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Sample records for prominent eyespot feathers

  1. Origin, development, and evolution of butterfly eyespots.

    Science.gov (United States)

    Monteiro, Antónia

    2015-01-07

    This article reviews the latest developments in our understanding of the origin, development, and evolution of nymphalid butterfly eyespots. Recent contributions to this field include insights into the evolutionary and developmental origin of eyespots and their ancestral deployment on the wing, the evolution of eyespot number and eyespot sexual dimorphism, and the identification of genes affecting eyespot development and black pigmentation. I also compare features of old and more recently proposed models of eyespot development and propose a schematic for the genetic regulatory architecture of eyespots. Using this schematic I propose two hypotheses for why we observe limits to morphological diversity across these serially homologous traits.

  2. Prediction of eyespot infection risks

    Directory of Open Access Journals (Sweden)

    M. Váòová

    2012-12-01

    Full Text Available The objective of the study was to design a prediction model for eyespot (Tapesia yallundae infection based on climatic factors (temperature, precipitation, air humidity. Data from experiment years 1994-2002 were used to study correlations between the eyespot infection index and individual weather characteristics. The model of prediction was constructed using multiple regression when a separate parameter is assigned to each factor, i.e. the frequency of days with optimum temperatures, humidity, and precipitation. The correlation between relative air humidity and precipitation and the infection index is significant.

  3. Marginal eyespots on butterfly wings deflect bird attacks under low light intensities with UV wavelengths.

    Directory of Open Access Journals (Sweden)

    Martin Olofsson

    2010-05-01

    Full Text Available Predators preferentially attack vital body parts to avoid prey escape. Consequently, prey adaptations that make predators attack less crucial body parts are expected to evolve. Marginal eyespots on butterfly wings have long been thought to have this deflective, but hitherto undemonstrated function.Here we report that a butterfly, Lopinga achine, with broad-spectrum reflective white scales in its marginal eyespot pupils deceives a generalist avian predator, the blue tit, to attack the marginal eyespots, but only under particular conditions-in our experiments, low light intensities with a prominent UV component. Under high light intensity conditions with a similar UV component, and at low light intensities without UV, blue tits directed attacks towards the butterfly head.In nature, birds typically forage intensively at early dawn, when the light environment shifts to shorter wavelengths, and the contrast between the eyespot pupils and the background increases. Among butterflies, deflecting attacks is likely to be particularly important at dawn when low ambient temperatures make escape by flight impossible, and when insectivorous birds typically initiate another day's search for food. Our finding that the deflective function of eyespots is highly dependent on the ambient light environment helps explain why previous attempts have provided little support for the deflective role of marginal eyespots, and we hypothesize that the mechanism that we have discovered in our experiments in a laboratory setting may function also in nature when birds forage on resting butterflies under low light intensities.

  4. Marginal eyespots on butterfly wings deflect bird attacks under low light intensities with UV wavelengths.

    Science.gov (United States)

    Olofsson, Martin; Vallin, Adrian; Jakobsson, Sven; Wiklund, Christer

    2010-05-24

    Predators preferentially attack vital body parts to avoid prey escape. Consequently, prey adaptations that make predators attack less crucial body parts are expected to evolve. Marginal eyespots on butterfly wings have long been thought to have this deflective, but hitherto undemonstrated function. Here we report that a butterfly, Lopinga achine, with broad-spectrum reflective white scales in its marginal eyespot pupils deceives a generalist avian predator, the blue tit, to attack the marginal eyespots, but only under particular conditions-in our experiments, low light intensities with a prominent UV component. Under high light intensity conditions with a similar UV component, and at low light intensities without UV, blue tits directed attacks towards the butterfly head. In nature, birds typically forage intensively at early dawn, when the light environment shifts to shorter wavelengths, and the contrast between the eyespot pupils and the background increases. Among butterflies, deflecting attacks is likely to be particularly important at dawn when low ambient temperatures make escape by flight impossible, and when insectivorous birds typically initiate another day's search for food. Our finding that the deflective function of eyespots is highly dependent on the ambient light environment helps explain why previous attempts have provided little support for the deflective role of marginal eyespots, and we hypothesize that the mechanism that we have discovered in our experiments in a laboratory setting may function also in nature when birds forage on resting butterflies under low light intensities.

  5. Focusing on butterfly eyespot focus: uncoupling of white spots from eyespot bodies in nymphalid butterflies.

    Science.gov (United States)

    Iwata, Masaki; Otaki, Joji M

    2016-01-01

    Developmental studies on butterfly wing color patterns often focus on eyespots. A typical eyespot (such as that of Bicyclus anynana) has a few concentric rings of dark and light colors and a white spot (called a focus) at the center. The prospective eyespot center during the early pupal stage is known to act as an organizing center. It has often been assumed, according to gradient models for positional information, that a white spot in adult wings corresponds to an organizing center and that the size of the white spot indicates how active that organizing center was. However, there is no supporting evidence for these assumptions. To evaluate the feasibility of these assumptions in nymphalid butterflies, we studied the unique color patterns of Calisto tasajera (Nymphalidae, Satyrinae), which have not been analyzed before in the literature. In the anterior forewing, one white spot was located at the center of an eyespot, but another white spot associated with either no or only a small eyespot was present in the adjacent compartment. The anterior hindwing contained two adjacent white spots not associated with eyespots, one of which showed a sparse pattern. The posterior hindwing contained two adjacent pear-shaped eyespots, and the white spots were located at the proximal side or even outside the eyespot bodies. The successive white spots within a single compartment along the midline in the posterior hindwing showed a possible trajectory of a positional determination process for the white spots. Several cases of focus-less eyespots in other nymphalid butterflies were also presented. These results argue for the uncoupling of white spots from eyespot bodies, suggesting that an eyespot organizing center does not necessarily differentiate into a white spot and that a prospective white spot does not necessarily signify organizing activity for an eyespot. Incorporation of these results in future models for butterfly wing color pattern formation is encouraged.

  6. Physiological Perturbation Reveals Modularity of Eyespot Development in the Painted Lady Butterfly, Vanessa cardui

    Science.gov (United States)

    Rhen, Turk; Simmons, Rebecca B.

    2016-01-01

    Butterfly eyespots are complex morphological traits that can vary in size, shape and color composition even on the same wing surface. Homology among eyespots suggests they share a common developmental basis and function as an integrated unit in response to selection. Despite strong evidence of genetic integration, eyespots can also exhibit modularity or plasticity, indicating an underlying flexibility in pattern development. The extent to which particular eyespots or eyespot color elements exhibit modularity or integration is poorly understood, particularly following exposure to novel conditions. We used perturbation experiments to explore phenotypic correlations among different eyespots and their color elements on the ventral hindwing of V. cardui. Specifically, we identified which eyespots and eyespot features are most sensitive to perturbation by heat shock and injection of heparin—a cold shock mimic. For both treatments, the two central eyespots (3 + 4) were most affected by the experimental perturbations, whereas the outer eyespot border was more resistant to modification than the interior color elements. Overall, the individual color elements displayed a similar response to heat shock across all eyespots, but varied in their response to each other. Graphical modeling also revealed that although eyespots differ morphologically, regulation of eyespot size and colored elements appear to be largely integrated across the wing. Patterns of integration, however, were disrupted following heat shock, revealing that the strength of integration varies across the wing and is strongest between the two central eyespots. These findings support previous observations that document coupling between eyespots 3 + 4 in other nymphalid butterflies. PMID:27560365

  7. Color-pattern analysis of eyespots in butterfly wings: a critical examination of morphogen gradient models.

    Science.gov (United States)

    Otaki, Joji M

    2011-06-01

    Butterfly wing color patterns consist of many color-pattern elements such as eyespots. It is believed that eyespot patterns are determined by a concentration gradient of a single morphogen species released by diffusion from the prospective eyespot focus in conjunction with multiple thresholds in signal-receiving cells. As alternatives to this single-morphogen model, more flexible multiple-morphogen model and induction model can be proposed. However, the relevance of these conceptual models to actual eyespots has not been examined systematically. Here, representative eyespots from nymphalid butterflies were analyzed morphologically to determine if they are consistent with these models. Measurement of ring widths of serial eyespots from a single wing surface showed that the proportion of each ring in an eyespot is quite different among homologous rings of serial eyespots of different sizes. In asymmetric eyespots, each ring is distorted to varying degrees. In extreme cases, only a portion of rings is expressed remotely from the focus. Similarly, there are many eyespots where only certain rings are deleted, added, or expanded. In an unusual case, the central area of an eyespot is composed of multiple "miniature eyespots," but the overall macroscopic eyespot structure is maintained. These results indicate that each eyespot ring has independence and flexibility to a certain degree, which is less consistent with the single-morphogen model. Considering a "periodic eyespot", which has repeats of a set of rings, damage-induced eyespots in mutants, and a scale-size distribution pattern in an eyespot, the induction model is the least incompatible with the actual eyespot diversity.

  8. 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.

  9. Solar prominences

    CERN Document Server

    Engvold, Oddbjørn

    2015-01-01

    This volume presents the latest research results on solar prominences, including new developments on e.g. chirality, fine structure, magnetism, diagnostic tools and relevant solar plasma physics. In 1875 solar prominences, as seen out of the solar limb, were described by P.A. Secchi in his book Le Soleil as "gigantic pink or peach-flower coloured flames". The development of spectroscopy, coronagraphy and polarimetry brought tremendous observational advances in the twentieth century. The authors present and discuss exciting new challenges (resulting from observations made by space and ground-based telescopes in the 1990s and the first decade of the 21st century) concerning the diagnostics of prominences, their formation, their life time and their eruption along with their impact in the heliosphere (including the Earth). The book starts with a general introduction of the prominence “object” with some historical background on observations and instrumentation. In the next chapter, the various forms of promine...

  10. Structural analysis of eyespots: dynamics of morphogenic signals that govern elemental positions in butterfly wings

    Directory of Open Access Journals (Sweden)

    Otaki Joji M

    2012-03-01

    Full Text Available Abstract Background To explain eyespot colour-pattern determination in butterfly wings, the induction model has been discussed based on colour-pattern analyses of various butterfly eyespots. However, a detailed structural analysis of eyespots that can serve as a foundation for future studies is still lacking. In this study, fundamental structural rules related to butterfly eyespots are proposed, and the induction model is elaborated in terms of the possible dynamics of morphogenic signals involved in the development of eyespots and parafocal elements (PFEs based on colour-pattern analysis of the nymphalid butterfly Junonia almana. Results In a well-developed eyespot, the inner black core ring is much wider than the outer black ring; this is termed the inside-wide rule. It appears that signals are wider near the focus of the eyespot and become narrower as they expand. Although fundamental signal dynamics are likely to be based on a reaction-diffusion mechanism, they were described well mathematically as a type of simple uniformly decelerated motion in which signals associated with the outer and inner black rings of eyespots and PFEs are released at different time points, durations, intervals, and initial velocities into a two-dimensional field of fundamentally uniform or graded resistance; this produces eyespots and PFEs that are diverse in size and structure. The inside-wide rule, eyespot distortion, structural differences between small and large eyespots, and structural changes in eyespots and PFEs in response to physiological treatments were explained well using mathematical simulations. Natural colour patterns and previous experimental findings that are not easily explained by the conventional gradient model were also explained reasonably well by the formal mathematical simulations performed in this study. Conclusions In a mode free from speculative molecular interactions, the present study clarifies fundamental structural rules related to

  11. Structural analysis of eyespots: dynamics of morphogenic signals that govern elemental positions in butterfly wings.

    Science.gov (United States)

    Otaki, Joji M

    2012-03-13

    To explain eyespot colour-pattern determination in butterfly wings, the induction model has been discussed based on colour-pattern analyses of various butterfly eyespots. However, a detailed structural analysis of eyespots that can serve as a foundation for future studies is still lacking. In this study, fundamental structural rules related to butterfly eyespots are proposed, and the induction model is elaborated in terms of the possible dynamics of morphogenic signals involved in the development of eyespots and parafocal elements (PFEs) based on colour-pattern analysis of the nymphalid butterfly Junonia almana. In a well-developed eyespot, the inner black core ring is much wider than the outer black ring; this is termed the inside-wide rule. It appears that signals are wider near the focus of the eyespot and become narrower as they expand. Although fundamental signal dynamics are likely to be based on a reaction-diffusion mechanism, they were described well mathematically as a type of simple uniformly decelerated motion in which signals associated with the outer and inner black rings of eyespots and PFEs are released at different time points, durations, intervals, and initial velocities into a two-dimensional field of fundamentally uniform or graded resistance; this produces eyespots and PFEs that are diverse in size and structure. The inside-wide rule, eyespot distortion, structural differences between small and large eyespots, and structural changes in eyespots and PFEs in response to physiological treatments were explained well using mathematical simulations. Natural colour patterns and previous experimental findings that are not easily explained by the conventional gradient model were also explained reasonably well by the formal mathematical simulations performed in this study. In a mode free from speculative molecular interactions, the present study clarifies fundamental structural rules related to butterfly eyespots, delineates a theoretical basis for the

  12. Biomechanics of the Peacock's Display: How Feather Structure and Resonance Influence Multimodal Signaling.

    Directory of Open Access Journals (Sweden)

    Roslyn Dakin

    Full Text Available Courtship displays may serve as signals of the quality of motor performance, but little is known about the underlying biomechanics that determines both their signal content and costs. Peacocks (Pavo cristatus perform a complex, multimodal "train-rattling" display in which they court females by vibrating the iridescent feathers in their elaborate train ornament. Here we study how feather biomechanics influences the performance of this display using a combination of field recordings and laboratory experiments. Using high-speed video, we find that train-rattling peacocks stridulate their tail feathers against the train at 25.6 Hz, on average, generating a broadband, pulsating mechanical sound at that frequency. Laboratory measurements demonstrate that arrays of peacock tail and train feathers have a broad resonant peak in their vibrational spectra at the range of frequencies used for train-rattling during the display, and the motion of feathers is just as expected for feathers shaking near resonance. This indicates that peacocks are able to drive feather vibrations energetically efficiently over a relatively broad range of frequencies, enabling them to modulate the feather vibration frequency of their displays. Using our field data, we show that peacocks with longer trains use slightly higher vibration frequencies on average, even though longer train feathers are heavier and have lower resonant frequencies. Based on these results, we propose hypotheses for future studies of the function and energetics of this display that ask why its dynamic elements might attract and maintain female attention. Finally, we demonstrate how the mechanical structure of the train feathers affects the peacock's visual display by allowing the colorful iridescent eyespots-which strongly influence female mate choice-to remain nearly stationary against a dynamic iridescent background.

  13. Biomechanics of the Peacock's Display: How Feather Structure and Resonance Influence Multimodal Signaling.

    Science.gov (United States)

    Dakin, Roslyn; McCrossan, Owen; Hare, James F; Montgomerie, Robert; Amador Kane, Suzanne

    2016-01-01

    Courtship displays may serve as signals of the quality of motor performance, but little is known about the underlying biomechanics that determines both their signal content and costs. Peacocks (Pavo cristatus) perform a complex, multimodal "train-rattling" display in which they court females by vibrating the iridescent feathers in their elaborate train ornament. Here we study how feather biomechanics influences the performance of this display using a combination of field recordings and laboratory experiments. Using high-speed video, we find that train-rattling peacocks stridulate their tail feathers against the train at 25.6 Hz, on average, generating a broadband, pulsating mechanical sound at that frequency. Laboratory measurements demonstrate that arrays of peacock tail and train feathers have a broad resonant peak in their vibrational spectra at the range of frequencies used for train-rattling during the display, and the motion of feathers is just as expected for feathers shaking near resonance. This indicates that peacocks are able to drive feather vibrations energetically efficiently over a relatively broad range of frequencies, enabling them to modulate the feather vibration frequency of their displays. Using our field data, we show that peacocks with longer trains use slightly higher vibration frequencies on average, even though longer train feathers are heavier and have lower resonant frequencies. Based on these results, we propose hypotheses for future studies of the function and energetics of this display that ask why its dynamic elements might attract and maintain female attention. Finally, we demonstrate how the mechanical structure of the train feathers affects the peacock's visual display by allowing the colorful iridescent eyespots-which strongly influence female mate choice-to remain nearly stationary against a dynamic iridescent background.

  14. Integration of wings and their eyespots in the speckled wood butterfly Pararge aegeria.

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    Breuker, Casper J; Gibbs, Melanie; Van Dyck, Hans; Brakefield, Paul M; Klingenberg, Christian Peter; Van Dongen, Stefan

    2007-07-15

    We investigated both the phenotypic and developmental integration of eyespots on the fore- and hindwings of speckled wood butterflies Pararge aegeria. Eyespots develop within a framework of wing veins, which may not only separate eyespots developmentally, but may at the same time also integrate them by virtue of being both signalling sources and barriers during eyespot development. We therefore specifically investigated the interaction between wing venation patterns and eyespot integration. Phenotypic covariation among eyespots was very high, but only eyespots in neighbouring wing cells and in homologous wing cells on different wing surfaces were developmentally integrated. This can be explained by the fact that the wing cells of these eyespots share one or more wing veins. The wing venation patterns of fore- and hindwings were highly integrated, both phenotypically and developmentally. This did not affect overall developmental integration of the eyespots. The adaptive significance of integration patterns is discussed and more specifically we stress the need to conduct studies on phenotypic plasticity of integration.

  15. The morphogenesis of feathers.

    Science.gov (United States)

    Yu, Mingke; Wu, Ping; Widelitz, Randall B; Chuong, Cheng-Ming

    2002-11-21

    Feathers are highly ordered, hierarchical branched structures that confer birds with the ability of flight. Discoveries of fossilized dinosaurs in China bearing 'feather-like' structures have prompted interest in the origin and evolution of feathers. However, there is uncertainty about whether the irregularly branched integumentary fibres on dinosaurs such as Sinornithosaurus are truly feathers, and whether an integumentary appendage with a major central shaft and notched edges is a non-avian feather or a proto-feather. Here, we use a developmental approach to analyse molecular mechanisms in feather-branching morphogenesis. We have used the replication-competent avian sarcoma retrovirus to deliver exogenous genes to regenerating flight feather follicles of chickens. We show that the antagonistic balance between noggin and bone morphogenetic protein 4 (BMP4) has a critical role in feather branching, with BMP4 promoting rachis formation and barb fusion, and noggin enhancing rachis and barb branching. Furthermore, we show that sonic hedgehog (Shh) is essential for inducing apoptosis of the marginal plate epithelia, which results in spaces between barbs. Our analyses identify the molecular pathways underlying the topological transformation of feathers from cylindrical epithelia to the hierarchical branched structures, and provide insights on the possible developmental mechanisms in the evolution of feather forms.

  16. Relative feather mass indices: are feather masses needed to ...

    African Journals Online (AJOL)

    Relative feather mass indices: are feather masses needed to estimate the percentage of new feather mass grown for moult regression models? ... As an alternative, it is here tested if feather mass indices may be sufficient replacements for species-specific feather masses. Thirty-five species of birds with known primary ...

  17. Differential involvement of Hedgehog signaling in butterfly wing and eyespot development.

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    Tong, Xiaoling; Lindemann, Anna; Monteiro, Antónia

    2012-01-01

    Butterfly eyespots may have evolved from the recruitment of pre-existent gene circuits or regulatory networks into novel locations on the wing. Gene expression data suggests one such circuit, the Hedgehog (Hh) signaling pathway and its target gene engrailed (en), was recruited from a role in patterning the anterior-posterior insect wing axis to a role patterning butterfly eyespots. However, while Junonia coenia expresses hh and en both in the posterior compartment of the wing and in eyespot centers, Bicyclus anynana lacks hh eyespot-specific expression. This suggests that Hh signaling may not be functioning in eyespot development in either species or that it functions in J. coenia but not in B. anynana. In order to test these hypotheses, we performed functional tests of Hh signaling in these species. We investigated the effects of Hh protein sequestration during the larval stage on en expression levels, and on wing size and eyespot size in adults. Hh sequestration led to significantly reduced en expression and to significantly smaller wings and eyespots in both species. But while eyespot size in B. anynana was reduced proportionately to wing size, in J. coenia, eyespots were reduced disproportionately, indicating an independent role of Hh signaling in eyespot development in J. coenia. We conclude that while Hh signaling retains a conserved role in promoting wing growth across nymphalid butterflies, it plays an additional role in eyespot development in some, but not all, lineages of nymphalid butterflies. We discuss our findings in the context of alternative evolutionary scenarios that led to the differential expression of hh and other Hh pathway signaling members across nymphalid species.

  18. Differential involvement of Hedgehog signaling in butterfly wing and eyespot development.

    Directory of Open Access Journals (Sweden)

    Xiaoling Tong

    Full Text Available Butterfly eyespots may have evolved from the recruitment of pre-existent gene circuits or regulatory networks into novel locations on the wing. Gene expression data suggests one such circuit, the Hedgehog (Hh signaling pathway and its target gene engrailed (en, was recruited from a role in patterning the anterior-posterior insect wing axis to a role patterning butterfly eyespots. However, while Junonia coenia expresses hh and en both in the posterior compartment of the wing and in eyespot centers, Bicyclus anynana lacks hh eyespot-specific expression. This suggests that Hh signaling may not be functioning in eyespot development in either species or that it functions in J. coenia but not in B. anynana. In order to test these hypotheses, we performed functional tests of Hh signaling in these species. We investigated the effects of Hh protein sequestration during the larval stage on en expression levels, and on wing size and eyespot size in adults. Hh sequestration led to significantly reduced en expression and to significantly smaller wings and eyespots in both species. But while eyespot size in B. anynana was reduced proportionately to wing size, in J. coenia, eyespots were reduced disproportionately, indicating an independent role of Hh signaling in eyespot development in J. coenia. We conclude that while Hh signaling retains a conserved role in promoting wing growth across nymphalid butterflies, it plays an additional role in eyespot development in some, but not all, lineages of nymphalid butterflies. We discuss our findings in the context of alternative evolutionary scenarios that led to the differential expression of hh and other Hh pathway signaling members across nymphalid species.

  19. Temporal gene expression variation associated with eyespot size plasticity in Bicyclus anynana.

    Directory of Open Access Journals (Sweden)

    Jeffrey C Oliver

    Full Text Available Seasonal polyphenism demonstrates an organism's ability to respond to predictable environmental variation with alternative phenotypes, each presumably better suited to its respective environment. However, the molecular mechanisms linking environmental variation to alternative phenotypes via shifts in development remain relatively unknown. Here we investigate temporal gene expression variation in the seasonally polyphenic butterfly Bicyclus anynana. This species shows drastic changes in eyespot size depending on the temperature experienced during larval development. The wet season form (larvae reared over 24°C has large ventral wing eyespots while the dry season form (larvae reared under 19°C has much smaller eyespots. We compared the expression of three proteins, Notch, Engrailed, and Distal-less, in the future eyespot centers of the two forms to determine if eyespot size variation is associated with heterochronic shifts in the onset of their expression. For two of these proteins, Notch and Engrailed, expression in eyespot centers occurred earlier in dry season than in wet season larvae, while Distal-less showed no temporal difference between the two forms. These results suggest that differences between dry and wet season adult wings could be due to a delay in the onset of expression of these eyespot-associated genes. Early in eyespot development, Notch and Engrailed may be functioning as repressors rather than activators of the eyespot gene network. Alternatively, temporal variation in the onset of early expressed genes between forms may have no functional consequences to eyespot size regulation and may indicate the presence of an 'hourglass' model of development in butterfly eyespots.

  20. A Model for Selection of Eyespots on Butterfly Wings.

    Science.gov (United States)

    Sekimura, Toshio; Venkataraman, Chandrasekhar; Madzvamuse, Anotida

    2015-01-01

    The development of eyespots on the wing surface of butterflies of the family Nympalidae is one of the most studied examples of biological pattern formation.However, little is known about the mechanism that determines the number and precise locations of eyespots on the wing. Eyespots develop around signaling centers, called foci, that are located equidistant from wing veins along the midline of a wing cell (an area bounded by veins). A fundamental question that remains unsolved is, why a certain wing cell develops an eyespot, while other wing cells do not. We illustrate that the key to understanding focus point selection may be in the venation system of the wing disc. Our main hypothesis is that changes in morphogen concentration along the proximal boundary veins of wing cells govern focus point selection. Based on previous studies, we focus on a spatially two-dimensional reaction-diffusion system model posed in the interior of each wing cell that describes the formation of focus points. Using finite element based numerical simulations, we demonstrate that variation in the proximal boundary condition is sufficient to robustly select whether an eyespot focus point forms in otherwise identical wing cells. We also illustrate that this behavior is robust to small perturbations in the parameters and geometry and moderate levels of noise. Hence, we suggest that an anterior-posterior pattern of morphogen concentration along the proximal vein may be the main determinant of the distribution of focus points on the wing surface. In order to complete our model, we propose a two stage reaction-diffusion system model, in which an one-dimensional surface reaction-diffusion system, posed on the proximal vein, generates the morphogen concentrations that act as non-homogeneous Dirichlet (i.e., fixed) boundary conditions for the two-dimensional reaction-diffusion model posed in the wing cells. The two-stage model appears capable of generating focus point distributions observed in

  1. A Model for Selection of Eyespots on Butterfly Wings.

    Directory of Open Access Journals (Sweden)

    Toshio Sekimura

    Full Text Available The development of eyespots on the wing surface of butterflies of the family Nympalidae is one of the most studied examples of biological pattern formation.However, little is known about the mechanism that determines the number and precise locations of eyespots on the wing. Eyespots develop around signaling centers, called foci, that are located equidistant from wing veins along the midline of a wing cell (an area bounded by veins. A fundamental question that remains unsolved is, why a certain wing cell develops an eyespot, while other wing cells do not.We illustrate that the key to understanding focus point selection may be in the venation system of the wing disc. Our main hypothesis is that changes in morphogen concentration along the proximal boundary veins of wing cells govern focus point selection. Based on previous studies, we focus on a spatially two-dimensional reaction-diffusion system model posed in the interior of each wing cell that describes the formation of focus points. Using finite element based numerical simulations, we demonstrate that variation in the proximal boundary condition is sufficient to robustly select whether an eyespot focus point forms in otherwise identical wing cells. We also illustrate that this behavior is robust to small perturbations in the parameters and geometry and moderate levels of noise. Hence, we suggest that an anterior-posterior pattern of morphogen concentration along the proximal vein may be the main determinant of the distribution of focus points on the wing surface. In order to complete our model, we propose a two stage reaction-diffusion system model, in which an one-dimensional surface reaction-diffusion system, posed on the proximal vein, generates the morphogen concentrations that act as non-homogeneous Dirichlet (i.e., fixed boundary conditions for the two-dimensional reaction-diffusion model posed in the wing cells. The two-stage model appears capable of generating focus point distributions

  2. Unzipping bird feathers.

    Science.gov (United States)

    Kovalev, Alexander; Filippov, Alexander E; Gorb, Stanislav N

    2014-03-06

    The bird feather vane can be separated into two parts by pulling the barbs apart. The original state can be re-established easily by lightly stroking through the feather. Hooklets responsible for holding vane barbs together are not damaged by multiple zipping and unzipping cycles. Because numerous microhooks keep the integrity of the feather, their properties are of great interest for understanding mechanics of the entire feather structure. This study was undertaken to estimate the separation force of single hooklets and their arrays using force measurement of an unzipping feather vane. The hooklets usually separate in some number synchronously (20 on average) with the highest observed separation force of 1.74 mN (average force 0.27 mN), whereas the single hooklet separation force was 14 μN. A simple numerical model was suggested for a better understanding of zipping and unzipping behaviour in feathers. The model demonstrates features similar to those observed in experiments.

  3. Eyespots deflect predator attack increasing fitness and promoting the evolution of phenotypic plasticity

    Science.gov (United States)

    Prudic, Kathleen L.; Stoehr, Andrew M.; Wasik, Bethany R.; Monteiro, Antónia

    2015-01-01

    Some eyespots are thought to deflect attack away from the vulnerable body, yet there is limited empirical evidence for this function and its adaptive advantage. Here, we demonstrate the conspicuous ventral hindwing eyespots found on Bicyclus anynana butterflies protect against invertebrate predators, specifically praying mantids. Wet season (WS) butterflies with larger, brighter eyespots were easier for mantids to detect, but more difficult to capture compared to dry season (DS) butterflies with small, dull eyespots. Mantids attacked the wing eyespots of WS butterflies more frequently resulting in greater butterfly survival and reproductive success. With a reciprocal eyespot transplant, we demonstrated the fitness benefits of eyespots were independent of butterfly behaviour. Regardless of whether the butterfly was WS or DS, large marginal eyespots pasted on the hindwings increased butterfly survival and successful oviposition during predation encounters. In previous studies, DS B. anynana experienced delayed detection by vertebrate predators, but both forms suffered low survival once detected. Our results suggest predator abundance, identity and phenology may all be important selective forces for B. anynana. Thus, reciprocal selection between invertebrate and vertebrate predators across seasons may contribute to the evolution of the B. anynana polyphenism. PMID:25392465

  4. Wound healing, calcium signaling, and other novel pathways are associated with the formation of butterfly eyespots.

    Science.gov (United States)

    Özsu, Nesibe; Monteiro, Antónia

    2017-10-16

    One hypothesis surrounding the origin of novel traits is that they originate from the co-option of pre-existing genes or larger gene regulatory networks into novel developmental contexts. Insights into a trait's evolutionary origins can, thus, be gained via identification of the genes underlying trait development, and exploring whether those genes also function in other developmental contexts. Here we investigate the set of genes associated with the development of eyespot color patterns, a trait that originated once within the Nymphalid family of butterflies. Although several genes associated with eyespot development have been identified, the eyespot gene regulatory network remains largely unknown. In this study, next-generation sequencing and transcriptome analyses were used to identify a large set of genes associated with eyespot development of Bicyclus anynana butterflies, at 3-6 h after pupation, prior to the differentiation of the color rings. Eyespot-associated genes were identified by comparing the transcriptomes of homologous micro-dissected wing tissues that either develop or do not develop eyespots in wild-type and a mutant line of butterflies, Spotty, with extra eyespots. Overall, 186 genes were significantly up and down-regulated in wing tissues that develop eyespots compared to wing tissues that do not. Many of the differentially expressed genes have yet to be annotated. New signaling pathways, including the Toll, Fibroblast Growth Factor (FGF), extracellular signal-regulated kinase (ERK) and/or Jun N-terminal kinase (JNK) signaling pathways are associated for the first time with eyespot development. In addition, several genes involved in wound healing and calcium signaling were also found to be associated with eyespots. Overall, this study provides the identity of many new genes and signaling pathways associated with eyespots, and suggests that the ancient wound healing gene regulatory network may have been co-opted to cells at the center of the

  5. Butterfly Eyespots: Their Potential Influence on Aesthetic Preferences and Conservation Attitudes.

    Science.gov (United States)

    Manesi, Zoi; Van Lange, Paul A M; Pollet, Thomas V

    2015-01-01

    Research has shown that the mere presence of stimuli that resemble eyes is sufficient to attract attention, elicit aesthetic responses, and can even enhance prosocial behavior. However, it is less clear whether eye-like stimuli could also be used as a tool for nature conservation. Several animal species, including butterflies, develop eye-like markings that are known as eyespots. In the present research, we explored whether the mere display of eyespots on butterfly wings can enhance: (a) liking for a butterfly species, and (b) attitudes and behaviors towards conservation of a butterfly species. Four online experimental studies, involving 613 participants, demonstrated that eyespots significantly increased liking for a butterfly species. Furthermore, eyespots significantly increased positive attitudes towards conservation of a butterfly species (Studies 1, 2 and 4), whereas liking mediated the eyespot effect on conservation attitudes (Study 2). However, we also found some mixed evidence for an association between eyespots and actual conservation behavior (Studies 3 and 4). Overall, these findings suggest that eyespots may increase liking for an animal and sensitize humans to conservation. We discuss possible implications for biodiversity conservation and future research directions.

  6. Butterfly Eyespots: Their Potential Influence on Aesthetic Preferences and Conservation Attitudes.

    Directory of Open Access Journals (Sweden)

    Zoi Manesi

    Full Text Available Research has shown that the mere presence of stimuli that resemble eyes is sufficient to attract attention, elicit aesthetic responses, and can even enhance prosocial behavior. However, it is less clear whether eye-like stimuli could also be used as a tool for nature conservation. Several animal species, including butterflies, develop eye-like markings that are known as eyespots. In the present research, we explored whether the mere display of eyespots on butterfly wings can enhance: (a liking for a butterfly species, and (b attitudes and behaviors towards conservation of a butterfly species. Four online experimental studies, involving 613 participants, demonstrated that eyespots significantly increased liking for a butterfly species. Furthermore, eyespots significantly increased positive attitudes towards conservation of a butterfly species (Studies 1, 2 and 4, whereas liking mediated the eyespot effect on conservation attitudes (Study 2. However, we also found some mixed evidence for an association between eyespots and actual conservation behavior (Studies 3 and 4. Overall, these findings suggest that eyespots may increase liking for an animal and sensitize humans to conservation. We discuss possible implications for biodiversity conservation and future research directions.

  7. Butterfly Eyespots: Their Potential Influence on Aesthetic Preferences and Conservation Attitudes

    Science.gov (United States)

    Manesi, Zoi; Van Lange, Paul A. M.; Pollet, Thomas V.

    2015-01-01

    Research has shown that the mere presence of stimuli that resemble eyes is sufficient to attract attention, elicit aesthetic responses, and can even enhance prosocial behavior. However, it is less clear whether eye-like stimuli could also be used as a tool for nature conservation. Several animal species, including butterflies, develop eye-like markings that are known as eyespots. In the present research, we explored whether the mere display of eyespots on butterfly wings can enhance: (a) liking for a butterfly species, and (b) attitudes and behaviors towards conservation of a butterfly species. Four online experimental studies, involving 613 participants, demonstrated that eyespots significantly increased liking for a butterfly species. Furthermore, eyespots significantly increased positive attitudes towards conservation of a butterfly species (Studies 1, 2 and 4), whereas liking mediated the eyespot effect on conservation attitudes (Study 2). However, we also found some mixed evidence for an association between eyespots and actual conservation behavior (Studies 3 and 4). Overall, these findings suggest that eyespots may increase liking for an animal and sensitize humans to conservation. We discuss possible implications for biodiversity conservation and future research directions. PMID:26544692

  8. A simulation study of mutations in the genetic regulatory hierarchy for butterfly eyespot focus determination.

    Science.gov (United States)

    Marcus, Jeffrey M; Evans, Travis M

    2008-09-01

    The color patterns on the wings of butterflies have been an important model system in evolutionary developmental biology. A recent computational model tested genetic regulatory hierarchies hypothesized to underlie the formation of butterfly eyespot foci [Evans, T.M., Marcus, J.M., 2006. A simulation study of the genetic regulatory hierarchy for butterfly eyespot focus determination. Evol. Dev. 8, 273-283]. The computational model demonstrated that one proposed hierarchy was incapable of reproducing the known patterns of gene expression associated with eyespot focus determination in wild-type butterflies, but that two slightly modified alternative hierarchies were capable of reproducing all of the known gene expressions patterns. Here we extend the computational models previously implemented in Delphi 2.0 to two mutants derived from the squinting bush brown butterfly (Bicyclus anynana). These two mutants, comet and Cyclops, have aberrantly shaped eyespot foci that are produced by different mechanisms. The comet mutation appears to produce a modified interaction between the wing margin and the eyespot focus that results in a series of comet-shaped eyespot foci. The Cyclops mutation causes the failure of wing vein formation between two adjacent wing-cells and the fusion of two adjacent eyespot foci to form a single large elongated focus in their place. The computational approach to modeling pattern formation in these mutants allows us to make predictions about patterns of gene expression, which are largely unstudied in butterfly mutants. It also suggests a critical experiment that will allow us to distinguish between two hypothesized genetic regulatory hierarchies that may underlie all butterfly eyespot foci.

  9. A Simulation Study of Mutations in the Genetic Regulatory Hierarchy for Butterfly Eyespot Focus Determination

    OpenAIRE

    Marcus, Jeffrey M.; Evans, Travis M.

    2008-01-01

    The color patterns on the wings of butterflies have been an important model system in evolutionary developmental biology. A recent computational model tested genetic regulatory hierarchies hypothesized to underlie the formation of butterfly eyespot foci (Evans and Marcus, 2006). The computational model demonstrated that one proposed hierarchy was incapable of reproducing the known patterns of gene expression associated with eyespot focus determination in wild-type butterflies, but that two sl...

  10. The morphology of neoptile feathers: ancestral state reconstruction and its phylogenetic implications.

    Science.gov (United States)

    Foth, Christian

    2011-04-01

    Avian neoptile feathers are defined as the first feather generation, which covers the chick after hatching, and usually described as simple structures consisting of numerous downy barbs which are radially symmetrically arranged and come together in a short calamus. In contrast, in some birds (e.g., Anas platyrhynchos, Dromaius novaehollandiae) the neoptile feathers have a prominent rhachis, and therefore display clear bilateral symmetry. Because the symmetrical variety found in neoptile feathers is poorly understood, their morphology was studied in a more comprehensive and phylogenetic approach. Neoptile body feathers from over 22 bird species were investigated using light microscopy, SEM, and MicroCT. Characters such as an anterior-posterior axis, a central rhachis, medullary cells, and structure of the calamus wall were defined and mapped onto recent phylogenetic hypotheses for extant birds. It can be shown that bilaterally symmetric neoptile feathers (with a solid calamus wall) were already present in the stem lineage of crown-group birds (Neornithes). In contrast, simple radially symmetric neoptile feathers (with a fragile calamus wall) are an apomorphic character complex for the clade Neoaves. The simple morphology of this feather type may be the result of a reduced period of development during embryogenesis. To date, embryogenesis of neoptile feathers from only a few bird species was used as a model to reconstruct feather evolution. Because this study shows that the morphology of neoptile feathers is more diverse and even shows a clear phylogenetic signal, it is necessary to expand the spectrum of "model organisms" to species with bilaterally symmetric neoptile feathers and compare differences in the frequency of feather development from a phylogenetic point of view. Copyright © 2011 Wiley-Liss, Inc.

  11. On the Morphogenesis of Feathers

    Science.gov (United States)

    Yu, Mingke; Wu, Ping; Widelitz, Randall B.; Chuong, Cheng-Ming

    2015-01-01

    The most unique character of the feather is its highly ordered hierarchical branched structure1, 2. This evolutionary novelty confers flight function to birds3–5. Recent discoveries of fossils in China have prompted keen interest in the origin and evolution of feathers6–14. However, controversy arises whether the irregularly branched integumentary fibers on dinosaurs such as Sinornithosaurus are truly feathers6, 11, and whether an integumentary appendage with a major central shaft and notched edges is a non-avian feather or a proto-feather8–10. Here we take a developmental approach to analyze molecular mechanisms in feather branching morphogenesis. We have used the replication competent avian sarcoma (RCAS) retrovirus15 to efficiently deliver exogenous genes to regenerating chicken flight feather follicles. We show that the antagonistic balance between noggin and bone morphogenetic protein 4 (BMP4) plays a critical role in feather branching, with BMP4 promoting rachis formation and barb fusion, and noggin enhancing rachis and barb branching. Furthermore we show that sonic hedgehog (SHH) is essential for apoptosis of the marginal plate epithelia to become spaces between barbs. Our analyses show the molecular pathways underlying the topological transformation of feathers from cylindrical epithelia to the hierarchical branched structures, and provide first clues on the possible developmental mechanisms in the evolution of feather forms. PMID:12442169

  12. Phylogenetics and ecomorphology of emarginate primary feathers.

    Science.gov (United States)

    Klaassen van Oorschot, Brett; Tang, Ho Kwan; Tobalske, Bret W

    2017-07-01

    Wing tip slots are a distinct morphological trait broadly expressed across the avian clade, but are generally perceived to be unique to soaring raptors. These slots are the result of emarginations on the distal leading and trailing edges of primary feathers, and allow the feathers to behave as individual airfoils. Research suggests these emarginate feathers are an adaptation to increase glide efficiency by mitigating induced drag in a manner similar to aircraft winglets. If so, we might expect birds known for gliding and soaring to exhibit emarginate feather morphology; however, that is not always the case. Here, we explore emargination across the avian clade, and examine associations between emargination and ecological and morphological variables. Pelagic birds exhibit pointed, high-aspect ratio wings without slots, whereas soaring terrestrial birds exhibit prominent wing-tip slots. Thus, we formed four hypotheses: (1) Emargination is segregated according to habitat (terrestrial, coastal/freshwater, pelagic). (2) Emargination is positively correlated with mass. (3) Emargination varies inversely with aspect ratio and directly with wing loading and disc loading. (4) Emargination varies according to flight style, foraging style, and diet. We found that emargination falls along a continuum that varies with habitat: Pelagic species tend to have zero emargination, coastal/freshwater birds have some emargination, and terrestrial species have a high degree of emargination. Among terrestrial and coastal/freshwater species, the degree of emargination is positively correlated with mass. We infer this may be the result of selection to mitigate induced power requirements during slow flight that otherwise scale adversely with increasing body size. Since induced power output is greatest during slow flight, we hypothesize that emargination may be an adaptation to assist vertical take-off and landing rather than glide efficiency as previously hypothesized. © 2017 Wiley

  13. Flight feather attachment in rock pigeons (Columba livia): covert feathers and smooth muscle coordinate a morphing wing.

    Science.gov (United States)

    Hieronymus, Tobin L

    2016-11-01

    Mechanisms for passively coordinating forelimb movements and flight feather abduction and adduction have been described separately from both in vivo and ex vivo studies. Skeletal coordination has been identified as a way for birds to simplify the neuromotor task of controlling flight stroke, but an understanding of the relationship between skeletal coordination and the coordination of the aerodynamic control surface (the flight feathers) has been slow to materialize. This break between the biomechanical and aerodynamic approaches - between skeletal kinematics and airfoil shape - has hindered the study of dynamic flight behaviors. Here I use dissection and histology to identify previously overlooked interconnections between musculoskeletal elements and flight feathers. Many of these structures are well-placed to directly link elements of the passive musculoskeletal coordination system with flight feather movements. Small bundles of smooth muscle form prominent connections between upper forearm coverts (deck feathers) and the ulna, as well as the majority of interconnections between major flight feathers of the hand. Abundant smooth muscle may play a role in efficient maintenance of folded wing posture, and may also provide an autonomically regulated means of tuning wing shape and aeroelastic behavior in flight. The pattern of muscular and ligamentous linkages of flight feathers to underlying muscle and bone may provide predictable passive guidance for the shape of the airfoil during flight stroke. The structures described here provide an anatomical touchstone for in vivo experimental tests of wing surface coordination in an extensively researched avian model species. © 2016 Anatomical Society.

  14. Impact of feathers and feather follicles on broiler carcass bacteria.

    Science.gov (United States)

    Cason, J A; Hinton, A; Buhr, R J

    2004-08-01

    Genetically featherless and feathered broiler siblings were used to test the contribution of feathers and feather follicles to the numbers of aerobic bacteria, Escherichia coli, and Campylobacter in whole-carcass rinse samples taken immediately after carcasses were defeathered for 30 or 60 s. Numbers of spoilage bacteria were counted after the same fully processed carcasses were stored for 1 wk at 2 degrees C. In each of 3 replications, twenty-eight 11-wk-old, mixed-sex, genetically featherless or feathered broilers were processed in a laboratory processing facility. Immediately after individual defeathering in a mechanical picker, carcasses were sampled using a carcass rinse technique. Carcasses were eviscerated, immersion chilled at 2 degrees C for 30 min, individually bagged, and stored for 1 wk at 2 degrees C, after which all carcasses were rinsed again, and spoilage bacteria in the rinsate were enumerated. There were no significant differences (P defeathering and no differences between carcasses picked for 30 or 60 s. There were no differences in numbers of spoilage bacteria after 1 wk of refrigeration for any of the feather presence-picking length combinations. Although the defeathering step in poultry processing has been identified as an opportunity for bacterial contamination from the intestinal tract and cross-contamination between carcasses, the presence of feathers and feather follicles does not make a significant difference in carcass bacterial contamination immediately after defeathering or in spoilage bacteria after 1 wk of refrigeration.

  15. Light diffraction through a feather

    Directory of Open Access Journals (Sweden)

    Pérez García, Hugo;

    2012-01-01

    Full Text Available We have used a feather to study light diffraction, in a qualitative as well as in a quantitative manner. Experimental measurement of the separation between the bright spots obtained with a laser pointer allowed the determination of the space between feather's barbs and barbules. The results we have obtained agree satisfactorily with those corresponding to a typical feather. Due to the kind of materials, the related concepts and the experimental results, this activity becomes an excellent didactic resource suitable for studying diffraction, both in introductory undergraduate as well as in secondary school physics courses.

  16. Colour pattern homology and evolution in Vanessa butterflies (Nymphalidae: Nymphalini): eyespot characters.

    Science.gov (United States)

    Abbasi, R; Marcus, J M

    2015-11-01

    Ocelli are serially repeated colour patterns on the wings of many butterflies. Eyespots are elaborate ocelli that function in predator avoidance and deterrence as well as in mate choice. A phylogenetic approach was used to study ocelli and eyespot evolution in Vanessa butterflies, a genus exhibiting diverse phenotypes among these serial homologs. Forty-four morphological characters based on eyespot number, arrangement, shape and the number of elements in each eyespot were defined and scored. Ocelli from eight wing cells on the dorsal and ventral surfaces of the forewing and hindwing were evaluated. The evolution of these characters was traced over a phylogeny of Vanessa based on 7750 DNA base pairs from 10 genes. Our reconstruction predicts that the ancestral Vanessa had 5 serially arranged ocelli on all four wing surfaces. The ancestral state on the dorsal forewing and ventral hindwing was ocelli arranged in two heterogeneous groups. On the dorsal hindwing, the ancestral state was either homogenous or ocelli arranged in two heterogeneous groups. On the ventral forewing, we determined that the ancestral state was organized into three heterogeneous groups. In Vanessa, almost all ocelli are individuated and capable of independent evolution relative to other colour patterns except for the ocelli in cells -1 and 0 on the dorsal and ventral forewings, which appear to be constrained to evolve in parallel. The genus Vanessa is a good model system for the study of serial homology and the interaction of selective forces with developmental architecture to produce diversity in butterfly colour patterns. © 2015 European Society For Evolutionary Biology. Journal of Evolutionary Biology © 2015 European Society For Evolutionary Biology.

  17. Bioplastics from feather quill.

    Science.gov (United States)

    Ullah, Aman; Vasanthan, Thavaratnam; Bressler, David; Elias, Anastasia L; Wu, Jianping

    2011-10-10

    Poultry feather quills have been extruded in a twin screw extruder with sodium sulfite treatment as a reducing agent. The effect of four different plasticizers (ethylene glycol, propylene glycol, glycerol, and diethyl tartrate) on the thermoplastic properties was then investigated. Conformational changes and plasticizer-protein interactions in the extruded resins were assessed by Fourier transform infrared spectroscopy (FTIR), while viscoelastic behavior of the quill keratin plasticized with different plasticizers was investigated by dynamic mechanical analysis (DMA). Differential scanning calorimetry (DSC) was used to determine the effect of different plasticizers on protein denaturation. Thermal degradation patterns of the extrudates were studied by thermogravimetric analysis (TGA). The effect of plasticizers on the mechanical properties of resins was also assessed by tensile strength measurements. Results indicated that ethylene glycol was able to interact more effectively with quill keratin at the molecular level, exhibiting only one sharp glass transition, better mechanical properties, and higher transparency compared to other plasticized resins. The two phases found in glycerol plasticized material were attributed to glycerol-rich and protein-rich zones. Propylene glycol and diethyl tartrate exhibited lower H-bonding interactions and showed wide transition regions in DMA profiles during heating, suggesting weak and heterogeneous interactions between quill keratin and these plasticizers.

  18. Brandburg Prominance, Namibia, Africa

    Science.gov (United States)

    1993-01-01

    The Brandburg Prominance, Namibia (21.0S, 14.5E) is a round basaltic plug and is the highest feature (over 8,000 ft) in the country. Wind streaks on the surface of the coastal desert, aligned northeast to southwest, are the result of frequent sand storms. Coastal stratus clouds provide most of the life supporting moisture as fog droplets in this arid land where annual rainfall may be less than a quarter of an inch for decades at a time.

  19. Feather corticosterone reveals developmental stress in seabirds.

    Science.gov (United States)

    Will, Alexis P; Suzuki, Yuya; Elliott, Kyle H; Hatch, Scott A; Watanuki, Yutaka; Kitaysky, Alexander S

    2014-07-01

    In nest-bound avian offspring, food shortages typically trigger a release of the stress hormone corticosterone (CORT). Recent studies indicate that CORT is passively deposited in the tissue of growing feathers and thus may provide an integrated measure of stress incurred during development in the nest. The current hypothesis predicts that, assuming a constant rate of feather growth, elevated CORT circulating in the blood corresponds to higher levels of CORT in feather tissue, but experimental evidence for nutritionally stressed chicks is lacking. Here, we examined how food limitation affects feather CORT content in the rhinoceros auklet (Cerorhinca moncerata). We (i) used captive chicks reared on control versus restricted diets, and (ii) applied this technique to free-living chicks with unknown nutritional histories that fledged at three separate colonies. We found that (i) feather growth was not affected by experimentally induced nutritional stress; (ii) captive chicks raised on a restricted diet had higher levels of CORT in their primary feathers; (iii) feather CORT deposition is a sensitive method of detecting nutritional stress; and (iv) free-living fledglings from the colony with poor reproductive performance had higher CORT in their primary feathers. We conclude that feather CORT is a sensitive integrated measure revealing the temporal dynamics of food limitations experienced by rhinoceros auklet nestlings. The use of feather CORT may be a powerful endocrine tool in ecological and evolutionary studies of bird species with similar preferential allocation of limited resources to feather development. © 2014. Published by The Company of Biologists Ltd.

  20. Formation and support of prominence

    International Nuclear Information System (INIS)

    Forbes, T.G.

    1986-01-01

    A short introduction is given to the concepts discussed by the group on the formation and support of prominences. Only quiescent and long-lived active region prominences were considered, since transient prominence phenomena, such as sprays, surges, H alpha flare-loops, and coronal rain, are dynamically distinct from long-lived, prominences. Stable prominences (which are often referred to as filaments when seen against the disk) can be subdivided into three categories, namely active region prominences, quiescent prominences and polar crown prominences. The third category is closely related to the second since a quiescent prominence will eventually evolve into a polar crown prominence if it lasts long enough. The distinction between the first and second categories is not sharp either since intermediates exist here as well (Martin, 1973)

  1. Overexpression of TiERF1 enhances resistance to sharp eyespot in transgenic wheat

    OpenAIRE

    Chen, Liang; Zhang, ZengYan; Liang, HongXia; Liu, HongXia; Du, LiPu; Xu, Huijun; Xin, Zhiyong

    2008-01-01

    Wheat sharp eyespot, primarily caused by a soil-borne fungus Rhizoctonia cerealis, has become one of the most serious diseases of wheat in China. In this study, an ethylene response factor (ERF) gene from a wheat relative Thinopyrum intermedium, TiERF1, was characterized further, transgenic wheat lines expressing TiERF1 were developed, and the resistance of the transgenic wheat lines against R. cerealis was investigated. Southern blotting analysis indicated that at least two copies of the TiE...

