeling phenomena of human visual perception, such as color constancy and transparency; and, second, to provide better models of the interactions of lights and surfaces for computer graphics rendering.

  6. Ocean Color

    Data.gov (United States)

    National Aeronautics and Space Administration — Satellite-derived Ocean Color Data sets from historical and currently operational NASA and International Satellite missions including the NASA Coastal Zone Color...

  7. Color naming

    OpenAIRE

    Şahin, Ebru

    1998-01-01

    Ankara : Bilkent University, Department of Interior Architecture and Environmental Design and Institute of Fine Arts, 1998. Thesis (Ph.D) -- Bilkent University, 1998 Includes bibliographical refences. In this study, visual aspects of color and neurophysiological processes involved in the phenomenon, language of color and color models were explained in addition to the discussion of different ideas, orientations and previous works behind the subject of matter. Available color ...

  8. Fuzzy boundaries: color and gene flow patterns among parapatric lineages of the western shovel-nosed snake and taxonomic implication

    Science.gov (United States)

    Wood, Dustin A.; Fisher, Robert N.; Vandergast, Amy G.

    2014-01-01

    Accurate delineation of lineage diversity is increasingly important, as species distributions are becoming more reduced and threatened. During the last century, the subspecies category was often used to denote phenotypic variation within a species range and to provide a framework for understanding lineage differentiation, often considered incipient speciation. While this category has largely fallen into disuse, previously recognized subspecies often serve as important units for conservation policy and management when other information is lacking. In this study, we evaluated phenotypic subspecies hypotheses within shovel-nosed snakes on the basis of genetic data and considered how evolutionary processes such as gene flow influenced possible incongruence between phenotypic and genetic patterns. We used both traditional phylogenetic and Bayesian clustering analyses to infer range-wide genetic structure and spatially explicit analyses to detect possible boundary locations of lineage contact. Multilocus analyses supported three historically isolated groups with low to moderate levels of contemporary gene exchange. Genetic data did not support phenotypic subspecies as exclusive groups, and we detected patterns of discordance in areas where three subspecies are presumed to be in contact. Based on genetic and phenotypic evidence, we suggested that species-level diversity is underestimated in this group and we proposed that two species be recognized, Chionactis occipitalis and C. annulata. In addition, we recommend retention of two subspecific designations within C. annulata (C. a. annulata and C. a. klauberi) that reflect regional shifts in both genetic and phenotypic variation within the species. Our results highlight the difficultly in validating taxonomic boundaries within lineages that are evolving under a time-dependent, continuous process.

  9. Logistics Supply of the Distributed Air Wing

    Science.gov (United States)

    2014-09-01

    Event Graph The Consumption Process first instantiates the variables . The model follows a conveyor belt pattern, whereby after processing an event...to any part of the world. A capstone project, conducted by the system engineering curriculum, proposed to distribute the air assets from the aircraft...SUBJECT TERMS distributed air wing, logistics, supply, unmanned air systems , cargo UAS, unmanned systems , discrete event simulation, vehicle routing

  10. Thermal maturity patterns in the Ordovician and Devonian of Pennsylvania using conodont color alteration index (CAI) and vitrinite reflectance (%Ro)

    Science.gov (United States)

    Repetski, J.E.; Ryder, R.T.; Harper, J.A.; Trippi, M.H.

    2006-01-01

    This new series of maps enhances previous thermal maturity maps in Pennsylvania by establishing: 1) new subsurface CAI data points for the Ordovician and Devonian and 2) new %Ro and Rock Eval subsurface data points for Middle and Upper Devonian black shale units. Thermal maturity values for the Ordovician and Devonian strata are of major interest because they contain the source rocks for most of the oil and natural gas resources in the basin. Thermal maturity patterns of the Middle Ordovician Trenton Group are evaluated here because they closely approximate those of the overlying Ordovician Utica Shale that is believed to be the source rock for the regional oil and gas accumulation in Lower Silurian sandstones and for natural gas fields in fractured dolomite reservoirs of the Ordovician Black River-Trenton Limestones. Improved CAI-based thermal maturity maps of the Ordovician are important to identify areas of optimum gas generation from the Utica Shale and to provide constraints for interpreting the origin of oil and gas in the Lower Silurian regional accumulation and Ordovician Black River-Trenton fields. Thermal maturity maps of the Devonian will better constrain burial history-petroleum generation models of the Utica Shale, as well as place limitations on the origin of regional oil and gas accumulations in Upper Devonian sandstone and Middle to Upper Devonian black shale.

  11. Synthesis and Examination of Polymers to Improve Pattern Clarity and Resistance Properties of Phthalocyanine Color Pixels in Liquid Crystal Display

    International Nuclear Information System (INIS)

    Yoon, Chun; Choi, Jae Hong; Kim, Jae Pil

    2011-01-01

    The study was responding to several purposes for LCD that required the introduction of new binders. First, the traditional binder, widely used for a long time, was prepared from benzyl methacrylate and methacrylic acid, which is not suitable for the recent trend of blue pigment. The recent blue pigment (CI Pigment Blue 15:6) is a derivative of phthalocyanine, with smaller particle size to obtain a high contrast ratio. The pigments for a high contrast ratio usually have a particle size in the range of 40-60 nm, while conventional pigments have a particle size of around 90 nm. Figure 1 shows the chemical structure and an electron microscope image (TEM) of recent phthalocyanine blue pigment with very fine particle shape. The smaller sized pigment usually has a larger surface area, which should increase interactions among particles resulting in poor properties such as agglomeration, poor pattern clarity and resistance.10 To minimize the above drawbacks, which increase the influences of binders on pigment particles, monomers such as 2-hydroxyethyl methacrylate and hydroxybutyl methacrylate were introduced to produce a hydrogen bond between the binder and the pigment

  12. Biomimetics, color, and the arts

    Science.gov (United States)

    Schenk, Franziska

    2015-03-01

    Color as dramatic, dynamic and dazzling as the iridescent hues on the wings of certain butterflies has never been encountered in the art world. Unlike and unmatched by the chemical pigments of the artists' palette, this changeable color is created by transparent, colorless nanostructures that, as with prisms, diffract and reflect light to render spectral color visible. Until now, iridescent colors, by their very nature, have defied artists' best efforts to fully capture these rainbow hues. Now, for the first time, the artist and researcher Franziska Schenk employs latest nature-inspired color-shift technology to actually simulate the iridescence of butterflies and beetles on canvas. Crucially, studying the ingenious ways in which a range of such displays are created by insects has provided the artist with vital clues on how to adapt and adopt these challenging optical nano-materials for painting. And indeed, after years of meticulous and painstaking research both in the lab and studio, the desired effect is achieved. The resulting paintings, like an iridescent insect, do in fact fluctuate in perceived color - depending on the light and viewing angle. In tracing the artist's respective biomimetic approach, the paper not only provides an insight into the new color technology's evolution and innovative artistic possibilities, but also suggests what artists can learn from nature.

  13. Color Categories and Color Appearance

    Science.gov (United States)

    Webster, Michael A.; Kay, Paul

    2012-01-01

    We examined categorical effects in color appearance in two tasks, which in part differed in the extent to which color naming was explicitly required for the response. In one, we measured the effects of color differences on perceptual grouping for hues that spanned the blue-green boundary, to test whether chromatic differences across the boundary…

  14. Design optimization of deployable wings

    Science.gov (United States)

    Gaddam, Pradeep

    Morphing technology is an important aspect of UAV design, particularly in regards to deployable systems. The design of such system has an important impact on the vehicle's performance. The primary focus of the present research work was to determine the most optimum deployable wing design from 3 competing designs and develop one of the deployable wing designs to test in the research facility. A Matlab code was developed to optimize 3 deployable wing concepts inflatable, inflatable telescopic and rigid-folding wings based on a sequential optimization strategy. The constraints that were part of the code include the packaging constraints during its stowed state, fixed length of the deployed section and the minimum L/D constraint. This code resulted in determining the optimum weight of all the 3 designs, the most optimum weight design is the inflatable wing design. This is a result of the flexible skin material and also due to no rigid parts in the deployed wing section. Another goal of the research involved developing an inflatable telescopic wing. The prototype was tested in a wind tunnel, while the actual wing was tested in the altitude chamber to determine the deployment speed, input pressure, analyze and predict the deployment sequence and behavior of the wing at such high wind speeds and altitudes ranging from 60,000 ft to 90,000 ft. Results from these tests allowed us to conclude the deployment sequence of the telescopic wing followed from the root to the tip section. The results were used to analyze the deployment time of the wing. As expected the deployment time decreased with an increase in input pressure. The results also show us that as the altitude increases, the deployment speed of the wing also increased. This was demonstrated when the wing was tested at a maximum altitude pressure of 90,000ft, well above the design altitude of 60,000ft.

  15. Low Aspect-Ratio Wings for Wing-Ships

    DEFF Research Database (Denmark)

    Filippone, Antonino; Selig, M.

    1998-01-01

    Flying on ground poses technical and aerodynamical challenges. The requirements for compactness, efficiency, manouverability, off-design operation,open new areas of investigations in the fieldof aerodynamic analysis and design. A review ofthe characteristics of low-aspect ratio wings, in- and out...... of ground, is presented. It is shownthat the performance of such wings is generally inferior to that of slender wings, although in ground placement can yield substantial improvements in the aerodynamic efficiency....

  16. Color Analysis

    Science.gov (United States)

    Wrolstad, Ronald E.; Smith, Daniel E.

    Color, flavor, and texture are the three principal quality attributes that determine food acceptance, and color has a far greater influence on our judgment than most of us appreciate. We use color to determine if a banana is at our preferred ripeness level, and a discolored meat product can warn us that the product may be spoiled. The marketing departments of our food corporations know that, for their customers, the color must be "right." The University of California Davis scorecard for wine quality designates four points out of 20, or 20% of the total score, for color and appearance (1). Food scientists who establish quality control specifications for their product are very aware of the importance of color and appearance. While subjective visual assessment and use of visual color standards are still used in the food industry, instrumental color measurements are extensively employed. Objective measurement of color is desirable for both research and industrial applications, and the ruggedness, stability, and ease of use of today's color measurement instruments have resulted in their widespread adoption.

  17. Processing of Color Words Activates Color Representations

    Science.gov (United States)

    Richter, Tobias; Zwaan, Rolf A.

    2009-01-01

    Two experiments were conducted to investigate whether color representations are routinely activated when color words are processed. Congruency effects of colors and color words were observed in both directions. Lexical decisions on color words were faster when preceding colors matched the color named by the word. Color-discrimination responses…

  18. Cross Shelf Patterns in Habitat Selectivity of Hawkfish (Family: Cirrhitidae) in the Red Sea; with a Special Case of Varying Color Morphs in Paracirrhites forsteri.

    KAUST Repository

    Chaidez, Veronica

    2015-01-01

    Not much is known about hawkfish worldwide including those that occur in the understudied Red Sea reef system. Hawkfishes are small reef predators that perch in ambush-ready positions and shelter within or on various substrates including live and dead coral. The aim of this study was to look at the distribution and abundance patterns of Red Sea hawkfishes across an inshore and offshore gradient and to investigate the use of benthic habitats. This study was conducted on three inshore, four midshore, and two offshore reefs with surveys at 8 meters and along the reef crest. In total, three species were documented: Paracirrhites forsteri, Cirrhitichthys oxycephalus, and Cirrhitus spilotoceps. We found clear distinctions between depth zones and between continental shelf positions. Cirrhitichthys oxycephalus only occurs at the reef slope and Cirrhitus spilotoceps is only found on reef crests. Paracirrhites forsteri was the most abundant species across all reefs and was found in four varying color morphs. Morph 1 showed the most evidence of being a generalist as it utilized the greatest number of substrates. All three species were more abundant on midshore and offshore reefs which have healthier, intact coral communities. Coral cover is a good indicator of hawkfish abundance even when the species in question does not utilize live coral directly.

  19. Colored operads

    CERN Document Server

    Yau, Donald

    2016-01-01

    The subject of this book is the theory of operads and colored operads, sometimes called symmetric multicategories. A (colored) operad is an abstract object which encodes operations with multiple inputs and one output and relations between such operations. The theory originated in the early 1970s in homotopy theory and quickly became very important in algebraic topology, algebra, algebraic geometry, and even theoretical physics (string theory). Topics covered include basic graph theory, basic category theory, colored operads, and algebras over colored operads. Free colored operads are discussed in complete detail and in full generality. The intended audience of this book includes students and researchers in mathematics and other sciences where operads and colored operads are used. The prerequisite for this book is minimal. Every major concept is thoroughly motivated. There are many graphical illustrations and about 150 exercises. This book can be used in a graduate course and for independent study.

  20. Pretreated Butterfly Wings for Tuning the Selective Vapor Sensing

    Science.gov (United States)

    Piszter, Gábor; Kertész, Krisztián; Bálint, Zsolt; Biró, László Péter

    2016-01-01

    Photonic nanoarchitectures occurring in the scales of Blue butterflies are responsible for their vivid blue wing coloration. These nanoarchitectures are quasi-ordered nanocomposites which are constituted from a chitin matrix with embedded air holes. Therefore, they can act as chemically selective sensors due to their color changes when mixing volatile vapors in the surrounding atmosphere which condensate into the nanoarchitecture through capillary condensation. Using a home-built vapor-mixing setup, the spectral changes caused by the different air + vapor mixtures were efficiently characterized. It was found that the spectral shift is vapor-specific and proportional with the vapor concentration. We showed that the conformal modification of the scale surface by atomic layer deposition and by ethanol pretreatment can significantly alter the optical response and chemical selectivity, which points the way to the efficient production of sensor arrays based on the knowledge obtained through the investigation of modified butterfly wings. PMID:27618045

  1. Color metallography

    International Nuclear Information System (INIS)

    Hasson, Raymond.

    1976-06-01

    After a short introduction explaining the reasons why color metallography was adopted, the various operations involved in this technique are described in turn and illustrated by colored photomicrographs. The sample preparation (cutting, covering) and surface preparation (trimming, polishing, finishing) are described briefly. The operations specific to color metallography are then detailed: revelation of the structure of polished surfaces, dye impregnation techniques, optical systems used in macrography, in micrography, different light sources used in microscopy, photographic methods [fr

  2. COLOR IMAGES

    Directory of Open Access Journals (Sweden)

    Dominique Lafon

    2011-05-01

    Full Text Available The goal of this article is to present specific capabilities and limitations of the use of color digital images in a characterization process. The whole process is investigated, from the acquisition of digital color images to the analysis of the information relevant to various applications in the field of material characterization. A digital color image can be considered as a matrix of pixels with values expressed in a vector-space (commonly 3 dimensional space whose specificity, compared to grey-scale images, is to ensure a coding and a representation of the output image (visualisation printing that fits the human visual reality. In a characterization process, it is interesting to regard color image attnbutes as a set of visual aspect measurements on a material surface. Color measurement systems (spectrocolorimeters, colorimeters and radiometers and cameras use the same type of light detectors: most of them use Charge Coupled Devices sensors. The difference between the two types of color data acquisition systems is that color measurement systems provide a global information of the observed surface (average aspect of the surface: the color texture is not taken into account. Thus, it seems interesting to use imaging systems as measuring instruments for the quantitative characterization of the color texture.

  3. Wing sexual dimorphism of pathogen-vector culicids.

    Science.gov (United States)

    Virginio, Flávia; Oliveira Vidal, Paloma; Suesdek, Lincoln

    2015-03-14

    Sexual dimorphism in animals has been studied from different perspectives for decades. In 1874 Darwin hypothesized that it was related to sexual selection, and even after nearly 140 years, when additional empirical data has become available and the subject has been investigated from a contemporary viewpoint, this idea is still supported. Although mosquito (Culicidae) wings are of great importance as they play a sex-specific role, little is known about wing sexual dimorphism in these pathogen-vector insects. Detection and characterization of wing sexual dimorphism in culicids may indirectly enhance our knowledge of their epidemiology or reveal sex-linked genes, aspects that have been discussed by vector control initiatives and developers of genetically modified mosquitoes. Using geometric morphometrics, we carried out a comparative assessment of wing sexual dimorphism in ten culicid species of medical/veterinary importance from genera Culex, Aedes, Anopheles and Ochlerotatus collected in Brazil. Discriminant analysis revealed significant sexual dimorphism in all the species studied, indicating that phenotypic expression of wing shape in mosquitoes is indeed sex-specific. A cross-validated test performed to reclassify the sexes with and without allometry yielded very similar results. Mahalanobis distances among the ten species showed that the species had different patterns of shape sexual dimorphism and that females are larger than males in some species. Wing morphology differed significantly between species. The finding of sexual dimorphism in all the species would suggest that the wing geometry of Culicidae is canalized. Although sexual dimorphism is prevalent, species-specific patterns occur. Allometry was not the main determinant of sexual dimorphism, which suggests that sexual selection or other evolutionary mechanisms underlie wing sexual dimorphism in these insects.

  4. Structural color mechanism in the Papilio blumei butterfly.

    Science.gov (United States)

    Lo, Mei-Ling; Lee, Cheng-Chung

    2014-02-01

    The structural color found in biological systems has complicated nanostructure. It is very important to determine its color mechanism. In this study, the 2D photonic crystal structures of the Papilio blumei butterfly were constructed, and the corresponding reflectance spectra were simulated by the finite-difference time-domain method. The structural color of the butterfly depends on the incident angle of light, film thickness, film material (film refractive index), and the size of the air hole (effective refractive index). Analysis of simulations can help us understand the hue, brightness, and saturation of structural color on the butterfly wing. As a result, the analysis can help us fabricate expected structural color.

  5. Wing defects in Drosophila xenicid mutant clones are caused by C-terminal deletion of additional sex combs (Asx).

    Science.gov (United States)

    Bischoff, Kara; Ballew, Anna C; Simon, Michael A; O'Reilly, Alana M

    2009-12-01

    The coordinated action of genes that control patterning, cell fate determination, cell size, and cell adhesion is required for proper wing formation in Drosophila. Defects in any of these basic processes can lead to wing aberrations, including blisters. The xenicid mutation was originally identified in a screen designed to uncover regulators of adhesion between wing surfaces [1]. Here, we demonstrate that expression of the betaPS integrin or the patterning protein Engrailed are not affected in developing wing imaginal discs in xenicid mutants. Instead, expression of the homeotic protein Ultrabithorax (Ubx) is strongly increased in xenicid mutant cells. Our results suggest that upregulation of Ubx transforms cells from a wing blade fate to a haltere fate, and that the presence of haltere cells within the wing blade is the primary defect leading to the adult wing phenotypes observed.

  6. Wing defects in Drosophila xenicid mutant clones are caused by C-terminal deletion of additional sex combs (Asx.

    Directory of Open Access Journals (Sweden)

    Kara Bischoff

    2009-12-01

    Full Text Available The coordinated action of genes that control patterning, cell fate determination, cell size, and cell adhesion is required for proper wing formation in Drosophila. Defects in any of these basic processes can lead to wing aberrations, including blisters. The xenicid mutation was originally identified in a screen designed to uncover regulators of adhesion between wing surfaces [1].Here, we demonstrate that expression of the betaPS integrin or the patterning protein Engrailed are not affected in developing wing imaginal discs in xenicid mutants. Instead, expression of the homeotic protein Ultrabithorax (Ubx is strongly increased in xenicid mutant cells.Our results suggest that upregulation of Ubx transforms cells from a wing blade fate to a haltere fate, and that the presence of haltere cells within the wing blade is the primary defect leading to the adult wing phenotypes observed.

  7. Colored leptons

    International Nuclear Information System (INIS)

    Harari, H.

    1985-01-01

    If leptons are composite and if they contain colored preons, one expects the existence of heavy color-octet fermions with quantum numbers similar to those of ordinary leptons. Such a ''colored lepton'' should decay into a gluon and a lepton, yielding a unique experimental signature. Charged ''colored leptons'' probably have masses of the order of the compositeness scale Λ > or approx. 1 TeV. They may be copiously produced at future multi-TeV e + e - , ep and hadron colliders. ''Colored neutrinos'' may have both Dirac and Majorana masses. They could be much lighter than Λ, possibly as light as 100 GeV or less. In such a case they should be readily produced at the CERN anti pp collider, yielding spectacular monojet and dijet events. They may also be produced at LEP and HERA. (orig.)

  8. Aeroelastic Wing Shaping Using Distributed Propulsion

    Science.gov (United States)

    Nguyen, Nhan T. (Inventor); Reynolds, Kevin Wayne (Inventor); Ting, Eric B. (Inventor)

    2017-01-01

    An aircraft has wings configured to twist during flight. Inboard and outboard propulsion devices, such as turbofans or other propulsors, are connected to each wing, and are spaced along the wing span. A flight controller independently controls thrust of the inboard and outboard propulsion devices to significantly change flight dynamics, including changing thrust of outboard propulsion devices to twist the wing, and to differentially apply thrust on each wing to change yaw and other aspects of the aircraft during various stages of a flight mission. One or more generators can be positioned upon the wing to provide power for propulsion devices on the same wing, and on an opposite wing.

  9. Stiffness of desiccating insect wings

    Energy Technology Data Exchange (ETDEWEB)

    Mengesha, T E; Vallance, R R [Department of Mechanical Engineering, The George Washington University, 738 Phillips Hall, 801 22nd St NW, Washington, DC 20052 (United States); Mittal, R, E-mail: vallance@gwu.edu [Department of Mechanical Engineering, Johns Hopkins University, 126 Latrobe Hall, 3400 N Charles Street, Baltimore, MD 21218 (United States)

    2011-03-15

    The stiffness of insect wings is typically determined through experimental measurements. Such experiments are performed on wings removed from insects. However, the wings are subject to desiccation which typically leads to an increase in their stiffness. Although this effect of desiccation is well known, a comprehensive study of the rate of change in stiffness of desiccating insect wings would be a significant aid in planning experiments as well as interpreting data from such experiments. This communication presents a comprehensive experimental analysis of the change in mass and stiffness of gradually desiccating forewings of Painted Lady butterflies (Vanessa cardui). Mass and stiffness of the forewings of five butterflies were simultaneously measured every 10 min over a 24 h period. The averaged results show that wing mass declined exponentially by 21.1% over this time period with a time constant of 9.8 h, while wing stiffness increased linearly by 46.2% at a rate of 23.4 {mu}N mm{sup -1} h{sup -1}. For the forewings of a single butterfly, the experiment was performed over a period of 1 week, and the results show that wing mass declined exponentially by 52.2% with a time constant of 30.2 h until it reached a steady-state level of 2.00 mg, while wing stiffness increased exponentially by 90.7% until it reached a steady-state level of 1.70 mN mm{sup -1}. (communication)

  10. A new species of Homalocerus Schoenherr from the Atlantic coast of the State of São Paulo, Brazil (Coleoptera, Belidae, Belinae, with notes on color pattern and on the sclerites of the internal sac

    Directory of Open Access Journals (Sweden)

    Sergio A. Vanin

    2014-03-01

    Full Text Available A new species of Homalocerus Schoenherr from the Atlantic coast of the State of São Paulo, Brazil (Coleoptera, Belidae, Belinae, with notes on color pattern and on the sclerites of the internal sac. Homalocerus bimaculatus sp. nov. (type locality: Brazil, São Paulo is described and illustrated, and comments on the sclerites of the internal sac of aedeagus and on color pattern are provided. The new species is compared to other similar species of the genus, being distinguished by having three clusters of carmine pubescence on pronotum and two lateral whitish oval spots located slightly before the middle of each elytron. Six species of Homalocerus, including the new one, are known from the State of São Paulo. The previously published identification key for species of Homalocerus is updated to include H. bimaculatus.

  11. AERODYNAMICS OF WING TIP SAILS

    Directory of Open Access Journals (Sweden)

    MUSHTAK AL-ATABI

    2006-06-01

    Full Text Available Observers have always been fascinated by soaring birds. An interesting feature of these birds is the existence of few feathers extending from the tip of the wing. In this paper, small lifting surfaces were fitted to the tip of a NACA0012 wing in a fashion similar to that of wing tip feathers. Experimental measurements of induced drag, longitudinal static stability and trailing vortex structure were obtained.The tests showed that adding wing tip surfaces (sails decreased the induced drag factor and increased the longitudinal static stability. Results identified two discrete appositely rotated tip vortices and showed the ability of wing tip surfaces to break them down and to diffuse them.

  12. Structural dynamics and aerodynamics measurements of biologically inspired flexible flapping wings.

    Science.gov (United States)

    Wu, P; Stanford, B K; Sällström, E; Ukeiley, L; Ifju, P G

    2011-03-01

    Flapping wing flight as seen in hummingbirds and insects poses an interesting unsteady aerodynamic problem: coupling of wing kinematics, structural dynamics and aerodynamics. There have been numerous studies on the kinematics and aerodynamics in both experimental and computational cases with both natural and artificial wings. These studies tend to ignore wing flexibility; however, observation in nature affirms that passive wing deformation is predominant and may be crucial to the aerodynamic performance. This paper presents a multidisciplinary experimental endeavor in correlating a flapping micro air vehicle wing's aeroelasticity and thrust production, by quantifying and comparing overall thrust, structural deformation and airflow of six pairs of hummingbird-shaped membrane wings of different properties. The results show that for a specific spatial distribution of flexibility, there is an effective frequency range in thrust production. The wing deformation at the thrust-productive frequencies indicates the importance of flexibility: both bending and twisting motion can interact with aerodynamic loads to enhance wing performance under certain conditions, such as the deformation phase and amplitude. By measuring structural deformations under the same aerodynamic conditions, beneficial effects of passive wing deformation can be observed from the visualized airflow and averaged thrust. The measurements and their presentation enable observation and understanding of the required structural properties for a thrust effective flapping wing. The intended passive responses of the different wings follow a particular pattern in correlation to their aerodynamic performance. Consequently, both the experimental technique and data analysis method can lead to further studies to determine the design principles for micro air vehicle flapping wings.

  13. Structural dynamics and aerodynamics measurements of biologically inspired flexible flapping wings

    International Nuclear Information System (INIS)

    Wu, P; Stanford, B K; Ifju, P G; Saellstroem, E; Ukeiley, L

    2011-01-01

    Flapping wing flight as seen in hummingbirds and insects poses an interesting unsteady aerodynamic problem: coupling of wing kinematics, structural dynamics and aerodynamics. There have been numerous studies on the kinematics and aerodynamics in both experimental and computational cases with both natural and artificial wings. These studies tend to ignore wing flexibility; however, observation in nature affirms that passive wing deformation is predominant and may be crucial to the aerodynamic performance. This paper presents a multidisciplinary experimental endeavor in correlating a flapping micro air vehicle wing's aeroelasticity and thrust production, by quantifying and comparing overall thrust, structural deformation and airflow of six pairs of hummingbird-shaped membrane wings of different properties. The results show that for a specific spatial distribution of flexibility, there is an effective frequency range in thrust production. The wing deformation at the thrust-productive frequencies indicates the importance of flexibility: both bending and twisting motion can interact with aerodynamic loads to enhance wing performance under certain conditions, such as the deformation phase and amplitude. By measuring structural deformations under the same aerodynamic conditions, beneficial effects of passive wing deformation can be observed from the visualized airflow and averaged thrust. The measurements and their presentation enable observation and understanding of the required structural properties for a thrust effective flapping wing. The intended passive responses of the different wings follow a particular pattern in correlation to their aerodynamic performance. Consequently, both the experimental technique and data analysis method can lead to further studies to determine the design principles for micro air vehicle flapping wings.

  14. Structural dynamics and aerodynamics measurements of biologically inspired flexible flapping wings

    Energy Technology Data Exchange (ETDEWEB)

    Wu, P; Stanford, B K; Ifju, P G [Department of Mechanical and Aerospace Engineering, MAE-A 231, University of Florida, Gainesville, FL 32611 (United States); Saellstroem, E; Ukeiley, L, E-mail: diccidwp@ufl.edu [Department of Mechanical and Aerospace Engineering, University of Florida, Shalimar, FL 32579 (United States)

    2011-03-15

    Flapping wing flight as seen in hummingbirds and insects poses an interesting unsteady aerodynamic problem: coupling of wing kinematics, structural dynamics and aerodynamics. There have been numerous studies on the kinematics and aerodynamics in both experimental and computational cases with both natural and artificial wings. These studies tend to ignore wing flexibility; however, observation in nature affirms that passive wing deformation is predominant and may be crucial to the aerodynamic performance. This paper presents a multidisciplinary experimental endeavor in correlating a flapping micro air vehicle wing's aeroelasticity and thrust production, by quantifying and comparing overall thrust, structural deformation and airflow of six pairs of hummingbird-shaped membrane wings of different properties. The results show that for a specific spatial distribution of flexibility, there is an effective frequency range in thrust production. The wing deformation at the thrust-productive frequencies indicates the importance of flexibility: both bending and twisting motion can interact with aerodynamic loads to enhance wing performance under certain conditions, such as the deformation phase and amplitude. By measuring structural deformations under the same aerodynamic conditions, beneficial effects of passive wing deformation can be observed from the visualized airflow and averaged thrust. The measurements and their presentation enable observation and understanding of the required structural properties for a thrust effective flapping wing. The intended passive responses of the different wings follow a particular pattern in correlation to their aerodynamic performance. Consequently, both the experimental technique and data analysis method can lead to further studies to determine the design principles for micro air vehicle flapping wings.

  15. Wings of Stretched Metal

    Science.gov (United States)

    Nelken, Miranda

    2010-01-01

    This article presents a lesson that allows students to make bird ornaments using a metal tooling as it can be textured, cut, and colored. In this lesson, students choose a bird and sketch it on a piece of paper. Once the sketches are complete, students copy their pictures on a second piece of paper by taping the sketch over a sheet of blank paper…

  16. Color tejido

    OpenAIRE

    Rius Tormo, Palmira

    2010-01-01

    Póster presentado en el IX Congreso Nacional del Color, Alicante, 29-30 junio, 1-2 julio 2010. La exposición que se propone tiene como núcleo principal el color y muestra las posibilidades expresivas que aporta a los diferentes materiales. Las 7 obras presentadas buscan la armonía estética y la fuerza simbólica.

  17. Brilliant iridescence of Morpho butterfly wing scales is due to both a thin film lower lamina and a multilayered upper lamina

    NARCIS (Netherlands)

    Giraldo, M A; Stavenga, D G

    2016-01-01

    Butterflies belonging to the nymphalid subfamily, Morphinae, are famous for their brilliant blue wing coloration and iridescence. These striking optical phenomena are commonly explained as to originate from multilayer reflections by the ridges of the wing scales. Because the lower lamina of the

  18. Resilin-based rubber-like elastic elements in the insect wing: an overview

    Energy Technology Data Exchange (ETDEWEB)

    Gorb, S.N. [Max-Planck-Institut fuer Entwicklungsbiologie, Tuebingen (Germany)

    2000-07-01

    This report summarises data on the presence of resilin, a rubber-like protein in the flexibly-joined junctions of wing veins. This protein is a substance which is responsible for elastic energy storage. Previously this protein has been described in jumping systems of beetles, fleas and leafhoppers abdominal cuticle of workers of the honey-ants and queen termites; eye lens cuticle of dragonflies and the food-pump of reduviid bugs. It is also known in tendons of the dragonfly flight muscles. This protein has not been previously described in the distal regions of damselfly wings. The pattern of resilin distribution in the insect wings is one of several mechanisms which are responsible for automatic performance of passive wing movements. Any folding of the distal wing parts can not be achieved by local muscles, but must be done by remote (thoracic) muscles or local elasticity. Many insects, such as earwigs and beetles, have developed complex mechanisms of wing folding, which are advantagenous for insects living in soil or other narrow substrata. The folding pattern depends on the wing geometry, venation pattern, and material properties of structures involved. Thus design of wings with folding function has an additional complexity: their design is a kind of compromise between flight and folding. (orig.)

  19. Origin of Petrified Wood Color

    Directory of Open Access Journals (Sweden)

    George Mustoe

    2016-05-01

    Full Text Available Fossil forests have world-wide distribution, commonly preserving mineralized wood that displays vivid hues and complex color patterns. However, the origin of petrified color has received little scientific attention. Color of silicified wood may be influenced by the presence of relict organic matter, but the most significant contribution comes from trace metals. This study reports quantitative analysis of trace metals in 35 silicified wood samples, determined using LA-ICP-MS spectrometry. The most important of these metals is Fe, which can produce a rainbow of hues depending on its abundance and oxidation state. Cr is the dominant colorant for bright green fossil wood from Arizona, USA and Zimbabwe, Africa. Complex color patterns result from the progressive nature of the fossilization process, which causes wood to have varying degrees of permeability during successive episodes of permineralization. These processes include simple diffusion, chromatographic separation, infiltration of groundwater along fractures and void spaces, and oxidation/reduction.

  20. Color Charts, Esthetics, and Subjective Randomness

    Science.gov (United States)

    Sanderson, Yasmine B.

    2012-01-01

    Color charts, or grids of evenly spaced multicolored dots or squares, appear in the work of modern artists and designers. Often the artist/designer distributes the many colors in a way that could be described as "random," that is, without an obvious pattern. We conduct a statistical analysis of 125 "random-looking" art and design color charts and…

  1. Structural Analysis of a Dragonfly Wing

    NARCIS (Netherlands)

    Jongerius, S.R.; Lentink, D.

    2010-01-01

    Dragonfly wings are highly corrugated, which increases the stiffness and strength of the wing significantly, and results in a lightweight structure with good aerodynamic performance. How insect wings carry aerodynamic and inertial loads, and how the resonant frequency of the flapping wings is tuned

  2. Effect of outer wing separation on lift and thrust generation in a flapping wing system

    International Nuclear Information System (INIS)

    Mahardika, Nanang; Viet, Nguyen Quoc; Park, Hoon Cheol

    2011-01-01

    We explore the implementation of wing feather separation and lead-lagging motion to a flapping wing. A biomimetic flapping wing system with separated outer wings is designed and demonstrated. The artificial wing feather separation is implemented in the biomimetic wing by dividing the wing into inner and outer wings. The features of flapping, lead-lagging, and outer wing separation of the flapping wing system are captured by a high-speed camera for evaluation. The performance of the flapping wing system with separated outer wings is compared to that of a flapping wing system with closed outer wings in terms of forward force and downward force production. For a low flapping frequency ranging from 2.47 to 3.90 Hz, the proposed biomimetic flapping wing system shows a higher thrust and lift generation capability as demonstrated by a series of experiments. For 1.6 V application (lower frequency operation), the flapping wing system with separated wings could generate about 56% higher forward force and about 61% less downward force compared to that with closed wings, which is enough to demonstrate larger thrust and lift production capability of the separated outer wings. The experiments show that the outer parts of the separated wings are able to deform, resulting in a smaller amount of drag production during the upstroke, while still producing relatively greater lift and thrust during the downstroke.

  3. Single color and single flavor color superconductivity

    International Nuclear Information System (INIS)

    Alford, Mark G.; Cheyne, Jack M.; Cowan, Greig A.; Bowers, Jeffrey A.

    2003-01-01

    We survey the nonlocked color-flavor-spin channels for quark-quark (color superconducting) condensates in QCD, using a Nambu-Jona-Lasinio model. We also study isotropic quark-antiquark (mesonic) condensates. We make mean-field estimates of the strength and sign of the self-interaction of each condensate, using four-fermion interaction vertices based on known QCD interactions. For the attractive quark pairing channels, we solve the mean-field gap equations to obtain the size of the gap as a function of quark density. We also calculate the dispersion relations for the quasiquarks, in order to see how fully gapped the spectrum of fermionic excitations will be. We use our results to specify the likely pairing patterns in neutral quark matter, and comment on possible phenomenological consequences

  4. Flapping Wing Micro Air Vehicle Wing Manufacture and Force Testing

    Science.gov (United States)

    2011-03-03

    manufacturing techniques have been developed by various universities for research on Flapping Wing Micro Air Vehicles. Minimal attention though is given...collected at 2kHz (www.polytec.com/psv3d). A 0.25V band-limited white noise input signal is input to a Bogen HTA -125 High Performance Amplifier, which...manufacturing techniques have been developed by various universities for research on Flapping Wing Micro Air Vehicles. Minimal attention though is given

  5. Modeling human color categorization: Color discrimination and color memory

    NARCIS (Netherlands)

    Heskes, T.; van den Broek, Egon; Lucas, P.; Hendriks, Maria A.; Vuurpijl, L.G.; Puts, M.J.H.; Wiegerinck, W.

    2003-01-01

    Color matching in Content-Based Image Retrieval is done using a color space and measuring distances between colors. Such an approach yields non-intuitive results for the user. We introduce color categories (or focal colors), determine that they are valid, and use them in two experiments. The

  6. Research of Morphing Wing Efficiency

    National Research Council Canada - National Science Library

    Komarov, Valery

    2004-01-01

    This report results from a contract tasking Samara State Aerospace University (SSAU) as follows: The contractor will develop and investigate aerodynamic and structural weight theories associated with morphing wing technology...

  7. Extensive Rangewide Mitochondrial Introgression Indicates Substantial Cryptic Hybridization in the Golden-winged Warbler (Vermivora chrysoptera

    Directory of Open Access Journals (Sweden)

    Rachel Vallender

    2009-12-01

    Full Text Available Widespread population declines of the Golden-winged Warbler (Vermivora chrysoptera are thought to be due in part to hybridization with the expanding Blue-winged Warbler (V. pinus, which predictably replaces Golden-winged Warblers at breeding sites in which the two species come into contact. However, the mechanism by which this replacement occurs remains unresolved. Recent genetic work has indicated that, even in areas where the two species have been in contact for a short period, introgression of Blue-winged mitochondrial (mtDNA and nuclear genes into Golden-winged individuals is common. To explore this process on a broader scale, we screened more than 750 individuals from nine U.S. states and three provinces to examine geographic patterns of mtDNA introgression. The only population in which all phenotypic Golden-winged Warblers had Golden-winged mtDNA haplotypes, and in which there are no breeding Blue-winged or hybrid individuals, was in the province of Manitoba, near the northwestern edge of the species' breeding distribution. The near ubiquity of mitochondrial introgression suggests that there are far fewer genetically pure populations of Golden-winged Warblers than previously believed, a finding with important implications for this threatened species.

  8. DNATagger, colors for codons.

    Science.gov (United States)

    Scherer, N M; Basso, D M

    2008-09-16

    DNATagger is a web-based tool for coloring and editing DNA, RNA and protein sequences and alignments. It is dedicated to the visualization of protein coding sequences and also protein sequence alignments to facilitate the comprehension of evolutionary processes in sequence analysis. The distinctive feature of DNATagger is the use of codons as informative units for coloring DNA and RNA sequences. The codons are colored according to their corresponding amino acids. It is the first program that colors codons in DNA sequences without being affected by "out-of-frame" gaps of alignments. It can handle single gaps and gaps inside the triplets. The program also provides the possibility to edit the alignments and change color patterns and translation tables. DNATagger is a JavaScript application, following the W3C guidelines, designed to work on standards-compliant web browsers. It therefore requires no installation and is platform independent. The web-based DNATagger is available as free and open source software at http://www.inf.ufrgs.br/~dmbasso/dnatagger/.

  9. Experimental and computational study of transonic flow about swept wings

    Science.gov (United States)

    Bertelrud, A.; Bergmann, M. Y.; Coakley, T. J.

    1980-01-01

    An experimental investigation of NACA 0010 and 10% circular arc wing models, swept at 45 deg, spanning a channel, and at zero angle of attack is described. Measurements include chordwise and spanwise surface pressure distributions and oil-flow patterns for a range of transonic Mach numbers and Reynolds numbers. Calculations using a new three-dimensional Navier-Stokes code and a two-equation turbulence model are included for the circular-arc wing flow. Reasonable agreement between measurements and computations is obtained.

  10. Color superconductivity

    Energy Technology Data Exchange (ETDEWEB)

    Wilczek, F. [Institute for Advanced Study, Princeton, NJ (United States)

    1997-09-22

    The asymptotic freedom of QCD suggests that at high density - where one forms a Fermi surface at very high momenta - weak coupling methods apply. These methods suggest that chiral symmetry is restored and that an instability toward color triplet condensation (color superconductivity) sets in. Here I attempt, using variational methods, to estimate these effects more precisely. Highlights include demonstration of a negative pressure in the uniform density chiral broken phase for any non-zero condensation, which we take as evidence for the philosophy of the MIT bag model; and demonstration that the color gap is substantial - several tens of MeV - even at modest densities. Since the superconductivity is in a pseudoscalar channel, parity is spontaneously broken.

  11. Anopheles darlingi (Diptera: Culicidae Rood 1926: Morphometric variations in wings and legs of populations from Colombia

    Directory of Open Access Journals (Sweden)

    Miguel Alfonso Pacheco

    2017-03-01

    Conclusions. We registered 11 new wing spot patterns in the costal vein and the dominance of the patterns I and VI for populations of An. darlingi from Colombia. We confirmed DSIII2/TaIII2 ratio as a robust diagnostic character for the taxonomy of this species. We found differences between the size and shape of the wings of An. darlingi populations in accordance to their geographical distribution, which constitute important bionomic aspects for this malaria vector.

  12. Object color affects identification and repetition priming.

    Science.gov (United States)

    Uttl, Bob; Graf, Peter; Santacruz, Pilar

    2006-10-01

    We investigated the influence of color on the identification of both non-studied and studied objects. Participants studied black and white and color photos of common objects and memory was assessed with an identification test. Consistent with our meta-analysis of prior research, we found that objects were easier to identify from color than from black and white photos. We also found substantial priming in all conditions, and study-to-test changes in an object's color reduced the magnitude of priming. Color-specific priming effects were large for color-complex objects, but minimal for color-simple objects. The pattern and magnitude of priming effects was not influenced either by the extent to which an object always appears in the same color (i.e., whether a color is symptomatic of an object) or by the object's origin (natural versus fabricated). We discuss the implications of our findings for theoretical accounts of object perception and repetition priming.

  13. Sexually Dimorphic Body Color Is Regulated by Sex-Specific Expression of Yellow Gene in Ponerine Ant, Diacamma Sp

    Science.gov (United States)

    Miyazaki, Satoshi; Okada, Yasukazu; Miyakawa, Hitoshi; Tokuda, Gaku; Cornette, Richard; Koshikawa, Shigeyuki; Maekawa, Kiyoto; Miura, Toru

    2014-01-01

    Most hymenopteran species exhibit conspicuous sexual dimorphism due to ecological differences between the sexes. As hymenopteran genomes, under the haplodiploid genetic system, exhibit quantitative differences between sexes while remaining qualitatively identical, sexual phenotypes are assumed to be expressed through sex-specific gene usage. In the present study, the molecular basis for expression of sexual dimorphism in a queenless ant, Diacamma sp., which exhibits a distinct color dimorphism, was examined. Worker females of the species appear bluish-black, while winged males exhibit a yellowish-brown body color. Initially, observations of the pigmentation processes during pupal development revealed that black pigmentation was present in female pupae but not in males, suggesting that sex-specific melanin synthesis was responsible for the observed color dimorphism. Therefore, five orthologs of the genes involved in the insect melanin synthesis (yellow, ebony, tan, pale and dopa decarboxylase) were subcloned and their spatiotemporal expression patterns were examined using real-time quantitative RT-PCR. Of the genes examined, yellow, which plays a role in black melanin synthesis in insects, was expressed at higher levels in females than in males throughout the entire body during the pupal stage. RNA interference of yellow was then carried out in order to determine the gene function, and produced females with a more yellowish, brighter body color similar to that of males. It was concluded that transcriptional regulation of yellow was responsible for the sexual color dimorphism observed in this species. PMID:24667821

  14. Sexually dimorphic body color is regulated by sex-specific expression of yellow gene in ponerine ant, Diacamma sp.

    Directory of Open Access Journals (Sweden)

    Satoshi Miyazaki

    Full Text Available Most hymenopteran species exhibit conspicuous sexual dimorphism due to ecological differences between the sexes. As hymenopteran genomes, under the haplodiploid genetic system, exhibit quantitative differences between sexes while remaining qualitatively identical, sexual phenotypes are assumed to be expressed through sex-specific gene usage. In the present study, the molecular basis for expression of sexual dimorphism in a queenless ant, Diacamma sp., which exhibits a distinct color dimorphism, was examined. Worker females of the species appear bluish-black, while winged males exhibit a yellowish-brown body color. Initially, observations of the pigmentation processes during pupal development revealed that black pigmentation was present in female pupae but not in males, suggesting that sex-specific melanin synthesis was responsible for the observed color dimorphism. Therefore, five orthologs of the genes involved in the insect melanin synthesis (yellow, ebony, tan, pale and dopa decarboxylase were subcloned and their spatiotemporal expression patterns were examined using real-time quantitative RT-PCR. Of the genes examined, yellow, which plays a role in black melanin synthesis in insects, was expressed at higher levels in females than in males throughout the entire body during the pupal stage. RNA interference of yellow was then carried out in order to determine the gene function, and produced females with a more yellowish, brighter body color similar to that of males. It was concluded that transcriptional regulation of yellow was responsible for the sexual color dimorphism observed in this species.

  15. Effects of external influences in subsonic delta wing vortices

    Science.gov (United States)

    Washburn, Anthony E.

    1992-01-01

    An experimental investigation was conducted to examine inconsistencies in reported studies for the vortical flow over highly-swept delta wings. A 76-deg swept delta wing was tested in three facilities with open and closed test sections and different model-support systems. The results obtained include surface oil-flow patterns, off-body laser-light-sheet flow visualization, and aerodynamic load measurements. Parameters such as the wall boundaries and model-support systems can drastically alter the loads. The effect of a high level of free-stream turbulence on the delta-wing flowfield was also examined and found to be significant. The increase in free-stream turbulence caused boundary-layer transition, unsteadiness in the vortex core positions, and altered the loads and moments.

  16. Shape matters: improved flight in tapered auto-rotating wings

    Science.gov (United States)

    Liu, Yucen; Vincent, Lionel; Kanso, Eva

    2017-11-01

    Many plants use gravity and wind to disperse their seeds. The shape of seed pods influence their aerodynamics. For example, Liana seeds form aerodynamic gliders and Sycamore trees release airborne ``helicopters.'' Here, we use carefully-controlled experiments and high-speed photography to examine dispersion by tumbling (auto-rotation) and we focus on the effect of geometry on flight characteristics. We consider four families of shapes: rectangular, elliptic, tapered, and sharp-tip wings, and we vary the span-to-chord ratio. We find that tapered wings exhibit extended flight time and range, that is, better performance. A quasi-steady two-dimensional model is used to highlight the mechanisms by which shape affects flight performance. These findings could have significant implications on linking seedpod designs to seed dispersion patterns as well as on optimizing wing design in active flight problems.

  17. Comparación de la morfología alar de Tadarida brasiliensis (Chiroptera: Molossidae y Myotis chiloensis (Chiroptera: Vespertilionidae, representantes de dos diferentes patrones de vuelo Comparison of the wing morphology of Tadarida brasiliensis (Chiroptera: Molossidae and Myotis chiloensis (Chiroptera: Vespertilionidae as representatives of two flight patterns

    Directory of Open Access Journals (Sweden)

    MAURICIO CANALS

    2001-09-01

    Full Text Available La morfología alar de los quirópteros se encuentra relacionada por una parte con la biomecánica y energética del vuelo y por otra parte con aspectos ecológicos y conductuales (i.e., patrón de vuelo, conducta de forrajeo y selección de hábitat y de presas. En este trabajo se compara la morfometría alar de Tadarida brasiliensis (Molossidae y Myotis chiloensis (Vespertilionidae, representantes de diferentes patrones de vuelo, buscando compromisos entre la morfometría alar y aspectos ecológicos y conductuales. Nuestros resultados muestran que T. brasiliensis es un murciélago más robusto, de mayor envergadura, pero con un área alar similar a la de M. chiloensis. Esta última especie tiene una menor variabilidad en su masa y área cortical del húmero, que probablemente se encuentre relacionada con restricciones mecánicas y energéticas impuestas por su diseño. Descontando el efecto de la masa se detectaron diferencias en el diámetro externo y diámetro medular del húmero con una similar área cortical. El húmero de T. brasiliensis es un hueso de similar longitud, más ancho y con un menor grosor cortical que el de M. chiloensis, lo que está relacionado con una mayor resistencia a las fuerzas de flexión y torsión. Las características alares son consistentes con los modos de vida de cada murciélago: vuelos lentos, cortos y maniobrables en zonas arbustivas de M. chiloensis y vuelo veloz y de grandes distancias en espacios abiertos de T. brasiliensisWing morphology is related by one hand to biomechanical properties and energetics of flying, and on the other hand to ecological and behavioral aspects of flying, such as flight pattern, foraging behavior, habitat selection and size of prey. In this work we compare the wing morphology of Tadarida brasiliensis (Molossidae and Myotis chiloensis (Vespertilionidae, as representatives of two flight patterns, and looking for trade-offs between wing morphology, ecology and behavior. Our

  18. Cave microbial community composition in oceanic islands: disentangling the effect of different colored mats in diversity patterns of Azorean lava caves.

    Science.gov (United States)

    Riquelme, Cristina; Rigal, François; Hathaway, Jennifer J M; Northup, Diana E; Spilde, Michael N; Borges, Paulo A V; Gabriel, Rosalina; Amorim, Isabel R; Dapkevicius, Maria de Lurdes N E

    2015-12-01

    Processes determining diversity and composition of bacterial communities in island volcanic caves are still poorly understood. Here, we characterized colored microbial mats in 14 volcanic caves from two oceanic islands of the Azores using 16S rRNA gene sequences. Factors determining community diversity (α) and composition (β) were explored, namely colored mats, caves and islands, as well as environmental and chemical characteristics of caves. Additive partitioning of diversity using OTU occurrence showed a greater influence of β-diversity between islands and caves that may relate to differences in rare OTUs (singletons and doubletons) across scales. In contrast, Shannon diversity partitioning revealed the importance of the lowest hierarchical level (α diversity, colored mat), suggesting a dominance of cosmopolitan OTUs (>1%) in most samples. Cosmopolitan OTUs included members involved in nitrogen cycling, supporting the importance of this process in Azorean caves. Environmental and chemical conditions in caves did not show any significant relationship to OTU diversity and composition. The absence of clear differences between mat colors and across scales may be explained by (1) the geological youth of the cave system (cave communities have not had enough time to diverge) or/and (2) community convergence, as the result of selection pressure in extreme environments. © FEMS 2015. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  19. Imaging optical scattering of butterfly wing scales with a microscope.

    Science.gov (United States)

    Fu, Jinxin; Yoon, Beom-Jin; Park, Jung Ok; Srinivasarao, Mohan

    2017-08-06

    A new optical method is proposed to investigate the reflectance of structurally coloured objects, such as Morpho butterfly wing scales and cholesteric liquid crystals. Using a reflected-light microscope and a digital single-lens reflex (DSLR) camera, we have successfully measured the two-dimensional reflection pattern of individual wing scales of Morpho butterflies. We demonstrate that this method enables us to measure the bidirectional reflectance distribution function (BRDF). The scattering image observed in the back focal plane of the objective is projected onto the camera sensor by inserting a Bertrand lens in the optical path of the microscope. With monochromatic light illumination, we quantify the angle-dependent reflectance spectra from the wing scales of Morpho rhetenor by retrieving the raw signal from the digital camera sensor. We also demonstrate that the polarization-dependent reflection of individual wing scales is readily observed using this method, using the individual wing scales of Morpho cypris . In an effort to show the generality of the method, we used a chiral nematic fluid to illustrate the angle-dependent reflectance as seen by this method.

  20. Color Sense

    Science.gov (United States)

    Johnson, Heidi S. S.; Maki, Jennifer A.

    2009-01-01

    This article reports a study conducted by members of the WellU Academic Integration Subcommittee of The College of St. Scholastica's College's Healthy Campus Initiative plan whose purpose was to determine whether changing color in the classroom could have a measurable effect on students. One simple improvement a school can make in a classroom is…

  1. Waterproof and translucent wings at the same time: problems and solutions in butterflies

    Science.gov (United States)

    Perez Goodwyn, Pablo; Maezono, Yasunori; Hosoda, Naoe; Fujisaki, Kenji

    2009-07-01

    Although the colour of butterflies attracts the most attention, the waterproofing properties of their wings are also extremely interesting. Most butterfly wings are considered “super-hydrophobic” because the contact angle (CA) with a water drop exceeds 150°. Usually, butterfly wings are covered with strongly overlapping scales; however, in the case of transparent or translucent wings, scale cover is reduced; thus, the hydrophobicity could be affected. Here, we present a comparative analysis of wing hydrophobicity and its dependence on morphology for two species with translucent wings Parantica sita (Nymphalidae) and Parnassius glacialis (Papilionidae). These species have very different life histories: P. sita lives for up to 6 months as an adult and migrates over long distance, whereas P. glacialis lives for less than 1 month and does not migrate. We measured the water CA and analysed wing morphology with scanning electron microscopy and atomic force microscopy. P. sita has super-hydrophobic wing surfaces, with CA > 160°, whereas P. glacialis did not (CA = 100-135°). Specialised scales were found on the translucent portions of P. sita wings. These scales were ovoid and much thinner than common scales, erect at about 30°, and leaving up to 80% of the wing surface uncovered. The underlying bare wing surface had a remarkable pattern of ridges and knobs. P. glacialis also had over 80% of the wing surface uncovered, but the scales were either setae-like or spade-like. The bare surface of the wing had an irregular wavy smooth pattern. We suggest a mode of action that allows this super-hydrophobic effect with an incompletely covered wing surface. The scales bend, but do not collapse, under the pressure of a water droplet, and the elastic recovery of the structure at the borders of the droplet allows a high apparent CA. Thus, P. sita can be translucent without losing its waterproof properties. This characteristic is likely necessary for the long life and migration

  2. Mapping alpine soils using color positive and color infrared photographs

    Science.gov (United States)

    Burns, S.

    1980-01-01

    During a soil survey of the Indian Peaks area of the Colorado Front Range, it was found that large scale color positive photographs taken in the autumn were extremely useful for mapping alpine soils. Smaller scale color infrared photos were also helpful for delineation of mapping units. The soil mapping units were deduced on the basis of landforms and snow accumulation which is reflected in patterns of vegetational communities.

  3. Fear no colors? Observer clothing color influences lizard escape behavior.

    Science.gov (United States)

    Putman, Breanna J; Drury, Jonathan P; Blumstein, Daniel T; Pauly, Gregory B

    2017-01-01

    Animals often view humans as predators, leading to alterations in their behavior. Even nuanced aspects of human activity like clothing color affect animal behavior, but we lack an understanding of when and where such effects will occur. The species confidence hypothesis posits that birds are attracted to colors found on their bodies and repelled by non-body colors. Here, we extend this hypothesis taxonomically and conceptually to test whether this pattern is applicable in a non-avian reptile and to suggest that species should respond less fearfully to their sexually-selected signaling color. Responses to clothing color could also be impacted by habituation to humans, so we examine whether behavior varied between areas with low and high human activity. We quantified the effects of four T-shirt colors on flight initiation distances (FID) and on the ease of capture in western fence lizards (Sceloporus occidentalis), and we accounted for detectability against the background environment. We found no differences in lizard behavior between sites. However, lizards tolerated the closest approaches and were most likely to be captured when approached with the T-shirt that resembled their sexually-selected signaling color. Because changes in individual behavior affect fitness, choice of clothing color by people, including tourists, hikers, and researchers, could impact wildlife populations and research outcomes.

  4. Fear no colors? Observer clothing color influences lizard escape behavior.

    Directory of Open Access Journals (Sweden)

    Breanna J Putman

    Full Text Available Animals often view humans as predators, leading to alterations in their behavior. Even nuanced aspects of human activity like clothing color affect animal behavior, but we lack an understanding of when and where such effects will occur. The species confidence hypothesis posits that birds are attracted to colors found on their bodies and repelled by non-body colors. Here, we extend this hypothesis taxonomically and conceptually to test whether this pattern is applicable in a non-avian reptile and to suggest that species should respond less fearfully to their sexually-selected signaling color. Responses to clothing color could also be impacted by habituation to humans, so we examine whether behavior varied between areas with low and high human activity. We quantified the effects of four T-shirt colors on flight initiation distances (FID and on the ease of capture in western fence lizards (Sceloporus occidentalis, and we accounted for detectability against the background environment. We found no differences in lizard behavior between sites. However, lizards tolerated the closest approaches and were most likely to be captured when approached with the T-shirt that resembled their sexually-selected signaling color. Because changes in individual behavior affect fitness, choice of clothing color by people, including tourists, hikers, and researchers, could impact wildlife populations and research outcomes.

  5. Colorful solar selective absorber integrated with different colored units.

    Science.gov (United States)

    Chen, Feiliang; Wang, Shao-Wei; Liu, Xingxing; Ji, Ruonan; Li, Zhifeng; Chen, Xiaoshuang; Chen, Yuwei; Lu, Wei

    2016-01-25

    Solar selective absorbers are the core part for solar thermal technologies such as solar water heaters, concentrated solar power, solar thermoelectric generators and solar thermophotovoltaics. Colorful solar selective absorber can provide new freedom and flexibility beyond energy performance, which will lead to wider utilization of solar technologies. In this work, we present a monolithic integration of colored solar absorber array with different colors on a single substrate based on a multilayered structure of Cu/TiN(x)O(y)/TiO(2)/Si(3)N(4)/SiO(2). A colored solar absorber array with 16 color units is demonstrated experimentally by using combinatorial deposition technique via changing the thickness of SiO(2) layer. The solar absorptivity and thermal emissivity of all the color units is higher than 92% and lower than 5.5%, respectively. The colored solar selective absorber array can have colorful appearance and designable patterns while keeping high energy performance at the same time. It is a new candidate for a number of solar applications, especially for architecture integration and military camouflage.

  6. Color naming across languages reflects color use.

    Science.gov (United States)

    Gibson, Edward; Futrell, Richard; Jara-Ettinger, Julian; Mahowald, Kyle; Bergen, Leon; Ratnasingam, Sivalogeswaran; Gibson, Mitchell; Piantadosi, Steven T; Conway, Bevil R

    2017-10-03

    What determines how languages categorize colors? We analyzed results of the World Color Survey (WCS) of 110 languages to show that despite gross differences across languages, communication of chromatic chips is always better for warm colors (yellows/reds) than cool colors (blues/greens). We present an analysis of color statistics in a large databank of natural images curated by human observers for salient objects and show that objects tend to have warm rather than cool colors. These results suggest that the cross-linguistic similarity in color-naming efficiency reflects colors of universal usefulness and provide an account of a principle (color use) that governs how color categories come about. We show that potential methodological issues with the WCS do not corrupt information-theoretic analyses, by collecting original data using two extreme versions of the color-naming task, in three groups: the Tsimane', a remote Amazonian hunter-gatherer isolate; Bolivian-Spanish speakers; and English speakers. These data also enabled us to test another prediction of the color-usefulness hypothesis: that differences in color categorization between languages are caused by differences in overall usefulness of color to a culture. In support, we found that color naming among Tsimane' had relatively low communicative efficiency, and the Tsimane' were less likely to use color terms when describing familiar objects. Color-naming among Tsimane' was boosted when naming artificially colored objects compared with natural objects, suggesting that industrialization promotes color usefulness.

  7. Patterns of phenotypic plasticity in common and rare environments: a study of host use and color learning in the cabbage white butterfly Pieris rapae.

    Science.gov (United States)

    Snell-Rood, Emilie C; Papaj, Daniel R

    2009-05-01

    Phenotypic plasticity is adaptive in variable environments but, given its costs, may be disfavored if only one environment is commonly encountered. Yet species in relatively constant environments often adjust phenotypes successfully in rare or novel environments. Developmental biases may reduce the costs of plasticity in common environments, favoring the maintenance of plasticity. We explored this proposition by studying the flexibility of visually guided host-selection behavior in cabbage white butterflies (Pieris rapae), wherein common and rare environments consisted of green and red host types, respectively. We demonstrated in greenhouse assays that adult females display an innate bias toward green color during host search but alter that bias through learning in red-host assemblages such that, after several hours of experience, red hosts are located as efficiently as green hosts. Full-sib analyses suggested there was genetic variation in host and color choice that was more pronounced in the red-host environment. We found no evidence of genetic correlations in behavior across host environments or of fitness costs of plasticity in color choice. Our results support the idea that learning may persist in less variable environments through the evolution of innate biases that reduce operating costs in common environments.

  8. The Efficiency of a Hybrid Flapping Wing Structure—A Theoretical Model Experimentally Verified

    Directory of Open Access Journals (Sweden)

    Yuval Keren

    2016-07-01

    Full Text Available To propel a lightweight structure, a hybrid wing structure was designed; the wing’s geometry resembled a rotor blade, and its flexibility resembled an insect’s flapping wing. The wing was designed to be flexible in twist and spanwise rigid, thus maintaining the aeroelastic advantages of a flexible wing. The use of a relatively “thick” airfoil enabled the achievement of higher strength to weight ratio by increasing the wing’s moment of inertia. The optimal design was based on a simplified quasi-steady inviscid mathematical model that approximately resembles the aerodynamic and inertial behavior of the flapping wing. A flapping mechanism that imitates the insects’ flapping pattern was designed and manufactured, and a set of experiments for various parameters was performed. The simplified analytical model was updated according to the tests results, compensating for the viscid increase of drag and decrease of lift, that were neglected in the simplified calculations. The propelling efficiency of the hovering wing at various design parameters was calculated using the updated model. It was further validated by testing a smaller wing flapping at a higher frequency. Good and consistent test results were obtained in line with the updated model, yielding a simple, yet accurate tool, for flapping wings design.

  9. Colored Contact Lens Dangers

    Medline Plus

    Full Text Available ... One Use Facts About Colored Contacts and Halloween Safety Colored Contact Lens Facts Over-the-Counter Costume ... use of colored contact lenses , from the U.S. Food and Drug Administration (FDA). Are the colored lenses ...

  10. Conceptual Study of Rotary-Wing Microrobotics

    National Research Council Canada - National Science Library

    Chabak, Kelson D

    2008-01-01

    This thesis presents a novel rotary-wing micro-electro-mechanical systems (MEMS) robot design. Two MEMS wing designs were designed, fabricated and tested including one that possesses features conducive to insect level aerodynamics...

  11. Aerodynamic control with passively pitching wings

    Science.gov (United States)

    Gravish, Nick; Wood, Robert

    Flapping wings may pitch passively under aerodynamic and inertial loads. Such passive pitching is observed in flapping wing insect and robot flight. The effect of passive wing pitch on the control dynamics of flapping wing flight are unexplored. Here we demonstrate in simulation and experiment the critical role wing pitching plays in yaw control of a flapping wing robot. We study yaw torque generation by a flapping wing allowed to passively rotate in the pitch axis through a rotational spring. Yaw torque is generated through alternating fast and slow upstroke and and downstroke. Yaw torque sensitively depends on both the rotational spring force law and spring stiffness, and at a critical spring stiffness a bifurcation in the yaw torque control relationship occurs. Simulation and experiment reveal the dynamics of this bifurcation and demonstrate that anomalous yaw torque from passively pitching wings is the result of aerodynamic and inertial coupling between the pitching and stroke-plane dynamics.

  12. Lithographically-generated 3D lamella layers and their structural color

    Science.gov (United States)

    Zhang, Sichao; Chen, Yifang; Lu, Bingrui; Liu, Jianpeng; Shao, Jinhai; Xu, Chen

    2016-04-01

    Inspired by the structural color from the multilayer nanophotonic structures in Morpho butterfly wing scales, 3D lamellae layers in dielectric polymers (polymethyl methacrylate, PMMA) with n ~ 1.5 were designed and fabricated by standard top-down electron beam lithography with one-step exposure followed by an alternating development/dissolution process of PMMA/LOR (lift-off resist) multilayers. This work offers direct proof of the structural blue/green color via lithographically-replicated PMMA/air multilayers, analogous to those in real Morpho butterfly wings. The success of nanolithography in this work for the 3D lamellae structures in dielectric polymers not only enables us to gain deeper insight into the mysterious blue color of the Morpho butterfly wings, but also breaks through the bottleneck in technical development toward broad applications in gas/liquid sensors, 3D meta-materials, coloring media, and infrared imaging devices, etc.

  13. Wind tunnel investigation of the interaction and breakdown characteristics of slender wing vortices at subsonic, transonic, and supersonic speeds

    Science.gov (United States)

    Erickson, Gary E.

    1991-01-01

    The vortex dominated aerodynamic characteristics of a generic 65 degree cropped delta wing model were studied in a wind tunnel at subsonic through supersonic speeds. The lee-side flow fields over the wing-alone configuration and the wing with leading edge extension (LEX) added were observed at M (infinity) equals 0.40 to 1.60 using a laser vapor screen technique. These results were correlated with surface streamline patterns, upper surface static pressure distributions, and six-component forces and moments. The wing-alone exhibited vortex breakdown and asymmetry of the breakdown location at the subsonic and transonic speeds. An earlier onset of vortex breakdown over the wing occurred at transonic speeds due to the interaction of the leading edge vortex with the normal shock wave. The development of a shock wave between the vortex and wing surface caused an early separation of the secondary boundary layer. With the LEX installed, wing vortex breakdown asymmetry did not occur up to the maximum angle of attack in the present test of 24 degrees. The favorable interaction of the LEX vortex with the wing flow field reduced the effects of shock waves on the wing primary and secondary vortical flows. The direct interaction of the wing and LEX vortex cores diminished with increasing Mach number. The maximum attainable vortex-induced pressure signatures were constrained by the vacuum pressure limit at the transonic and supersonic speeds.

  14. Waving Wing Aerodynamics at Low Reynolds Numbers

    Science.gov (United States)

    2010-07-01

    wing. An attached leading edge vortex has been observed by multiple research groups on both mechanical wing flappers (8; 22; 21; 4) and revolving wing...observed by Ellington et al. (8) in their earlier experiments on the mechanical hawkmoth flapper at Re ≈ 10,000. In these experiments the spanwise flow...on mechanical wing flappers at similar Reynolds numbers, Re ≈ 1,000 and 1,400 respectively. Both sets of experiments revealed a stable attached

  15. Cellular basis of morphological variation and temperature-related plasticity in Drosophila melanogaster strains with divergent wing shapes.

    Science.gov (United States)

    Torquato, Libéria Souza; Mattos, Daniel; Matta, Bruna Palma; Bitner-Mathé, Blanche Christine

    2014-12-01

    Organ shape evolves through cross-generational changes in developmental patterns at cellular and/or tissue levels that ultimately alter tissue dimensions and final adult proportions. Here, we investigated the cellular basis of an artificially selected divergence in the outline shape of Drosophila melanogaster wings, by comparing flies with elongated or rounded wing shapes but with remarkably similar wing sizes. We also tested whether cellular plasticity in response to developmental temperature was altered by such selection. Results show that variation in cellular traits is associated with wing shape differences, and that cell number may play an important role in wing shape response to selection. Regarding the effects of developmental temperature, a size-related plastic response was observed, in that flies reared at 16 °C developed larger wings with larger and more numerous cells across all intervein regions relative to flies reared at 25 °C. Nevertheless, no conclusive indication of altered phenotypic plasticity was found between selection strains for any wing or cellular trait. We also described how cell area is distributed across different intervein regions. It follows that cell area tends to decrease along the anterior wing compartment and increase along the posterior one. Remarkably, such pattern was observed not only in the selected strains but also in the natural baseline population, suggesting that it might be canalized during development and was not altered by the intense program of artificial selection for divergent wing shapes.

  16. Variable wing venation in Agathiphaga (Lepidoptera: Agathiphagidae) is key to understanding the evolution of basal moths

    Science.gov (United States)

    Gibbs, George W.

    2016-01-01

    Details of the ancestral groundplan of wing venation in moths remain uncertain, despite approximately a century of study. Here, we describe a 3-branched subcostal vein, a 5-branched medial vein and a 2-branched cubitus posterior vein on the forewing of Agathiphaga vitiensis Dumbleton 1952 from Vanuatu. Such veins had not previously been described in any Lepidoptera. Because wing veins are typically lost during lepidopteran evolutionary history, rarely—if ever—to be regained, the venation of A. vitiensis probably represents the ancestral character state for moths. Wing venation is often used to identify fossil insects as moths, because wing scales are not always preserved; the presence of a supposedly trichopteran 3-branched subcostal vein in crown Lepidoptera may decrease the certainty with which certain amphiesmenopteran fossils from the Mesozoic can be classified. And because plesiomorphic veins can influence the development of lepidopteran wing patterns even if not expressed in the adult wing, the veins described here may determine the location of wing pattern elements in many lepidopteran taxa. PMID:27853559

  17. Aerodynamic forces and flow structures of the leading edge vortex on a flapping wing considering ground effect

    International Nuclear Information System (INIS)

    Truong, Tien Van; Yoon, Kwang Joon; Byun, Doyoung; Kim, Min Jun; Park, Hoon Cheol

    2013-01-01

    The aim of this work is to provide an insight into the aerodynamic performance of the beetle during takeoff, which has been estimated in previous investigations. We employed a scaled-up electromechanical model flapping wing to measure the aerodynamic forces and the three-dimensional flow structures on the flapping wing. The ground effect on the unsteady forces and flow structures were also characterized. The dynamically scaled wing model could replicate the general stroke pattern of the beetle's hind wing kinematics during takeoff flight. Two wing kinematic models have been studied to examine the influences of wing kinematics on unsteady aerodynamic forces. In the first model, the angle of attack is asymmetric and varies during the translational motion, which is the flapping motion of the beetle's hind wing. In the second model, the angle of attack is constant during the translational motion. The instantaneous aerodynamic forces were measured for four strokes during the beetle's takeoff by the force sensor attached at the wing base. Flow visualization provided a general picture of the evolution of the three-dimensional leading edge vortex (LEV) on the beetle hind wing model. The LEV is stable during each stroke, and increases radically from the root to the tip, forming a leading-edge spiral vortex. The force measurement results show that the vertical force generated by the hind wing is large enough to lift the beetle. For the beetle hind wing kinematics, the total vertical force production increases 18.4% and 8.6% for the first and second strokes, respectively, due to the ground effect. However, for the model with a constant angle of attack during translation, the vertical force is reduced during the first stroke. During the third and fourth strokes, the ground effect is negligible for both wing kinematic patterns. This finding suggests that the beetle's flapping mechanism induces a ground effect that can efficiently lift its body from the ground during takeoff

  18. Aerodynamic forces and flow structures of the leading edge vortex on a flapping wing considering ground effect.

    Science.gov (United States)

    Van Truong, Tien; Byun, Doyoung; Kim, Min Jun; Yoon, Kwang Joon; Park, Hoon Cheol

    2013-09-01

    The aim of this work is to provide an insight into the aerodynamic performance of the beetle during takeoff, which has been estimated in previous investigations. We employed a scaled-up electromechanical model flapping wing to measure the aerodynamic forces and the three-dimensional flow structures on the flapping wing. The ground effect on the unsteady forces and flow structures were also characterized. The dynamically scaled wing model could replicate the general stroke pattern of the beetle's hind wing kinematics during takeoff flight. Two wing kinematic models have been studied to examine the influences of wing kinematics on unsteady aerodynamic forces. In the first model, the angle of attack is asymmetric and varies during the translational motion, which is the flapping motion of the beetle's hind wing. In the second model, the angle of attack is constant during the translational motion. The instantaneous aerodynamic forces were measured for four strokes during the beetle's takeoff by the force sensor attached at the wing base. Flow visualization provided a general picture of the evolution of the three-dimensional leading edge vortex (LEV) on the beetle hind wing model. The LEV is stable during each stroke, and increases radically from the root to the tip, forming a leading-edge spiral vortex. The force measurement results show that the vertical force generated by the hind wing is large enough to lift the beetle. For the beetle hind wing kinematics, the total vertical force production increases 18.4% and 8.6% for the first and second strokes, respectively, due to the ground effect. However, for the model with a constant angle of attack during translation, the vertical force is reduced during the first stroke. During the third and fourth strokes, the ground effect is negligible for both wing kinematic patterns. This finding suggests that the beetle's flapping mechanism induces a ground effect that can efficiently lift its body from the ground during takeoff.