  2. Do uric acid deposits in zooxanthellae function as eye-spots?

    Directory of Open Access Journals (Sweden)

    Hiroshi Yamashita

    2009-07-01

    Full Text Available The symbiosis between zooxanthellae (dinoflagellate genus Symbiodinium and corals is a fundamental basis of tropical marine ecosystems. However the physiological interactions of the hosts and symbionts are poorly understood. Recently, intracellular crystalline deposits in Symbiodinium were revealed to be uric acid functioning for nutrient storage. This is the first exploration of these enigmatic crystalline materials that had previously been misidentified as oxalic acid, providing new insights into the nutritional strategies of Symbiodinium in oligotrophic tropical waters. However, we believe these deposits also function as eye-spots on the basis of light and electron microscopic observations of motile cells of cultured Symbiodinium. The cells possessed crystalline deposit clusters in rows with each row 100-150 nm thick corresponding to 1/4 the wavelength of light and making them suitable for maximum wave interference and reflection of light. Crystalline clusters in cells observed with a light microscope strongly refracted and polarized light, and reflected or absorbed short wavelength light. The facts that purines, including uric acid, have been identified as the main constituents of light reflectors in many organisms, and that the photoreceptor protein, opsin, was detected in our Symbiodinium strain, support the idea that uric acid deposits in Symbiodinium motile cells may function as a component of an eye-spot.

  3. Do uric acid deposits in zooxanthellae function as eye-spots?

    Science.gov (United States)

    Yamashita, Hiroshi; Kobiyama, Atsushi; Koike, Kazuhiko

    2009-07-17

    The symbiosis between zooxanthellae (dinoflagellate genus Symbiodinium) and corals is a fundamental basis of tropical marine ecosystems. However the physiological interactions of the hosts and symbionts are poorly understood. Recently, intracellular crystalline deposits in Symbiodinium were revealed to be uric acid functioning for nutrient storage. This is the first exploration of these enigmatic crystalline materials that had previously been misidentified as oxalic acid, providing new insights into the nutritional strategies of Symbiodinium in oligotrophic tropical waters. However, we believe these deposits also function as eye-spots on the basis of light and electron microscopic observations of motile cells of cultured Symbiodinium. The cells possessed crystalline deposit clusters in rows with each row 100-150 nm thick corresponding to 1/4 the wavelength of light and making them suitable for maximum wave interference and reflection of light. Crystalline clusters in cells observed with a light microscope strongly refracted and polarized light, and reflected or absorbed short wavelength light. The facts that purines, including uric acid, have been identified as the main constituents of light reflectors in many organisms, and that the photoreceptor protein, opsin, was detected in our Symbiodinium strain, support the idea that uric acid deposits in Symbiodinium motile cells may function as a component of an eye-spot.

  4. Solar Features - Prominences and Filaments

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Prominences and filaments are two manifestations of the same phenomenon. Both prominences and filaments are features formed above the chromosphere by cool dense...

  5. A wheat cinnamyl alcohol dehydrogenase TaCAD12 contributes to host resistance to the sharp eyespot disease

    Directory of Open Access Journals (Sweden)

    Wei Rong

    2016-11-01

    Full Text Available Sharp eyespot, caused mainly by the necrotrophic fungus Rhizoctonia cerealis, is a destructive disease in hexaploid wheat (Triticum aestivum L.. In Arabidopsis, certain cinnamyl alcohol dehydrogenases (CADs have been implicated in monolignol biosynthesis and in defense response to bacterial pathogen infection. However, little is known about CADs in wheat defense responses to necrotrophic or soil-borne pathogens. In this study, we isolate a wheat CAD gene TaCAD12 in response to R. cerealis infection through microarray-based comparative transcriptomics, and study the enzyme activity and defense role of TaCAD12 in wheat. The transcriptional levels of TaCAD12 in sharp eyespot-resistant wheat lines were significantly higher compared with those in susceptible wheat lines. The sequence and phylogenetic analyses revealed that TaCAD12 belongs to IV group in CAD family. The biochemical assay proved that TaCAD12 protein is an authentic CAD enzyme and possesses catalytic efficiencies towards both coniferyl aldehyde and sinapyl aldehyde. Knock-down of TaCAD12 transcript significantly repressed resistance of the gene-silenced wheat plants to sharp eyespot caused by R. cerealis, whereas TaCAD12 overexpression markedly enhanced resistance of the transgenic wheat lines to sharp eyespot. Furthermore, certain defense genes (Defensin, PR10, PR17c, and Chitinase1 and monolignol biosynthesis-related genes (TaCAD1, TaCCR, and TaCOMT1 were up-regulated in the TaCAD12-overexpressing wheat plants but down-regulated in TaCAD12-silencing plants. These results suggest that TaCAD12 positively contributes to resistance against sharp eyespot through regulation of the expression of certain defense genes and monolignol biosynthesis-related genes in wheat.

  6. Applying chemical stimuli on feathers to reduce feather pecking in laying hens

    NARCIS (Netherlands)

    Harlander Matauschek, A.; Rodenburg, T.B.

    2011-01-01

    Recent studies have shown that spraying a distasteful substance (quinine) on a bird's feather cover reduced short-term feather pecking. The present experiment evaluated if other substances offer similar or better protection against feather pecking. One hundred and twenty birds were divided into 12

  7. New perspectives on solar prominences

    Science.gov (United States)

    Schmieder, B.; Aulanier, G.

    2012-06-01

    Recent observations of prominences obtained with high spatial and temporal resolution instruments, on board satellites (Hinode, SDO) as well as on the ground (SST) have provided very intriguing movies and open a new area for understanding the nature of prominences. The main topics are still debate: formation, dynamics, and characteristics of the plasma in the core and in the transition zone between the prominence and corona. We will review briefly the recent advances made in these topics, observationally as well as theoretically.

  8. The feeding habits of the eyespot skate Atlantoraja cyclophora (Elasmobranchii: Rajiformes in southeastern Brazil

    Directory of Open Access Journals (Sweden)

    Alessandra da Fonseca Viana

    2014-04-01

    Full Text Available The stomach contents of the eyespot skate, Atlantoraja cyclophora (Regan, 1903, were examined with the goal to provide information about the diet of the species. Samples were collected off the southern coast of Rio de Janeiro, Brazil, near Ilha Grande, between January 2006 and August 2007, at a depth of about 60 m. The diet was analyzed by sex, maturity stages and quarterly to verify differences in the importance of food items. The latter were analyzed by: frequency of occurrence, percentage of weight and in the Alimentary Index. The trophic niche width was determined to assess the degree of specialization in the diet. Additionally, the degree of dietary overlap between males and females; juveniles and adults and periods of the year were defined. A total of 59 individuals of A. cyclophora were captured. Females and adults were more abundant. The quarters with the highest concentrations of individuals were in the summer of the Southern Hemisphere: Jan-Feb-Mar 06 and Jan-Feb-Mar 07. Prey items were classed into five main groups: Crustacea, Teleosts, Elasmobranchs, Polychaeta, and Nematoda. The most important groups in the diet of the eyespot skate were Crustacea and Teleosts. The crab Achelous spinicarpus (Stimpson, 1871 was the most important item. The value of the niche width was small, indicating that a few food items are important. The comparison of the diet between males and females and juveniles and adults indicates a significant overlap between the sexes and stages of maturity; and according to quarters, the importance of prey groups differed (crustaceans were more important in the quarters of the summer and teleost in Jul-Aug-Sep and Oct-Nov-Dec 06, indicating seasonal differences in diet composition. Three groups with similar diets were formed in the cluster analysis: (Jan-Feb-Mar 06 and 07; (Apr-May-Jun 06 and Jul-Aug-Sep 07; (Jul-Aug-Sep 06 and Oct-Nov-Dec 06.

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

    Science.gov (United States)

    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.

  10. Structural coloration in a fossil feather.

    Science.gov (United States)

    Vinther, Jakob; Briggs, Derek E G; Clarke, Julia; Mayr, Gerald; Prum, Richard O

    2010-02-23

    Investigation of feathers from the famous Middle Eocene Messel Oil Shale near Darmstadt, Germany shows that they are preserved as arrays of fossilized melanosomes, the surrounding beta-keratin having degraded. The majority of feathers are preserved as aligned rod-shaped eumelanosomes. In some, however, the barbules of the open pennaceous, distal portion of the feather vane are preserved as a continuous external layer of closely packed melanosomes enclosing loosely aligned melanosomes. This arrangement is similar to the single thin-film nanostructure that generates an iridescent, structurally coloured sheen on the surface of black feathers in many lineages of living birds. This is, to our knowledge, the first evidence of preservation of a colour-producing nanostructure in a fossil feather and confirms the potential for determining colour differences in ancient birds and other dinosaurs.

  11. Are melanized feather barbs stronger?

    Science.gov (United States)

    Butler, Michael; Johnson, Amy S

    2004-01-01

    Melanin has been associated with increased resistance to abrasion, decreased wear and lowered barb breakage in feathers. But, this association was inferred without considering barb position along the rachis as a potentially confounding variable. We examined the cross-sectional area, breaking force, breaking stress, breaking strain and toughness of melanized and unmelanized barbs along the entire rachis of a primary feather from an osprey (Pandion haliaetus). Although breaking force was higher for melanized barbs, breaking stress (force divided by cross-sectional area) was greater for unmelanized barbs. But when position was considered, all mechanical differences between melanized and unmelanized barbs disappeared. Barb breaking stress, breaking strain and toughness decreased, and breaking stiffness increased, distally along the rachis. These proximal-distal material property changes are small and seem unlikely to affect flight performance of barbs. Our observations of barb bending, breaking and morphology, however, lead us to propose a design principle for barbs. We propose that, by being thicker-walled dorso-ventrally, the barb's flexural stiffness is increased during flight; but, by allowing for twisting when loaded with dangerously high forces, barbs firstly avoid failure by bending and secondly avoid complete failure by buckling rather than rupturing.

  12. Kingfisher feathers - colouration by pigments, spongy nanostructures and thin films

    NARCIS (Netherlands)

    Stavenga, Doekele G.; Tinbergen, Jan; Leertouwer, Hein L.; Wilts, Bodo D.

    2011-01-01

    The colours of the common kingfisher, Alcedo atthis, reside in the barbs of the three main types of feather: the orange breast feathers, the cyan back feathers and the blue tail feathers. Scanning electron microscopy showed that the orange barbs contain small pigment granules. The cyan and blue

  13. Preliminary study on chicken feather protein-based wood adhesives

    Science.gov (United States)

    Zehui Jiang; Daochun Qin; Chung-Yun Hse; Monlin Kuo; Zhaohui Luo; Ge Wang; Yan Yu

    2008-01-01

    The objective of this preliminary study was to partially replace phenol in the synthesis of phenol-formaldehyde resin with feather protein. Feather protein–based resins, which contained one part feather protein and two parts phenol, were formulated under the conditions of two feather protein hydrolysis methods (with and without presence of phenol during...

  14. Feather eating and its associations with plumage damage and feathers on the floor in commercial farms of laying hens

    DEFF Research Database (Denmark)

    Riber, Anja Brinch; Hinrichsen, Lena Karina

    2016-01-01

    Feather eating has been associated with feather pecking, which continues to pose economic and welfare problems in egg production. Knowledge on feather eating is limited and studies of feather eating in commercial flocks of laying hens have not been performed previously. Therefore, the main object...

  15. Local pharmacological effects of tungstate on the color-pattern determination of butterfly wings: a possible relationship between the eyespot and parafocal element.

    Science.gov (United States)

    Dhungel, Bidur; Otaki, Joji M

    2009-11-01

    Butterfly wing color patterns can be changed by the application of a temperature shock or pharmacological agents such as tungstate, producing a distinctive type of elemental modification called the TS (temperature shock) type. Heterochronic uncoupling between the signaling and reception steps during the color-pattern determination process has been proposed as a mechanism for TS-type changes. As an extension of this hypothesis, both the parafocal element (PFE) and the eyespot in the same wing compartment are considered to be determined by morphogenic signal(s) emitted from the same eyespot focus. However, these models need to be examined with additional experimental data. Furthermore, there is controversy as to whether the action of tungstate on wing color patterns is direct or Indirect. Using a species of nymphalid butterfly (Junonia orithya), we have devised a simple method for the local application of pharmacological agents directly on developing wings of pupae. Local tungstate application resulted in reduced eyespots and circular dislocated PFEs in the eyespot-less compartments only on the treated wing, demonstrating that tungstate directly induces color-pattern changes on wings. We further examined the eyespot-PFE relationship in normal and cold-shocked Individuals, showing that an eyespot can be superimposed on a PFE and vice versa, probably depending on the timing of their fate determination. Taken together, we propose a two-morphogen model for the normal color-pattern determination, in which the morphogenic signals for the eyespot and PFE are different from each other despite their Identical origin. This two-morphogen model is compatible with the heterochronic uncoupling model for TS-type changes.

  16. Injury profile SIMulator, a Qualitative aggregative modelling framework to predict injury profile as a function of cropping practices, and abiotic and biotic environment. II. Proof of concept: design of IPSIM-wheat-eyespot.

    Science.gov (United States)

    Robin, Marie-Hélène; Colbach, Nathalie; Lucas, Philippe; Montfort, Françoise; Cholez, Célia; Debaeke, Philippe; Aubertot, Jean-Noël

    2013-01-01

    IPSIM (Injury Profile SIMulator) is a generic modelling framework presented in a companion paper. It aims at predicting a crop injury profile as a function of cropping practices and abiotic and biotic environment. IPSIM's modelling approach consists of designing a model with an aggregative hierarchical tree of attributes. In order to provide a proof of concept, a model, named IPSIM-Wheat-Eyespot, has been developed with the software DEXi according to the conceptual framework of IPSIM to represent final incidence of eyespot on wheat. This paper briefly presents the pathosystem, the method used to develop IPSIM-Wheat-Eyespot using IPSIM's modelling framework, simulation examples, an evaluation of the predictive quality of the model with a large dataset (526 observed site-years) and a discussion on the benefits and limitations of the approach. IPSIM-Wheat-Eyespot proved to successfully represent the annual variability of the disease, as well as the effects of cropping practices (Efficiency = 0.51, Root Mean Square Error of Prediction = 24%; bias = 5.0%). IPSIM-Wheat-Eyespot does not aim to precisely predict the incidence of eyespot on wheat. It rather aims to rank cropping systems with regard to the risk of eyespot on wheat in a given production situation through ex ante evaluations. IPSIM-Wheat-Eyespot can also help perform diagnoses of commercial fields. Its structure is simple and permits to combine available knowledge in the scientific literature (data, models) and expertise. IPSIM-Wheat-Eyespot is now available to help design cropping systems with a low risk of eyespot on wheat in a wide range of production situations, and can help perform diagnoses of commercial fields. In addition, it provides a proof of concept with regard to the modelling approach of IPSIM. IPSIM-Wheat-Eyespot will be a sub-model of IPSIM-Wheat, a model that will predict injury profile on wheat as a function of cropping practices and the production situation.

  17. On the uniqueness of color patterns in raptor feathers

    Science.gov (United States)

    Ellis, D.H.

    2009-01-01

    For this study, I compared sequentially molted feathers for a few captive raptors from year to year and symmetrically matched feathers (left/right pairs) for many raptors to see if color patterns of sequential feather pairs were identical or if symmetrical pairs were mirror-image identical. Feather pairs were found to be identical only when without color pattern (e.g., the all-white rectrices of Bald Eagles [Haliaeetus leucocephalus]). Complex patterns were not closely matched, but some simple patterns were sometimes closely matched, although not identical. Previous claims that complex color patterns in feather pairs are fingerprint-identical (and therefore that molted feathers from wild raptors can be used to identify breeding adults from year to year with certainty) were found to be untrue: each feather is unique. Although it is unwise to be certain of bird of origin using normal feathers, abnormal feathers can often be so used. ?? 2009 The Raptor Research Foundation, Inc.

  18. The fearful feather pecker : applying the principles to practice to prevent feather pecking in laying hens

    NARCIS (Netherlands)

    Haas, de E.N.

    2014-01-01

    Billions of laying hens are kept worldwide. Severe feather pecking (SFP) is a behaviour which occurs with a high prevalence on commercial farms. SFP, the pecking and plucking of feathers of another bird, induces pain and stress and can ultimately lead to cannibalism. Moreover, SFP can occur if a

  19. Isolation and characterization of feather degrading bacteria from ...

    African Journals Online (AJOL)

    puchooa

    2012-09-04

    Sep 4, 2012 ... In Mauritius, the annual production of poultry meat is about 50,000 tonnes ... processing of feathers for the production of feather meal, instead of chemical ..... digestibility by bacterial keratinase as a feed additive. FASEB J.

  20. Purification and characterization of a keratinase from the feather ...

    African Journals Online (AJOL)

    Yomi

    2012-01-31

    Jan 31, 2012 ... ... a keratinase from the feather-degrading cultures of Aspergillus flavipes ..... fumigatus (Santos et al., 1996) and A. oryzae (Bressollier et al., 1999). ..... composition and nitrogen characteristics of feather meal. Anim. Feed. Sci.

  1. The most prominent safety guarantees

    International Nuclear Information System (INIS)

    Lucenet, G.

    1978-01-01

    The Creys-Malville Nuclear Centre has been designed using the safety analysis implemented since the beginning of the developments of breeder reactors in France and the Super Phenix follows almost the same safety regulations as its predecessor the Phenix reactor. These regulations are based on: 'Recommendations for the safety standards of the Super Phenix' drawn up by the French Safety Authorities in July 1973. The prominent points are summarised. (C.F.)

  2. Kingfisher feathers - colouration by pigments, spongy nanostructures and thin films

    OpenAIRE

    Stavenga, Doekele G.; Tinbergen, Jan; Leertouwer, Hein L.; Wilts, Bodo D.

    2011-01-01

    The colours of the common kingfisher, Alcedo atthis, reside in the barbs of the three main types of feather: the orange breast feathers, the cyan back feathers and the blue tail feathers. Scanning electron microscopy showed that the orange barbs contain small pigment granules. The cyan and blue barbs contain spongy nanostructures with slightly different dimensions, causing different reflectance spectra. Imaging scatterometry showed that the pigmented barbs create a diffuse orange scattering a...

  3. Feather eating and its associations with plumage damage and feathers on the floor in commercial farms of laying hens

    DEFF Research Database (Denmark)

    Riber, Anja Brinch; Hinrichsen, Lena Karina

    2016-01-01

    Feather eating has been associated with feather pecking, which continues to pose economic and welfare problems in egg production. Knowledge on feather eating is limited and studies of feather eating in commercial flocks of laying hens have not been performed previously. Therefore, the main...... objective was to investigate feather eating and its association with plumage damage and floor feather characteristics in commercial flocks of layers in barn and organic production systems. The study was performed in 13 flocks of barn layers and 17 flocks of organic layers. Each flock was visited at around.......3% in organic; P=0.99). Our hypothesis about a positive correlation between feather eating and plumage damage was not supported as no correlation was found between the prevalence of poor plumage condition and the prevalence of droppings with feather content. However, the prevalence of pecking damaged floor...

  4. Isolation and characterization of feather degrading bacteria from ...

    African Journals Online (AJOL)

    This study is aimed at isolating and characterizing new culturable feather degrading bacteria from soils of the University of Mauritius Farm. Bacteria that were isolated were tested for their capability to grow on feather meal agar (FMA). Proteolytic bacteria were tested for feather degradation and were further identified ...

  5. Alternative fish feed production from waste chicken feathers

    Directory of Open Access Journals (Sweden)

    Sri Jumini

    2017-08-01

    Full Text Available In this This devotion has been done to provide education and training of the utilization of waste chicken manure, making flour chicken feathers as a fish feed alternative, that can overcome some of the problems that waste chicken feathers from the center cutting broiler chickens in the village Krasak enough, it causes pollution, and not used optimally; Low public awareness of awareness of environmental pollution; the lack of public knowledge about the utilization of waste chicken feathers, and processing technology, as well as to address the needs of fish feed more expensive, need alternative feed ingredients. This service program has provided insight to the public about waste chicken feathers so that it can be used as a new entrepreneurial startups. To achieve these objectives have been done of activity as follows: 1 Provide counseling and understanding of the community will be a negative impact on the environment of waste chicken feathers. 2 Provide counseling utilization of waste chicken feathers for people in nearby farms. 3 Make a chicken feather meal of chicken feather waste as an alternative fish feed to improve digestibility of chicken feathers. 3 The formation of the group for increasing the economic income of the family. This service activities program runs quite well with demonstrated some activity, namely: 1 Change Behavior Society (knowledge transfer; 2 Chicken Feather Extension Waste Utilization; 3 Making Unit Waste Chicken Feathers; 4 Establishment of New Business of Diversified Waste Chicken Feathers.

  6. Loss of phototaxis and degeneration of an eyespot in long-term algal cultures: evidence from ultrastructure and behaviour in the dinoflagellate Kryptoperidinium foliaceum.

    Science.gov (United States)

    Moldrup, Morten; Moestrup, Øjvind; Hansen, Per Juel

    2013-01-01

    Phototaxis provides phytoplankton with the means to orient themselves in a light gradient. This is accomplished using an eyespot and associated organelles. For the dinoflagellate Kryptoperidinium foliaceum, which has been described as having one of the most elaborate eyespot complexes known, positive phototaxis has hitherto not been reported. In this study, we show that a newly isolated strain of K. foliaceum is indeed capable of positive phototaxis with a mean vector (± 95% confidence interval) of 352°± 2.2, where 0/360° indicates the position of the light source. A study of three strains (UTEX 1688, CCMP 1326, and MBL07) of K. foliaceum showed that the eyespot in two of these strains has degenerated following decades in culture. Thus, previous studies have failed to report positive phototaxis due to loss of directionality caused by the degenerated eyespot. The results are discussed in a broader context and we conclude that studies on algal morphology and physiology may result in erroneous conclusions if based on algal cultures maintained under laboratory conditions for extended periods. © 2013 The Author(s) Journal of Eukaryotic Microbiology © 2013 International Society of Protistologists.

  7. Fossilized skin reveals coevolution with feathers and metabolism in feathered dinosaurs and early birds.

    Science.gov (United States)

    McNamara, Maria E; Zhang, Fucheng; Kearns, Stuart L; Orr, Patrick J; Toulouse, André; Foley, Tara; Hone, David W E; Rogers, Chris S; Benton, Michael J; Johnson, Diane; Xu, Xing; Zhou, Zhonghe

    2018-05-25

    Feathers are remarkable evolutionary innovations that are associated with complex adaptations of the skin in modern birds. Fossilised feathers in non-avian dinosaurs and basal birds provide insights into feather evolution, but how associated integumentary adaptations evolved is unclear. Here we report the discovery of fossil skin, preserved with remarkable nanoscale fidelity, in three non-avian maniraptoran dinosaurs and a basal bird from the Cretaceous Jehol biota (China). The skin comprises patches of desquamating epidermal corneocytes that preserve a cytoskeletal array of helically coiled α-keratin tonofibrils. This structure confirms that basal birds and non-avian dinosaurs shed small epidermal flakes as in modern mammals and birds, but structural differences imply that these Cretaceous taxa had lower body heat production than modern birds. Feathered epidermis acquired many, but not all, anatomically modern attributes close to the base of the Maniraptora by the Middle Jurassic.

  8. Identification of shed or plucked origin of Indian peafowl (Pavo cristatus) tail feathers: preliminary findings.

    Science.gov (United States)

    Sahajpal, Vivek; Goyal, S P

    2008-06-01

    Indian Peafowl (Pavo cristatus) tail covert feathers were studied to investigate the difference between shed and plucked feathers in the context of wildlife offence cases involving the killing of the Indian national bird for the purpose of plucking feathers. Plucked feathers were distinguished from shed feathers by examining their roots under low magnification of a stereoscopic microscope. A chemical test to show the presence of blood on the roots of plucked feathers was used to corroborate the plucked origin of feathers.

  9. What makes a feather shine? A nanostructural basis for glossy black colours in feathers.

    Science.gov (United States)

    Maia, Rafael; D'Alba, Liliana; Shawkey, Matthew D

    2011-07-07

    Colours in feathers are produced by pigments or by nanostructurally organized tissues that interact with light. One of the simplest nanostructures is a single layer of keratin overlying a linearly organized layer of melanosomes that create iridescent colours of feather barbules through thin-film interference. Recently, it has been hypothesized that glossy (i.e. high specular reflectance) black feathers may be evolutionarily intermediate between matte black and iridescent feathers, and thus have a smooth keratin layer that produces gloss, but not the layered organization of melanosomes needed for iridescence. However, the morphological bases of glossiness remain unknown. Here, we use a theoretical approach to generate predictions about morphological differences between matte and glossy feathers that we then empirically test. Thin-film models predicted that glossy spectra would result from a keratin layer 110-180 nm thick and a melanin layer greater than 115 nm thick. Transmission electron microscopy data show that nanostructure of glossy barbules falls well within that range, but that of matte barbules does not. Further, glossy barbules had a thinner and more regular keratin cortex, as well as a more continuous underlying melanin layer, than matte barbules. Thus, their quasi-ordered nanostructures are morphologically intermediate between matte black and iridescent feathers, and perceived gloss may be a form of weakly chromatic iridescence.

  10. Structural resonance and mode of flutter of hummingbird tail feathers.

    Science.gov (United States)

    Clark, Christopher J; Elias, Damian O; Girard, Madeline B; Prum, Richard O

    2013-09-15

    Feathers can produce sound by fluttering in airflow. This flutter is hypothesized to be aeroelastic, arising from the coupling of aerodynamic forces to one or more of the feather's intrinsic structural resonance frequencies. We investigated how mode of flutter varied among a sample of hummingbird tail feathers tested in a wind tunnel. Feather vibration was measured directly at ~100 points across the surface of the feather with a scanning laser Doppler vibrometer (SLDV), as a function of airspeed, Uair. Most feathers exhibited multiple discrete modes of flutter, which we classified into types including tip, trailing vane and torsional modes. Vibratory behavior within a given mode was usually stable, but changes in independent variables such as airspeed or orientation sometimes caused feathers to abruptly 'jump' from one mode to another. We measured structural resonance frequencies and mode shapes directly by measuring the free response of 64 feathers stimulated with a shaker and recorded with the SLDV. As predicted by the aeroelastic flutter hypothesis, the mode shape (spatial distribution) of flutter corresponded to a bending or torsional structural resonance frequency of the feather. However, the match between structural resonance mode and flutter mode was better for tip or torsional mode shapes, and poorer for trailing vane modes. Often, the 3rd bending structural harmonic matched the expressed mode of flutter, rather than the fundamental. We conclude that flutter occurs when airflow excites one or more structural resonance frequencies of a feather, most akin to a vibrating violin string.

  11. A 'feather-trap' for collecting DNA samples from birds.

    Science.gov (United States)

    Maurer, Golo; Beck, Nadeena; Double, Michael C

    2010-01-01

    Genetic analyses of birds are usually based on DNA extracted from a blood sample. For some species, however, obtaining blood samples is difficult because they are sensitive to handling, pose a conservation or animal welfare concern, or evade capture. In such cases, feathers obtained from live birds in the wild can provide an alternative source of DNA. Here, we provide the first description and evaluation of a 'feather-trap', consisting of small strips of double-sided adhesive tape placed close to a nest with chicks, as a simple, inexpensive and minimally invasive method to collect feathers. The feather-trap was tested in tropical conditions on the Australian pheasant coucal (Centropus phasianinus). None of the 12 pairs of coucals on which the feather-trap was used abandoned the nest, and feeding rates did not differ from those of birds not exposed to a feather-trap. On average, 4.2 feathers were collected per trap over 2-5 days and, despite exposure to monsoonal rain, DNA was extracted from 71.4% of samples, albeit at low concentrations. The amount of genomic DNA extracted from each feather was sufficient to reliably genotype individuals at up to five microsatellite loci for parentage analysis. We show that a feather-trap can provide a reliable alternative for obtaining DNA in species where taking blood is difficult. It may also prove useful for collecting feather samples for other purposes, e.g. stable-isotope analysis. © 2009 Blackwell Publishing Ltd.

  12. Identification of a feather β-keratin gene exclusively expressed in pennaceous barbule cells of contour feathers in chicken.

    Science.gov (United States)

    Kowata, Kinue; Nakaoka, Minori; Nishio, Kaori; Fukao, Ayaka; Satoh, Akira; Ogoshi, Maho; Takahashi, Sumio; Tsudzuki, Masaoki; Takeuchi, Sakae

    2014-05-25

    Feathers are elaborate skin appendages shared by birds and theropod dinosaurs that have hierarchical branching of the rachis, barbs, and barbules. Feather filaments consist of β-keratins encoded by multiple genes, most of which are located in tandem arrays on chromosomes 2, 25, and 27 in chicken. The expansion of the genes is thought to have contributed to feather evolution; however, it is unclear how the individual genes are involved in feather formation. The aim of the present study was to identify feather keratin genes involved in the formation of barbules. Using a combination of microarray analysis, reverse-transcription polymerase chain reaction, and in situ hybridization, we found an uncharacterized keratin gene on chromosome 7 that was expressed specifically in barbule cells in regenerating chicken feathers. We have named the gene barbule specific keratin 1 (BlSK1). The BlSK1 gene structure was similar to the gene structure of previously characterized feather keratin genes, and consisted of a non-coding leader exon, an intron, and an exon with an open reading frame (ORF). The ORF was predicted to encode a 98 aa long protein, which shared 59% identity with feather keratin B. Orthologs of BlSK1 were found in the genomes of other avian species, including turkey, duck, zebra finch, and flycatcher, in regions that shared synteny with chromosome 7 of chicken. Interestingly, BlSK1 was expressed in feather follicles that generated pennaceous barbules but not in follicles that generated plumulaceous barbules. These results suggested that the composition of feather keratins probably varies depending on the structure of the feather filaments and, that individual feather keratin genes may be involved in building different portions and/or types of feathers in chicken. Copyright © 2014 Elsevier B.V. All rights reserved.

  13. Ultrastructure of the feather follicle in relation to the formation of the rachis in pennaceous feathers.

    Science.gov (United States)

    Alibardi, Lorenzo

    2010-06-01

    The present ultrastructural study on follicle of regenerating feathers of four different avian species focuses on the formation and cytology of the rachis. Epithelial cells within the bottom part of the follicle (the collar) are contacted from mesenchymal cells of the dermal papilla. The most basal part of the collar is formed by a circular epithelium containing germinal cells, while in the upper ramogenic part of the collar barb ridges are generated. Epithelial cells rest upon a basement membrane that is stretched in actively forming barb ridges among which anchored mesenchymal cells send thin elongation. This observation suggests that an intense exchange of molecules with the epithelium occurs. The process of formation of the rachis occurs by fusion of barb ridges with the nonsegmented, dorsal or anterior part of the collar. The latter becomes the rachidial ridge, the upper part of the collar where barbs form the branches of the pennaceous feather. The rachis grows and matures into an external cortical part, containing compact corneous material (feather keratin, as confirmed by immunocytochemistry), and a vacuolated medulla with a process similar to that occurring in rami of single barbs. The extension of the medulla and cortex varies along the rachis in different species. In general a thin cortex is formed in those sections of the rachis where barbs are absent, and the feather keratin positive layer increases in the basal part of the feather, the calamus.

  14. Avian Feathers: An Examination of Lightweight Resilience and Bioinspired Designs

    Science.gov (United States)

    Sullivan, Tarah Naoe

    In bird flight, the majority of the wing surface consists of highly refined and hierarchically organized beta-keratinous feathers. Thus, flight feathers contain ingenious combinations of components that optimize lift, stiffness, aerodynamics, and damage resistance. Their design involves two main parts: a central shaft which prescribes stiffness and lateral vanes that allow for the capture of air. Within the feather vane, barbs branch from the shaft and barbules branch from barbs, forming a flat surface and ensuring lift. Microhooks at the end of barbules hold barbs tightly together, providing a close-knit, unified structure and enabling repair of the vane through the reattachment of un-hooked junctions. In this dissertation, unique aspects of feather architecture are explored to uncover principles translatable to the design of modern aerospace materials and structures. Specifically, understudied aspects of the feather's lightweight yet resilient properties are investigated. This research has revealed several novel characteristics of the feather. Allometric scaling relationships are developed linking the geometry of a bird's wing components to its flight characteristics and total mass. Barbule spacing within the feather vane is found to be 8-16 microm for birds ranging from 0.02-11 kg. Additionally, it is discovered that strength is recovered with the shape recovery property of feathers, and a mechanism for this phenomenon is proposed. Barbule adhesion within the vane is found to prevent barbs from twisting in flexure, maintaining the vane's stiffness, and the extent to which unzipping these connections affects the feather's ability to capture air is related to barb shape. Directional permeability of the feather vane is experimentally confirmed and related to the intricate microstructure of barbules. Lastly, the exceptional architecture of the feather motivated the design of novel bioinspired structures with tailored and unique properties. The avian feather serves

  15. Short barb: a feather structure mutation in Japanese quail.

    Science.gov (United States)

    Fulton, J E; Roberts, C W; Nichols, C R; Cheng, K M

    1982-12-01

    A type of feather structure abnormality in Japanese quail resulting in shortened barbs on contour feathers was found to be controlled by a single autosomal recessive gene, sh (short barb). The mutation was first identified in a full-sib family from the University of British Columbia wild type line. Unlike other feather structure mutations in Japanese quail reported previously in literature, the short barb mutation is not associated with poor reproduction.

  16. Spatially modulated structural colour in bird feathers

    Science.gov (United States)

    Parnell, Andrew J.; Washington, Adam L.; Mykhaylyk, Oleksandr O.; Hill, Christopher J.; Bianco, Antonino; Burg, Stephanie L.; Dennison, Andrew J. C.; Snape, Mary; Cadby, Ashley J.; Smith, Andrew; Prevost, Sylvain; Whittaker, David M.; Jones, Richard A. L.; Fairclough, J. Patrick. A.; Parker, Andrew R.

    2015-12-01

    Eurasian Jay (Garrulus glandarius) feathers display periodic variations in the reflected colour from white through light blue, dark blue and black. We find the structures responsible for the colour are continuous in their size and spatially controlled by the degree of spinodal phase separation in the corresponding region of the feather barb. Blue structures have a well-defined broadband ultra-violet (UV) to blue wavelength distribution; the corresponding nanostructure has characteristic spinodal morphology with a lengthscale of order 150 nm. White regions have a larger 200 nm nanostructure, consistent with a spinodal process that has coarsened further, yielding broader wavelength white reflectance. Our analysis shows that nanostructure in single bird feather barbs can be varied continuously by controlling the time the keratin network is allowed to phase separate before mobility in the system is arrested. Dynamic scaling analysis of the single barb scattering data implies that the phase separation arrest mechanism is rapid and also distinct from the spinodal phase separation mechanism i.e. it is not gelation or intermolecular re-association. Any growing lengthscale using this spinodal phase separation approach must first traverse the UV and blue wavelength regions, growing the structure by coarsening, resulting in a broad distribution of domain sizes.

  17. Spatially modulated structural colour in bird feathers.

    Science.gov (United States)

    Parnell, Andrew J; Washington, Adam L; Mykhaylyk, Oleksandr O; Hill, Christopher J; Bianco, Antonino; Burg, Stephanie L; Dennison, Andrew J C; Snape, Mary; Cadby, Ashley J; Smith, Andrew; Prevost, Sylvain; Whittaker, David M; Jones, Richard A L; Fairclough, J Patrick A; Parker, Andrew R

    2015-12-21

    Eurasian Jay (Garrulus glandarius) feathers display periodic variations in the reflected colour from white through light blue, dark blue and black. We find the structures responsible for the colour are continuous in their size and spatially controlled by the degree of spinodal phase separation in the corresponding region of the feather barb. Blue structures have a well-defined broadband ultra-violet (UV) to blue wavelength distribution; the corresponding nanostructure has characteristic spinodal morphology with a lengthscale of order 150 nm. White regions have a larger 200 nm nanostructure, consistent with a spinodal process that has coarsened further, yielding broader wavelength white reflectance. Our analysis shows that nanostructure in single bird feather barbs can be varied continuously by controlling the time the keratin network is allowed to phase separate before mobility in the system is arrested. Dynamic scaling analysis of the single barb scattering data implies that the phase separation arrest mechanism is rapid and also distinct from the spinodal phase separation mechanism i.e. it is not gelation or intermolecular re-association. Any growing lengthscale using this spinodal phase separation approach must first traverse the UV and blue wavelength regions, growing the structure by coarsening, resulting in a broad distribution of domain sizes.

  18. Re-interpreting Prominences Classified as Tornadoes

    Science.gov (United States)

    Martin, Sara F.; Venkataramanasastry, Aparna

    2015-04-01

    Some papers in the recent literature identify tornado prominences with barbs of quiescent prominences while papers in the much older historic literature include a second category of tornado prominence that does not correspond to a barb of a quiescent prominence. The latter are described as prominence mass rotating around a nearly vertical axis prior to its eruption and the rotation was verified by spectral measurements. From H alpha Doppler-shifted mass motions recorded at Helio Research or the Dutch Open Telescope, we illustrate how the apparent tornado-like motions, identified with barbs, are illusions in our mind’s eye resulting from poorly resolved counterstreaming threads of mass in the barbs of quiescent prominences. In contrast, we confirm the second category of rotational motion in prominences shortly before and during eruption. In addition, we identify this second category as part of the late phase of a phenomenon called the roll effect in erupting prominences. In these cases, the eruption begins with the sideways rolling of the top of a prominence. As the eruption proceeds the rolling motion propagates down one leg or both legs of the prominence depending on whether the eruption is asymmetric or symmetric respectively. As an asymmetric eruption continues, the longer lasting leg becomes nearly vertical and its rotational motion also continues. If only this phase of the eruption was observed, as in some historic cases, it was called a tornado prominence. However, when we now observe entire eruptions in time-lapse sequences, the similarity to terrestrial tornadoes is lost. We conclude that neither prominence barbs, that give the illusion of rotation, nor the cases of true rotational motion, in the legs of erupting prominences, are usefully described as tornado prominences when the complete prominence structure or complete erupting event is observed.

  19. Fearfulness and feather damage in laying hens divergently selected for high and low feather pecking

    DEFF Research Database (Denmark)

    Rodenburg, T Bas; de Haas, Elske N; Nielsen, Birte Lindstrøm

    2010-01-01

    Feather pecking (FP) remains a major welfare and economic problem in laying hens. FP has been found to be related to other behavioural characteristics, such as fearfulness. There are indications that fearful birds are more likely to develop FP. Furthermore, FP can lead to increased fearfulness...... in the victims. To investigate further the relationship between FP and fearfulness, feather damage and behavioural fear responses were recorded in three White Leghorn lines of laying hens: a line selected for high FP (HFP line), a line selected for low FP (LFP line) and an unselected control line (10th...... in fear responses between the HFP and LFP lines were not found, neither in the TI-test, nor in the HA or NO test. As expected, birds from the HFP line had considerably more feather damage than birds from the LFP line and birds from the unselected control line were intermediate. Cages that withdrew from...

  20. Biological treatment of chicken feather waste for improved biogas production

    Institute of Scientific and Technical Information of China (English)

    Gergely Forgács; Saeid Alinezhad; Amir Mirabdollah; Elisabeth Feuk-Lagerstedt; Ilona Sárvári Horwáth

    2011-01-01

    A two-stage system was developed which combines the biological degradation of keratin-rich waste with the production of biogas.Chicken feather waste was treated biologically with a recombinant Bacillus megaterium strain showing keratinase activity prior to biogas production.Chopped,autoclaved chicken feathers (4%,W/V) were completely degraded,resulting in a yellowish fermentation broth with a level of 0.51 mg/mL soluble proteins after 8 days of cultivation of the recombinant strain.During the subsequent anaerobic batch digestion experiments,methane production of 0.35 Nm3/kg dry feathers (i.e.,0.4 Nm3/kg volatile solids of feathers),corresponding to 80% of the theoretical value on proteins,was achieved from the feather hydrolyzates,independently of the prehydrolysis time period of 1,2 or 8 days.Cultivation with a native keratinase producing strain,Bacillus licheniformis resulted in only 0.25 mg/mL soluble proteins in the feather hydrolyzate,which then was digested achieving a maximum accumulated methane production of 0.31 Nm3/kg dry feathers.Feather hydrolyzates treated with the wild type B.megaterium produced 0.21 Nm3 CH4/kg dry feathers as maximum yield.

  1. Global associations between birds and vane-dwelling feather mites.

    Science.gov (United States)

    Doña, Jorge; Proctor, Heather; Mironov, Sergey; Serrano, David; Jovani, Roger

    2016-11-01

    Understanding host-symbiont networks is a major question in evolutionary ecology. Birds host a great diversity of endo- and ectosymbiotic organisms, with feather mites (Arachnida: Acariformes: Analgoidea, Pterolichoidea) being among the most diverse of avian symbionts. A global approach to the ecology and evolution of bird-feather-mite associations has been hampered because of the absence of a centralized data repository. Here we present the most extensive data set of associations between feather mites and birds. Data include 12 036 records of 1887 feather mite species located on the flight feathers of 2234 bird species from 147 countries. Feather mites typically located inside quills, on the skin, or on downy body feathers are not included. Data were extracted from 493 published sources dating from 1882 to 2015. Data exploration shows that although most continents and bird families are represented, most bird species remain unexplored for feather mites. Nevertheless, this is the most comprehensive data set available for enabling global macroecological analyses of feather mites and their hosts, such as ecological network analyses. This metadata file outlines the structure of these data and provides primary references for all records used. © 2016 by the Ecological Society of America.

  2. Apparent Solar Tornado-Like Prominences

    Science.gov (United States)

    Panasenco, Olga; Martin, Sara F.; Velli, Marco

    2014-02-01

    Recent high-resolution observations from the Solar Dynamics Observatory (SDO) have reawakened interest in the old and fascinating phenomenon of solar tornado-like prominences. This class of prominences was first introduced by Pettit ( Astrophys. J. 76, 9, 1932), who studied them over many years. Observations of tornado prominences similar to the ones seen by SDO had already been documented by Secchi ( Le Soleil, 1877). High-resolution and high-cadence multiwavelength data obtained by SDO reveal that the tornado-like appearance of these prominences is mainly an illusion due to projection effects. We discuss two different cases where prominences on the limb might appear to have a tornado-like behavior. One case of apparent vortical motions in prominence spines and barbs arises from the (mostly) 2D counterstreaming plasma motion along the prominence spine and barbs together with oscillations along individual threads. The other case of apparent rotational motion is observed in a prominence cavity and results from the 3D plasma motion along the writhed magnetic fields inside and along the prominence cavity as seen projected on the limb. Thus, the "tornado" impression results either from counterstreaming and oscillations or from the projection on the plane of the sky of plasma motion along magnetic-field lines, rather than from a true vortical motion around an (apparent) vertical or horizontal axis. We discuss the link between tornado-like prominences, filament barbs, and photospheric vortices at their base.

  3. Value-added products from chicken feather fiber and protein

    Science.gov (United States)

    Fan, Xiuling

    Worldwide poultry consumption has generated a huge amount of feather "waste" annually. Currently, the feather has a low value-being used for animal feed in the world. The quality of fibrous air filters depend on their main component, fibers. The main physical structure of chicken feathers is barbs which can be used directly as fibers. They have small diameter, which makes them a good choice for air filtration. The main chemical structure of chicken feathers is structural fibrous protein, keratin. Therefore, chicken feathers could potentially be used for protein fiber production. To obtain chicken feather fibers, barbs were stripped from the quills by a stripping device and separated with a blender. Some feather fibers were entangled with polyester staple fibers, and needlepunched to form a nonwoven fabric. Some feather fibers were blended with CelBond(TM) bi-component polyester as binder fibers, and pressed between two hot plates to produce thermobonded nonwovens. Whole chicken feathers were ground into powder and their keratin was reduced in water. The reduced keratin was salt precipitated, dried and dissolved in ionic liquid with/without bleach cotton. The reduced chicken feather keratin ionic liquid solutions were spun into regenerated fibers through dry-jet wet spinning. The needlepunched and thermobonded nonwovens were tested for filtration and other properties. With an increase of areal density and feather fiber composition, the air permeability of the needlepunched nonwovens decreased, and their filtration efficiency and pressure drop both increased. The case can be made that feather fibers gave fabrics better filtration at the same fabric weight, but at the expense of air permeability and pressure drop. The scrim and needlepunching process improved the filtration efficiency. Their strength depended on scrim. The hot-press process was very simple. The thermobonded nonwovens had very high air permeability. In them, there was also an inverse relation between

  4. Prominence mass supply and the cavity

    Energy Technology Data Exchange (ETDEWEB)

    Schmit, Donald J.; Innes, D. [Max Planck Institute for Solar System Research, D-37191 Katlenburg-Lindau (Germany); Gibson, S. [High Altitude Observatory, National Center for Atmospheric Research, Boulder, CO 80307 (United States); Luna, M. [Instituto de Astrofísica de Canarias, E-38200 La Laguna, Tenerife (Spain); Karpen, J. [NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States)

    2013-12-20

    A prevalent but untested paradigm is often used to describe the prominence-cavity system: the cavity is under-dense because it is evacuated by supplying mass to the condensed prominence. The thermal non-equilibrium (TNE) model of prominence formation offers a theoretical framework to predict the thermodynamic evolution of the prominence and the surrounding corona. We examine the evidence for a prominence-cavity connection by comparing the TNE model with diagnostics of dynamic extreme ultraviolet (EUV) emission surrounding the prominence, specifically prominence horns. Horns are correlated extensions of prominence plasma and coronal plasma which appear to connect the prominence and cavity. The TNE model predicts that large-scale brightenings will occur in the Solar Dynamics Observatory Atmospheric Imaging Assembly 171 Å bandpass near the prominence that are associated with the cooling phase of condensation formation. In our simulations, variations in the magnitude of footpoint heating lead to variations in the duration, spatial scale, and temporal offset between emission enhancements in the other EUV bandpasses. While these predictions match well a subset of the horn observations, the range of variations in the observed structures is not captured by the model. We discuss the implications of our one-dimensional loop simulations for the three-dimensional time-averaged equilibrium in the prominence and the cavity. Evidence suggests that horns are likely caused by condensing prominence plasma, but the larger question of whether this process produces a density-depleted cavity requires a more tightly constrained model of heating and better knowledge of the associated magnetic structure.

  5. Feather pecking in growers: a study with individually marked birds

    DEFF Research Database (Denmark)

    Wechsler, B; Huber-Eicher, B; Nash, David Richard

    1998-01-01

    1. The aim of the present study was to investigate whether individual birds specialise in feather pecking. Growers were individually marked and reared in groups of 30 or 31 in pens with a slatted floor. At an age of 4 to 6 weeks feather pecking was frequent in all pens. 2. On average 83% of all g...

  6. Replacement Value of Feather Meal for Fishmeal on the ...

    African Journals Online (AJOL)

    Replacement Value of Feather Meal for Fishmeal on the Performance of Starter Cockerels. ... ratio and feed cost/kg weights gain. Considering the results of final live weight and daily weight gain, it appeared that the 7.5% level of FEM could be the optimal inclusion level feather meal in the diets of growing cockerels.

  7. Improved keratinase production for feather degradation by Bacillus ...

    African Journals Online (AJOL)

    Optimal medium was used to improve the production of keratinase by Bacillus licheniformis ZJUEL31410, which has a promising application in the transformation of feather into soluble protein. The results of single factor design revealed that the concentration of feather at 20 g/l and the initial pH at value 8 was the best for ...

  8. Genetic analysis of feather pecking behavior in laying hens

    NARCIS (Netherlands)

    Buitenhuis, A.J.

    2003-01-01

    This thesis describes the genetic analysis of feather pecking behavior in laying hens. Feather pecking (FP) is a major welfare problem in laying hens.In the European

  9. Early and late feathering in Turkey and chicken

    NARCIS (Netherlands)

    Derks, Martijn F.L.; Herrero-Medrano, Juan M.; Crooijmans, Richard P.M.A.; Vereijken, Addie; Long, Julie A.; Megens, Hendrik Jan; Groenen, Martien A.M.

    2018-01-01

    Background: Sex-linked slow (SF) and fast (FF) feathering rates at hatch have been widely used in poultry breeding for autosexing at hatch. In chicken, the sex-linked K (SF) and k+ (FF) alleles are responsible for the feathering rate phenotype. Allele K is dominant and a partial duplication of the

  10. Feather pecking and monoamines - a behavioral and neurobiological approach

    NARCIS (Netherlands)

    Kops, M.S.|info:eu-repo/dai/nl/341590649

    2014-01-01

    Severe feather pecking (SFP) remains one of the major welfare issues in laying hens. SFP is the pecking at and pulling out of feathers, inflicting damage to the plumage and skin of the recipient. The neurobiological profile determining the vulnerability of individual hens to develop into a severe

  11. Valorisation of chicken feathers: Characterisation of chemical properties.

    Science.gov (United States)

    Tesfaye, Tamrat; Sithole, Bruce; Ramjugernath, Deresh; Chunilall, Viren

    2017-10-01

    The characterisation of the chemical properties of the whole chicken feather and its fractions (barb and rachis), was undertaken to identify opportunities for valorizing this waste product. The authors have described the physical, morphological, mechanical, electrical and thermal properties of the chicken feathers and related them to potential valorisation routes of the waste. However, identification of their chemical properties is necessary to complete a comprehensive description of chicken feather fractions. Hence, the chicken feathers were thoroughly characterised by proximate and ultimate analyses, elemental composition, spectroscopic analyses, durability in different solvents, burning test, and hydrophobicity. The proximate analysis of chicken feathers revealed the following compositions: crude lipid (0.83%), crude fibre (2.15%), crude protein (82.36%), ash (1.49%), NFE (1.02%) and moisture content (12.33%) whereas the ultimate analyses showed: carbon (64.47%), nitrogen (10.41%), oxygen (22.34%), and sulphur (2.64%). FTIR analysis revealed that the chicken feather fractions contain amide and carboxylic groups indicative of proteinious functional groups; XRD showed a crystallinity index of 22. Durability and burning tests confirmed that feathers behaved similarly to animal fibre. This reveals that chicken feather can be a valuable raw material in textile, plastic, cosmetics, pharmaceuticals, biomedical and bioenergy industries. Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. Genome-wide association mapping of resistance to eyespot disease (Pseudocercosporella herpotrichoides) in European winter wheat (Triticum aestivum L.) and fine-mapping of Pch1.

    Science.gov (United States)

    Zanke, Christine D; Rodemann, Bernd; Ling, Jie; Muqaddasi, Quddoos H; Plieske, Jörg; Polley, Andreas; Kollers, Sonja; Ebmeyer, Erhard; Korzun, Viktor; Argillier, Odile; Stiewe, Gunther; Zschäckel, Thomas; Ganal, Martin W; Röder, Marion S

    2017-03-01

    Genotypes with recombination events in the Triticum ventricosum introgression on chromosome 7D allowed to fine-map resistance gene Pch1, the main source of eyespot resistance in European winter wheat cultivars. Eyespot (also called Strawbreaker) is a common and serious fungal disease of winter wheat caused by the necrotrophic fungi Oculimacula yallundae and Oculimacula acuformis (former name Pseudocercosporella herpotrichoides). A genome-wide association study (GWAS) for eyespot was performed with 732 microsatellite markers (SSR) and 7761 mapped SNP markers derived from the 90 K iSELECT wheat array using a panel of 168 European winter wheat varieties as well as three spring wheat varieties and phenotypic evaluation of eyespot in field tests in three environments. Best linear unbiased estimations (BLUEs) were calculated across all trials and ranged from 1.20 (most resistant) to 5.73 (most susceptible) with an average value of 4.24 and a heritability of H 2  = 0.91. A total of 108 SSR and 235 SNP marker-trait associations (MTAs) were identified by considering associations with a -log 10 (P value) ≥3.0. Significant MTAs for eyespot-score BLUEs were found on chromosomes 1D, 2A, 2D, 3D, 5A, 5D, 6A, 7A and 7D for the SSR markers and chromosomes 1B, 2A, 2B, 2D, 3B and 7D for the SNP markers. For 18 varieties (10.5%), a highly resistant phenotype was detected that was linked to the presence of the resistance gene Pch1 on chromosome 7D. The identification of genotypes with recombination events in the introgressed genomic segment from Triticum ventricosum harboring the Pch1 resistance gene on chromosome 7DL allowed the fine-mapping of this gene using additional SNP markers and a potential candidate gene Traes_7DL_973A33763 coding for a CC-NBS-LRR class protein was identified.

  13. Prominence Mass Supply and the Cavity

    Science.gov (United States)

    Schmit, Donald J.; Gibson, S.; Luna, M.; Karpen, J.; Innes, D.

    2013-01-01

    A prevalent but untested paradigm is often used to describe the prominence-cavity system; the cavity is under-dense because it it evacuated by supplying mass to the condensed prominence. The thermal non-equilibrium (TNE) model of prominence formation offers a theoretical framework to predict the thermodynamic evolutin of the prominence and the surrounding corona. We examine the evidence for a prominence-cavity connection by comparing the TNE model and diagnostics of dynamic extreme ultraviolet (EUV) emission surrounding the prominence, specifically prominence horns. Horns are correlated extensions of prminence plasma and coronal plasma which appear to connect the prominence and cavity. The TNE model predicts that large-scale brightenings will occur in the Solar Dynamics Observatory Atmospheric Imaging Assembly 171 A badpass near he prominence that are associated with the cooling phase of condensation formation. In our simulations, variations in the magnitude of footpoint heating lead to variations in the duration, spatial scale, and temporal offset between emission enhancements in the other EUV bandpasses. While these predictions match well a subset of the horn observations, the range of variations in the observed structures is not captured by the model. We discuss the implications of one-dimensional loop simulations for the three-dimensional time-averaged equilibrium in the prominence and the cavity. Evidence suggests that horns are likely caused by condensing prominence plasma, but the larger question of whether this process produces a density-depleted cavity requires a more tightly constrained model of heating and better knowledge of the associated magnetic structure.

  14. TANGLED MAGNETIC FIELDS IN SOLAR PROMINENCES

    International Nuclear Information System (INIS)

    Van Ballegooijen, A. A.; Cranmer, S. R.

    2010-01-01

    Solar prominences are an important tool for studying the structure and evolution of the coronal magnetic field. Here we consider so-called hedgerow prominences, which consist of thin vertical threads. We explore the possibility that such prominences are supported by tangled magnetic fields. A variety of different approaches are used. First, the dynamics of plasma within a tangled field is considered. We find that the contorted shape of the flux tubes significantly reduces the flow velocity compared to the supersonic free fall that would occur in a straight vertical tube. Second, linear force-free models of tangled fields are developed, and the elastic response of such fields to gravitational forces is considered. We demonstrate that the prominence plasma can be supported by the magnetic pressure of a tangled field that pervades not only the observed dense threads but also their local surroundings. Tangled fields with field strengths of about 10 G are able to support prominence threads with observed hydrogen density of the order of 10 11 cm -3 . Finally, we suggest that the observed vertical threads are the result of Rayleigh-Taylor instability. Simulations of the density distribution within a prominence thread indicate that the peak density is much larger than the average density. We conclude that tangled fields provide a viable mechanism for magnetic support of hedgerow prominences.

  15. Magnetohydrodynamic (MHD) simulation of solar prominence formation

    International Nuclear Information System (INIS)

    Bao, J.

    1987-01-01

    Formation of Kippenhahn-Schluter type solar prominences by chromospheric mass injection is studied via numerical simulation. The numerical model is based on a two-dimensional, time-dependent magnetohydrodynamic (MHD) theory. In addition, an analysis of gravitational thermal MHD instabilities related to condensation is performed by using the small-perturbation method. The conclusions are: (1) Both quiescent and active-region prominences can be formed by chromospheric mass injection, provided certain optimum conditions are satisfied. (2) Quiescent prominences cannot be formed without condensation, though enough mass is supplied from chromosphere. The mass of a quiescent prominence is composed of both the mass injected from the chromosphere and the mass condensed from the corona. On the other hand, condensation is not important to active region prominence formation. (3) In addition to channeling and supporting effects, the magnetic field plays another important role, i.e. containing the prominence material. (4) In the model cases, prominences are supported by the Lorentz force, the gas-pressure gradient and the mass-injection momentum. (5) Due to gravity, more MHD condensation instability modes appear in addition to the basic condensation mode

  16. Diet composition and feeding habits of the eyespot skate, Atlantoraja cyclophora (Elasmobranchii: Arhynchobatidae, off Uruguay and northern Argentina

    Directory of Open Access Journals (Sweden)

    Santiago A. Barbini

    Full Text Available ABSTRACT The eyespot skate, Atlantoraja cyclophora, is an endemic species from the southwestern Atlantic, occurring from Rio de Janeiro, Brazil, to northern Patagonia, Argentina. The feeding habits of this species, from off Uruguay and north Argentina, were evaluated using a multiple hypothesis modelling approach. In general, the diet was composed mainly of decapod crustaceans, followed by teleost fishes. Molluscs, mysidaceans, amphipods, isopods, lancelets and elasmobranchs were consumed in lower proportion. The consumption of shrimps drecreased with increasing body size of A. cyclophora. On the other hand, the consumption of teleosts increased with body size. Mature individuals preyed more heavily on crabs than immature individuals. Teleosts were consumed more in the south region (34º - 38ºS and crabs in the north region (38º - 41ºS. Shrimps were eaten more in the warm season than in the cold season. Prey size increased with increasing body size of A. cyclophora , but large individuals also consumed small teleosts and crabs. Atlantoraja cyclophora has demersal-benthic feeding habits, shifts its diet with increasing body size and in response to seasonal and regional changes in prey availability and distribution.

  17. Nonlinear MHD Waves in a Prominence Foot

    Science.gov (United States)

    Ofman, L.; Knizhnik, K.; Kucera, T.; Schmieder, B.

    2015-11-01

    We study nonlinear waves in a prominence foot using a 2.5D MHD model motivated by recent high-resolution observations with Hinode/Solar Optical Telescope in Ca ii emission of a prominence on 2012 October 10 showing highly dynamic small-scale motions in the prominence material. Observations of Hα intensities and of Doppler shifts show similar propagating fluctuations. However, the optically thick nature of the emission lines inhibits a unique quantitative interpretation in terms of density. Nevertheless, we find evidence of nonlinear wave activity in the prominence foot by examining the relative magnitude of the fluctuation intensity (δI/I ˜ δn/n). The waves are evident as significant density fluctuations that vary with height and apparently travel upward from the chromosphere into the prominence material with quasi-periodic fluctuations with a typical period in the range of 5-11 minutes and wavelengths <2000 km. Recent Doppler shift observations show the transverse displacement of the propagating waves. The magnetic field was measured with the THEMIS instrument and was found to be 5-14 G. For the typical prominence density the corresponding fast magnetosonic speed is ˜20 km s-1, in qualitative agreement with the propagation speed of the detected waves. The 2.5D MHD numerical model is constrained with the typical parameters of the prominence waves seen in observations. Our numerical results reproduce the nonlinear fast magnetosonic waves and provide strong support for the presence of these waves in the prominence foot. We also explore gravitational MHD oscillations of the heavy prominence foot material supported by dipped magnetic field structure.

  18. NONLINEAR MHD WAVES IN A PROMINENCE FOOT

    Energy Technology Data Exchange (ETDEWEB)

    Ofman, L. [Catholic University of America, Washington, DC 20064 (United States); Knizhnik, K.; Kucera, T. [NASA Goddard Space Flight Center, Code 671, Greenbelt, MD 20771 (United States); Schmieder, B. [LESIA, Observatoire de Paris, PSL Research University, CNRS, Sorbonne Universités, UPMC Univ. Paris 06, Univ. Paris-Diderot, Sorbonne Paris Cit, 5 place Jules Janssen, F-92195 Meudon (France)

    2015-11-10

    We study nonlinear waves in a prominence foot using a 2.5D MHD model motivated by recent high-resolution observations with Hinode/Solar Optical Telescope in Ca ii emission of a prominence on 2012 October 10 showing highly dynamic small-scale motions in the prominence material. Observations of Hα intensities and of Doppler shifts show similar propagating fluctuations. However, the optically thick nature of the emission lines inhibits a unique quantitative interpretation in terms of density. Nevertheless, we find evidence of nonlinear wave activity in the prominence foot by examining the relative magnitude of the fluctuation intensity (δI/I ∼ δn/n). The waves are evident as significant density fluctuations that vary with height and apparently travel upward from the chromosphere into the prominence material with quasi-periodic fluctuations with a typical period in the range of 5–11 minutes and wavelengths <2000 km. Recent Doppler shift observations show the transverse displacement of the propagating waves. The magnetic field was measured with the THEMIS instrument and was found to be 5–14 G. For the typical prominence density the corresponding fast magnetosonic speed is ∼20 km s{sup −1}, in qualitative agreement with the propagation speed of the detected waves. The 2.5D MHD numerical model is constrained with the typical parameters of the prominence waves seen in observations. Our numerical results reproduce the nonlinear fast magnetosonic waves and provide strong support for the presence of these waves in the prominence foot. We also explore gravitational MHD oscillations of the heavy prominence foot material supported by dipped magnetic field structure.

  19. Methodological considerations for measuring glucocorticoid metabolites in feathers

    Science.gov (United States)

    Berk, Sara A.; McGettrick, Julie R.; Hansen, Warren K.; Breuner, Creagh W.

    2016-01-01

    In recent years, researchers have begun to use corticosteroid metabolites in feathers (fCORT) as a metric of stress physiology in birds. However, there remain substantial questions about how to measure fCORT most accurately. Notably, small samples contain artificially high amounts of fCORT per millimetre of feather (the small sample artefact). Furthermore, it appears that fCORT is correlated with circulating plasma corticosterone only when levels are artificially elevated by the use of corticosterone implants. Here, we used several approaches to address current methodological issues with the measurement of fCORT. First, we verified that the small sample artefact exists across species and feather types. Second, we attempted to correct for this effect by increasing the amount of methanol relative to the amount of feather during extraction. We consistently detected more fCORT per millimetre or per milligram of feather in small samples than in large samples even when we adjusted methanol:feather concentrations. We also used high-performance liquid chromatography to identify hormone metabolites present in feathers and measured the reactivity of these metabolites against the most commonly used antibody for measuring fCORT. We verified that our antibody is mainly identifying corticosterone (CORT) in feathers, but other metabolites have significant cross-reactivity. Lastly, we measured faecal glucocorticoid metabolites in house sparrows and correlated these measurements with corticosteroid metabolites deposited in concurrently grown feathers; we found no correlation between faecal glucocorticoid metabolites and fCORT. We suggest that researchers should be cautious in their interpretation of fCORT in wild birds and should seek alternative validation methods to examine species-specific relationships between environmental challenges and fCORT. PMID:27335650

  20. Advanced slab polyurethane foam with feather touch; Soft feather urethane foam no kaihatsu

    Energy Technology Data Exchange (ETDEWEB)

    Yamada, Y; Ono, H [Toyota Motor Corp., Aichi (Japan); Mori, A; Yamaguchi, N; Nakamura, T [Bridgestone Corp., Tokyo (Japan)

    1997-10-01

    Automotive seat plays an important part, which are not only retention of sitting position, but also comfort and high-class feeling. Wadding, which is a part of the seat, is a key component for the sitting comfortableness. This paper is concerned with advanced slab polyurethane foam with feather touch feeling. The compounding of formation, foaming process and reliability of mass production is studied. 2 refs., 10 figs., 3 tabs.

  1. A lightweight, biological structure with tailored stiffness: The feather vane.

    Science.gov (United States)

    Sullivan, Tarah N; Pissarenko, Andreï; Herrera, Steven A; Kisailus, David; Lubarda, Vlado A; Meyers, Marc A

    2016-09-01

    The flying feathers of birds are keratinous appendages designed for maximum performance with a minimum weight penalty. Thus, their design contains ingenious combinations of components that optimize lift, stiffness, aerodynamics, and damage resistance. This design involves two main parts: a central shaft that prescribes stiffness and lateral vanes which allows for the capture of air. Within the feather vane, barbs branch from the shaft and barbules branch from barbs, forming a flat surface which ensures lift. Microhooks at the end of barbules hold barbs tightly together, providing the close-knit, unified structure of the feather vane and enabling a repair of the structure through the reattachment of un-hooked junctions. Both the shaft and barbs are lightweight biological structures constructed of keratin using the common motif of a solid shell and cellular interior. The cellular core increases the resistance to buckling with little added weight. Here we analyze the detailed structure of the feather barb and, for the first time, explain its flexural stiffness in terms of the mechanics of asymmetric foam-filled beams subjected to bending. The results are correlated and validated with finite element modeling. We compare the flexure of single barbs as well as arrays of barbs and find that the interlocking adherence of barbs to one another enables a more robust structure due to minimized barb rotation during deflection. Thus, the flexure behavior of the feather vane can be tailored by the adhesive hooking between barbs, creating a system that mitigates damage. A simplified three-dimensional physical model for this interlocking mechanism is constructed by additive manufacturing. The exceptional architecture of the feather vane will motivate the design of bioinspired structures with tailored and unique properties ranging from adhesives to aerospace materials. Despite its importance to bird flight, literature characterizing the feather vane is extremely limited. The feather

  2. Topic prominence in Chinese EFL learners’ interlanguage

    Directory of Open Access Journals (Sweden)

    Shaopeng Li

    2014-01-01

    Full Text Available The present study aims to investigate the general characteristics of topicprominent typological interlanguage development of Chinese learners of English in terms of acquiring subject-prominent English structures from a discourse perspective. Topic structures mainly appear in Chinese discourse in the form of topic chains (Wang, 2002; 2004. The research target are the topic chain, which is the main topic-prominent structure in Chinese discourse, and zero anaphora, which is the most common topic anaphora in the topic chain. Two important findings emerged from the present study. First, the characteristics of Chinese topic chains are transferrable to the interlanguage of Chinese EFL learners, thus resulting in overgeneralization of the zero anaphora. Second, the interlanguage discourse of Chinese EFL learners reflects a change of the second language acquisition process from topic-prominence to subject-prominence, thus lending support to the discourse transfer hypothesis.

  3. EUV observations of quiescent prominences from Skylab

    International Nuclear Information System (INIS)

    Moe, O.K.

    1979-01-01

    The authors report measurements of line intensities and line widths for three quiescent prominences observed with the Naval Research Laboratory slit spectrograph on ATM/Skylab. The wavelengths of the observed lines cover the range 1175 A to 1960 A. The measured intensities have been calibrated to within approximately a factor 2 and are average intensities over a 2 arc sec by 60 arc set slit. Nonthermal velocities are derived from the measured line widths. The nonthermal velocity is found to increase with temperature in the prominence transition zone. Electron densities and pressures are derived from density sensitive line ratios. Electron pressures for two of the prominences are found to lie in the range 0.04-0.08 dyn cm -2 , while values for the third and most intense and active of the three prominences are in the range 0.07-0.22 dyn cm -2 . (Auth.)

  4. North Fork Feather River Erosion Control Program

    International Nuclear Information System (INIS)

    Harrison, L.

    1991-01-01

    PG and E, an investor owned gas and electric utility serving northern and central California, has been engaged since 1984 in the development and implementation of a regional erosion control program for the 954 square mile northern Sierra Nevada watersheed of the East Branch of the North Fork Feather River in Plumas County, California. PG and E entered into an agreement with 13 governmental agencies and a number of private landowners using Coordinated Resource Management and Planning: to cooperatively develop, fund and implement the program. The group has completed several field projects and has a number of additional projects in various stages of development. This paper reports that the program provides multiple environmental and economic benefits including reduction of soil erosion and sedimentation, improved fisheries, enhancement of riparian habitat, increased land values, improved recreation opportunities, and preservation of watershed resources

  5. Theory of the development of curved barbs and their effects on feather morphology.

    Science.gov (United States)

    Feo, Teresa J; Simon, Emma; Prum, Richard O

    2016-08-01

    Feathers exhibit an extraordinary diversity of shapes, which are used by birds to accomplish a diverse set of functions. Pennaceous feathers have a double branched morphology that develops from a tube of epidermis, and variation in branch geometry determines feather shape. Feather development is both complex (i.e., a simple developmental modification can have multiple effects on mature feather shape), and redundant (i.e., different developmental modifications can create the same shape). Due to this, it is not readily apparent how different feather shapes develop. In many feathers, barbs are not straight, but instead curve in toward, or away, from the feather tip. Barb curvature can affect the shape of mature feathers but the development of curved barbs is unknown. Previous research has hypothesized that barb curvature could develop either during the helical growth of barb ridges in the tubular feather germ, or during barb angle expansion as the feather unfurls from the sheath. To better understand the development of curved barbs and their effects on mature feathers we present a theoretical model of curved barb development and test the model with empirical investigations of feathers. We find that curved barbs affect many aspects of feather morphology including vane width, barb length, and barb spacing. In real feathers, curved barbs can develop both during helical barb ridge growth and during barb angle expansion, with most of the observed curvature due to barb angle expansion. Our results demonstrate that barb angle expansion as a feather unfurls from the sheath is a complex and dynamic process that plays an important role in determining the shape and structure of mature feathers. Curved barbs create heterogeneity in barb geometry within the feather vane, which could have important implications for aerodynamic function and the development of within feather pigmentation patterns. J. Morphol. 277:995-1013, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley

  6. Temporal overlap and repeatability of feather corticosterone levels: practical considerations for use as a biomarker.

    Science.gov (United States)

    Harris, Christopher M; Madliger, Christine L; Love, Oliver P

    2016-01-01

    The measurement of corticosterone (CORT) levels in feathers has recently become an appealing tool for the conservation toolbox, potentially providing a non-invasive, integrated measure of stress activity throughout the time of feather growth. However, because the mechanism of CORT deposition, storage and stability in feathers is not fully understood, it is unclear how reliable this measure may be, especially when there is an extended interval between growth and feather collection. We compared CORT levels of naturally grown feathers from tree swallows ( Tachycineta bicolor ) that were moulted and regrown concurrently and therefore expected to have similar CORT levels. Specifically, we compared the same feather from the left and right wing (moulted symmetrically) and different types of feathers (wing, back and tail) expected to have been moulted within the same time period. We found that larger, heavier feathers held more CORT per unit length. In addition, we found a lack of concordance in CORT levels both within the same feather type and between different feather types, even after taking into account differences in feather density. Our results indicate that naturally grown feathers may not consistently provide an indication of stress status. Additionally, conflict in results may arise depending on the feather assayed, and total feather volume may be an important consideration when interpreting feather CORT levels. Future work is necessary to determine explicitly the mechanisms of CORT deposition, the effects of environmental exposure and feather wear on the permanence of the feather CORT signal, and the influence of responses to wild stressors on feather CORT levels, before feather CORT can be implemented effectively as a tool for ecological and conservation applications.

  7. Purification and characterization of a keratinase from the feather ...

    African Journals Online (AJOL)

    Yomi

    2012-01-31

    Jan 31, 2012 ... Keratinase was purified and characterized from the solid cultures of ... Feather from the poultry processing plant is the common source ... keratinous wastes by proteolytic enzymes is a potent ... After treatment with keratinase,.

  8. Effects of oil and oil burn residues on seabird feathers

    DEFF Research Database (Denmark)

    Fritt-Rasmussen, Janne; Linnebjerg, Jannie Fries; Sørensen, Martin X.

    2016-01-01

    It is well known, that in case of oil spill, seabirds are among the groups of animals most vulnerable. Even small amounts of oil can have lethal effects by destroying the waterproofing of their plumage, leading to loss of insulation and buoyancy. In the Arctic these impacts are intensified....... To protect seabirds, a rapid removal of oil is crucial and in situ burning could be an efficient method. In the present work exposure effects of oil and burn residue in different doses was studied on seabird feathers from legally hunted Common eider (Somateria mollissima) by examining changes in total weight...... of the feather and damages on the microstructure (Amalgamation Index) of the feathers before and after exposure. The results of the experiments indicate that burn residues from in situ burning of an oil spill have similar or larger fouling and damaging effects on seabird feathers, as compared to fresh oil....

  9. Feather wastes digestion by new isolated strains Bacillus sp. in ...

    African Journals Online (AJOL)

    Feather wastes digestion by new isolated strains Bacillus sp. in Morocco. ... The most efficient isolated strain selected was compared with Bacillus subtilis ATCC 6633. Results showed ... African Journal of Biotechnology Vol.3(1) 2004: 67-70 ...

  10. Feather growth influences blood mercury level of young songbirds.

    Science.gov (United States)

    Condon, Anne M; Cristol, Daniel A

    2009-02-01

    Dynamics of mercury in feathers and blood of free-living songbirds is poorly understood. Nestling eastern bluebirds (Sialia sialis) living along the mercury-contaminated South River (Virginia, USA) had blood mercury levels an order of magnitude lower than their parents (nestling: 0.09 +/- 0.06 mg/kg [mean +/- standard deviation], n = 156; adult: 1.21 +/- 0.57 mg/kg, n = 86). To test whether this low blood mercury was the result of mercury sequestration in rapidly growing feathers, we repeatedly sampled free-living juveniles throughout the period of feather growth and molt. Mean blood mercury concentrations increased to 0.52 +/- 0.36 mg/kg (n = 44) after the completion of feather growth. Some individuals had reached adult blood mercury levels within three months of leaving the nest, but levels dropped to 0.20 +/- 0.09 mg/kg (n = 11) once the autumn molt had begun. Most studies of mercury contamination in juvenile birds have focused on recently hatched young with thousands of rapidly growing feathers. However, the highest risk period for mercury intoxication in young birds may be during the vulnerable period after fledging, when feathers no longer serve as a buffer against dietary mercury. We found that nestling blood mercury levels were not indicative of the extent of contamination because a large portion of the ingested mercury ended up in feathers. The present study demonstrates unequivocally that in songbirds blood mercury level is influenced strongly by the growth and molt of feathers.

  11. Chemical regulation of body feather microbiota in a wild bird.

    Science.gov (United States)

    Jacob, Staffan; Sallé, Louis; Zinger, Lucie; Chaine, Alexis S; Ducamp, Christine; Boutault, Léa; Russell, Andrew F; Heeb, Philipp

    2018-04-01

    The microbiota has a broad range of impacts on host physiology and behaviour, pointing out the need to improve our comprehension of the drivers of host-microbiota composition. Of particular interest is whether the microbiota is acquired passively, or whether and to what extent hosts themselves shape the acquisition and maintenance of their microbiota. In birds, the uropygial gland produces oily secretions used to coat feathers that have been suggested to act as an antimicrobial defence mechanism regulating body feather microbiota. However, our comprehension of this process is still limited. In this study, we for the first time coupled high-throughput sequencing of the microbiota of both body feathers and the direct environment (i.e., the nest) in great tits with chemical analyses of the composition of uropygial gland secretions to examine whether host chemicals have either specific effects on some bacteria or nonspecific broad-spectrum effects on the body feather microbiota. Using a network approach investigating the patterns of co-occurrence or co-exclusions between chemicals and bacteria within the body feather microbiota, we found no evidence for specific promicrobial or antimicrobial effects of uropygial gland chemicals. However, we found that one group of chemicals was negatively correlated to bacterial richness on body feathers, and a higher production of these chemicals was associated with a poorer body feather bacterial richness compared to the nest microbiota. Our study provides evidence that chemicals produced by the host might function as a nonspecific broad-spectrum antimicrobial defence mechanism limiting colonization and/or maintenance of bacteria on body feathers, providing new insight about the drivers of the host's microbiota composition in wild organisms. © 2018 John Wiley & Sons Ltd.

  12. Fossil evidence for evolution of the shape and color of penguin feathers.

    Science.gov (United States)

    Clarke, Julia A; Ksepka, Daniel T; Salas-Gismondi, Rodolfo; Altamirano, Ali J; Shawkey, Matthew D; D'Alba, Liliana; Vinther, Jakob; DeVries, Thomas J; Baby, Patrice

    2010-11-12

    Penguin feathers are highly modified in form and function, but there have been no fossils to inform their evolution. A giant penguin with feathers was recovered from the late Eocene (~36 million years ago) of Peru. The fossil reveals that key feathering features, including undifferentiated primary wing feathers and broad body contour feather shafts, evolved early in the penguin lineage. Analyses of fossilized color-imparting melanosomes reveal that their dimensions were similar to those of non-penguin avian taxa and that the feathering may have been predominantly gray and reddish-brown. In contrast, the dark black-brown color of extant penguin feathers is generated by large, ellipsoidal melanosomes previously unknown for birds. The nanostructure of penguin feathers was thus modified after earlier macrostructural modifications of feather shape linked to aquatic flight.

  13. Molecular Biology of Feather Morphogenesis: A Testable Model for Evo-Devo Research

    Science.gov (United States)

    WIDELITZ, RANDALL B.; JIANG, TING XIN; YU, MINGKE; SHEN, TED; SHEN, JEN-YEE; WU, PING; YU, ZHICAO; CHUONG, CHENG-MING

    2015-01-01

    Darwin’s theory describes the principles that are responsible for evolutionary change of organisms and their attributes. The actual mechanisms, however, need to be studied for each species and each organ separately. Here we have investigated the mechanisms underlying these principles in the avian feather. Feathers comprise one of the most complex and diverse epidermal organs as demonstrated by their shape, size, patterned arrangement and pigmentation. Variations can occur at several steps along each level of organization, leading to highly diverse forms and functions. Feathers develop gradually during ontogeny through a series of steps that may correspond to the evolutionary steps that were taken during the phylogeny from a reptilian ancestor to birds. These developmental steps include 1) the formation of feather tract fields on the skin surfaces; 2) periodic patterning of the individual feather primordia within the feather tract fields; 3) feather bud morphogenesis establishing anterio - posterior (along the cranio - caudal axis) and proximo - distal axes; 4) branching morphogenesis to create the rachis, barbs and barbules within a feather bud; and 5) gradual modulations of these basic morphological parameters within a single feather or across a feather tract. Thus, possibilities for variation in form and function of feathers occur at every developmental step. In this paper, principles guiding feather tract formation, distributions of individual feathers within the tracts and variations in feather forms are discussed at a cellular and molecular level. PMID:12949772

  14. Eggshell bacterial load is related to antimicrobial properties of feathers lining barn swallow nests.

    Science.gov (United States)

    Peralta-Sánchez, Juan Manuel; Soler, Juan José; Martín-Platero, Antonio Manuel; Knight, Rob; Martínez-Bueno, Manuel; Møller, Anders Pape

    2014-02-01

    The use of feathers to line bird's nests has traditionally been interpreted as having a thermoregulatory function. Feather-degrading bacteria growing on feathers lining nests may have antimicrobial properties, which may provide an additional benefit to lining nests with feathers. We test the hypothesis that the production of antimicrobial substances by feather bacteria affects the microbiological environment of the nest, and therefore the bacterial density on eggshells and, indirectly, hatching success. These effects would be expected to differ between nests lined with pigmented and white feathers, because bacteria grow differently on feathers of different colors. We experimentally manipulated the composition of pigmented and unpigmented feathers in nests of the barn swallow (Hirundo rustica) and studied the antimicrobial properties against the keratin-degrading bacterium Bacillus licheniformis of bacteria isolated from feathers of each color. Analyzed feathers were collected at the end of the incubation period, and antimicrobial activity was defined as the proportion of bacteria from the feathers that produce antibacterial substances effective against B. licheniformis. Our experimental manipulation affected antimicrobial activity, which was higher in nests with only white feathers at the beginning of incubation. Moreover, white feathers showed higher antimicrobial activity than black ones. Interestingly, antimicrobial activity in feathers of one of the colors correlated negatively with bacterial density on feather of the opposite color. Finally, antimicrobial activity of white feathers was negatively related to eggshell bacterial load. These results suggest that antimicrobial properties of feathers in general and of white feathers in particular affect the bacterial environment in nests. This environment in turn affects the bacterial load on eggshells, which may affect hatching success.

  15. Automated image based prominent nucleoli detection.

    Science.gov (United States)

    Yap, Choon K; Kalaw, Emarene M; Singh, Malay; Chong, Kian T; Giron, Danilo M; Huang, Chao-Hui; Cheng, Li; Law, Yan N; Lee, Hwee Kuan

    2015-01-01

    Nucleolar changes in cancer cells are one of the cytologic features important to the tumor pathologist in cancer assessments of tissue biopsies. However, inter-observer variability and the manual approach to this work hamper the accuracy of the assessment by pathologists. In this paper, we propose a computational method for prominent nucleoli pattern detection. Thirty-five hematoxylin and eosin stained images were acquired from prostate cancer, breast cancer, renal clear cell cancer and renal papillary cell cancer tissues. Prostate cancer images were used for the development of a computer-based automated prominent nucleoli pattern detector built on a cascade farm. An ensemble of approximately 1000 cascades was constructed by permuting different combinations of classifiers such as support vector machines, eXclusive component analysis, boosting, and logistic regression. The output of cascades was then combined using the RankBoost algorithm. The output of our prominent nucleoli pattern detector is a ranked set of detected image patches of patterns of prominent nucleoli. The mean number of detected prominent nucleoli patterns in the top 100 ranked detected objects was 58 in the prostate cancer dataset, 68 in the breast cancer dataset, 86 in the renal clear cell cancer dataset, and 76 in the renal papillary cell cancer dataset. The proposed cascade farm performs twice as good as the use of a single cascade proposed in the seminal paper by Viola and Jones. For comparison, a naive algorithm that randomly chooses a pixel as a nucleoli pattern would detect five correct patterns in the first 100 ranked objects. Detection of sparse nucleoli patterns in a large background of highly variable tissue patterns is a difficult challenge our method has overcome. This study developed an accurate prominent nucleoli pattern detector with the potential to be used in the clinical settings.

  16. Automated image based prominent nucleoli detection

    Directory of Open Access Journals (Sweden)

    Choon K Yap

    2015-01-01

    Full Text Available Introduction: Nucleolar changes in cancer cells are one of the cytologic features important to the tumor pathologist in cancer assessments of tissue biopsies. However, inter-observer variability and the manual approach to this work hamper the accuracy of the assessment by pathologists. In this paper, we propose a computational method for prominent nucleoli pattern detection. Materials and Methods: Thirty-five hematoxylin and eosin stained images were acquired from prostate cancer, breast cancer, renal clear cell cancer and renal papillary cell cancer tissues. Prostate cancer images were used for the development of a computer-based automated prominent nucleoli pattern detector built on a cascade farm. An ensemble of approximately 1000 cascades was constructed by permuting different combinations of classifiers such as support vector machines, eXclusive component analysis, boosting, and logistic regression. The output of cascades was then combined using the RankBoost algorithm. The output of our prominent nucleoli pattern detector is a ranked set of detected image patches of patterns of prominent nucleoli. Results: The mean number of detected prominent nucleoli patterns in the top 100 ranked detected objects was 58 in the prostate cancer dataset, 68 in the breast cancer dataset, 86 in the renal clear cell cancer dataset, and 76 in the renal papillary cell cancer dataset. The proposed cascade farm performs twice as good as the use of a single cascade proposed in the seminal paper by Viola and Jones. For comparison, a naive algorithm that randomly chooses a pixel as a nucleoli pattern would detect five correct patterns in the first 100 ranked objects. Conclusions: Detection of sparse nucleoli patterns in a large background of highly variable tissue patterns is a difficult challenge our method has overcome. This study developed an accurate prominent nucleoli pattern detector with the potential to be used in the clinical settings.

  17. Quantification of feather structure, wettability and resistance to liquid penetration

    Science.gov (United States)

    Srinivasan, Siddarth; Chhatre, Shreerang S.; Guardado, Jesus O.; Park, Kyoo-Chul; Parker, Andrew R.; Rubner, Michael F.; McKinley, Gareth H.; Cohen, Robert E.

    2014-01-01

    Birds in the cormorant (Phalacrocoracidae) family dive tens of metres into water to prey on fish while entraining a thin layer of air (a plastron film) within the microstructures of their feathers. In addition, many species within the family spread their wings for long periods of time upon emerging from water. To investigate whether wetting and wing-spreading are related to feather structure, microscopy and photographic studies have previously been used to extract structural parameters for barbs and barbules. In this work, we describe a systematic methodology to characterize the quasi-hierarchical topography of bird feathers that is based on contact angle measurements using a set of polar and non-polar probing liquids. Contact angle measurements on dip-coated feathers of six aquatic bird species (including three from the Phalacrocoracidae family) are used to extract two distinguishing structural parameters, a dimensionless spacing ratio of the barbule (D*) and a characteristic length scale corresponding to the spacing of defect sites. The dimensionless spacing parameter can be used in conjunction with a model for the surface topography to enable us to predict a priori the apparent contact angles of water droplets on feathers as well as the water breakthrough pressure required for the disruption of the plastron on the feather barbules. The predicted values of breakthrough depths in water (1–4 m) are towards the lower end of typical diving depths for the aquatic bird species examined here, and therefore a representative feather is expected to be fully wetted in a typical deep dive. However, thermodynamic surface energy analysis based on a simple one-dimensional cylindrical model of the feathers using parameters extracted from the goniometric analysis reveals that for water droplets on feathers of all six species under consideration, the non-wetting ‘Cassie–Baxter’ composite state represents the global energy minimum of the system. By contrast, for other

  18. Quantification of feather structure, wettability and resistance to liquid penetration.

    Science.gov (United States)

    Srinivasan, Siddarth; Chhatre, Shreerang S; Guardado, Jesus O; Park, Kyoo-Chul; Parker, Andrew R; Rubner, Michael F; McKinley, Gareth H; Cohen, Robert E

    2014-07-06

    Birds in the cormorant (Phalacrocoracidae) family dive tens of metres into water to prey on fish while entraining a thin layer of air (a plastron film) within the microstructures of their feathers. In addition, many species within the family spread their wings for long periods of time upon emerging from water. To investigate whether wetting and wing-spreading are related to feather structure, microscopy and photographic studies have previously been used to extract structural parameters for barbs and barbules. In this work, we describe a systematic methodology to characterize the quasi-hierarchical topography of bird feathers that is based on contact angle measurements using a set of polar and non-polar probing liquids. Contact angle measurements on dip-coated feathers of six aquatic bird species (including three from the Phalacrocoracidae family) are used to extract two distinguishing structural parameters, a dimensionless spacing ratio of the barbule (D*) and a characteristic length scale corresponding to the spacing of defect sites. The dimensionless spacing parameter can be used in conjunction with a model for the surface topography to enable us to predict a priori the apparent contact angles of water droplets on feathers as well as the water breakthrough pressure required for the disruption of the plastron on the feather barbules. The predicted values of breakthrough depths in water (1-4 m) are towards the lower end of typical diving depths for the aquatic bird species examined here, and therefore a representative feather is expected to be fully wetted in a typical deep dive. However, thermodynamic surface energy analysis based on a simple one-dimensional cylindrical model of the feathers using parameters extracted from the goniometric analysis reveals that for water droplets on feathers of all six species under consideration, the non-wetting 'Cassie-Baxter' composite state represents the global energy minimum of the system. By contrast, for other wetting

  19. Analysis of severe feather pecking behavior in a high feather pecking selection line

    DEFF Research Database (Denmark)

    Labouriau, R; Kjaer, J B; Abreu, G C G

    2009-01-01

    Even though feather pecking (FP) in laying hens has been extensively studied, a good solution to prevent chickens from this behavior under commercial circumstances has not been found. Selection against FP behavior is possible, but for a more effective selection across different populations......, it is necessary to characterize the genetic mechanism associated with this behavior. In this study, we use a high FP selection line, which has been selected for 8 generations. We present evidence of the presence of a major dominant allele affecting the FP behavior by using an argument based on the presence...

  20. Magnetohydrodynamic interpretation of the motion of prominences

    International Nuclear Information System (INIS)

    Sakurai, Takashi

    1976-01-01

    We study three types of prominence eruptions, which we will call the arch type, the loop type, and the gigantic arch type, respectively, from their shapes. If we regard the prominence as a magnetic flux tube, the onset of its ascending motion can be interpreted as the motion due to the screw-mode instability, which is the most unstable mode of instabilities of a magnetofluid column (pinch). The growth rate of this mode is evaluated and is shown to be consistent with the time scale of the initial stage of the eruption. In order to study the nonlinear stage of the instability, we propose a method of numerical calculation based on a variational technique known as Ritz's method. The result shows that the characteristic motion of the arch-, loop-, and gigantic arch-type eruptions may be reproduced by perturbing a model sequence with decreasing pitch angles of the unperturbed helical magnetic field lines. This conclusion seems to be supported by the pitch angles of observed threads in each type of prominence and also by the fact that the observed time profiles of the rising velocity of the prominences of each type agree well with those predicted from model calculations. (auth.)

  1. Topic Prominence in Chinese EFL Learners' Interlanguage

    Science.gov (United States)

    Li, Shaopeng; Yang, Lianrui

    2014-01-01

    The present study aims to investigate the general characteristics of topicprominent typological interlanguage development of Chinese learners of English in terms of acquiring subject-prominent English structures from a discourse perspective. Topic structures mainly appear in Chinese discourse in the form of topic chains (Wang, 2002; 2004). The…

  2. PROMINENCE ACTIVATION BY CORONAL FAST MODE SHOCK

    Energy Technology Data Exchange (ETDEWEB)

    Takahashi, Takuya [Department of Astronomy, Kyoto University, Sakyo, Kyoto, 606-8502 (Japan); Asai, Ayumi [Unit of Synergetic Studies for Space, Kyoto University, Yamashina, Kyoto 607-8471 (Japan); Shibata, Kazunari, E-mail: takahashi@kwasan.kyoto-u.ac.jp [Kwasan and Hida Observatories, Kyoto University, Yamashina, Kyoto 607-8471 (Japan)

    2015-03-01

    An X5.4 class flare occurred in active region NOAA11429 on 2012 March 7. The flare was associated with a very fast coronal mass ejection (CME) with a velocity of over 2500 km s{sup −1}. In the images taken with the Solar Terrestrial Relations Observatory-B/COR1, a dome-like disturbance was seen to detach from an expanding CME bubble and propagated further. A Type-II radio burst was also observed at the same time. On the other hand, in extreme ultraviolet images obtained by the Solar Dynamic Observatory/Atmospheric Imaging Assembly (AIA), the expanding dome-like structure and its footprint propagating to the north were observed. The footprint propagated with an average speed of about 670 km s{sup −1} and hit a prominence located at the north pole and activated it. During the activation, the prominence was strongly brightened. On the basis of some observational evidence, we concluded that the footprint in AIA images and the ones in COR1 images are the same, that is, the MHD fast mode shock front. With the help of a linear theory, the fast mode Mach number of the coronal shock is estimated to be between 1.11 and 1.29 using the initial velocity of the activated prominence. Also, the plasma compression ratio of the shock is enhanced to be between 1.18 and 2.11 in the prominence material, which we consider to be the reason for the strong brightening of the activated prominence. The applicability of linear theory to the shock problem is tested with a nonlinear MHD simulation.

  3. Multispacecraft observations of a prominence eruption

    Directory of Open Access Journals (Sweden)

    A. Bemporad

    2009-10-01

    Full Text Available On 9 May 2007 a prominence eruption occurred at the West limb. Remarkably, the event was observed by the STEREO/EUVI telescopes and by the HINODE/EIS and SOHO/UVCS spectrometers. We present results from all these instruments. High-cadence (~37 s data from STEREO/EUVI A and B in the He II λ304 line were used to study the 3-D shape and expansion of the prominence. The high spatial resolution EUVI images (~1.5"/pixel have been used to infer via triangulation the 3-D shape and orientation of the prominence 12 min after the eruption onset. At this time the prominence has mainly the shape of a "hook" highly inclined southward, has an average thickness of 0.068 R⊙, a length of 0.43 R⊙ and lies, in first approximation, on a plane. Hence, the prominence is mainly a 2-D structure and there is no evidence for a twisted flux rope configuration. HINODE/EIS was scanning with the 2" slit the region where the filament erupted. The EIS spectra show during the eruption remarkable non-thermal broadening (up to ~100 km s−1 in the region crossed by the filament in spectral lines emitted at different temperatures, possibly with differences among lines from higher Fe ionization stages. The CME was also observed by the SOHO/UVCS instrument: the spectrograph slit was centered at 1.7 R⊙, at a latitude of 5° SW and recorded a sudden increase in the O VI λλ1032–1037 and Si XII λ520 spectral line intensities, representative of the CME front transit.

  4. Aesthetic Refinements in Patients with Prominent Eyes.

    Science.gov (United States)

    Richter, Dirk F; Schwaiger, Nina; Wiedner, Maria

    2015-12-01

    The treatment of prominent eyes is still a challenging task. As well as the surgery, proper preoperative diagnosis differentiating between patients with and without Graves ophthalmopathy plays an important role. In functionally asymptomatic patients with Graves disease suffering from the aesthetic impairment of prominent eyes, the transpalpebral decompression by intraorbital fat removal technique has been proved to be reliable, effective, safe, and easily performed by a trained and experienced oculoplastic surgeon. This technique provides long-lasting results, leading to improvement not only in visual function but also in personal well-being and in the patient's social life, with a high benefit-to-risk ratio. The most powerful tool to treat the lower lid deformity and malar bags in patients without Graves disease is the subperiosteal midface lift. It shortens the lid-cheek junction and blends the retaining periorbital ligaments. Furthermore, it adds volume to the lower lid and gives a stable support. By the nature of the procedure, it also turns a negative into a positive vector. In experienced hands, Olivari's orbital decompression and Hester's midface lift are ideal options for the treatment of prominent eyes. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

  5. Theoretical morphology and development of flight feather vane asymmetry with experimental tests in parrots.

    Science.gov (United States)

    Feo, Teresa J; Prum, Richard O

    2014-06-01

    Asymmetry in flight feather vane width is a major functional innovation associated with the evolution of flight in the ancestors of birds. However, the developmental and morphological basis of feather shape is not simple, and the developmental processes involved in vane width asymmetry are poorly understood. We present a theoretical model of feather morphology and development that describes the possible ways to modify feather development and produce vane asymmetry. Our model finds that the theoretical morphospace of feather shape is redundant, and that many different combinations of parameters could be responsible for vane asymmetry in a given feather. Next, we empirically measured morphological and developmental model parameters in asymmetric and symmetric feathers from two species of parrots to identify which combinations of parameters create vane asymmetry in real feathers. We found that both longer barbs, and larger barb angles in the relatively wider trailing vane drove asymmetry in tail feathers. Developmentally, longer barbs were the result of an offset of the radial position of the new barb locus, whereas larger barb angles were produced by differential expansion of barbs as the feather unfurls from the tubular feather germ. In contrast, the helical angle of barb ridge development did not contribute to vane asymmetry and could be indicative of a constraint. This research provides the first comprehensive description of both the morphological and developmental modifications responsible for vane asymmetry within real feathers, and identifies key steps that must have occurred during the evolution of vane asymmetry. © 2014 Wiley Periodicals, Inc.

  6. The development and causation of feather pecking in the domestic fowl

    NARCIS (Netherlands)

    Blokhuis, H.J.

    1989-01-01

    Feather pecking in poultry consists of pecking directed at the feathers of other birds, sometimes pulling out and eating these feathers. It may result in severe damage of the integument of the birds, including wounds of the skin. Finally wounded birds may be pecked to death (cannibalism).

  7. 77 FR 12493 - Revisions to the California State Implementation Plan, Feather River Air Quality Management District

    Science.gov (United States)

    2012-03-01

    ... the California State Implementation Plan, Feather River Air Quality Management District AGENCY... limited disapproval of revisions to the Feather River Air Quality Management District (FRAQMD) portion of.... * * * * * (c) * * * (378) * * * (i) * * * (E) Feather River Air Quality Management District. (1) Rule 3.22...

  8. Do spotless starlings place feathers at their nests by ultraviolet color?

    Science.gov (United States)

    Avilés, Jesús M.; Parejo, Deseada; Pérez-Contreras, Tomás; Navarro, Carlos; Soler, Juan J.

    2010-02-01

    A considerable number of bird species carry feathers to their nests. Feathers’ presence in the nests has traditionally been explained by their insulating properties. Recently, however, it has been suggested that feathers carried to the nests by females of the spotted starling ( Sturnus unicolor L.) could have an ornamental function based on their ultraviolet (300-400 nm) and human-visible longer wavelength (400-700 nm) coloration. In our population, 95.7% of feathers found inside next-boxes occupied by nesting starlings were rock dove fly feathers. Of these feathers, 82.7% were naturally positioned with their reverse side oriented toward the entrance hole and 42.4% of all found feathers were situated within the nest-cup. Here we experimentally assess the signaling function of ultraviolet coloration of feathers in nests of spotless starlings by providing nests with a number of pigeon flight feathers that were respectively treated on their obverse, reverse, both, or neither side with a UV blocker. Starlings placed 42.5% of the experimental feathers in the nest-cup irrespective of the UV block treatment. Orientation of feathers toward the entrance hole was not related with their ultraviolet radiation. However, feathers placed within the nest-cup were more likely found with their reverse side oriented toward the entrance hole confirming our correlative findings. These results suggest a minor role of ultraviolet coloration on feather location by spotless starlings.

  9. parasitised feathered dinosaurs as revealed by Cretaceous amber assemblages.

    Science.gov (United States)

    Peñalver, Enrique; Arillo, Antonio; Delclòs, Xavier; Peris, David; Grimaldi, David A; Anderson, Scott R; Nascimbene, Paul C; Pérez-de la Fuente, Ricardo

    2017-12-12

    Ticks are currently among the most prevalent blood-feeding ectoparasites, but their feeding habits and hosts in deep time have long remained speculative. Here, we report direct and indirect evidence in 99 million-year-old Cretaceous amber showing that hard ticks and ticks of the extinct new family Deinocrotonidae fed on blood from feathered dinosaurs, non-avialan or avialan excluding crown-group birds. A †Cornupalpatum burmanicum hard tick is entangled in a pennaceous feather. Two deinocrotonids described as †Deinocroton draculi gen. et sp. nov. have specialised setae from dermestid beetle larvae (hastisetae) attached to their bodies, likely indicating cohabitation in a feathered dinosaur nest. A third conspecific specimen is blood-engorged, its anatomical features suggesting that deinocrotonids fed rapidly to engorgement and had multiple gonotrophic cycles. These findings provide insight into early tick evolution and ecology, and shed light on poorly known arthropod-vertebrate interactions and potential disease transmission during the Mesozoic.

  10. Determination of Cr and Cd concentration adsorbed by chicken feathers

    International Nuclear Information System (INIS)

    Lopez M, A.; Cuapio O, L.A.; Cardenas P, S.; Balcazar, M.; Jauregui, V.; Bonilla P, A.

    2008-01-01

    In this work the results of the samples analysis of chicken feathers are presented, used as adsorber of the heavy metals Cd and Cr present in water solutions with well-known concentrations of these metals. It was used the Neutron Activation Analysis technique (AAN), using the TRIGA Mark-III reactor of the Nuclear Center of Mexico. The obtained results they show the advantages of having a versatile installation for the analysis of this type of samples. By means of the analysis of the results, it was determined the feasibility of using chicken feathers like adsorber of these metals present in polluted waters, additionally, it was detected the presence of others polluting elements in the inputs to prepare the reference solutions as well as in the processes, so much of preparation of the feathers like of the metals adsorption. (Author)

  11. Tyrannosauroid integument reveals conflicting patterns of gigantism and feather evolution.

    Science.gov (United States)

    Bell, Phil R; Campione, Nicolás E; Persons, W Scott; Currie, Philip J; Larson, Peter L; Tanke, Darren H; Bakker, Robert T

    2017-06-01

    Recent evidence for feathers in theropods has led to speculations that the largest tyrannosaurids, including Tyrannosaurus rex , were extensively feathered. We describe fossil integument from Tyrannosaurus and other tyrannosaurids ( Albertosaurus, Daspletosaurus, Gorgosaurus and Tarbosaurus ), confirming that these large-bodied forms possessed scaly, reptilian-like skin. Body size evolution in tyrannosauroids reveals two independent occurrences of gigantism; specifically, the large sizes in Yutyrannus and tyrannosaurids were independently derived. These new findings demonstrate that extensive feather coverings observed in some early tyrannosauroids were lost by the Albian, basal to Tyrannosauridae. This loss is unrelated to palaeoclimate but possibly tied to the evolution of gigantism, although other mechanisms exist. © 2017 The Author(s).

  12. Morphology of primary feathers in two falcon species

    Science.gov (United States)

    Honisch, B.; Bleckmann, H.; Schmitz, H.; Schmitz, A.

    2012-04-01

    Primary feathers allow birds to fly; however, morphology and material properties of theses feathers vary in different bird species. We therefore analysed both morphology and material properties of primary feathers in two raptor species, the peregrine falcon (Falco peregrinus) which is the fastest vertical flyer known, and the kestrel (Falco tinnunculus), using scanning electron microscopy (SEM) and nanoindentation. The program AutoCAD was used for the computation of the moments of inertia. The reduced E-modulus of the cortex of the rachis of the first, fifth, and tenth primary were measured at proximal (10% of total rachis length), central (50%) and distal (75%) cross-sections. In all cross sections the kestrel showed higher E-moduli than the peregrine falcon (values varied between 6.7 and 9.1 GPa). In the primaries, values increased from proximal to central but decreased distally. Looking at the hardness, the kestrel had higher values than the peregrine falcon yet again. The main differences occurred in the first primary. Values ranged between 0.17 and 0.4 GPa. SEM studies revealed that the tenth primary was more stable in the peregrine falcon, featuring more hamuli than the kestrel at all analysed positions and longer hamuli at the distal positions. The higher moments of inertia found in the peregrine falcon caused a much higher bending stiffness in this species. Values were 4.4 to 9.1 times larger in the peregrine falcon than in the kestrel. Because the given structures are responsible for the stability of the feather face it seems that the feathers of F. peregrinus are more robust than those of F. tinnunculus. Even when considering the higher body mass of the peregrine falcon compared to the kestrel (3.4 times), the determined stability of the feather compensates for this problem.

  13. Linking the molecular evolution of avian beta (β) keratins to the evolution of feathers.

    Science.gov (United States)

    Greenwold, Matthew J; Sawyer, Roger H

    2011-12-15

    Feathers of today's birds are constructed of beta (β)-keratins, structural proteins of the epidermis that are found solely in reptiles and birds. Discoveries of "feathered dinosaurs" continue to stimulate interest in the evolutionary origin of feathers, but few studies have attempted to link the molecular evolution of their major structural proteins (β-keratins) to the appearance of feathers in the fossil record. Using molecular dating methods, we show that before the appearance of Anchiornis (∼155 Million years ago (Ma)) the basal β-keratins of birds began diverging from their archosaurian ancestor ∼216 Ma. However, the subfamily of feather β-keratins, as found in living birds, did not begin diverging until ∼143 Ma. Thus, the pennaceous feathers on Anchiornis, while being constructed of avian β-keratins, most likely did not contain the feather β-keratins found in the feathers of modern birds. Our results demonstrate that the evolutionary origin of feathers does not coincide with the molecular evolution of the feather β-keratins found in modern birds. More likely, during the Late Jurassic, the epidermal structures that appeared on organisms in the lineage leading to birds, including early forms of feathers, were constructed of avian β-keratins other than those found in the feathers of modern birds. Recent biophysical studies of the β-keratins in feathers support the view that the appearance of the subfamily of feather β-keratins altered the biophysical nature of the feather establishing its role in powered flight. Copyright © 2011 Wiley Periodicals, Inc., A Wiley Company.