  19. Wing area, wing growth and wing loading of common sandpipers Actitis hypoleucos

    OpenAIRE

    Yalden, Derek; Yalden, D. W.

    2012-01-01

    This study investigates the changes in wing length, area and loading in Common Sandpipers as chicks grow, and as adults add extra mass (during egg-laying or before migration). Common Sandpiper chicks weigh about 17 g and have "hands" that are about 35 mm long at one week old, when the primaries are just emerging from their sheaths. They grow steadily to reach about 40 g, with hands about 85 mm long, at 19 days, when they are just about fledging. Their wings have roughly adult chord width at t...

  20. Focal colors across languages are representative members of color categories.

    Science.gov (United States)

    Abbott, Joshua T; Griffiths, Thomas L; Regier, Terry

    2016-10-04

    Focal colors, or best examples of color terms, have traditionally been viewed as either the underlying source of cross-language color-naming universals or derived from category boundaries that vary widely across languages. Existing data partially support and partially challenge each of these views. Here, we advance a position that synthesizes aspects of these two traditionally opposed positions and accounts for existing data. We do so by linking this debate to more general principles. We show that best examples of named color categories across 112 languages are well-predicted from category extensions by a statistical model of how representative a sample is of a distribution, independently shown to account for patterns of human inference. This model accounts for both universal tendencies and variation in focal colors across languages. We conclude that categorization in the contested semantic domain of color may be governed by principles that apply more broadly in cognition and that these principles clarify the interplay of universal and language-specific forces in color naming.

  1. Bioinspired Heterogeneous Structural Color Stripes from Capillaries.

    Science.gov (United States)

    Zhao, Ze; Wang, Huan; Shang, Luoran; Yu, Yunru; Fu, Fanfan; Zhao, Yuanjin; Gu, Zhongze

    2017-12-01

    As an important characteristic of many creatures, structural colors play a crucial role in the survival of organisms. Inspired by these features, an intelligent structural color material with a heterogeneous striped pattern and stimuli-responsivity by fast self-assembly of colloidal nanoparticles in capillaries with a certain diameter range are presented here. The width, spacing, color, and even combination of the structural color stripe patterns can be precisely tailored by adjusting the self-assembly parameters. Attractively, with the integration of a near-infrared (NIR) light responsive graphene hydrogel into the structural color stripe pattern, the materials are endowed with light-controlled reversible bending behavior with self-reporting color indication. It is demonstrated that the striped structural color materials can be used as NIR-light-triggered dynamic barcode labels for the anti-counterfeiting of different products. These features of the bioinspired structural color stripe pattern materials indicate their potential values for mimicking structural color organisms, which will find important applications in constructing intelligent sensors, anti-counterfeiting devices, and so on. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  2. How Do Wings Generate Lift?

    Indian Academy of Sciences (India)

    Newton's second law of motion. Hence if a wing can generate lift equal to its weight (total weight of the vehicle) it can balance the gravitational pull and can maintain level flight. The equations for fluid flow that are equivalent to the second law are the well- known Navier–Stokes (N–S) equations [1]. These equations have.

  3. Werner helicase wings DNA binding

    OpenAIRE

    Hoadley, Kelly A.; Keck, James L.

    2010-01-01

    In this issue of Structure, Kitano et al. describe the structure of the DNA-bound winged-helix domain from the Werner helicase. This structure of a RecQ/DNA complex offers insights into the DNA unwinding mechanisms of RecQ family helicases.

  4. On Wings: Aerodynamics of Eagles.

    Science.gov (United States)

    Millson, David

    2000-01-01

    The Aerodynamics Wing Curriculum is a high school program that combines basic physics, aerodynamics, pre-engineering, 3D visualization, computer-assisted drafting, computer-assisted manufacturing, production, reengineering, and success in a 15-hour, 3-week classroom module. (JOW)

  5. Do focal colors look particularly "colorful"?

    Science.gov (United States)

    Witzel, Christoph; Franklin, Anna

    2014-04-01

    If the most typical red, yellow, green, and blue were particularly colorful (i.e., saturated), they would "jump out to the eye." This would explain why even fundamentally different languages have distinct color terms for these focal colors, and why unique hues play a prominent role in subjective color appearance. In this study, the subjective saturation of 10 colors around each of these focal colors was measured through a pairwise matching task. Results show that subjective saturation changes systematically across hues in a way that is strongly correlated to the visual gamut, and exponentially related to sensitivity but not to focal colors.

  6. Color doppler sonography in thickened gallbladder wall

    Energy Technology Data Exchange (ETDEWEB)

    Han, Sang Suk; Choi, Seok Jin; Seo, Chang Hae; Eun, Choong Ki [Inje Univ. College of Medicine, Kimhae (Korea, Republic of)

    1996-11-01

    The thickening of the gallbladder wall is a valuable finding for the diagnosis of cholecystitis, but may be seen in non-cholecystic disease as well as in acute or chronic cholecystitis. The purpose of this study is to determine the value of color Doppler sonography in differentiating the causes of thickened gallbladder wall. Ninety eight patients with thickened gallbladder wall(more than 3mm) which was not due to gallbladder cancer were prospectively evaluated with color Doppler sonography. Sixty-six cases, confirmed by pathologic reports and clinical records, were analyzed for correlation between thickened gallbladder wall and color flow signal according to the underlying causes. Of the 66 patients, 28 cases were cholecystitis and 38 cases had non-cholecystic causes such as liver cirrhosis, ascites, hepatitis, pancreatitis, renal failure, and hypoalbuminemia. Of the 28 patients with cholecystitis(12 acute, 16 chronic), 23(82%) had color Doppler flow signals in the thickened gallbladder wall. Of the 38 patients with non-cholecystic causes, eight(21%) had color Doppler flow signals. There was a statistically significant difference of color Doppler flow signals between the cholecystitis and non-cholecystic groups(p=0.0001). No significant difference of color Doppler flow signals was found between cases of acute and chronic cholecystitis. Of the 23 patients with color Doppler flow signals in 28 cases of cholecystitis, 18(78.3%) showed a linear pattern and five(21.7%) showed a spotty pattern. Of the eight patients with color Doppler flow signals in the 38 non-cholecystic cases, four(50%) showed a linear pattern and four(50%) showed a spotty pattern. In cholecystitis, a linear color Doppler flow signal pattern is a much more frequent finding than a spotty pattern. Color Doppler sonography is a useful and adequate method for determining whether a thickened gallbladder wall is the result of cholecystitis or has non-cholecystic causes.

  7. Qualitative skeletal correlates of wing shape in extant birds (Aves: Neoaves)

    OpenAIRE

    Hieronymus, Tobin L

    2015-01-01

    Background Among living fliers (birds, bats, and insects), birds display relatively high aspect ratios, a dimensionless shape variable that distinguishes long and narrow vs. short and broad wings. Increasing aspect ratio results in a functional tradeoff between low induced drag (efficient cruise) and increased wing inertia (difficult takeoff). Given the wide scope of its functional effects, the pattern of aspect ratio evolution is an important factor that contributes to the substantial ecolog...

  8. OBTENTION OF CARAMEL COLOR FOR CARBONATED BEVERAGES

    Directory of Open Access Journals (Sweden)

    Isnel Benítez Cortés

    2016-07-01

    Full Text Available This work is done in order to evaluate a process for the preparation of caramel color to produce carbonated soft drinks. The effect of the concentration of phosphoric acid and ammonium hydroxide in caramel color properties such as density, pH, color and Brix is evaluated and it is compared with a color pattern caramel color which was imported. The results indicate that the prepared sample with 3.6 mL of phosphoric acid and 46 mL of ammonium hydroxide has similar characteristics to the sample pattern. With this sample, iromber and cola syrup is prepared, showing very good results for the case of the cola, not so for iromber syrup. Durability studies are favorable, keeping the pH constant and color stability.

  9. Airplane wing deformation and flight flutter detection method by using three-dimensional speckle image correlation technology.

    Science.gov (United States)

    Wu, Jun; Yu, Zhijing; Wang, Tao; Zhuge, Jingchang; Ji, Yue; Xue, Bin

    2017-06-01

    Airplane wing deformation is an important element of aerodynamic characteristics, structure design, and fatigue analysis for aircraft manufacturing, as well as a main test content of certification regarding flutter for airplanes. This paper presents a novel real-time detection method for wing deformation and flight flutter detection by using three-dimensional speckle image correlation technology. Speckle patterns whose positions are determined through the vibration characteristic of the aircraft are coated on the wing; then the speckle patterns are imaged by CCD cameras which are mounted inside the aircraft cabin. In order to reduce the computation, a matching technique based on Geodetic Systems Incorporated coded points combined with the classical epipolar constraint is proposed, and a displacement vector map for the aircraft wing can be obtained through comparing the coordinates of speckle points before and after deformation. Finally, verification experiments containing static and dynamic tests by using an aircraft wing model demonstrate the accuracy and effectiveness of the proposed method.

  10. Review Results on Wing-Body Interference

    Directory of Open Access Journals (Sweden)

    Frolov Vladimir

    2016-01-01

    Full Text Available The paper presents an overview of results for wing-body interference, obtained by the author for varied wing-body combinations. The lift-curve slopes of the wing-body combinations are considered. In this paper a discrete vortices method (DVM and 2D potential model for cross-flow around fuselage are used. The circular and elliptical cross-sections of the fuselage and flat wings of various forms are considered. Calculations showed that the value of the lift-curve slopes of the wing-body combinations may exceed the same value for an isolated wing. This result confirms an experimental data obtained by other authors earlier. Within a framework of the used mathematical models the investigations to optimize the wing-body combination were carried. The present results of the optimization problem for the wing-body combination allowed to select the optimal geometric characteristics for configuration to maximize the values of the lift-curve slopes of the wing-body combination. It was revealed that maximums of the lift-curve slopes for the optimal mid-wing configuration with elliptical cross-section body had a sufficiently large relative width of the body (more than 30% of the span wing.

  11. Color preferences change after experience with liked/disliked colored objects.

    Science.gov (United States)

    Strauss, Eli D; Schloss, Karen B; Palmer, Stephen E

    2013-10-01

    How are color preferences formed, and can they be changed by affective experiences with correspondingly colored objects? We examined these questions by testing whether affectively polarized experiences with images of colored objects would cause changes in color preferences. Such changes are implied by the ecological valence theory (EVT), which posits that color preferences are determined by people's average affective responses to correspondingly colored objects (Palmer & Schloss, Proceedings of the National Academy of Sciences, 107, 8877-8882, 2010). Seeing images of strongly liked (and disliked) red and green objects, therefore, should lead to increased (and decreased) preferences for correspondingly colored red and green color patches. Experiment 1 showed that this crossover interaction did occur, but only if participants were required to evaluate their preferences for the colored objects when they saw them. Experiment 2 showed that these overall changes decreased substantially over a 24-h delay, but the degree to which the effect lasted for individuals covaried with the magnitude of the effects immediately after object exposure. Experiment 3 demonstrated a similar, but weaker, effect of affectively biased changes in color preferences when participants did not see, but only imagined, the colored objects. The overall pattern of results indicated that color preferences are not fixed, but rather are shaped by affective experiences with colored objects. Possible explanations for the observed changes in color preferences were considered in terms of associative learning through evaluative conditioning and/or priming of prior knowledge in memory.

  12. A single basis for developmental buffering of Drosophila wing shape.

    Directory of Open Access Journals (Sweden)

    Casper J Breuker

    2006-12-01

    Full Text Available The nature of developmental buffering processes has been debated extensively, based on both theoretical reasoning and empirical studies. In particular, controversy has focused on the question of whether distinct processes are responsible for canalization, the buffering against environmental or genetic variation, and for developmental stability, the buffering against random variation intrinsic in developmental processes. Here, we address this question for the size and shape of Drosophila melanogaster wings in an experimental design with extensively replicated and fully controlled genotypes. The amounts of variation among individuals and of fluctuating asymmetry differ markedly among genotypes, demonstrating a clear genetic basis for size and shape variability. For wing shape, there is a high correlation between the amounts of variation among individuals and fluctuating asymmetry, which indicates a correspondence between the two types of buffering. Likewise, the multivariate patterns of shape variation among individuals and of fluctuating asymmetry show a close association. For wing size, however, the amounts of individual variation and fluctuating asymmetry are not correlated. There was a significant link between the amounts of variation between wing size and shape, more so for fluctuating asymmetry than for variation among individuals. Overall, these experiments indicate a considerable degree of shared control of individual variation and fluctuating asymmetry, although it appears to differ between traits.

  13. Color preference in red–green dichromats

    Science.gov (United States)

    Álvaro, Leticia; Moreira, Humberto; Lillo, Julio; Franklin, Anna

    2015-01-01

    Around 2% of males have red–green dichromacy, which is a genetic disorder of color vision where one type of cone photoreceptor is missing. Here we investigate the color preferences of dichromats. We aim (i) to establish whether the systematic and reliable color preferences of normal trichromatic observers (e.g., preference maximum at blue, minimum at yellow-green) are affected by dichromacy and (ii) to test theories of color preference with a dichromatic sample. Dichromat and normal trichromat observers named and rated how much they liked saturated, light, dark, and focal colors twice. Trichromats had the expected pattern of preference. Dichromats had a reliable pattern of preference that was different to trichromats, with a preference maximum rather than minimum at yellow and a much weaker preference for blue than trichromats. Color preference was more affected in observers who lacked the cone type sensitive to long wavelengths (protanopes) than in those who lacked the cone type sensitive to medium wavelengths (deuteranopes). Trichromats’ preferences were summarized effectively in terms of cone-contrast between color and background, and yellow-blue cone-contrast could account for dichromats’ pattern of preference, with some evidence for residual red–green activity in deuteranopes’ preference. Dichromats’ color naming also could account for their color preferences, with colors named more accurately and quickly being more preferred. This relationship between color naming and preference also was present for trichromat males but not females. Overall, the findings provide novel evidence on how dichromats experience color, advance the understanding of why humans like some colors more than others, and have implications for general theories of aesthetics. PMID:26170287

  14. Winged messengers of disaster

    International Nuclear Information System (INIS)

    Medvedev, Z.

    1977-01-01

    The work of the Soviet ecologists, led by A.I. Il'enko, on birds in the southern Urals area, site of the nuclear disaster in 1958, is discussed. The distribution of 90 Sr and 137 Cs in birds, food chains in a large running-water lake, bird migration patterns, and nest conservatism of ducks have been studied. It is pointed out that the existence of migratory species among contaminated species of the southern Urals provides an opportunity for observers in the West to test the truth about the 1958 nuclear disaster in the southern Urals. It is felt that the reports discussed here corroborate the author's original statement that the Urals nuclear disaster involved nuclear waste rather than a major reactor accident. (U.K.)

  15. Cross-cultural color-odor associations.

    Directory of Open Access Journals (Sweden)

    Carmel A Levitan

    Full Text Available Colors and odors are associated; for instance, people typically match the smell of strawberries to the color pink or red. These associations are forms of crossmodal correspondences. Recently, there has been discussion about the extent to which these correspondences arise for structural reasons (i.e., an inherent mapping between color and odor, statistical reasons (i.e., covariance in experience, and/or semantically-mediated reasons (i.e., stemming from language. The present study probed this question by testing color-odor correspondences in 6 different cultural groups (Dutch, Netherlands-residing-Chinese, German, Malay, Malaysian-Chinese, and US residents, using the same set of 14 odors and asking participants to make congruent and incongruent color choices for each odor. We found consistent patterns in color choices for each odor within each culture, showing that participants were making non-random color-odor matches. We used representational dissimilarity analysis to probe for variations in the patterns of color-odor associations across cultures; we found that US and German participants had the most similar patterns of associations, followed by German and Malay participants. The largest group differences were between Malay and Netherlands-resident Chinese participants and between Dutch and Malaysian-Chinese participants. We conclude that culture plays a role in color-odor crossmodal associations, which likely arise, at least in part, through experience.

  16. Modeling human color categorization

    NARCIS (Netherlands)

    van den Broek, Egon; Schouten, Th.E.; Kisters, P.M.F.

    A unique color space segmentation method is introduced. It is founded on features of human cognition, where 11 color categories are used in processing color. In two experiments, human subjects were asked to categorize color stimuli into these 11 color categories, which resulted in markers for a

  17. A Drosophila wing spot test

    International Nuclear Information System (INIS)

    Ayaki, Toshikazu; Yoshikawa, Isao; Niikawa, Norio; Hoshi, Masaharu.

    1986-01-01

    A Drosophila wing spot test system was used to investigate the effects of low doses of X-rays, gamma rays, and both 2.3 and 14.1 MeV neutrons on somatic chromosome mutation (SCM) induction. The incidence of SCM was significantly increased with any type of radiation, with evident linear dose-response relationship within the range of 3 to 20 cGy. It was estimated that relative biological effectiveness value for SCM induction of 2.3 MeV neutrons to X-rays and gamma rays is much higher than that of 14.1 MeV neutrons to those photons (2.4 vs 8.0). The Drosophila wing spot test system seems to become a promising in vivo experimental method for higher animals in terms of the lack of necessity for a marvelously large number of materials required in conventional test system. (Namekawa, K.)

  18. Aerodynamic effects of flexibility in flapping wings

    Science.gov (United States)

    Zhao, Liang; Huang, Qingfeng; Deng, Xinyan; Sane, Sanjay P.

    2010-01-01

    Recent work on the aerodynamics of flapping flight reveals fundamental differences in the mechanisms of aerodynamic force generation between fixed and flapping wings. When fixed wings translate at high angles of attack, they periodically generate and shed leading and trailing edge vortices as reflected in their fluctuating aerodynamic force traces and associated flow visualization. In contrast, wings flapping at high angles of attack generate stable leading edge vorticity, which persists throughout the duration of the stroke and enhances mean aerodynamic forces. Here, we show that aerodynamic forces can be controlled by altering the trailing edge flexibility of a flapping wing. We used a dynamically scaled mechanical model of flapping flight (Re ≈ 2000) to measure the aerodynamic forces on flapping wings of variable flexural stiffness (EI). For low to medium angles of attack, as flexibility of the wing increases, its ability to generate aerodynamic forces decreases monotonically but its lift-to-drag ratios remain approximately constant. The instantaneous force traces reveal no major differences in the underlying modes of force generation for flexible and rigid wings, but the magnitude of force, the angle of net force vector and centre of pressure all vary systematically with wing flexibility. Even a rudimentary framework of wing veins is sufficient to restore the ability of flexible wings to generate forces at near-rigid values. Thus, the magnitude of force generation can be controlled by modulating the trailing edge flexibility and thereby controlling the magnitude of the leading edge vorticity. To characterize this, we have generated a detailed database of aerodynamic forces as a function of several variables including material properties, kinematics, aerodynamic forces and centre of pressure, which can also be used to help validate computational models of aeroelastic flapping wings. These experiments will also be useful for wing design for small robotic

  19. Aerodynamic effects of flexibility in flapping wings.

    Science.gov (United States)

    Zhao, Liang; Huang, Qingfeng; Deng, Xinyan; Sane, Sanjay P

    2010-03-06

    Recent work on the aerodynamics of flapping flight reveals fundamental differences in the mechanisms of aerodynamic force generation between fixed and flapping wings. When fixed wings translate at high angles of attack, they periodically generate and shed leading and trailing edge vortices as reflected in their fluctuating aerodynamic force traces and associated flow visualization. In contrast, wings flapping at high angles of attack generate stable leading edge vorticity, which persists throughout the duration of the stroke and enhances mean aerodynamic forces. Here, we show that aerodynamic forces can be controlled by altering the trailing edge flexibility of a flapping wing. We used a dynamically scaled mechanical model of flapping flight (Re approximately 2000) to measure the aerodynamic forces on flapping wings of variable flexural stiffness (EI). For low to medium angles of attack, as flexibility of the wing increases, its ability to generate aerodynamic forces decreases monotonically but its lift-to-drag ratios remain approximately constant. The instantaneous force traces reveal no major differences in the underlying modes of force generation for flexible and rigid wings, but the magnitude of force, the angle of net force vector and centre of pressure all vary systematically with wing flexibility. Even a rudimentary framework of wing veins is sufficient to restore the ability of flexible wings to generate forces at near-rigid values. Thus, the magnitude of force generation can be controlled by modulating the trailing edge flexibility and thereby controlling the magnitude of the leading edge vorticity. To characterize this, we have generated a detailed database of aerodynamic forces as a function of several variables including material properties, kinematics, aerodynamic forces and centre of pressure, which can also be used to help validate computational models of aeroelastic flapping wings. These experiments will also be useful for wing design for small

  20. Embedding Color Watermarks in Color Images

    Directory of Open Access Journals (Sweden)

    Wu Tung-Lin

    2003-01-01

    Full Text Available Robust watermarking with oblivious detection is essential to practical copyright protection of digital images. Effective exploitation of the characteristics of human visual perception to color stimuli helps to develop the watermarking scheme that fills the requirement. In this paper, an oblivious watermarking scheme that embeds color watermarks in color images is proposed. Through color gamut analysis and quantizer design, color watermarks are embedded by modifying quantization indices of color pixels without resulting in perceivable distortion. Only a small amount of information including the specification of color gamut, quantizer stepsize, and color tables is required to extract the watermark. Experimental results show that the proposed watermarking scheme is computationally simple and quite robust in face of various attacks such as cropping, low-pass filtering, white-noise addition, scaling, and JPEG compression with high compression ratios.

  1. Glass scales on the wing of the swordtail butterfly Graphium sarpedon act as thin film polarizing reflectors

    NARCIS (Netherlands)

    Stavenga, Doekele G.; Matsushita, Atsuko; Arikawa, Kentaro; Leertouwer, Hein L.; Wilts, Bodo D.

    The wings of the swordtail butterfly Graphium sarpedon (the Common Bluebottle) have blue/green-colored patches that are covered on the underside by two types of scales: white and glass scales. Transmission and scanning electron microscopy revealed that the white scales are classically structured:

  2. Colored Contact Lens Dangers

    Medline Plus

    Full Text Available ... One Use Facts About Colored Contacts and Halloween Safety Colored Contact Lens Facts Over-the-Counter Costume ... Costume Contact Lenses Can Ruin Vision Eye Makeup Safety In fact, it is illegal to sell colored ...

  3. Tooth - abnormal colors

    Science.gov (United States)

    ... medlineplus.gov/ency/article/003065.htm Tooth - abnormal colors To use the sharing features on this page, please enable JavaScript. Abnormal tooth color is any color other than white to yellowish- ...

  4. Urine - abnormal color

    Science.gov (United States)

    ... medlineplus.gov/ency/article/003139.htm Urine - abnormal color To use the sharing features on this page, please enable JavaScript. The usual color of urine is straw-yellow. Abnormally colored urine ...

  5. Skin color - patchy

    Science.gov (United States)

    ... page: //medlineplus.gov/ency/article/003224.htm Skin color - patchy To use the sharing features on this page, please enable JavaScript. Patchy skin color is areas where the skin color is irregular. ...

  6. Shape optimisation and performance analysis of flapping wings

    KAUST Repository

    Ghommem, Mehdi

    2012-09-04

    -averaged thrust, while the average aerodynamic power is increased. Furthermore, increasing the number of variables (i.e., providing the wing shape with greater degrees of spatial freedom) is observed to enable superior designs. To gain a better understanding of the reasons for which the obtained optimised shapes produce efficient flapping flights, the wake pattern and its vorticity strength are examined. This work described in this paper should facilitate better guidance for shape design of engineered flying systems.

  7. The costae presenting in high-temperature-induced vestigial wings ...

    Indian Academy of Sciences (India)

    Most of the wings have defects in the wing blade and partially formed wing margin, which are the result of autonomous cell death in the ... [Yang D. 2007 The costae presenting in high-temperature-induced vestigial wings of Drosophila: implications for anterior wing margin formation. J. Genet. .... The relevant gene(s) may be.

  8. Role of wing morphing in thrust generation

    Directory of Open Access Journals (Sweden)

    Mehdi Ghommem

    2014-01-01

    Full Text Available In this paper, we investigate the role of morphing on flight dynamics of two birds by simulating the flow over rigid and morphing wings that have the characteristics of two different birds, namely the Giant Petrel and Dove Prion. The simulation of a flapping rigid wing shows that the root of the wing should be placed at a specific angle of attack in order to generate enough lift to balance the weight of the bird. However, in this case the generated thrust is either very small, or even negative, depending on the wing shape. Further, results show that morphing of the wing enables a significant increase in the thrust and propulsive efficiency. This indicates that the birds actually utilize some sort of active wing twisting and bending to produce enough thrust. This study should facilitate better guidance for the design of flapping air vehicles.

  9. Winged scapula incidence and upper limb morbidity after surgery for breast cancer with axillary dissection.

    Science.gov (United States)

    Rizzi, Samantha Karlla Lopes de Almeida; Haddad, Cinira Assad Simão; Giron, Patricia Santolia; Pinheiro, Thaís Lúcia; Nazário, Afonso Celso Pinto; Facina, Gil

    2016-06-01

    The aim of this study was to determine the incidence of winged scapula after breast cancer surgery, its impact on shoulder morbidity and difference in incidence according to surgery type. Patients with breast cancer and surgical indication for axillary dissection were included. A total of 112 patients were surveyed with one physical evaluation before the surgery and others 15, 30, 90, and 180 days after. Winged scapula was assessed with test proposed by Hoppenfeld. Shoulder range of motion (ROM) was assessed with goniometer for flexion, extension, adduction, abduction, internal rotation, and external rotation. A verbal scale from 0 to 10 was used to assess pain. Winged scapula incidence was 8.0 % 15 days after surgery. Two patients recovered from winged scapula 90 days after surgery and four more 180 days after surgery, while three patients still had winged scapula at this time. The incidence after 15 days from surgery was 20.9 and 22.6 % among patients submitted to sentinel node biopsy or axillary lymphadenectomy (AL), respectively (p < 0.01). There was no statistical difference of incidence according to breast surgery type. Operated side shoulder flexion, adduction, and abduction ROM changes were statistically different in patients with or without winged scapula. The mean reduction was higher in patients with winged scapula. Both groups showed the same pattern over time in pain. Winged scapula incidence was 8.0 % and was higher in AL, and prevalence decreased during 6 months after surgery. Patients who developed winged scapula had more shoulder flexion, adduction, and abduction limitation.

  10. Differences in wing melanization and pigmentation pattern in Drosophila buzzatii (Diptera: Drosophilidae under chemical stress Diferencias en la melanización y el patrón de pigmentación alar en Drosophila buzzatii (Diptera: Drosophilidae bajo estrés químico

    Directory of Open Access Journals (Sweden)

    Nicolás Mongiardino Koch

    2012-06-01

    Full Text Available Recently, the genetic basis and developmental mechanisms underlying the process of melanization have become progressively elucidated, allowing us to study the evolutionary processes that govern the huge variability of pigmentation observed in nature. However, environmental factors contributing to such variability have received little attention, even though they might have profound ecological consequences. Here we describe a method for analyzing the wing melanization patterns of drosophilids in both qualitative and quantitative ways. We test this method on wings of Drosophila buzzatii Patterson & Wheeler individuals, reared in control and alkaloid-enriched mediums. The alkaloids were extracted from the secondary host of these flies, Echinopsis terscheckii (Parm. ex Pfeiff. Friedrich & Rowley, and their effect on wing pigmentation is analyzed, bearing in mind the adverse effects that these compounds have on the development of D. buzzatii. Alkaloid-reared flies were shown to attain a higher degree of wing melanization, accompanied with differences in the spatial distribution of the pigment. Modifications at both metabolic and gene regulatory levels are proposed to explain the changes that chemical stressful conditions are shown to induce in this character. We propose the utilization of this procedure in studies of environmental dependence of pigmentation.Recientemente, hemos avanzado en nuestra comprensión de las bases genéticas y los mecanismos subyacentes al proceso de melanización durante el desarrollo, lo que permite el estudio de los procesos evolutivos que gobiernan la variabilidad de pigmentación presente en la naturaleza. Sin embargo, los factores ambientales que contribuyen a dicha variabilidad han recibido poca atención, aún cuando pueden conllevar profundas consecuencias a nivel ecológico. En este trabajo, presentamos un método para analizar los patrones de melanización alar de drosofílidos, de forma cualitativa y cuantitativa

  11. Digital color imaging

    CERN Document Server

    Fernandez-Maloigne, Christine; Macaire, Ludovic

    2013-01-01

    This collective work identifies the latest developments in the field of the automatic processing and analysis of digital color images.For researchers and students, it represents a critical state of the art on the scientific issues raised by the various steps constituting the chain of color image processing.It covers a wide range of topics related to computational color imaging, including color filtering and segmentation, color texture characterization, color invariant for object recognition, color and motion analysis, as well as color image and video indexing and retrieval. <

  12. Notch inhibits Yorkie activity in Drosophila wing discs.

    Directory of Open Access Journals (Sweden)

    Alexandre Djiane

    Full Text Available During development, tissues and organs must coordinate growth and patterning so they reach the right size and shape. During larval stages, a dramatic increase in size and cell number of Drosophila wing imaginal discs is controlled by the action of several signaling pathways. Complex cross-talk between these pathways also pattern these discs to specify different regions with different fates and growth potentials. We show that the Notch signaling pathway is both required and sufficient to inhibit the activity of Yorkie (Yki, the Salvador/Warts/Hippo (SWH pathway terminal transcription activator, but only in the central regions of the wing disc, where the TEAD factor and Yki partner Scalloped (Sd is expressed. We show that this cross-talk between the Notch and SWH pathways is mediated, at least in part, by the Notch target and Sd partner Vestigial (Vg. We propose that, by altering the ratios between Yki, Sd and Vg, Notch pathway activation restricts the effects of Yki mediated transcription, therefore contributing to define a zone of low proliferation in the central wing discs.

  13. Qualitative skeletal correlates of wing shape in extant birds (Aves: Neoaves).

    Science.gov (United States)

    Hieronymus, Tobin L

    2015-02-27

    Among living fliers (birds, bats, and insects), birds display relatively high aspect ratios, a dimensionless shape variable that distinguishes long and narrow vs. short and broad wings. Increasing aspect ratio results in a functional tradeoff between low induced drag (efficient cruise) and increased wing inertia (difficult takeoff). Given the wide scope of its functional effects, the pattern of aspect ratio evolution is an important factor that contributes to the substantial ecological and phylogenetic diversity of living birds. However, because the feathers that define the wingtip (and hence wingspan and aspect ratio) often do not fossilize, resolution in the pattern of avian wing shape evolution is obscured by missing information. Here I use a comparative approach to investigate the relationship between skeletal proxies of flight feather attachment and wing shape. An accessory lobe of the internal index process of digit II-1, a bony correlate of distal primary attachment, shows weak but statistically significant relationships to aspect ratio and mass independent of other skeletal morphology. The dorsal phalangeal fossae of digit II-1, which house distal primaries VIII and IX, also show a trend of increased prominence with higher aspect ratio. Quill knobs on the ulna are examined concurrently, but do not show consistent signal with respect to wing shape. Although quill knobs are cited as skeletal correlates of flight performance in birds, their relationship to wing shape is inconsistent among extant taxa, and may reflect diverging selection pressures acting on a conserved architecture. In contrast, correlates of distal primary feather attachment on the major digit show convergent responses to increasing aspect ratio. In light of the diversity of musculoskeletal and integumentary mophology that underlies wing shape in different avian clades, it is unlikely that a single skeletal feature will show consistent predictive power across Neoaves. Confident inference of

  14. Analysis of bat wings for morphing

    Science.gov (United States)

    Leylek, Emily A.; Manzo, Justin E.; Garcia, Ephrahim

    2008-03-01

    The morphing of wings from three different bat species is studied using an extension of the Weissinger method. To understand how camber affects performance factors such as lift and lift to drag ratio, XFOIL is used to study thin (3% thickness to chord ratio) airfoils at a low Reynolds number of 100,000. The maximum camber of 9% yielded the largest lift coefficient, and a mid-range camber of 7% yielded the largest lift to drag ratio. Correlations between bat wing morphology and flight characteristics are covered, and the three bat wing planforms chosen represent various combinations of morphological components and different flight modes. The wings are studied using the extended Weissinger method in an "unmorphed" configuration using a thin, symmetric airfoil across the span of the wing through angles of attack of 0°-15°. The wings are then run in the Weissinger method at angles of attack of -2° to 12° in a "morphed" configuration modeled after bat wings seen in flight, where the camber of the airfoils comprising the wings is varied along the span and a twist distribution along the span is introduced. The morphed wing configurations increase the lift coefficient over 1000% from the unmorphed configuration and increase the lift to drag ratio over 175%. The results of the three different species correlate well with their flight in nature.

  15. Harmonious colors: from alchemy to science

    Science.gov (United States)

    Beretta, Giordano B.; Moroney, Nathan M.