  14. LARGE-SCALE FLOWS IN PROMINENCE CAVITIES

    International Nuclear Information System (INIS)

    Schmit, D. J.; Gibson, S. E.; Tomczyk, S.; Reeves, K. K.; Sterling, Alphonse C.; Brooks, D. H.; Williams, D. R.; Tripathi, D.

    2009-01-01

    Regions of rarefied density often form cavities above quiescent prominences. We observed two different cavities with the Coronal Multichannel Polarimeter on 2005 April 21 and with Hinode/EIS on 2008 November 8. Inside both of these cavities, we find coherent velocity structures based on spectral Doppler shifts. These flows have speeds of 5-10 km s -1 , occur over length scales of tens of megameters, and persist for at least 1 hr. Flows in cavities are an example of the nonstatic nature of quiescent structures in the solar atmosphere.

  15. Both feather peckers and victims are more asymmetrical than control hens

    DEFF Research Database (Denmark)

    Machado Tahamtani, Fernanda; Forkman, Björn; Hinrichsen, Lena Karina

    2017-01-01

    Feather pecking is the major welfare issue facing the egg farming industry worldwide. Previous research has found a relationship between cannibalistic behaviour, fluctuating asymmetry of bilateral traits (FA) and body weight in laying hens. As cannibalism is linked to severe feather pecking......, it could be suggested that a relationship between feather pecking, FA and body weight also exists. The purpose of this study was to analyse the association between feather pecking behaviour and a) FA, b) body weight and c) comb size in laying hens. Sixty-four laying hens were categorised as feather peckers...

  16. Hydrogen line formation in the quescent prominences

    International Nuclear Information System (INIS)

    Tsovookhuu, Ch.

    1980-01-01

    Equations of transfer and statistical equilibrium for hydronen atom with eight bound levels and continuum are solved simultaneously. A plane-parallel layer located perpendicular to the Sun surface is taken as a geometrical model. Input parameters of the physical model are optical thickness in the center of Hsub(α) line, electron temperature and concentration in the layer center are well as temperature and density gradients. Functions of sources, line profiles, total energies and the Balmer decrements, which are compared with observations and theoretical calculations made by other authors, have been calculated. The comparison shows that the results are quite acceptable and can be used when analyzing the spectrum and determining physical parameters of solar prominences. Dependence of different performances of the line (equivalent width, central intensity, halfwidth, depth of central depression etc.) on values of initial model parameters is investigated. Line halfwidth is more sensitive to the temperatuu value in the layer center, while central intensity - to the value of temperature gradient and a depth of central depression - to electron concentration. Calculated were shares of primary sources responsible for different excitation mechanism depending on total optical thickness as well as mean probabilities of quantum yield out of a medium which can be used during parametric accountancy of radiation diffusion in solar prominences [ru

  17. Ecomorphology of parasite attachment: experiments with feather lice.

    Science.gov (United States)

    Bush, Sarah E; Sohn, Edward; Clayton, Dale H

    2006-02-01

    The host specificity of some parasites can be reinforced by morphological specialization for attachment to mobile hosts. For example, ectoparasites with adaptations for attaching to hosts of a particular size might not be able to remain attached to larger or smaller hosts. This hypothesis is suggested by the positive correlation documented between the body sizes of many parasites and their hosts. We adopted an ecomorphological approach to test the attachment hypothesis. We tested the ability of host-specific feather lice (Phthiraptera: Ischnocera) to attach to 6 novel species of pigeons and doves that vary in size by nearly 2 orders of magnitude. Surprisingly, Rock Pigeon lice (Columbicola columbae) remained attached equally well to all 6 novel host species. We tested the relative importance of 3 factors that could facilitate louse attachment: whole-body insertion, tarsal claw use, and mandible use. Insertion, per se, was not necessary for attachment. However, insertion on coarse feathers of large hosts allowed lice to access feather barbules with their mandibles. Mandible use was a key component of attachment regardless of feather size. Attachment constraints do not appear to reinforce host specificity in this system.

  18. 50 CFR 20.91 - Commercial use of feathers.

    Science.gov (United States)

    2010-10-01

    ... 50 Wildlife and Fisheries 6 2010-10-01 2010-10-01 false Commercial use of feathers. 20.91 Section 20.91 Wildlife and Fisheries UNITED STATES FISH AND WILDLIFE SERVICE, DEPARTMENT OF THE INTERIOR.... Any person may possess, purchase, sell, barter, or transport for the making of fishing flies, bed...

  19. Modelling growth curves of Nigerian indigenous normal feather ...

    African Journals Online (AJOL)

    This study was conducted to predict the growth curve parameters using Bayesian Gompertz and logistic models and also to compare the two growth function in describing the body weight changes across age in Nigerian indigenous normal feather chicken. Each chick was wing-tagged at day old and body weights were ...

  20. Mercury bioaccumulation in Southern Appalachian birds, assessed through feather concentrations

    Science.gov (United States)

    Rebecca Hylton Keller; Lingtian Xie; David B. Buchwalter; Kathleen E. Franzreb; Theodore R Simons

    2014-01-01

    Mercury contamination in wildlife has rarely been studied in the Southern Appalachians despite high deposition rates in the region. From 2006 to 2008 we sampled feathers from 458 birds representing 32 species in the Southern Appalachians for total mercury and stable isotope ä 15N. Mercury concentrations (mean ± SE) averaged 0.46...

  1. Preparation and characterization of sponge film made from feathers

    Energy Technology Data Exchange (ETDEWEB)

    Zhuang, Yuan; Wu, Xiaoqian [College of Environmental Science and Engineering, Donghua University, Shanghai 201620 (China); Cao, Zhangjun [College of Chemistry, Chemical Engineering and Biotechnology, Donghua University, Shanghai 201620 (China); Zhao, Xiaoxiang; Zhou, Meihua [College of Environmental Science and Engineering, Donghua University, Shanghai 201620 (China); Gao, Pin, E-mail: gaopin@mail.dhu.edu.cn [College of Environmental Science and Engineering, Donghua University, Shanghai 201620 (China)

    2013-12-01

    Feather wastes generated from poultry farms will pose a problem for disposal, but they are sustainable resources of keratin. Reduction is one of the commonly used methods to obtain soluble keratin from feather. However, the residues generated during feather reduction reaction were rarely investigated. In this study, the residues were transformed into a porous and flexible sponge film by freeze-drying without pretreatment or addition of cross-linking agents. Glycerol was used to alter the physical and chemical characteristics of the sponge film. The film was characterized with a fiber strong stretch instrument, a Fourier transform infrared spectrophotometer, scanning electron microscopy, an elemental analyzer, a differential scanning calorimeter and an automatic air permeability apparatus. Tensile strength and melting point of the sponge film with the optimum glycerol content were 6.2 MPa and 170 °C respectively. Due to air permeability of 368 mm/s, the film can potentially be used in medicine, biology, textile, environmental technology, and so on. It is ecologically friendly and will produce additional benefits from the renewable materials. The film was utilized as adsorbents to remove Cr(VI) from aqueous solutions and as a filtering material for air pollution. Its maximum Cr(VI) uptake capacity was about 148.8 mg/g and the removal rate of PM{sub 10} was 98.3%. - Graphical abstract: The reduction residues were made into a smooth, elastic, porous and flexible sponge film through freeze drying, no pretreatment and no cross-linking agent added. - Highlights: • The residue from feather waste reduction was turned into a sponge film. • A glycerol content of 5% produced a sponge with the optimum characteristics. • The sponge was uniform, stable up to 160 °C, and had an air permeability of 368 mm/s. • Feather-derived sponge film has potential applications in medicine and technology.

  2. Preparation and characterization of sponge film made from feathers

    International Nuclear Information System (INIS)

    Zhuang, Yuan; Wu, Xiaoqian; Cao, Zhangjun; Zhao, Xiaoxiang; Zhou, Meihua; Gao, Pin

    2013-01-01

    Feather wastes generated from poultry farms will pose a problem for disposal, but they are sustainable resources of keratin. Reduction is one of the commonly used methods to obtain soluble keratin from feather. However, the residues generated during feather reduction reaction were rarely investigated. In this study, the residues were transformed into a porous and flexible sponge film by freeze-drying without pretreatment or addition of cross-linking agents. Glycerol was used to alter the physical and chemical characteristics of the sponge film. The film was characterized with a fiber strong stretch instrument, a Fourier transform infrared spectrophotometer, scanning electron microscopy, an elemental analyzer, a differential scanning calorimeter and an automatic air permeability apparatus. Tensile strength and melting point of the sponge film with the optimum glycerol content were 6.2 MPa and 170 °C respectively. Due to air permeability of 368 mm/s, the film can potentially be used in medicine, biology, textile, environmental technology, and so on. It is ecologically friendly and will produce additional benefits from the renewable materials. The film was utilized as adsorbents to remove Cr(VI) from aqueous solutions and as a filtering material for air pollution. Its maximum Cr(VI) uptake capacity was about 148.8 mg/g and the removal rate of PM 10 was 98.3%. - Graphical abstract: The reduction residues were made into a smooth, elastic, porous and flexible sponge film through freeze drying, no pretreatment and no cross-linking agent added. - Highlights: • The residue from feather waste reduction was turned into a sponge film. • A glycerol content of 5% produced a sponge with the optimum characteristics. • The sponge was uniform, stable up to 160 °C, and had an air permeability of 368 mm/s. • Feather-derived sponge film has potential applications in medicine and technology

  3. Flotation process control optimisation at Prominent Hill

    International Nuclear Information System (INIS)

    Lombardi, Josephine; Muhamad, Nur; Weidenbach, M.

    2012-01-01

    OZ Minerals' Prominent Hill copper- gold concentrator is located 130 km south east of the town of Coober Pedy in the Gawler Craton of South Australia. The concentrator was built in 2008 and commenced commercial production in early 2009. The Prominent Hill concentrator is comprised of a conventional grinding and flotation processing plant with a 9.6 Mtpa ore throughput capacity. The flotation circuit includes six rougher cells, an IseMill for regrinding the rougher concentrate and a Jameson cell heading up the three stage conventional cell cleaner circuit. In total there are four level controllers in the rougher train and ten level controllers in the cleaning circuit for 18 cells. Generic proportional — integral and derivative (PID) control used on the level controllers alone propagated any disturbances downstream in the circuit that were generated from the grinding circuit, hoppers, between cells and interconnected banks of cells, having a negative impact on plant performance. To better control such disturbances, FloatStar level stabiliser was selected for installation on the flotation circuit to account for the interaction between the cells. Multivariable control was also installed on the five concentrate hoppers to maintain consistent feed to the cells and to the IsaMill. An additional area identified for optimisation in the flotation circuit was the mass pull rate from the rougher cells. FloatStar flow optimiser was selected to be installed subsequent to the FloatStar level stabiliser. This allowed for a unified, consistent and optimal approach to running the rougher circuit. This paper describes the improvement in the stabilisation of the circuit achieved by the FloatStar level stabiliser by using the interaction matrix between cell level controllers and the results and benefits of implementing the FloatStar flow optimiser on the rougher train.

  4. Holding tight on feathers - structural specializations and attachment properties of the avian ectoparasite Crataerina pallida (Diptera, Hippoboscidae).

    Science.gov (United States)

    Petersen, Dennis S; Kreuter, Nils; Heepe, Lars; Büsse, Sebastian; Wellbrock, Arndt H J; Witte, Klaudia; Gorb, Stanislav N

    2018-04-30

    The louse fly Crataerina pallida is an obligate blood-sucking ecto-parasite of the common swift Apus apus Due to reduction of the wings, C. pallida is unable to fly, thus an effective and reliable attachment to their host's plumage is of outmost importance. Its attachment system shows several modifications in comparison to other calyptrate flies. The most prominent ones are the large tridentate claws and the dichotomously shaped setae located on the pulvilli. Based on data from morphological analysis, confocal laser scanning microscopy, cryo-scanning electron microscopy and traction force experiments, performed on native (feathers) as well as artificial substrates (glass, epoxy-resin and silicone rubber), we showed that the entire attachment system is highly adapted to the fly's lifestyle as an ectoparasite. The claws in particular are the main contributor to strong attachment to the host. Resulting attachment forces on feathers make it impossible to detach C. pallida without damage of feathers or legs of the fly itself. Well-developed pulvilli are responsible for the attachment to smooth surfaces. Both dichotomously shaped setae and high setal density explain high safety factors observed on smooth substrates. For the first time, we demonstrated a material gradient within the setae with soft, resilin dominated apical tips and stiff, more sclerotized bases in Diptera. The empodium seems not to be directly involved in the attachment process, but it might operate as a cleaning device and may be essential to maintain the functionality of the entire attachment system. © 2018. Published by The Company of Biologists Ltd.

  5. Adrenocortical reactivity and central serotonin and dopamine turnover in young chicks from a high and low feather-pecking line of laying hens

    NARCIS (Netherlands)

    van Hierden, YM; Korte, SM; Ruesink, EW; van Reenen, CG; Engel, B; Korte-Bouws, GAH; Koolhaas, JM; Blokhuis, HJ

    2002-01-01

    Feather pecking in domestic fowl is a behavioral abnormality that consists of mild or injurious pecking at feathers of conspecifics. Previously, it was shown that chicks from a high feather-pecking (HFP) and low feather-pecking (LFP) line of laying hens already differ in their propensity to feather

  6. The Computational Processing of Intonational Prominence: A Functional Prosody Perspective

    OpenAIRE

    Nakatani, Christine Hisayo

    1997-01-01

    Intonational prominence, or accent, is a fundamental prosodic feature that is said to contribute to discourse meaning. This thesis outlines a new, computational theory of the discourse interpretation of prominence, from a FUNCTIONAL PROSODY perspective. Functional prosody makes the following two important assumptions: first, there is an aspect of prominence interpretation that centrally concerns discourse processes, namely the discourse focusing nature of prominence; and second, the role of p...

  7. Manakins can produce iridescent and bright feather colours without melanosomes.

    Science.gov (United States)

    Igic, Branislav; D'Alba, Liliana; Shawkey, Matthew D

    2016-06-15

    Males of many species often use colourful and conspicuous ornaments to attract females. Among these, male manakins (family: Pipridae) provide classic examples of sexual selection favouring the evolution of bright and colourful plumage coloration. The highly iridescent feather colours of birds are most commonly produced by the periodic arrangement of melanin-containing organelles (melanosomes) within barbules. Melanin increases the saturation of iridescent colours seen from optimal viewing angles by absorbing back-scattered light; however, this may reduce the wide-angle brightness of these signals, contributing to a dark background appearance. We examined the nanostructure of four manakin species (Lepidothrix isidorei, L. iris, L. nattereri and L. coeruleocapilla) to identify how they produce their bright plumage colours. Feather barbs of all four species were characterized by dense and fibrous internal spongy matrices that likely increase scattering of light within the barb. The iridescent, yet pale or whitish colours of L. iris and L. nattereri feathers were produced not by periodically arranged melanosomes within barbules, but by periodic matrices of air and β-keratin within barbs. Lepidothrix iris crown feathers were able to produce a dazzling display of colours with small shifts in viewing geometry, likely because of a periodic nanostructure, a flattened barb morphology and disorder at a microstructural level. We hypothesize that iridescent plumage ornaments of male L. iris and L. nattereri are under selection to increase brightness or luminance across wide viewing angles, which may potentially increase their detectability by females during dynamic and fast-paced courtship displays in dim light environments. © 2016. Published by The Company of Biologists Ltd.

  8. Feather mites of Calidris fuscicollis (Aves: Scolopacidae) in Brazil

    OpenAIRE

    Gomes, S. N.; Pesenti, T. C.; Cirne, M. P.; Müller, G.

    2015-01-01

    Abstract During the period 2010-2012, eighty individuals of Calidris fuscicollis (Vieillot, 1819) were collected on the southern coast of Rio Grande do Sul, Brazil, with the objective of determining the presence of feather mites. Of the 80 birds examined, 32.5% were infested by mites, identified as Avenzoaria calidridis (Oudemans, 1904) (Avenzoariidae) (31.25%), Montchadskiana securicata (Megnin & Trouessart 1884) (Pterolichidae) (22.5%) and Alloptes limosae (Dubinin, 1951) (Alloptidae) (6.25...

  9. Fully Biodegradable Biocomposites with High Chicken Feather Content

    OpenAIRE

    Aranberri, Ibon; Montes, Sarah; Azcune, Itxaso; Rekondo, Alaitz; Grande, Hans-Jürgen

    2017-01-01

    The aim of this work was to develop new biodegradable polymeric materials with high loadings of chicken feather (CF). In this study, the effect of CF concentration and the type of biodegradable matrix on the physical, mechanical and thermal properties of the biocomposites was investigated. The selected biopolymers were polylactic acid (PLA), polybutyrate adipate terephthalate (PBAT) and a PLA/thermoplastic copolyester blend. The studied biocomposites were manufactured with a to...

  10. Chicken feather fiber as an additive in MDF composites

    Science.gov (United States)

    Jerrold E. Winandy; James H. Muehl; Jessie A. Glaeser; Walter Schmidt

    2007-01-01

    Medium density fiberboard (MDF) panels were made with aspen fiber and 0-95% chicken feather fiber (CFF) in 2.5%, 5%, or 25% increments, using 5% phenol formaldehyde resin as the adhesive. Panels were tested for mechanical and physical properties as well as decay. The addition of CFF decreased strength and stiffness of MDF-CFF composites compared with that of all-wood...

  11. Poultry feather wastes recycling possibility as soil nutrient

    Directory of Open Access Journals (Sweden)

    Lili Mézes

    2015-10-01

    Full Text Available Poultry feathers are produced in large amounts as a waste in poultry slaughterhouses. Only 60-70% of the poultry slaughterhouse products are edible for human being. This means more million tons annually worldwide (Papadopoulus et al., 1986; Williams et al., 1991; Hegedűs et al., 1998. The keratin-content of feather can be difficulty digested, so physical, chemical and/or biological pre-treatment are needed in practice, which have to be set according to the utilization method. Feather was enzymatic degraded, and then fermented in separated bioreactors. The anaerobic bioreactor system (4 digesters with 6 litre volume was controlled by ACE SCADA software running on Linux platforms. Pot scale seed germination tests were established to suggest the quantity of digested slurry to be utilized. The chosen test plants were lettuce (Lactuca sativa. In case of reproduction test Student’s t-test was applied to examine significant differences between the root lengths of the control and the treated plant species. In case of pot seed germination variance analysis with Tukey B’s and Duncan test was applied to examine significant differences between the root lengths of plants, grown on different treatments. The effect of treatments on germination ability of the plant species was expressed in the percentage of the controls. According to Student’s t-test significant difference was found between root lengths of different treatments. Based on variance analysis with Tukey B’s and Duncan tests could be detected a significant difference between the treatments. Utilization of the fermented material reduces the use of fertilizers and because of its large moisture content it reduces the watering costs. Recycle of the slaughterhouse feather and different agricultural wastes and by-products can solve three main problems: disposal of harmful materials, producing of renewable energy and soil nutrient, measuring reflectance at the certain spectral range, which can

  12. Study of chemisrty and hydrolysates drying parameters of feather-downy raw material

    OpenAIRE

    LISITSYN A.B.; KRIGER O.V.; MITROKHIN P.V.

    2016-01-01

    The article describes chemical and amino acid composition of feather-downy raw material. It determines the mass fraction of crude protein, crude fiber, ash, calcium, phosphorus, sodium in the samples of feather-downy raw material. It is stated that the waste from poultry processing obtained from hens of all the studied species are characterized by a high content of crude protein and low in crude fiber and ash. The most valuable feather-downy raw material regarding protein is waste containing ...

  13. Shrimp pond wastewater treatment using pyrolyzed chicken feather as adsorbent

    Science.gov (United States)

    Moon, Wei Chek; Jbara, Mohamad Hasan; Palaniandy, Puganeshwary; Yusoff, Mohd Suffian

    2017-10-01

    In this study, chicken feather fiber was used as a raw material to prepare a non-expensive adsorbent by pyrolysis without chemical activation. The main pollutants treated in this study were chemical oxygen demand (COD) and ammoniacal nitrogen (NH3-N) from shrimp pond wastewater containing high concentrations of nutrients, which caused the eutrophication phenomenon in adjacent water. Batch adsorption studies were performed to investigate the effect of pH (5-8), mass of adsorbent (0.5-3 g), and shaking time (0.5-2 h) on the removal efficiency of COD and NH3- N. Experimental results showed that the optimum conditions were as follows: pH 5, 0.5 g of adsorbent, and 0.5 h of shaking. Under these conditions, 34.01% and 40.47% of COD and NH3-N were removed, respectively, from shrimp pond wastewater. The adsorption processes were best described by the Langmuir isotherm model for COD and NH3-N removal, with maximum monolayer adsorption capacity of 36.9 and 7.24 mg/g for COD and NH3-N, respectively. The results proved that chicken feather could remove COD and NH3-N from shrimp pond wastewater. However, further studies on thermal treatment should be carried out to increase the removal efficiency of pyrolyzed chicken feather fiber.

  14. Fully Biodegradable Biocomposites with High Chicken Feather Content

    Directory of Open Access Journals (Sweden)

    Ibon Aranberri

    2017-11-01

    Full Text Available The aim of this work was to develop new biodegradable polymeric materials with high loadings of chicken feather (CF. In this study, the effect of CF concentration and the type of biodegradable matrix on the physical, mechanical and thermal properties of the biocomposites was investigated. The selected biopolymers were polylactic acid (PLA, polybutyrate adipate terephthalate (PBAT and a PLA/thermoplastic copolyester blend. The studied biocomposites were manufactured with a torque rheometer having a CF content of 50 and 60 wt %. Due to the low tensile strength of CFs, the resulting materials were penalized in terms of mechanical properties. However, high-loading CF biocomposites resulted in lightweight and thermal-insulating materials when compared with neat bioplastics. Additionally, the adhesion between CFs and the PLA matrix was also investigated and a significant improvement of the wettability of the feathers was obtained with the alkali treatment of the CFs and the addition of a plasticizer like polyethylene glycol (PEG. Considering all the properties, these 100% fully biodegradable biocomposites could be adequate for panel components, flooring or building materials as an alternative to wood–plastic composites, contributing to the valorisation of chicken feather waste as a renewable material.

  15. Melanosome evolution indicates a key physiological shift within feathered dinosaurs.

    Science.gov (United States)

    Li, Quanguo; Clarke, Julia A; Gao, Ke-Qin; Zhou, Chang-Fu; Meng, Qingjin; Li, Daliang; D'Alba, Liliana; Shawkey, Matthew D

    2014-03-20

    Inference of colour patterning in extinct dinosaurs has been based on the relationship between the morphology of melanin-containing organelles (melanosomes) and colour in extant bird feathers. When this relationship evolved relative to the origin of feathers and other novel integumentary structures, such as hair and filamentous body covering in extinct archosaurs, has not been evaluated. Here we sample melanosomes from the integument of 181 extant amniote taxa and 13 lizard, turtle, dinosaur and pterosaur fossils from the Upper-Jurassic and Lower-Cretaceous of China. We find that in the lineage leading to birds, the observed increase in the diversity of melanosome morphologies appears abruptly, near the origin of pinnate feathers in maniraptoran dinosaurs. Similarly, mammals show an increased diversity of melanosome form compared to all ectothermic amniotes. In these two clades, mammals and maniraptoran dinosaurs including birds, melanosome form and colour are linked and colour reconstruction may be possible. By contrast, melanosomes in lizard, turtle and crocodilian skin, as well as the archosaurian filamentous body coverings (dinosaur 'protofeathers' and pterosaur 'pycnofibres'), show a limited diversity of form that is uncorrelated with colour in extant taxa. These patterns may be explained by convergent changes in the key melanocortin system of mammals and birds, which is known to affect pleiotropically both melanin-based colouration and energetic processes such as metabolic rate in vertebrates, and may therefore support a significant physiological shift in maniraptoran dinosaurs.

  16. Preparation and characterization of sponge film made from feathers.

    Science.gov (United States)

    Zhuang, Yuan; Wu, Xiaoqian; Cao, Zhangjun; Zhao, Xiaoxiang; Zhou, Meihua; Gao, Pin

    2013-12-01

    Feather wastes generated from poultry farms will pose a problem for disposal, but they are sustainable resources of keratin. Reduction is one of the commonly used methods to obtain soluble keratin from feather. However, the residues generated during feather reduction reaction were rarely investigated. In this study, the residues were transformed into a porous and flexible sponge film by freeze-drying without pretreatment or addition of cross-linking agents. Glycerol was used to alter the physical and chemical characteristics of the sponge film. The film was characterized with a fiber strong stretch instrument, a Fourier transform infrared spectrophotometer, scanning electron microscopy, an elemental analyzer, a differential scanning calorimeter and an automatic air permeability apparatus. Tensile strength and melting point of the sponge film with the optimum glycerol content were 6.2 MPa and 170°C respectively. Due to air permeability of 368 mm/s, the film can potentially be used in medicine, biology, textile, environmental technology, and so on. It is ecologically friendly and will produce additional benefits from the renewable materials. The film was utilized as adsorbents to remove Cr(VI) from aqueous solutions and as a filtering material for air pollution. Its maximum Cr(VI) uptake capacity was about 148.8 mg/g and the removal rate of PM10 was 98.3%. © 2013.

  17. Prominent Optic Disc Featured in Inherited Retinopathy.

    Science.gov (United States)

    Todorova, M G; Bojinova, R I; Valmaggia, C; Schorderet, D F

    2017-04-01

    Background We investigated the relationship between prominent optic disc (POD) and inherited retinal dystrophy (IRD). Patients and Methods A cross-sectional consecutive study was performed in 10 children and 11 adults of 7 non-related families. We performed clinical phenotyping, including a detailed examination, fundus autofluorescence, and colour fundus and OCT imaging. Genetic testing was subsequently performed for all family members presenting retinal pathology. Results In 4 members of a 3-generation family, hyperfluorescent deposits on the surface of POD were related to a p.(L224M) heterozygous mutation in BEST1 . In the second family, one member presented deposits located on the surface on hyperaemic OD and a compound p.(R141H);(A195V) mutation in BEST1 . In the third family, POD was observed in father and child with early onset cone-rod dystrophy and a novel autosomal recessive p.(W31*) homozygous mutation in ABCA4 . In the fourth family, POD with "mulberry-like" deposits and attenuated vessels were observed in a 7-year old girl, with a mutation in USH1A , and with early onset rod-cone dystrophy, associated with hearing loss. In the fifth family, blurry OD with tortuous vessels was observed in 4 consanguineous female carriers and a hemizygous boy with a p.(R200H) mutation in the X-linked retinoschisis RS1 . In the sixth family, a mother and her son were both affected with POD and attenuated peripapillary vessels, and presented with a p.(Y836C) heterozygous mutation in TOPORS , thus confirming autosomal dominant RP. In the seventh family, in 3 family members with POD, compound p.(L541P;A1038 V);(G1961E) mutations in ABCA4 confirmed the diagnosis of Stargardt disease. Conclusions A variety of OD findings are found in a genetically heterogeneous group of IRDs. In the presence of POD, an inherited progressive photoreceptor disease should be ruled out. Georg Thieme Verlag KG Stuttgart · New York.

  18. Polybrominated diphenyl ethers (PBDEs) in feathers of colonial water-bird species from Pakistan

    Energy Technology Data Exchange (ETDEWEB)

    Malik, Riffat Naseem, E-mail: r_n_malik2000@yahoo.co.uk [Environmental Biology Laboratory, Department of Plant Sciences, Faculty of Biological Sciences, Quaid-i-Azam University, Islamabad, PO 45320 (Pakistan); Moeckel, Claudia [Centre for Ecology and Hydrology, Lancaster Environment Centre, Library Avenue, Bailrigg, Lancaster LA1 4AP (United Kingdom); Jones, Kevin C.; Hughes, David [Centre for Chemicals Management, Lancaster Environment Centre, Lancaster University, Bailrigg, Lancaster LA1 4YQ (United Kingdom)

    2011-10-15

    Feathers of two colonial water-birds species (Bubulcus ibis, Egretta garzetta) from four heronries in the Punjab province, Pakistan were analysed for 28 Polybrominated Diphenyl Ethers (PBDEs) congeners. Median concentrations of {Sigma}PBDEs were 2.41 and 1.91 ng/g in little and cattle egrets. PBDE-47, -100, -138, -153 were abundant and detected in >70% of feather samples in both species. Species-specific differences based on dietary preferences indicated higher concentration of PBDE-47, -66, -75, -100, -153, -154, and -183 in fish eating little egret. BDE-47 and -100 were more frequent in little egrets and BDE-99 was more dominant in cattle egret which feed on terrestrial habitat. Higher {Sigma}hexa- and hepta-BDEs congeners showed larger concentrations in feathers from heronries close to water bodies which receive urban and industrial effluents whereas lower-brominated congeners (BDE-47-BDE-100) dominated in rural/agricultural regions. Hazard quotients (HQs) indicated that measured {Sigma}PBDEs pose no risk to egret population. - Highlights: > Feathers as non-destructive tool to asses Polybrominated Diphenyl Ethers (PBDEs) contamination. > PBDE-47 and -100 frequent in feathers of fish eating egrets. > BDE-99 dominant in feathers of egrets feed in terrestrial habitats. > Lower-brominated congeners (BDE-47-BDE-100) dominate in feathers from rural areas. > Greater contents of hexa- and hepta-BDEs in feathers from areas receive urban/industrial effluents. - Feathers are used as a biomonitoring tool for PBDEs contamination.

  19. Polybrominated diphenyl ethers (PBDEs) in feathers of colonial water-bird species from Pakistan

    International Nuclear Information System (INIS)

    Malik, Riffat Naseem; Moeckel, Claudia; Jones, Kevin C.; Hughes, David

    2011-01-01

    Feathers of two colonial water-birds species (Bubulcus ibis, Egretta garzetta) from four heronries in the Punjab province, Pakistan were analysed for 28 Polybrominated Diphenyl Ethers (PBDEs) congeners. Median concentrations of ΣPBDEs were 2.41 and 1.91 ng/g in little and cattle egrets. PBDE-47, -100, -138, -153 were abundant and detected in >70% of feather samples in both species. Species-specific differences based on dietary preferences indicated higher concentration of PBDE-47, -66, -75, -100, -153, -154, and -183 in fish eating little egret. BDE-47 and -100 were more frequent in little egrets and BDE-99 was more dominant in cattle egret which feed on terrestrial habitat. Higher Σhexa- and hepta-BDEs congeners showed larger concentrations in feathers from heronries close to water bodies which receive urban and industrial effluents whereas lower-brominated congeners (BDE-47-BDE-100) dominated in rural/agricultural regions. Hazard quotients (HQs) indicated that measured ΣPBDEs pose no risk to egret population. - Highlights: → Feathers as non-destructive tool to asses Polybrominated Diphenyl Ethers (PBDEs) contamination. → PBDE-47 and -100 frequent in feathers of fish eating egrets. → BDE-99 dominant in feathers of egrets feed in terrestrial habitats. → Lower-brominated congeners (BDE-47-BDE-100) dominate in feathers from rural areas. → Greater contents of hexa- and hepta-BDEs in feathers from areas receive urban/industrial effluents. - Feathers are used as a biomonitoring tool for PBDEs contamination.

  20. Melanin-based color of plumage: role of condition and of feathers' microstructure

    Science.gov (United States)

    D'Alba, Liliana; Van Hemert, Caroline R.; Spencer, Karen A.; Heidinger, Britt J.; Gill, Lisa; Evans, Neil P.; Monaghan, Pat; Handel, Colleen M.; Shawkey, Matthew D.

    2014-01-01

    Whether melanin-based colors honestly signal a bird's condition during the growth of feathers is controversial, and it is unclear if or how the physiological processes underlying melanogenesis or color-imparting structural feather microstructure may be adversely affected by condition. Here we report results from two experiments designed to measure the effect of condition on expression of eumelanic and pheomelanic coloration in black-capped chickadees (Poecile atricapillus) and zebra finches (Taeniopygia guttata), respectively. In chickadees, we compared feathers of birds affected and unaffected by avian keratin disorder, while in zebra finches we compared feathers of controls with feathers of those subjected to an unpredictable food supply during development. In both cases we found that control birds had brighter feathers (higher total reflectance) and more barbules, but similar densities of melanosomes. In addition, the microstructure of the feathers explained variation in color more strongly than did melanosome density. Together, these results suggest that melanin-based coloration may in part be condition-dependent, but that this may be driven by changes in keratin and feather development, rather than melanogenesis itself. Researchers should be cautious when assigning variation in melanin-based color to melanin alone and microstructure of the feather should be taken into account.

  1. Decreased hydrophobicity of iridescent feathers: a potential cost of shiny plumage.

    Science.gov (United States)

    Eliason, Chad M; Shawkey, Matthew D

    2011-07-01

    Honest advertisement models posit that sexually selected traits are costly to produce, maintain or otherwise bear. Brightly coloured feathers are thought to be classic examples of these models, but evidence for a cost in feathers not coloured by carotenoid pigments is scarce. Unlike pigment-based colours, iridescent feather colours are produced by light scattering in modified feather barbules that are characteristically flattened and twisted towards the feather surface. These modifications increase light reflectance, but also expose more surface area for water adhesion, suggesting a potential trade-off between colour and hydrophobicity. Using light microscopy, spectrometry, contact angle goniometry and self-cleaning experiments, we show that iridescent feathers of mallards, Anas platyrhynchos, are less hydrophobic than adjacent non-iridescent feathers, and that this is primarily caused by differences in barbule microstructure. Furthermore, as a result of this decreased hydrophobicity, iridescent feathers are less efficient at self-cleaning than non-iridescent feathers. Together, these results suggest a previously unforeseen cost of iridescent plumage traits that may help to explain the evolution and distribution of iridescence in birds.

  2. Adrenocortical reactivity and central serotonin and dopamine turnover in young chicks from a high and low feather-pecking line of laying hens

    OpenAIRE

    van Hierden, YM; Korte, SM; Ruesink, EW; van Reenen, CG; Engel, B; Korte-Bouws, GAH; Koolhaas, JM; Blokhuis, HJ

    2002-01-01

    Feather pecking in domestic fowl is a behavioral abnormality that consists of mild or injurious pecking at feathers of conspecifics. Previously, it was shown that chicks from a high feather-pecking (HFP) and low feather-pecking (LFP) line of laying hens already differ in their propensity to feather peck at 14 and 28 days of age. As a first step in investigating a possible relationship between the development of feather pecking and physiological and neurobiological characteristics of laying he...

  3. Signs of helicity in solar prominences and related features

    Science.gov (United States)

    Martin, S.

    This review illustrates several ways to identify the chirality (handedness) of solar prominences (filaments) from their structure and the structure of their surrounding magnetic fields in the chromosphere and corona. For prominences, these structural elements include the axial magnetic field direction, orientation of barbs, and direction of the prominence fine structure. The surrounding structures include the pattern of fibrils beneath the prominences and the pattern of coronal loops above the prominences. These ways of identifying chirality are then interpreted in terms of the formal definitions of helicity to yield a consistent set of one-to-one helicity relationships for all features. The helicity of some prominences can also be independently determined during their eruption by their fine structure, apparent crossings in the line-of-sight of different parts of the same prominence, and by large- scale twist of the prominence structure. Unlike observations of prominences (filaments) observed prior to eruption, in some cases evidence of both signs of helicity are found within the same erupting prominence. This indicates the continued application of forces on the prominences during the eruption process or the possible introduction of force(s) not present during earlier stages of their evolution.

  4. A three-dimensional model for solar prominences

    International Nuclear Information System (INIS)

    Demoulin, P.; Priest, E.R.; Anzer, U.

    1989-01-01

    Prominences have been modelled largely as one-or two-dimensional structures, and yet observations show them to possess important variations in the third dimension along the prominence axis with great arches with feet reaching down towards the solar surface. As an initial attempt to understand this structure we consider a three-dimensional linear force-free field model for the global magnetic field around a quiescent prominence. It consists of a fundamental together with a harmonic that is periodic along the prominence. At the solar surface there is a series of flux concentrations spaced out periodically on both sides of the prominence. Between a pair of oppositely directed flux concentration, the magnetic field in the prominence is stronger and tends to be less highly sheared than elsewhere. This modulation of the field strength and shear angle along the prominence decreases with height and almost disappears above 10 Mm. Prominence fields that increase with height occur when the shear is large and the length-scale for field variations perpendicular to the prominence exceeds that along it. The variation of the prominence height along the prominence is calculated and it is suggested that feet occur where the prominence sags down to low heights. For prominences of Normal polarity this tends to occur near supergranule centres where the transverse field is least, whereas for those of Inverse polarity it usually takes place near the chromospheric network where the transverse field is greatest. The effect of concentrating the base flux by including extra harmonics is also included. For Normal polarity prominences it tends to make the foot wider, and for Inverse polarity configurations, it usually creates deeper and narrower feet

  5. A comparison of mercury levels in feathers and eggs of osprey (Pandion haliaetus) in the North American Great Lakes.

    Science.gov (United States)

    Hughes, K D; Ewins, P J; Clark, K E

    1997-11-01

    Osprey (Pandion haliaetus) eggs and chick feathers were collected for mercury analysis from nests at four Great Lakes study areas in Ontario (three "naturally formed" lakes in southern Ontario and one reservoir in northern Ontario) and two New Jersey study areas in 1991-1994. Adult osprey feathers were sampled from three Great Lakes study areas in 1991. Feathers sampled from chicks (approximately 28-35 days old) appear to be better indicators of local contaminant conditions since spatial patterns of mercury in known prey, yellow perch (Perca flavescens), also collected in these areas, were more similar to chick feathers than to eggs. Mercury levels were less variable in chick feathers than in eggs. Estimates of biomagnification factors using prey of known size at these areas were also less variable in feathers than in eggs. At naturally formed lakes, no significant correlation in mercury levels between eggs and chick feathers from the same nest was apparent, suggesting that the source of mercury contamination was not the same in these two tissues: mercury levels in eggs reflect mercury acquired on the breeding grounds, wintering grounds, and migratory route; mercury levels in chick feathers reflect local dietary conditions on the breeding grounds. Mercury levels in both osprey eggs and chick feathers were higher at the Ogoki Reservoir than at naturally formed lakes. Adult osprey feathers had higher mercury concentrations than chick feathers. Mercury levels in osprey eggs, chick feathers, and adult feathers did not approach levels associated with toxic reproductive effects.

  6. Neutral Atom Diffusion in a Partially Ionized Prominence Plasma

    Science.gov (United States)

    Gilbert, Holly

    2010-01-01

    The support of solar prominences is normally described in terms of a magnetic force on the prominence plasma that balances the solar gravitational force. Because the prominence plasma is only partially ionized. it is necessary to consider in addition the support of the neutral component of the prominence plasma. This support is accomplished through a frictional interaction between the neutral and ionized components of the plasma, and its efficacy depends strongly on the degree of ionization of the plasma. More specifically, the frictional force is proportional to the relative flow of neutral and ion species, and for a sufficiently weakly ionized plasma, this flow must be relatively large to produce a frictional force that balances gravity. A large relative flow, of course, implies significant draining of neutral particles from the prominence. We evaluate the importance of this draining effect for a hydrogen-helium plasma, and consider the observational evidence for cross-field diffusion of neutral prominence material,

  7. Determination of the viability of chicken feather as oil spill clean-up ...

    African Journals Online (AJOL)

    In this study a comparative assessment was conducted between chicken feather and a conventional synthetic sorbent mat used in the oil industry to clean-up oil spill. The result of the study shows that chicken feather has higher oil sorption capacity and sorbed oil recoverability than the standard (synthetic sorbent mat), and ...

  8. Trade in Andean Condor Vulture gryphus feathers and body parts in ...

    African Journals Online (AJOL)

    body parts in the city of Cusco and the Sacred Valley,. Cusco region, Peru. Robert S. R. ... The sale of Andean Condor feathers and body parts is undertaken openly in the tourist markets of Cusco and the Sacred .... and shops. Prices in local currency – Nuevo Sol and US Dollar equivalent given in parentheses). Feather.

  9. The performance of broiler finisher birds fed varying levels of feather ...

    African Journals Online (AJOL)

    The performance of broiler finisher birds fed varying levels of feather meal as replacement for soya bean meal. ... meal increased, feed cost/ kg weight gain increased and both differed significantly (P<0.05) between treatment means, while the birds tolerated feather meal up to 7.5% inclusion level, 2.5% was the optimal.

  10. 76 FR 76115 - Revisions to the California State Implementation Plan, Feather River Air Quality Management District

    Science.gov (United States)

    2011-12-06

    ... the California State Implementation Plan, Feather River Air Quality Management District AGENCY... limited disapproval of revisions to the Feather River Air Quality Management District (FRAQMD) portion of..., Regulatory Planning and Review The Office of Management and Budget (OMB) has exempted this regulatory action...

  11. Comparison of four feed proteases for improvement of nutritive value of poultry feather meal

    DEFF Research Database (Denmark)

    Pedersen, Mads Brøgger; Yu, S; Plumstead, P

    2012-01-01

    in the production of cost-effective feather by-products for use as feed and fertilizers. The current study examined 4 commercial feed proteases from Bacillus subtilis, Bacillus licheniformis PWD-1, Aspergillus niger, and Serratia proteamaculans HY-3 used to hydrolyze chicken feather under different conditions...

  12. The preference for high-fiber feed in laying hens divergently selected on feather pecking.

    Science.gov (United States)

    Kalmendal, R; Bessei, W

    2012-08-01

    Earlier studies in laying hens have demonstrated a negative correlation between feather pecking and the dietary fiber content of the feed. However, the factors underlying this relationship are not fully understood. In the present experiment, we hypothesized that birds prone to feather pecking would prefer a diet supplemented with dietary fiber. Thus, the aim was to investigate the voluntary consumption of a wheat-soy control diet (CON) and a diet supplemented with 8% spelt hulls (FIB) on the expense of wheat in 20 individually caged hens selected for high feather pecking (HFP) behavior and 20 individually caged hens selected for low feather pecking (LFP) behavior. The proportional intake of FIB was 0.39 and significantly different from 0.50 (Phens (0.36; Phens had inferior plumage condition (Pfeed intake (Phens plucked more feathers from a simple inanimate feather-pecking model, but the number of feathers being pulled out did not correlate with the proportional intake of FIB. It was concluded that the preference for feed supplemented with spelt hulls was different between hens displaying different feather-pecking behavior. The underlying reason for such a difference needs further investigation.

  13. THE ENERGETIC COST OF FEATHER SYNTHESIS IS PROPORTIONAL TO BASAL METABOLIC-RATE

    NARCIS (Netherlands)

    VISSER, GH; DAAN, S

    1993-01-01

    The cost of feather production, C(f) (kJ . [g dry feathers]-1), differs substantially between species. We studied the molt cost in one insectivorous songbird (bluethroat, Luscinia s. svecica) and one granivorous songbird (common redpoll, Carduelis f. flammea), We wanted to test whether differences

  14. Heritability of feather pecking and open-field response of laying hens at two different ages

    NARCIS (Netherlands)

    Rodenburg, T.B.; Buitenhuis, A.J.; Ask, B.; Uitdehaag, K.A.; Koene, P.; Poel, van der J.J.; Bovenhuis, H.

    2003-01-01

    The objective of the current study was to estimate heritabilities. (h(2)) of feather pecking and open-field response of laying hens at two different ages. An F-2 cross, originating from a high and a low feather pecking line of laying hens, was used for the experiment. Each of the 630 birds of the

  15. Feathers at nests are potential female signals in the spotless starling.

    Science.gov (United States)

    Veiga, José P; Polo, Vicente

    2005-09-22

    Although the presence of feathers in the nest is widespread among birds, it has not been previously suggested that feathers can be used as sexual signals. Females of the spotless starling (Sturnus unicolor) regularly carry feathers to their nest, mostly during laying and incubation. We show that the arrangement of these feathers was non-random with respect to the side (obverse or reverse) placed upwards (which can be viewed from the nest entrance). Feathers of the wood pigeon (Columba palumbus) and the spotless starling, which exhibit higher ultraviolet and visible reflectance on their reverse side, were predominantly placed with this side upwards. On the contrary, feathers of the jay (Garrulus glandarius) were predominantly found exhibiting the obverse side, which possesses higher reflectance in this species. Feathers of the azure-winged magpie (Cyanopica cyana), with similar reflectance values on either side, were placed indiscriminately in obverse and reverse positions. The results suggest that feathers are arranged to maximize their conspicuousness within the nest and hence that they might be potentially used as intraspecific signals.

  16. Effect of an early bitter taste experience on subsequent feather-pecking behaviour in laying hens

    NARCIS (Netherlands)

    Harlander, A.; Beck, P.S.A.; Rodenburg, T.B.

    2010-01-01

    Recent studies showed that laying hens learn not to peck at bitter-tasting feathers from conspecifics. In the present experiment, feathers of newly hatched chicks were made distasteful by spraying them with a bitter-tasting substance (quinine). It was hypothesized that chicks could detect quinine

  17. Microorganisms associated with feathers of barn swallows in radioactively contaminated areas around chernobyl.

    Science.gov (United States)

    Czirják, Gábor Arpád; Møller, Anders Pape; Mousseau, Timothy A; Heeb, Philipp

    2010-08-01

    The Chernobyl catastrophe provides a rare opportunity to study the ecological and evolutionary consequences of low-level, environmental radiation on living organisms. Despite some recent studies about negative effects of environmental radiation on macroorganisms, there is little knowledge about the effect of radioactive contamination on diversity and abundance of microorganisms. We examined abundance patterns of total cultivable bacteria and fungi and the abundance of feather-degrading bacterial subset present on feathers of barn swallows (Hirundo rustica), a colonial migratory passerine, around Chernobyl in relation to levels of ground level environmental radiation. After controlling for confounding variables, total cultivable bacterial loads were negatively correlated with environmental radioactivity, whereas abundance of fungi and feather-degrading bacteria was not significantly related to contamination levels. Abundance of both total and feather-degrading bacteria increased with barn swallow colony size, showing a potential cost of sociality. Males had lower abundance of feather-degrading bacteria than females. Our results show the detrimental effects of low-level environmental radiation on total cultivable bacterial assemblage on feathers, while the abundance of other microorganism groups living on barn swallow feathers, such as feather-degrading bacteria, are shaped by other factors like host sociality or host sex. These data lead us to conclude that the ecological effects of Chernobyl may be more general than previously assumed and may have long-term implications for host-microbe interactions and overall ecosystem functioning.

  18. Feather bedding and childhood asthma associated with house dust mite sensitisation : a randomised controlled trial

    NARCIS (Netherlands)

    Glasgow, Nicholas J.; Ponsonby, Anne-Louise; Kemp, Andrew; Tovey, Euan; van Asperen, Peter; McKay, Karen; Forbes, Samantha

    Introduction Observational studies report inverse associations between the use of feather upper bedding (pillow and/or quilt) and asthma symptoms but there is no randomised controlled trial (RCT) evidence assessing the role of feather upper bedding as a secondary prevention measure. Objective To

  19. Plumas como enfeites da moda Feathers in fashion

    Directory of Open Access Journals (Sweden)

    Helmut Schindler

    2001-01-01

    Full Text Available O texto aborda a presença da plumária na moda feminina do século XIX. No Brasil, houve produção de enfeites com penas, que não provinha dos índios. Havia manufaturas que forneciam mercadorias para as lojas da capital. Com base nos relatos de viajantes que passaram pelo Brasil no século XIX, e no material depositado no Museu Estatal de Etnologia de Munique, o autor enfatiza as manufaturas existentes no Brasil e a captura indiscriminada de determinadas espécies de aves para atender a demanda da sociedade da época. Desde o século passado, as aves de penas mais bonitas passam a rarear, o que começa a ser acompanhado pela preocupação com o controle da caça.The article focus on the presence of plumage in the 19th century fashion. In Brazil, the feathers for the production of feather pieces were not necessarily supplied by Indians. There were manufacturers that supplied the stores in the country's capital with these pieces. Based on travelers' reports on nineteenth-century Brazil as well as on material from the State Museum of Ethnology in Munich, the author emphasizes the indiscriminate capture of some species of birds in order to face the demand of society at the time. In the 19th century, the most beautifully-feathered birds progressively began to become rare, which naturally brought forth the concern with uncontrolled bird capture.

  20. Birds of a feather: Neanderthal exploitation of raptors and corvids.

    Science.gov (United States)

    Finlayson, Clive; Brown, Kimberly; Blasco, Ruth; Rosell, Jordi; Negro, Juan José; Bortolotti, Gary R; Finlayson, Geraldine; Sánchez Marco, Antonio; Giles Pacheco, Francisco; Rodríguez Vidal, Joaquín; Carrión, José S; Fa, Darren A; Rodríguez Llanes, José M

    2012-01-01

    The hypothesis that Neanderthals exploited birds for the use of their feathers or claws as personal ornaments in symbolic behaviour is revolutionary as it assigns unprecedented cognitive abilities to these hominins. This inference, however, is based on modest faunal samples and thus may not represent a regular or systematic behaviour. Here we address this issue by looking for evidence of such behaviour across a large temporal and geographical framework. Our analyses try to answer four main questions: 1) does a Neanderthal to raptor-corvid connection exist at a large scale, thus avoiding associations that might be regarded as local in space or time?; 2) did Middle (associated with Neanderthals) and Upper Palaeolithic (associated with modern humans) sites contain a greater range of these species than Late Pleistocene paleontological sites?; 3) is there a taphonomic association between Neanderthals and corvids-raptors at Middle Palaeolithic sites on Gibraltar, specifically Gorham's, Vanguard and Ibex Caves? and; 4) was the extraction of wing feathers a local phenomenon exclusive to the Neanderthals at these sites or was it a geographically wider phenomenon?. We compiled a database of 1699 Pleistocene Palearctic sites based on fossil bird sites. We also compiled a taphonomical database from the Middle Palaeolithic assemblages of Gibraltar. We establish a clear, previously unknown and widespread, association between Neanderthals, raptors and corvids. We show that the association involved the direct intervention of Neanderthals on the bones of these birds, which we interpret as evidence of extraction of large flight feathers. The large number of bones, the variety of species processed and the different temporal periods when the behaviour is observed, indicate that this was a systematic, geographically and temporally broad, activity that the Neanderthals undertook. Our results, providing clear evidence that Neanderthal cognitive capacities were comparable to those of

  1. Keratin based bioplastic film from chicken feathers and its characterization.

    Science.gov (United States)

    Ramakrishnan, Navina; Sharma, Swati; Gupta, Arun; Alashwal, Basma Yahya

    2018-05-01

    Plastics have been one of the highly valued materials and it plays an significant role in human's life such as in food packaging and biomedical applications. Bioplastic materials can gradually work as a substitute for various materials based on fossil oil. The issue like sustainability and environmental challenges which occur due to manufacturing and disposal of synthetic plastics can be conquering by bio-based plastics. Feathers are among the most inexpensive abundant, and renewable protein sources. Feathers disposal to the landfills leads to environmental pollutions and it results into wastage of 90% of protein raw material. Keratin is non-burning hydrophilic, and biodegradable due to which it can be applicable in various ways via chemical processing. Main objective of this research is to synthesis bioplastic using keratin from chicken feathers. Extracted keratin solution mixed with different concentration of glycerol (2 to 10%) to produce plastic films. The mixture was stirred under constant magnetic stirring at 60 °C for 5 h. The mixtures are then poured into aluminum weighing boat and dried in an oven at 60 °C for 24 h. The mechanical properties of the samples were tested and the physic-chemical properties of the bioplastic were studied. According to the results, Scanning Electron Microscopy test showed good compatible morphologies without holes, cavity and edge. The difference in chemical composition was analyzed using Fourier transform infrared spectroscopy (FTIR). The samples were also characterized by thermo gravimetric analysis (TGA), differential scanning calorimetry (DSC), X-Ray diffraction (XRD) to check the thermal and crystallinity properties. Other than that, bioplastic made up from keratin with 2% of glycerol has the best mechanical and thermal properties. According to biodegradability test, all bioplastic produced are proven biodegradable. Therefore, the results showed possible application of the film as an alternative to fossil oil

  2. Trace element contamination in feather and tissue samples from Anna’s hummingbirds

    Science.gov (United States)

    Mikoni, Nicole A.; Poppenga, Robert H.; Ackerman, Joshua T.; Foley, Janet E.; Hazlehurst, Jenny; Purdin, Güthrum; Aston, Linda; Hargrave, Sabine; Jelks, Karen; Tell, Lisa A.

    2017-01-01

    Trace element contamination (17 elements; Be, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Mo, Cd, Ba, Hg, Tl, and Pb) of live (feather samples only) and deceased (feather and tissue samples) Anna's hummingbirds (Calypte anna) was evaluated. Samples were analyzed using inductively coupled plasma-mass spectrometry (ICP-MS; 17 elements) and atomic absorption spectrophotometry (Hg only). Mean plus one standard deviation (SD) was considered the benchmark, and concentrations above the mean + 1 SD were considered elevated above normal. Contour feathers were sampled from live birds of varying age, sex, and California locations. In order to reduce thermal impacts, minimal feathers were taken from live birds, therefore a novel method was developed for preparation of low mass feather samples for ICP-MS analysis. The study found that the novel feather preparation method enabled small mass feather samples to be analyzed for trace elements using ICP-MS. For feather samples from live birds, all trace elements, with the exception of beryllium, had concentrations above the mean + 1 SD. Important risk factors for elevated trace element concentrations in feathers of live birds were age for iron, zinc, and arsenic, and location for iron, manganese, zinc, and selenium. For samples from deceased birds, ICP-MS results from body and tail feathers were correlated for Fe, Zn, and Pb, and feather concentrations were correlated with renal (Fe, Zn, Pb) or hepatic (Hg) tissue concentrations. Results for AA spectrophotometry analyzed samples from deceased birds further supported the ICP-MS findings where a strong correlation between mercury concentrations in feather and tissue (pectoral muscle) samples was found. These study results support that sampling feathers from live free-ranging hummingbirds might be a useful, non-lethal sampling method for evaluating trace element exposure and provides a sampling alternative since their small body size limits traditional sampling of blood and tissues. The

  3. Aerodynamics and Ecomorphology of Flexible Feathers and Morphing Bird Wings

    Science.gov (United States)

    Klaassen van Oorschot, Brett

    Birds are talented fliers capable of vertical take-off and landing, navigating turbulent air, and flying thousands of miles without rest. How is this possible? What allows birds to exploit the aerial environment with such ease? In part, it may be because bird wings are unlike any engineered wing. They are flexible, strong, lightweight, and dynamically capable of changes in shape on a nearly instantaneous basis (Rayner, 1988; Tobalske, 2007). Moreover, much of this change is passive, modulated only by changes in airflow angle and velocity. Birds actively morph their wings and their feathers morph passively in response to airflow to meet aerodynamic demands. Wings are highly adapted to myriad aeroecological factors and aerodynamic conditions (e.g. Lockwood et al., 1998; Bowlin and Winkler, 2004). This dissertation contains the results of my research on the complexities of morphing avian wings and feathers. I chose to study three related-but-discrete aspects of the avian wing: 1) the aerodynamics of morphing wings during take-off and gliding flight, 2) the presence and significance of wing tip slots across the avian clade, and 3) the aerodynamic role of the emarginate primary feathers that form these wing tip slots. These experiments ask fundamental questions that have intrigued me since childhood: Why do birds have different wing shapes? And why do some birds have slotted wing tips? It's fair to say that you will not find definitive answers here--rather, you will find the methodical, incremental addition of new hypotheses and empirical evidence which will serve future researchers in their own pursuits of these questions. The first chapter explores active wing morphing in two disparate aerodynamic regimes: low-advance ratio flapping (such as during takeoff) and high-advance ratio gliding. This chapter was published in the Journal of Experimental Biology (Klaassen van Oorschot et al., 2016) with the help of an undergraduate researcher, Emily Mistick. We found that wing

  4. Hydrophobic duck feathers and their simulation on textile substrates for water repellent treatment

    International Nuclear Information System (INIS)

    Liu Yuyang; Chen Xianqiong; Xin, J H

    2008-01-01

    Inspired by the non-wetting phenomena of duck feathers, the water repellent property of duck feathers was studied at the nanoscale. The microstructures of the duck feather were investigated by a scanning electron microscope (SEM) imaging method through a step-by-step magnifying procedure. The SEM results show that duck feathers have a multi-scale structure and that this multi-scale structure as well as the preening oil are responsible for their super hydrophobic behavior. The microstructures of the duck feather were simulated on textile substrates using the biopolymer chitosan as building blocks through a novel surface solution precipitation (SSP) method, and then the textile substrates were further modified with a silicone compound to achieve low surface energy. The resultant textiles exhibit super water repellent properties, thus providing a simple bionic way to create super hydrophobic surfaces on soft substrates using flexible material as building blocks

  5. Mechanical and Morphology Properties of Feather Fiber Composite for Dental Post Application

    International Nuclear Information System (INIS)

    Siti Maizatul Farhain Salehuddin; Mohammed Rafiq Abdul Kadir; Eshamsul Sulaiman; Noor Hayaty Abu Kasim

    2014-01-01

    Feather/plastic composite material was fabricated from polymethyl methacrylate (PMMA), feather fiber (FF) and montmorillonite (MMT) using brabender internal mixer. PMMA based composites were produced with 1, 3, 5, 7 and 10 phr composite of mass feather fiber with and without 4 % of montmorillonite (MMT). Alkali treatment was used to improve the interfacial adhesion among the feather fiber (FF) and the PMMA. Flexural properties of FF/ PMMA and FF/ PMMA/ MMT composites were investigated. Composites were analyzed by Scanning Electron (SEM) and Fourier Transform Infra Red (FTIR) spectroscopy techniques. The result showed that, the addition of FF significantly increased the flexural strength of the composites. The hydrophobic nature of feather fiber displayed an excellent compatibility among fibers and PMMA matrix. (author)

  6. Spectral tuning of Amazon parrot feather coloration by psittacofulvin pigments and spongy structures.

    Science.gov (United States)

    Tinbergen, Jan; Wilts, Bodo D; Stavenga, Doekele G

    2013-12-01

    The feathers of Amazon parrots are brightly coloured. They contain a unique class of pigments, the psittacofulvins, deposited in both barbs and barbules, causing yellow or red coloured feathers. In specific feather areas, spongy nanostructured barb cells exist, reflecting either in the blue or blue-green wavelength range. The blue-green spongy structures are partly enveloped by a blue-absorbing, yellow-colouring pigment acting as a spectral filter, thus yielding a green coloured barb. Applying reflection and transmission spectroscopy, we characterized the Amazons' pigments and spongy structures, and investigated how they contribute to the feather coloration. The reflectance spectra of Amazon feathers are presumably tuned to the sensitivity spectra of the visual photoreceptors.

  7. Pronounced variation in tarsal and foot feathering in the upland buzzard (Buteo hemilasius) in Mongolia

    Science.gov (United States)

    Ellis, D.H.; Woffinden, N.; Whitlock, P.L.; Tsengeg, Pu

    1999-01-01

    During 1994, 1995, 1997, and 1998 expeditions across Mongolia, we located over 250 upland buzzard (Buteo hemilasius) nests. At these, we noted considerable morphological variation in plumage coloration and in leg pterylosis. In 1997 and 1998, we examined 131 nests scattered across eastern and central Mongolia and report here the tarsal condition of 119 nestlings from 59 broods where young were at least 2 weeks of age. Of 119 birds carefully examined, 50 (42%) had less than fully feathered tarsi and 4 of the 69 with fully feathered tarsi had scattered feathers on their toes. Thus, 54 of 119 birds (45%) in some way deviated from the feathered tarsibare toes condition. This extraordinary degree of variability in feather patterns may be best explained as the result of extensive and relatively recent hybridization between the longlegged (Buteo rufinus) and roughlegged (B. lagopus) buzzards and/or between long-legged and upland buzzards.

  8. Hide depilation and feather disintegration studies with keratinolytic serine protease from a novel Bacillus subtilis isolate.

    Science.gov (United States)

    Pillai, Priya; Archana, G

    2008-03-01

    Keratinases play an important role in biotechnological applications such as improvement of feather meal, enzymatic dehairing and production of amino acids or peptides from high molecular weight substrates. Bacillus subtilis P13, isolated from Vajreshwari hot spring (45-50 degrees C) near Mumbai, India, produces a neutral serine protease and has an optimum temperature of 65 degrees C. This enzyme preparation was keratinolytic in nature and could disintegrate whole chicken feathers, except for the remnants of shafts. The enzyme preparation also exhibited depilation of goat hides with the recovery of intact animal hair. The enzyme preparation could release peptides from ground feathers and bring about their weight reduction; however, similar action on hair was relatively weak. A single major PMSF-sensitive protease band could be detected upon zymogram analysis, indicating that a single enzyme may be responsible for feather degradation and hide depilation. The importance of these findings in the biotechnological application for feather and leather industries is discussed.

  9. Interpopulation Variation in Contour Feather Structure Is Environmentally Determined in Great Tits

    Science.gov (United States)

    Broggi, Juli; Gamero, Anna; Hohtola, Esa; Orell, Markku; Nilsson, Jan-Åke

    2011-01-01

    Background The plumage of birds is important for flying, insulation and social communication. Contour feathers cover most of the avian body and among other functions they provide a critical insulation layer against heat loss. Feather structure and composition are known to vary among individuals, which in turn determines variation in the insulation properties of the feather. However, the extent and the proximate mechanisms underlying this variation remain unexplored. Methodology/Principal Findings We analyzed contour feather structure from two different great tit populations adapted to different winter regimes, one northern population in Oulu (Finland) and one southern population in Lund (Sweden). Great tits from the two populations differed significantly in feather structure. Birds from the northern population had a denser plumage but consisting of shorter feathers with a smaller proportion containing plumulaceous barbs, compared with conspecifics from the southern population. However, differences disappeared when birds originating from the two populations were raised and moulted in identical conditions in a common-garden experiment located in Oulu, under ad libitum nutritional conditions. All birds raised in the aviaries, including adult foster parents moulting in the same captive conditions, developed a similar feather structure. These feathers were different from that of wild birds in Oulu but similar to wild birds in Lund, the latter moulting in more benign conditions than those of Oulu. Conclusions/Significance Wild populations exposed to different conditions develop contour feather differences either due to plastic responses or constraints. Environmental conditions, such as nutrient availability during feather growth play a crucial role in determining such differences in plumage structure among populations. PMID:21949798

  10. Does feather corticosterone reflect individual quality or external stress in arctic-nesting migratory birds?

    Directory of Open Access Journals (Sweden)

    Pierre Legagneux

    Full Text Available The effects of environmental perturbations or stressors on individual states can be carried over to subsequent life stages and ultimately affect survival and reproduction. The concentration of corticosterone (CORT in feathers is an integrated measure of hypothalamic-pituitary-adrenal activity during the molting period, providing information on the total baseline and stress-induced CORT secreted during the period of feather growth. Common eiders and greater snow geese replace all flight feathers once a year during the pre-basic molt, which occurs following breeding. Thus, CORT contained in feathers of pre-breeding individuals sampled in spring reflects the total CORT secreted during the previous molting event, which may provide insight into the magnitude or extent of stress experienced during this time period. We used data from multiple recaptures to disentangle the contribution of individual quality vs. external factors (i.e., breeding investment or environmental conditions on feather CORT in arctic-nesting waterfowl. Our results revealed no repeatability of feather CORT within individuals of either species. In common eiders, feather CORT was not affected by prior reproductive investment, nor by pre-breeding (spring body condition prior to the molting period. Individual feather CORT greatly varied according to the year, and August-September temperatures explained most of the annual variation in feather CORT. Understanding mechanisms that affect energetic costs and stress responses during molting will require further studies either using long-term data or experiments. Although our study period encompassed only five years, it nonetheless provides evidence that CORT measured in feathers likely reflects responses to environmental conditions experienced by birds during molt, and could be used as a metric to study carry-over effects.

  11. Biomechanics of the Peacock’s Display: How Feather Structure and Resonance Influence Multimodal Signaling

    Science.gov (United States)

    Dakin, Roslyn; McCrossan, Owen; Hare, James F.; Montgomerie, Robert; Amador Kane, Suzanne

    2016-01-01

    Courtship displays may serve as signals of the quality of motor performance, but little is known about the underlying biomechanics that determines both their signal content and costs. Peacocks (Pavo cristatus) perform a complex, multimodal “train-rattling” display in which they court females by vibrating the iridescent feathers in their elaborate train ornament. Here we study how feather biomechanics influences the performance of this display using a combination of field recordings and laboratory experiments. Using high-speed video, we find that train-rattling peacocks stridulate their tail feathers against the train at 25.6 Hz, on average, generating a broadband, pulsating mechanical sound at that frequency. Laboratory measurements demonstrate that arrays of peacock tail and train feathers have a broad resonant peak in their vibrational spectra at the range of frequencies used for train-rattling during the display, and the motion of feathers is just as expected for feathers shaking near resonance. This indicates that peacocks are able to drive feather vibrations energetically efficiently over a relatively broad range of frequencies, enabling them to modulate the feather vibration frequency of their displays. Using our field data, we show that peacocks with longer trains use slightly higher vibration frequencies on average, even though longer train feathers are heavier and have lower resonant frequencies. Based on these results, we propose hypotheses for future studies of the function and energetics of this display that ask why its dynamic elements might attract and maintain female attention. Finally, we demonstrate how the mechanical structure of the train feathers affects the peacock’s visual display by allowing the colorful iridescent eyespots–which strongly influence female mate choice–to remain nearly stationary against a dynamic iridescent background. PMID:27119380

  12. A lifting line model to investigate the influence of tip feathers on wing performance

    International Nuclear Information System (INIS)

    Fluck, M; Crawford, C

    2014-01-01

    Bird wings have been studied as prototypes for wing design since the beginning of aviation. Although wing tip slots, i.e. wings with distinct gaps between the tip feathers (primaries), are very common in many birds, only a few studies have been conducted on the benefits of tip feathers on the wing's performance, and the aerodynamics behind tip feathers remains to be understood. Consequently most aircraft do not yet copy this feature. To close this knowledge gap an extended lifting line model was created to calculate the lift distribution and drag of wings with tip feathers. With this model, is was easily possible to combine several lifting surfaces into various different birdwing-like configurations. By including viscous drag effects, good agreement with an experimental tip slotted reference case was achieved. Implemented in C++ this model resulted in computation times of less than one minute per wing configuration on a standard notebook computer. Thus it was possible to analyse the performance of over 100 different wing configurations with and without tip feathers. While generally an increase in wing efficiency was obtained by splitting a wing tip into distinct, feather-like winglets, the best performance was generally found when spreading more feathers over a larger dihedral angle out of the wing plane. However, as the results were very sensitive to the precise geometry of the feather fan (especially feather twist) a careless set-up could just as easily degrade performance. Hence a detailed optimization is recommended to realize the full benefits by simultaneously optimizing feather sweep, twist and dihedral angles. (paper)

  13. Evaluating cleansing effects on trace elements and stable isotope values in feathers of oiled birds.

    Science.gov (United States)

    Valladares, Sonia; Moreno, Roćio; Jover, Lluis; Sanpera, Carola

    2010-01-01

    Feathers of seabirds are widely used as a nondestructive tissue for pollution monitoring of trace elements, as well as convenient samples for trophic ecology studies by means of stable isotope analysis (SIA). Nevertheless, feathers can be occasionally impregnated with oil from deliberate ship discharges and from massive oil spill accidents. The feather structure makes them effective traps for particles and are subject to external contamination. It is unknown to what extent the oil adhered to feathers can change trace element concentrations or stable isotope signatures. This study has two primary objectives: (1) to assess if there are differences between trace element concentrations and stable isotope signatures of oiled and clean feathers, and (2) to determine if the cleansing of oiled feathers using commonly applied techniques such as sodium hydroxide (NaOH) washes in combination with an organic solvent (hexane) is more effective than using NaOH alone. In order to do this, we analysed trace elements (Se, Hg, Pb, Cu and Zn) and stable isotopes (delta(13)C and delta(15)N) of individual feathers of yellow-legged gulls (Larus michahellis) which were affected by the 2002 Prestige oil spill in Galicia (NW Spain). Two sets of feathers were analysed, one group were oil-free (Control group) and the other had oil adhered to its surface (Oiled group). We expected to find differences between control and oiled feathers when cleaning exclusively with NaOH and no differences when using hexane. Our results did not show significant differences between Control and Oiled groups as a consequence of the cleansing method used. Unexpectedly, the additional cleansing with hexane resulted in decreasing selenium concentrations and increasing zinc and delta(15)N values in all groups of feathers.

  14. Does feather corticosterone reflect individual quality or external stress in arctic-nesting migratory birds?

    Science.gov (United States)

    Legagneux, Pierre; Harms, N Jane; Gauthier, Gilles; Chastel, Olivier; Gilchrist, H Grant; Bortolotti, Gary; Bêty, Joël; Soos, Catherine

    2013-01-01

    The effects of environmental perturbations or stressors on individual states can be carried over to subsequent life stages and ultimately affect survival and reproduction. The concentration of corticosterone (CORT) in feathers is an integrated measure of hypothalamic-pituitary-adrenal activity during the molting period, providing information on the total baseline and stress-induced CORT secreted during the period of feather growth. Common eiders and greater snow geese replace all flight feathers once a year during the pre-basic molt, which occurs following breeding. Thus, CORT contained in feathers of pre-breeding individuals sampled in spring reflects the total CORT secreted during the previous molting event, which may provide insight into the magnitude or extent of stress experienced during this time period. We used data from multiple recaptures to disentangle the contribution of individual quality vs. external factors (i.e., breeding investment or environmental conditions) on feather CORT in arctic-nesting waterfowl. Our results revealed no repeatability of feather CORT within individuals of either species. In common eiders, feather CORT was not affected by prior reproductive investment, nor by pre-breeding (spring) body condition prior to the molting period. Individual feather CORT greatly varied according to the year, and August-September temperatures explained most of the annual variation in feather CORT. Understanding mechanisms that affect energetic costs and stress responses during molting will require further studies either using long-term data or experiments. Although our study period encompassed only five years, it nonetheless provides evidence that CORT measured in feathers likely reflects responses to environmental conditions experienced by birds during molt, and could be used as a metric to study carry-over effects.

  15. A trade-off between reproduction and feather growth in the barn swallow (Hirundo rustica.

    Directory of Open Access Journals (Sweden)

    Nicola Saino

    Full Text Available Physiological trade-offs mediated by limiting energy, resources or time constrain the simultaneous expression of major functions and can lead to the evolution of temporal separation between demanding activities. In birds, plumage renewal is a demanding activity, which accomplishes fundamental functions, such as allowing thermal insulation, aerodynamics and socio-sexual signaling. Feather renewal is a very expensive and disabling process, and molt is often partitioned from breeding and migration. However, trade-offs between feather renewal and breeding have been only sparsely studied. In barn swallows (Hirundo rustica breeding in Italy and undergoing molt during wintering in sub-Saharan Africa, we studied this trade-off by removing a tail feather from a large sample of individuals and analyzing growth bar width, reflecting feather growth rate, and length of the growing replacement feather in relation to the stage in the breeding cycle at removal and clutch size. Growth bar width of females and length of the growing replacement feather of both sexes were smaller when the original feather had been removed after clutch initiation. Importantly, in females both growth bar width and replacement feather length were negatively predicted by clutch size, and more strongly so for large clutches and when feather removal occurred immediately after clutch completion. Hence, we found strong, coherent evidence for a trade-off between reproduction, and laying effort in particular, and the ability to generate new feathers. These results support the hypothesis that the derived condition of molting during wintering in long-distance migrants is maintained by the costs of overlapping breeding and molt.

  16. Interpopulation variation in contour feather structure is environmentally determined in great tits.

    Directory of Open Access Journals (Sweden)

    Juli Broggi

    Full Text Available The plumage of birds is important for flying, insulation and social communication. Contour feathers cover most of the avian body and among other functions they provide a critical insulation layer against heat loss. Feather structure and composition are known to vary among individuals, which in turn determines variation in the insulation properties of the feather. However, the extent and the proximate mechanisms underlying this variation remain unexplored.We analyzed contour feather structure from two different great tit populations adapted to different winter regimes, one northern population in Oulu (Finland and one southern population in Lund (Sweden. Great tits from the two populations differed significantly in feather structure. Birds from the northern population had a denser plumage but consisting of shorter feathers with a smaller proportion containing plumulaceous barbs, compared with conspecifics from the southern population. However, differences disappeared when birds originating from the two populations were raised and moulted in identical conditions in a common-garden experiment located in Oulu, under ad libitum nutritional conditions. All birds raised in the aviaries, including adult foster parents moulting in the same captive conditions, developed a similar feather structure. These feathers were different from that of wild birds in Oulu but similar to wild birds in Lund, the latter moulting in more benign conditions than those of Oulu.Wild populations exposed to different conditions develop contour feather differences either due to plastic responses or constraints. Environmental conditions, such as nutrient availability during feather growth play a crucial role in determining such differences in plumage structure among populations.

  17. QUIESCENT PROMINENCES IN THE ERA OF ALMA: SIMULATED OBSERVATIONS USING THE 3D WHOLE-PROMINENCE FINE STRUCTURE MODEL

    Energy Technology Data Exchange (ETDEWEB)

    Gunár, Stanislav; Heinzel, Petr [Astronomical Institute, The Czech Academy of Sciences, 25165 Ondřejov (Czech Republic); Mackay, Duncan H. [School of Mathematics and Statistics, University of St Andrews, North Haugh, St Andrews KY16 9SS (United Kingdom); Anzer, Ulrich [Max-Planck-Institut für Astrophysik, Karl-Schwarzschild-Str. 1, D-85740 Garching bei München (Germany)

    2016-12-20

    We use the detailed 3D whole-prominence fine structure model to produce the first simulated high-resolution ALMA observations of a modeled quiescent solar prominence. The maps of synthetic brightness temperature and optical thickness shown in the present paper are produced using a visualization method for synthesis of the submillimeter/millimeter radio continua. We have obtained the simulated observations of both the prominence at the limb and the filament on the disk at wavelengths covering a broad range that encompasses the full potential of ALMA. We demonstrate here extent to which the small-scale and large-scale prominence and filament structures will be visible in the ALMA observations spanning both the optically thin and thick regimes. We analyze the relationship between the brightness and kinetic temperature of the prominence plasma. We also illustrate the opportunities ALMA will provide for studying the thermal structure of the prominence plasma from the cores of the cool prominence fine structure to the prominence–corona transition region. In addition, we show that detailed 3D modeling of entire prominences with their numerous fine structures will be important for the correct interpretation of future ALMA observations of prominences.

  18. Study of a Large Helical Eruptive Prominence Associated with ...

    Indian Academy of Sciences (India)

    2001-04-21

    Apr 21, 2001 ... morphology of the event, energy budget of the prominence and associated. CMEs. ... magnetically driven and internally powered. Key words. ... Solar prominences are ribbons of cool (∼8000 K) dense gas (∼10. −11 gcm. −3. ) ...

  19. Feather-picking psittacines: histopathology and species trends.

    Science.gov (United States)

    Garner, M M; Clubb, S L; Mitchell, M A; Brown, L

    2008-05-01

    Histologic findings are described for 408 feather-picking or self-mutilating psittacines with the use of biopsies from clinically affected and unaffected skin. Inflammatory skin disease was diagnosed in 210 birds, and traumatic skin disease was diagnosed in 198 birds. Criteria used for the diagnosis of inflammatory skin disease included the presence of perivascular inflammation in the superficial or deep dermis of clinically affected and unaffected sites. The primary histologic criteria for the diagnosis of traumatic skin disease were superficial dermal scarring with or without inflammation in the affected sites and an absence of inflammation in the unaffected sites. The inflammatory cells associated with the lesions were typically lymphocytes and occasionally plasma cells, histiocytes, and granulocytes. A preponderance of inflammatory skin disease was seen in macaws (Ara spp.) and Amazon parrots (Amazona spp.). A preponderance of traumatic skin disease was seen in cockatoos (Cacatua spp.) and African grey parrots (Psittacus erithacus). The prevalence of each was approximately equal in several other species, including conures (Aratinga and Pyrrhura spp.), eclectus parrots (Eclectus roratus), quaker parrots (Myiopsitta monachus), cockatiels (Nymphicus hollandicus), parakeets (Cyanorhamphus and Psittacula spp.), and caiques (Pionites spp.). No geographic or gender-based trends were identified. These findings could be helpful for identifying and treating birds with feather-picking disorders.

  20. Energy value of meat in selected species of feathered game

    Directory of Open Access Journals (Sweden)

    František Vitula

    2011-01-01

    Full Text Available The aim of this work was to compare gross energy (GE in breast and thigh muscles in the following six species of feathered game reared in Europe: guineafowl (Numida meleagris, common pheasant (Phasianus colchicus, Japanese quail (Coturnix coturnix japonica, chukar (Alectoris chucar, grey partridge (Perdix perdix and wild turkey (Meleagris gallopavo. Calorimetric analysis revealed significant (P ≤ 0.05 and highly significant (P ≤ 0.01 differences between individual species in the content of energy in breast and thigh muscles. The highest content of energy (recalculated to dry matter was found in breast muscles from wild turkey (24.75 MJ·kg-1 and Japanese quail (24.57 MJ·kg-1 whereas the highest content of energy (recalculated to dry matter in thigh muscles was found in Japanese quail and grey partridge. Highly significant (P ≤ 0.01 differences in the energy content were also found between breast and thigh muscles in all studied game species except for wild turkey. Differences in the content of energy in muscles between individual species occur mainly due to different contents of fat in muscles. This is also confirmed by high correlation coefficients between the content of energy and the content of fat in breast (r = 0.912 and thigh muscles (r = 0.878. Our study provides more specific data on the amount of energy in muscles of major species of feathered game reared in Europe and significantly extends current knowledge in this field.

  1. MAGNETIC FIELD IN ATYPICAL PROMINENCE STRUCTURES: BUBBLE, TORNADO, AND ERUPTION

    Energy Technology Data Exchange (ETDEWEB)

    Levens, P. J.; Labrosse, N. [SUPA School of Physics and Astronomy, University of Glasgow, Glasgow G12 8QQ (United Kingdom); Schmieder, B. [LESIA, Observatoire de Paris, PSL Research University, CNRS, Sorbonne Universités, UPMC Univ. Paris 06, Univ. Paris Diderot, Sorbonne Paris Cité, 5 place Jules Janssen, F-92195 Meudon (France); López Ariste, A. [IRAP—CNRS UMR 5277, 14, Av. E. Belin, F-31400 Toulouse (France); Dalmasse, K. [CISL/HAO, National Center for Atmospheric Research, P.O. Box 3000, Boulder, CO 80307-3000 (United States); Gelly, B., E-mail: p.levens.1@research.gla.ac.uk, E-mail: brigitte.schmieder@obspm.fr [CNRS UMR 3718 THEMIS, La Laguna, Tenerife (Spain)

    2016-08-01

    Spectropolarimetric observations of prominences have been obtained with the THEMIS telescope during four years of coordinated campaigns. Our aim is now to understand the conditions of the cool plasma and magnetism in “atypical” prominences, namely when the measured inclination of the magnetic field departs, to some extent, from the predominantly horizontal field found in “typical” prominences. What is the role of the magnetic field in these prominence types? Are plasma dynamics more important in these cases than the magnetic support? We focus our study on three types of “atypical” prominences (tornadoes, bubbles, and jet-like prominence eruptions) that have all been observed by THEMIS in the He i D{sub 3} line, from which the Stokes parameters can be derived. The magnetic field strength, inclination, and azimuth in each pixel are obtained by using the inversion method of principal component analysis on a model of single scattering in the presence of the Hanle effect. The magnetic field in tornadoes is found to be more or less horizontal, whereas for the eruptive prominence it is mostly vertical. We estimate a tendency toward higher values of magnetic field strength inside the bubbles than outside in the surrounding prominence. In all of the models in our database, only one magnetic field orientation is considered for each pixel. While sufficient for most of the main prominence body, this assumption appears to be oversimplified in atypical prominence structures. We should consider these observations as the result of superposition of multiple magnetic fields, possibly even with a turbulent field component.

  2. Variation of heavy metals within and among feathers of birds of prey: effects of molt and external contamination

    Energy Technology Data Exchange (ETDEWEB)

    Dauwe, T.; Bervoets, L.; Pinxten, R.; Blust, R.; Eens, M

    2003-08-01

    Concentrations of many heavy metals in feathers, except Hg, did not reflect the molting sequence, suggesting external contamination. - In this study we examined the effect of external contamination on the heavy metal (Ag, Al, As, Cd, Co, Cr, Cu, Fe, Hg, Mn, Ni, Pb and Zn) concentration in feathers. We compared the heavy metal content among the 10 primary wing feathers of sparrowhawks (Accipiter nisus), little owls (Athene nocta) and barn owls (Tyto alba) and the variation within the outermost tail feather of sparrowhawks and tawny owls (Strix aluco). The concentration of Hg was significantly higher in feathers molted first, suggesting that levels in feathers reflect levels in the blood during formation. For some other elements (Al, Co, Ni, Pb, Zn) on the other hand, there are strong indications that external contamination may have an important impact on the levels detected in the feathers. This should be taken into account in future monitoring studies.

  3. Reassessment of the wing feathers of Archaeopteryx lithographica suggests no robust evidence for the presence of elongated dorsal wing coverts.

    Directory of Open Access Journals (Sweden)

    Robert L Nudds

    Full Text Available Recently it was proposed that the primary feathers of Archaeopteryx lithographica (HMN1880 were overlaid by long covert feathers, and that a multilayered feathered wing was a feature of early fossils with feathered forelimbs. The proposed long covert feathers of Archaeopteryx were previously interpreted as dorsally displaced remiges or a second set of impressions made by the wing. The following study shows that the qualitative arguments forwarded in support of the elongated covert hypothesis are neither robust nor supported quantitatively. The idea that the extant bird wing with its single layer of overlapping primaries evolved from an earlier multilayered heavily coveted feathered forelimb as seen in Anchiornis huxleyi is reasonable. At this juncture, however, it is premature to conclude unequivocally that the wing of Archaeopteryx consisted of primary feathers overlaid with elongated coverts.

  4. Keratin Production by Decomposing Feather Waste Using Some Local Bacillus spp. Isolated from Poultry Soil

    Directory of Open Access Journals (Sweden)

    Mojtaba Salouti

    2016-12-01

    Full Text Available Background: Feather waste is generated in large amounts as a by-product of commercial poultry processing. The main component of feather is keratin. The main purpose of this study was to identify Bacillus spp. (the keratinolytic bacteria that are able to degrade the feather for producing keratin. Methods: Bacillus spp. Were isolated from the waste of poultries located in Miyaneh city. The bacteria were grown on basal medium containing 1% hen feather as the sole source of carbon ,nitrogen, sulfur and energy at 27ºC for 7 days. Then,the isolates capable of feather degrading were identified. The Bradford method was used to assay the production of keratin in the feather samples. Different pH and temperatures were studied to determine the best conditions for production of keratinase enzyme. Results: Seven Bacillus spp. including: B. pumilis, B. subtilis, B. firmus, B. macerance, B. popilliae, B. lentimorbus and B. larvae were found to be able to degrade the feather with different abilities. Conclusion: B. subtilis was found to be most productive isolate for keratinase enzyme production.

  5. 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

  6. Anaerobic digestion of chicken feather with swine manure or slaughterhouse sludge for biogas production.

    Science.gov (United States)

    Xia, Yun; Massé, Daniel I; McAllister, Tim A; Beaulieu, Carole; Ungerfeld, Emilio

    2012-03-01

    Biogas production from anaerobic digestion of chicken feathers with swine manure or slaughterhouse sludge was assessed in two separate experiments. Ground feathers without any pre-treatment were added to 42-L digesters inoculated with swine manure or slaughterhouse sludge, representing 37% and 23% of total solids, respectively and incubated at 25°C in batch mode. Compared to the control without feather addition, total CH(4) production increased by 130% (Pswine manure and the slaughterhouse sludge digesters, respectively. Mixed liquor NH(4)N concentration increased (Pdigestion to 6.9 and 3.5 g/L at the end of digestion in the swine manure and the slaughterhouse sludge digesters, respectively. The fraction of proteolytic microorganisms increased (Pdigestion from 12.5% to 14.5% and 11.3% to 13.0% in the swine manure and the slaughterhouse sludge digesters with feather addition, respectively, but decreased in the controls. These results are reflective of feather digestion. Feather addition did not affect CH(4) yields of the swine manure digesters (P=0.082) and the slaughterhouse sludge digesters (P=0.21), indicating that feathers can be digested together with swine manure or slaughterhouse sludge without negatively affecting the digestion of swine manure and slaughterhouse sludge. Crown Copyright © 2011. Published by Elsevier Ltd. All rights reserved.

  7. Viscoelastic Characterization of Long-Eared Owl Flight Feather Shaft and the Damping Ability Analysis

    Directory of Open Access Journals (Sweden)

    Jia-li Gao

    2014-01-01

    Full Text Available Flight feather shaft of long-eared owl is characterized by a three-parameter model for linear viscoelastic solids to reveal its damping ability. Uniaxial tensile tests of the long-eared owl, pigeon, and golden eagle flight feather shaft specimens were carried out based on Instron 3345 single column material testing system, respectively, and viscoelastic response of their stress and strain was described by the standard linear solid model. Parameter fitting result obtained from the tensile tests shows that there is no significant difference in instantaneous elastic modulus for the three birds’ feather shafts, but the owl shaft has the highest viscosity, implying more obvious viscoelastic performance. Dynamic mechanical property was characterized based on the tensile testing results. Loss factor (tanδ of the owl flight feather shaft was calculated to be 1.609 ± 0.238, far greater than those of the pigeon (0.896 ± 0.082 and golden eagle (1.087 ± 0.074. It is concluded that the long-eared owl flight feather has more outstanding damping ability compared to the pigeon and golden eagle flight feather shaft. Consequently, the long-eared owl flight feathers can dissipate the vibration energy more effectively during the flying process based on the principle of damping mechanism, for the purpose of vibration attenuation and structure radiated noise reduction.

  8. Metals and trace elements in feathers: A geochemical approach to avoid misinterpretation of analytical responses.

    Science.gov (United States)

    Borghesi, Fabrizio; Migani, Francesca; Andreotti, Alessandro; Baccetti, Nicola; Bianchi, Nicola; Birke, Manfred; Dinelli, Enrico

    2016-02-15

    Assessing trace metal pollution using feathers has long attracted the attention of ecotoxicologists as a cost-effective and non-invasive biomonitoring method. In order to interpret the concentrations in feathers considering the external contamination due to lithic residue particles, we adopted a novel geochemical approach. We analysed 58 element concentrations in feathers of wild Eurasian Greater Flamingo Phoenicopterus roseus fledglings, from 4 colonies in Western Europe (Spain, France, Sardinia, and North-eastern Italy) and one group of adults from zoo. In addition, 53 elements were assessed in soil collected close to the nesting islets. This enabled to compare a wide selection of metals among the colonies, highlighting environmental anomalies and tackling possible causes of misinterpretation of feather results. Most trace elements in feathers (Al, Ce, Co, Cs, Fe, Ga, Li, Mn, Nb, Pb, Rb, Ti, V, Zr, and REEs) were of external origin. Some elements could be constitutive (Cu, Zn) or significantly bioaccumulated (Hg, Se) in flamingos. For As, Cr, and to a lesser extent Pb, it seems that bioaccumulation potentially could be revealed by highly exposed birds, provided feathers are well cleaned. This comprehensive study provides a new dataset and confirms that Hg has been accumulated in feathers in all sites to some extent, with particular concern for the Sardinian colony, which should be studied further including Cr. The Spanish colony appears critical for As pollution and should be urgently investigated in depth. Feathers collected from North-eastern Italy were the hardest to clean, but our methods allowed biological interpretation of Cr and Pb. Our study highlights the importance of external contamination when analysing trace elements in feathers and advances methodological recommendations in order to reduce the presence of residual particles carrying elements of external origin. Geochemical data, when available, can represent a valuable tool for a correct

  9. Keratin homogeneity in the tail feathers of Pavo cristatus and Pavo cristatus mut. alba

    OpenAIRE

    Pabisch, S.; Puchegger, S.; Kirchner, H.O.K.; Weiss, I.M.; Peterlik, H.

    2010-01-01

    The keratin structure in the cortex of peacocks? feathers is studied by X-ray diffraction along the feather, from the calamus to the tip. It changes considerably over the first 5?cm close to the calamus and remains constant for about 1?m along the length of the feather. Close to the tip, the structure loses its high degree of order. We attribute the X-ray patterns to a shrinkage of a cylindrical arrangement of ?-sheets, which is not fully formed initially. In the final structure, the crystall...

  10. A STATISTICAL STUDY OF TRANSVERSE OSCILLATIONS IN A QUIESCENT PROMINENCE

    Energy Technology Data Exchange (ETDEWEB)

    Hillier, A. [Kwasan and Hida Observatories, Kyoto University, Kyoto 607-8471 (Japan); Morton, R. J. [Mathematics and Information Science, Northumbria University, Pandon Building, Camden Street, Newcastle upon Tyne NE1 8ST (United Kingdom); Erdélyi, R., E-mail: andrew@kwasan.kyoto-u.ac.jp [Solar Physics and Space Plasma Research Centre (SP2RC), University of Sheffield, Hicks Building, Hounsfield Road, Sheffield S3 7RH (United Kingdom)

    2013-12-20

    The launch of the Hinode satellite has allowed for seeing-free observations at high-resolution and high-cadence making it well suited to study the dynamics of quiescent prominences. In recent years it has become clear that quiescent prominences support small-amplitude transverse oscillations, however, sample sizes are usually too small for general conclusions to be drawn. We remedy this by providing a statistical study of transverse oscillations in vertical prominence threads. Over a 4 hr period of observations it was possible to measure the properties of 3436 waves, finding periods from 50 to 6000 s with typical velocity amplitudes ranging between 0.2 and 23 km s{sup –1}. The large number of observed waves allows the determination of the frequency dependence of the wave properties and derivation of the velocity power spectrum for the transverse waves. For frequencies less than 7 mHz, the frequency dependence of the velocity power is consistent with the velocity power spectra generated from observations of the horizontal motions of magnetic elements in the photosphere, suggesting that the prominence transverse waves are driven by photospheric motions. However, at higher frequencies the two distributions significantly diverge, with relatively more power found at higher frequencies in the prominence oscillations. These results highlight that waves over a large frequency range are ubiquitous in prominences, and that a significant amount of the wave energy is found at higher frequency.

  11. A STATISTICAL STUDY OF TRANSVERSE OSCILLATIONS IN A QUIESCENT PROMINENCE

    International Nuclear Information System (INIS)

    Hillier, A.; Morton, R. J.; Erdélyi, R.

    2013-01-01

    The launch of the Hinode satellite has allowed for seeing-free observations at high-resolution and high-cadence making it well suited to study the dynamics of quiescent prominences. In recent years it has become clear that quiescent prominences support small-amplitude transverse oscillations, however, sample sizes are usually too small for general conclusions to be drawn. We remedy this by providing a statistical study of transverse oscillations in vertical prominence threads. Over a 4 hr period of observations it was possible to measure the properties of 3436 waves, finding periods from 50 to 6000 s with typical velocity amplitudes ranging between 0.2 and 23 km s –1 . The large number of observed waves allows the determination of the frequency dependence of the wave properties and derivation of the velocity power spectrum for the transverse waves. For frequencies less than 7 mHz, the frequency dependence of the velocity power is consistent with the velocity power spectra generated from observations of the horizontal motions of magnetic elements in the photosphere, suggesting that the prominence transverse waves are driven by photospheric motions. However, at higher frequencies the two distributions significantly diverge, with relatively more power found at higher frequencies in the prominence oscillations. These results highlight that waves over a large frequency range are ubiquitous in prominences, and that a significant amount of the wave energy is found at higher frequency

  12. Structural Color of Rock Dove’s Neck Feather

    Science.gov (United States)

    Nakamura, Eri; Yoshioka, Shinya; Kinoshita, Shuichi

    2008-12-01

    It is well known that some kinds of animal have surprisingly brilliant colors showing beautiful iridescence. These colors are called structural colors, and are thought to originate from optical interference caused by periodic microstructures that have sizes comparable with the wavelength of light. However, much larger structural modifications can also play an important role in the coloration mechanism. In this paper, we show through careful optical and structural investigations that the structural color of the neck feather of rock dove, Columba livia, has a very comprehensive mechanism: the thin-layer optical interference phenomenon fundamentally produces the iridescence, while the layer structure is accompanied by various kinds of larger-size structural modifications that control the angular range of the reflection. Further, it is found that the granules containing melanin pigment exist in a localized manner to effectively enhance the contrast of the color caused by optical interference.

  13. The chicken frizzle feather is due to an α-keratin (KRT75 mutation that causes a defective rachis.

    Directory of Open Access Journals (Sweden)

    Chen Siang Ng

    Full Text Available Feathers have complex forms and are an excellent model to study the development and evolution of morphologies. Existing chicken feather mutants are especially useful for identifying genetic determinants of feather formation. This study focused on the gene F, underlying the frizzle feather trait that has a characteristic curled feather rachis and barbs in domestic chickens. Our developmental biology studies identified defects in feather medulla formation, and physical studies revealed that the frizzle feather curls in a stepwise manner. The frizzle gene is transmitted in an autosomal incomplete dominant mode. A whole-genome linkage scan of five pedigrees with 2678 SNPs revealed association of the frizzle locus with a keratin gene-enriched region within the linkage group E22C19W28_E50C23. Sequence analyses of the keratin gene cluster identified a 69 bp in-frame deletion in a conserved region of KRT75, an α-keratin gene. Retroviral-mediated expression of the mutated F cDNA in the wild-type rectrix qualitatively changed the bending of the rachis with some features of frizzle feathers including irregular kinks, severe bending near their distal ends, and substantially higher variations among samples in comparison to normal feathers. These results confirmed KRT75 as the F gene. This study demonstrates the potential of our approach for identifying genetic determinants of feather forms.

  14. Two Categories of Apparent Tornado-like Prominences

    Science.gov (United States)

    Martin, Sara F.; Venkataramanasastry, Aparna

    2014-06-01

    Two categories of solar prominences have been described in the literature as having a pattern of mass motions and/or a shape similar to terrestrial tornados. We first identify the two categories associated with prominences in the historic literature and then show that counterparts do exist for both in recent literature but one has not been called a tornado prominence. One category described as being similar to tornados is associated with the barbs of quiescent filaments but barbs appear to have rotational motion only under special conditions. H alpha Doppler observations from Helio Research confirm that this category is an illusion in our mind’s eye resulting from counterstreaming in the large barbs of quiescent filaments. The second category is a special case of rotational motion occurring during the early stages of some erupting prominences, in recent years called the roll effect in erupting prominences. In these cases, the eruption begins with the sideways rolling of the top of a prominence. As the eruption proceeds the rolling motion propagates down one leg or both legs of an erupting prominence depending on whether the eruption is asymmetric or symmetric respectively. As an asymmetric eruption proceeds, the longer lasting leg becomes nearly vertical and has true rotational motion. If only this phase of the eruption was observed, as in the historic cases, it was called a tornado prominence and spectra recorded in these cases provide proof of the rotational motion. When one observes an entire eruption which exhibits the rolling motion, as accomplished at Helio Research, the similarity to a tornado is lost because the event as a whole has quite a different nature and the analogy to a terrestrial tornado not longer appears suitable or helpful in understanding the observed and deduced physical processes. Our conclusion is that there are no solar prominences with motions that are usefully described as tornado or tornado-like events aside from the fun of observing

  15. Feather damaging behaviour in parrots: A review with consideration of comparative aspects

    DEFF Research Database (Denmark)

    Van Zeeland, Yvonne R A; Spruit, Berry M; Rodenburg, T Bas

    2009-01-01

    similarities with behavioural disorders present in other bird species. Feather pecking (FP) in poultry is of particular interest in this case. Because of the major impacts on welfare and economy, the disorder has been thoroughly investigated. It has been shown that genetic, socio-environmental...... and neurobiological factors all play a role in FP. Several theories have been postulated about the different motivational systems that affect the behaviour, of which (redirected) foraging appears to be the most generally accepted. FDB may result from similar motivations and underlying mechanisms, but has also been......Feather damaging behaviour (also referred to as feather picking or feather plucking) is a behavioural disorder that is frequently encountered in captive parrots. This disorder has many characteristics that are similar to trichotillomania, an impulse control disorder in humans. Unfortunately...

  16. Vibrational spectroscopic analyses of unique yellow feather pigments (spheniscins) in penguins.

    Science.gov (United States)

    Thomas, Daniel B; McGoverin, Cushla M; McGraw, Kevin J; James, Helen F; Madden, Odile

    2013-06-06

    Many animals extract, synthesize and refine chemicals for colour display, where a range of compounds and structures can produce a diverse colour palette. Feather colours, for example, span the visible spectrum and mostly result from pigments in five chemical classes (carotenoids, melanins, porphyrins, psittacofulvins and metal oxides). However, the pigment that generates the yellow colour of penguin feathers appears to represent a sixth, poorly characterized class of feather pigments. This pigment class, here termed 'spheniscin', is displayed by half of the living penguin genera; the larger and richer colour displays of the pigment are highly attractive. Using Raman and mid-infrared spectroscopies, we analysed yellow feathers from two penguin species (king penguin, Aptenodytes patagonicus; macaroni penguin, Eudyptes chrysolophus) to further characterize spheniscin pigments. The Raman spectrum of spheniscin is distinct from spectra of other feather pigments and exhibits 17 distinctive spectral bands between 300 and 1700 cm(-1). Spectral bands from the yellow pigment are assigned to aromatically bound carbon atoms, and to skeletal modes in an aromatic, heterocyclic ring. It has been suggested that the penguin pigment is a pterin compound; Raman spectra from yellow penguin feathers are broadly consistent with previously reported pterin spectra, although we have not matched it to any known compound. Raman spectroscopy can provide a rapid and non-destructive method for surveying the distribution of different classes of feather pigments in the avian family tree, and for correlating the chemistry of spheniscin with compounds analysed elsewhere. We suggest that the sixth class of feather pigments may have evolved in a stem-lineage penguin and endowed modern penguins with a costly plumage trait that appears to be chemically unique among birds.

  17. Sexual dimorphism in melanin pigmentation, feather coloration and its heritability in the barn swallow (Hirundo rustica.

    Directory of Open Access Journals (Sweden)

    Nicola Saino

    Full Text Available Melanin is the main pigment in animal coloration and considerable variation in the concentrations of the two melanin forms (pheo- and eumlanin in pigmented tissues exists among populations and individuals. Melanin-based coloration is receiving increasing attention particularly in socio-sexual communication contexts because the melanocortin system has been hypothesized to provide a mechanistic basis for covariation between coloration and fitness traits. However, with few notable exceptions, little detailed information is available on inter-individual and inter-population variation in melanin pigmentation and on its environmental, genetic and ontogenetic components. Here, we investigate melanin-based coloration in an Italian population of a passerine bird, the barn swallow (Hirundo rustica rustica, its sex- and age-related variation, and heritability. The concentrations of eu- and pheomelanin in the throat (brown and belly (white-to-brownish feathers differed between sexes but not according to age. The relative concentration of either melanin (Pheo:Eu differed between sexes in throat but not in belly feathers, and the concentrations in males compared to females were larger in belly than in throat feathers. There were weak correlations between the concentrations of melanins within as well as among plumage regions. Coloration of belly feathers was predicted by the concentration of both melanins whereas coloration of throat feathers was only predicted by pheomelanin in females. In addition, Pheo:Eu predicted coloration of throat feathers in females and that of belly feathers in males. Finally, we found high heritability of color of throat feathers. Melanization was found to differ from that recorded in Hirundo rustica rustica from Scotland or from H. r. erythrogaster from North America. Hence, present results show that pigmentation strategies vary in a complex manner according to sex and plumage region, and also among geographical populations

  18. Drag Analysis of an Aircraft Wing Model withand without Bird Feather like Winglet

    OpenAIRE

    Altab Hossain; Ataur Rahman; A.K.M. P. Iqbal; M. Ariffin; M. Mazian

    2011-01-01

    This work describes the aerodynamic characteristic for aircraft wing model with and without bird feather like winglet. The aerofoil used to construct the whole structure is NACA 653-218 Rectangular wing and this aerofoil has been used to compare the result with previous research using winglet. The model of the rectangular wing with bird feather like winglet has been fabricated using polystyrene before design using CATIA P3 V5R13 software and finally fabricated in wood. Th...

  19. Feather mites (Acari, Astigmata) associated with birds in an Atlantic Forest fragment in Northeastern Brazil

    OpenAIRE

    Silva, HM; Hernandes, FA; Pichorim, M

    2015-01-01

    AbstractThe present study reports associations between feather mites (Astigmata) and birds in an Atlantic Forest fragment in Rio Grande do Norte state, in Brazil. In the laboratory, mites were collected through visual examination of freshly killed birds. Overall, 172 individuals from 38 bird species were examined, between October 2011 and July 2012. The prevalence of feather mites was 80.8%, corresponding to 139 infested individuals distributed into 30 species and 15 families of hosts. Fiftee...

  20. VARIANCE COMPONENTS AND SELECTION FOR FEATHER PECKING BEHAVIOR IN LAYING HENS

    OpenAIRE

    Su, Guosheng; Kjaer, Jørgen B.; Sørensen, Poul

    2005-01-01

    Variance components and selection response for feather pecking behaviour were studied by analysing the data from a divergent selection experiment. An investigation show that a Box-Cox transformation with power =-0.2 made the data be approximately normally distributed and fit best by the given model. Variance components and selection response were estimated using Bayesian analysis with Gibbs sampling technique. The total variation was rather large for the two traits in both low feather peckin...

  1. Microstructural tissue-engineering in the rachis and barbs of bird feathers.

    Science.gov (United States)

    Lingham-Soliar, Theagarten

    2017-03-27

    Feathers do not have to be especially strong but they do need to be stiff and at the same time resilient and to have a high work of fracture. Syncitial barbule fibres are the highest size-class of continuous filaments in the cortex of the rachis of the feather. However, the rachis can be treated as a generalized cone of rapidly diminishing volume. This means that hundreds of syncitial barbule fibres of the rachis may have to be terminated before reaching the tip - creating potentially thousands of inherently fatal crack-like defects. Here I report a new microstructural architecture of the feather cortex in which most syncitial barbule fibres deviate to the right and left edges of the feather rachis from far within its borders and extend into the barbs, side branches of the rachis, as continuous filaments. This novel morphology adds significantly to knowledge of β-keratin self-assembly in the feather and helps solve the potential problem of fatal crack-like defects in the rachidial cortex. Furthermore, this new complexity, consistent with biology's robust multi-functionality, solves two biomechanical problems at a stroke. Feather barbs deeply 'rooted' within the rachis are also able to better withstand the aerodynamic forces to which they are subjected.