    2012-01-01

    There is a very long tradition in designing color palettes for various applications, going back to at least the Upanishad. Although color palettes have been influenced by the available colorants, starting with the advent of aniline dyes in the late 1850s there have been few physical limits on the choice of individual colors. This abundance of choices exacerbates the problem of limiting the number of colors in a palette, i.e., in keeping them into a manageable quantity. For example, it is not practical for a car company to offer each model in hundreds of colors. Instead, for each model year a small number of color palettes is offered, each containing the colors for the body, trim, interior, etc. Another example is the fashion industry, where in addition to solid colors there are also patterns, leading to a huge variety of combinations that would be impossible to stock. The traditional solution is that of "color forecasting." Color consultants assess the sentiment or affective state of a target customer class and compare it with new colorants offered by the industry. They assemble a limited color palette, name the colors according to the sentiment, and publish their result. Textile manufacturers will produce fabrics in these colors and fashion designers will design clothes, accessories, and furniture based on these fabrics. Eventually, the media will communicate these forecasts to the consumers, who will be admired by their cohorts when they choose colors from the forecast palette, which by then is widely diffused. The color forecasting business is very labor intensive and difficult, thus for years computer engineers have tried to come up with algorithms to design harmonious color palettes, alas with little commercial success. For example, Johannes Itten's color theory has been implemented many times, but despite Itten's success in the Bauhaus artifacts, the computer tools have been of little utility. Indeed, contrary to the auditory sense, there is no known

  16. Color relations increase the capacity of visual short-term memory.

    Science.gov (United States)

    Sanocki, Thomas; Sulman, Noah

    2011-01-01

    Do color relations such as similarity or harmony influence the ease with which colored patterns can be perceived and held in mind? We tested the influence of a relation supported in research on color harmony--similarity of hue--on the capacity of visual short-term memory (VSTM) for colors in patterns. Palettes of 4 similar-hue colors were rated as more pleasant (harmonious) than dissimilar-color palettes. The palettes were used in a VSTM color task. Patterns of 9 to 15 colored squares were presented, and accuracy of color change detection was measured. Memory performance was higher overall for similar-color palettes than for dissimilar-color palettes (experiments 1 and 3). Is this due to color similarity per se, or due to the harmony between colors in similar palettes? A final experiment provided strong support for the importance of color similarity as opposed to harmony. Overall, the advantages for color similarity, in terms of number of color squares held in memory (memory capacity) were 26% to 45% over dissimilar colors. The results indicate that color relations can have a strong impact on the capacity for perceiving and retaining color patterns.

  17. Quad-thopter: Tailless Flapping Wing Robot with 4 Pairs of Wings

    NARCIS (Netherlands)

    de Wagter, C.; Karasek, M.; de Croon, G.C.H.E.; J.-M. Moschetta G. Hattenberger, H. de Plinval

    2017-01-01

    We present a novel design of a tailless flapping wing Micro Air Vehicle (MAV), which uses four independently driven pairs of flapping wings in order to fly and perform agile maneuvers. The wing pairs are arranged such that differential thrust generates the desired roll and pitch moments, similar to

  18. Memory for color reactivates color processing region.

    Science.gov (United States)

    Slotnick, Scott D

    2009-11-25

    Memory is thought to be constructive in nature, where features processed in different cortical regions are synthesized during retrieval. In an effort to support this constructive memory framework, the present functional magnetic resonance imaging study assessed whether memory for color reactivated color processing regions. During encoding, participants were presented with colored and gray abstract shapes. During retrieval, old and new shapes were presented in gray and participants responded 'old-colored', 'old-gray', or 'new'. Within color perception regions, color memory related activity was observed in the left fusiform gyrus, adjacent to the collateral sulcus. A retinotopic mapping analysis indicated this activity occurred within color processing region V8. The present feature specific evidence provides compelling support for a constructive view of memory.

  19. Natural Colorants: Food Colorants from Natural Sources.

    Science.gov (United States)

    Sigurdson, Gregory T; Tang, Peipei; Giusti, M Mónica

    2017-02-28

    The color of food is often associated with the flavor, safety, and nutritional value of the product. Synthetic food colorants have been used because of their high stability and low cost. However, consumer perception and demand have driven the replacement of synthetic colorants with naturally derived alternatives. Natural pigment applications can be limited by lower stability, weaker tinctorial strength, interactions with food ingredients, and inability to match desired hues. Therefore, no single naturally derived colorant can serve as a universal alternative for a specified synthetic colorant in all applications. This review summarizes major environmental and biological sources for natural colorants as well as nature-identical counterparts. Chemical characteristics of prevalent pigments, including anthocyanins, carotenoids, betalains, and chlorophylls, are described. The possible applications and hues (warm, cool, and achromatic) of currently used natural pigments, such as anthocyanins as red and blue colorants, and possible future alternatives, such as purple violacein and red pyranoanthocyanins, are also discussed.

  20. Modular color evolution facilitated by a complex nanostructure in birds.

    Science.gov (United States)

    Eliason, Chad M; Maia, Rafael; Shawkey, Matthew D

    2015-02-01

    The way in which a complex trait varies, and thus evolves, is critically affected by the independence, or modularity, of its subunits. How modular designs facilitate phenotypic diversification is well studied in nonornamental (e.g., cichlid jaws), but not ornamental traits. Diverse feather colors in birds are produced by light absorption by pigments and/or light scattering by nanostructures. Such structural colors are deterministically related to the nanostructures that produce them and are therefore excellent systems to study modularity and diversity of ornamental traits. Elucidating if and how these nanostructures facilitate color diversity relies on understanding how nanostructural traits covary, and how these traits map to color. Both of these remain unknown in an evolutionary context. Most dabbling ducks (Anatidae) have a conspicuous wing patch with iridescent color caused by a two-dimensional photonic crystal of small (100-200 nm) melanosomes. Here, we ask how this complex nanostructure affects modularity of color attributes. Using a combination of electron microscopy, spectrophotometry, and comparative methods, we show that nanostructural complexity causes functional decoupling and enables independent evolution of different color traits. These results demonstrate that color diversity is facilitated by how nanostructures function and may explain why some birds are more color-diverse than others. © 2014 The Author(s). Evolution © 2014 The Society for the Study of Evolution.

  1. Adaptive wing : Investigations of passive wing technologies for loads reduction in the cleansky smart fixed wing aircraft (SFWA) project

    NARCIS (Netherlands)

    Kruger, W.R.; Dillinger, J; De Breuker, R.; Reyes, M.; Haydn, K.

    2016-01-01

    In the work package “Adaptive Wing” in the Clean-Sky “Smart Fixed Wing Aircraft” (SFWA) project, design processes and solutions for aircraft wings have been created, giving optimal response with respect to loads, comfort and performance by the introduction of passive and active concepts. Central

  2. Bold colors in a cryptic lineage: do Eastern Indigo Snakes exhibit color dimorphism?

    Science.gov (United States)

    Deitloff, Jennifer; Johnson, Valerie M; Guyer, Craig

    2013-01-01

    Many species exhibit variation in the color of their scales, feathers, or fur. Various forms of natural selection, such as mimicry, crypsis, and species recognition, as well as sexual selection, can influence the evolution of color. Eastern Indigo Snakes (Drymarchon couperi), a federally threatened species, have coloration on the sides of the head and the chin that can vary from black to red or cream. Despite significant conservations efforts for this species, little is known about its biology in the field. Past researchers have proposed that the color variation on the head and chin is associated with the sex of the individual. Alternatively, color might vary among individuals because it is controlled by genes that are under natural selection or neutral evolution. We tested these alternative hypotheses by examining whether coloration of the sublabial, submaxillary, and ventral scales of this species differed by sex or among clutches. We used color spectrometry to characterize important aspects of color in two ways: by examining overall color differences across the entire color spectrum and by comparing differences within the ultraviolet, yellow, and red colorbands. We found that Eastern Indigo Snakes do not exhibit sexual dichromatism, but their coloration does vary among clutches; therefore, the pattern of sexual selection leading to sexual dichromatism observed in many squamates does not appear to play a role in the evolution and maintenance of color variation in Eastern Indigo Snakes. We suggest that future studies should focus on determining whether color variation in these snakes is determined by maternal effects or genetic components and if color is influenced by natural selection or neutral evolutionary processes. Studying species that exhibit bright colors within lineages that are not known for such coloration will contribute greatly to our understanding of the evolutionary and ecological factors that drive these differences.

  3. Impact of low-dose chronic exposure to Bisphenol A (BPA) on adult male zebrafish adaption to the environmental complexity: Disturbing the color preference patterns and reliving the anxiety behavior.

    Science.gov (United States)

    Li, Xiang; Sun, Ming-Zhu; Li, Xu; Zhang, Shu-Hui; Dai, Liang-Ti; Liu, Xing-Yu; Zhao, Xin; Chen, Dong-Yan; Feng, Xi-Zeng

    2017-11-01

    The extensive usage of xenobiotic endocrine disrupting chemicals (XEDCs), such as Bisphenol A (BPA), has created obvious threat to aquatic ecosystems worldwide. Although a comprehensive understanding of the adverse effect of BPA on behaviors and physiology have been proven, the potential impact of low-dose BPA on altering the basic ability of aquatic organism in adapting to the surrounded complex environment still remains elusive. In this research, we report that treatment of adult male zebrafish with chronic (7 weeks) low-dose (0.22 nM-2.2 nM) BPA, altered the ability in adapting the complex environment by disturbing the natural color preference patterns. In addition, chronic 50 ng/L (0.22 nM) BPA exposure alleviated the anxiety behavior of male zebrafish confronted with the novel environment by enhancing the preference towards light in the light/dark preference test. This phenotype was associated with less expression of serotonin (5-TH) in the hypothalamus and the down-regulation of tyrosine hydroxylase (TH) in brain tissues. As such, our results show that low-dose BPA remnant in surface waters altered zebrafish behavior that are known to have ecological and evolutionary consequences. Here we reported that the impact of chronic low-dose BPA exposure on the basic capability of zebrafish to adapt to the environmental complexity. Specifically, BPA at low concentration, under the environmental safety level and 3000-fold lower than the accepted human daily exposure, interfered with the ability to discriminate color and alleviate anxiety induced by the novel environment, which finally altered the capability of male zebrafish to adapt to the environmental complexity. These findings revealed the ecological effect of low-dose BPA and regular BPA concentration standard are not necessarily safe. The result also provided the consideration of retuning the hazard concentration level of BPA. Copyright © 2017 Elsevier Ltd. All rights reserved.

  4. Texture affects color emotion

    NARCIS (Netherlands)

    Lucassen, M.P.; Gevers, T.; Gijsenij, A.

    2011-01-01

    Several studies have recorded color emotions in subjects viewing uniform color (UC) samples. We conduct an experiment to measure and model how these color emotions change when texture is added to the color samples. Using a computer monitor, our subjects arrange samples along four scales: warm-cool,

  5. What is Color Blindness?

    Science.gov (United States)

    ... Stories Español Eye Health / Eye Health A-Z Color Blindness Sections What Is Color Blindness? What Are ... Treatment How Color Blindness Is Tested What Is Color Blindness? Leer en Español: ¿Qué es el daltonismo? ...

  6. Sensory Drive, Color, and Color Vision.

    Science.gov (United States)

    Price, Trevor D

    2017-08-01

    Colors often appear to differ in arbitrary ways among related species. However, a fraction of color diversity may be explained because some signals are more easily perceived in one environment rather than another. Models show that not only signals but also the perception of signals should regularly evolve in response to different environments, whether these primarily involve detection of conspecifics or detection of predators and prey. Thus, a deeper understanding of how perception of color correlates with environmental attributes should help generate more predictive models of color divergence. Here, I briefly review our understanding of color vision in vertebrates. Then I focus on opsin spectral tuning and opsin expression, two traits involved in color perception that have become amenable to study. I ask how opsin tuning is correlated with ecological differences, notably the light environment, and how this potentially affects perception of conspecific colors. Although opsin tuning appears to evolve slowly, opsin expression levels are more evolutionarily labile but have been difficult to connect to color perception. The challenge going forward will be to identify how physiological differences involved in color vision, such as opsin expression levels, translate into perceptual differences, the selection pressures that have driven those differences, and ultimately how this may drive evolution of conspecific colors.

  7. Color constancy in a scene with bright colors that do not have a fully natural surface appearance.

    Science.gov (United States)

    Fukuda, Kazuho; Uchikawa, Keiji

    2014-04-01

    Theoretical and experimental approaches have proposed that color constancy involves a correction related to some average of stimulation over the scene, and some of the studies showed that the average gives greater weight to surrounding bright colors. However, in a natural scene, high-luminance elements do not necessarily carry information about the scene illuminant when the luminance is too high for it to appear as a natural object color. The question is how a surrounding color's appearance mode influences its contribution to the degree of color constancy. Here the stimuli were simple geometric patterns, and the luminance of surrounding colors was tested over the range beyond the luminosity threshold. Observers performed perceptual achromatic setting on the test patch in order to measure the degree of color constancy and evaluated the surrounding bright colors' appearance mode. Broadly, our results support the assumption that the visual system counts only the colors in the object-color appearance for color constancy. However, detailed analysis indicated that surrounding colors without a fully natural object-color appearance had some sort of influence on color constancy. Consideration of this contribution of unnatural object color might be important for precise modeling of human color constancy.

  8. Color: Physics and Perception

    Science.gov (United States)

    Gilbert, Pupa

    Unless we are colorblind, as soon as we look at something, we know what color it is. Simple, isn't it? No, not really. The color we see is rarely just determined by the physical color, that is, the wavelength of visible light associated with that color. Other factors, such as the illuminating light, or the brightness surrounding a certain color, affect our perception of that color. Most striking, and useful, is understanding how the retina and the brain work together to interpret the color we see, and how they can be fooled by additive color mixing, which makes it possible to have color screens and displays. I will show the physical origin of all these phenomena and give live demos as I explain how they work. Bring your own eyes! For more information: (1) watch TED talk: ``Color: Physics and Perception'' and (2) read book: PUPA Gilbert and W Haeberli ``Physics in the Arts'', ISBN 9780123918789.

  9. Industrial Color Physics

    CERN Document Server

    Klein, Georg A

    2010-01-01

    This unique book starts with a short historical overview of the development of the theories of color vision and applications of industrial color physics. The three dominant factors producing color - light source, color sample, and observer - are described in detail. The standardized color spaces are shown and related color values are applied to characteristic color qualities of absorption as well as of effect colorants. The fundamentals of spectrometric and colorimetric measuring techniques together with specific applications are described. Theoretical models for radiative transfer in transparent, translucent, and opaque layers are detailed; the two, three, and multi-flux approximations are presented for the first time in a coherent formalism. These methods constitute the fundamentals not only for the important classical methods, but also modern methods of recipe prediction applicable to all known colorants. The text is supplied with 52 tables, more than 200 partially colored illustrations, an appendix, and a...

  10. Coloring local feature extraction

    OpenAIRE

    Van De Weijer, Joost; Schmid, Cordelia

    2006-01-01

    International audience; Although color is commonly experienced as an indispensable quality in describing the world around us, state-of-the art local feature-based representations are mostly based on shape description, and ignore color information. The description of color is hampered by the large amount of variations which causes the measured color values to vary significantly. In this paper we aim to extend the description of local features with color information. To accomplish a wide applic...

  11. Color models of hadrons

    International Nuclear Information System (INIS)

    Greenberg, O.W.; Nelson, C.A.

    1977-01-01

    The evidence for a three-valued 'color' degree of freedom in hadron physics is reviewed. The structure of color models is discussed. Consequences of color models for elementary particle physics are discussed, including saturation properties of hadronic states, π 0 →2γ and related decays, leptoproduction, and lepton pair annihilation. Signatures are given which distinguish theories with isolated colored particles from those in which color is permanently bound. (Auth.)

  12. The Realization and Study of Optical Wings

    Science.gov (United States)

    Artusio-Glimpse, Alexandra Brae

    Consider the airfoil: a carefully designed structure capable of stable lift in a uniform air flow. It so happens that air pressure and radiation (light) pressure are similar phenomena because each transfer momentum to flow-disturbing objects. This, then, begs the question: does an optical analogue to the airfoil exist? Though an exceedingly small effect, scientists harness radiation pressure in a wide gamut of applications from micromanipulation of single biological particles to the propulsion of large spacecrafts called solar sails. We introduce a cambered, refractive rod that is subjected to optical forces analogous to those seen in aerodynamics, and I call this analogue the optical wing. Flight characteristics of optical wings are determined by wing shape and material in a uniform radiation field. Theory predicts the lift force and axial torque are functions of the wing's angle of attack with stable and unstable orientations. These structures can operate as intensity-dependent, parametrically driven oscillators. In two-dimensions, the wings exhibit bistability when analyzed in an accelerating frame. In three-dimensions, the motion of axially symmetric spinning hemispherical wings is analogous to a spinning top. Experiments on semi-buoyant wings in water found semicylindrically shaped, refractive microparticles traversed a laser beam and rotated to an illumination-dependent stable orientation. Preliminary tests aid in the development of a calibrated force measurement experiment to directly evaluate the optical forces and torque on these samples. A foundational study of the optical wing, this work contributes to future advancements of flight-by-light.

  13. The Crest Wing Wave Energy Device

    DEFF Research Database (Denmark)

    Kofoed, Jens Peter; Antonishen, Michael Patrick

    This report presents the results of a continuation of an experimental study of the wave energy converting abilities of the Crest Wing wave energy converter (WEC), in the following referred to as ‘Phase 2'. The Crest Wing is a WEC that uses its movement in matching the shape of an oncoming wave...

  14. Effect of leading edge roundness on a delta wing in wing-rock motion

    Science.gov (United States)

    Ng, T. Terry; Malcolm, Gerald N.

    1990-01-01

    The effect of wing leading-edge roundness on wing rock was investigated using flow visualization in a water tunnel. Eighty degree delta wing models were tested on free-to-roll and forced oscillation rigs. The onset of wing rock was delayed by increasing the roundness of the leading edges. The wing rock amplitude and frequency results suggested that damping was increased at lower angles of attack but reduced at higher angles of attack. Vortex lift-off and vortex breakdown, especially during dynamic situations, were strongly affected by the leading edge roundness. Different forms of wing rock motion could be sustained by combinations of vortex breakdown and vortex lift-off. Behaviors of the wing and vortex motions were explained by the influence of leading edge roundness on the separation location, vortex trajectory, and vortex breakdown.

  15. Latitudinal gradient effect on the wing geometry of Auca coctei (Guérin(Lepidoptera, Nymphalidae

    Directory of Open Access Journals (Sweden)

    María-José Sanzana

    2013-12-01

    Full Text Available Latitudinal gradient effect on the wing geometry of Auca coctei (Guérin (Lepidoptera, Nymphalidae. When the environmental conditions change locally, the organisms and populations may also change in response to the selection pressure, so that the development of individuals may become affected in different degrees. There have been only a few studies in which the patterns of wing morphology variation have been looked into along a latitudinal gradient by means of geometric morphometrics. The aim of this work was to assess the morphologic differentiation of wing among butterfly populations of the species Auca coctei. For this purpose, 9 sampling locations were used which are representative of the distribution range of the butterfly and cover a wide latitudinal range in Chile. The wing morphology was studied in a total of 202 specimens of A. coctei (150 males and 52 females, based on digitization of 17 morphologic landmarks. The results show variation of wing shape in both sexes; however, for the centroid size there was significant variation only in females. Females show smaller centroid size at higher latitudes, therefore in this study the Bergmann reverse rule is confirmed for females of A. coctei. Our study extends morphologic projections with latitude, suggesting that wing variation is an environmental response from diverse origins and may influence different characteristics of the life history of a butterfly.

  16. Development of Bird-like Micro Aerial Vehicle with Flapping and Feathering Wing Motions

    Science.gov (United States)

    Maglasang, Jonathan; Goto, Norihiro; Isogai, Koji

    To investigate the feasibility of a highly efficient flapping system capable of avian maneuvers, such as rapid takeoff, hover and gliding, a full scale bird-like (ornithopter) flapping-wing micro aerial vehicle (MAV) shaped and patterned after a typical pigeon (Columba livia) has been designed and constructed. Both numerical and experimental methods have been used in the development of this vehicle. This flapping-wing micro aerial vehicle utilizes both the flapping and feathering motions of an avian wing by employing a novel flapping-feathering mechanism, which has been synthesized and constructed so as to best describe the properly coordinated flapping and feathering wing motions at phase angle difference of 90° in a horizontal steady level flight condition. This design allows high flapping and feathering amplitudes and is configurable for asymmetric wing motions which are desirable in high-speed flapping flight and maneuvering. The preliminary results indicate its viability as a practical and an efficient flapping-wing micro aerial vehicle.

  17. Novel method for measuring a dense 3D strain map of robotic flapping wings

    Science.gov (United States)

    Li, Beiwen; Zhang, Song

    2018-04-01

    Measuring dense 3D strain maps of the inextensible membranous flapping wings of robots is of vital importance to the field of bio-inspired engineering. Conventional high-speed 3D videography methods typically reconstruct the wing geometries through measuring sparse points with fiducial markers, and thus cannot obtain the full-field mechanics of the wings in detail. In this research, we propose a novel system to measure a dense strain map of inextensible membranous flapping wings by developing a superfast 3D imaging system and a computational framework for strain analysis. Specifically, first we developed a 5000 Hz 3D imaging system based on the digital fringe projection technique using the defocused binary patterns to precisely measure the dynamic 3D geometries of rapidly flapping wings. Then, we developed a geometry-based algorithm to perform point tracking on the precisely measured 3D surface data. Finally, we developed a dense strain computational method using the Kirchhoff-Love shell theory. Experiments demonstrate that our method can effectively perform point tracking and measure a highly dense strain map of the wings without many fiducial markers.

  18. Wing geometry of Culex coronator (Diptera: Culicidae) from South and Southeast Brazil.

    Science.gov (United States)

    Demari-Silva, Bruna; Suesdek, Lincoln; Sallum, Maria Anice Mureb; Marrelli, Mauro Toledo

    2014-04-09

    The Coronator Group encompasses Culex coronator Dyar & Knab, Culex camposi Dyar, Culex covagarciai Forattini, Culex ousqua Dyar, Culex usquatissimus Dyar, Culex usquatus Dyar and Culex yojoae Strickman. Culex coronator has the largest geographic distribution, occurring in North, Central and South America. Moreover, it is a potential vector-borne mosquito species because females have been found naturally infected with several arboviruses, i.e., Saint Louis Encephalitis Virus, Venezuelan Equine Encephalitis Virus and West Nile Virus. Considering the epidemiological importance of Cx. coronator, we investigated the wing shape diversity of Cx. coronator from South and Southeast Brazil, a method to preliminarily estimate population diversity. Field-collected immature stages of seven populations from a large geographical area in Brazil were maintained in the laboratory to obtain both females and males linked with pupal and/or larval exuviae. For each individual female, 18 landmarks of left wings were marked and digitalized. After Procrustes superimposition, discriminant analysis of shape was employed to quantify wing shape variation among populations. The isometric estimator centroid size was calculated to assess the overall wing size and allometry. Wing shape was polymorphic among populations of Cx. coronator. However, dissimilarities among populations were higher than those observed within each population, suggesting populational differentiation in Cx. coronator. Morphological distances between populations were not correlated to geographical distances, indicating that other factors may act on wing shape and thus, determining microevolutionary patterns in Cx. coronator. Despite the population differentiation, intrapopulational wing shape variability was equivalent among all seven populations. The wing variability found in Cx. coronator populations brings to light a new biological problem to be investigated: the population genetics of Cx. coronator. Because of differences

  19. Perception of color emotions for single colors in red-green defective observers.

    Science.gov (United States)

    Sato, Keiko; Inoue, Takaaki

    2016-01-01

    It is estimated that inherited red-green color deficiency, which involves both the protan and deutan deficiency types, is common in men. For red-green defective observers, some reddish colors appear desaturated and brownish, unlike those seen by normal observers. Despite its prevalence, few studies have investigated the effects that red-green color deficiency has on the psychological properties of colors (color emotions). The current study investigated the influence of red-green color deficiency on the following six color emotions: cleanliness, freshness, hardness, preference, warmth, and weight. Specifically, this study aimed to: (1) reveal differences between normal and red-green defective observers in rating patterns of six color emotions; (2) examine differences in color emotions related to the three cardinal channels in human color vision; and (3) explore relationships between color emotions and color naming behavior. Thirteen men and 10 women with normal vision and 13 men who were red-green defective performed both a color naming task and an emotion rating task with 32 colors from the Berkeley Color Project (BCP). Results revealed noticeable differences in the cleanliness and hardness ratings between the normal vision observers, particularly in women, and red-green defective observers, which appeared mainly for colors in the orange to cyan range, and in the preference and warmth ratings for colors with cyan and purple hues. Similarly, naming errors also mainly occurred in the cyan colors. A regression analysis that included the three cone-contrasts (i.e., red-green, blue-yellow, and luminance) as predictors significantly accounted for variability in color emotion ratings for the red-green defective observers as much as the normal individuals. Expressly, for warmth ratings, the weight of the red-green opponent channel was significantly lower in color defective observers than in normal participants. In addition, the analyses for individual warmth ratings in

  20. Perception of color emotions for single colors in red-green defective observers

    Directory of Open Access Journals (Sweden)

    Keiko Sato

    2016-12-01

    Full Text Available It is estimated that inherited red-green color deficiency, which involves both the protan and deutan deficiency types, is common in men. For red-green defective observers, some reddish colors appear desaturated and brownish, unlike those seen by normal observers. Despite its prevalence, few studies have investigated the effects that red-green color deficiency has on the psychological properties of colors (color emotions. The current study investigated the influence of red-green color deficiency on the following six color emotions: cleanliness, freshness, hardness, preference, warmth, and weight. Specifically, this study aimed to: (1 reveal differences between normal and red-green defective observers in rating patterns of six color emotions; (2 examine differences in color emotions related to the three cardinal channels in human color vision; and (3 explore relationships between color emotions and color naming behavior. Thirteen men and 10 women with normal vision and 13 men who were red-green defective performed both a color naming task and an emotion rating task with 32 colors from the Berkeley Color Project (BCP. Results revealed noticeable differences in the cleanliness and hardness ratings between the normal vision observers, particularly in women, and red-green defective observers, which appeared mainly for colors in the orange to cyan range, and in the preference and warmth ratings for colors with cyan and purple hues. Similarly, naming errors also mainly occurred in the cyan colors. A regression analysis that included the three cone-contrasts (i.e., red-green, blue-yellow, and luminance as predictors significantly accounted for variability in color emotion ratings for the red-green defective observers as much as the normal individuals. Expressly, for warmth ratings, the weight of the red-green opponent channel was significantly lower in color defective observers than in normal participants. In addition, the analyses for individual warmth

  1. Color-avoiding percolation

    Science.gov (United States)

    Krause, Sebastian M.; Danziger, Michael M.; Zlatić, Vinko

    2017-08-01

    Many real world networks have groups of similar nodes which are vulnerable to the same failure or adversary. Nodes can be colored in such a way that colors encode the shared vulnerabilities. Using multiple paths to avoid these vulnerabilities can greatly improve network robustness, if such paths exist. Color-avoiding percolation provides a theoretical framework for analyzing this scenario, focusing on the maximal set of nodes which can be connected via multiple color-avoiding paths. In this paper we extend the basic theory of color-avoiding percolation that was published in S. M. Krause et al. [Phys. Rev. X 6, 041022 (2016)], 10.1103/PhysRevX.6.041022. We explicitly account for the fact that the same particular link can be part of different paths avoiding different colors. This fact was previously accounted for with a heuristic approximation. Here we propose a better method for solving this problem which is substantially more accurate for many avoided colors. Further, we formulate our method with differentiated node functions, either as senders and receivers, or as transmitters. In both functions, nodes can be explicitly trusted or avoided. With only one avoided color we obtain standard percolation. Avoiding additional colors one by one, we can understand the critical behavior of color-avoiding percolation. For unequal color frequencies, we find that the colors with the largest frequencies control the critical threshold and exponent. Colors of small frequencies have only a minor influence on color-avoiding connectivity, thus allowing for approximations.

  2. Hovering hummingbird wing aerodynamics during the annual cycle. II. Implications of wing feather moult

    Science.gov (United States)

    Sapir, Nir; Elimelech, Yossef

    2018-01-01

    Birds usually moult their feathers in a particular sequence which may incur aerodynamic, physiological and behavioural implications. Among birds, hummingbirds are unique species in their sustained hovering flight. Because hummingbirds frequently hover-feed, they must maintain sufficiently high flight capacities even when moulting their flight feathers. A hummingbird wing consists of 10 primary flight feathers whose absence during moult may strongly affect wing performance. Using dynamic similarity rules, we compared time-accurate aerodynamic loads and flow field measurements over several wing geometries that follow the natural feather moult sequence of Calypte anna, a common hummingbird species in western North America. Our results suggest a drop of more than 20% in lift production during the early stages of the moult sequence in which mid-wing flight feathers are moulted. We also found that the wing's ability to generate lift strongly depended on the morphological integrity of the outer primaries and leading-edge. These findings may explain the evolution of wing morphology and moult attributes. Specifically, the high overlap between adjacent wing feathers, especially at the wing tip, and the slow sequential replacement of the wing feathers result in a relatively small reduction in wing surface area during moult with limited aerodynamic implications. We present power and efficiency analyses for hover flight during moult under several plausible scenarios, suggesting that body mass reduction could be a compensatory mechanism that preserves the energetic costs of hover flight. PMID:29515884

  3. Resilin-based rubber-like elements in the insect wing: an overview

    Energy Technology Data Exchange (ETDEWEB)

    Gorb, S.N. [Max-Planck-Institut fuer Entwicklungsbiologie, Tuebingen (Germany). Abt. Biochemie

    2001-06-01

    Wings of insects are complex structures which are designed to enable controlled torsion essential to flapping flight. Although wing morphology and flight types diversified enormously among a huge number of insect species, the general principle of insect flight remained the same. All muscles are located in the thorax proper, the wing itself is complete without any muscles. Data on the nature and distribution of materials involved in wing design are essential for understanding both the aerodynamics and evolution of insect flight. An insect wing consists of a three-dimensional skeletal network of relatively hard veins which are interconnected through thin membranous areas called cells. These structures consists of cuticle, a biological fibrous composite material, the mechanical properties of which may range from very stiff to flexible, depending on its chemical composition. This report summarises data on the presence of resilin, a rubber-like protein in the flexibly-joined junctions of wing veins. This protein is a substance which is responsible for elastic energy storage. Any folding of the distal wing parts can not be achieved by local muscles, but must be done by remote (thoracic) muscles or local elasticity. Many insects, such as earwigs and beetles, have developed complex mechanisms of wing folding, which are advantageous for insects living in soil or other narrow substrata. The folding pattern depends on the wing geometry, venation pattern, and material properties of structures involved. Thus, design of wings with folding functions has an additional complexity: their design is a kind of compromise between flight and folding. (orig.) [German] Biomechanische Systeme, in denen gummiartige Gelenke vorkommen, reichen von den Sprungsystemen von Kaefern, Floehen, Schaumzikaden und Heuschrecken bis Saugpumpen von Wanzen und Fliegen. Resilin ist ein elastisches Strukturprotein, dessen Name sich vom lateinischen Wort fuer 'zurueckschnellen' herleitet. Sein

  4. Preferred skin color enhancement for photographic color reproduction

    Science.gov (United States)

    Zeng, Huanzhao; Luo, Ronnier

    2011-01-01

    Skin tones are the most important colors among the memory color category. Reproducing skin colors pleasingly is an important factor in photographic color reproduction. Moving skin colors toward their preferred skin color center improves the color preference of skin color reproduction. Several methods to morph skin colors to a smaller preferred skin color region has been reported in the past. In this paper, a new approach is proposed to further improve the result of skin color enhancement. An ellipsoid skin color model is applied to compute skin color probabilities for skin color detection and to determine a weight for skin color adjustment. Preferred skin color centers determined through psychophysical experiments were applied for color adjustment. Preferred skin color centers for dark, medium, and light skin colors are applied to adjust skin colors differently. Skin colors are morphed toward their preferred color centers. A special processing is applied to avoid contrast loss in highlight. A 3-D interpolation method is applied to fix a potential contouring problem and to improve color processing efficiency. An psychophysical experiment validates that the method of preferred skin color enhancement effectively identifies skin colors, improves the skin color preference, and does not objectionably affect preferred skin colors in original images.

  5. Beneficial aerodynamic effect of wing scales on the climbing flight of butterflies.

    Science.gov (United States)

    Slegers, Nathan; Heilman, Michael; Cranford, Jacob; Lang, Amy; Yoder, John; Habegger, Maria Laura

    2017-01-30

    It is hypothesized that butterfly wing scale geometry and surface patterning may function to improve aerodynamic efficiency. In order to investigate this hypothesis, a method to measure butterfly flapping kinematics optically over long uninhibited flapping sequences was developed. Statistical results for the climbing flight flapping kinematics of 11 butterflies, based on a total of 236 individual flights, both with and without their wing scales, are presented. Results show, that for each of the 11 butterflies, the mean climbing efficiency decreased after scales were removed. Data was reduced to a single set of differences of climbing efficiency using are paired t-test. Results show a mean decrease in climbing efficiency of 32.2% occurred with a 95% confidence interval of 45.6%-18.8%. Similar analysis showed that the flapping amplitude decreased by 7% while the flapping frequency did not show a significant difference. Results provide strong evidence that butterfly wing scale geometry and surface patterning improve butterfly climbing efficiency. The authors hypothesize that the wing scale's effect in measured climbing efficiency may be due to an improved aerodynamic efficiency of the butterfly and could similarly be used on flapping wing micro air vehicles to potentially achieve similar gains in efficiency.

  6. Semi-automated quantitative Drosophila wings measurements.

    Science.gov (United States)

    Loh, Sheng Yang Michael; Ogawa, Yoshitaka; Kawana, Sara; Tamura, Koichiro; Lee, Hwee Kuan

    2017-06-28

    Drosophila melanogaster is an important organism used in many fields of biological research such as genetics and developmental biology. Drosophila wings have been widely used to study the genetics of development, morphometrics and evolution. Therefore there is much interest in quantifying wing structures of Drosophila. Advancement in technology has increased the ease in which images of Drosophila can be acquired. However such studies have been limited by the slow and tedious process of acquiring phenotypic data. We have developed a system that automatically detects and measures key points and vein segments on a Drosophila wing. Key points are detected by performing image transformations and template matching on Drosophila wing images while vein segments are detected using an Active Contour algorithm. The accuracy of our key point detection was compared against key point annotations of users. We also performed key point detection using different training data sets of Drosophila wing images. We compared our software with an existing automated image analysis system for Drosophila wings and showed that our system performs better than the state of the art. Vein segments were manually measured and compared against the measurements obtained from our system. Our system was able to detect specific key points and vein segments from Drosophila wing images with high accuracy.