  2. Diverse uses of feathers with emphasis on diagnosis of avian viral infections and vaccine virus monitoring

    Directory of Open Access Journals (Sweden)

    I Davidson

    2009-09-01

    Full Text Available The large amounts of feathers produced by the poultry industry, that is considered as a waste was explored for possible uses in various industries, such as meals for animals, biofuels, biodegradable plastic materials, combating water pollution and more. That review mentions these uses, but concentrate on the utilization of feathers for the diagnosis of viral infections and for monitoring vaccine viruses in chickens after vaccination. The viral diseases in which diagnosis using nucleic acids extracted from the feather shafts was described are, Marek's disease virus, circoviruses, chicken anemia virus, fowlpox virus, avian retroviruses, avian influenza virus and infectious laryngotracheitis virus. In two cases, of Marek's disease virus and of infectious laryngotracheitis virus, the differentiation of vaccine and wild-type viruses from feather shafts was made possible, thus allowing for monitoring the vaccination efficacy. The present review demonstrates also the stability of DNA viruses in feather shafts, and the possible evaluation of environmental dissemination of pathogens. When viruses are transmitted vertically, like in the cases of the retrovirus REV, a teratogenic effect on the development of feathers of the day-old newly hatched chick might occur in the case of avian influenza and the chicken anemia virus, which might indicate on a viral infection.

  3. Feather mites (Acari, Astigmata from Azorean passerines (Aves, Passeriformes: lower species richness compared to European mainland

    Directory of Open Access Journals (Sweden)

    Rodrigues Pedro

    2015-01-01

    Full Text Available Ten passerine species were examined on three islands of the Azores (North Atlantic during 2013 and 2014 in order to identify their feather mite assemblages. We recorded 19 feather mite species belonging to four families of the superfamily Analgoidea (Analgidae, Proctophyllodidae, Psoroptoididae and Trouessartiidae. A high prevalence of feather mite species was recorded on the majority of the examined host species. Only three passerine species (Sylvia atricapilla, Regulus regulus and Serinus canaria presented the same full complex of mite species as commonly occurs in the plumage of their closest relatives in continental Europe. Passer domesticus presented the same limited fauna of feather mites living in the plumage as do its co-specifics in continental Europe. Carduelis carduelis bears the same feather mite species as do most of its continental populations in Europe, but it lacks one mite species occurring on this host in Egypt. Turdus merula, Pyrrhula murina and Fringilla coelebs are missing several mite species common to their continental relatives. This diminution could be explained by the founder effect, whereby a limited number of colonizing individuals did not transport the full set of feather mite species, or by the extinction of some mite species after initially having reached the Azores. The only individual of Motacilla cinerea sampled in this study presented a new host record for the mite species Trouessartia jedliczkai.

  4. Feather development genes and associated regulatory innovation predate the origin of Dinosauria.

    Science.gov (United States)

    Lowe, Craig B; Clarke, Julia A; Baker, Allan J; Haussler, David; Edwards, Scott V

    2015-01-01

    The evolution of avian feathers has recently been illuminated by fossils and the identification of genes involved in feather patterning and morphogenesis. However, molecular studies have focused mainly on protein-coding genes. Using comparative genomics and more than 600,000 conserved regulatory elements, we show that patterns of genome evolution in the vicinity of feather genes are consistent with a major role for regulatory innovation in the evolution of feathers. Rates of innovation at feather regulatory elements exhibit an extended period of innovation with peaks in the ancestors of amniotes and archosaurs. We estimate that 86% of such regulatory elements and 100% of the nonkeratin feather gene set were present prior to the origin of Dinosauria. On the branch leading to modern birds, we detect a strong signal of regulatory innovation near insulin-like growth factor binding protein (IGFBP) 2 and IGFBP5, which have roles in body size reduction, and may represent a genomic signature for the miniaturization of dinosaurian body size preceding the origin of flight. © The Author 2014. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

  5. Amino acid neurotoxins in feathers of the Lesser Flamingo, Phoeniconaias minor.

    Science.gov (United States)

    Metcalf, J S; Banack, S A; Kotut, K; Krienitz, L; Codd, G A

    2013-01-01

    The Lesser Flamingo (Phoeniconaias minor) is known to use cyanobacteria (primarily Arthrospira) as a major food source in the East African Rift Valley lakes. Periodically, mass mortalities have occurred, associated with the cyanobacterial toxins (cyanotoxins), microcystins and anatoxin-a. Deposition of these cyanotoxins into P. minor feathers has been shown to occur, consistent with the presence of cyanotoxins in the livers, stomach and faecal contents after dietary intake. As cyanobacteria have been shown to also produce the neurotoxins β-N-methylamino-L-alanine (BMAA) and 2,4-diaminobutyric acid (DAB), stored wing feathers, previously recovered from flamingos which had been exposed to microcystins and anatoxin-a and had subsequently died, were analysed for these neurotoxic amino acids. Trace amounts of BMAA were detected in extracts from Lake Nakuru flamingo feathers, with DAB also present at concentrations between 3.5 and 8.5 μg g(-1) dry weight in feathers from both lakes. Toxin recovery by solid-phase extraction of feather digests was tested with spiked deuterated BMAA and showed good recovery when analysed by LC-MS/MS (80-94%). This is the first report of these neurotoxic amino acids in birds. We discuss the origin and significance of DAB, alongside other cyanotoxins of dietary origin, in the feathers of the Lesser Flamingo. Copyright © 2012 Elsevier Ltd. All rights reserved.

  6. ON THE MAGNETISM AND DYNAMICS OF PROMINENCE LEGS HOSTING TORNADOES

    International Nuclear Information System (INIS)

    Martínez González, M. J.; Ramos, A. Asensio; Arregui, I.; Collados, M.; Beck, C.; Rodríguez, J. de la Cruz

    2016-01-01

    Solar tornadoes are dark vertical filamentary structures observed in the extreme ultraviolet associated with prominence legs and filament barbs. Their true nature and relationship to prominences requires an understanding of their magnetic structure and dynamic properties. Recently, a controversy has arisen: is the magnetic field organized forming vertical, helical structures or is it dominantly horizontal? And concerning their dynamics, are tornadoes really rotating or is it just a visual illusion? Here we analyze four consecutive spectro-polarimetric scans of a prominence hosting tornadoes on its legs, which helps us shed some light on their magnetic and dynamical properties. We show that the magnetic field is very smooth in all the prominence, which is probably an intrinsic property of the coronal field. The prominence legs have vertical helical fields that show slow temporal variation that is probably related to the motion of the fibrils. Concerning the dynamics, we argue that (1) if rotation exists, it is intermittent, lasting no more than one hour, and (2) the observed velocity pattern is also consistent with an oscillatory velocity pattern (waves).

  7. ON THE MAGNETISM AND DYNAMICS OF PROMINENCE LEGS HOSTING TORNADOES

    Energy Technology Data Exchange (ETDEWEB)

    Martínez González, M. J.; Ramos, A. Asensio; Arregui, I.; Collados, M. [Instituto de Astrofísica de Canarias, Vía Láctea s/n, E-38205 La Laguna, Tenerife (Spain); Beck, C. [National Solar Observatory, Sacramento Peak P.O. Box 62, Sunspot, NM 88349 (United States); Rodríguez, J. de la Cruz [Institute for Solar Physics, Department of Astronomy, Stockholm University, Albanova University Center, SE-10691 Stockholm (Sweden)

    2016-07-10

    Solar tornadoes are dark vertical filamentary structures observed in the extreme ultraviolet associated with prominence legs and filament barbs. Their true nature and relationship to prominences requires an understanding of their magnetic structure and dynamic properties. Recently, a controversy has arisen: is the magnetic field organized forming vertical, helical structures or is it dominantly horizontal? And concerning their dynamics, are tornadoes really rotating or is it just a visual illusion? Here we analyze four consecutive spectro-polarimetric scans of a prominence hosting tornadoes on its legs, which helps us shed some light on their magnetic and dynamical properties. We show that the magnetic field is very smooth in all the prominence, which is probably an intrinsic property of the coronal field. The prominence legs have vertical helical fields that show slow temporal variation that is probably related to the motion of the fibrils. Concerning the dynamics, we argue that (1) if rotation exists, it is intermittent, lasting no more than one hour, and (2) the observed velocity pattern is also consistent with an oscillatory velocity pattern (waves).

  8. Solar Tornado Prominences: Plasma Motions Along Filament Barbs

    Science.gov (United States)

    Panasenco, Olga; Velli, Marco; Martin, Sara F.; Rappazzo, Franco

    2013-03-01

    Recent high-resolution observations from the Solar Dynamic Observatory (SDO) have reawakened interest in the old and fascinating phenomenon of solar tornado prominences. This class of prominences was first introduced by E. Pettit in 1932, who studied them over many years up to 1950. High resolution and high cadence multi-wavelength data obtained by SDO reveal that the tornado-like properties of these prominences are mainly an illusion due to projection effects. We show that counterstreaming plasma motions with projected velocities up to +/- 45 km/sec along the prominence spine and barbs create a tornado-like impression when viewed at the limb. We demonstrate that barbs are often rooted at the intersection between 4-5 supergranular cells. We discuss the observed oscillations along the vertical parts of barbs and whether they may be related to vortex flows coming from the convection downdrafts at the intersection of supergranules (and possibly smaller convective cells) in the photosphere and their entrained magnetic field. The unwinding of magnetic threads near the photosphere via reconnection might be a source of the waves which are observed as oscillations in prominence barbs.

  9. Sparkling feather reflections of a bird-of-paradise explained by finite-difference time-domain modeling.

    Science.gov (United States)

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

    2014-03-25

    Birds-of-paradise are nature's prime examples of the evolution of color by sexual selection. Their brilliant, structurally colored feathers play a principal role in mating displays. The structural coloration of both the occipital and breast feathers of the bird-of-paradise Lawes' parotia is produced by melanin rodlets arranged in layers, together acting as interference reflectors. Light reflection by the silvery colored occipital feathers is unidirectional as in a classical multilayer, but the reflection by the richly colored breast feathers is three-directional and extraordinarily complex. Here we show that the reflection properties of both feather types can be quantitatively explained by finite-difference time-domain modeling using realistic feather anatomies and experimentally determined refractive index dispersion values of keratin and melanin. The results elucidate the interplay between avian coloration and vision and indicate tuning of the mating displays to the spectral properties of the avian visual system.

  10. Reconnection–Condensation Model for Solar Prominence Formation

    Energy Technology Data Exchange (ETDEWEB)

    Kaneko, Takafumi [Institute for Space-Earth Environmental Research, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi 464-8601 (Japan); Yokoyama, Takaaki, E-mail: kaneko@isee.nagoya-u.ac.jp [Department of Earth and Planetary Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033 (Japan)

    2017-08-10

    We propose a reconnection–condensation model in which topological change in a coronal magnetic field via reconnection triggers radiative condensation, thereby resulting in prominence formation. Previous observational studies have suggested that reconnection at a polarity inversion line of a coronal arcade field creates a flux rope that can sustain a prominence; however, they did not explain the origin of cool dense plasmas of prominences. Using three-dimensional magnetohydrodynamic simulations, including anisotropic nonlinear thermal conduction and optically thin radiative cooling, we demonstrate that reconnection can lead not only to flux rope formation but also to radiative condensation under a certain condition. In our model, this condition is described by the Field length, which is defined as the scale length for thermal balance between radiative cooling and thermal conduction. This critical condition depends weakly on the artificial background heating. The extreme ultraviolet emissions synthesized with our simulation results have good agreement with observational signatures reported in previous studies.

  11. Static current-sheet models of quiescent prominences

    Science.gov (United States)

    Wu, F.; Low, B. C.

    1986-12-01

    A particular class of theoretical models idealize the prominence to be a discrete flat electric-current sheet suspended vertically in a potential magnetic field. The weight of the prominence is supported by the Lorentz force in the current sheet. These models can be extended to have curved electric-current sheets and to vary three-dimensionally. The equation for force balance is 1 over 4 pi (del times B) times Bdel p- p9 z=zero. Using Cartesian coordinates we take, for simplicity, a uniform gravity with constant acceleration g in the direction -z. If we are interested not in the detailed internal structure of the prominence, but in the global magnetic configuration around the prominence, we may take prominence plasma to be cold. Consideration is given to how such equilibrium states can be constructed. To simplify the mathematical problem, suppose there is no electric current in the atmosphere except for the discrete currents in the cold prominence sheet. Let us take the plane z =0 to be the base of the atmosphere and restrict our attention to the domain z greater than 0. The task we have is to solve for a magnetic field which is everywhere potential except on some free surface S, subject to suit able to boundary conditions. The surface S is determined by requiring that it possesses a discrete electric current density such that the Lorentz force on it is everywhere vertically upward to balance the weight of the material m(S). Since the magnetic field is potential in the external atmosphere, the latter is decoupled from the magnetic field and its plane parallel hydrostatic pressure and density can be prescribed.

  12. Solar Prominence Modelling and Plasma Diagnostics at ALMA Wavelengths

    Science.gov (United States)

    Rodger, Andrew; Labrosse, Nicolas

    2017-09-01

    Our aim is to test potential solar prominence plasma diagnostics as obtained with the new solar capability of the Atacama Large Millimeter/submillimeter Array (ALMA). We investigate the thermal and plasma diagnostic potential of ALMA for solar prominences through the computation of brightness temperatures at ALMA wavelengths. The brightness temperature, for a chosen line of sight, is calculated using the densities of electrons, hydrogen, and helium obtained from a radiative transfer code under non-local thermodynamic equilibrium (non-LTE) conditions, as well as the input internal parameters of the prominence model in consideration. Two distinct sets of prominence models were used: isothermal-isobaric fine-structure threads, and large-scale structures with radially increasing temperature distributions representing the prominence-to-corona transition region. We compute brightness temperatures over the range of wavelengths in which ALMA is capable of observing (0.32 - 9.6 mm), however, we particularly focus on the bands available to solar observers in ALMA cycles 4 and 5, namely 2.6 - 3.6 mm (Band 3) and 1.1 - 1.4 mm (Band 6). We show how the computed brightness temperatures and optical thicknesses in our models vary with the plasma parameters (temperature and pressure) and the wavelength of observation. We then study how ALMA observables such as the ratio of brightness temperatures at two frequencies can be used to estimate the optical thickness and the emission measure for isothermal and non-isothermal prominences. From this study we conclude that for both sets of models, ALMA presents a strong thermal diagnostic capability, provided that the interpretation of observations is supported by the use of non-LTE simulation results.

  13. Prominent crista terminalis mimicking a right atrial mass: case report

    Directory of Open Access Journals (Sweden)

    Lange Peter

    2010-10-01

    Full Text Available Abstract The crista terminalis is a normal anatomical structure within the right atrium that is not normally visualised in the standard views obtained while performing a transthoracic echocardiogram. In this case report, transthoracic echocardiography suggested the presence of a right atrial mass in a patient with end stage renal disease. However, subsequent transesophageal echocardiography revealed that the right atrial mass was actually a thick muscular bridge in the right atrium consistent with a prominent crista terminalis. An understanding of the anatomy and the echocardiographic appearance of a prominent crista terminalis will minimize the misdiagnosis of this structure avoiding unnecessary expensive additional tests.

  14. PATTERNS OF FLOWS IN AN INTERMEDIATE PROMINENCE OBSERVED BY HINODE

    International Nuclear Information System (INIS)

    Ahn, Kwangsu; Chae, Jongchul; Cao Wenda; Goode, Philip R.

    2010-01-01

    The investigation of plasma flows in filaments/prominences gives us clues to understanding their magnetic structures. We studied the patterns of flows in an intermediate prominence observed by Hinode/SOT. By examining a time series of Hα images and Ca II H images, we have found horizontal flows in the spine and vertical flows in the barb. Both of these flows have a characteristic speed of 10-20 km s -1 . The horizontal flows displayed counterstreaming. Our detailed investigation revealed that most of the moving fragments in fact reversed direction at the end point of the spine near a footpoint close to the associated active region. These returning flows may be one possible explanation of the well-known counterstreaming flows in prominences. In contrast, we have found vertical flows-downward and upward-in the barb. Most of the horizontal flows in the spine seem to switch into vertical flows when they approach the barb, and vice versa. We propose that the net force resulting from a small deviation from magnetohydrostatic equilibrium, where magnetic fields are predominantly horizontal, may drive these patterns of flow. In the prominence studied here, the supposed magnetohydrostatic configuration is characterized by magnetic field lines sagging with angles of 13 0 and 39 0 in the spine and the barb, respectively.

  15. The Most Prominent Roles of an ESP Teacher

    Science.gov (United States)

    Ghafournia, Narjes; Sabet, Shokoofeh Ahmadian

    2014-01-01

    One prominent feature of many ESP (English for Specific Purposes) courses, which make them rather different from EGP (English for General Purposes) courses, is the presence of adult learners, who are primary workers and secondary learners. As ESP is a highly learner-cantered approach, paying close attention to the multidimensional needs of…

  16. On Lyman-line asymmetries in quiescent prominences

    Czech Academy of Sciences Publication Activity Database

    Gunár, Stanislav; Heinzel, Petr; Anzer, U.; Schmieder, B.

    2008-01-01

    Roč. 490, č. 1 (2008), s. 307-313 ISSN 0004-6361 Grant - others:EU(XE) ESA-PECS project No. 98030 Institutional research plan: CEZ:AV0Z10030501 Keywords : Sun prominences * radiative transfer * line profiles Subject RIV: BN - Astronomy, Celestial Mechanics, Astrophysics Impact factor: 4.153, year: 2008

  17. Unintended exposure in radiotherapy: Identification of prominent causes

    International Nuclear Information System (INIS)

    Boadu, Mary; Rehani, Madan Mohan

    2009-01-01

    Background and purpose: Unintended exposures in radiotherapy are likely to occur when certain conditions that favour such exposures exist. Based on the frequency of occurrence of various causes of 100 events of unintended exposures in radiotherapy as derived from the analysis of published reports, a checklist for assessing the vulnerability of radiotherapy facilities for potential accidents has been prepared. The list presents items to be considered for safety critical assessments of a radiotherapy department for the improvement of patient safety and the entire radiotherapy processes. Materials and methods: The resources used for this paper consist of 100 unintended radiotherapy exposures and were derived from existing published reports. The analysis was performed by forming two templates: one consisting of 10 initiating events and another of 35 contributing factors. Results: Four most prominent initiating events were identified and together accounted for about 70% of all the unintended exposure events. Ten most prominent contributing factors were also identified and together accounted for about 70% of all the radiotherapy unintended exposure events covered under this study. Conclusion: With this knowledge of high frequency of occurrences, the identified four prominent initiating events and the 10 most prominent contributing factors must be checked and dealt with as a matter of priority when assessing the safety of a radiotherapy facility. A simple checklist for checking the quality assurance programmes of a radiotherapy department for every aspect of the design and delivery of radiation have been provided.

  18. Further Validation of the Coach Identity Prominence Scale

    Science.gov (United States)

    Pope, J. Paige; Hall, Craig R.

    2014-01-01

    This study was designed to examine select psychometric properties of the Coach Identity Prominence Scale (CIPS), including the reliability, factorial validity, convergent validity, discriminant validity, and predictive validity. Coaches (N = 338) who averaged 37 (SD = 12.27) years of age, had a mean of 13 (SD = 9.90) years of coaching experience,…

  19. Whole genome microarray analysis of chicken embryo facial prominences

    Czech Academy of Sciences Publication Activity Database

    Buchtová, Marcela; Kuo, W. P.; Nimmagadda, S.; Benson, S. L.; Geetha-Loganathan, P.; Logan, C.; Au-Yeung, T.; Chiang, E.; Fu, K.; Richman, J. M.

    2010-01-01

    Roč. 239, - (2010), s. 574-591 ISSN 1058-8388 Institutional research plan: CEZ:AV0Z50450515 Keywords : pharyngeal arch * mandibular arch * maxillary prominence Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 2.864, year: 2010

  20. Prominence modelling: from observed emission measures to temperature profiles

    Czech Academy of Sciences Publication Activity Database

    Anzer, U.; Heinzel, Petr

    2008-01-01

    Roč. 480, č. 2 (2008), s. 537-542 ISSN 0004-6361 Grant - others:EU(XE) ESA-PECS Project No. 98030 Institutional research plan: CEZ:AV0Z10030501 Keywords : Sun * prominences * transition region Subject RIV: BN - Astronomy, Celestial Mechanics, Astrophysics Impact factor: 4.153, year: 2008

  1. Holdaway's analysis of the nose prominence of an adult Nigerian ...

    African Journals Online (AJOL)

    The nose prominence was assessed using Holdaway's analysis. Twenty radiographs randomly selected, were retraced to assess for errors. Data analysis included descriptive statistics, Student's t‑tests and analysis of variance using the Statistical Package for Social Sciences. Results: The mean value recorded for the nose ...

  2. Eruptive prominences and long-delay geomagnetic storms

    International Nuclear Information System (INIS)

    Wright, C.S.

    1983-01-01

    The relationship between disappearing solar fragments and geomagnetic disturbances was investigated. It is shown that long-delay storms are associated with filaments well removed from the disc centre, and particularly in the case of large filaments and prominences, the proportion of events that produce long-delay storms increases with angular distance from the centre

  3. Cylindrical prominences and the magnetic influence of the photospheric boundary

    International Nuclear Information System (INIS)

    Lerche, I.; Chicago Univ., IL; Low, B.C.

    1980-01-01

    We construct exact, non-linear, solutions for an horizontal, cylindrical, current-carrying, prominence supported against solar gravity by the action of a Lorentz force. The solutions incorporate the photosphere boundary condition, proposed by van Tend and Kuperus (1978), and analyzed by them for line filaments. Our solutions have finite radius for the prominence material and, as well as satisfying the equations of magnetostatic equilibrium, they allow for the continuity of gas pressure, and of the normal and tangential components of magnetic field across the circular prominence boundary. We show that an infinity of solutions is possible and we illustrate the basic behavior by investigation of a special case. We also give a prescription for constructing equilibrium fields for any horizontal prominence with arbitrary cross-section and with an arbitrary external magnetic field. The prescription is ideally suited for numerical codes and we suggest that both the equilibrium of such shapes can easily be accomplished numerically together with their evolutionary history. (orig.)

  4. Lines of MgI Detected in Solar Prominences

    Czech Academy of Sciences Publication Activity Database

    Heinzel, Petr; Kupryakov, Yu. A.; Schwartz, P.

    2016-01-01

    Roč. 40, č. 1 (2016), s. 87-91 ISSN 1845-8319. [Hvar Astrophysical Colloquium /14./. Hvar, 26.09.2016-30.09.2016] Institutional support: RVO:67985815 Keywords : prominences * limb-flare * MgI emession Subject RIV: BN - Astronomy, Celestial Mechanics, Astrophysics

  5. Topics and topic prominence in two sign languages

    NARCIS (Netherlands)

    Kimmelman, V.

    2015-01-01

    In this paper we describe topic marking in Russian Sign Language (RSL) and Sign Language of the Netherlands (NGT) and discuss whether these languages should be considered topic prominent. The formal markers of topics in RSL are sentence-initial position, a prosodic break following the topic, and

  6. Multi-Wavelength Eclipse Observations of a Quiescent Prominence

    Czech Academy of Sciences Publication Activity Database

    Jejčič, S.; Heinzel, Petr; Zapiór, M.; Druckmüller, M.; Gunár, Stanislav; Kotrč, Pavel

    2014-01-01

    Roč. 289, č. 7 (2014), s. 2487-2501 ISSN 0038-0938 R&D Projects: GA ČR GAP209/12/0906 Institutional support: RVO:67985815 Keywords : eclipse observations * prominences * quiescent Subject RIV: BN - Astronomy, Celestial Mechanics, Astrophysics Impact factor: 4.039, year: 2014

  7. Electron densities in quiescent prominences derived from eclipse observations

    Czech Academy of Sciences Publication Activity Database

    Jejčič, S.; Heinzel, Petr

    2009-01-01

    Roč. 254, č. 1 (2009), s. 89-100 ISSN 0038-0938 Grant - others:EU(XE) ESA-PECS project No. 98030 Institutional research plan: CEZ:AV0Z10030501 Keywords : prominences quiescent * eclipse observations * visible spectrum Subject RIV: BN - Astronomy, Celestial Mechanics, Astrophysics Impact factor: 3.628, year: 2009

  8. Response of sheep fed on concentrate containing feather meal and supplemented with mineral Chromium

    Directory of Open Access Journals (Sweden)

    Yulistiani D

    2013-03-01

    Full Text Available A study was conducted to evaluate the effect of substitution of protein concentrate with feather meal supplemented with organic chromium mineral on performance of lambs. Twenty five male lambs were fed basal feed of fresh chopped king grass ad libitum and were allotted to either one of five different supplements (five dietary treatments: Control (C; 10% of protein in concentrate was substituted by feather meal (FM; 10% of protein in concentrate was substituted by feather meal supplemented with Cr yeast at 1.5 mg (FMCrOrg; 10% of protein in concentrate was substituted by feather meal supplemented with Cr inorganic which equal to the amount of Cr bound in yeast (FMCr; Concentrate control supplemented with 1.5 mg Cr yeast (CCrOrg. Cr-organic was synthesized by incorporating CrCl3 in fermented rice flour by Rhizopus sp. The mineral is mixed with feather meal as a mineral carrier. Sheep in all treatments received iso protein concentrate. Parameters observed were body weight change, feed consumption and nutrient digestibility. Results shows that there was no significant effect of diet treatments on average daily gain (ADG, dry matter consumption and feed conversion, with the average value of 75.4 gr/day; 74.9 g/BW0.75 and 9.9 respectively, However diet treatment of organic chromium and protein substitution with feather meal (FMCrOrg showed tendency of having higher ADG (83.57 g/h/d. Average nutrient digestibility of dry matter, organic matter and NDF were 68.7; 69.6 and 60.9%, respectively. However NDF digestibility of FMCrOrg tended to be higher than other treatment (67.0%. It is concluded that partial substitution of protein concentrate by feather meal and 1.5 mg Cr-organic supplementation did not affect sheep performance.

  9. Isotopic characterization of flight feathers in two pelagic seabirds: Sampling strategies for ecological studies

    Science.gov (United States)

    Wiley, Anne E.; Ostrom, Peggy H.; Stricker, Craig A.; James, Helen F.; Gandhi, Hasand

    2010-01-01

    We wish to use stable-isotope analysis of flight feathers to understand the feeding behavior of pelagic seabirds, such as the Hawaiian Petrel (Pterodroma sandwichensis) and Newell’s Shearwater (Puffinus auricularis newelli). Analysis of remiges is particularly informative because the sequence and timing of remex molt are often known. The initial step, reported here, is to obtain accurate isotope values from whole remiges by means of a minimally invasive protocol appropriate for live birds or museum specimens. The high variability observed in D13C and D15N values within a feather precludes the use of a small section of vane. We found the average range within 42 Hawaiian Petrel remiges to be 1.3‰ for both D13C and D15N and that within 10 Newell’s Shearwater remiges to be 1.3‰ and 0.7‰ for D13C and D15N, respectively. The D13C of all 52 feathers increased from tip to base, and the majority of Hawaiian Petrel feathers showed an analogous trend in D15N. Although the average range of DD in 21 Hawaiian Petrel remiges was 11‰, we found no longitudinal trend. We discuss influences of trophic level, foraging location, metabolism, and pigmentation on isotope values and compare three methods of obtaining isotope averages of whole feathers. Our novel barb-sampling protocol requires only 1.0 mg of feather and minimal preparation time. Because it leaves the feather nearly intact, this protocol will likely facilitate obtaining isotope values from remiges of live birds and museum specimens. As a consequence, it will help expand the understanding of historical trends in foraging behavior

  10. Operation Clean Feather: Reducing oil pollution in Newfoundland waters

    International Nuclear Information System (INIS)

    Chardine, J.W.; Pelly, G.

    1994-01-01

    Oil pollution of marine waters around Newfoundland, and particularly in the vicinity of Placentia Bay, is a frequent occurrence. Many oiled seabirds are found on beaches in the bay, particularly in winter. The most likely pollution sources are ship operators who dump waste oils from bilges and slop tanks. In an effort to reduce the chronic discharge of waste oil into Placentia Bay, and thus the incidence of bird oiling, Operation Clean Feather was launched in 1991-92 and consisted of weekly surveys of Placentia Bay beaches, sampling of oil from vessels using the bay and from oiled birds and beaches, and experimentation to determine possible recovery rates of birds oiled at sea. The operation was considered a success at a number of levels. Significant reductions in numbers of oiled birds were noted in both 1991 and 1992 compared to 1989 or 1990. Estimated oil-related mortality was reduced to ca 25% of levels seen in the two years prior to the operation. The operation also provided the opportunity to test and refine an organizational framework designed to deal with the problem of chronic oil pollution reports. Communication efforts heightened the awareness of the oil pollution problem in Newfoundland waters. These efforts included distribution of pamphlets in various languages to ship operators, describing the seriousness of oil-related marine bird mortality and warning of the substantial fines that can be imposed under the Canada Shipping Act. 6 refs., 3 figs., 1 tab

  11. Feather mites (Acari, Astigmata associated with birds in an Atlantic Forest fragment in Northeastern Brazil

    Directory of Open Access Journals (Sweden)

    HM Silva

    Full Text Available AbstractThe present study reports associations between feather mites (Astigmata and birds in an Atlantic Forest fragment in Rio Grande do Norte state, in Brazil. In the laboratory, mites were collected through visual examination of freshly killed birds. Overall, 172 individuals from 38 bird species were examined, between October 2011 and July 2012. The prevalence of feather mites was 80.8%, corresponding to 139 infested individuals distributed into 30 species and 15 families of hosts. Fifteen feather mite taxa could be identified to the species level, sixteen to the genus level and three to the subfamily level, distributed into the families Analgidae, Proctophyllodidae, Psoroptoididae, Pteronyssidae, Xolalgidae, Trouessartiidae, Falculiferidae and Gabuciniidae. Hitherto unknown associations between feather mites and birds were recorded for eleven taxa identified to the species level, and nine taxa were recorded for the first time in Brazil. The number of new geographic records, as well as the hitherto unknown mite-host associations, supports the high estimates of diversity for feather mites of Brazil and show the need for research to increase knowledge of plumicole mites in the Neotropical region.

  12. Sounds of Modified Flight Feathers Reliably Signal Danger in a Pigeon.

    Science.gov (United States)

    Murray, Trevor G; Zeil, Jochen; Magrath, Robert D

    2017-11-20

    In his book on sexual selection, Darwin [1] devoted equal space to non-vocal and vocal communication in birds. Since then, vocal communication has become a model for studies of neurobiology, learning, communication, evolution, and conservation [2, 3]. In contrast, non-vocal "instrumental music," as Darwin called it, has only recently become subject to sustained inquiry [4, 5]. In particular, outstanding work reveals how feathers, often highly modified, produce distinctive sounds [6-9], and suggests that these sounds have evolved at least 70 times, in many orders [10]. It remains to be shown, however, that such sounds are signals used in communication. Here we show that crested pigeons (Ochyphaps lophotes) signal alarm with specially modified wing feathers. We used video and feather-removal experiments to demonstrate that the highly modified 8 th primary wing feather (P8) produces a distinct note during each downstroke. The sound changes with wingbeat frequency, so that birds fleeing danger produce wing sounds with a higher tempo. Critically, a playback experiment revealed that only if P8 is present does the sound of escape flight signal danger. Our results therefore indicate, nearly 150 years after Darwin's book, that modified feathers can be used for non-vocal communication, and they reveal an intrinsically reliable alarm signal. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Fifty shades of white: how white feather brightness differs among species

    Science.gov (United States)

    Igic, Branislav; D'Alba, Liliana; Shawkey, Matthew D.

    2018-04-01

    White colouration is a common and important component of animal visual signalling and camouflage, but how and why it varies across species is poorly understood. White is produced by wavelength-independent and diffuse scattering of light by the internal structures of materials, where the degree of brightness is related to the amount of light scattered. Here, we investigated the morphological basis of brightness differences among unpigmented pennaceous regions of white body feathers across 61 bird species. Using phylogenetically controlled comparisons of reflectance and morphometric measurements, we show that brighter white feathers had larger and internally more complex barbs than duller white feathers. Higher brightness was also associated with more closely packed barbs and barbules, thicker and longer barbules, and rounder and less hollow barbs. Larger species tended to have brighter white feathers than smaller species because they had thicker and more complex barbs, but aquatic species were not significantly brighter than terrestrial species. As similar light scattering principals affect the brightness of chromatic signals, not just white colours, these findings help broaden our general understanding of the mechanisms that affect plumage brightness. Future studies should examine how feather layering on a bird's body contributes to differences between brightness of white plumage patches within and across species.

  14. Hidden keys to survival: the type, density, pattern and functional role of emperor penguin body feathers.

    Science.gov (United States)

    Williams, Cassondra L; Hagelin, Julie C; Kooyman, Gerald L

    2015-10-22

    Antarctic penguins survive some of the harshest conditions on the planet. Emperor penguins breed on the sea ice where temperatures drop below -40°C and forage in -1.8°C waters. Their ability to maintain 38°C body temperature in these conditions is due in large part to their feathered coat. Penguins have been reported to have the highest contour feather density of any bird, and both filoplumes and plumules (downy feathers) are reported absent in penguins. In studies modelling the heat transfer properties and the potential biomimetic applications of penguin plumage design, the insulative properties of penguin plumage have been attributed to the single afterfeather attached to contour feathers. This attribution of the afterfeather as the sole insulation component has been repeated in subsequent studies. Our results demonstrate the presence of both plumules and filoplumes in the penguin body plumage. The downy plumules are four times denser than afterfeathers and play a key, previously overlooked role in penguin survival. Our study also does not support the report that emperor penguins have the highest contour feather density. © 2015 The Author(s).

  15. k{sub 0}-INAA for determining chemical elements in bird feathers

    Energy Technology Data Exchange (ETDEWEB)

    Franca, Elvis J., E-mail: ejfranca@usp.b [CENA/USP, Centro de Energia Nuclear na Agricultura, Universidade of Sao Paulo, P.O. Box 97, 13400-970, Piracicaba, SP (Brazil); Fernandes, Elisabete A.N.; Fonseca, Felipe Y. [CENA/USP, Centro de Energia Nuclear na Agricultura, Universidade of Sao Paulo, P.O. Box 97, 13400-970, Piracicaba, SP (Brazil); Antunes, Alexsander Z. [IF, Instituto Florestal do Estado de Sao Paulo, Rua do Horto 931, Horto Florestal 02377-000, Sao Paulo, SP (Brazil); Bardini Junior, Claudiney; Bacchi, Marcio A.; Rodrigues, Vanessa S.; Cavalca, Isabel P.O. [CENA/USP, Centro de Energia Nuclear na Agricultura, Universidade of Sao Paulo, P.O. Box 97, 13400-970, Piracicaba, SP (Brazil)

    2010-10-11

    The k{sub 0}-method instrumental neutron activation analysis (k{sub 0}-INAA) was employed for determining chemical elements in bird feathers. A collection was obtained taking into account several bird species from wet ecosystems in diverse regions of Brazil. For comparison reason, feathers were actively sampled in a riparian forest from the Marins Stream, Piracicaba, Sao Paulo State, using mist nets specific for capturing birds. Biological certified reference materials were used for assessing the quality of analytical procedure. Quantification of chemical elements was performed using the k{sub 0}-INAA Quantu Software. Sixteen chemical elements, including macro and micronutrients, and trace elements, have been quantified in feathers, in which analytical uncertainties varied from 2% to 40% depending on the chemical element mass fraction. Results indicated high mass fractions of Br (max=7.9 mg kg{sup -1}), Co (max=0.47 mg kg{sup -1}), Cr (max=68 mg kg{sup -1}), Hg (max=2.79 mg kg{sup -1}), Sb (max=0.20 mg kg{sup -1}), Se (max=1.3 mg kg{sup -1}) and Zn (max=192 mg kg{sup -1}) in bird feathers, probably associated with the degree of pollution of the areas evaluated. In order to corroborate the use of k{sub 0}-INAA results in biomonitoring studies using avian community, different factor analysis methods were used to check chemical element source apportionment and locality clustering based on feather chemical composition.

  16. Head turning as a prominent motor symptom in status epilepticus.

    Science.gov (United States)

    Bauer, Gerhard; Broessner, Gregor; Unterberger, Iris; Walser, Gerald; Pfausler, Bettina; Trinka, Eugen

    2008-06-01

    Head and eye turning is frequently observed during seizures. Versions with tonic and/or clonic symptoms can be differentiated from smooth head deviations. Head turning as a prominent symptom of status epilepticus has not previously been reported. We present eight case reports, (7 women/1 man, mean age 41 years, median 41.5, range 10 to 74), of status epilepticus (SE), with head turning as a prominent motor symptom. Six were accompanied by continuous frontal, occipital and temporal ictal epileptiform discharges. Furthermore, two patients had absence status with rhythmic and clonic head versions. While the localizing significance of head turnings in SE is low, in our cases, the direction was away from the discharging hemisphere in all cases of focal SE regardless of whether the turning was classified as version (three cases) or deviation (three cases). In this small series of SE, the classical observation of a patient looking away from the discharging hemisphere is still valid.

  17. Non-LTE hydrogen-line formation in moving prominences

    Science.gov (United States)

    Heinzel, P.; Rompolt, B.

    1986-01-01

    The behavior of hydrogen-line brightness variations, depending on the prominence-velocity changes were investigated. By solving the NON-Local thermodynamic equilibrium (LTE) problem for hydrogen researchers determine quantitatively the effect of Doppler brightening and/or Doppler dimming (DBE, DDE) in the lines of Lyman and Balmer series. It is demonstrated that in low-density prominence plasmas, DBE in H alpha and H beta lines can reach a factor of three for velocities around 160 km/sec, while the L alpha line exhibits typical DDE. L beta brightness variations follow from a combined DBE in the H alpha and DDE in L alpha and L beta itself, providing that all relevant multilevel interlocking processes are taken into account.

  18. STRUCTURE OF PROMINENCE LEGS: PLASMA AND MAGNETIC FIELD

    Energy Technology Data Exchange (ETDEWEB)

    Levens, P. J.; Labrosse, N. [SUPA School of Physics and Astronomy, University of Glasgow, Glasgow, G12 8QQ (United Kingdom); Schmieder, B. [Observatoire de Paris, Meudon, F-92195 (France); Ariste, A. López, E-mail: p.levens.1@research.gla.ac.uk [Institut de Recherche en Astrophysique et Planétologie, Toulouse (France)

    2016-02-10

    We investigate the properties of a “solar tornado” observed on 2014 July 15, and aim to link the behavior of the plasma to the internal magnetic field structure of the associated prominence. We made multi-wavelength observations with high spatial resolution and high cadence using SDO/AIA, the Interface Region Imaging Spectrograph (IRIS) spectrograph, and the Hinode/Solar Optical Telescope (SOT) instrument. Along with spectropolarimetry provided by the Télescope Héliographique pour l’Etude du Magnétisme et des Instabilités Solaires telescope we have coverage of both optically thick emission lines and magnetic field information. AIA reveals that the two legs of the prominence are strongly absorbing structures which look like they are rotating, or oscillating in the plane of the sky. The two prominence legs, which are both very bright in Ca ii (SOT), are not visible in the IRIS Mg ii slit-jaw images. This is explained by the large optical thickness of the structures in Mg ii, which leads to reversed profiles, and hence to lower integrated intensities at these locations than in the surroundings. Using lines formed at temperatures lower than 1 MK, we measure relatively low Doppler shifts on the order of ±10 km s{sup −1} in the tornado-like structure. Between the two legs we see loops in Mg ii, with material flowing from one leg to the other, as well as counterstreaming. It is difficult to interpret our data as showing two rotating, vertical structures that are unrelated to the loops. This kind of “tornado” scenario does not fit with our observations. The magnetic field in the two legs of the prominence is found to be preferentially horizontal.

  19. Beat gestures and prosodic prominence: impact on learning

    OpenAIRE

    Kushch, Olga

    2018-01-01

    Previous research has shown that gestures are beneficial for language learning. This doctoral thesis centers on the effects of beat gestures– i.e., hand and arm gestures that are typically associated with prosodically prominent positions in speech - on such processes. Little is known about how the two central properties of beat gestures, namely how they mark both information focus and rhythmic positions in speech, can be beneficial for learning either a first or a second language. The main go...

  20. Observations of apparent superslow wave propagation in solar prominences

    Science.gov (United States)

    Raes, J. O.; Van Doorsselaere, T.; Baes, M.; Wright, A. N.

    2017-06-01

    Context. Phase mixing of standing continuum Alfvén waves and/or continuum slow waves in atmospheric magnetic structures such as coronal arcades can create the apparent effect of a wave propagating across the magnetic field. Aims: We observe a prominence with SDO/AIA on 2015 March 15 and find the presence of oscillatory motion. We aim to demonstrate that interpreting this motion as a magneto hydrodynamic (MHD) wave is faulty. We also connect the decrease of the apparent velocity over time with the phase mixing process, which depends on the curvature of the magnetic field lines. Methods: By measuring the displacement of the prominence at different heights to calculate the apparent velocity, we show that the propagation slows down over time, in accordance with the theoretical work of Kaneko et al. We also show that this propagation speed drops below what is to be expected for even slow MHD waves for those circumstances. We use a modified Kippenhahn-Schlüter prominence model to calculate the curvature of the magnetic field and fit our observations accordingly. Results: Measuring three of the apparent waves, we get apparent velocities of 14, 8, and 4 km s-1. Fitting a simple model for the magnetic field configuration, we obtain that the filament is located 103 Mm below the magnetic centre. We also obtain that the scale of the magnetic field strength in the vertical direction plays no role in the concept of apparent superslow waves and that the moment of excitation of the waves happened roughly one oscillation period before the end of the eruption that excited the oscillation. Conclusions: Some of the observed phase velocities are lower than expected for slow modes for the circumstances, showing that they rather fit with the concept of apparent superslow propagation. A fit with our magnetic field model allows for inferring the magnetic geometry of the prominence. The movie attached to Fig. 1 is available at http://www.aanda.org

  1. A genome-wide association study in a large F2-cross of laying hens reveals novel genomic regions associated with feather pecking and aggressive pecking behavior

    OpenAIRE

    Lutz, Vanessa; Stratz, Patrick; Preu?, Siegfried; Tetens, Jens; Grashorn, Michael A.; Bessei, Werner; Bennewitz, J?rn

    2017-01-01

    Background Feather pecking and aggressive pecking in laying hens are serious economic and welfare issues. In spite of extensive research on feather pecking during the last decades, the motivation for this behavior is still not clear. A small to moderate heritability has frequently been reported for these traits. Recently, we identified several single-nucleotide polymorphisms (SNPs) associated with feather pecking by mapping selection signatures in two divergent feather pecking lines. Here, we...

  2. Prominence and tornado dynamics observed with IRIS and THEMIS

    Science.gov (United States)

    Schmieder, Brigitte; Levens, Peter; Labrosse, Nicolas; Mein, Pierre; Lopez Ariste, Arturo; Zapior, Maciek

    2017-08-01

    Several prominences were observed during campaigns in September 2013 and July 2014 with the IRIS spectrometer and the vector magnetograph THEMIS (Tenerife). SDO/AIA and IRIS provided images and spectra of prominences and tornadoes corresponding to different physical conditions of the transition region between the cool plasma and the corona. The vector magnetic field was derived from THEMIS observations by using the He D3 depolarisation due to the magnetic field. The inversion code (PCA) takes into account the Hanle and Zeeman effects and allows us to compute the strength and the inclination of the magnetic field which is shown to be mostly horizontal in prominences as well as in tornadoes. Movies from SDO/AIA in 304 A and Hinode/SOT in Ca II show the highly dynamic nature of the fine structures. From spectra in Mg II and Si IV lines provided by IRIS and H-alpha observed by the Multi-channel Subtractive Double Pass (MSDP) spectrograph in the Meudon Solar Tower we derived the Doppler shifts of the fine structures and reconstructed the 3D structure of tornadoes. We conclude that the apparent rotation of AIA tornadoes is due to large-scale quasi-periodic oscillations of the plasma along more or less horizontal magnetic structures.

  3. Pyrolyzed feather fibers for adsorbent and high temperature applications

    Science.gov (United States)

    Senoz, Erman

    Chicken feather fibers (CFF) are problematic and costly for the poultry industry in terms of managing maintenance and disposal. Considering their great availability, low cost, and unique protein structure, CFF can be an environmentally friendly and bio-renewable candidate to replace petroleum products. CFF's low degradation and melting temperature render them useless at high temperatures. Pyrolysis methods were developed for CFF by using two temperature steps to convert them into high temperature resistant and adsorbent fibers while retaining their original physical appearance and affine dimensions. An intermolecular crosslinking mechanism in the first step of pyrolysis at 215 ºC for 24 h provided an intact fibrous structure with no subsequent melting. The evidence obtained from the thermal, bulk, and surface analysis techniques was indication of the simultaneous side chain degradation, polypeptide backbone scission, disulfide bond cleavage, and isopeptide crosslinking. The variation in the reaction kinetics of disulfide bond cleavage and isopeptide crosslinking played an important role in the melting transition. Consequently, long-lasting heat treatments below the melting point provided sufficient crosslinks in the protein matrix to keep the fibrous structure intact. Water-insoluble and crosslinked CFF reinforced the triglyceride-fatty acid based composites by providing a 15 fold increase in storage and tensile modulus at room temperature. These thermally stable fibers can be used instead of CFF in composites which may require high temperature compounding and molding processes. The second step of pyrolysis at 400--450 ºC for 1 h resulted in microporous fibers with a micropore volume of ˜0.18 cm3/g STP and with a narrower pore size distribution than commercial activated carbons through thermal degradation. Nearly all accessible pores in the microporous pyrolyzed chicken feather fibers (PCFF) had diameters less than 1 nm and therefore, showed a potential to be

  4. Genetic and phenotypic correlations between feather pecking and open-field reponse in laying hens at two different ages

    NARCIS (Netherlands)

    Rodenburg, T.B.; Buitenhuis, A.J.; Ask, B.; Uitdehaag, K.A.; Koene, P.; Poel, van der J.J.; Arendonk, van J.A.M.; Bovenhuis, H.

    2004-01-01

    The object of this research was to study the relationship between feather pecking and open-field activity in laying hens at two different ages. A population of 550 birds of a laying hen cross was subjected to an open-field test at 5 and 29 weeks of age and to a social feather pecking test at 6 and

  5. Keratin subsidies promote feather decomposition via an increase in keratin-consuming arthropods and microorganisms in bird breeding colonies.

    Science.gov (United States)

    Sugiura, Shinji; Masuya, Hayato

    2015-06-01

    Resource subsidies are well known to increase population densities of consumers. The decomposition process of these subsidised resources can be influenced by increasing consumer abundance. However, few studies have assessed whether resource subsidies can promote resource decomposition via a population increase in consumers. Here, we examined the effects of keratin subsidies on feather decomposition in egret and heron breeding colonies. Egrets and herons (Ardeidae) frequently breed in inland forests and provide large amounts of keratin materials to the forest floor in the form of feathers of chicks (that die). We compared the decrease in the weights of egret and heron feathers (experimentally placed on the forest floor) over a 12-month period among egret/heron breeding colonies (five sites) and areas outside of colonies (five sites) in central Japan. Of the feathers placed experimentally on forest floors, 92-97 % and 99-100 % in colonies and 47-50 % and 71-90 % in non-colony areas were decomposed after 4 and 12 months, respectively. Then, decomposition rates of feathers were faster in colonies than in areas outside of colonies, suggesting that keratin subsidies can promote feather decomposition in colonies. Field observations and laboratory experiments indicated that keratin-feeding arthropods and keratinophilic fungi played important roles in feather decomposition. Therefore, scavenging arthropods and keratinophilic fungi, which dramatically increased in egret and heron breeding colonies, could accelerate the decomposition of feathers supplied to the forest floor of colonies.

  6. Sparkling feather reflections of a bird-of-paradise explained by finite-difference time-domain modeling

    NARCIS (Netherlands)

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

    2014-01-01

    Birds-of-paradise are nature's prime examples of the evolution of color by sexual selection. Their brilliant, structurally colored feathers play a principal role in mating displays. The structural coloration of both the occipital and breast feathers of the bird-of-paradise Lawes' parotia is produced

  7. Reply to: “A response to some unwarranted criticisms of single-grain dating” by J.K. Feathers

    DEFF Research Database (Denmark)

    Thomsen, Kristina Jørkov; Murray, Andrew Sean; Buylaert, Jan-Pieter

    2017-01-01

    In the note “A response to some unwarranted criticisms of single-grain dating” Feathers raises many issues with both the approach and the conclusions of Thomsen et al. (2016). After careful consideration, we find we disagree with Feather's analysis and conclusions, and stand by the original concl...

  8. No effects of a feather mite on body condition, survivorship, or grooming behavior in the Seychelles warbler, Acrocephalus sechellensis

    NARCIS (Netherlands)

    Dowling, DK; Richardson, DS; Komdeur, J; Dowling, Damian K.; Richardson, David S.; Czeschlik, T.

    A common assumption of studies examining host-symbiont interactions is that all symbiotic organisms are parasitic. Feather mites are widespread symbionts of birds that do not appear to deplete the host of any vital resources. Instead they feed on the oily secretions that cover the feathers and the

  9. Variation in carbon and nitrogen stable isotope ratios in flight feathers of a moulting White-bellied Sunbird Cinnyris talatala

    CSIR Research Space (South Africa)

    Symes, CT

    2011-11-01

    Full Text Available The authors measured d13C and d15N isotope signatures in flight feathers of a White-bellied Sunbird to assess the value of using stable isotopes of feathers in avian dietary studies. Significant variation in d13C and d15N isotope values of flight...

  10. Amorphous diamond-structured photonic crystal in the feather barbs of the scarlet macaw.

    Science.gov (United States)

    Yin, Haiwei; Dong, Biqin; Liu, Xiaohan; Zhan, Tianrong; Shi, Lei; Zi, Jian; Yablonovitch, Eli

    2012-07-03

    Noniridescent coloration by the spongy keratin in parrot feather barbs has fascinated scientists. Nonetheless, its ultimate origin remains as yet unanswered, and a quantitative structural and optical description is still lacking. Here we report on structural and optical characterizations and numerical simulations of the blue feather barbs of the scarlet macaw. We found that the sponge in the feather barbs is an amorphous diamond-structured photonic crystal with only short-range order. It possesses an isotropic photonic pseudogap that is ultimately responsible for the brilliant noniridescent coloration. We further unravel an ingenious structural optimization for attaining maximum coloration apparently resulting from natural evolution. Upon increasing the material refractive index above the level provided by nature, there is an interesting transition from a photonic pseudogap to a complete bandgap.

  11. Keratin homogeneity in the tail feathers of Pavo cristatus and Pavo cristatus mut. alba.

    Science.gov (United States)

    Pabisch, S; Puchegger, S; Kirchner, H O K; Weiss, I M; Peterlik, H

    2010-12-01

    The keratin structure in the cortex of peacocks' feathers is studied by X-ray diffraction along the feather, from the calamus to the tip. It changes considerably over the first 5 cm close to the calamus and remains constant for about 1m along the length of the feather. Close to the tip, the structure loses its high degree of order. We attribute the X-ray patterns to a shrinkage of a cylindrical arrangement of β-sheets, which is not fully formed initially. In the final structure, the crystalline beta-cores are fixed by the rest of the keratin molecule. The hydrophobic residues of the beta-core are locked into a zip-like arrangement. Structurally there is no difference between the blue and the white bird. Copyright © 2010 Elsevier Inc. All rights reserved.