  7. Novel Control Effectors for Truss Braced Wing

    Science.gov (United States)

    White, Edward V.; Kapania, Rakesh K.; Joshi, Shiv

    2015-01-01

    At cruise flight conditions very high aspect ratio/low sweep truss braced wings (TBW) may be subject to design requirements that distinguish them from more highly swept cantilevered wings. High aspect ratio, short chord length and relative thinness of the airfoil sections all contribute to relatively low wing torsional stiffness. This may lead to aeroelastic issues such as aileron reversal and low flutter margins. In order to counteract these issues, high aspect ratio/low sweep wings may need to carry additional high speed control effectors to operate when outboard ailerons are in reversal and/or must carry additional structural weight to enhance torsional stiffness. The novel control effector evaluated in this study is a variable sweep raked wing tip with an aileron control surface. Forward sweep of the tip allows the aileron to align closely with the torsional axis of the wing and operate in a conventional fashion. Aft sweep of the tip creates a large moment arm from the aileron to the wing torsional axis greatly enhancing aileron reversal. The novelty comes from using this enhanced and controllable aileron reversal effect to provide roll control authority by acting as a servo tab and providing roll control through intentional twist of the wing. In this case the reduced torsional stiffness of the wing becomes an advantage to be exploited. The study results show that the novel control effector concept does provide roll control as described, but only for a restricted class of TBW aircraft configurations. For the configuration studied (long range, dual aisle, Mach 0.85 cruise) the novel control effector provides significant benefits including up to 12% reduction in fuel burn.

  8. Nonlinear Structures Optimization for Flexible Flapping Wing MAVs

    Science.gov (United States)

    2009-02-01

    nonlinear optimization, flapping wing, fluid structure interaction, micro -air vehicles, flexible wing, flapping mechanism 16. SECURITY... Structures Optimization for Flexible Flapping Wing Micro -Air Vehicles” was funded with Chief Scientist Innovative Research funds. This project was divided...predict a 10% resisting load to the model, and Python Scripting to wrap around everything. 2 Building the Model in Abaqus CAE The flapping wing

  9. Generic Wing-Body Aerodynamics Data Base

    Science.gov (United States)

    Holst, Terry L.; Olsen, Thomas H.; Kwak, Dochan (Technical Monitor)

    2001-01-01

    The wing-body aerodynamics data base consists of a series of CFD (Computational Fluid Dynamics) simulations about a generic wing body configuration consisting of a ogive-circular-cylinder fuselage and a simple symmetric wing mid-mounted on the fuselage. Solutions have been obtained for Nonlinear Potential (P), Euler (E) and Navier-Stokes (N) solvers over a range of subsonic and transonic Mach numbers and angles of attack. In addition, each solution has been computed on a series of grids, coarse, medium and fine to permit an assessment of grid refinement errors.

  10. Unemployment and Right-Wing Extremist Crime

    OpenAIRE

    Falk, Armin; Zweimüller, Josef

    2005-01-01

    Right-wing extremism is a serious problem in many societies. A prominent hypothesis states that unemployment plays a crucial role for the occurrence of right-wing extremist crime. In this paper we empirically test this hypothesis. We use a previously not used data set which includes all officially recorded right-wing criminal acts in Germany. These data are recorded by the German Federal Criminal Police Office on a monthly and state level basis. Our main finding is that there is in fact a sig...

  11. Colored Contact Lens Dangers

    Medline Plus

    Full Text Available ... One Use Facts About Colored Contacts and Halloween Safety Colored Contact Lens Facts Over-the-Counter Costume ... new application of artificial intelligence shows whether a patient’s eyes point to high blood pressure or risk ...

  12. Colored Contact Lens Dangers

    Medline Plus

    Full Text Available ... use of colored contact lenses , from the U.S. Food and Drug Administration (FDA). Are the colored lenses ... 2018 By Dan T. Gudgel Do you know what the difference is between ophthalmologists and optometrists? A ...

  13. Colored Contact Lens Dangers

    Medline Plus

    Full Text Available ... with Colored Contact Lenses Julian: Teenager Blinded In One Eye By Non-Prescription Contact Lens Laura: Vision ... Robyn: Blurry Vision and Daily Eye Drops After One Use Facts About Colored Contacts and Halloween Safety ...

  14. Colored Contact Lens Dangers

    Medline Plus

    Full Text Available ... One Use Facts About Colored Contacts and Halloween Safety Colored Contact Lens Facts Over-the-Counter Costume ... Academy Jobs at the Academy Financial Relationships with Industry Medical Disclaimer Privacy Policy Terms of Service For ...

  15. Antibacterial Structural Color Hydrogels.

    Science.gov (United States)

    Chen, Zhuoyue; Mo, Min; Fu, Fanfan; Shang, Luoran; Wang, Huan; Liu, Cihui; Zhao, Yuanjin

    2017-11-08

    Structural color hydrogels with lasting survivability are important for many applications, but they still lack anti-biodegradation capability. Thus, we herein present novel antibacterial structural color hydrogels by simply integrating silver nanoparticles (AgNPs) in situ into the hydrogel materials. Because the integrated AgNPs possessed wide and excellent antibacterial abilities, the structural color hydrogels could prevent bacterial adhesion, avoid hydrogel damage, and maintain their vivid structural colors during their application and storage. It was demonstrated that the AgNP-tagged poly(N-isopropylacrylamide) structural color hydrogels could retain their original thermal-responsive color transition even when the AgNP-free hydrogels were degraded by bacteria and that the AgNP-integrated self-healing structural color protein hydrogels could save their self-repairing property instead of being degraded by bacteria. These features indicated that the antibacterial structural color hydrogels could be amenable to a variety of practical biomedical applications.

  16. Fingers that change color

    Science.gov (United States)

    Blanching of the fingers; Fingers - pale; Toes that change color; Toes - pale ... These conditions can cause fingers or toes to change color: Buerger disease. Chilblains. Painful inflammation of small ...

  17. Colored Contact Lens Dangers

    Medline Plus

    Full Text Available ... One Use Facts About Colored Contacts and Halloween Safety Colored Contact Lens Facts Over-the-Counter Costume ... an ophthalmologist — an eye medical doctor — who will measure each eye and talk to you about proper ...

  18. The wings of Bombyx mori develop from larval discs exhibiting an ...

    Indian Academy of Sciences (India)

    Unknown

    field and French 1999). We present here the expression pattern of Nubbin (Nub), Wingless (Wg) and Distal-less. (Dll) in B. mori wing discs using antibodies generated against the corresponding proteins from Drosophila or the butterfly P. coenia. The expression of Wg and Dll as overlapping domains in the distal region in B.

  19. Color and experiment

    International Nuclear Information System (INIS)

    Chanowitz, M.S.

    After a brief review of the color hypothesis and the motivations for its introduction, the experimental tests are discussed. Colored states are assumed not to have been produced at present energies and the only experimental tests discussed apply below the color threshold, when color is a 'hidden symmetry'. Some of these tests offer the posibility of distinguishing between quark models with fractional and integral quark charges

  20. Color and experimental physics

    International Nuclear Information System (INIS)

    Chanowitz, M.S.

    1975-01-01

    After a brief review of the color hypothesis and the motivations for its introduction, the experimental tests arare discussed. It is assumed that colored states have not been produced at present energies and only experimental tests which apply below the color threshold, when color is a ''hidden symmetry,'' are discussed. Some of these tests offer the possibility of distinguishing between quark models with fractional and integral quark charges. (auth)

  1. Progress in digital color workflow understanding in the International Color Consortium (ICC) Workflow WG

    Science.gov (United States)

    McCarthy, Ann

    2006-01-01

    The ICC Workflow WG serves as the bridge between ICC color management technologies and use of those technologies in real world color production applications. ICC color management is applicable to and is used in a wide range of color systems, from highly specialized digital cinema color special effects to high volume publications printing to home photography. The ICC Workflow WG works to align ICC technologies so that the color management needs of these diverse use case systems are addressed in an open, platform independent manner. This report provides a high level summary of the ICC Workflow WG objectives and work to date, focusing on the ways in which workflow can impact image quality and color systems performance. The 'ICC Workflow Primitives' and 'ICC Workflow Patterns and Dimensions' workflow models are covered in some detail. Consider the questions, "How much of dissatisfaction with color management today is the result of 'the wrong color transformation at the wrong time' and 'I can't get to the right conversion at the right point in my work process'?" Put another way, consider how image quality through a workflow can be negatively affected when the coordination and control level of the color management system is not sufficient.

  2. Plasmonic Colors: Toward Mass Production of Metasurfaces

    DEFF Research Database (Denmark)

    Højlund-Nielsen, Emil; Clausen, Jeppe Sandvik; Mäkela, Tapio

    2016-01-01

    in terms of master fabrication, replication, metallization, and protection coating for large-scale production of sub-wavelength metasurfaces are discussed. Most notably, it is demonstrated that plasmonic metasurface colors are compatible with fi lm insert molding. The results indicate a promising future......Plasmonic metasurface coloration has attracted considerable attention in recent years due to its industrial potential. So far, demonstrations have been limited to small patterned areas fabricated using expensive techniques with limited scalability. This study elevates the technology beyond...

  3. Did trichromatic color vision and red hair color coevolve in primates?

    Science.gov (United States)

    Kamilar, Jason M; Heesy, Christopher P; Bradley, Brenda J

    2013-07-01

    Reddish pelage and red hair ornaments have evolved many times, independently, during primate evolution. It is generally assumed that these red-coat phenotypes, like red skin phenotypes, play a role in sociosexual signaling and, thus evolved in tandem with conspecific color vision. This study examines the phylogenetic distribution of color vision and pelage coloration across the primate order to ask: (1) did red pelage and trichromacy coevolve; or (2) did trichromacy evolve first, and then subsequently red pelage evolved as an exaptation? We collected quantitative, color-corrected photographic color data for 142 museum research skins from 92 species representing 41 genera spanning all major primate lineages. For each species, we quantified the ratio of Red/Green values (from a RGB color model) at 20 anatomical landmarks. For these same species, we compiled data on color vision type (routine trichromatic, polymorphic, routine dichromatic, monochromatic) and data on variables that potentially covary with visual system (VS) and coloration, including activity pattern and body mass dimorphism (proxy for sexual selection). We also considered whether the long-term storage of research skins might influence coloration. Therefore, we included the time since the specimen was collected as an additional predictor. Analyzing the data with phylogenetic generalized least squares models, we found that the amount of red hair present in primates is associated with differences in VSs, but not in the direction expected. Surprisingly, trichromatic primate species generally exhibited less red hair compared to red-green colorblind species. Thus, our results do not support the general assumption that color vision and red pelage coloration are a coevolutionary product of sociosexual signaling in primates. In addition, we did not find an effect of activity pattern, body mass dimorphism, or time since collection on the redness of primate hair. Our results have important implications for the

  4. Reimagining the Color Wheel

    Science.gov (United States)

    Snyder, Jennifer

    2011-01-01

    Color wheels are a traditional project for many teachers. The author has used them in art appreciation classes for many years, but one problem she found when her pre-service art education students created colored wheels was that they were boring: simple circles, with pie-shaped pieces, which students either painted or colored in. This article…

  5. Colored Contact Lens Dangers

    Medline Plus

    Full Text Available ... in Cleveland. "This is far from the truth." Real People, Real Problems with Colored Contact Lenses Julian: Teenager Blinded ... use of colored contact lenses , from the U.S. Food and Drug Administration (FDA). Are the colored lenses ...

  6. Characterization of natural photonic crystals in iridescent wings of damselfly Chalcopteryx rutilans by FIB/SEM, TEM, and TOF-SIMS.

    Science.gov (United States)

    Carr, David M; Ellsworth, Ashley A; Fisher, Gregory L; Valeriano, Wescley W; Vasco, Juan P; Guimarães, Paulo S S; de Andrade, Rodrigo R; da Silva, Elizabeth R; Rodrigues, Wagner N

    2018-02-05

    The iridescent wings of the Chalcopterix rutilans damselfly (Rambur) (Odonata, Polythoridae) are investigated with focused ion beam/scanning electron microscopy, transmission electron microscopy, and time-of-flight secondary ion mass spectrometry. The electron microscopy images reveal a natural photonic crystal as the source of the varying colors. The photonic crystal has a consistent number and thickness (∼195 nm) of the repeat units on the ventral side of the wing, which is consistent with the red color visible from the bottom side of the wing in all regions. The dorsal side of the wing shows strong color variations ranging from red to blue depending on the region. In the electron microscopy images, the dorsal side of the wing exhibits varied number and thicknesses of the repeat units. The repeat unit spacings for the red, yellow/green, and blue regions are approximately 195, 180, and 145 nm, respectively. Three-dimensional analysis of the natural photonic crystals by time-of-flight secondary ion mass spectrometry reveals that changes in the relative levels of Na, K, and eumelanin are responsible for the varying dielectric constant needed to generate the photonic crystal. The photonic crystal also appears to be assembled with a chemical tricomponent layer structure due to the enhancement of the CH 6 N 3 + species at every other interface between the high/low dielectric constant layers.

  7. The leading-edge vortex of swift-wing shaped delta wings

    Science.gov (United States)

    Muir, Rowan; Arredondo-Galeana, Abel; Viola, Ignazio Maria

    2017-11-01

    Recent investigations on the aerodynamics of natural fliers have illuminated the significance of the Leading-Edge Vortex (LEV) for lift generation in a variety of flight conditions. In this investigation, a model non-slender delta shaped wing with a sharp leading-edge is tested at low Reynolds Number, along with a delta wing of the same design, but with a modified trailing edge inspired by the wing of a common swift Apus apus. The effect of the tapering swift wing on LEV development and stability is compared with the flow structure over the un-modified delta wing model through particle image velocimetry. For the first time, a leading-edge vortex system consisting of a dual or triple LEV is recorded on a swift-wing shaped delta wing, where such a system is found across all tested conditions. It is shown that the spanwise location of LEV breakdown is governed by the local chord rather than Reynolds Number or angle of attack. These findings suggest that the trailing-edge geometry of the swift wing alone does not prevent the common swift from generating an LEV system comparable with that of a delta shaped wing. This work received funding from the Engineering and Physical Sciences Research Council [EP/M506515/1] and the Consejo Nacional de Ciencia y Tecnología (CONACYT).

  8. Fruit fly scale robots can hover longer with flapping wings than with spinning wings.

    Science.gov (United States)

    Hawkes, Elliot W; Lentink, David

    2016-10-01

    Hovering flies generate exceptionally high lift, because their wings generate a stable leading edge vortex. Micro flying robots with a similar wing design can generate similar high lift by either flapping or spinning their wings. While it requires less power to spin a wing, the overall efficiency depends also on the actuator system driving the wing. Here, we present the first holistic analysis to calculate how long a fly-inspired micro robot can hover with flapping versus spinning wings across scales. We integrate aerodynamic data with data-driven scaling laws for actuator, electronics and mechanism performance from fruit fly to hummingbird scales. Our analysis finds that spinning wings driven by rotary actuators are superior for robots with wingspans similar to hummingbirds, yet flapping wings driven by oscillatory actuators are superior at fruit fly scale. This crossover is driven by the reduction in performance of rotary compared with oscillatory actuators at smaller scale. Our calculations emphasize that a systems-level analysis is essential for trading-off flapping versus spinning wings for micro flying robots. © 2016 The Author(s).

  9. Flow Modulation and Force Control of Flapping Wings

    Science.gov (United States)

    2014-10-29

    tested on a flapping wing model in the oil tank. Robotic flapper equipped with DC motors drove the wing model, and the imbedded servo motor could flap...the overall wake structure on the hovering wings. Totally, two volumetric flow measurements were performed on two mechanical flappers with different...wing kinematics but similar wing geometry. On the flappers with small stroke angle and passive rotation, the general vortex wake structure

  10. Left-Wing Extremism: The Current Threat

    Energy Technology Data Exchange (ETDEWEB)

    Karl A. Seger

    2001-04-30

    Left-wing extremism is ''alive and well'' both in the US and internationally. Although the current domestic terrorist threat within the U. S. is focused on right-wing extremists, left-wing extremists are also active and have several objectives. Leftist extremists also pose an espionage threat to U.S. interests. While the threat to the U.S. government from leftist extremists has decreased in the past decade, it has not disappeared. There are individuals and organizations within the U.S. who maintain the same ideology that resulted in the growth of left-wing terrorism in this country in the 1970s and 1980s. Some of the leaders from that era are still communicating from Cuba with their followers in the U.S., and new leaders and groups are emerging.

  11. A galactic microquasar mimicking winged radio galaxies.

    Science.gov (United States)

    Martí, Josep; Luque-Escamilla, Pedro L; Bosch-Ramon, Valentí; Paredes, Josep M

    2017-11-24

    A subclass of extragalactic radio sources known as winged radio galaxies has puzzled astronomers for many years. The wing features are detected at radio wavelengths as low-surface-brightness radio lobes that are clearly misaligned with respect to the main lobe axis. Different models compete to account for these peculiar structures. Here, we report observational evidence that the parsec-scale radio jets in the Galactic microquasar GRS 1758-258 give rise to a Z-shaped radio emission strongly reminiscent of the X and Z-shaped morphologies found in winged radio galaxies. This is the first time that such extended emission features are observed in a microquasar, providing a new analogy for its extragalactic relatives. From our observations, we can clearly favour the hydrodynamic backflow interpretation against other possible wing formation scenarios. Assuming that physical processes are similar, we can extrapolate this conclusion and suggest that this mechanism could also be at work in many extragalactic cases.

  12. Molecular basis and ecological relevance of aphid body colors.

    Science.gov (United States)

    Tsuchida, Tsutomu

    2016-10-01

    Aphids are small phloem sap-feeding insects, and show color polymorphism even within the same species. Crossing experiments have revealed the inheritance pattern of the body color. Coloration of aphids is determined by mainly three pigments, melanin, carotenoid, and aphin, and is influenced by both abiotic and biotic environmental factors. Aphid body colors also seem to correspond with specific biological functions under various environments. Partly due to the presence of natural enemies in the environment, a variety of physiological and behavioral responses have evolved in each color form. Thus, predation is one of the most significant external factors for maintaining body color polymorphisms. In addition, endosymbiont infections also influence aphid body color and prey-predator interactions. However, many unsolved questions remain regarding the molecular basis for and biological functions of aphid body colors. Further work, including the development of molecular techniques for comprehensive functional analysis, is needed in these areas. Copyright © 2016 Elsevier Inc. All rights reserved.

  13. Uniform color spaces and natural image statistics.

    Science.gov (United States)

    McDermott, Kyle C; Webster, Michael A

    2012-02-01

    Many aspects of visual coding have been successfully predicted by starting from the statistics of natural scenes and then asking how the stimulus could be efficiently represented. We started from the representation of color characterized by uniform color spaces, and then asked what type of color environment they implied. These spaces are designed to represent equal perceptual differences in color discrimination or appearance by equal distances in the space. The relative sensitivity to different axes within the space might therefore reflect the gamut of colors in natural scenes. To examine this, we projected perceptually uniform distributions within the Munsell, CIE L(*)u(*)v(*) or CIE L(*)a(*)b(*) spaces into cone-opponent space. All were elongated along a bluish-yellowish axis reflecting covarying signals along the L-M and S-(L+M) cardinal axes, a pattern typical (though not identical) to many natural environments. In turn, color distributions from environments were more uniform when projected into the CIE L(*)a(*)b(*) perceptual space than when represented in a normalized cone-opponent space. These analyses suggest the bluish-yellowish bias in environmental colors might be an important factor shaping chromatic sensitivity, and also suggest that perceptually uniform color metrics could be derived from natural scene statistics and potentially tailored to specific environments. © 2012 Optical Society of America

  14. Iridescence and spectral filtering of the gyroid-type photonic crystals in Parides sesostris wing scales

    Science.gov (United States)

    Wilts, Bodo D.; Michielsen, Kristel; De Raedt, Hans; Stavenga, Doekele G.

    2012-01-01

    The cover scales on the wing of the Emerald-patched Cattleheart butterfly, Parides sesostris, contain gyroid-type biological photonic crystals that brightly reflect green light. A pigment, which absorbs maximally at approximately 395 nm, is immersed predominantly throughout the elaborate upper lamina. This pigment acts as a long-pass filter shaping the reflectance spectrum of the underlying photonic crystals. The additional effect of the filtering is that the spatial distribution of the scale reflectance is approximately angle-independent, leading to a stable wing pattern contrast. The spectral tuning of the original reflectance is verified by photonic band structure modelling. PMID:24098853

  15. Scanning Color Laser Microscope

    Science.gov (United States)

    Awamura, D.; Ode, T.; Yonezawa, M.

    1988-01-01

    A confocal color laser microscope which utilizes a three color laser light source (Red: He-Ne, Green: Ar, Blue: Ar) has been developed and is finding useful applications in the semiconductor field. The color laser microscope, when compared to a conventional microscope, offers superior color separation, higher resolution, and sharper contrast. Recently some new functions including a Focus Scan Memory, a Surface Profile Measurement System, a Critical Dimension Measurement system (CD) and an Optical Beam Induced Current Function (OBIC) have been developed for the color laser microscope. This paper will discuss these new features.

  16. Relating color working memory and color perception.

    Science.gov (United States)

    Allred, Sarah R; Flombaum, Jonathan I

    2014-11-01

    Color is the most frequently studied feature in visual working memory (VWM). Oddly, much of this work de-emphasizes perception, instead making simplifying assumptions about the inputs served to memory. We question these assumptions in light of perception research, and we identify important points of contact between perception and working memory in the case of color. Better characterization of its perceptual inputs will be crucial for elucidating the structure and function of VWM. Copyright © 2014 Elsevier Ltd. All rights reserved.

  17. The leading-edge vortex of swift wing-shaped delta wings.

    Science.gov (United States)

    Muir, Rowan Eveline; Arredondo-Galeana, Abel; Viola, Ignazio Maria

    2017-08-01

    Recent investigations on the aerodynamics of natural fliers have illuminated the significance of the leading-edge vortex (LEV) for lift generation in a variety of flight conditions. A well-documented example of an LEV is that generated by aircraft with highly swept, delta-shaped wings. While the wing aerodynamics of a manoeuvring aircraft, a bird gliding and a bird in flapping flight vary significantly, it is believed that this existing knowledge can serve to add understanding to the complex aerodynamics of natural fliers. In this investigation, a model non-slender delta-shaped wing with a sharp leading edge is tested at low Reynolds number, along with a delta wing of the same design, but with a modified trailing edge inspired by the wing of a common swift Apus apus . The effect of the tapering swift wing on LEV development and stability is compared with the flow structure over the unmodified delta wing model through particle image velocimetry. For the first time, a leading-edge vortex system consisting of a dual or triple LEV is recorded on a swift wing-shaped delta wing, where such a system is found across all tested conditions. It is shown that the spanwise location of LEV breakdown is governed by the local chord rather than Reynolds number or angle of attack. These findings suggest that the trailing-edge geometry of the swift wing alone does not prevent the common swift from generating an LEV system comparable with that of a delta-shaped wing.

  18. The color enhancement and collimation features of the multi-colored LEDs with different periodic microstructure on the top surface of TIR lens

    Science.gov (United States)

    Ying, Shang-Ping; Fu, Han-Kuei

    2017-09-01

    Due to the advantages, such as high efficiency, power consumption reduction, no mercury, pure saturated color, high reliability and long lifetime, the solid-state lighting based on light-emitting diodes (LEDs) has become very popular at this stage. In the lighting applications such as spot lighting, downlighting, architectural and show lighting, the colortunable properties with collimating beam of LEDs are highly demanded. The color-tunable lighting is easily achieved using multi-colored LEDs instead of inefficient color filters. However, the applications of multi-colored LEDs usually appear the undesirable light patterns such as color separation or color fringes. At the meantime, the use of TIR (total internal reflection) lens for multi-colored LEDs to collimate the light from the LEDs with different color will introduce seriously undesirable artifacts. Thus, a periodic microstructure surface on the top surface of the TIR lens would be used to reshape the light from the different colored LED chips in the multi-colored LEDs, and then decrease the color separation and color nonuniformity. In this study, the TIR lens with periodic microstructure surface on the top surface would be used to collimate the light from multi-colored LEDs with low color separation or color fringes. The analysis of color enhancement and collimation features of the multi-colored LEDs with different periodic microstructure on the top surface of the TIR lens is presented.

  19. Numerical and experimental investigations on unsteady aerodynamics of flapping wings

    Science.gov (United States)

    Yu, Meilin

    suggestions to the design of micro-air-vehicles (MAVs), 3D simulations of the flapping wings are carried out in this work. Both the rectangular and bio-inspired wings with different kinematics are investigated. The formation process of two-jet-like wake patterns behind the finite-span flapping wing is found to be closely related to the interaction between trailing edge vortices and tip vortices. Then the effects of the wing planforms on the aerodynamics performance of the finite-span flapping wings are elucidated in terms of the evolution and dynamic interaction of unsteady vortex structures.

  20. Colors, colored overlays, and reading skills

    Directory of Open Access Journals (Sweden)

    Arcangelo eUccula

    2014-07-01

    Full Text Available In this article, we are concerned with the role of colors in reading written texts. It has been argued that colored overlays applied above written texts positively influence both reading fluency and reading speed. These effects would be particularly evident for those individuals affected by the so called Meares-Irlen syndrome, i.e. who experience eyestrain and/or visual distortions – e.g. color, shape or movement illusions – while reading. This condition would interest the 12-14% of the general population and up to the 46% of the dyslexic population. Thus, colored overlays have been largely employed as a remedy for some aspects of the difficulties in reading experienced by dyslexic individuals, as fluency and speed. Despite the wide use of colored overlays, how they exert their effects has not been made clear yet. Also, according to some researchers, the results supporting the efficacy of colored overlays as a tool for helping readers are at least controversial. Furthermore, the very nature of the Meares-Irlen syndrome has been questioned. Here we provide a concise, critical review of the literature.

  1. WHY COLOR-FLAVOR LOCKING IS JUST LIKE CHIRAL SYMMETRY BREAKING

    International Nuclear Information System (INIS)

    PISARSKI, R.D.; RISCHKE, D.H.

    2000-01-01

    The authors review how a classification into representations of color and flavor can be used to understand the possible patterns of symmetry breaking for color superconductivity in dense quark matter. In particular, the authors show how for three flavors, color-flavor locking is precisely analogous to the usual pattern of chiral symmetry breaking in the QCD vacuum

  2. Dpp spreading is required for medial but not for lateral wing disc growth.

    Science.gov (United States)

    Harmansa, Stefan; Hamaratoglu, Fisun; Affolter, Markus; Caussinus, Emmanuel

    2015-11-19

    Drosophila Decapentaplegic (Dpp) has served as a paradigm to study morphogen-dependent growth control. However, the role of a Dpp gradient in tissue growth remains highly controversial. Two fundamentally different models have been proposed: the 'temporal rule' model suggests that all cells of the wing imaginal disc divide upon a 50% increase in Dpp signalling, whereas the 'growth equalization model' suggests that Dpp is only essential for proliferation control of the central cells. Here, to discriminate between these two models, we generated and used morphotrap, a membrane-tethered anti-green fluorescent protein (GFP) nanobody, which enables immobilization of enhanced (e)GFP::Dpp on the cell surface, thereby abolishing Dpp gradient formation. We find that in the absence of Dpp spreading, wing disc patterning is lost; however, lateral cells still divide at normal rates. These data are consistent with the growth equalization model, but do not fit a global temporal rule model in the wing imaginal disc.

  3. Color Reproduction with a Smartphone

    Science.gov (United States)

    Thoms, Lars-Jochen; Colicchia, Giuseppe; Girwidz, Raimund

    2013-01-01

    The world is full of colors. Most of the colors we see around us can be created on common digital displays simply by superposing light with three different wavelengths. However, no mixture of colors can produce a fully pure color identical to a spectral color. Using a smartphone, students can investigate the main features of primary color addition…

  4. Aeroelasticity of morphing wings using neural networks

    Science.gov (United States)

    Natarajan, Anand

    In this dissertation, neural networks are designed to effectively model static non-linear aeroelastic problems in adaptive structures and linear dynamic aeroelastic systems with time varying stiffness. The use of adaptive materials in aircraft wings allows for the change of the contour or the configuration of a wing (morphing) in flight. The use of smart materials, to accomplish these deformations, can imply that the stiffness of the wing with a morphing contour changes as the contour changes. For a rapidly oscillating body in a fluid field, continuously adapting structural parameters may render the wing to behave as a time variant system. Even the internal spars/ribs of the aircraft wing which define the wing stiffness can be made adaptive, that is, their stiffness can be made to vary with time. The immediate effect on the structural dynamics of the wing, is that, the wing motion is governed by a differential equation with time varying coefficients. The study of this concept of a time varying torsional stiffness, made possible by the use of active materials and adaptive spars, in the dynamic aeroelastic behavior of an adaptable airfoil is performed here. Another type of aeroelastic problem of an adaptive structure that is investigated here, is the shape control of an adaptive bump situated on the leading edge of an airfoil. Such a bump is useful in achieving flow separation control for lateral directional maneuverability of the aircraft. Since actuators are being used to create this bump on the wing surface, the energy required to do so needs to be minimized. The adverse pressure drag as a result of this bump needs to be controlled so that the loss in lift over the wing is made minimal. The design of such a "spoiler bump" on the surface of the airfoil is an optimization problem of maximizing pressure drag due to flow separation while minimizing the loss in lift and energy required to deform the bump. One neural network is trained using the CFD code FLUENT to

  5. The spectral density of the QCD Dirac operator and patterns of chiral symmetry breaking

    International Nuclear Information System (INIS)

    Toublan, D.; Verbaarschot, J.J.M.

    1999-01-01

    We study the spectrum of the QCD Dirac operator for two colors with fermions in the fundamental representation and for two or more colors with adjoint fermions. For N f flavors, the chiral flavor symmetry of these theories is spontaneously broken according to SU (2N f → Sp (2N f ) and SU (N f → O (N f ), respectively, rather than the symmetry breaking pattern SU (N f ) x SU (N f ) → SU (N f ) for QCD with three or more colors and fundamental fermions. In this paper we study the Dirac spectrum for the first two symmetry breaking patterns. Following previous work for the third case we find the Dirac spectrum in the domain λ QCD by means of partially quenched chiral perturbation theory. In particular, this result allows us to calculate the slope of the Dirac spectrum at λ = 0. We also show that for λ 2 Λ QCD (wing L the linear size of the system) the Dirac spectrum is given by a chiral Random Matrix Theory with the symmetries of the Dirac operator

  6. Hovering hummingbird wing aerodynamics during the annual cycle. I. Complete wing.

    Science.gov (United States)

    Achache, Yonathan; Sapir, Nir; Elimelech, Yossef

    2017-08-01

    The diverse hummingbird family (Trochilidae) has unique adaptations for nectarivory, among which is the ability to sustain hover-feeding. As hummingbirds mainly feed while hovering, it is crucial to maintain this ability throughout the annual cycle-especially during flight-feather moult, in which wing area is reduced. To quantify the aerodynamic characteristics and flow mechanisms of a hummingbird wing throughout the annual cycle, time-accurate aerodynamic loads and flow field measurements were correlated over a dynamically scaled wing model of Anna's hummingbird ( Calypte anna ). We present measurements recorded over a model of a complete wing to evaluate the baseline aerodynamic characteristics and flow mechanisms. We found that the vorticity concentration that had developed from the wing's leading-edge differs from the attached vorticity structure that was typically found over insects' wings; firstly, it is more elongated along the wing chord, and secondly, it encounters high levels of fluctuations rather than a steady vortex. Lift characteristics resemble those of insects; however, a 20% increase in the lift-to-torque ratio was obtained for the hummingbird wing model. Time-accurate aerodynamic loads were also used to evaluate the time-evolution of the specific power required from the flight muscles, and the overall wingbeat power requirements nicely matched previous studies.

  7. Color balancing in CCD color cameras using analog signal processors made by Kodak

    Science.gov (United States)

    Kannegundla, Ram

    1995-03-01

    The green, red, and blue color filters used for CCD sensors generally have different responses. It is often necessary to balance these three colors for displaying a high-quality image on the monitor. The color filter arrays on sensors have different architectures. A CCD with standard G R G B pattern is considered for the present discussion. A simple method of separating the colors using CDS/H that is a part of KASPs (Analog Signal Processors made by Kodak) and using the gain control, which is also a part of KASPs for color balance, is presented. The colors are separated from the video output of sensor by using three KASPs, one each for green, red, and blue colors and by using alternate sample pulses for green and 1 in 4 pulses for red and blue. The separated colors gain is adjusted either automatically or manually and sent to the monitor for direct display in the analog mode or through an A/D converter digitally to the memory. This method of color balancing demands high-quality ASPs. Kodak has designed four different chips with varying levels of power consumption and speed for analog signal processing of video output of CCD sensors. The analog ASICs have been characterized for noise, clock feedthrough, acquisition time, linearity, variable gain, line rate clamp, black muxing, affect of temperature variations on chip performance, and droop. The ASP chips have met their design specifications.

  8. Optical characterization of iridescent wings of butterflies using multilayer rigorous coupled wave analysis

    Science.gov (United States)

    Liao, Guanglan; Cao, Yanbo; Shi, Tielin; Zuo, Haibo; Peng, Ping; Tang, Zirong

    2008-12-01

    In certain species of moths and butterflies iridescent colors arise from sub-wavelength diffractive surface corrugation of the wing-scales. The optical properties of such structures depend strongly on the wavelength, the incidence angle, the polarization of illuminating radiation, and the index of ambient medium. In this paper, after getting the SEM picture of the dorsal scales of the Morpho didius butterfly, we construct a bionic two dimension model, whose ridge contains a certain quasi-periodic arrangement of tree-like sub-wavelength microstructures. Then using a multilayer rigorous coupled wave analysis method in two dimensions, we study the reflection spectra of the wings of Morpho didius butterfly by simulating the multilayer model of a transverse cross-section comprised of the ground scale. Here we assume that the structure is made of a slightly lossy dielectric material and analyzed the polarization, the incidence angle and the index of ambient medium which affect the reflection spectra strongly. The results got, have revealed the natural phenomenon of iridescent colors and color-changed in essence, and the simulation results enable an artificial microsensor which discriminate vapor or component by reflective efficiency spectra.

  9. The effects of wing flexibility on the flight performance and stability of flapping wing micro air vehicles

    Science.gov (United States)

    Bluman, James Edward

    Insect wings are flexible. However, the influence of wing flexibility on the flight dynamics of insects and flapping wing micro air vehicles is unknown. Most studies in the literature consider rigid wings and conclude that the hover equilibrium is unstable. This dissertation shows that a flapping wing flyer with flexible wings exhibits stable natural modes of the open loop system in hover, never reported before. The free-flight insect flight dynamics is modeled for both flexible and rigid wings. Wing mass and inertia are included in the nonlinear equations of motion. The flapping wing aerodynamics are modeled using a quasi-steady model, a well-validated two dimensional Navier Stokes model, and a coupled, two dimensional Navier Stokes - Euler Bernoulli beam model that accurately models the fluid-structure interaction of flexible wings. Hover equilibrium is systematically and efficiently determined with a coupled quasi-steady and Navier-Stokes equation trimmer. The power and stability are reported at hover while parametrically varying the pitch axis location for rigid wings and the structural stiffness for flexible wings. The results indicate that the rigid wings possess an unstable oscillatory mode mainly due to their pitch sensitivity to horizontal velocity perturbations. The flexible wings stabilize this mode primarily by adjusting their wing shape in the presence of perturbations. The wing's response to perturbations generates significantly more horizontal velocity damping and pitch rate damping than in rigid wings. Furthermore, the flexible wings experience substantially less wing wake interaction, which, for rigid wings, is destabilizing. The power required to hover a fruit fly with actively rotating rigid wings varies between 16.9 and 34.2 W/kg. The optimal power occurs when the pitch axis is located at 30% chord, similar to some biological observations. Flexible wings require 23.1 to 38.5 W/kg. However, flexible wings exhibit more stable system dynamics and

  10. Realtime Color Stereovision Processing

    National Research Council Canada - National Science Library

    Formwalt, Bryon

    2000-01-01

    .... This research takes a step forward in real time machine vision processing. It investigates techniques for implementing a real time stereovision processing system using two miniature color cameras...