  12. Amorphous diamond-structured photonic crystal in the feather barbs of the scarlet macaw

    Science.gov (United States)

    Yin, Haiwei; Dong, Biqin; Liu, Xiaohan; Zhan, Tianrong; Shi, Lei; Zi, Jian; Yablonovitch, Eli

    2012-01-01

    Noniridescent coloration by the spongy keratin in parrot feather barbs has fascinated scientists. Nonetheless, its ultimate origin remains as yet unanswered, and a quantitative structural and optical description is still lacking. Here we report on structural and optical characterizations and numerical simulations of the blue feather barbs of the scarlet macaw. We found that the sponge in the feather barbs is an amorphous diamond-structured photonic crystal with only short-range order. It possesses an isotropic photonic pseudogap that is ultimately responsible for the brilliant noniridescent coloration. We further unravel an ingenious structural optimization for attaining maximum coloration apparently resulting from natural evolution. Upon increasing the material refractive index above the level provided by nature, there is an interesting transition from a photonic pseudogap to a complete bandgap. PMID:22615350

  13. Using an alternate light source to detect electrically singed feathers and hair in a forensic setting.

    Science.gov (United States)

    Viner, Tabitha C; Kagan, Rebecca A; Johnson, Jennifer L

    2014-01-01

    Mortality due to electrical injury in wildlife may occur in the form of lightning strike or power line contact. Evidence of electrical contact may be grossly obvious, with extensive singeing, curling, and blackening of feathers, fur, or skin. Occasionally, changes may be subtle, owing to lower current or reduced conductivity, making a definitive diagnosis of electrocution more difficult. We describe the use of an alternate light source in the examination of cases of lightning strike and power line contact in wildlife, and the enhanced detection of changes due to electrical currents in the hair and feathers of affected animals. Subtle changes in the wing feathers of 12 snow geese and 1 wolf that were struck by separate lightning events were made obvious by the use of an alternate light source. Similarly, this technique can be used to strengthen the evidence for power line exposure in birds. Published by Elsevier Ireland Ltd.

  14. Dinosaur evolution. A Jurassic ornithischian dinosaur from Siberia with both feathers and scales.

    Science.gov (United States)

    Godefroit, Pascal; Sinitsa, Sofia M; Dhouailly, Danielle; Bolotsky, Yuri L; Sizov, Alexander V; McNamara, Maria E; Benton, Michael J; Spagna, Paul

    2014-07-25

    Middle Jurassic to Early Cretaceous deposits from northeastern China have yielded varied theropod dinosaurs bearing feathers. Filamentous integumentary structures have also been described in ornithischian dinosaurs, but whether these filaments can be regarded as part of the evolutionary lineage toward feathers remains controversial. Here we describe a new basal neornithischian dinosaur from the Jurassic of Siberia with small scales around the distal hindlimb, larger imbricated scales around the tail, monofilaments around the head and the thorax, and more complex featherlike structures around the humerus, the femur, and the tibia. The discovery of these branched integumentary structures outside theropods suggests that featherlike structures coexisted with scales and were potentially widespread among the entire dinosaur clade; feathers may thus have been present in the earliest dinosaurs. Copyright © 2014, American Association for the Advancement of Science.

  15. Fracture toughness of zirconia ceramic crowns made by feather-edge tooth preparation design

    Directory of Open Access Journals (Sweden)

    Mirković Nemanja

    2012-01-01

    Full Text Available Background/Aim. Fracture toughness determines functional crown strenght and prevents damages on ceramics during mastication. There is a lack of relevant literature data about fracture toughness of crowns made by feather-edge preparation. Mechanical testing of ceramic samples is supposed to show if feather-edge tooth preparation is a successful method for making ceramic crowns without any risk of reduction of their mechanical properties. This research was done to establish effects of feather-edge tooth preparation on fracture toughness of single zirconia ceramic crowns. Methods. The research was performed as an experimental study. Sixty (60 ceramic crowns were made on non-carious extracted human premolars. Thirty (30 crowns were made on the basis of feather-edge preparation (experimental group I. The group II included 30 crowns made on 1 mm rounded shoulder. Crowns fabrication was executed on a copy mill production system “Zirkonzahn” (Zirkonzahn GMBH, Gais, Germany. The spherical compression test was used to determine fracture toughness, using 6 mm diameter ceramic ball. Fracture load for damaging ceramic crown was recorded on a universal testing machine - Zwick, type 1464, with the speed of 0.05 mm/min. Results. The results of this research introduced significant differences between fracture toughness of ceramic samples in every examined group. However, fracture toughness of crowns from both group was above 2 000 N, what was double beyond a recommended value. The mean value of fracture toughness in the feather-edge group was 2 090 N, and in shoulder group it was 2 214 N. Conclusion. This research showed a high fracture toughness of zirconia crowns made on feather-edge preparation. The examined crowns showed a fracture resistance at a sufficient distance in relation to the minimum values of functional loads. Further research of functional loads of these crown is necessary, as well as research of marginal adaptation of cemented crowns and

  16. Premature feather loss among common tern chicks in Ontario: the return of an enigmatic developmental anomaly

    Directory of Open Access Journals (Sweden)

    Jennifer M. Arnold

    2016-05-01

    Full Text Available In July 2014, we observed premature feather loss (PFL among non-sibling, common tern Sterna hirundo chicks between two and four weeks of age at Gull Island in northern Lake Ontario, Canada. Rarely observed in wild birds, to our knowledge PFL has not been recorded in terns since 1974, despite the subsequent banding of hundreds of thousands of tern chicks across North America alone. The prevalence, 5% of chicks (9/167, and extent of feather loss we report is more extreme than in previous reports for common terns but was not accompanied by other aberrant developmental or physical deformities. Complete feather loss from all body areas (wing, tail, head and body occurred over a period of a few days but all affected chicks appeared vigorous and quickly began to grow replacement feathers. All but one chick (recovered dead and submitted for post-mortem most likely fledged 10–20 days after normal fledging age. We found no evidence of feather dystrophy or concurrent developmental abnormalities unusual among affected chicks. Thus, the PFL we observed among common terns in 2014 was largely of unknown origin. There was striking temporal association between the onset of PFL and persistent strong southwesterly winds that caused extensive mixing of near-shore surface water with cool, deep lake waters. One hypothesis is that PFL may have been caused by unidentified pathogens or toxins welling up from these deep waters along the shoreline but current data are insufficient to test this. PFL was not observed among common terns at Gull Island in 2015, although we did observe similar feather loss in a herring gull Larus argentatus chick in that year. Comparison with sporadic records of PFL in other seabirds suggests that PFL may be a rare, but non-specific, response to a range of potential stressors. PFL is now known for gulls, penguins and terns.

  17. The dinosaurian origin of feathers: perspectives from dolphin (Cetacea) collagen fibers.

    Science.gov (United States)

    Lingham-Soliar, Theagarten

    2003-12-01

    The early origin of birds is a hotly disputed debate and may be broadly framed as a conflict between paleontologists and ornithologists. The paleontological emphasis has shifted from Archaeopteryx and its origins to recent finds of Cretaceous birds and "feathered" dinosaurs from China. The identification of alleged feathers has, however, relied principally on the visual image. Some workers have interpreted these integumentary structures as collagen fibers. To test the latter hypothesis, using light microscopy, collagen from the hypodermis (blubber) and subdermal connective tissue sheath was examined from a dolphin that had been buried for a year as part of an experiment. Within the blubber, toward the central thicker parts of the material, the collagen fibers had compacted and the three-dimensional latticework of normal blubber had more or less collapsed. Chromatographic analysis of the blubber revealed pronounced oxidation of the unsaturated lipids, probably accounting for the collapse of the latticework. Fibers normally bound together in bundles became separated into individual fibers or smaller bundles by degradation of the glue-like substance binding them together. These degraded collagen fibers show, in many instances, feather-like patterns, strikingly reminiscent of many of those identified as either "protofeathers" or "modern" feathers in dromaeosaurid dinosaurs. The findings throw serious doubt on the virtually complete reliance on visual image by supporters of the feathered dinosaur thesis and emphasize the need for more rigorous methods of identification using modern feathers as a frame of reference. Since collagen is the main fiber type found in most supporting tissues, the results have wide implications regarding the degradation and fossilization of vertebrate integument, such as that of the ichthyosaurs, dinosaurs and birds.

  18. Synthetic differential emission measure curves of prominence fine structures. II. The SoHO/SUMER prominence of 8 June 2004

    Czech Academy of Sciences Publication Activity Database

    Gunár, Stanislav; Parenti, S.; Anzer, U.; Heinzel, Petr; Vial, J. C.

    2011-01-01

    Roč. 535, November (2011), A122/1-A122/11 ISSN 0004-6361 R&D Projects: GA ČR GP205/09/P554; GA ČR GA205/09/1705; GA ČR GAP209/10/1706 Institutional research plan: CEZ:AV0Z10030501 Keywords : Sun * filaments * prominences Subject RIV: BN - Astronomy, Celestial Mechanics, Astrophysics Impact factor: 4.587, year: 2011

  19. Fault bars in bird feathers: mechanisms, and ecological and evolutionary causes and consequences.

    Science.gov (United States)

    Jovani, Roger; Rohwer, Sievert

    2017-05-01

    Fault bars are narrow malformations in feathers oriented almost perpendicular to the rachis where the feather vein and even the rachis may break. Breaks in the barbs and barbules result in small pieces of the feather vein being lost, while breaks in the rachis result in loss of the distal portion of the feather. Here, we provide a comprehensive review of 74 papers on fault bar formation in hopes of providing a clearer approach to their study. First, we review the evidence that the propensity to develop fault bars is modified by natural selection. Given that fault bars persist in the face of survival costs, we conclude that they must be an unfortunate consequence of some alternative adaptation that outweighs the fitness costs of fault bars. Second, we summarize evidence that the development of fault bars is triggered by psychological stress such as that of handling or predation attempts, and that they persist because the sudden contractions of the muscles in the feather follicle that control fright moults also causes the development of fault bars in growing feathers. Third, we review external and physiological (e.g. corticosterone) agents that may affect the likelihood that an acute stress will result in a growing feather exhibiting a fault bar. These modifying factors have often been treated as fundamental causes in the earlier literature on fault bars. Fourth, we then use this classification to propose a tentative model where fault bars of different severity (from light to severe) are the outcome of the interaction between the propensity to produce fault bars (which differs between species, individuals and feather follicles within individuals) and the intensity of the perturbation. This model helps to explain contradictory results in the literature, to identify gaps in our knowledge, and to suggest further studies. Lastly, we discuss ways in which better understanding of fault bars can inform us about other aspects of avian evolutionary ecology, such as the

  20. Feather bedding and childhood asthma associated with house dust mite sensitisation: a randomised controlled trial.

    Science.gov (United States)

    Glasgow, Nicholas J; Ponsonby, Anne-Louise; Kemp, Andrew; Tovey, Euan; van Asperen, Peter; McKay, Karen; Forbes, Samantha

    2011-06-01

    Observational studies report inverse associations between the use of feather upper bedding (pillow and/or quilt) and asthma symptoms but there is no randomised controlled trial (RCT) evidence assessing the role of feather upper bedding as a secondary prevention measure. To determine whether, among children not using feather upper bedding, a new feather pillow and feather quilt reduces asthma severity among house dust mite (HDM) sensitised children with asthma over a 1-year period compared with standard dust mite avoidance advice, and giving children a new mite-occlusive mattress cover. RCT. The Calvary Hospital in the Australian Capital Territory and the Children's Hospital at Westmead, Sydney, New South Wales. 197 children with HDM sensitisation and moderate to severe asthma. Intervention New upper bedding duck feather pillow and quilt and a mite-occlusive mattress cover (feather) versus standard care and a mite-occlusive mattress cover (standard). The proportion of children reporting four or more episodes of wheeze in the past year; an episode of speech-limiting wheeze; or one or more episodes of sleep disturbance caused by wheezing; and spirometry with challenge testing. Statistical analysis included multiple logistic and linear regression. No differences between groups were found for primary end points--frequent wheeze (OR 1.51, 95% CI 0.83 to 2.76, p=0.17), speech-limiting wheeze (OR 0.70, 95% CI 0.32 to 1.48, p=0.35), sleep disturbed because of wheezing (OR 1.17, 95% CI 0.64 to 2.13, p=0.61) or for any secondary end points. Secondary analyses indicated the intervention reduced the risk of sleep being disturbed because of wheezing and severe wheeze to a greater extent for children who slept supine. No differences in respiratory symptoms or lung function were observed 1 year after children with moderate-severe asthma and HDM sensitisation were given a mite-occlusive mattress cover and then received either feather upper bedding (pillow and quilt) or standard

  1. ARE GIANT TORNADOES THE LEGS OF SOLAR PROMINENCES?

    Energy Technology Data Exchange (ETDEWEB)

    Wedemeyer, Sven; Scullion, Eamon; Rouppe van der Voort, Luc; Bosnjak, Antonija [Institute of Theoretical Astrophysics, University of Oslo, P.O. Box 1029 Blindern, NO-0315 Oslo (Norway); Antolin, Patrick, E-mail: sven.wedemeyer@astro.uio.no [Centre for Mathematical Plasma Astrophysics, Department of Mathematics, KU Leuven, Celestijnenlaan 200B, bus 2400, B-3001 Leuven (Belgium)

    2013-09-10

    Observations in the 171 A channel of the Atmospheric Imaging Assembly of the space-borne Solar Dynamics Observatory show tornado-like features in the atmosphere of the Sun. These giant tornadoes appear as dark, elongated, and apparently rotating structures in front of a brighter background. This phenomenon is thought to be produced by rotating magnetic field structures that extend throughout the atmosphere. We characterize giant tornadoes through a statistical analysis of properties such as spatial distribution, lifetimes, and sizes. A total number of 201 giant tornadoes are detected in a period of 25 days, suggesting that, on average, about 30 events are present across the whole Sun at a time close to solar maximum. Most tornadoes appear in groups and seem to form the legs of prominences, thus serving as plasma sources/sinks. Additional H{alpha} observations with the Swedish 1 m Solar Telescope imply that giant tornadoes rotate as a structure, although they clearly exhibit a thread-like structure. We observe tornado groups that grow prior to the eruption of the connected prominence. The rotation of the tornadoes may progressively twist the magnetic structure of the prominence until it becomes unstable and erupts. Finally, we investigate the potential relation of giant tornadoes to other phenomena, which may also be produced by rotating magnetic field structures. A comparison to cyclones, magnetic tornadoes, and spicules implies that such events are more abundant and short-lived the smaller they are. This comparison might help to construct a power law for the effective atmospheric heating contribution as a function of spatial scale.

  2. ARE GIANT TORNADOES THE LEGS OF SOLAR PROMINENCES?

    International Nuclear Information System (INIS)

    Wedemeyer, Sven; Scullion, Eamon; Rouppe van der Voort, Luc; Bosnjak, Antonija; Antolin, Patrick

    2013-01-01

    Observations in the 171 Å channel of the Atmospheric Imaging Assembly of the space-borne Solar Dynamics Observatory show tornado-like features in the atmosphere of the Sun. These giant tornadoes appear as dark, elongated, and apparently rotating structures in front of a brighter background. This phenomenon is thought to be produced by rotating magnetic field structures that extend throughout the atmosphere. We characterize giant tornadoes through a statistical analysis of properties such as spatial distribution, lifetimes, and sizes. A total number of 201 giant tornadoes are detected in a period of 25 days, suggesting that, on average, about 30 events are present across the whole Sun at a time close to solar maximum. Most tornadoes appear in groups and seem to form the legs of prominences, thus serving as plasma sources/sinks. Additional Hα observations with the Swedish 1 m Solar Telescope imply that giant tornadoes rotate as a structure, although they clearly exhibit a thread-like structure. We observe tornado groups that grow prior to the eruption of the connected prominence. The rotation of the tornadoes may progressively twist the magnetic structure of the prominence until it becomes unstable and erupts. Finally, we investigate the potential relation of giant tornadoes to other phenomena, which may also be produced by rotating magnetic field structures. A comparison to cyclones, magnetic tornadoes, and spicules implies that such events are more abundant and short-lived the smaller they are. This comparison might help to construct a power law for the effective atmospheric heating contribution as a function of spatial scale

  3. Perceptions of Social Responsibility of Prominent Animal Welfare Groups.

    Science.gov (United States)

    Widmar, Nicole J Olynk; Morgan, Carissa J; Croney, Candace C

    2018-01-01

    Nonhuman animal welfare is an increasingly important component of consumer expectations of corporate social responsibility (CSR). The extent to which prominent animal welfare or protection organizations may influence people's perceptions of food industry CSR may be related to an organization's perceived social responsibility. Data from an online survey of 300 U.S. residents were used to explore relationships between demographics/lifestyle choices and perceptions of prominent animal welfare organizations (using best-worst scaling methodology). Overall, the American Society for the Prevention of Cruelty to Animals was perceived to be the most socially responsible organization analyzed, followed by the Humane Society of the United States and the American Humane Association (AHA). Results suggest that the perceived social responsibility of animal protection organizations in this study was not strongly linked to personally (financially) supporting them, with 2 exceptions: the perceptions of People for the Ethical Treatment of Animals and AHA. Improved understanding of the perception of animal welfare or protection organizations can inform decision making by organizations interested in furthering animal welfare causes.

  4. Word-level prominence in Persian: An Experimental Study.

    Science.gov (United States)

    Sadeghi, Vahid

    2017-12-01

    Previous literature on the phonetics of stress in Persian has reported that fundamental frequency is the only reliable acoustic correlate of stress, and that stressed and unstressed syllables are not differentiated from each other in the absence of accentuation. In this study, the effects of lexical stress on duration, overall intensity and spectral tilt were examined in Persian both in the accented and unaccented conditions. Results showed that syllable duration is consistently affected by stress in Persian in both the accented and unaccented conditions across all vowel types. Unlike duration, the results for overall intensity and spectral tilt were significant only in the accented condition, suggesting that measures of intensity are not a correlate of stress in Persian but they are mainly caused by the presence of a pitch movement. The findings are phonologically interpreted as suggesting that word-level prominence in Persian is typologically similar to 'stress accent' languages, in which multiple phonetic cues are used to signal the prominence contrast in the accented condition, and stressed and unstressed syllables are different from each other even when the word is not pitch-accented.

  5. Magnetic field re-arrangement after prominence eruption

    International Nuclear Information System (INIS)

    Kopp, R.A.; Poletto, G.

    1986-01-01

    It has long been known that magnetic reconnection plays a fundamental role in a variety of solar events. Although mainly invoked in flare problems, large-scale loops interconnecting active regions, evolving coronal hole boundaries, the solar magnetic cycle itself, provide different evidence of phenomena which involve magnetic reconnection. A further example might be given by the magnetic field rearrangement which occurs after the eruption of a prominence. Since most often a prominence reforms after its disappearance and may be observed at about the same position it occupied before erupting, the magnetic field has to undergo a temporary disruption to relax back, via reconnection, to a configuration similar to the previous one. The above sequence of events is best observable in the case of two-ribbon (2-R) flares but most probably is associated with all filament eruptions. Even if the explanation of the magnetic field rearrangement after 2-R flares in terms of reconnection is generally accepted, the lack of a three-dimensional model capable of describing the field reconfiguration, has prevented, up to now, a thorough analysis of its topology as traced by Hα/x-ray loops. The purpose of the present work is to present a numerical technique which enables one to predict and visualize the reconnected configuration, at any time t, and therefore allows one to make a significant comparison of observations and model predictions throughout the whole process. 5 refs., 3 figs

  6. Physics of solar prominences. Proceedings of the Colloquium, Oslo, Norway, August 14-18, 1978

    Energy Technology Data Exchange (ETDEWEB)

    Jensen, E; Maltby, P

    1979-01-01

    These papers deal with recent theoretical and observational studies of the physics of solar prominences. Specific topics include reviews of prominence spectra and their interpretation, polarimetric observations and magnetic-field determination in prominences, observations of the prominence-corona interface, theories on the formation and stability of quiescent prominences, prominence classifications, observations of active prominences, observations and interpretations of coronal manifestations of eruptive prominences, and models of prominence structure and dynamics. Other contributions discuss simultaneous observations of Ca II and hydrogen Balmer lines in quiescent prominences, recent results in quiescent-prominence spectroscopy, the solar helium abundance obtained from optical spectra of quiescent prominences, and Stokes polarimetry of quiescent prominences in the He I D3 line. Magnetic-field determination based on the Hanle effect is also examined, along with the orientation of prominence microstructure relative to magnetic-field direction, radio observations of quiescent-prominence filaments at centimeter and millimeter wavelengths, EUV observations of filaments, and a magnetic-field reconnection model of quiescent prominences.

  7. Automatic detection of prominence (as defined by listeners' judgements) in read aloud Dutch sentences

    NARCIS (Netherlands)

    Streefkerk, B.M.; Pols, L.C.W.; ten Bosch, L.F.M.

    1998-01-01

    This paper describes a first step towards the automatic classification of prominence (as defined by native listeners). As a result of a listening experiment each word in 500 sentences was marked with a rating scale between `0' (non-prominent) and `10' (very prominent). These prominence labels are

  8. The Structure of the Water-Holding Feathers of the Namaqua ...

    African Journals Online (AJOL)

    The barbule is solid, consisting of three layers, and bears a number of appendages at its distal end, where it is more rounded in transverse section. The uncoiling of barbules from the abdominal feathers on contact with water may be initiated by water uptake and further facilitated by the number of helical coils at the base of ...

  9. Kingfisher feathers--colouration by pigments, spongy nanostructures and thin films.

    Science.gov (United States)

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

    2011-12-01

    The colours of the common kingfisher, Alcedo atthis, reside in the barbs of the three main types of feather: the orange breast feathers, the cyan back feathers and the blue tail feathers. Scanning electron microscopy showed that the orange barbs contain small pigment granules. The cyan and blue barbs contain spongy nanostructures with slightly different dimensions, causing different reflectance spectra. Imaging scatterometry showed that the pigmented barbs create a diffuse orange scattering and the spongy barb structures create iridescence. The extent of the angle-dependent light scattering increases with decreasing wavelength. All barbs have a cortical envelope with a thickness of a few micrometres. The reflectance spectra of the cortex of the barbs show oscillations when measured from small areas, but when measured from larger areas the spectra become wavelength independent. This can be directly understood with thin film modelling, assuming a somewhat variable cortex thickness. The cortex reflectance appears to be small but not negligible with respect to the pigmentary and structural barb reflectance.

  10. Using Pb-Al ratios to discriminate between internal and external deposition of Pb in feathers.

    Science.gov (United States)

    Cardiel, Iris E; Taggart, Mark A; Mateo, Rafael

    2011-05-01

    Feathers provide a potentially useful biomonitoring option in studies regarding pollution exposure in avian species. However, they must be used with care because the complex, fine structure is highly prone to accumulating surface contamination. This may therefore give a misleading indication of pollutant intake in the animal. Here, data are presented for 4 large scavenging raptor species collected in Spain, and analyses are undertaken on feather barbs and rachis for both Pb and Al concentrations. Aluminium levels are used as a marker of surface contamination by inorganic particulate material. Despite using a thorough washing technique, feather barbs showed significantly higher levels of Pb than did the rachis for all 4 species studied. We also observed a significant correlation (r=0.782, pbarbs, whilst rachis Al levels were below our detection limit in all samples analysed. Results indicate that the rachis would provide more representative data as regards Pb (or other heavy metal) uptake and tissue deposition within bird tissues during the period of feather growth. As such, data would be more toxicologically relevant. Copyright © 2011 Elsevier Inc. All rights reserved.

  11. 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.

  12. Effect of dietary substitution of feather meal for fish meal on the ...

    African Journals Online (AJOL)

    Also significant differences (p<0.05) were observed in daily feed intake, daily weight gain and feed cost/kg weight gain. Considering the results of final live weight and daily weight gain, it appeared that the 7.5% level of FEM is the optimal replacement level for FM. Keywords: Feather meal, fishmeal, poultry feed, broiler chick ...

  13. New species of the feather mite subfamily Pterodectinae (Astigmata, Proctophyllodidae) from passerines in Senegal

    Czech Academy of Sciences Publication Activity Database

    Mironov, S. V.; Literák, I.; Čapek, Miroslav; Koubek, Petr

    2010-01-01

    Roč. 55, č. 4 (2010), s. 399-413 ISSN 1230-2821 R&D Projects: GA AV ČR IAA601690901 Institutional research plan: CEZ:AV0Z60930519 Keywords : Feather mites * systematics * Senegal * Passeriformes * Proctophyllodidae Subject RIV: EG - Zoology Impact factor: 1.144, year: 2010

  14. Prenatal light exposure affects early feather-pecking behaviour in the domestic chick

    NARCIS (Netherlands)

    Riedstra, B; Groothuis, TGG

    Recently we proposed that early feather pecking is a form of social exploration. Social recognition, important for exploration, is a lateralized function in the domestic chick. Lateralization of functions can be influenced by light exposure late in embryonic development. Therefore, we investigated

  15. Concentration of trace elements in feathers of three Antarctic penguins: Geographical and interspecific differences

    Energy Technology Data Exchange (ETDEWEB)

    Jerez, Silvia [Area de Toxicologia, Facultad de Veterinaria, Universidad de Murcia, Campus de Espinardo, 30100 Murcia (Spain); Motas, Miguel, E-mail: motas@um.es [Area de Toxicologia, Facultad de Veterinaria, Universidad de Murcia, Campus de Espinardo, 30100 Murcia (Spain); Palacios, Maria Jose; Valera, Francisco [Departamento de Ecologia Funcional y Evolutiva, Estacion Experimental de Zonas Aridas, CSIC, Carretera de Sacramento s/n, 04120 La Canada de San Urbano, Almeria (Spain); Cuervo, Jose Javier; Barbosa, Andres [Departamento de Ecologia Funcional y Evolutiva, Estacion Experimental de Zonas Aridas, CSIC, Carretera de Sacramento s/n, 04120 La Canada de San Urbano, Almeria (Spain); Departamento de Ecologia Evolutiva, Museo Nacional de Ciencias Naturales, CSIC, C/Jose Gutierrez Abascal 2, 28006 Madrid (Spain)

    2011-10-15

    Antarctica is often considered as one of the last pristine regions, but it could be affected by pollution at global and local scale. Concentrations of Al, Cr, Mn, Fe, Ni, Cu, Zn, As, Se, Cd and Pb were determinated by ICP-MS in feathers (n = 207 individuals) of gentoo, chinstrap and Adelie penguin collected in 8 locations throughout the Antarctic Peninsula (2006-2007). The highest levels of several elements were found in samples from King George Island (8.08, 20.29 and 1.76 {mu}g g{sup -1} dw for Cr, Cu and Pb, respectively) and Deception Island (203.13, 3.26 and 164.26 {mu}g g{sup -1} dw for Al, Mn and Fe, respectively), where probably human activities and large-scale transport of pollutants contribute to increase metal levels. Concentrations of Cr, Mn, Cu, Se or Pb, which are similar to others found in different regions of the world, show that some areas in Antarctica are not utterly pristine. - Highlights: > We study levels of trace elements in feathers of Antarctic penguins. > Eight different rookeries throughout the Antarctic Peninsula were sampled. > Interspecific (gentoo, chinstrap, Adelie) and geographical differences were tested. > Relatively high metal levels were found in areas with major human presence. > Penguin feather can be useful for metals monitoring in the Antarctic environment. - Trace element levels in feathers of three penguin species from the Antarctic Peninsula indicate the presence of pollution in certain locations.

  16. Feather conditions and clinical scores as indicators of broilers welfare at the slaughterhouse.

    Science.gov (United States)

    Saraiva, S; Saraiva, C; Stilwell, G

    2016-08-01

    The objective of this study was to evaluate the welfare of 64 different broiler farms on the basis of feather conditions and clinical scores measures collected at the slaughterhouse. A 3-point scale (0, 1 or 2) was used to classify dirty feathers, footpad dermatitis and hock burns measures, and a 2-point scale (present or absent) was used to classify breast burns, breast blisters and breast ulcer measures. Flocks were allocated into three body weight (BW) classes (A, B, C): class A (light) ≥1.43 and ≤1.68kg, class B (medium) ≥1.69 and ≤1.93kg; class C (heavy) ≥1.94 and ≤2.41kg. The absence of hock burns was more common in class A, while mild hock burns was more common in class B flocks. Breast ulcer was observed in class C flocks. The association observed for mild hock burns, breast burns and severe footpad dermatitis can indicate a simultaneous occurrence of these painful lesions. Very dirty feathers and severe footpad dermatitis relationship suggest litter humidity to be the common underlying cause. In conclusion, it was shown that clinical indicators can be used at the slaughterhouse to identify welfare problems. In the studied flocks, footpad dermatitis, feather conditions and hock burns were the main restrictions for good welfare and should be considered significant welfare indicators of the on-farm rearing conditions. Copyright © 2016 Elsevier Ltd. All rights reserved.

  17. Hair and feathers as indicator of internal contamination of 210Po and 210Pb

    Energy Technology Data Exchange (ETDEWEB)

    Holm, E. (ed.); Gwynn, J.; Zaborska, A.; Gaefvert, T. (Norwegian Radiation Protection Authority (Norway)); Roos, P. (Technical Univ. of Denmark, Risoe National Lab. for Sustainable Energy, Roskilde (Denmark)); Henricsson, F. (Lund Univ., Lund (Sweden))

    2010-03-15

    The activities of the NKS-B HAIRPOL project is summarised in this report. The objective was to investigate if hair and feathers were suitable matrices for the estimation of the intake of 210Po. Human hair from people of different sex and age was analysed for 210Po showing concentrations between 0.4 to 11 Bq/kg dry weight. Samples from horses, mane, fur and tail showed concentration from 6 to 17 Bq/kg with no significant difference between the different sample types. Musk ox from Greenland showed much higher concentrations since the animal has to graze a large surface. In fur the concentration was 260 Bq/kg. A considerable fraction of the total 210Po in this animal is contained in the hair. Also different organs were analysed and the highest concentration was found in kidney, 2 700 Bq/kg. The 210Pb concentration in hair was estimated to about 20 Bq/kg. Three different seabirds from Svalbard were analysed. Feathers from all three seabird species show increasing activity concentrations of 210Po and 210Pb from the base to the tip of the feather, but it was difficult to relate feather concentrations to muscle concentrations due to a number of complicating factors. (author)

  18. The feather damaging Grey parrot: an analysis of its behaviour and needs

    NARCIS (Netherlands)

    van Zeeland, Y.R.A.

    2013-01-01

    With an estimated prevalence of 10-15%, feather damaging behaviour (FDB) is a common behavioural disorder in captive parrots (in particular Grey parrots, the species studied in this thesis) that may have aesthetic, medical and welfare consequences and often results in relinquishment or euthanasia.

  19. Birds of a Feather Don't Always Flock Together : User Problems in ...

    African Journals Online (AJOL)

    Birds of a Feather Don't Always Flock Together : User Problems in Identifying ... for Advanced Learners and Oxford Advanced Learner's Dictionary) revealed a lack ... This paper is based on 14 of these phrasemes, which appear in one or more of ... Five strategies are presented to help learners with their dictionary searches.

  20. 75 FR 30013 - South Feather Water and Power Agency; Notice of Availability of Environmental Assessment

    Science.gov (United States)

    2010-05-28

    ... Water and Power Agency; Notice of Availability of Environmental Assessment May 20, 2010. In accordance... assessment (EA) regarding South Feather Water and Power Agency's (SFWPA) request to raise the dam crest and... Project (FERC No. 2088). Sly Creek is located on Sly Creek [[Page 30014

  1. Directional reflectance and milli-scale feather morphology of the African Emerald Cuckoo, Chrysococcyx cupreus.

    Science.gov (United States)

    Harvey, Todd Alan; Bostwick, Kimberly S; Marschner, Steve

    2013-09-06

    Diverse plumages have evolved among birds through complex morphological modifications. We investigate how the interplay of light with surface and subsurface feather morphology determines the direction of light propagation, an understudied aspect of avian visual signalling. We hypothesize that milli-scale modifications of feathers produce anisotropic reflectance, the direction of which may be predicted by the orientation of the milli-scale structure. The subject of this study is the African Emerald Cuckoo, Chrysococcyx cupreus, noted for its shimmering green iridescent appearance. Using a spherical gantry, we measured the change in the directional reflectance across the feather surface and over a hemisphere of incident lighting directions. Using a microCT scanner, we also studied the morphology of the structural branches of the barb. We tracked the changes in the directional reflectance to the orientation of the structural branches as observed in the CT data. We conclude that (i) the far-field signal of the feather consists of multiple specular components, each associated with a different structural branch and (ii) the direction of each specular component is correlated to the orientation of the corresponding structure.

  2. Hair and feathers as indicator of internal contamination of 210Po and 210Pb

    International Nuclear Information System (INIS)

    Holm, E.; Roos, P.; Henricsson, F.

    2010-03-01

    The activities of the NKS-B HAIRPOL project is summarised in this report. The objective was to investigate if hair and feathers were suitable matrices for the estimation of the intake of 210 Po. Human hair from people of different sex and age was analysed for 210 Po showing concentrations between 0.4 to 11 Bq/kg dry weight. Samples from horses, mane, fur and tail showed concentration from 6 to 17 Bq/kg with no significant difference between the different sample types. Musk ox from Greenland showed much higher concentrations since the animal has to graze a large surface. In fur the concentration was 260 Bq/kg. A considerable fraction of the total 210 Po in this animal is contained in the hair. Also different organs were analysed and the highest concentration was found in kidney, 2 700 Bq/kg. The 210 Pb concentration in hair was estimated to about 20 Bq/kg. Three different seabirds from Svalbard were analysed. Feathers from all three seabird species show increasing activity concentrations of 210 Po and 210 Pb from the base to the tip of the feather, but it was difficult to relate feather concentrations to muscle concentrations due to a number of complicating factors. (author)

  3. Concentration of trace elements in feathers of three Antarctic penguins: Geographical and interspecific differences

    International Nuclear Information System (INIS)

    Jerez, Silvia; Motas, Miguel; Palacios, Maria Jose; Valera, Francisco; Cuervo, Jose Javier; Barbosa, Andres

    2011-01-01

    Antarctica is often considered as one of the last pristine regions, but it could be affected by pollution at global and local scale. Concentrations of Al, Cr, Mn, Fe, Ni, Cu, Zn, As, Se, Cd and Pb were determinated by ICP-MS in feathers (n = 207 individuals) of gentoo, chinstrap and Adelie penguin collected in 8 locations throughout the Antarctic Peninsula (2006-2007). The highest levels of several elements were found in samples from King George Island (8.08, 20.29 and 1.76 μg g -1 dw for Cr, Cu and Pb, respectively) and Deception Island (203.13, 3.26 and 164.26 μg g -1 dw for Al, Mn and Fe, respectively), where probably human activities and large-scale transport of pollutants contribute to increase metal levels. Concentrations of Cr, Mn, Cu, Se or Pb, which are similar to others found in different regions of the world, show that some areas in Antarctica are not utterly pristine. - Highlights: → We study levels of trace elements in feathers of Antarctic penguins. → Eight different rookeries throughout the Antarctic Peninsula were sampled. → Interspecific (gentoo, chinstrap, Adelie) and geographical differences were tested. → Relatively high metal levels were found in areas with major human presence. → Penguin feather can be useful for metals monitoring in the Antarctic environment. - Trace element levels in feathers of three penguin species from the Antarctic Peninsula indicate the presence of pollution in certain locations.

  4. Selection on feather pecking affects response to novelty and foraging behaviour in laying hens

    NARCIS (Netherlands)

    Haas, de E.N.; Nielsen, B.; Rodenburg, T.B.; Buitenhuis, A.J.

    2010-01-01

    Feather pecking (FP) is a major welfare problem in laying hens, influenced by multiple factors. FP is thought to be redirected foraging behaviour, however fearful birds are also known to be more sensitive to develop FP. The relationship between fear-responses, foraging and FP is not well understood,

  5. The prevention and control of feather pecking in laying hens : identifying the underlying principles

    NARCIS (Netherlands)

    Rodenburg, T. B.; van Krimpen, M. M.; de Jong, I. C.; de Haas, E. N.; Kops, M. S.; Riedstra, B. J.; Nordquist, R. E.; Wagenaar, J. P.; Bestman, M.; Nicol, C. J.

    Feather pecking (FP) in laying hens remains an important economic and welfare issue. This paper reviews the literature on causes of FP in laying hens. With the ban on conventional cages in the EU from 2012 and the expected future ban on beak trimming in many European countries, addressing this

  6. Integrating toxicity risk in bird eggs and chicks: using chick down feathers to estimate mercury concentrations in eggs.

    Science.gov (United States)

    Ackerman, Joshua T; Eagles-Smith, Collin A

    2009-03-15

    The concentration of mercury (Hg) in eggs that causes reduced hatching success is regarded as a critical end point for Hg toxicity in birds. However, incorporating effects of in ovo mercury exposure on chick health and survival could improve risk assessment. We developed equations to predict Hg in eggs using Hg in chick down feathers, and vice versa, by assessing the relationship between Hg in feathers (0.5-32.4 microg g(-1) fw) and eggs (0.04-2.79 microg g(-1) fww) for three waterbird species in San Francisco Bay, CA. Feather Hg sampled from embryos of pipping eggs was highly correlated with fresh whole-egg Hg (n=94, r2 = 0.96). Additionally, using an egg microsampling technique, albumen Hg was correlated with feather Hg sampled from chicks in the same nest (n=28, r2 = 0.79). Down feather Hg in recaptured chicks (feather Hg at hatching (feathers of chicks < or =10 days of age to nonlethally predict Hg in eggs and thus provide the ability to develop exposure thresholds for eggs that incorporate in ovo Hg's effects on both egg hatchability and subsequent chick mortality.

  7. Lead accumulation in feathers of nestling black-crowned night-herons (Nycticorax nycticorax) experimentally treated in the field

    Science.gov (United States)

    Golden, N.H.; Rattner, B.A.; Cohen, J.B.; Hoffman, D.J.; Russek-Cohen, E.; Ottinger, M.A.

    2003-01-01

    Although lead can attain high concentrations in feathers, interpretation of the biological significance of this phenomenon is difficult. As part of an effort to develop and validate non-invasive methods to monitor contaminant exposure in free-ranging birds, lead uptake by feathers of nestling black-crowned night-herons (Nycticorax nycticorax) was evaluated in a controlled exposure study. Four to six day-old heron nestlings (one/nest) at Chincoteague Bay, Virginia, received a single intraperitoneal injection of dosing vehicle (control; n=7) or a dose of lead nitrate in water (0.01, 0.05, or 0.25 mg Pb/g body weight of nestling; n=6 or 7/dose) chosen to yield feather lead concentrations found at low to moderately polluted sites. Nestlings were euthanized at 15 days of age. Lead accumulation in feathers was associated with concentrations in bone, kidney, and liver (r = 0.32 - 0.74, p feather lead concentration. Culmen growth rate was depressed in nestlings treated with the highest dose of lead, but not correlated with feather lead concentration. These findings provide evidence that feathers of nestling herons are a sensitive indicator of lead exposure and have potential application for the extrapolation of lead concentrations in other tissues and the estimation of environmental lead exposure in birds.

  8. Lead accumulation in feathers of nestling black-crowned night herons (Nycticorax nycticorax) experimentally treated in the field.

    Science.gov (United States)

    Golden, Nancy H; Rattner, Barnett A; Cohen, Jonathan B; Hoffman, David J; Russek-Cohen, Estelle; Ottinger, Mary Ann

    2003-07-01

    Although lead can attain high concentrations in feathers, interpretation of the biological significance of this phenomenon is difficult. As part of an effort to develop and validate noninvasive methods to monitor contaminant exposure in free-ranging birds, lead uptake by feathers of nestling black-crowned night herons (Nycticorax nycticorax) was evaluated in a controlled exposure study. Four- to 6-d-old heron nestlings (one/nest) at Chincoteague Bay, Virginia (USA), received a single intraperitoneal injection of dosing vehicle (control, n = 7) or a dose of lead nitrate in water (0.01, 0.05, or 0.25 mg Pb/g body wt of nestling; n = 6 or 7/dose) chosen to yield feather lead concentrations found at low- to moderately polluted sites. Nestlings were euthanized at 15 d of age. Lead accumulation in feathers was associated with concentrations in bone, kidney, and liver (r = 0.32-0.74, p feather lead concentration. Culmen growth rate was depressed in nestlings treated with the highest dose of lead but not correlated with feather lead concentration. These findings provide evidence that feathers of nestling herons are a sensitive indicator of lead exposure and have potential application for the extrapolation of lead concentrations in other tissues and the estimation of environmental lead exposure in birds.

  9. Biogas Production from Citrus Wastes and Chicken Feather: Pretreatment and Codigestion

    Energy Technology Data Exchange (ETDEWEB)

    Forgacs, Gergely

    2012-07-01

    Anaerobic digestion is a sustainable and economically feasible waste management technology, which lowers the emission of greenhouse gases (GHGs), decreases the soil and water pollution, and reduces the dependence on fossil fuels. The present thesis investigates the anaerobic digestion of waste from food-processing industries, including citrus wastes (CWs) from juice processing and chicken feather from poultry slaughterhouses. Juice processing industries generate 15-25 million tons of citrus wastes every year. Utilization of CWs is not yet resolved, since drying or incineration processes are costly, due to the high moisture content; and biological processes are hindered by its peel oil content, primarily the D-limonene. Anaerobic digestion of untreated CWs consequently results in process failure because of the inhibiting effect of the produced and accumulated VFAs. The current thesis involves the development of a steam explosion pretreatment step. The methane yield increased by 426 % to 0.537 Nm{sup 3}/kg VS by employing the steam explosion treatment at 150 deg C for 20 min, which opened up the compact structure of the CWs and removed 94 % of the D-limonene. The developed process enables a production of 104 m{sup 3} methane and 8.4 L limonene from one ton of fresh CWs. Poultry slaughterhouses generate a significant amount of feather every year. Feathers are basically composed of keratin, an extremely strong and resistible structural protein. Methane yield from feather is low, around 0.18 Nm{sup 3}/kg VS, which corresponds to only one third of the theoretical yield. In the present study, chemical, enzymatic and biological pretreatment methods were investigated to improve the biogas yield of feather waste. Chemical pretreatment with Ca(OH){sub 2} under relatively mild conditions (0.1 g Ca(OH){sub 2}/g TS{sub feather}, 100 deg C, 30 min) improved the methane yield to 0.40 Nm{sup 3}/kg VS, corresponding to 80 % of the theoretical yield. However, prior to digestion, the

  10. Feather pecking in chickens is genetically related to behavioural and developmental traits.

    Science.gov (United States)

    Jensen, P; Keeling, L; Schütz, K; Andersson, L; Mormède, P; Brändström, H; Forkman, B; Kerje, S; Fredriksson, R; Ohlsson, C; Larsson, S; Mallmin, H; Kindmark, A

    2005-09-15

    Feather pecking (FP) is a detrimental behaviour in chickens, which is performed by only some individuals in a flock. FP was studied in 54 red junglefowl (ancestor of domestic chickens), 36 White Leghorn laying hens, and 762 birds from an F(2)-intercross between these two lines. From all F(2)-birds, growth and feed consumption were measured. Age at sexual maturity and egg production in females, and corticosterone levels in males were also measured. From 333 F(2)-birds of both sexes, and 20 parental birds, body composition with respect to bone mineral content, muscle and fat was obtained by post-mortem examinations using Dual X-Ray Absorptiometry (DXA). In femurs of the same birds, the bone density and structure were analysed using DXA and Peripheral Quantitative Computerized Tomography (pQCT), and a biomechanical analysis of bone strength was performed. Furthermore, plumage condition was determined in all birds as a measure of being exposed to feather pecking. Using 105 DNA-markers in all F(2)-birds, a genome-wide scan for Quantitative Trait Loci (QTL), associated with the behaviour in the F(2)-generation was performed. FP was at least as frequent in the red junglefowl as in the White Leghorn strain studied here, and significantly more common among females both in the parental strains and in the F(2)-generation. In the F(2)-birds, FP was phenotypically linked to early sexual maturation, fast growth, weak bones, and, in males, also high fat accumulation, indicating that feather peckers have a different resource allocation pattern. Behaviourally, F(2) feather peckers were more active in an open field test, in a novel food/novel object test, and in a restraint test, indicating that feather pecking might be genetically linked to a proactive coping strategy. Only one suggestive QTL with a low explanatory value was found on chromosome 3, showing that many genes, each with a small effect, are probably involved in the causation of feather pecking. There were significant

  11. Haste makes waste but condition matters: molt rate-feather quality trade-off in a sedentary songbird.

    Directory of Open Access Journals (Sweden)

    Csongor I Vágási

    Full Text Available The trade-off between current and residual reproductive values is central to life history theory, although the possible mechanisms underlying this trade-off are largely unknown. The 'molt constraint' hypothesis suggests that molt and plumage functionality are compromised by the preceding breeding event, yet this candidate mechanism remains insufficiently explored.The seasonal change in photoperiod was manipulated to accelerate the molt rate. This treatment simulates the case of naturally late-breeding birds. House sparrows Passer domesticus experiencing accelerated molt developed shorter flight feathers with more fault bars and body feathers with supposedly lower insulation capacity (i.e. shorter, smaller, with a higher barbule density and fewer plumulaceous barbs. However, the wing, tail and primary feather lengths were shorter in fast-molting birds if they had an inferior body condition, which has been largely overlooked in previous studies. The rachis width of flight feathers was not affected by the treatment, but it was still condition-dependent.This study shows that sedentary birds might face evolutionary costs because of the molt rate-feather quality conflict. This is the first study to experimentally demonstrate that (1 molt rate affects several aspects of body feathers as well as flight feathers and (2 the costly effects of rapid molt are condition-specific. We conclude that molt rate and its association with feather quality might be a major mediator of life history trade-offs. Our findings also suggest a novel advantage of early breeding, i.e. the facilitation of slower molt and the condition-dependent regulation of feather growth.

  12. Haste Makes Waste but Condition Matters: Molt Rate–Feather Quality Trade-Off in a Sedentary Songbird

    Science.gov (United States)

    Vágási, Csongor I.; Pap, Péter L.; Vincze, Orsolya; Benkő, Zoltán; Marton, Attila; Barta, Zoltán

    2012-01-01

    Background The trade-off between current and residual reproductive values is central to life history theory, although the possible mechanisms underlying this trade-off are largely unknown. The ‘molt constraint’ hypothesis suggests that molt and plumage functionality are compromised by the preceding breeding event, yet this candidate mechanism remains insufficiently explored. Methodology/Principal Findings The seasonal change in photoperiod was manipulated to accelerate the molt rate. This treatment simulates the case of naturally late-breeding birds. House sparrows Passer domesticus experiencing accelerated molt developed shorter flight feathers with more fault bars and body feathers with supposedly lower insulation capacity (i.e. shorter, smaller, with a higher barbule density and fewer plumulaceous barbs). However, the wing, tail and primary feather lengths were shorter in fast-molting birds if they had an inferior body condition, which has been largely overlooked in previous studies. The rachis width of flight feathers was not affected by the treatment, but it was still condition-dependent. Conclusions/Significance This study shows that sedentary birds might face evolutionary costs because of the molt rate–feather quality conflict. This is the first study to experimentally demonstrate that (1) molt rate affects several aspects of body feathers as well as flight feathers and (2) the costly effects of rapid molt are condition-specific. We conclude that molt rate and its association with feather quality might be a major mediator of life history trade-offs. Our findings also suggest a novel advantage of early breeding, i.e. the facilitation of slower molt and the condition-dependent regulation of feather growth. PMID:22808221

  13. Development of colour-producing β-keratin nanostructures in avian feather barbs

    Science.gov (United States)

    Prum, Richard O.; Dufresne, Eric R.; Quinn, Tim; Waters, Karla

    2009-01-01

    The non-iridescent structural colours of avian feather barbs are produced by coherent light scattering from amorphous (i.e. quasi-ordered) nanostructures of β-keratin and air in the medullary cells of feather barb rami. Known barb nanostructures belong to two distinct morphological classes. ‘Channel’ nanostructures consist of β-keratin bars and air channels of elongate, tortuous and twisting forms. ‘Spherical’ nanostructures consist of highly spherical air cavities that are surrounded by thin β-keratin bars and sometimes interconnected by tiny passages. Using transmission electron microscopy, we observe that the colour-producing channel-type nanostructures of medullary β-keratin in feathers of the blue-and-yellow macaw (Ara ararauna, Psittacidae) develop by intracellular self-assembly; the process proceeds in the absence of any biological prepattern created by the cell membrane, endoplasmic reticulum or cellular intermediate filaments. We examine the hypothesis that the shape and size of these self-assembled, intracellular nanostructures are determined by phase separation of β-keratin protein from the cytoplasm of the cell. The shapes of a broad sample of colour-producing channel-type nanostructures from nine avian species are very similar to those self-assembled during the phase separation of an unstable mixture, a process called spinodal decomposition (SD). In contrast, the shapes of a sample of spherical-type nanostructures from feather barbs of six species show a poor match to SD. However, spherical nanostructures show a strong morphological similarity to morphologies produced by phase separation of a metastable mixture, called nucleation and growth. We propose that colour-producing, intracellular, spongy medullary β-keratin nanostructures develop their characteristic sizes and shapes by phase separation during protein polymerization. We discuss the possible role of capillary flow through drying of medullary cells in the development of the hollow

  14. Development of colour-producing beta-keratin nanostructures in avian feather barbs.

    Science.gov (United States)

    Prum, Richard O; Dufresne, Eric R; Quinn, Tim; Waters, Karla

    2009-04-06

    The non-iridescent structural colours of avian feather barbs are produced by coherent light scattering from amorphous (i.e. quasi-ordered) nanostructures of beta-keratin and air in the medullary cells of feather barb rami. Known barb nanostructures belong to two distinct morphological classes. 'Channel' nanostructures consist of beta-keratin bars and air channels of elongate, tortuous and twisting forms. 'Spherical' nanostructures consist of highly spherical air cavities that are surrounded by thin beta-keratin bars and sometimes interconnected by tiny passages. Using transmission electron microscopy, we observe that the colour-producing channel-type nanostructures of medullary beta-keratin in feathers of the blue-and-yellow macaw (Ara ararauna, Psittacidae) develop by intracellular self-assembly; the process proceeds in the absence of any biological prepattern created by the cell membrane, endoplasmic reticulum or cellular intermediate filaments. We examine the hypothesis that the shape and size of these self-assembled, intracellular nanostructures are determined by phase separation of beta-keratin protein from the cytoplasm of the cell. The shapes of a broad sample of colour-producing channel-type nanostructures from nine avian species are very similar to those self-assembled during the phase separation of an unstable mixture, a process called spinodal decomposition (SD). In contrast, the shapes of a sample of spherical-type nanostructures from feather barbs of six species show a poor match to SD. However, spherical nanostructures show a strong morphological similarity to morphologies produced by phase separation of a metastable mixture, called nucleation and growth. We propose that colour-producing, intracellular, spongy medullary beta-keratin nanostructures develop their characteristic sizes and shapes by phase separation during protein polymerization. We discuss the possible role of capillary flow through drying of medullary cells in the development of the

  15. Variance components and selection response for feather-pecking behavior in laying hens.

    Science.gov (United States)

    Su, G; Kjaer, J B; Sørensen, P

    2005-01-01

    Variance components and selection response for feather pecking behavior were studied by analyzing the data from a divergent selection experiment. An investigation indicated that a Box-Cox transformation with power lambda = -0.2 made the data approximately normally distributed and gave the best fit for the model. Variance components and selection response were estimated using Bayesian analysis with Gibbs sampling technique. The total variation was rather large for the investigated traits in both the low feather-pecking line (LP) and the high feather-pecking line (HP). Based on the mean of marginal posterior distribution, in the Box-Cox transformed scale, heritability for number of feather pecking bouts (FP bouts) was 0.174 in line LP and 0.139 in line HP. For number of feather-pecking pecks (FP pecks), heritability was 0.139 in line LP and 0.105 in line HP. No full-sib group effect and observation pen effect were found in the 2 traits. After 4 generations of selection, the total response for number of FP bouts in the transformed scale was 58 and 74% of the mean of the first generation in line LP and line HP, respectively. The total response for number of FP pecks was 47 and 46% of the mean of the first generation in line LP and line HP, respectively. The variance components and the realized selection response together suggest that genetic selection can be effective in minimizing FP behavior. This would be expected to reduce one of the major welfare problems in laying hens.