  11. Online color monitoring

    Science.gov (United States)

    Massen, Robert C.

    1999-09-01

    Monitoring color in the production line requires to remotely observe moving and not-aligned objects with in general complex surface features: multicolored, textured, non-flat, showing highlights and shadows. We discuss the use of color cameras and associated color image processing technologies for what we call 'imaging colorimetry.' This is a 2-step procedure which first uses color for segmentation and for finding Regions-of- Interest on the moving objects and then uses cluster-based color image processing for computing color deviations relative to previously trained references. This colorimetry is much more a measurement of aesthetic consistency of the visual appearance of a product then the traditional measurement of a more physically defined mean color vector difference. We show how traditional non-imaging colorimetry looses most of this aesthetic information due to the computation of a mean color vector or mean color vector difference, by averaging over the sensor's field-of-view. A large number of industrial applications are presented where complex inspection tasks have been solved based on this approach. The expansion to a higher feature space dimensions based on the 'multisensorial camera' concept gives an outlook to future developments.

  12. Colors in kindergarten software

    Directory of Open Access Journals (Sweden)

    Montell, Ireivys

    2012-01-01

    Full Text Available The article aims to address elements related to the use of color in educational software for early ages. The meaning of colors in pre-school age is presented from a theoretical perspective. A psychoeducational assessment of the influence of colors in educational software as a teaching aid to develop general intellectual abilities is explained. Likewise, the paper explains how achieving a balance between colors and software design leads to a proper interaction of children with new technology, a new resource for achieving objectives in educations and stimulating cognitive process development, both in institutions and in non-institutional channels.

  13. [Wing 1 radiation survey and contamination report

    International Nuclear Information System (INIS)

    Olsen, K.

    1991-01-01

    We have completed the 5480.11 survey for Wing 1. All area(s)/item(s) requested by the 5480.11 committee have been thoroughly surveyed and documented. Decontamination/disposal of contaminated items has been accomplished. The wing 1 survey was started on 8/13/90 and completed 9/18/90. However, the follow-up surveys were not completed until 2/18/91. We received the final set of smear samples for wing 1 on 1/13/91. A total of 5,495 smears were taken from wing 1 and total of 465 smears were taken during the follow-up surveys. There were a total 122 items found to have fixed contamination and 4 items with smearable contamination in excess of the limits specified in DOE ORDER 5480.11 (AR 3-7). The following area(s)/item(s) were not included in the 5480.11 survey: Hallways, Access panels, Men's and women's change rooms, Janitor closets, Wall lockers and item(s) stored in wing 1 hallways and room 1116. If our contract is renewed, we will include those areas in our survey according to your request of April 15, 1991

  14. Flapping wing aerodynamics: from insects to vertebrates.

    Science.gov (United States)

    Chin, Diana D; Lentink, David

    2016-04-01

    More than a million insects and approximately 11,000 vertebrates utilize flapping wings to fly. However, flapping flight has only been studied in a few of these species, so many challenges remain in understanding this form of locomotion. Five key aerodynamic mechanisms have been identified for insect flight. Among these is the leading edge vortex, which is a convergent solution to avoid stall for insects, bats and birds. The roles of the other mechanisms - added mass, clap and fling, rotational circulation and wing-wake interactions - have not yet been thoroughly studied in the context of vertebrate flight. Further challenges to understanding bat and bird flight are posed by the complex, dynamic wing morphologies of these species and the more turbulent airflow generated by their wings compared with that observed during insect flight. Nevertheless, three dimensionless numbers that combine key flow, morphological and kinematic parameters - the Reynolds number, Rossby number and advance ratio - govern flapping wing aerodynamics for both insects and vertebrates. These numbers can thus be used to organize an integrative framework for studying and comparing animal flapping flight. Here, we provide a roadmap for developing such a framework, highlighting the aerodynamic mechanisms that remain to be quantified and compared across species. Ultimately, incorporating complex flight maneuvers, environmental effects and developmental stages into this framework will also be essential to advancing our understanding of the biomechanics, movement ecology and evolution of animal flight. © 2016. Published by The Company of Biologists Ltd.

  15. Advanced technology development multi-color holography

    Science.gov (United States)

    Vikram, Chandra S.

    1994-01-01

    Several key aspects of multi-color holography and some non-conventional ways to study the holographic reconstructions are considered. The error analysis of three-color holography is considered in detail with particular example of a typical triglycine sulfate crystal growth situation. For the numerical analysis of the fringe patterns, a new algorithm is introduced with experimental verification using sugar-water solution. The role of the phase difference among component holograms is also critically considered with examples of several two- and three-color situations. The status of experimentation on two-color holography and fabrication of a small breadboard system is also reported. Finally, some successful demonstrations of unconventional ways to study holographic reconstructions are described. These methods are deflectometry and confocal optical processing using some Spacelab III holograms.

  16. Color coherence in W + jet events

    International Nuclear Information System (INIS)

    Abbott, B.

    1997-11-01

    We report on preliminary studies of color coherence effects in p anti p collisions, based on data collected by the D0 detector during the 1994-1995 run of the Fermilab Tevatron collider, at a center of mass energy √s = 1.8 TeV. Color interference effects are studied by examining particle distribution patterns in W + Jet events. The data are compared to Monte Carlo simulations with different color coherence implementations and to a recent analytic Modified-Leading-Log perturbative calculation based on the Local Parton-Hadron Duality hypothesis. Soft particle radiation is enhanced in the event plane relative to the transverse plane, in agreement with calculations in which the effects of color coherence are fully included

  17. Fillers in the skin of color population.

    Science.gov (United States)

    Heath, Candrice R; Taylor, Susan C

    2011-05-01

    The skin of color population in the United States is rapidly growing and the cosmetic industry is responding to the demand for skin of color targeted treatments. The aging face in skin of color patients has a unique pattern that can be successfully augmented by dermal fillers. Though many subjects with skin of color were not included in the pre-market dermal filler clinical trials, some post-market studies have examined the safety and risks of adverse events in this population. The safety data from a selection of these studies was examined. Though pigmentary changes occurred, there have been no reports of keloid development. Developing a patient-specific care plan and instituting close follow up is emphasized.

  18. Principle of bio-inspired insect wing rotational hinge design

    Science.gov (United States)

    Fei, Fan

    A principle for designing and fabricating bio-inspired miniature artificial insect flapping wing using flexure rotational hinge design is presented. A systematic approach of selecting rotational hinge stiffness value is proposed. Based on the understanding of flapping wing aerodynamics, a dynamic simulation is constructed using the established quasi-steady model and the wing design. Simulations were performed to gain insight on how different parameters affect the wing rotational response. Based on system resonance a model to predict the optimal rotational hinge stiffness based on given wing parameter and flapping wing kinematic is proposed. By varying different wing parameters, the proposed method is shown to be applicable to a wide range of wing designs with different sizes and shapes. With the selected hinge stiffness value, aspects of the rotational joint design is discussed and an integrated wing-hinge structure design using laminated carbon fiber and polymer film is presented. Manufacturing process of such composite structure is developed to achieve high accuracy and repeatability. The yielded hinge stiffness is verified by measurements. To validate the proposed model, flapping wing experiments were conducted. A flapping actuation set up is built using DC motor and a controller is implemented on a microcontroller to track desired wing stroke kinematic. Wing stroke and rotation kinematic were extracted using a high speed camera and the lift generation is evaluated. A total of 49 flapping experiments were presented, experimental data shows good correlation with the model's prediction. With the wing rotational hinge stiffness designed so that the rotational resonant frequency is twice as the stroke frequency, the resulting wing rotation generates near optimal lift. With further simulation, the proposed model shows low sensitivity to wing parameter variation. As a result, giving a design parameter of a flapping wing robot platform, the proposed principle can

  19. Gliding swifts attain laminar flow over rough wings.

    Directory of Open Access Journals (Sweden)

    David Lentink

    Full Text Available Swifts are among the most aerodynamically refined gliding birds. However, the overlapping vanes and protruding shafts of their primary feathers make swift wings remarkably rough for their size. Wing roughness height is 1-2% of chord length on the upper surface--10,000 times rougher than sailplane wings. Sailplanes depend on extreme wing smoothness to increase the area of laminar flow on the wing surface and minimize drag for extended glides. To understand why the swift does not rely on smooth wings, we used a stethoscope to map laminar flow over preserved wings in a low-turbulence wind tunnel. By combining laminar area, lift, and drag measurements, we show that average area of laminar flow on swift wings is 69% (n = 3; std 13% of their total area during glides that maximize flight distance and duration--similar to high-performance sailplanes. Our aerodynamic analysis indicates that swifts attain laminar flow over their rough wings because their wing size is comparable to the distance the air travels (after a roughness-induced perturbation before it transitions from laminar to turbulent. To interpret the function of swift wing roughness, we simulated its effect on smooth model wings using physical models. This manipulation shows that laminar flow is reduced and drag increased at high speeds. At the speeds at which swifts cruise, however, swift-like roughness prolongs laminar flow and reduces drag. This feature gives small birds with rudimentary wings an edge during the evolution of glide performance.

  20. Luminance contours can gate afterimage colors and "real" colors.

    Science.gov (United States)

    Anstis, Stuart; Vergeer, Mark; Van Lier, Rob

    2012-09-06

    It has long been known that colored images may elicit afterimages in complementary colors. We have already shown (Van Lier, Vergeer, & Anstis, 2009) that one and the same adapting image may result in different afterimage colors, depending on the test contours presented after the colored image. The color of the afterimage depends on two adapting colors, those both inside and outside the test. Here, we further explore this phenomenon and show that the color-contour interactions shown for afterimage colors also occur for "real" colors. We argue that similar mechanisms apply for both types of stimulation.

  1. Two-color double exposure photographic recording technique

    Science.gov (United States)

    Stricker, Josef

    1989-01-01

    A two-color double exposure technique is proposed for recording two close states of an object on the same photographic film. The idea is to use a two-color laser for illumination, one color for each state of the object, and a single photographic plate. After being developed, the image of each state may be observed separately. The technique is demonstrated for the deferred moire deflectometry where two closely displaced fringe patterns have to be recorded and resolved.

  2. Color change and camouflage in juvenile shore crabs Carcinus maenas

    OpenAIRE

    Stevens, Martin; Lown, Alice E.; Wood, Louisa E.

    2014-01-01

    Camouflage is perhaps the most widespread anti-predator defense in nature, with many different types thought to exist. Of these, resembling the general color and pattern of the background (background matching) is likely to be the most common. Background matching can be achieved by adaptation of individual appearance to different habitats or substrates, behavioral choice, and color change. Although the ability to change coloration for camouflage over a period of hours or days is likely to be w...

  3. Encyclopedia of color science and technology

    CERN Document Server

    2016-01-01

    The Encyclopedia of Color Science and Technology provides an authoritative single source for understanding and applying the concepts of color to all fields of science and technology, including artistic and historical aspects of color. Many topics are discussed in this timely reference, including an introduction to the science of color, and entries on the physics, chemistry and perception of color. Color is described as it relates to optical phenomena of color and continues on through colorants and materials used to modulate color and also to human vision of color. The measurement of color is provided as is colorimetry, color spaces, color difference metrics, color appearance models, color order systems and cognitive color. Other topics discussed include industrial color, color imaging, capturing color, displaying color and printing color. Descriptions of color encodings, color management, processing color and applications relating to color synthesis for computer graphics are included in this work. The Encyclo...

  4. Investigating the Force Production of Functionally-Graded Flexible Wings in Flapping Wing Flight

    Science.gov (United States)

    Mudbhari, Durlav; Erdogan, Malcolm; He, Kai; Bateman, Daniel; Lipkis, Rory; Moored, Keith

    2015-11-01

    Birds, insects and bats oscillate their wings to propel themselves over long distances and to maneuver with unprecedented agility. A key element to achieve their impressive aerodynamic performance is the flexibility of their wings. Numerous studies have shown that homogeneously flexible wings can enhance force production, propulsive efficiency and lift efficiency. Yet, animal wings are not homogenously flexible, but instead have varying material properties. The aim of this study is to characterize the force production and energetics of functionally-graded flexible wings. A partially-flexible wing composed of a rigid section and a flexible section is used as a first-order model of functionally-graded materials. The flexion occurs in the spanwise direction and it is affected by the spanwise flexion ratio, that is, the ratio of the length of the rigid section compared to the total span length. By varying the flexion ratio as well as the material properties of the flexible section, the study aims to examine the force production and energetics of flapping flight with functionally-graded flexible wings. Supported by the Office of Naval Research under Program Director Dr. Bob Brizzolara, MURI grant number N00014-14-1-0533.

  5. Aeroelastic Analysis of Modern Complex Wings

    Science.gov (United States)

    Kapania, Rakesh K.; Bhardwaj, Manoj K.; Reichenbach, Eric; Guruswamy, Guru P.

    1996-01-01

    A process is presented by which aeroelastic analysis is performed by using an advanced computational fluid dynamics (CFD) code coupled with an advanced computational structural dynamics (CSD) code. The process is demonstrated on an F/A-18 Stabilator using NASTD (an in-house McDonnell Douglas Aerospace East CFD code) coupled with NASTRAN. The process is also demonstrated on an aeroelastic research wing (ARW-2) using ENSAERO (an in-house NASA Ames Research Center CFD code) coupled with a finite element wing-box structures code. Good results have been obtained for the F/A-18 Stabilator while results for the ARW-2 supercritical wing are still being obtained.

  6. Active Twist Control for a Compliant Wing Structure, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Blended wing body (BWB) aircraft provide an aerodynamically superior solution over traditional tube-and-wing designs for a number of mission profiles. These...

  7. Fixed-Wing Micro Air Vehicles with Hovering Capabilities

    National Research Council Canada - National Science Library

    Bataille, Boris; Poinsot, Damien; Thipyopas, Chinnapat; Moschetta, Jean-Marc

    2007-01-01

    Fixed-wing micro air vehicles (MAV) are very attractive for outdoor surveillance missions since they generally offer better payload and endurance capabilities than rotorcraft or flapping-wing vehicles of equal size...

  8. Measurement of Color Texture

    NARCIS (Netherlands)

    Hoang, M.A.; Geusebroek, J.M.; Deprettere, E.F.; Belloum, A.; Heijnsdijk, J.W.J.; van der Stappen, F.

    2002-01-01

    In computer vision, measurement of image properties such as color or texture is essential. However, existing methods for measuring color and texture in combination are not well-defined neither from a measurement theoretical basis nor from a physical point of view. We propose a solid framework for

  9. Quorum Colorings of Graphs

    NARCIS (Netherlands)

    S.M. Heditniemi (Sandra); R.C. Laskar (R.C.); H.M. Mulder (Martyn)

    2012-01-01

    textabstractLet $G = (V,E)$ be a graph. A partition $\\pi = \\{V_1, V_2, \\ldots, V_k \\}$ of the vertices $V$ of $G$ into $k$ {\\it color classes} $V_i$, with $1 \\leq i \\leq k$, is called a {\\it quorum coloring} if for every vertex $v \\in V$, at least half of the vertices in the closed neighborhood

  10. Colored Contact Lens Dangers

    Medline Plus

    Full Text Available ... Ophthalmologist Patient Stories Español Eye Health / News Halloween Hazard: The Hidden Dangers of Buying Decorative Contact Lenses ... One Use Facts About Colored Contacts and Halloween Safety Colored Contact Lens Facts Over-the-Counter Costume ...

  11. Colored Contact Lens Dangers

    Medline Plus

    Full Text Available ... Eye Health A-Z Symptoms Glasses & Contacts Tips & Prevention News Ask an Ophthalmologist Patient Stories Español Eye ... colored contact lenses , from the U.S. Food and Drug Administration (FDA). Are the colored lenses you are ...

  12. Colored Contact Lens Dangers

    Medline Plus

    Full Text Available ... an Ophthalmologist Patient Stories Español Eye Health / News Halloween Hazard: The Hidden Dangers of Buying Decorative Contact ... After One Use Facts About Colored Contacts and Halloween Safety Colored Contact Lens Facts Over-the-Counter ...

  13. On color transparency

    International Nuclear Information System (INIS)

    Jennings, B.K.; Miller, G.A.

    1989-10-01

    A quantum mechanical treatment of high momentum transfer nuclear processes is presented. Color transparency, the suppression of initial and final state interaction effects, is shown to arise from using the closure approximation. New conditions for the appearance of color transparency are derived

  14. Millennial Teachers of Color

    Science.gov (United States)

    Dilworth, Mary E., Ed.

    2018-01-01

    "Millennial Teachers of Color" explores the opportunities and challenges for creating and sustaining a healthy teaching force in the United States. Millennials are the largest generational cohort in American history, with approximately ninety million members and, of these, roughly 43 percent are people of color. This book, edited by…

  15. Nonlinear Dynamics of Wind Turbine Wings

    DEFF Research Database (Denmark)

    Larsen, Jesper Winther

    Wind turbines with a nominal effect of 5MW with a rotor diameter of up to 126m are produced today. With the increasing size wind turbines also become more and more optimized with respect to structural dimensions and material usage, without increasing the stiffness proportionally. Consequently......, large wind turbines become increasingly flexible and dynamically sensitive. This project focuses on the structural analysis of highly flexible wind turbine wings, and the aerodynamic loading of wind turbine wings under large changes in flow field due to elastic deformations and changing wind conditions....

  16. Stability and transition on swept wings

    Science.gov (United States)

    Stuckert, Greg; Herbert, Thorwald; Esfahanian, Vahid

    1993-01-01

    This paper describes the extension and application of the Parabolized Stability Equations (PSE) to the stability and transition of the supersonic three-dimensional laminar boundary layer on a swept wing. The problem formulation uses a general coordinate transformation for arbitrary curvilinear body-fitted computational grids. Some testing using these coordinates is briefly described to help validate the software used for the investigation. The disturbance amplitude ratios as a function of chord position for supersonic (Mach 1.5) boundary layers on untapered, untwisted wings of different sweep angles are then presented and compared with those obtained from local parallel analyses.

  17. On dominator colorings in graphs

    Indian Academy of Sciences (India)

    A dominator coloring of a graph is a proper coloring of in which every vertex dominates every vertex of at least one color class. The minimum number of colors required for a dominator coloring of is called the dominator chromatic number of and is denoted by d ( G ) . In this paper we present several results on ...

  18. Color quarks and octonions

    International Nuclear Information System (INIS)

    Guersey, F.

    1974-01-01

    A mathematical framework based on octonions is developed for the description of the color quark scheme in which quarks are unobservable, the color SU(3) is exact, and only color singlets correspond to observable hadrons. The fictitious Hilbert space in which quarks operate is taken to be a space of vectors with octonion components. This space admits as a gauge group an exact SU(3) identified with the color SU/sub C/(3). Because of the nonassociativity of the underlying algebra, nonsinglet representations of SU/sub C/(3) are unobservable, while the subspace of color singlets satisfies associativity along with conditions for observability. Octonion quark fields satisfy the commutation relations of parafermions of order 3, leading to the correct SU(6) multiplets for hadrons. (U.S.)

  19. Damage Considerations of a Flexible Micro Air Vehicle Wing Using 3-D Laser Vibrometry

    National Research Council Canada - National Science Library

    Mendoza, Jr, Leo L

    2007-01-01

    .... The flexible micro air vehicle wing studied was based on a University of Florida micro air vehicle wing design and was examined using measurements from the Polytec 400-3D Scanning Vibrometer. Comparisons of the wing?s natural frequencies and displacements were made between the wing?s undamaged and damaged states.

  20. Integrated multi-disciplinary design of a sailplane wing

    OpenAIRE

    Strauch, Gregory J.

    1985-01-01

    The objective of this research is to investigate the techniques and payoffs of integrated aircraft design. Lifting line theory and beam theory are used for the analysis of the aerodynamics and the structures of a composite sailplane wing. The wing is described by 33 - 34 design variables which involve the planform geometry, the twist distribution, and thicknesses of the spar caps, spar webs, and the skin at various stations along the wing. The wing design must satisfy 30 â ...

  1. Speed-dependent modulation of wing muscle recruitment intensity and kinematics in two bat species.

    Science.gov (United States)

    Konow, Nicolai; Cheney, Jorn A; Roberts, Thomas J; Iriarte-Díaz, Jose; Breuer, Kenneth S; Waldman, J Rhea S; Swartz, Sharon M

    2017-05-15

    Animals respond to changes in power requirements during locomotion by modulating the intensity of recruitment of their propulsive musculature, but many questions concerning how muscle recruitment varies with speed across modes of locomotion remain unanswered. We measured normalized average burst EMG (aEMG) for pectoralis major and biceps brachii at different flight speeds in two relatively distantly related bat species: the aerial insectivore Eptesicus fuscus , and the primarily fruit-eating Carollia perspicillata These ecologically distinct species employ different flight behaviors but possess similar wing aspect ratio, wing loading and body mass. Because propulsive requirements usually correlate with body size, and aEMG likely reflects force, we hypothesized that these species would deploy similar speed-dependent aEMG modulation. Instead, we found that aEMG was speed independent in E. fuscus and modulated in a U-shaped or linearly increasing relationship with speed in C. perspicillata This interspecific difference may be related to differences in muscle fiber type composition and/or overall patterns of recruitment of the large ensemble of muscles that participate in actuating the highly articulated bat wing. We also found interspecific differences in the speed dependence of 3D wing kinematics: E. fuscus modulates wing flexion during upstroke significantly more than C. perspicillata Overall, we observed two different strategies to increase flight speed: C. perspicillata tends to modulate aEMG, and E. fuscus tends to modulate wing kinematics. These strategies may reflect different requirements for avoiding negative lift and overcoming drag during slow and fast flight, respectively, a subject we suggest merits further study. © 2017. Published by The Company of Biologists Ltd.

  2. Wind-tunnel investigation of aerodynamic efficiency of three planar elliptical wings with curvature of quarter-chord line

    Science.gov (United States)

    Mineck, Raymond E.; Vijgen, Paul M. H. W.

    1993-01-01

    Three planar, untwisted wings with the same elliptical chord distribution but with different curvatures of the quarter-chord line were tested in the Langley 8-Foot Transonic Pressure Tunnel (8-ft TPT) and the Langley 7- by 10-Foot High-Speed Tunnel (7 x 10 HST). A fourth wing with a rectangular planform and the same projected area and span was also tested. Force and moment measurements from the 8-ft TPT tests are presented for Mach numbers from 0.3 to 0.5 and angles of attack from -4 degrees to 7 degrees. Sketches of the oil-flow patterns on the upper surfaces of the wings and some force and moment measurements from the 7 x 10 HST tests are presented at a Mach number of 0.5. Increasing the curvature of the quarter-chord line makes the angle of zero lift more negative but has little effect on the drag coefficient at zero lift. The changes in lift-curve slope and in the Oswald efficiency factor with the change in curvature of the quarter-chord line (wingtip location) indicate that the elliptical wing with the unswept quarter-chord line has the lowest lifting efficiency and the elliptical wing with the unswept trailing edge has the highest lifting efficiency; the crescent-shaped planform wing has an efficiency in between.

  3. Color evaluation of computer-generated color rainbow holography

    International Nuclear Information System (INIS)

    Shi, Yile; Wang, Hui; Wu, Qiong

    2013-01-01

    A color evaluation approach for computer-generated color rainbow holography (CGCRH) is presented. Firstly, the relationship between color quantities of a computer display and a color computer-generated holography (CCGH) colorimetric system is discussed based on color matching theory. An isochromatic transfer relationship of color quantity and amplitude of object light field is proposed. Secondly, the color reproduction mechanism and factors leading to the color difference between the color object and the holographic image that is reconstructed by CGCRH are analyzed in detail. A quantitative color calculation method for the holographic image reconstructed by CGCRH is given. Finally, general color samples are selected as numerical calculation test targets and the color differences between holographic images and test targets are calculated based on our proposed method. (paper)

  4. Color Orchestra: Ordering Color Palettes for Interpolation and Prediction

    OpenAIRE

    Phan, Huy Q.; Fu, Hongbo; Chan, Antoni B.

    2017-01-01

    Color theme or color palette can deeply influence the quality and the feeling of a photograph or a graphical design. Although color palettes may come from different sources such as online crowd-sourcing, photographs and graphical designs, in this paper, we consider color palettes extracted from fine art collections, which we believe to be an abundant source of stylistic and unique color themes. We aim to capture color styles embedded in these collections by means of statistical models and to ...

  5. Use of wing morphometry for the discrimination of some Cerceris ...

    African Journals Online (AJOL)

    use

    2011-12-14

    Dec 14, 2011 ... Figure 12. Thin spline plate graphics for the species belonging to the genus Cerceris. Figure 13. Fore wing landmarks of the significant wing characteristics in the honeybee Apis mellifera. Linnaeus. stated as the traditional wing morphometry that enables the practical discrimination of the honeybee (Apis sp ...

  6. How swifts control their glide performance with morphing wings

    NARCIS (Netherlands)

    Lentink, D.; Muller, U. K.; Stamhuis, E. J.; de Kat, R.; van Gestel, W.; Veldhuis, L. L. M.; Henningsson, P.; Hedenstrom, A.; Videler, J. J.

    2007-01-01

    Gliding birds continually change the shape and size of their wings(1-6), presumably to exploit the profound effect of wing morphology on aerodynamic performance(7-9). That birds should adjust wing sweep to suit glide speed has been predicted qualitatively by analytical glide models(2,10), which

  7. Study of design parameters of flapping-wings

    NARCIS (Netherlands)

    Wang, Q.; Goosen, J.F.L.; Van Keulen, F.

    2014-01-01

    As one of the most important components of a flapping-wing micro air vehicle (FWMAV), the design of an energy-efficient flapping-wing has been a research interest recently. Research on insect flight from different perspectives has been carried out, mainly with regard to wing morphology, flapping

  8. Low Reynolds Number Wing Transients in Rotation and Translation

    Science.gov (United States)

    Jones, Anya; Schlueter, Kristy

    2012-11-01

    The unsteady aerodynamic forces and flow fields generated by a wing undergoing transient motions in both rotation and translation were investigated. An aspect ratio 2 flat plate wing at a 45 deg angle of attack was driven over 84 deg of rotation (3 chord-lengths of travel at 3/4 span) and 3 and 10 chord-lengths of translation in quiescent water at Reynolds numbers between 2,500 and 15,000. Flow visualization on the rotating wing revealed a leading edge vortex that lifted off of the wing surface, but remained in the vicinity of the wing for the duration of the wing stroke. A second spanwise vortex with strong axial flow was also observed. As the tip vortex grew, the leading edge vortex joined the tip vortex in a loop-like structure over the aft half of the wing. Near the leading edge, spanwise flow in the second vortex became entrained in the tip vortex near the corner of the wing. Unsteady force measurements revealed that lift coefficient increased through the constant-velocity portion of the wing stroke. Forces were compared for variations in wing acceleration and Reynolds number for both rotational and translational motions. The effect of tank blockage was investigated by repeating the experiments on multiple wings, varying the distance between the wing tip and tank wall. U.S. Air Force Research Laboratory, Summer Faculty Fellowship Program.

  9. Spatially resolved chemical analysis of cicada wings using laser-ablation electrospray ionization (LAESI) imaging mass spectrometry (IMS).

    Science.gov (United States)

    Román, Jessica K; Walsh, Callee M; Oh, Junho; Dana, Catherine E; Hong, Sungmin; Jo, Kyoo D; Alleyne, Marianne; Miljkovic, Nenad; Cropek, Donald M

    2018-03-01

    Laser-ablation electrospray ionization (LAESI) imaging mass spectrometry (IMS) is an emerging bioanalytical tool for direct imaging and analysis of biological tissues. Performing ionization in an ambient environment, this technique requires little sample preparation and no additional matrix, and can be performed on natural, uneven surfaces. When combined with optical microscopy, the investigation of biological samples by LAESI allows for spatially resolved compositional analysis. We demonstrate here the applicability of LAESI-IMS for the chemical analysis of thin, desiccated biological samples, specifically Neotibicen pruinosus cicada wings. Positive-ion LAESI-IMS accurate ion-map data was acquired from several wing cells and superimposed onto optical images allowing for compositional comparisons across areas of the wing. Various putative chemical identifications were made indicating the presence of hydrocarbons, lipids/esters, amines/amides, and sulfonated/phosphorylated compounds. With the spatial resolution capability, surprising chemical distribution patterns were observed across the cicada wing, which may assist in correlating trends in surface properties with chemical distribution. Observed ions were either (1) equally dispersed across the wing, (2) more concentrated closer to the body of the insect (proximal end), or (3) more concentrated toward the tip of the wing (distal end). These findings demonstrate LAESI-IMS as a tool for the acquisition of spatially resolved chemical information from fragile, dried insect wings. This LAESI-IMS technique has important implications for the study of functional biomaterials, where understanding the correlation between chemical composition, physical structure, and biological function is critical. Graphical abstract Positive-ion laser-ablation electrospray ionization mass spectrometry coupled with optical imaging provides a powerful tool for the spatially resolved chemical analysis of cicada wings.

  10. Color associations for days and letters across different languages

    Directory of Open Access Journals (Sweden)

    Romke eRouw

    2014-05-01

    Full Text Available While colors are commonplace in everyday metaphors, relatively little is known about implicit color associations to linguistic or semantic concepts in a general population. In this study, we test color associations for ordered linguistic concepts (letters and days. The culture and language specificity of these effects was examined in a large group (457 of Dutch-speaking participants, 92 English-speaking participants, and 49 Hindi-speaking participants. Non-random distributions of color choices were revealed; consistencies were found across the three language groups in color preferences for both days and letters. Interestingly, while the Hindi-speaking participants were presented with letter stimuli matched on phonology, their pattern of letter-to-color preferences still showed similarities with Dutch- and English-speaking participants. Furthermore, we found that that the color preferences corresponded between participants indicating to have conscious color experiences with letters or days (putative synesthetes and participants who do not (non-synesthetes. We also explored possible mechanisms underlying the color preferences. There were a few specific associations, including red for A, red for Monday, and white for Sunday. We also explored more general mechanisms, such as overall color preferences shown by Simner et al (2005. While certainly not all variation can be explained or predicted, the results show that regularities are present in color-to-letter or color-to-day preferences in both putative synesthetes and non-synesthetes across languages. Both letter-to-color and day-to-color preferences were influenced by multiple factors. The findings support a notion of abstract concepts (such as days and letters that are not represented in isolation, but are connected to perceptual representational systems. Interestingly, at least some of these connections to color representations are shared across different language/cultural groups.

  11. Air Base Wing and Air Mobility Wing Consolidating on AMC-LED Joint Bases: A Delphi Study

    Science.gov (United States)

    2014-06-13

    AIR BASE WING AND AIR MOBILITY WING CONSOLIDATION ON AMC-LED JOINT BASES: A DELPHI STUDY GRADUATE RESEARCH PAPER Mason E. MacGarvey... DELPHI STUDY GRADUATE RESEARCH PAPER Presented to the Faculty Graduate School of Engineering Management Air Force Institute of Technology...iv AIR BASE WING AND AIR MOBILITY WING CONSOLIDATION ON AMC-LED JOINT BASES: A DELPHI STUDY Mason E. MacGarvey, BS, MBA

  12. Stool Color: When to Worry

    Science.gov (United States)

    Stool color: When to worry Yesterday, my stool color was bright green. Should I be concerned? Answers from Michael ... M.D. Stool comes in a range of colors. All shades of brown and even green are ...

  13. Neural representation of form-contingent color filling-in in the early visual cortex.

    Science.gov (United States)

    Hong, Sang Wook; Tong, Frank

    2017-11-01

    Perceptual filling-in exemplifies the constructive nature of visual processing. Color, a prominent surface property of visual objects, can appear to spread to neighboring areas that lack any color. We investigated cortical responses to a color filling-in illusion that effectively dissociates perceived color from the retinal input (van Lier, Vergeer, & Anstis, 2009). Observers adapted to a star-shaped stimulus with alternating red- and cyan-colored points to elicit a complementary afterimage. By presenting an achromatic outline that enclosed one of the two afterimage colors, perceptual filling-in of that color was induced in the unadapted central region. Visual cortical activity was monitored with fMRI, and analyzed using multivariate pattern analysis. Activity patterns in early visual areas (V1-V4) reliably distinguished between the two color-induced filled-in conditions, but only higher extrastriate visual areas showed the predicted correspondence with color perception. Activity patterns allowed for reliable generalization between filled-in colors and physical presentations of perceptually matched colors in areas V3 and V4, but not in earlier visual areas. These findings suggest that the perception of filled-in surface color likely requires more extensive processing by extrastriate visual areas, in order for the neural representation of surface color to become aligned with perceptually matched real colors.

  14. Morphing Wing: Experimental Boundary Layer Transition Determination and Wing Vibrations Measurements and Analysis =

    Science.gov (United States)

    Tondji Chendjou, Yvan Wilfried

    This Master's thesis is written within the framework of the multidisciplinary international research project CRIAQ MDO-505. This global project consists of the design, manufacture and testing of a morphing wing box capable of changing the shape of the flexible upper skin of a wing using an actuator system installed inside the wing. This changing of the shape generates a delay in the occurrence of the laminar to turbulent transition area, which results in an improvement of the aerodynamic performances of the morphed wing. This thesis is focused on the technologies used to gather the pressure data during the wind tunnel tests, as well as on the post processing methodologies used to characterize the wing airflow. The vibration measurements of the wing and their real-time graphical representation are also presented. The vibration data acquisition system is detailed, and the vibration data analysis confirms the predictions of the flutter analysis performed on the wing prior to wind tunnel testing at the IAR-NRC. The pressure data was collected using 32 highly-sensitive piezoelectric sensors for sensing the pressure fluctuations up to 10 KHz. These sensors were installed along two wing chords, and were further connected to a National Instrument PXI real-time acquisition system. The acquired pressure data was high-pass filtered, analyzed and visualized using Fast Fourier Transform (FFT) and Standard Deviation (SD) approaches to quantify the pressure fluctuations in the wing airflow, as these allow the detection of the laminar to turbulent transition area. Around 30% of the cases tested in the IAR-NRC wind tunnel were optimized for drag reduction by the morphing wing procedure. The obtained pressure measurements results were compared with results obtained by infrared thermography visualization, and were used to validate the numerical simulations. Two analog accelerometers able to sense dynamic accelerations up to +/-16g were installed in both the wing and the aileron boxes

  15. Machine Learning for Flapping Wing Flight Control

    NARCIS (Netherlands)

    Goedhart, Menno; van Kampen, E.; Armanini, S.F.; de Visser, C.C.; Chu, Q.

    2018-01-01

    Flight control of Flapping Wing Micro Air Vehicles is challenging, because of their complex dynamics and variability due to manufacturing inconsistencies. Machine Learning algorithms can be used to tackle these challenges. A Policy Gradient algorithm is used to tune the gains of a

  16. Migration on Wings Aerodynamics and Energetics

    CERN Document Server

    Kantha, Lakshmi

    2012-01-01

    This book is an effort to explore the technical aspects associated with bird flight and migration on wings. After a short introduction on the birds migration, the book reviews the aerodynamics and Energetics of Flight and presents the calculation of the Migration Range. In addition, the authors explains aerodynamics of the formation flight and finally introduces great flight diagrams.

  17. Oblique-Flying-Wing Supersonic Transport Airplane

    Science.gov (United States)

    Van Der Velden, Alexander J. M.

    1992-01-01

    Oblique-flying-wing supersonic airplane proposed as possible alternative to B747B (or equivalent). Tranports passengers and cargo as fast as twice speed of sound at same cost as current subsonic transports. Flies at same holding speeds as present supersonic transports but requires only half takeoff distance.

  18. Chemical evaluation of winged beans ( Psophocarpus ...

    African Journals Online (AJOL)

    Chemical evaluation of winged beans ( Psophocarpus Tetragonolobus ), Pitanga cherries ( Eugenia uniflora) and orchid fruit ( Orchid fruit myristic a) ... The acid value ranged between 0.71 and 2.82 mg/KOH/g while iodine value ranged between 91.15 and 144.57. The refractive index ranged between 1.465 and 1.474 in all ...

  19. ``Schooling'' of wing pairs in flapping flight

    Science.gov (United States)

    Ramananarivo, Sophie; Zhang, Jun; Ristroph, Leif; AML, Courant Collaboration; Physics NYU Collaboration

    2015-11-01

    The experimental setup implements two independent flapping wings swimming in tandem. Both are driven with the same prescribed vertical heaving motion, but the horizontal motion is free, which means that the swimmers can take up any relative position and forward speed. Experiments show however clearly coordinated motions, where the pair of wings `crystallize' into specific stable arrangements. The follower wing locks into the path of the leader, adopting its speed, and with a separation distance that takes on one of several discrete values. By systematically varying the kinematics and wing size, we show that the set of stable spacings is dictated by the wavelength of the periodic wake structure. The forces maintaining the pair cohesion are characterized by applying an external force to the follower to perturb it away from the `stable wells'. These results show that hydrodynamics alone is sufficient to induce cohesive and coordinated collective locomotion through a fluid, and we discuss the hypothesis that fish schools and bird flocks also represent stable modes of motion.

  20. Wind Tunnel Test of a Risk-Reduction Wing/Fuselage Model to Examine Juncture-Flow Phenomena

    Science.gov (United States)

    Kegerise, Michael A.; Neuhart, Dan H.

    2016-01-01

    A wing/fuselage wind-tunnel model was tested in the Langley 14- by 22-foot Subsonic Wind Tunnel in preparation for a highly-instrumented Juncture Flow Experiment to be conducted in the same facility. This test, which was sponsored by the NASA Transformational Tool and Technologies Project, is part of a comprehensive set of experimental and computational research activities to develop revolutionary, physics-based aeronautics analysis and design capability. The objectives of this particular test were to examine the surface and off-body flow on a generic wing/body combination to: 1) choose a final wing for a future, highly instrumented model, 2) use the results to facilitate unsteady pressure sensor placement on the model, 3) determine the area to be surveyed with an embedded laser-doppler velocimetry (LDV) system, 4) investigate the primary juncture corner- flow separation region using particle image velocimetry (PIV) to see if the particle seeding is adequately entrained and to examine the structure in the separated region, and 5) to determine the similarity of observed flow features with those predicted by computational fluid dynamics (CFD). This report documents the results of the above experiment that specifically address the first three goals. Multiple wing configurations were tested at a chord Reynolds number of 2.4 million. Flow patterns on the surface of the wings and in the region of the wing/fuselage juncture were examined using oil- flow visualization and infrared thermography. A limited number of unsteady pressure sensors on the fuselage around the wing leading and trailing edges were used to identify any dynamic effects of the horseshoe vortex on the flow field. The area of separated flow in the wing/fuselage juncture near the wing trailing edge was observed for all wing configurations at various angles of attack. All of the test objectives were met. The staff of the 14- by 22-foot Subsonic Wind Tunnel provided outstanding support and delivered

  1. Aerodynamic comparison of a butterfly-like flapping wing-body model and a revolving-wing model

    Science.gov (United States)

    Suzuki, Kosuke; Yoshino, Masato

    2017-06-01

    The aerodynamic performance of flapping- and revolving-wing models is investigated by numerical simulations based on an immersed boundary-lattice Boltzmann method. As wing models, we use (i) a butterfly-like model with a body and flapping-rectangular wings and (ii) a revolving-wing model with the same wings as the flapping case. Firstly, we calculate aerodynamic performance factors such as the lift force, the power, and the power loading of the two models for Reynolds numbers in the range of 50-1000. For the flapping-wing model, the power loading is maximal for the maximum angle of attack of 90°, a flapping amplitude of roughly 45°, and a phase shift between the flapping angle and the angle of attack of roughly 90°. For the revolving-wing model, the power loading peaks for an angle of attack of roughly 45°. In addition, we examine the ground effect on the aerodynamic performance of the revolving-wing model. Secondly, we compare the aerodynamic performance of the flapping- and revolving-wing models at their respective maximal power loadings. It is found that the revolving-wing model is more efficient than the flapping-wing model both when the body of the latter is fixed and where it can move freely. Finally, we discuss the relative agilities of the flapping- and revolving-wing models.

  2. Paleozoic Nymphal Wing Pads Support Dual Model of Insect Wing Origins.

    Science.gov (United States)

    Prokop, Jakub; Pecharová, Martina; Nel, André; Hörnschemeyer, Thomas; Krzemińska, Ewa; Krzemiński, Wiesław; Engel, Michael S

    2017-01-23

    The appearance of wings in insects, early in their evolution [1], has been one of the more critical innovations contributing to their extraordinary diversity. Despite the conspicuousness and importance of wings, the origin of these structures has been difficult to resolve and represented one of the "abominable mysteries" in evolutionary biology [2]. More than a century of debate has boiled the matter down to two competing alternatives-one of wings representing an extension of the thoracic notum, the other stating that they are appendicular derivations from the lateral body wall. Recently, a dual model has been supported by genomic and developmental data [3-6], representing an amalgamation of elements from both the notal and pleural hypotheses. Here, we reveal crucial information from the wing pad joints of Carboniferous palaeodictyopteran insect nymphs using classical and high-tech techniques. These nymphs had three pairs of wing pads that were medially articulated to the thorax but also broadly contiguous with the notum anteriorly and posteriorly (details unobservable in modern insects), supporting their overall origin from the thoracic notum as well as the expected medial, pleural series of axillary sclerites. Our study provides support for the formation of the insect wing from the thoracic notum as well as the already known pleural elements of the arthropodan leg. These results support the unique, dual model for insect wing origins and the convergent reduction of notal fusion in more derived clades, presumably due to wing rotation during development, and they help to bring resolution to this long-standing debate. Copyright © 2017 Elsevier Ltd. All rights reserved.

  3. Variability of the Structural Coloration in Two Butterfly Species with Different Prezygotic Mating Strategies.

    Science.gov (United States)

    Piszter, Gábor; Kertész, Krisztián; Bálint, Zsolt; Biró, László Péter

    2016-01-01

    Structural coloration variability was investigated in two Blue butterfly species that are common in Hungary. The males of Polyommatus icarus (Common Blue) and Plebejus argus (Silver-studded Blue) use their blue wing coloration for conspecific recognition. Despite living in the same type of habitat, these two species display differences in prezygotic mating strategy: the males of P. icarus are patrolling, while P. argus males have sedentary behavior. Therefore, the species-specific photonic nanoarchitecture, which is the source of the structural coloration, may have been subjected to different evolutionary effects. Despite the increasing interest in photonic nanoarchitectures of biological origin, there is a lack of studies focused on the biological variability of structural coloration that examine a statistically relevant number of individuals from the same species. To investigate possible structural color variation within the same species in populations separated by large geographical distances, climatic differences, or applied experimental conditions, one has to be able to compare these variations to the normal biological variability within a single population. The structural coloration of the four wings of 25 male individuals (100 samples for each species) was measured and compared using different light-collecting setups: perpendicular and with an integrating sphere. Significant differences were found in the near UV wavelength region that are perceptible by these polyommatine butterflies but are invisible to human observers. The differences are attributed to the differences in the photonic nanoarchitecture in the scales of these butterflies. Differences in the intensity of structural coloration were also observed and were tentatively attributed to the different prezygotic mating strategies of these insects. Despite the optical complexity of the scale covered butterfly wings, for sufficiently large sample batches, the averaged normal incidence measurements and

  4. Variability of the Structural Coloration in Two Butterfly Species with Different Prezygotic Mating Strategies.

    Directory of Open Access Journals (Sweden)

    Gábor Piszter

    Full Text Available Structural coloration variability was investigated in two Blue butterfly species that are common in Hungary. The males of Polyommatus icarus (Common Blue and Plebejus argus (Silver-studded Blue use their blue wing coloration for conspecific recognition. Despite living in the same type of habitat, these two species display differences in prezygotic mating strategy: the males of P. icarus are patrolling, while P. argus males have sedentary behavior. Therefore, the species-specific photonic nanoarchitecture, which is the source of the structural coloration, may have been subjected to different evolutionary effects. Despite the increasing interest in photonic nanoarchitectures of biological origin, there is a lack of studies focused on the biological variability of structural coloration that examine a statistically relevant number of individuals from the same species. To investigate possible structural color variation within the same species in populations separated by large geographical distances, climatic differences, or applied experimental conditions, one has to be able to compare these variations to the normal biological variability within a single population. The structural coloration of the four wings of 25 male individuals (100 samples for each species was measured and compared using different light-collecting setups: perpendicular and with an integrating sphere. Significant differences were found in the near UV wavelength region that are perceptible by these polyommatine butterflies but are invisible to human observers. The differences are attributed to the differences in the photonic nanoarchitecture in the scales of these butterflies. Differences in the intensity of structural coloration were also observed and were tentatively attributed to the different prezygotic mating strategies of these insects. Despite the optical complexity of the scale covered butterfly wings, for sufficiently large sample batches, the averaged normal incidence

  5. Variability of the Structural Coloration in Two Butterfly Species with Different Prezygotic Mating Strategies

    Science.gov (United States)

    Kertész, Krisztián; Bálint, Zsolt; Biró, László Péter

    2016-01-01

    Structural coloration variability was investigated in two Blue butterfly species that are common in Hungary. The males of Polyommatus icarus (Common Blue) and Plebejus argus (Silver-studded Blue) use their blue wing coloration for conspecific recognition. Despite living in the same type of habitat, these two species display differences in prezygotic mating strategy: the males of P. icarus are patrolling, while P. argus males have sedentary behavior. Therefore, the species-specific photonic nanoarchitecture, which is the source of the structural coloration, may have been subjected to different evolutionary effects. Despite the increasing interest in photonic nanoarchitectures of biological origin, there is a lack of studies focused on the biological variability of structural coloration that examine a statistically relevant number of individuals from the same species. To investigate possible structural color variation within the same species in populations separated by large geographical distances, climatic differences, or applied experimental conditions, one has to be able to compare these variations to the normal biological variability within a single population. The structural coloration of the four wings of 25 male individuals (100 samples for each species) was measured and compared using different light-collecting setups: perpendicular and with an integrating sphere. Significant differences were found in the near UV wavelength region that are perceptible by these polyommatine butterflies but are invisible to human observers. The differences are attributed to the differences in the photonic nanoarchitecture in the scales of these butterflies. Differences in the intensity of structural coloration were also observed and were tentatively attributed to the different prezygotic mating strategies of these insects. Despite the optical complexity of the scale covered butterfly wings, for sufficiently large sample batches, the averaged normal incidence measurements and

  6. Biological origins of color categorization

    OpenAIRE

    Skelton, Alice E.; Catchpole, Gemma; Abbott, Joshua T.; Bosten, Jenny M.; Franklin, Anna

    2017-01-01

    The biological basis of the commonality in color lexicons across languages has been hotly debated for decades. Prior evidence that infants categorize color could provide support for the hypothesis that color categorization systems are not purely constructed by communication and culture. Here, we investigate the relationship between infants’ categorization of color and the commonality across color lexicons, and the potential biological origin of infant color categories. We systematically mappe...

  7. Combinatorial color arrays based on optical micro-resonators in monolithic architecture.

    Science.gov (United States)

    Lee, In-Ho; Lee, Sin-Hyung; Keum, Chang-Min; Kim, Se-Um; Lee, Sin-Doo

    2014-06-16

    We demonstrate two types of combinatorial color arrays based on the Fabry-Perot (FP) micro-resonators in monolithic architecture. Optical micro-resonators corresponding to color elements are constructed using a soluble dielectric material between two transreflective layers by transfer-printing in either a pattern-by-pattern or a pattern-on-pattern fashion. The color palette depends primarily on the thickness and the refractive index of a dielectric material embedded in the micro-resonator. A self-defined lateral gap between two adjacent color elements provides the functionality of light-blocking by the underlying background layer. A prototype of a liquid crystal display incorporated with our combinatorial color array is also demonstrated. This monolithic integration of different FP micro-resonators leads to a versatile platform to build up a new class of color arrays for a variety of visual applications including displays and coloration devices.

  8. Distribution and predictors of wing shape and size variability in three sister species of solitary bees.

    Directory of Open Access Journals (Sweden)

    Simon Dellicour

    Full Text Available Morphological traits can be highly variable over time in a particular geographical area. Different selective pressures shape those traits, which is crucial in evolutionary biology. Among these traits, insect wing morphometry has already been widely used to describe phenotypic variability at the inter-specific level. On the contrary, fewer studies have focused on intra-specific wing morphometric variability. Yet, such investigations are relevant to study potential convergences of variation that could highlight micro-evolutionary processes. The recent sampling and sequencing of three solitary bees of the genus Melitta across their entire species range provides an excellent opportunity to jointly analyse genetic and morphometric variability. In the present study, we first aim to analyse the spatial distribution of the wing shape and centroid size (used as a proxy for body size variability. Secondly, we aim to test different potential predictors of this variability at both the intra- and inter-population levels, which includes genetic variability, but also geographic locations and distances, elevation, annual mean temperature and precipitation. The comparison of spatial distribution of intra-population morphometric diversity does not reveal any convergent pattern between species, thus undermining the assumption of a potential local and selective adaptation at the population level. Regarding intra-specific wing shape differentiation, our results reveal that some tested predictors, such as geographic and genetic distances, are associated with a significant correlation for some species. However, none of these predictors are systematically identified for the three species as an important factor that could explain the intra-specific morphometric variability. As a conclusion, for the three solitary bee species and at the scale of this study, our results clearly tend to discard the assumption of the existence of a common pattern of intra-specific signal

  9. Distribution and predictors of wing shape and size variability in three sister species of solitary bees.

    Science.gov (United States)

    Dellicour, Simon; Gerard, Maxence; Prunier, Jérôme G; Dewulf, Alexandre; Kuhlmann, Michael; Michez, Denis

    2017-01-01

    Morphological traits can be highly variable over time in a particular geographical area. Different selective pressures shape those traits, which is crucial in evolutionary biology. Among these traits, insect wing morphometry has already been widely used to describe phenotypic variability at the inter-specific level. On the contrary, fewer studies have focused on intra-specific wing morphometric variability. Yet, such investigations are relevant to study potential convergences of variation that could highlight micro-evolutionary processes. The recent sampling and sequencing of three solitary bees of the genus Melitta across their entire species range provides an excellent opportunity to jointly analyse genetic and morphometric variability. In the present study, we first aim to analyse the spatial distribution of the wing shape and centroid size (used as a proxy for body size) variability. Secondly, we aim to test different potential predictors of this variability at both the intra- and inter-population levels, which includes genetic variability, but also geographic locations and distances, elevation, annual mean temperature and precipitation. The comparison of spatial distribution of intra-population morphometric diversity does not reveal any convergent pattern between species, thus undermining the assumption of a potential local and selective adaptation at the population level. Regarding intra-specific wing shape differentiation, our results reveal that some tested predictors, such as geographic and genetic distances, are associated with a significant correlation for some species. However, none of these predictors are systematically identified for the three species as an important factor that could explain the intra-specific morphometric variability. As a conclusion, for the three solitary bee species and at the scale of this study, our results clearly tend to discard the assumption of the existence of a common pattern of intra-specific signal/structure within the

  10. Color universal design: analysis of color category dependency on color vision type (3)

    Science.gov (United States)

    Kojima, Natsuki; Ichihara, Yasuyo G.; Ikeda, Tomohiro; Kamachi, Miyuki G.; Ito, Kei

    2012-01-01

    We report on the results of a study investigating the color perception characteristics of people with red-green color confusion. We believe that this is an important step towards achieving Color Universal Design. In Japan, approximately 5% of men and 0.2% of women have red-green confusion. The percentage for men is higher in Europe and the United States; up to 8% in some countries. Red-green confusion involves a perception of colors different from normal color vision. Colors are used as a means of disseminating clear information to people; however, it may be difficult to convey the correct information to people who have red-green confusion. Consequently, colors should be chosen that minimize accidents and that promote more effective communication. In a previous survey, we investigated color categories common to each color vision type, trichromat (C-type color vision), protan (P-type color vision) and deuteran (D-type color vision). In the present study, first, we conducted experiments in order to verify a previous survey of C-type color vision and P-type color vision. Next, we investigated color difference levels within "CIE 1976 L*a*b*" (the CIELAB uniform color space), where neither C-type nor P-type color vision causes accidents under certain conditions (rain maps/contour line levels and graph color legend levels). As a result, we propose a common chromaticity of colors that the two color vision types are able to categorize by means of color names common to C-type color vision. We also offer a proposal to explain perception characteristics of color differences with normal color vision and red-green confusion using the CIELAB uniform color space. This report is a follow-up to SPIE-IS & T / Vol. 7528 7528051-8 and SPIE-IS & T /vol. 7866 78660J-1-8.

  11. A study on forces acting on a flapping wing

    Directory of Open Access Journals (Sweden)

    Cetiner O.

    2013-04-01

    Full Text Available In order to study the forces acting on a flapping wing, an experimental investigation is performed in steady water flow. In this study, a SD7003 airfoil undergoes combined pitching and plunging motion which simulates the forward flight of small birds. The frequency of pitching motion is equal to the frequency of plunging motion and pitch leads the plunge by a phase angle of 90 degrees. The experiments are conducted at Reynolds numbers of 2500 ≤ Re ≤ 13700 and the vortex formation is recorded using the digital particle image velocimetry (DPIV technique. A prediction of thrust force and efficiency is calculated from the average wake deficit of DPIV data, the near-wake vorticity patterns and time dependent velocity vectors are determined to comment on the thrust and drag indication. Direct force measurements are attempted using a Force/Torque sensor which is capable of measuring forces and moments in three axial directions.

  12. Multiple cues for winged morph production in an aphid metacommunity.

    Directory of Open Access Journals (Sweden)

    Mohsen Mehrparvar

    Full Text Available Environmental factors can lead individuals down different developmental pathways giving rise to distinct phenotypes (phenotypic plasticity. The production of winged or unwinged morphs in aphids is an example of two alternative developmental pathways. Dispersal is paramount in aphids that often have a metapopulation structure, where local subpopulations frequently go extinct, such as the specialized aphids on tansy (Tanacetum vulgare. We conducted various experiments to further understand the cues involved in the production of winged dispersal morphs by the two dominant species of the tansy aphid metacommunity, Metopeurum fuscoviride and Macrosiphoniella tanacetaria. We found that the ant-tended M. fuscoviride produced winged individuals predominantly at the beginning of the season while the untended M. tanacetaria produced winged individuals throughout the season. Winged mothers of both species produced winged offspring, although in both species winged offspring were mainly produced by unwinged females. Crowding and the presence of predators, effects already known to influence wing production in other aphid species, increased the percentage of winged offspring in M. tanacetaria, but not in M. fuscoviride. We find there are also other factors (i.e. temporal effects inducing the production of winged offspring for natural aphid populations. Our results show that the responses of each aphid species are due to multiple wing induction cues.

  13. Colored Contact Lens Dangers

    Medline Plus

    Full Text Available ... colored contact lenses to enhance their costumes. From blood-drenched vampire eyes to glow-in-the-dark ... properly fitted may scratch the eye or cause blood vessels to grow into the cornea. Even if ...

  14. Food Coloring and Behavior

    OpenAIRE

    J Gordon Millichap

    1994-01-01

    The association between the ingestion of tartrazine synthetic food coloring and behavioral change in children referred for assessment of hyperactivity was investigated at the Royal Children’s Hospital, University of Melbourne, Australia.

  15. Colored Contact Lens Dangers

    Medline Plus

    Full Text Available ... in a pair of colored contact lenses, Laura Butler of Parkersburg, W.Va., had "extreme pain in ... to wear any kind of contact lens. In Butler's case, the lenses caused an infection and left ...

  16. Colored Contact Lens Dangers

    Medline Plus

    Full Text Available ... Cleveland. "This is far from the truth." Real People, Real Problems with Colored Contact Lenses Julian: Teenager ... About the Academy Jobs at the Academy Financial Relationships with Industry Medical Disclaimer Privacy Policy Terms of ...

  17. Colored Contact Lens Dangers

    Medline Plus

    Full Text Available ... asociados con los lentes de contacto de color Sep. 26, 2013 It started as an impulsive buy ... to its original shape after wearing orthokeratology lenses? Sep 13, 2017 Histoplasmosis Diagnosis Sep 01, 2017 How ...

  18. UBV MEAN ASTEROID COLORS

    Data.gov (United States)

    National Aeronautics and Space Administration — This data set is a compilation of mean U-B and B-V color indices of asteroids, collected from the published literature and from the unpublished Lowell Observatory...

  19. Colored Contact Lens Dangers

    Medline Plus

    Full Text Available ... about the members of the eye-care team . Consumer warning about the improper use of colored contact ... About the Academy Jobs at the Academy Financial Relationships with Industry Medical Disclaimer Privacy Policy Terms of ...

  20. Colors of the Sky.

    Science.gov (United States)

    Bohren, Craig F.; Fraser, Alistair B.

    1985-01-01

    Explains the physical principles which result in various colors of the sky. Topics addressed include: blueness, mystical properties of water vapor, ozone, fluctuation theory of scattering, variation of purity and brightness, and red sunsets and sunrises. (DH)

  1. Colored Contact Lens Dangers

    Medline Plus

    Full Text Available ... Cleveland. "This is far from the truth." Real People, Real Problems with Colored Contact Lenses Julian: Teenager ... the lenses. Never share contact lenses with another person. Get follow up exams with your eye care ...

  2. Colored Contact Lens Dangers

    Medline Plus

    Full Text Available ... popping touch. But colored contact lenses are popular year-round, not just at Halloween. But few know the ... also available in Spanish . Follow The Academy Professionals: Education Guidelines News Multimedia Public & Patients: Contact Us About ...

  3. Facts About Color Blindness

    Science.gov (United States)

    ... Program Hispanic/Latino Program Vision and Aging Program African American Program Training and Jobs Fellowships NEI Summer ... a green chalkboard when yellow chalk is used. Art classes, which require selecting appropriate colors of paint ...

  4. Colored Contact Lens Dangers

    Medline Plus

    Full Text Available ... to the journals may be interrupted during this time. We are working to resolve the issue quickly ... like a suction cup." Halloween is a popular time for people to use colored contact lenses to ...

  5. Colored Contact Lens Dangers

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    Full Text Available ... Purchase the colored contact lenses from an eye product retailer who asks for a prescription. Follow the ... for people with high myopia? Mar 29, 2017 New Technology Helps the Legally Blind Be More Independent ...

  6. Colored Contact Lens Dangers

    Medline Plus

    Full Text Available ... Hidden Dangers of Buying Decorative Contact Lenses Without a Prescription Leer en Español: Peligros asociados con los ... contacto de color Sep. 26, 2013 It started as an impulsive buy from a souvenir shop, but ...

  7. Colored Contact Lens Dangers

    Medline Plus

    Full Text Available ... be purchased over-the-counter or on the Internet," says Thomas Steinemann, MD, professor of ophthalmology at ... are being sold illegally," Dr. Steinemann said. Never buy colored contact lenses from a retailer that does ...

  8. Colored Contact Lens Dangers

    Medline Plus

    Full Text Available ... lens because they can be purchased over-the-counter or on the Internet," says Thomas Steinemann, MD, ... Halloween Safety Colored Contact Lens Facts Over-the-Counter Costume Contacts May Contain Chemicals Harmful to Eyes ...

  9. Colored Contact Lens Dangers

    Medline Plus

    Full Text Available ... like a suction cup." Halloween is a popular time for people to use colored contact lenses to ... wear costume contact lenses for Halloween or any time of year, follow these guidelines: Get an eye ...

  10. Colored Contact Lens Dangers

    Medline Plus

    Full Text Available ... contact lenses , from the U.S. Food and Drug Administration (FDA). Are the colored lenses you are considering ... Follow The Academy Professionals: Education Guidelines News Multimedia Public & Patients: Contact Us About the Academy Jobs at ...

  11. 52-COLOR ASTEROID SURVEY

    Data.gov (United States)

    National Aeronautics and Space Administration — This data set contains 52-color IR data of asteroids, taken using a double circularly variable filter. The short wavelength portion of the CVF covered the octave...

  12. Compressed Subsequence Matching and Packed Tree Coloring

    DEFF Research Database (Denmark)

    Bille, Philip; Cording, Patrick Hagge; Gørtz, Inge Li

    2017-01-01

    We present a new algorithm for subsequence matching in grammar compressed strings. Given a grammar of size n compressing a string of size N and a pattern string of size m over an alphabet of size \\(\\sigma \\), our algorithm uses \\(O(n+\\frac{n\\sigma }{w})\\) space and \\(O(n+\\frac{n\\sigma }{w}+m\\log ...... a new data structure that allows us to efficiently find the next occurrence of a given character after a given position in a compressed string. This data structure in turn is based on a new data structure for the tree color problem, where the node colors are packed in bit strings....

  13. The biomechanical origin of extreme wing allometry in hummingbirds.

    Science.gov (United States)

    Skandalis, Dimitri A; Segre, Paolo S; Bahlman, Joseph W; Groom, Derrick J E; Welch, Kenneth C; Witt, Christopher C; McGuire, Jimmy A; Dudley, Robert; Lentink, David; Altshuler, Douglas L

    2017-10-19

    Flying animals of different masses vary widely in body proportions, but the functional implications of this variation are often unclear. We address this ambiguity by developing an integrative allometric approach, which we apply here to hummingbirds to examine how the physical environment, wing morphology and stroke kinematics have contributed to the evolution of their highly specialised flight. Surprisingly, hummingbirds maintain constant wing velocity despite an order of magnitude variation in body weight; increased weight is supported solely through disproportionate increases in wing area. Conversely, wing velocity increases with body weight within species, compensating for lower relative wing area in larger individuals. By comparing inter- and intraspecific allometries, we find that the extreme wing area allometry of hummingbirds is likely an adaptation to maintain constant burst flight capacity and induced power requirements with increasing weight. Selection for relatively large wings simultaneously maximises aerial performance and minimises flight costs, which are essential elements of humming bird life history.

  14. Color Laser Microscope

    Science.gov (United States)

    Awamura, D.; Ode, T.; Yonezawa, M.

    1987-04-01

    A color laser microscope utilizing a new color laser imaging system has been developed for the visual inspection of semiconductors. The light source, produced by three lasers (Red; He-Ne, Green; Ar, Blue; He-Cd), is deflected horizontally by an AOD (Acoustic Optical Deflector) and vertically by a vibration mirror. The laser beam is focused in a small spot which is scanned over the sample at high speed. The light reflected back from the sample is reformed to contain linear information by returning to the original vibration mirror. The linear light is guided to the CCD image sensor where it is converted into a video signal. Individual CCD image sensors are used for each of the three R, G, or B color image signals. The confocal optical system with its laser light source yields a color TV monitor image with no flaring and a much sharper resolution than that of the conventional optical microscope. The AOD makes possible a high speed laser scan and a NTSC or PAL TV video signal is produced in real time without any video memory. Since the light source is composed of R, G, and B laser beams, color separation superior to that of white light illumination is achieved. Because of the photometric linearity of the image detector, the R, G, and B outputs of the system are most suitably used for hue analysis. The CCD linear image sensors in the optical system produce no geometrical distortion, and good color registration is available principally. The output signal can be used for high accuracy line width measuring. The many features of the color laser microscope make it ideally suited for the visual inspection of semiconductor processing. A number of these systems have already been installed in such a capacity. The Color Laser Microscope can also be a very useful tool for the fields of material engineering and biotechnology.

  15. COLOR- SENSITIZED SOLAR ELEMENTS

    OpenAIRE

    Gish R. A.; Ranabkhat K.; Yatsenko A. N.

    2016-01-01

    Photovoltaic devices are a promising solution to the energy crisis, because they generate electricity directly from sunlight, without producing CO2. While color-sensitized batteries are the most studied element, mainly due to its low cost and high efficiency solar energy conversion into electricity. Until recently, the color-sensitized solar cells performance was less than 1%, however, the use of titanium dioxide as the anode material have greatly raised their efficiency. The advantages of ti...

  16. Gauge color codes

    DEFF Research Database (Denmark)

    Bombin Palomo, Hector

    2015-01-01

    Color codes are topological stabilizer codes with unusual transversality properties. Here I show that their group of transversal gates is optimal and only depends on the spatial dimension, not the local geometry. I also introduce a generalized, subsystem version of color codes. In 3D they allow t...... the transversal implementation of a universal set of gates by gauge fixing, while error-dectecting measurements involve only four or six qubits....

  17. Color in interior spaces

    OpenAIRE

    Demirörs, Müge Bozbeyli

    1992-01-01

    Ankara : The Department of Interior Architecture and Environmental Design and the Institute of Fine Arts of Bilkent University, 1992. Thesis (Master's) -- -Bilkent University, 1992. Includes bibliographical references leaves 95-99. Color can be approached from different perspectives and disciplines such as, biology, theory, technology, and psychology. This thesis discusses color, from the stand point of interior spaces, which to some extent involves most of these discipli...

  18. Association between antennal phenotype, wing polymorphism and sex in the genus Mepraia (Reduviidae: Triatominae).

    Science.gov (United States)

    Moreno, Mariana Laura; Gorla, David; Catalá, Silvia

    2006-05-01

    Mepraia spinolai and Mepraia gajardoi (Hemiptera, Reduviidae) are only found in the arid regions of northern Chile. Mepraia is the only genus of Triatominae with marked wing polymorphism. Females of both species are micropterous, males of M. spinolai may be micropterous, brachypterous or macropterous, while males of M. gajardoi are always brachypterous. Because of this wing polymorphism, Mepraia can be used as a model to analyze morphological adaptations related to the flying activity and evolutionary relationships in the Triatominae. The study presented here analyses the antennal phenotype of the Mepraia species and carries out a comparison with the two species of Triatoma included in the spinolai complex (Triatoma eratyrusiformis and Triatoma breyeri). The analysis of the antennal phenotype of Mepraia showed a marked intraspecific phenotypic variability related with sex and wing condition. The number and length of multiporous trichoid sensilla (TH) on the pedicel are significantly higher and longer in winged males and are strongly reduced in females. The great length of the TH sensillum is an infrequent characteristic within Triatominae. The results show that phenetic distances between sexes are greater than between the two species. Similarity between the Mepraia species and T. eratyrusiformis was found as they all show long bristles (BR) and TH and two sized basiconic receptors (BA), a pattern that have not been observed in other species of Triatominae. These characters are not present in T. breyeri.

  19. Central Brain Circuitry for Color-Vision-Modulated Behaviors.

    Science.gov (United States)

    Longden, Kit D

    2016-10-24

    Color is famous for not existing in the external world: our brains create the perception of color from the spatial and temporal patterns of the wavelength and intensity of light. For an intangible quality, we have detailed knowledge of its origins and consequences. Much is known about the organization and evolution of the first phases of color processing, the filtering of light in the eye and processing in the retina, and about the final phases, the roles of color in behavior and natural selection. To understand how color processing in the central brain has evolved, we need well-defined pathways or circuitry where we can gauge how color contributes to the computations involved in specific behaviors. Examples of such pathways or circuitry that are dedicated to processing color cues are rare, despite the separation of color and luminance pathways early in the visual system of many species, and despite the traditional definition of color as being independent of luminance. This minireview presents examples in which color vision contributes to behaviors dominated by other visual modalities, examples that are not part of the canon of color vision circuitry. The pathways and circuitry process a range of chromatic properties of objects and their illumination, and are taken from a variety of species. By considering how color processing complements luminance processing, rather than being independent of it, we gain an additional way to account for the diversity of color coding in the central brain, its consequences for specific behaviors and ultimately the evolution of color vision. Copyright © 2016 Elsevier Ltd. All rights reserved.

  20. Phenotypic differentiation and phylogenetic signal of wing shape in western European biting midges, Culicoides spp., of the subgenus Avaritia

    DEFF Research Database (Denmark)

    Muñoz-Muñoz, F.; Talavera, S.; Carpenter, S.

    2014-01-01

    of the subgenus Avaritia were considered in the study (C. obsoletus (Meigen); C. scoticus Kettle and Lawson; C. chiopterus (Meigen); C. dewulfi Goetghebuer and C. imicola (Kieffer)). The study demonstrated that over 90% of individuals could be separated correctly into species by their wing shape and that patterns...

  1. The Trojan Color Conundrum

    Science.gov (United States)

    Jewitt, David

    2018-02-01

    The Trojan asteroids of Jupiter and Neptune are likely to have been captured from original heliocentric orbits in the dynamically excited (“hot”) population of the Kuiper Belt. However, it has long been known that the optical color distributions of the Jovian Trojans and the hot population are not alike. This difference has been reconciled with the capture hypothesis by assuming that the Trojans were resurfaced (for example, by sublimation of near-surface volatiles) upon inward migration from the Kuiper Belt (where blackbody temperatures are ∼40 K) to Jupiter’s orbit (∼125 K). Here, we examine the optical color distribution of the Neptunian Trojans using a combination of new optical photometry and published data. We find a color distribution that is statistically indistinguishable from that of the Jovian Trojans but unlike any sub-population in the Kuiper Belt. This result is puzzling, because the Neptunian Trojans are very cold (blackbody temperature ∼50 K) and a thermal process acting to modify the surface colors at Neptune’s distance would also affect the Kuiper Belt objects beyond, where the temperatures are nearly identical. The distinctive color distributions of the Jovian and Neptunian Trojans thus present us with a conundrum: they are very similar to each other, suggesting either capture from a common source or surface modification by a common process. However, the color distributions differ from any plausible common source population, and there is no known modifying process that could operate equally at both Jupiter and Neptune.

  2. From Color Code to Color Cue: Remembering Graphic Information.

    Science.gov (United States)

    Pruisner, Peggy A. P.

    This paper reports on a study which was conducted to determine the impact of color on learning. The entire seventh-grade class from a Midwest junior high school was used in the study. Each student was randomly assigned into one of four treatment groups: (1) color-cued presentation, color-cued assessment; (2) color-cued presentation, black/white…

  3. Luminance contours can gate afterimage colors and 'real' colors

    NARCIS (Netherlands)

    Anstis, S.; Vergeer, M.L.T.; Lier, R.J. van

    2012-01-01

    It has long been known that colored images may elicit afterimages in complementary colors. We have already shown (Van Lier, Vergeer, & Anstis, 2009) that one and the same adapting image may result in different afterimage colors, depending on the test contours presented after the colored image. The

  4. Color planner for designers based on color emotions

    Science.gov (United States)

    Cheng, Ka-Man; Xin, John H.; Taylor, Gail

    2002-06-01

    During the color perception process, an associated feeling or emotion is induced in our brains, and this kind of emotion is termed as 'color emotion.' The researchers in the field of color emotions have put many efforts in quantifying color emotions with the standard color specifications and evaluating the influence of hue, lightness and chroma to the color emotions of human beings. In this study, a color planner was derived according to these findings so that the correlation of color emotions and standard color specifications was clearly indicated. Since people of different nationalities usually have different color emotions as different cultural and traditional backgrounds, the subjects in this study were all native Hong Kong Chinese and the color emotion words were all written in Chinese language in the visual assessments. Through the color planner, the designers from different areas, no matter fashion, graphic, interior or web site etc., can select suitable colors for inducing target color emotions to the customers or product-users since different colors convey different meanings to them. In addition, the designers can enhance the functionality and increase the attractiveness of their designed products by selecting suitable colors.

  5. Single sensor processing to obtain high resolution color component signals

    Science.gov (United States)

    Glenn, William E. (Inventor)

    2010-01-01

    A method for generating color video signals representative of color images of a scene includes the following steps: focusing light from the scene on an electronic image sensor via a filter having a tri-color filter pattern; producing, from outputs of the sensor, first and second relatively low resolution luminance signals; producing, from outputs of the sensor, a relatively high resolution luminance signal; producing, from a ratio of the relatively high resolution luminance signal to the first relatively low resolution luminance signal, a high band luminance component signal; producing, from outputs of the sensor, relatively low resolution color component signals; and combining each of the relatively low resolution color component signals with the high band luminance component signal to obtain relatively high resolution color component signals.

  6. Segregation ratios of colored grains in F1 hybrid wheat

    Directory of Open Access Journals (Sweden)

    Zifeng Guo

    2012-01-01

    Full Text Available Nutritious and functional foods from wheat have received great attention in recent years. Colored-grain wheat contains a large number of nutrients such as anthocyanins and hence the breeding is interesting. In this work, colored-grained wheat lines of mixed pollination of einkorn wheat (Triticum boeoticum, AA and French rye (French Secale cereale, RR were used as male parents and wheat line Y1642 (derived from common wheat and Agropyron elongatum, AABBDD was used as the female parent. These colored wheat were used for diallel cross to study the segregation ratios of F1 colored grains. Results show that the color inheritance of purple-grained wheat follows a maternal inheritance pattern and that the blue-grained wheat expresses xenia in most cases. In some circumstances, the grains with different color shades appear in the same spike.

  7. Music-color associations are mediated by emotion.

    Science.gov (United States)

    Palmer, Stephen E; Schloss, Karen B; Xu, Zoe; Prado-León, Lilia R

    2013-05-28

    Experimental evidence demonstrates robust cross-modal matches between music and colors that are mediated by emotional associations. US and Mexican participants chose colors that were most/least consistent with 18 selections of classical orchestral music by Bach, Mozart, and Brahms. In both cultures, faster music in the major mode produced color choices that were more saturated, lighter, and yellower whereas slower, minor music produced the opposite pattern (choices that were desaturated, darker, and bluer). There were strong correlations (0.89 music and those of the colors chosen to go with the music, supporting an emotional mediation hypothesis in both cultures. Additional experiments showed similarly robust cross-modal matches from emotionally expressive faces to colors and from music to emotionally expressive faces. These results provide further support that music-to-color associations are mediated by common emotional associations.

  8. Color quality improvement of reconstructed images in color digital holography using speckle method and spectral estimation

    Science.gov (United States)

    Funamizu, Hideki; Onodera, Yusei; Aizu, Yoshihisa

    2018-05-01

    In this study, we report color quality improvement of reconstructed images in color digital holography using the speckle method and the spectral estimation. In this technique, an object is illuminated by a speckle field and then an object wave is produced, while a plane wave is used as a reference wave. For three wavelengths, the interference patterns of two coherent waves are recorded as digital holograms on an image sensor. Speckle fields are changed by moving a ground glass plate in an in-plane direction, and a number of holograms are acquired to average the reconstructed images. After the averaging process of images reconstructed from multiple holograms, we use the Wiener estimation method for obtaining spectral transmittance curves in reconstructed images. The color reproducibility in this method is demonstrated and evaluated using a Macbeth color chart film and staining cells of onion.

  9. Identification of the species of the Cheilosia variabilis group (Diptera, Syrphidae) from the Balkan Peninsula using wing geometric morphometrics, with the revision of status of C. melanopa redi Vujic, 1996

    NARCIS (Netherlands)

    Francuski, Lj.; Vujic, A.; Kovacevic, A.; Ludoski, J.; Milankov, V.

    2009-01-01

    The present study investigates phenotypic differentiation patterns among four species of the Cheilosia variabilis group (Diptera, Syrphidae) using a landmark-based geometric morphometric approach. Herein, wing geometric morphometrics established species boundaries that confirm C. melanopa and C.

  10. POSTMORTEM DIAGNOSIS OF ONE POPULATION OF BLUE-WINGED TEAL (Anas discors IN THE STATE OF VERACRUZ

    Directory of Open Access Journals (Sweden)

    Lorena López-De-Buen

    2011-11-01

    Full Text Available The health status of 30 Blue-winged Teal (Anas discors hunted in Amatitlán, in the central region of the state of Veracruz, Mexico, was assessed. The ducks were weighed, the wings were morphometrically measured, and of each organ the appearance, weight and length were evaluated, making comparisons between males and females, and between adults and immatures. The males weighed more than the females (n = 30, F(1,28 = 9.525, P = 0.004 and the adults more than the immatures (n = 19, F(1,17 = 6.526, P = 0.020. In all the groups the length of the wings was similar, as well as the internal organs had normal color, texture and location. The weight and size of lungs (5.4 g, 441 mm, liver (8.8 g, 608 mm, pancreas (1.5 g, 572 mm, gizzard (20.03 g, 448 mm and intestines (21 g were also similar among groups; however, the heart (3.8 g, 290 mm was larger in the males (n = 30, F(1,28 = 13.513, P = 0.0009, and the kidneys (3 g, 505 mm were heavier in the immature males (n = 19, F(1,17 = 7.417, P = 0.014. It was concluded that the Blue-winged Teal were in good health when hunted.

  11. Structural color painting by rubbing particle powder.

    Science.gov (United States)

    Park, ChooJin; Koh, Kunsuk; Jeong, Unyong

    2015-02-09

    Structural colors originate from purely physical structures. Scientists have been inspired to mimic the structures found in nature, the realization of these structures still presents a great challenge. We have recently introduced unidirectional rubbing of a dry particle powder on a rubbery surface as a quick, highly reproducible means to fabricate a single crystal monolayer assembly of particles over an unlimited area. This study extends the particle-rubbing process to a novel fine-art painting, structural color painting (SCP). SCP is based on structural coloring with varying iridescence according to the crystal orientation, as controlled by the rubbing direction. This painting technique can be applied on curved surfaces, which enriches the objects to be painted and helps the painter mimic the structures found in nature. It also allows for quick fabrication of complicated particle-assembly patterns, which enables replication of paintings.

  12. Gapless Color-Flavor-Locked Quark Matter

    DEFF Research Database (Denmark)

    Alford, Mark; Kouvaris, Christoforos; Rajagopal, Krishna

    2004-01-01

    In neutral cold quark matter that is sufficiently dense that the strange quark mass M_s is unimportant, all nine quarks (three colors; three flavors) pair in a color-flavor locked (CFL) pattern, and all fermionic quasiparticles have a gap. We argue that as a function of decreasing quark chemical...... a linear combination Qtilde of electric and color charges, but it is a Qtilde-conductor with a nonzero electron density. These electrons and the gapless quark quasiparticles make the low energy effective theory of the gapless CFL phase and, consequently, its astrophysical properties are qualitatively...... different from those of the CFL phase, even though its U(1) symmetries are the same. Both gapless quasiparticles have quadratic dispersion relations at the quantum critical point. For values of M_s^2/mu above the quantum critical point, one branch has conventional linear dispersion relations while the other...

  13. Is pushing the wall, the best known method for scapular winging, really the best? A Comparative analysis of various methods in neuromuscular disorders.

    Science.gov (United States)

    Khadilkar, Satish V; Chaudhari, Chetan R; Soni, Girish; Bhutada, Ashish

    2015-04-15

    'Pushing the wall' has found acceptance in medical teachings. Other methods of scapular winging are less known. Comparative evaluation of the five available methods has not been undertaken. This study focuses on evaluation of the available methods in groups of neuromuscular disorders to select the most sensitive method and to characterize patterns of scapular winging. A survey of methods practiced by clinicians also forms a part of the study. Prospective study. Part A: questionnaire based survey of clinicians to explore the preferred method of examination for scapular winging. Part B: comparative analysis of five methods of scapular winging in four categories of neuromuscular disorders [facioscapulohumeral muscular dystrophy (FSHD), limb girdle muscular dystrophy, dystrophinopathies and neurogenic disorders]. Forward lowering of arms was the most sensitive method [100%]. The use of this method in clinical teachings and routine bedside examination should be promoted. Pushing the wall was the most popular method, but was fourth in the sensitivity [60.41%]. Arm maneuvers can bring out winging, when it is not apparent at rest. FSHD patients had a unique combination of winging at rest, persistence of winging throughout the range of motion and elevation of scapulae. Copyright © 2015 Elsevier B.V. All rights reserved.

  14. The Banded-wing Moselia infuscata (Claassen) Phenotype from California and Oregon, U.S.A. (Plecoptera: Leuctridae).

    Science.gov (United States)

    Gill, Brian A; Kondratieff, Boris C; Stark, Bill P; Sandberg, John B

    2015-01-21

    Moselia specimens from California and Oregon with a banded-wing phenotype were found to be indistinguishable morphologically from those of M. infuscata (Claassen) with typical wing pigment pattern. Preliminary DNA barcode data (Cytochrome c Oxidase subunit I [COI]), however, show significant genetic variation among four populations including three from northern California sites and one from southern Oregon. Although this genetic variation exceeded standard divergence thresholds often used to recognize distinct stream insect species, no new taxa are proposed at this time due to the preliminary nature of the data. 

  15. Structural color of a lycaenid butterfly: analysis of an aperiodic multilayer structure.

    Science.gov (United States)

    Yoshioka, S; Shimizu, Y; Kinoshita, S; Matsuhana, B

    2013-12-01

    We investigated the structural color of the green wing of the lycaenid butterfly Chrysozephyrus brillantinus. Electron microscopy revealed that the bottom plate of the cover scale on the wing consists of an alternating air-cuticle multilayer structure. However, the thicknesses of the layers were not constant but greatly differed depending on the layer, unlike the periodic multilayer designs often adopted for artificial laser-reflecting mirrors. The agreement between the experimentally determined and theoretically calculated reflectance spectra led us to conclude that the multilayer interference in the aperiodic system is the primary origin of the structural color. We analyzed optical interference in this aperiodic system using a simple analytical model and found that two spectral peaks arise from constructive interference among different parts of the multilayer structure. We discuss the advantages and disadvantages of the aperiodic system over a periodic one.

  16. Nurses' uniform color and feelings/emotions in school-aged children receiving health care.

    Science.gov (United States)

    Albert, Nancy M; Burke, Jane; Bena, James F; Morrison, Shannon M; Forney, Jennifer; Krajewski, Susan

    2013-04-01

    Children may fear nurses wearing white uniforms. When emotions and uniform color were studied in 233 children, many positive emotions were most often associated with blue, bold pink-patterned, or yellow-patterned tops (all p ≤ .002). Negative emotions were not associated with uniform top colors (all p uniform color does not matter," 8 negative emotions were most often associated with white uniform color (p uniform tops were preferred. In conclusion, children's emotions were associated with nurse uniform color. Copyright © 2013 Elsevier Inc. All rights reserved.

  17. The optimal design of UAV wing structure

    Science.gov (United States)

    Długosz, Adam; Klimek, Wiktor

    2018-01-01

    The paper presents an optimal design of UAV wing, made of composite materials. The aim of the optimization is to improve strength and stiffness together with reduction of the weight of the structure. Three different types of functionals, which depend on stress, stiffness and the total mass are defined. The paper presents an application of the in-house implementation of the evolutionary multi-objective algorithm in optimization of the UAV wing structure. Values of the functionals are calculated on the basis of results obtained from numerical simulations. Numerical FEM model, consisting of different composite materials is created. Adequacy of the numerical model is verified by results obtained from the experiment, performed on a tensile testing machine. Examples of multi-objective optimization by means of Pareto-optimal set of solutions are presented.

  18. Adjoint-based optimization for flapping wings

    Science.gov (United States)

    Xu, Min; Wei, Mingjun

    2012-11-01

    Adjoint-based methods show great potential in flow control and optimization of complex problems with high- or infinite-dimensional control space. It is attractive to solve an adjoint problem to understand the complex effects from multiple control parameters to a few performance indicators of the flight of birds or insects. However, the traditional approach to formulate the adjoint problem becomes either impossible or too complex when arbitrary moving boundary (e.g. flapping wings) and its perturbation is considered. Here, we use non-cylindrical calculus to define the perturbation. So that, a simple adjoint system can be derived directly in the inertial coordinate. The approach is first applied to the optimization of cylinder oscillation and later to flapping wings. Supported by AFOSR.

  19. Quantifying the dynamic wing morphing of hovering hummingbird.

    Science.gov (United States)

    Maeda, Masateru; Nakata, Toshiyuki; Kitamura, Ikuo; Tanaka, Hiroto; Liu, Hao

    2017-09-01

    Animal wings are lightweight and flexible; hence, during flapping flight their shapes change. It has been known that such dynamic wing morphing reduces aerodynamic cost in insects, but the consequences in vertebrate flyers, particularly birds, are not well understood. We have developed a method to reconstruct a three-dimensional wing model of a bird from the wing outline and the feather shafts (rachides). The morphological and kinematic parameters can be obtained using the wing model, and the numerical or mechanical simulations may also be carried out. To test the effectiveness of the method, we recorded the hovering flight of a hummingbird ( Amazilia amazilia ) using high-speed cameras and reconstructed the right wing. The wing shape varied substantially within a stroke cycle. Specifically, the maximum and minimum wing areas differed by 18%, presumably due to feather sliding; the wing was bent near the wrist joint, towards the upward direction and opposite to the stroke direction; positive upward camber and the 'washout' twist (monotonic decrease in the angle of incidence from the proximal to distal wing) were observed during both half-strokes; the spanwise distribution of the twist was uniform during downstroke, but an abrupt increase near the wrist joint was found during upstroke.

  20. Optimization of aerodynamic efficiency for twist morphing MAV wing

    Directory of Open Access Journals (Sweden)

    N.I. Ismail

    2014-06-01

    Full Text Available Twist morphing (TM is a practical control technique in micro air vehicle (MAV flight. However, TM wing has a lower aerodynamic efficiency (CL/CD compared to membrane and rigid wing. This is due to massive drag penalty created on TM wing, which had overwhelmed the successive increase in its lift generation. Therefore, further CL/CDmax optimization on TM wing is needed to obtain the optimal condition for the morphing wing configuration. In this paper, two-way fluid–structure interaction (FSI simulation and wind tunnel testing method are used to solve and study the basic wing aerodynamic performance over (non-optimal TM, membrane and rigid wings. Then, a multifidelity data metamodel based design optimization (MBDO process is adopted based on the Ansys-DesignXplorer frameworks. In the adaptive MBDO process, Kriging metamodel is used to construct the final multifidelity CL/CD responses by utilizing 23 multi-fidelity sample points from the FSI simulation and experimental data. The optimization results show that the optimal TM wing configuration is able to produce better CL/CDmax magnitude by at least 2% than the non-optimal TM wings. The flow structure formation reveals that low TV strength on the optimal TM wing induces low CD generation which in turn improves its overall CL/CDmax performance.

  1. CFD Analysis of UAV Flying Wing

    Directory of Open Access Journals (Sweden)

    Vasile PRISACARIU

    2016-09-01

    Full Text Available Numerical methods for solving equations describing the evolution of 3D fluid experienced a significant development closely related to the progress of information systems. Today, especially in the field of fluid mechanics, numerical simulations allow the study of gas-thermodynamic confirmed by experimental techniques in wind tunnel conditions and actual flight tests for modeling complex aircraft. The article shows a case of numerical analysis of the lifting surface on the UAV type flying wing.

  2. Topology Optimization of an Aircraft Wing

    Science.gov (United States)

    2015-06-11

    can combine the advantages of a variable stiffness design with- out the use of actuators. Curved beams, which couple torsion and bending , counteract... torsional deflection, control natural frequency, exploit coupling of bending and tor- sion to control flutter, reduce thickness to chord ratios due to...disregarded any bending or torsional effects caused by displacement of the wing, and was thus not considered. Therefore, the initial design analysis

  3. On dominator colorings in graphs

    Indian Academy of Sciences (India)

    A dominator coloring of a graph G is a proper coloring of G in which every vertex dominates every vertex of at least one color class. The minimum number of colors required for a dominator coloring of G is called the dominator chromatic number of G and is denoted by χd(G). In this paper we present several results on graphs ...

  4. Tracing the evolution of avian wing digits.

    Science.gov (United States)

    Xu, Xing; Mackem, Susan

    2013-06-17

    It is widely accepted that birds are a subgroup of dinosaurs, but there is an apparent conflict: modern birds have been thought to possess only the middle three fingers (digits II-III-IV) of an idealized five-digit tetrapod hand based on embryological data, but their Mesozoic tetanuran dinosaur ancestors are considered to have the first three digits (I-II-III) based on fossil evidence. How could such an evolutionary quirk arise? Various hypotheses have been proposed to resolve this paradox. Adding to the confusion, some recent developmental studies support a I-II-III designation for avian wing digits whereas some recent paleontological data are consistent with a II-III-IV identification of the Mesozoic tetanuran digits. A comprehensive analysis of both paleontological and developmental data suggests that the evolution of the avian wing digits may have been driven by homeotic transformations of digit identity, which are more likely to have occurred in a partial and piecemeal manner. Additionally, recent genetic studies in mouse models showing plausible mechanisms for central digit loss invite consideration of new alternative possibilities (I-II-IV or I-III-IV) for the homologies of avian wing digits. While much progress has been made, some advances point to the complexity of the problem and a final resolution to this ongoing debate demands additional work from both paleontological and developmental perspectives, which will surely yield new insights on mechanisms of evolutionary adaptation. Copyright © 2013 Elsevier Ltd. All rights reserved.

  5. Unsteady fluid dynamics around a hovering wing

    Science.gov (United States)

    Krishna, Swathi; Green, Melissa; Mulleners, Karen

    2017-11-01

    The unsteady flow around a hovering flat plate wing has been investigated experimentally using particle image velocimetry and direct force measurements. The measurements are conducted on a wing that rotates symmetrically about the stroke reversal at a reduced frequency of k = 0.32 and Reynolds number of Re = 220 . The Lagrangian finite-time Lyapunov exponent method is used to analyse the unsteady flow fields by identifying dynamically relevant flow features such as the primary leading edge vortex (LEV), secondary vortices, and topological saddles, and their evolution within a flapping cycle. The flow evolution is divided into four stages that are characterised by the LEV (a)emergence, (b)growth, (c)lift-off, and (d)breakdown and decay. Tracking saddle points is shown to be helpful in defining the LEV lift-off which occurs at the maximum stroke velocity. The flow fields are correlated with the aerodynamic forces revealing that the maximum lift and drag are observed just before LEV lift-off. The end of wing rotation in the beginning of the stroke stimulates a change in the direction of the LEV growth and the start of rotation at the end of the stroke triggers the breakdown of the LEV.

  6. Color Memory of University Students: Influence of Color Experience and Color Characteristic

    Science.gov (United States)

    Bynum, Carlisle; Epps, Helen H.; Kaya, Naz

    2006-01-01

    The ability to select a previously viewed color specimen from an array of specimens that differ in hue, value, or chroma varies among individuals, and may be related to one's basic color discrimination ability or to prior experience with color. This study investigated short-term color memory of 40 college students, 20 of whom were interior design…

  7. Precision of Synesthetic Color Matching Resembles That for Recollected Colors Rather than Physical Colors

    Science.gov (United States)

    Arnold, Derek H.; Wegener, Signy V.; Brown, Francesca; Mattingley, Jason B.

    2012-01-01

    Grapheme-color synesthesia is an atypical condition in which individuals experience sensations of color when reading printed graphemes such as letters and digits. For some grapheme-color synesthetes, seeing a printed grapheme triggers a sensation of color, but "hearing" the name of a grapheme does not. This dissociation allowed us to…

  8. Color in Reference Production: The Role of Color Similarity and Color Codability.

    Science.gov (United States)

    Viethen, Jette; van Vessem, Thomas; Goudbeek, Martijn; Krahmer, Emiel

    2017-05-01

    It has often been observed that color is a highly preferred attribute for use in distinguishing descriptions, that is, referring expressions produced with the purpose of identifying an object within a visual scene. However, most of these observations were based on visual displays containing only colors that were maximally different in hue and for which the language of experimentation possessed basic color terms. The experiments described in this paper investigate whether speakers' preference for color is reduced if the color of the target referent is similar to that of the distractors. Because colors that look similar are often also harder to distinguish linguistically, we also examine the impact of the codability of color values. As a third factor, we investigate the salience of available alternative attributes and its impact on the use of color. The results of our experiments show that, while speakers are indeed less likely to use color when the colors in a display are similar, this effect is mostly due to the difficulty in naming similar colors. Color use for color with a basic color term is affected only when the colors of target and distractors are very similar (yet still distinguishable). The salience of our alternative attribute size, manipulated by varying the difference in size between target and distractors, had no impact on the use of color. Copyright © 2016 Cognitive Science Society, Inc.

  9. Wing and body kinematics of takeoff and landing flight in the pigeon (Columba livia).

    Science.gov (United States)

    Berg, Angela M; Biewener, Andrew A

    2010-05-01

    Takeoff and landing are critical phases in a flight. To better understand the functional importance of the kinematic adjustments birds use to execute these flight modes, we studied the wing and body movements of pigeons (Columba livia) during short-distance free-flights between two perches. The greatest accelerations were observed during the second wingbeat of takeoff. The wings were responsible for the majority of acceleration during takeoff and landing, with the legs contributing only one-quarter of the acceleration. Parameters relating to aerodynamic power output such as downstroke amplitude, wingbeat frequency and downstroke velocity were all greatest during takeoff flight and decreased with each successive takeoff wingbeat. This pattern indicates that downstroke velocity must be greater for accelerating flight to increase the amount of air accelerated by the wings. Pigeons used multiple mechanisms to adjust thrust and drag to accelerate during takeoff and decelerate during landing. Body angle, tail angle and wing plane angles all shifted from more horizontal orientations during takeoff to near-vertical orientations during landing, thereby reducing drag during takeoff and increasing drag during landing. The stroke plane was tilted steeply downward throughout takeoff (increasing from -60+/-5 deg. to -47+/-1 deg.), supporting our hypothesis that a downward-tilted stroke plane pushes more air rearward to accelerate the bird forward. Similarly, the stroke plane tilted upward during landing (increasing from -1+/-2 deg. to 17+/-7 deg.), implying that an upward-tilted stroke plane pushes more air forward to slow the bird down. Rotations of the stroke plane, wing planes and tail were all strongly correlated with rotation of the body angle, suggesting that pigeons are able to redirect aerodynamic force and shift between flight modes through modulation of body angle alone.

  10. The color "fruit": object memories defined by color.

    Science.gov (United States)

    Lewis, David E; Pearson, Joel; Khuu, Sieu K

    2013-01-01

    Most fruits and other highly color-diagnostic objects have color as a central aspect of their identity, which can facilitate detection and visual recognition. It has been theorized that there may be a large amount of overlap between the neural representations of these objects and processing involved in color perception. In accordance with this theory we sought to determine if the recognition of highly color diagnostic fruit objects could be facilitated by the visual presentation of their known color associates. In two experiments we show that color associate priming is possible, but contingent upon multiple factors. Color priming was found to be maximally effective for the most highly color diagnostic fruits, when low spatial-frequency information was present in the image, and when determination of the object's specific identity, not merely its category, was required. These data illustrate the importance of color for determining the identity of certain objects, and support the theory that object knowledge involves sensory specific systems.

  11. Intra-specific pelage color variation in a South American small rodent species

    OpenAIRE

    Sandoval Salinas,M. L.; Barquez,R. M.; Colombo,E. M.; Sandoval,J. D.

    2017-01-01

    Abstract Intra-specific color variation is often underestimated by researchers, and among mammals, intra-specific differences in coloration are poorly documented for most species. The main goal of this study was to apply an objective color measurement methodology to the study of a specific problem: the detection, if any, of patterns of changes in the fur color of specimens of Akodon budini in relation to biological (i.e., sex) and environmental (i.e., season) variables. We hypothesize that co...

  12. Intra-specific pelage color variation in a South American small rodent species

    OpenAIRE

    Sandoval Salinas, M. L.; Barquez, R. M.; Colombo, E. M.; Sandoval, J. D.

    2016-01-01

    Abstract Intra-specific color variation is often underestimated by researchers, and among mammals, intra-specific differences in coloration are poorly documented for most species. The main goal of this study was to apply an objective color measurement methodology to the study of a specific problem: the detection, if any, of patterns of changes in the fur color of specimens of Akodon budini in relation to biological (i.e., sex) and environmental (i.e., season) variables. We hypothesize that co...

  13. The color of money

    DEFF Research Database (Denmark)

    Ásgeirsson, Árni Gunnar; Kristjánsson, Árni; Einarsdóttir, Kristin Vala

    2014-01-01

    of attention are affected by reward, and whether the effect involves general enhancement or is specific to discrete components of attention. Observers viewed brief displays of differentially colored letters and reported their identity. Each color signified a consistent monetary value and we measured....... Importantly, our design was balanced so that the expected utility of uninformed guessing was zero, yielding no incentive to employ value-dependent response criteria. We also tested value-dependent effects on the capacity of visual-short term memory. Finally, we tested for motivational salience effects......, by including conditions with color-contingent negative values. This gave an opportunity to compare high-gain with high-loss conditions. We found clear effects of value on selectivity when comparing high- and low-value conditions. When comparing equally valuable high-loss and high-gain conditions there were...

  14. PHOTOGRAMMETRIC MEASUREMENTS IN FIXED WING UAV IMAGERY

    Directory of Open Access Journals (Sweden)

    E. Gülch

    2012-07-01

    Full Text Available Several flights have been undertaken with PAMS (Photogrammetric Aerial Mapping System by Germap, Germany, which is briefly introduced. This system is based on the SmartPlane fixed-wing UAV and a CANON IXUS camera system. The plane is equipped with GPS and has an infrared sensor system to estimate attitude values. A software has been developed to link the PAMS output to a standard photogrammetric processing chain built on Trimble INPHO. The linking of the image files and image IDs and the handling of different cases with partly corrupted output have to be solved to generate an INPHO project file. Based on this project file the software packages MATCH-AT, MATCH-T DSM, OrthoMaster and OrthoVista for digital aerial triangulation, DTM/DSM generation and finally digital orthomosaik generation are applied. The focus has been on investigations on how to adapt the "usual" parameters for the digital aerial triangulation and other software to the UAV flight conditions, which are showing high overlaps, large kappa angles and a certain image blur in case of turbulences. It was found, that the selected parameter setup shows a quite stable behaviour and can be applied to other flights. A comparison is made to results from other open source multi-ray matching software to handle the issue of the described flight conditions. Flights over the same area at different times have been compared to each other. The major objective was here to see, on how far differences occur relative to each other, without having access to ground control data, which would have a potential for applications with low requirements on the absolute accuracy. The results show, that there are influences of weather and illumination visible. The "unusual" flight pattern, which shows big time differences for neighbouring strips has an influence on the AT and DTM/DSM generation. The results obtained so far do indicate problems in the stability of the camera calibration. This clearly requests a

  15. First discovery of fossil winged seeds of Pinus L. (family Pinaceae) from the Indian Cenozoic and its palaeobiogeographic significance

    Science.gov (United States)

    Khan, Mahasin Ali; Bera, Subir

    2017-07-01

    The occurrences of Pinus L. (family Pinaceae) megafossils (cones and leaf remains) have been abundantly documented from the Cenozoic sediments of eastern Asia (Japan and China), but none has been confirmed from the Indian Cenozoic till date. Here, we describe Pinus arunachalensis Khan and Bera, sp. nov. on the basis of seed remains from the middle to late Miocene Siwalik sediments of the Dafla Formation exposed around West Kameng district in Arunachal Pradesh, eastern Himalaya. Seeds are winged, broadly oblong to oval in outline, 1.3-1.5 cm long and 0.4-0.6 cm broad (in the middle part), located basipetally and symmetrically to wing, cellular pattern of wing is seemingly undulatory and parallel with the long axis of the wing. So far, this report provides the first ever fossil record of Pinus winged seeds from India. This record suggests that Pinus was an important component of tropical-subtropical evergreen forest in the area during the Miocene and this group subsequently declined from the local vegetation probably because of the gradual intensification of MSI (monsoon index) from the Miocene to the present. We also review the historical phytogeography and highlight the phytogeographic implication of this genus.

  16. Future of color

    Science.gov (United States)

    Ladson, Jack A.; Turner, Laraine B.; Green-Armytage, Paul; Hunt, Robert W. G.

    2002-06-01

    We live in a world in which styles and technologies are nearly the same from place to place, but change daily. This changing global culture is unprecedented, and reinforced by emerging new technologies that affect us all. The Future of Color, examines new technologies, how they will affect the selection and promulgation of color in the near future, and their impact upon us. We examine this topic from many perspectives - technological, business and commercial. Most importantly, as we understand how our world is emerging, we can position ourselves strategically for tomorrow.

  17. Plate Full of Color

    Centers for Disease Control (CDC) Podcasts

    2008-08-04

    The Eagle Books are a series of four books that are brought to life by wise animal characters - Mr. Eagle, Miss Rabbit, and Coyote - who engage Rain That Dances and his young friends in the joy of physical activity, eating healthy foods, and learning from their elders about health and diabetes prevention. Plate Full of Color teaches the value of eating a variety of colorful and healthy foods.  Created: 8/4/2008 by National Center for Chronic Disease Prevention and Health Promotion (NCCDPHP).   Date Released: 8/5/2008.

  18. Wing geometry of Triatoma sordida (Hemiptera: Reduviidae) populations from Brazil.

    Science.gov (United States)

    Vendrami, Daniel Pagotto; Obara, Marcos Takashi; Gurgel-Gonçalves, Rodrigo; Ceretti-Junior, Walter; Marrelli, Mauro Toledo

    2017-04-01

    Triatoma sordida has a widespread distribution in Argentina, Bolivia, Brazil, Paraguay, and Uruguay and is frequently found in peridomestic environments. We investigated size and shape variability of T. sordida wings across Brazil. Field-collected adults from twelve populations were studied. For each individual female, seven landmarks on the right wing were digitalized. Shape variables derived from Procrustes superimposition were used in Principal Component Analysis (PCA). Wing size and shape variations among populations was explored by means of ANOVA. Wing centroid size was significantly different among T. sordida populations; specimens from Bahia (East) were larger than those of Mato Grosso do Sul (West). PCA based on wing shape variables showed low wing shape variability. These results reinforce previous data showing low genetic variability among T. sordida populations from Brazil. Copyright © 2017 Elsevier B.V. All rights reserved.

  19. Measurement of shape and deformation of insect wing

    Science.gov (United States)

    Yin, Duo; Wei, Zhen; Wang, Zeyu; Zhou, Changqiu

    2018-01-01

    To measure the shape and deformation of an insect wing, a scanning setup adopting laser triangulation and image matching was developed. Only one industry camera with two light sources was employed to scan the transparent insect wings. 3D shape and point to point full field deformation of the wings could be obtained even when the wingspan is less than 3 mm. The venation and corrugation could be significantly identified from the results. The deformation of the wing under pin loading could be seen clearly from the results as well. Calibration shows that the shape and deformation measurement accuracies are no lower than 0.01 mm. Laser triangulation and image matching were combined dexterously to adapt wings' complex shape, size, and transparency. It is suitable for insect flight research or flapping wing micro-air vehicle development.

  20. Scaling the Drosophila Wing: TOR-Dependent Target Gene Access by the Hippo Pathway Transducer Yorkie.

    Science.gov (United States)

    Parker, Joseph; Struhl, Gary

    2015-10-01

    Organ growth is controlled by patterning signals that operate locally (e.g., Wingless/Ints [Wnts], Bone Morphogenetic Proteins [BMPs], and Hedgehogs [Hhs]) and scaled by nutrient-dependent signals that act systemically (e.g., Insulin-like peptides [ILPs] transduced by the Target of Rapamycin [TOR] pathway). How cells integrate these distinct inputs to generate organs of the appropriate size and shape is largely unknown. The transcriptional coactivator Yorkie (Yki, a YES-Associated Protein, or YAP) acts downstream of patterning morphogens and other tissue-intrinsic signals to promote organ growth. Yki activity is regulated primarily by the Warts/Hippo (Wts/Hpo) tumour suppressor pathway, which impedes nuclear access of Yki by a cytoplasmic tethering mechanism. Here, we show that the TOR pathway regulates Yki by a separate and novel mechanism in the Drosophila wing. Instead of controlling Yki nuclear access, TOR signaling governs Yki action after it reaches the nucleus by allowing it to gain access to its target genes. When TOR activity is inhibited, Yki accumulates in the nucleus but is sequestered from its normal growth-promoting target genes--a phenomenon we term "nuclear seclusion." Hence, we posit that in addition to its well-known role in stimulating cellular metabolism in response to nutrients, TOR also promotes wing growth by liberating Yki from nuclear seclusion, a parallel pathway that we propose contributes to the scaling of wing size with nutrient availability.