  16. Module-based complexity formation: periodic patterning in feathers and hairs.

    Science.gov (United States)

    Chuong, Cheng-Ming; Yeh, Chao-Yuan; Jiang, Ting-Xin; Widelitz, Randall

    2013-01-01

    Patterns describe order which emerges from homogeneity. Complex patterns on the integument are striking because of their visibility throughout an organism’s lifespan. Periodic patterning is an effective design because the ensemble of hair or feather follicles (modules) allows the generation of complexity, including regional variations and cyclic regeneration, giving the skin appendages a new lease on life. Spatial patterns include the arrangements of feathers and hairs in specific number, size, and spacing.We explorehowa field of equivalent progenitor cells can generate periodically arranged modules based on genetic information, physical–chemical rules and developmental timing. Reconstitution experiments suggest a competitive equilibrium regulated by activators/inhibitors involving Turing reaction-diffusion. Temporal patterns result from oscillating stem cell activities within each module (microenvironment regulation), reflected as growth (anagen) and resting (telogen) phases during the cycling of feather and hair follicles. Stimulating modules with activators initiates the spread of regenerative hair waves, while global inhibitors outside each module (macroenvironment) prevent this. Different wave patterns can be simulated by cellular automata principles. Hormonal status and seasonal changes can modulate appendage phenotypes, leading to ‘organ metamorphosis’, with multiple ectodermal organ phenotypes generated from the same precursors. We discuss potential novel evolutionary steps using this module-based complexity in several amniote integument organs, exemplified by the spectacular peacock feather pattern. We thus explore the application of the acquired knowledge of patterning in tissue engineering. New hair follicles can be generated after wounding. Hairs and feathers can be reconstituted through self-organization of dissociated progenitor cells. © 2012 Wiley Periodicals, Inc.

  17. Vaccination elicits a prominent acute phase response in horses.

    Science.gov (United States)

    Andersen, Susanne A; Petersen, Henrik H; Ersbøll, Annette K; Falk-Rønne, Jørgen; Jacobsen, Stine

    2012-02-01

    European and American guidelines for vaccination against tetanus and influenza in horses recommend annual and annual/semi-annual vaccinations, respectively, against the two pathogens. Too-frequent vaccination may, however, have adverse effects, among other things because an inflammatory response is elicited with subsequent alterations in homeostasis. The objective of the study was to compare the acute phase response (APR) in 10 horses following administration of two different types of vaccines, namely, an inactivated Immune Stimulating COMplex (ISCOM) vaccine and a live recombinant vector vaccine. Blood was sampled before and after vaccination to measure levels of serum amyloid A (SAA), fibrinogen, white blood cell counts (WBC) and iron. Vaccination induced a prominent APR with increased WBC, elevated blood levels of SAA and fibrinogen, and decreased serum iron concentrations. The ISCOM vaccine caused significantly (Phorse owners about convalescence after vaccination. Copyright © 2011 Elsevier Ltd. All rights reserved.

  18. Clinical Mass Spectrometry: Achieving Prominence in Laboratory Medicine

    Energy Technology Data Exchange (ETDEWEB)

    Annesley, Thomas M.; Cooks, Robert G.; Herold, David A.; Hoofnagle, Andrew N.

    2016-01-04

    Each year the journal Clinical Chemistry publishes a January special issue on a topic that is relevant to the laboratory medicine community. In January 2016 the topic is mass spectrometry, and the issue is entitled “Clinical Mass Spectrometry: Achieving Prominence in Laboratory Medicine”. One popular feature in our issues is a Q&A on a topic, clearly in this case mass spectrometry. The journal is assembling a panel of 5-6 experts from various areas of mass spectrometry ranging from instrument manufacturing to practicing clinical chemists. Dick Smith is one of the scientist requested to participate in this special issue Q&A on Mass Spectrometry. The Q&A Transcript is attached

  19. Old World frog and bird vocalizations contain prominent ultrasonic harmonics

    Science.gov (United States)

    Narins, Peter M.; Feng, Albert S.; Lin, Wenyu; Schnitzler, Hans-Ulrich; Denzinger, Annette; Suthers, Roderick A.; Xu, Chunhe

    2004-02-01

    Several groups of mammals such as bats, dolphins and whales are known to produce ultrasonic signals which are used for navigation and hunting by means of echolocation, as well as for communication. In contrast, frogs and birds produce sounds during night- and day-time hours that are audible to humans; their sounds are so pervasive that together with those of insects, they are considered the primary sounds of nature. Here we show that an Old World frog (Amolops tormotus) and an oscine songbird (Abroscopus albogularis) living near noisy streams reliably produce acoustic signals that contain prominent ultrasonic harmonics. Our findings provide the first evidence that anurans and passerines are capable of generating tonal ultrasonic call components and should stimulate the quest for additional ultrasonic species.

  20. Decomposition of intact chicken feathers by a thermophile in combination with an acidulocomposting garbage-treatment process.

    Science.gov (United States)

    Shigeri, Yasushi; Matsui, Tatsunobu; Watanabe, Kunihiko

    2009-11-01

    In order to develop a practical method for the decomposition of intact chicken feathers, a moderate thermophile strain, Meiothermus ruber H328, having strong keratinolytic activity, was used in a bio-type garbage-treatment machine working with an acidulocomposting process. The addition of strain H328 cells (15 g) combined with acidulocomposting in the garbage machine resulted in 70% degradation of intact chicken feathers (30 g) within 14 d. This degradation efficiency is comparable to a previous result employing the strain as a single bacterium in flask culture, and it indicates that strain H328 can promote intact feather degradation activity in a garbage machine currently on the market.

  1. Three-Dimensional Morphology of a Coronal Prominence Cavity

    Science.gov (United States)

    Gibson, S. E.; Kucera, T. A.; Rastawicki, D.; Dove, J.; deToma, G.; Hao, J.; Hill, S.; Hudson, H. S.; Marque, C.; McIntosh, P. S.; hide

    2010-01-01

    We present a three-dimensional density model of coronal prominence cavities, and a morphological fit that has been tightly constrained by a uniquely well-observed cavity. Observations were obtained as part of an International Heliophysical Year campaign by instruments from a variety of space- and ground-based observatories, spanning wavelengths from radio to soft-X-ray to integrated white light. From these data it is clear that the prominence cavity is the limb manifestation of a longitudinally-extended polar-crown filament channel, and that the cavity is a region of low density relative to the surrounding corona. As a first step towards quantifying density and temperature from campaign spectroscopic data, we establish the three-dimensional morphology of the cavity. This is critical for taking line-of-sight projection effects into account, since cavities are not localized in the plane of the sky and the corona is optically thin. We have augmented a global coronal streamer model to include a tunnel-like cavity with elliptical cross-section and a Gaussian variation of height along the tunnel length. We have developed a semi-automated routine that fits ellipses to cross-sections of the cavity as it rotates past the solar limb, and have applied it to Extreme Ultraviolet Imager (EUVI) observations from the two Solar Terrestrial Relations Observatory (STEREO) spacecraft. This defines the morphological parameters of our model, from which we reproduce forward-modeled cavity observables. We find that cavity morphology and orientation, in combination with the viewpoints of the observing spacecraft, explains the observed variation in cavity visibility for the east vs. west limbs

  2. Clinico-Epidemiological Comparison of Delusion-Prominent and Hallucination-Prominent Clinical Subgroups of Paranoid Schizophrenia.

    Science.gov (United States)

    Kreinin, Anatoly; Krishtul, Vladimir; Kirsh, Zvi; Menuchin, Michael

    2015-01-01

    Though hallucinations and delusions are prominent basic impairments in schizophrenia, reports of the relationship between hallucinatory and delusional symptoms among schizophrenia patients are scant. To examine the epidemiological and clinical differences between mainly hallucinatory and mainly delusional subgroups of paranoid schizophrenia patients. One hundred schizophrenia patients, paranoid type, were recruited. In a cross-sectional study, participants were divided into Mainly Hallucinatory (H) and Mainly Delusional (D) subgroups. Demographic variables were compared and clinical characteristics were evaluated using the Scale for the Assessment of Positive Symptoms, the Scale for the Assessment of Negative Symptoms, and the Clinical Global Impression Scale. The Quality-of-Life Enjoyment and Satisfaction Questionnaire-18 was used to assess quality of life. Clinically, the H group was more heterogeneous as expressed by the broader range of scores that described the clinical picture of patients in that subgroup (in 43 of 78 variables, 55.13%) and similar ranges of scores (31 of 78 variables, 39.74%) for patients in the D group. Duration of hospitalization was significantly longer in group H than in group D (p=0.047). There was no statistically significant difference between the H and D subgroups in demographic characteristics. There are distinct epidemiological and clinical differences between the H and D subgroups, with more severe positive and negative symptoms and greater functional impairment in the H group. Paranoid schizophrenia patients with prominent hallucinations have poorer prognosis and need intensive therapeutic rehabilitation beginning with onset-of-illness. Further genetic studies and comparisons of fMRI and/or PET findings are warranted to investigate additional distinctive characteristics of these subgroups.

  3. Formulation of economical microbial feed using degraded chicken feathers by a novel Streptomyces sp: mitigation of environmental pollution

    Directory of Open Access Journals (Sweden)

    Jayapradha Ramakrishnan

    2011-09-01

    Full Text Available A new Streptomyces sp. IF 5 was isolated from the feather dumped soil and found to have a tremendous keratinase activity. The strain enabled the degradation of the chicken feathers very effectively in 60 h. The 16S rRNA sequence of 1474 bp long was submitted to the National centre for Biotechnological information. The keratinolytic activity in the culture medium was 1181 U/ml. The release and analyses of sulphydryl groups in the culture medium evident the degradation activity by the Streptomyces sp. IF 5. The idea of the present study was to use the degraded chicken feathers as the substrate for the growth and cultivation of microorganisms. We have designed a very economical culture medium that includes the usage of some basal salts alone and degraded chicken feathers (10 g/l. The results of the specific growth rate of the tested microbes confirm the usage of the new designed medium for microbial culturing.

  4. In vitro gas production tests on irradiated-chicken feathers to estimate its nutritive value as feed for ruminants

    International Nuclear Information System (INIS)

    Deocaris, Custer C.; De Vera, Azucena C.; Asaad, Celia O.; Ellana, Marivic M.

    2003-01-01

    Chicken feathers are a highly abundant agro-waste product containing high amount of protein from keratin. However, these are not practically utilized as animal feeds since they provide little, if any nutritional value due to low digestibility in its natural state. Using an in vitro fermentation approach, the ruminant feed potential of chicken feathers treated with gamma-radiation was estimated. Gas production within an incubation period of 96 hours was monitored and values were fitted in the rumen degradability model by McDonald and Orskov (1981). Radiation treatment which could induce depolymerization of chicken feather keratin allowed for the improvement in the nutritive value for ruminants by liberating an additional 7.2% in metabolizable energy (ME) (P<0.005) for ruminant livestock. However, increasing the absorbed dose to 50 kGy resulted in significantly lower energy value for the feather substrate possibility accrued from the induced protein-protein cross-linking phenomenon. (Authors)

  5. Optimisation of surfactant decontamination and pre-treatment of waste chicken feathers by using response surface methodology

    CSIR Research Space (South Africa)

    Tesfaye, T

    2018-02-01

    Full Text Available Commercially processed, untreated chicken feathers are biologically hazardous due to the presence of blood-borne pathogens. Prior to valorisation, it is crucial that they are decontaminated to remove the microbial contamination. The present study...

  6. Morphometric characterisation of wing feathers of the barn owl Tyto alba pratincola and the pigeon Columba livia

    Directory of Open Access Journals (Sweden)

    Klaas Michael

    2007-11-01

    Full Text Available Abstract Background Owls are known for their silent flight. Even though there is some information available on the mechanisms that lead to a reduction of noise emission, neither the morphological basis, nor the biological mechanisms of the owl's silent flight are known. Therefore, we have initiated a systematic analysis of wing morphology in both a specialist, the barn owl, and a generalist, the pigeon. This report presents a comparison between the feathers of the barn owl and the pigeon and emphasise the specific characteristics of the owl's feathers on macroscopic and microscopic level. An understanding of the features and mechanisms underlying this silent flight might eventually be employed for aerodynamic purposes and lead to a new wing design in modern aircrafts. Results A variety of different feathers (six remiges and six coverts, taken from several specimen in either species, were investigated. Quantitative analysis of digital images and scanning electron microscopy were used for a morphometric characterisation. Although both species have comparable body weights, barn owl feathers were in general larger than pigeon feathers. For both species, the depth and the area of the outer vanes of the remiges were typically smaller than those of the inner vanes. This difference was more pronounced in the barn owl than in the pigeon. Owl feathers also had lesser radiates, longer pennula, and were more translucent than pigeon feathers. The two species achieved smooth edges and regular surfaces of the vanes by different construction principles: while the angles of attachment to the rachis and the length of the barbs was nearly constant for the barn owl, these parameters varied in the pigeon. We also present a quantitative description of several characteristic features of barn owl feathers, e.g., the serrations at the leading edge of the wing, the fringes at the edges of each feather, and the velvet-like dorsal surface. Conclusion The quantitative

  7. Radiologic comparison of erosive polyarthritis with prominent interphalangeal involvement

    International Nuclear Information System (INIS)

    Gold, R.H.; Bassett, L.W.; Theros, E.G.

    1982-01-01

    Psoriatic arthritis, Reiter's disease, and multicentric reticulohistiocytosis may manifest prominent interphalangeal joint and cutaneous involvement. All three disorders may also affect the sacroiliac joints and spine. Despite these similarities, there are basic radiologic differences enabling distinction between the three disorders. Erosive osteoarthritis must also be considered in the differential diagnosis of interphalangeal erosive arthritis. Psoriatic erosions are characteristically ill defined, often bilaterally asymmetrical, usually unaccompanied by significant osteoporosis, and frequently associated with florid proliferation of subperiosteal new bone. An unilateral polyarticular pattern, which often occurs in a single ray, is the most prevalent of several patterns of involvement. Reiter's disease exhibits many clinical and radiologic similarities to psoriatic arthritis, but in the former there tends to be selective involvement of the joints of the lower limbs and particularly the feet, with relative sparing of the hands and wrists, while in the latter the joints of the upper and lower limbs tend to be involved to an equal extent. Multicentric reticulohistiocytosis (MR). Lesions predominate in skin and synovium and result in sharply circumscribed, rapidly progressive, strikingly bilaterally symmetrical erosions spreading from joint margins to articular surfaces. Most or all of the diarthrodial joints may be affected, but interphalangeal joint predominance and early and severe atlanto-axial involvement are characteristic. Erosive osteoarthritis is characterized by interphalangeal subchondral erosions, accompanying periosteal new bone that is more subtle than that of psoriatic arthritis, and interphalangeal bony ankylosis that occurs with the same frequency as that of psoriatic arthritis. (orig.)

  8. Quantifying the cepstral peak prominence, a measure of dysphonia.

    Science.gov (United States)

    Heman-Ackah, Yolanda D; Sataloff, Robert T; Laureyns, Griet; Lurie, Deborah; Michael, Deirdre D; Heuer, Reinhardt; Rubin, Adam; Eller, Robert; Chandran, Swapna; Abaza, Mona; Lyons, Karen; Divi, Venu; Lott, Joanna; Johnson, Jennifer; Hillenbrand, James

    2014-11-01

    The purpose of this study is to establish normative values for the smoothed cepstral peak prominence (CPPS) and its sensitivity and specificity as a measure of dysphonia. Prospective cohort study. Voice samples of running speech were obtained from 835 patients and 50 volunteers. Eight laryngologists and four speech-language pathologists performed perceptual ratings of the voice samples on the degree of dysphonia/normality using an analog scale. The mean of their perceptual ratings was used as the gold standard for the detection of the presence or absence of dysphonia. CPPS was measured using the CPPS algorithm of Hillenbrand, and the cut-off value for positivity that has the highest sensitivity and specificity for discriminating between normal and severely dysphonia voices was determined based on ROC-curve analysis. The cut-off value for normal for CPPS was set at 4.0 or higher, which gave a sensitivity of 92.4%, a specificity of 79%, a positive predictive value of 82.5%, and a negative predictive value of 90.8%. The area under the receiver operating characteristic (ROC) curve was 0.937 (P dysphonia, with the normal value of CPPS (Hillenbrand algorithm) of a running speech sample being defined as a value of 4.0 or higher. Copyright © 2014 The Voice Foundation. All rights reserved.

  9. Porcine CD38 exhibits prominent secondary NAD(+) cyclase activity.

    Science.gov (United States)

    Ting, Kai Yiu; Leung, Christina F P; Graeff, Richard M; Lee, Hon Cheung; Hao, Quan; Kotaka, Masayo

    2016-03-01

    Cyclic ADP-ribose (cADPR) mobilizes intracellular Ca(2+) stores and activates Ca(2+) influx to regulate a wide range of physiological processes. It is one of the products produced from the catalysis of NAD(+) by the multifunctional CD38/ADP-ribosyl cyclase superfamily. After elimination of the nicotinamide ring by the enzyme, the reaction intermediate of NAD(+) can either be hydrolyzed to form linear ADPR or cyclized to form cADPR. We have previously shown that human CD38 exhibits a higher preference towards the hydrolysis of NAD(+) to form linear ADPR while Aplysia ADP-ribosyl cyclase prefers cyclizing NAD(+) to form cADPR. In this study, we characterized the enzymatic properties of porcine CD38 and revealed that it has a prominent secondary NAD(+) cyclase activity producing cADPR. We also determined the X-ray crystallographic structures of porcine CD38 and were able to observe conformational flexibility at the base of the active site of the enzyme which allow the NAD(+) reaction intermediate to adopt conformations resulting in both hydrolysis and cyclization forming linear ADPR and cADPR respectively. © 2016 The Protein Society.

  10. Prominent feature extraction for review analysis: an empirical study

    Science.gov (United States)

    Agarwal, Basant; Mittal, Namita

    2016-05-01

    Sentiment analysis (SA) research has increased tremendously in recent times. SA aims to determine the sentiment orientation of a given text into positive or negative polarity. Motivation for SA research is the need for the industry to know the opinion of the users about their product from online portals, blogs, discussion boards and reviews and so on. Efficient features need to be extracted for machine-learning algorithm for better sentiment classification. In this paper, initially various features are extracted such as unigrams, bi-grams and dependency features from the text. In addition, new bi-tagged features are also extracted that conform to predefined part-of-speech patterns. Furthermore, various composite features are created using these features. Information gain (IG) and minimum redundancy maximum relevancy (mRMR) feature selection methods are used to eliminate the noisy and irrelevant features from the feature vector. Finally, machine-learning algorithms are used for classifying the review document into positive or negative class. Effects of different categories of features are investigated on four standard data-sets, namely, movie review and product (book, DVD and electronics) review data-sets. Experimental results show that composite features created from prominent features of unigram and bi-tagged features perform better than other features for sentiment classification. mRMR is a better feature selection method as compared with IG for sentiment classification. Boolean Multinomial Naïve Bayes) algorithm performs better than support vector machine classifier for SA in terms of accuracy and execution time.

  11. Combined surgical management of mandibular angle prominence and microgenia

    International Nuclear Information System (INIS)

    Portelles Masso, Ayelen Maria; Berger Kohn, Carlos

    2010-01-01

    Chin play a very important role in facial aesthetics. Different deformities of volume and of position may occur at this level and it is the microgenia one of the more frequent. Treatment options include the use of silicone, alloplasty materials and autologous bone graft. Authors report the use of the bone removed from mandibular angle to increase the chin. This is the case of a white female patient aged 18 seen by the Orthognathics Multidisciplinary Staff of 'V. I. Lenin' Hospital due to its uncommon face width. The corresponding physical examination as well as the complementary ones diagnosed a bilateral prominence of mandibular angle associated with a microgenia. Surgery carried out was of remodeling type of both mandibular angles and genioplasty of height increase and a discrete advancement using the bone removed from the gonion. There were satisfactory aesthetic results without evidence of bone reabsorption. We conclude that use of autologous graft of mandibular angle is an effective treatment alternative for correction of microgenia. (author)

  12. The coordination of boundary tones and its interaction with prominence.

    Science.gov (United States)

    Katsika, Argyro; Krivokapić, Jelena; Mooshammer, Christine; Tiede, Mark; Goldstein, Louis

    2014-05-01

    This study investigates the coordination of boundary tones as a function of stress and pitch accent. Boundary tone coordination has not been experimentally investigated previously, and the effect of prominence on this coordination, and whether it is lexical (stress-driven) or phrasal (pitch accent-driven) in nature is unclear. We assess these issues using a variety of syntactic constructions to elicit different boundary tones in an Electromagnetic Articulography (EMA) study of Greek. The results indicate that the onset of boundary tones co-occurs with the articulatory target of the final vowel. This timing is further modified by stress, but not by pitch accent: boundary tones are initiated earlier in words with non-final stress than in words with final stress regardless of accentual status. Visual data inspection reveals that phrase-final words are followed by acoustic pauses during which specific articulatory postures occur. Additional analyses show that these postures reach their achievement point at a stable temporal distance from boundary tone onsets regardless of stress position. Based on these results and parallel findings on boundary lengthening reported elsewhere, a novel approach to prosody is proposed within the context of Articulatory Phonology: rather than seeing prosodic (lexical and phrasal) events as independent entities, a set of coordination relations between them is suggested. The implications of this account for prosodic architecture are discussed.

  13. Prominent Determinants of Consumer-Based Brand Equity

    Directory of Open Access Journals (Sweden)

    Elisa Battistoni

    2013-08-01

    Full Text Available In this paper we investigate the most prominent drivers of brand equity, from a consumerbased point of view. We present a new approach for measuring brand equity, which can be applied regardless of the brand sector and is based on the Analytic Hierarchy Process. This approach has the main advantage of allowing for comparisons to be made between non‐directly measurable elements and also has the advantage of enabling the ranking of intangible criteria, such as consumers’ feelings or purchase intentions. We focus on the fashion industry, since we believe in the higher value of our approach when applied to brands which offer products with less tangible characteristics. Thanks to a case study – which involved about 250 interviewees – we succeed in finding and prioritizing the elements which can have an impact on the brand value. We also provide a global ranking for three apparel brands: Gap, H&M and Zara. The results from our model are consistent with other popular ratings and can be extremely useful for brand managers.

  14. Harmonic hopping, and both punctuated and gradual evolution of acoustic characters in Selasphorus hummingbird tail-feathers.

    Directory of Open Access Journals (Sweden)

    Christopher James Clark

    Full Text Available Models of character evolution often assume a single mode of evolutionary change, such as continuous, or discrete. Here I provide an example in which a character exhibits both types of change. Hummingbirds in the genus Selasphorus produce sound with fluttering tail-feathers during courtship. The ancestral character state within Selasphorus is production of sound with an inner tail-feather, R2, in which the sound usually evolves gradually. Calliope and Allen's Hummingbirds have evolved autapomorphic acoustic mechanisms that involve feather-feather interactions. I develop a source-filter model of these interactions. The 'source' comprises feather(s that are both necessary and sufficient for sound production, and are aerodynamically coupled to neighboring feathers, which act as filters. Filters are unnecessary or insufficient for sound production, but may evolve to become sources. Allen's Hummingbird has evolved to produce sound with two sources, one with feather R3, another frequency-modulated sound with R4, and their interaction frequencies. Allen's R2 retains the ancestral character state, a ∼1 kHz "ghost" fundamental frequency masked by R3, which is revealed when R3 is experimentally removed. In the ancestor to Allen's Hummingbird, the dominant frequency has 'hopped' to the second harmonic without passing through intermediate frequencies. This demonstrates that although the fundamental frequency of a communication sound may usually evolve gradually, occasional jumps from one character state to another can occur in a discrete fashion. Accordingly, mapping acoustic characters on a phylogeny may produce misleading results if the physical mechanism of production is not known.

  15. Low chronic doses impact on activity and component composition of oxidizing enzymes and dehydrogenates and feather-crass DNA structure

    International Nuclear Information System (INIS)

    Sarsenbaev, K.N.; Sarsembeva, M.; Ajdosova, S.S.; Zaka, R.; Misset, M.

    2005-01-01

    The paper is dedicated to study of nuclear explosion effects to morphological, biochemical and genetic properties of dominant plant of the STS - feather-grass. The cited data are evidence of birth of new genotypes having effective enzymatic anti-oxidative system and genes that coordinated them. It is result of the feather-grass growing during 40 years under conditions of chronic radiation. (author)

  16. Wedge cells during regeneration of juvenile and adult feathers and their role in carving out the branching pattern of barbs.

    Science.gov (United States)

    Alibardi, Lorenzo

    2007-01-01

    The present ultrastructural study on regenerating feathers emphasizes the role of supportive cells in determining the branching pattern of barbs. Supportive cells are localized among developing barb and barbule cells, in marginal plates, and underneath the feather sheath, and their differentiative fate, in general, is a form of lipid degeneration. The Latter process determines the carving out of barb branching in both downfeathers and pennaceous feathers. In the latter feathers, some supportive cells (barb vane cells and cylindrical cells of marginal plates) degenerate within each barb ridge leaving separate barbules. Other supportive cells, here termed wedge cells, form columns of cornified material that merge into elongated corneous scaffolds localized among barbs and the rachis. This previously undescribed form of cornification of supportive cells derives from the aggregation of periderm and dense granules present in wedge cells. The latter cells give origin to a corneous material different from feather keratin that may initially sustain the early and soft barbules. After barbules are cornified the supportive cells scaffolds are eventually sloughed as the sheath breaks allowing the new feather to open up and form a planar vane. The corneous material of wedge cells may also contribute to molding of the overlapped nodes of barbule cells that form lateral spines or hooklets in mature barbules. Eventually, the disappearance of wedge cell scaffolding determines the regular spacing of barbs attached to the rachis in order to form a close vane.

  17. Proteomic analysis of enzyme production by Bacillus licheniformis using different feather wastes as the sole fermentation media.

    Science.gov (United States)

    Parrado, J; Rodriguez-Morgado, B; Tejada, M; Hernandez, T; Garcia, C

    2014-04-10

    This study evaluates the use of different types of feathers as fermentation media for enzyme production. Bacillus licheniformis was grown on the feathers, which lead to total biodegradation due to bacterial enzymatic hydrolytic excretion. B. licheniformis excretes protease and lipase activity, with feather concentration being the main parameter controlling their generation. Using a proteomic approach, the proteins excreted during fermentation were identified, and the influence of the chemical composition of the feathers on protein secretion was tested. The identified proteins are hydrolytic enzymes such as keratinase, gamma-glutamyltranspeptidase, chitosanases, and glicosidases. The diversity of proteins is related to the chemical complexity of the feathers. Understanding the composition of a hydrolytic system, when B. licheniformis is cultured on different feathers, may assist in utilizing such a system for producing different hydrolytic enzymes. The data indicate that proteomics can be a valuable tool for describing the physiological state of B. licheniformis cell populations growing on different wastes. Copyright © 2014 Elsevier Inc. All rights reserved.

  18. Piecewise mass flows within a solar prominence observed by the New Vacuum Solar Telescope

    Science.gov (United States)

    Li, Hongbo; Liu, Yu; Tam, Kuan Vai; Zhao, Mingyu; Zhang, Xuefei

    2018-06-01

    The material of solar prominences is often observed in a state of flowing. These mass flows (MF) are important and useful for us to understand the internal structure and dynamics of prominences. In this paper, we present a high resolution Hα observation of MFs within a quiescent solar prominence. From the observation, we find that the plasma primarily has a circular motion and a downward motion separately in the middle section and legs of the prominence, which creates a piecewise mass flow along the observed prominence. Moreover, the observation also shows a clear displacement of MF's velocity peaks in the middle section of the prominence. All of these provide us with a detailed record of MFs within a solar prominence and show a new approach to detecting the physical properties of prominence.

  19. Prominent central spinal canal on MRI - normal variant or pathology

    International Nuclear Information System (INIS)

    Dugal, T.P.; Brazier, D.; Roche, J.

    2002-01-01

    Full text: The sensitivity of MRI can make differentiation of normal from abnormal challenging.The study investigates whether a visible central spinal canal is pathological or a normal variant. We review eight MRI (mostly on a 1.5 Tesla unit) cases where there is a visible central cavity in keeping with a central canal and review the literature. The central canal is a space in the medial part of the grey-matter commissure between the anterior and posterior horns. Histopathological studies show that the canal is present at birth with the majority showing subsequent involution but is uncommonly imaged on MRI. The main differential diagnosis is syringomyelia which usually presents with deficits in pain and sensation corresponding to the appropriate level often with a demonstrable aetiology. Two thirds of our patients were female with an average age of thirty-six years (range 26-45). The patients were largely asymptomatic or their symptoms appeared unrelated to the imaging findings. Three patients had minor previous trauma and two others had non-bacterial meningitis up to twenty years earlier. No patient had known spinal surgery or trauma.The cavity corresponded tomographically to the expected site of the central canal. The canal was in the thoracic location. The canal diameter ranged from one to five millimetres and its length varied from one half a vertebral body height to extending over the entire thoracic region. Its configuration was either filiform or fusiform, with smooth contours. No predisposing features to suggest syringomyelia or other structural abnormalities were noted. Where Gadolinium was given no abnormal enhancement was observed. These cases add to the literature and suggest that these prominent canals are largely asymptomatic and should be viewed as normal variants. Copyright (2002) Blackwell Science Pty Ltd

  20. Mercury in feathers of Swedish gyrfalcons, Falco rusticolus, in relation to diet

    International Nuclear Information System (INIS)

    Lindberg, P.

    1984-01-01

    The gyrfalcon (Falco rusticolus) is mainly a resident bird breeding in mountain areas in Fennoscandia. The population (estimated to 300-500 pairs) probably fluctuates according to the presence of willow grouse (Lagopus lagopus) and ptarmigan (Lagopus mutus). Little is known about pollutant levels in Fennoscandian gyrfalcons. Previous studies found low levels of DDE, PCB and mercury in organs from six Norwegian gyrfalcons. In this paper the author has included additional information on mercury levels, based on feather analyses from a few nests in northern Sweden. The use of feathers is a simple method to monitor mercury levels without sacrificing the birds. Food habits were checked by analyzing food remains at and near the nests

  1. Resistance of Feather-Associated Bacteria to Intermediate Levels of Ionizing Radiation near Chernobyl

    OpenAIRE

    Ruiz-Gonz?lez, Mario Xavier; Czirj?k, G?bor ?rp?d; Genevaux, Pierre; M?ller, Anders Pape; Mousseau, Timothy Alexander; Heeb, Philipp

    2016-01-01

    Ionizing radiation has been shown to produce negative effects on organisms, although little is known about its ecological and evolutionary effects. As a study model, we isolated bacteria associated with feathers from barn swallows Hirundo rustica from three study areas around Chernobyl differing in background ionizing radiation levels and one control study site in Denmark. Each bacterial community was exposed to four different ? radiation doses ranging from 0.46 to 3.96 kGy to test whether ch...

  2. Rockets and feathers meet Joseph: Reinvestigating the oil-gasoline asymmetry on the international markets

    Czech Academy of Sciences Publication Activity Database

    Krištoufek, Ladislav; Luňáčková, P.

    2015-01-01

    Roč. 49, č. 1 (2015), s. 1-8 ISSN 0140-9883 R&D Projects: GA ČR(CZ) GP14-11402P Grant - others:GA ČR(CZ) GAP402/11/0948 Program:GA Institutional support: RVO:67985556 Keywords : Rockets and feathers * Asymmetry * Gasoline * Crude oil * Cointegration Subject RIV: AH - Economics Impact factor: 2.862, year: 2015 http://library.utia.cas.cz/separaty/2015/E/kristoufek-0452312.pdf

  3. [Dynamics of infection of Fringilla coelebs chaffinch nestlings with feather mites (Acari: Analgoidea)].

    Science.gov (United States)

    Mironov, S V; Malyshev, L L

    2002-01-01

    A process of infecting the chaffinch nestlings Fringilla coelebs with three analgoid feather mites, Analges passerinus L., 1758, Monojoubertia microphylla (Robin, 1877), and Pteronyssoides striatus (Robin, 1977), commonly occurred on this bird species was investigated. 15 nests contained totally 65 nestlings, from 2 to 6 individuals in a brood, have been examined from the day of hatching till 11th day. Observations were held in the neighbourhood of the bird banding station "Rybachy" (Russia, Kaliningrad Province) in June of 1982. Number of mites on alive nestlings taken temporarily from their nest was counted by means of binocular lens under the magnification x12.5 and x25. The nestlings receive the mites from the chaffinch female during the night time, when the female sits together with the young birds and heats them. In the condition of this prolonged direct contact the mites migrate from the female onto the nestlings. As it was shown in our study of seasonal dynamics of mites on the chaffinch (Mironov, 2000), the chaffinch female only gives its mites to young generation and looses about three quarter of its mite micropopulation during the nesting period (June), hile in the chaffinch males the number of mites continues to increase during all summer. The infections with three feather mite species happen in the second part of the nestling's stay in the nest. The starting time of this process, its intensity, and sex and age structure of mite micropopulations on the nestlings just before their leaving the nest are different in the mite species examined. These peculiarities of feather mite species are determined by the biology of examined species, and first of all by their morphological characteristic and specialisation to different microhabitats, i.e. certain structural zones of plumage. Pteronyssoides striatus (Pteronyssidae) is rather typical mite specialised to feathers with vanes. In adult birds with completely developed plumage this species occupies the ventral

  4. Colour-producing [beta]-keratin nanofibres in blue penguin (Eudyptula minor) feathers

    Energy Technology Data Exchange (ETDEWEB)

    D; Alba, Liliana; Saranathan, Vinodkumar; Clarke, Julia A.; Vinther, Jakob A.; Prum, Richard O.; Shawkey, Matthew D. (Yale); (Akron); (Texas)

    2012-03-26

    The colours of living organisms are produced by the differential absorption of light by pigments (e.g. carotenoids, melanins) and/or by the physical interactions of light with biological nanostructures, referred to as structural colours. Only two fundamental morphologies of non-iridescent nanostructures are known in feathers, and recent work has proposed that they self-assemble by intracellular phase separation processes. Here, we report a new biophotonic nanostructure in the non-iridescent blue feather barbs of blue penguins (Eudyptula minor) composed of parallel {beta}-keratin nanofibres organized into densely packed bundles. Synchrotron small angle X-ray scattering and two-dimensional Fourier analysis of electron micrographs of the barb nanostructure revealed short-range order in the organization of fibres at the appropriate size scale needed to produce the observed colour by coherent scattering. These two-dimensional quasi-ordered penguin nanostructures are convergent with similar arrays of parallel collagen fibres in avian and mammalian skin, but constitute a novel morphology for feathers. The identification of a new class of {beta}-keratin nanostructures adds significantly to the known mechanisms of colour production in birds and suggests additional complexity in their self-assembly.

  5. Soluble proteins from fowl feather keratin. II. Isolation of some proteins from barbs.

    Science.gov (United States)

    Murayama, K; Akahane, K; Murozono, S

    1977-01-01

    Four fractions, GF-1, 2, 3, and 4, which had been separated from S-carboxymethylated (SCM-) proteins of fowl feathers by gel filtration, were each chromatographed on a DEAE-cellulose column in 0.05 M Tris-HCl buffer (pH 8.5) containing 8 M urea. The major fraction, GF-3, was further separated into seven peaks; the first four were shown to be single components by polyacrylamide disc gel electrophoresis. Chromatograms of GF-1 and 2 showed broad peaks which appeared at nearly the same volume as in GF-3. The components from GF-3 had very similar amino acid compositions except that the SCM-cysteine content showed a tendency to increase in the order of elution from the column. SCM-extract prepared from barbs of the wing feathers of a fowl was more heterogeneous than that taken from the body feathers. A combination of gel filtration on Sephadex G-75 and chromatography on DEAE-cellulose was found to be more effective for the isolation of soluble SCM-proteins.

  6. Two-dimensional Fourier analysis of the spongy medullary keratin of structurally coloured feather barbs

    Science.gov (United States)

    Prum, R. O.; Torres, R.; Williamson, S.; Dyck, J.

    1999-01-01

    We conducted two-dimensional (2D) discrete Fourier analyses of the spatial variation in refractive index of the spongy medullary keratin from four different colours of structurally coloured feather barbs from three species of bird: the rose-faced lovebird, Agapornis roseicollis (Psittacidae), the budgerigar, Melopsittacus undulatus (Psittacidae), and the Gouldian finch, Poephila guttata (Estrildidae). These results indicate that the spongy medullary keratin is a nanostructured tissue that functions as an array of coherent scatterers. The nanostructure of the medullary keratin is nearly uniform in all directions. The largest Fourier components of spatial variation in refractive index in the tissue are of the appropriate size to produce the observed colours by constructive interference alone. The peaks of the predicted reflectance spectra calculated from the 2D Fourier power spectra are congruent with the reflectance spectra measured by using microspectrophotometry. The alternative physical models for the production of these colours, the Rayleigh and Mie theories, hypothesize that medullary keratin is an incoherent array and that scattered waves are independent in phase. This assumption is falsified by the ring-like Fourier power spectra of these feathers, and the spacing of the scattering air vacuoles in the medullary keratin. Structural colours of avian feather barbs are produced by constructive interference of coherently scattered light waves from the optically heterogeneous matrix of keratin and air in the spongy medullary layer.

  7. Study on elements concentrations on seabird feathers by instrumental neutron activation analysis

    Energy Technology Data Exchange (ETDEWEB)

    Theophilo, Carolina Y.S.; Moreira, Edson G. [Instituto de Pesquisas Energeticas e Nucleares (IPEN-CNEN/SP), São Paulo, SP (Brazil); Figueira, Rubens C.L.; Colabuono, Fernanda I., E-mail: carolina.theophilo@gmail.com, E-mail: emoreira@ipen.br, E-mail: rfigueira@usp.br, E-mail: ficolabuono@gmail.com [Universidade de São Paulo (USP), São Paulo, SP (Brazil). Instituto Oceanográfico

    2017-07-01

    Seabirds are very sensitive to environmental changes and because of their large longevity they are also sensitive to cumulative impacts. These birds usually occupy the higher trophic levels. White-chinned petrel (Procellaria aequinoctialis) and black-browed albatross (Thalassarche melanophris) are Procellariiformes, which is a seabird order, composed of 4 families. In the last years, researches are being done and actions are being taken to reduce the mortality of albatrosses and petrels caused by human activities. Due to the great ecological importance of these birds and the developed work with Procellariiformes, this study purpose is to quantify the Br, Cl, Cu, K, Mg, Mn, Na and V elements in white-chinned petrel and black-browed albatross feathers. Bird specimens were killed accidentally by pelagic longline fisheries operating off southern Brazil. Feathers were cleaned with acetone and then milled in a cryogenic mill. Instrumental Neutron Activation Analysis (INAA) was used for quantification of the element concentrations and measurements of induced activities were performed in a HPGe detector for gamma ray spectrometry. The obtained results on feathers showed that concentrations in these birds are not higher than others studies with the same species and, with exception of Br, there are no significant differences between elements mean concentrations in the two seabirds. (author)

  8. Multiple UV reflectance peaks in the iridescent neck feathers of pigeons

    Science.gov (United States)

    McGraw, Kevin J.

    Recent studies of colorful plumage signals in birds have been aided by the finding that birds can see ultraviolet (UV) light and thus may communicate using colors invisible to humans. Some of the pioneering and more pivotal work on avian color vision was performed with domestic pigeons (Columba livia), yet surprisingly there have been few detailed reports of the UV-reflecting properties of pigeon feathers. Here, I use UV-VIS fiber-optic spectrometry to document the full-spectrum reflectance characteristics of iridescent purple and green neck plumage in pigeons. Neck feathers that appear purple to the human eye exhibit four reflectance peaks-two in the UV and one in the blue and red regions-and thus exhibit a UV-purple hue. Neck feathers that appear green to the human eye are characterized by five spectral peaks: two in the UV (UVA and UVB), a predominant green peak, and secondary violet and red peaks, conferring a UV-purple-green color. Such elaborate UV coloration suggests that birds may use an even more complex and `hidden' UV signaling system than previously thought.

  9. Chicken feather peptone: A new alternative nitrogen source for pigment production by Monascus purpureus.

    Science.gov (United States)

    Orak, Tugba; Caglar, Ozge; Ortucu, Serkan; Ozkan, Hakan; Taskin, Mesut

    2018-04-10

    Peptones are accepted as one of the most favourable nitrogen sources supporting pigment synthesis in Monascus purpureus. The present study was performed to test the feasibility of chicken feather peptone (CFP) as nitrogen source for pigment production from M. purpureus ATCC16365. CFP was compared with fish peptone (FP) and protease peptone (PP) in order to elucidate its effectiveness on pigment production. CFP was prepared from waste feathers using hydrolysis (KOH) and neutralization (H 2 SO 4 ) methods. The protein content of CFP was determined as 67.2 g/100 g. Optimal concentrations of CFP and glucose for pigment production were determined as 3 and 20 g/L, respectively. A medium pH of 5.5 and an incubation period of 7-days were found to be more favourable for pigment production. In CFP, PP and FP media, yellow pigment absorbances were 2.819, 2.870 and 2.831, red pigment absorbances were 2.709, 2.304 and 2.748, and orange pigment absorbances were 2.643, 2.132 and 2.743, respectively. Sugar consumption and mycelia growth showed the similar trends in CFP, FP and PP media. This study indicates that the peptone from chicken feathers may be a good nutritional substrate for pigment production from M. purpureus. Copyright © 2018 Elsevier B.V. All rights reserved.

  10. Performance and Heterosis of Indigenous Chicken Crossbreed (Naked Neck x Frizzled Feather In The Humid Tropics

    Directory of Open Access Journals (Sweden)

    Jeremiah Monday Nwenya

    2017-12-01

    Full Text Available Forty-four (44 birds (about 50 weeks old male and female inbred naked necked and frizzle feathered chickens were crossed to generate F1 crossbred chicken that were used to evaluate the performance and heterosis effects. Data taken on 180 chicks (97 NN and 83 FF day-old chick weight (BWT0, body weight (BWT, daily average feed intake (AFI, feed conversion ratio (FCR, brooding and rearing mortalities, linear body measurements (LBM: body length, wing length, keel length, shank length and breast width were used to estimate heterosis and performance of F1 progenies. Results of the experiment showed positive heterosis with significant differences among the F1 progenies over their parents in body weight, average feed intake and feed conversion ratio. The reciprocal cross (i.e. frizzle feather rooster x naked neck hen showed a significant improvement in their performances genetically, explaining that better results are achieved through crossbreeding of these indigenous breeds. With reference to their body linear parameters, the reciprocal cross of naked neck and frizzle feathered chickens developed higher body length, whereas the main crosses performed better in their wing length, keel length, shank length and body width respectively, mainly after 8 weeks suggesting that earlier performance was attributable to maternal influences.

  11. Deadly hairs, lethal feathers--convergent evolution of poisonous integument in mammals and birds.

    Science.gov (United States)

    Plikus, Maksim V; Astrowski, Aliaksandr A

    2014-07-01

    Hairs and feathers are textbook examples of the convergent evolution of the follicular appendage structure between mammals and birds. While broadly recognized for their convergent thermoregulatory, camouflage and sexual display functions, hairs and feathers are rarely thought of as deadly defence tools. Several recent studies, however, show that in some species of mammals and birds, the integument can, in fact, be a de facto lethal weapon. One mammalian example is provided by African crested rats, which seek for and chew on the bark of plants containing the highly potent toxin, ouabain. These rats then coat their fur with ouabain-containing saliva. For efficient toxin retention, the rodents have evolved highly specialized fenestrated and mostly hollow hair shafts that soak up liquids, which essentially function as wicks. On the avian side of the vertebrate integumental variety spectrum, several species of birds of New Guinea have evolved resistance to highly potent batrachotoxins, which they acquire from their insect diet. While the mechanism of bird toxicity remains obscure, in a recently published issue of the journal, Dumbacher and Menon explore the intriguing idea that to achieve efficient storage of batrachotoxins in their skin, some birds exploit the basic permeability barrier function of their epidermis. Batrachotoxins become preferentially sequestered in their epidermis and are then transferred to feathers, likely through the exploitation of specialized avian lipid-storing multigranular body organelles. Here, we discuss wider implications of this intriguing concept. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  12. Colour-producing β-keratin nanofibres in blue penguin (Eudyptula minor) feathers

    Science.gov (United States)

    D'Alba, Liliana; Saranathan, Vinodkumar; Clarke, Julia A.; Vinther, Jakob A.; Prum, Richard O.; Shawkey, Matthew D.

    2011-01-01

    The colours of living organisms are produced by the differential absorption of light by pigments (e.g. carotenoids, melanins) and/or by the physical interactions of light with biological nanostructures, referred to as structural colours. Only two fundamental morphologies of non-iridescent nanostructures are known in feathers, and recent work has proposed that they self-assemble by intracellular phase separation processes. Here, we report a new biophotonic nanostructure in the non-iridescent blue feather barbs of blue penguins (Eudyptula minor) composed of parallel β-keratin nanofibres organized into densely packed bundles. Synchrotron small angle X-ray scattering and two-dimensional Fourier analysis of electron micrographs of the barb nanostructure revealed short-range order in the organization of fibres at the appropriate size scale needed to produce the observed colour by coherent scattering. These two-dimensional quasi-ordered penguin nanostructures are convergent with similar arrays of parallel collagen fibres in avian and mammalian skin, but constitute a novel morphology for feathers. The identification of a new class of β-keratin nanostructures adds significantly to the known mechanisms of colour production in birds and suggests additional complexity in their self-assembly. PMID:21307042

  13. Molecular evidence of keratin and melanosomes in feathers of the Early Cretaceous bird Eoconfuciusornis.

    Science.gov (United States)

    Pan, Yanhong; Zheng, Wenxia; Moyer, Alison E; O'Connor, Jingmai K; Wang, Min; Zheng, Xiaoting; Wang, Xiaoli; Schroeter, Elena R; Zhou, Zhonghe; Schweitzer, Mary H

    2016-12-06

    Microbodies associated with feathers of both nonavian dinosaurs and early birds were first identified as bacteria but have been reinterpreted as melanosomes. Whereas melanosomes in modern feathers are always surrounded by and embedded in keratin, melanosomes embedded in keratin in fossils has not been demonstrated. Here we provide multiple independent molecular analyses of both microbodies and the associated matrix recovered from feathers of a new specimen of the basal bird Eoconfuciusornis from the Early Cretaceous Jehol Biota of China. Our work represents the oldest ultrastructural and immunological recognition of avian beta-keratin from an Early Cretaceous (∼130-Ma) bird. We apply immunogold to identify protein epitopes at high resolution, by localizing antibody-antigen complexes to specific fossil ultrastructures. Retention of original keratinous proteins in the matrix surrounding electron-opaque microbodies supports their assignment as melanosomes and adds to the criteria employable to distinguish melanosomes from microbial bodies. Our work sheds new light on molecular preservation within normally labile tissues preserved in fossils.

  14. Traceability of poultry viscera meal by stable isotopes in broiler feathers

    International Nuclear Information System (INIS)

    Araujo, Priscila Cavalca de; Sartori, Jose Roberto; Pezzato, Antonio Celso; Stradiotti, Ana Cristina; Pelicia, Vanessa Cristina; Ducatti, Carlos

    2011-01-01

    The objective of this work was to evaluate the presence of poultry viscera meal (VM) in the diet of broiler chickens, through the feather analyses by stable isotopes of carbon ( 13 C/ 12 C) and nitrogen ( 15 N/ 14 N) and mass spectrophotometry. Seven hundred and twenty Cobb male broiler chicks were subjected to the following treatments: vegetable diet based on corn and soybean meal, from 1 to 42 days of age; diet with 8% poultry viscera meal, from 1 to 42 days of age; vegetable diet from 1 to 21 days, and diet with VM from 22 to 42 days; vegetable diet from 1 to 35 days, and diet with VM from 36 to 42 days; diet with VM from 1 to 21 days and, and vegetable diet from 22 to 42 days; diet with VM from 1 to 35 days, and vegetable diet from 36 to 42 days. Feather samples were collected from four birds per treatment at 7, 14, 21, 28, 35 and 42 days of age, which were subjected to isotopic analysis for carbon ( 13 C/ 12 C) and nitrogen ( 15 N/ 14 N) by mass spectrometry. The use of the stable C and N isotope technique in feathers allow the VM detection in broiler chicken diet after 21 days of VM inclusion. (author)

  15. [Breeding biology of the whiskered auklet (Aethia pygmaea): incubation, chick growth, and feather ontogenesis].

    Science.gov (United States)

    Koniukhov, N B; Zubakin, V A; Williams, J; Fischer, J

    2000-01-01

    This is the second publication on the results of studies of the whiskered auklet breeding biology on Buldir Island. In 1993, according to the time of chick hatching the egg-laying period began in late April-early May. The single egg was incubated by both parents, which relieved each other once a day, usually at early night. Among the chicks under observation, the first hatched on June 11; the median of hatching was on June 17. After hatching, the egg shell usually remained in the nest. The chick was continuously brooded by one of parents for the first several days but since the age of 7-9 days, it stayed in the nest by itself during the daytime. Each parent fed the chick once a day, at early night, although occasional feedings were recorded also during daytime and at dawn. A newly hatched chick was covered by typical embryonal (natal) down. The remiges, rectrices, their coverts, and large feathers on pteryla humeralis had a mesoptile stage during their growth (the second down generation). The juvenile plumage consisted of semiplumes of types I and II and contour feathers of type I and, possibly, type II. In fledglings, the ornamental feathers were underdeveloped: the crest was absent and facial plumes only began growing. By reaching 100 g, the chicks left their nests at the age of about 37 days. A longer nesting period than in other Aethia auklets appears to be related to a low feeding rate due to the nocturnal activity in the colony.

  16. Study on elements concentrations on seabird feathers by instrumental neutron activation analysis

    International Nuclear Information System (INIS)

    Theophilo, Carolina Y.S.; Moreira, Edson G.; Figueira, Rubens C.L.; Colabuono, Fernanda I.

    2017-01-01

    Seabirds are very sensitive to environmental changes and because of their large longevity they are also sensitive to cumulative impacts. These birds usually occupy the higher trophic levels. White-chinned petrel (Procellaria aequinoctialis) and black-browed albatross (Thalassarche melanophris) are Procellariiformes, which is a seabird order, composed of 4 families. In the last years, researches are being done and actions are being taken to reduce the mortality of albatrosses and petrels caused by human activities. Due to the great ecological importance of these birds and the developed work with Procellariiformes, this study purpose is to quantify the Br, Cl, Cu, K, Mg, Mn, Na and V elements in white-chinned petrel and black-browed albatross feathers. Bird specimens were killed accidentally by pelagic longline fisheries operating off southern Brazil. Feathers were cleaned with acetone and then milled in a cryogenic mill. Instrumental Neutron Activation Analysis (INAA) was used for quantification of the element concentrations and measurements of induced activities were performed in a HPGe detector for gamma ray spectrometry. The obtained results on feathers showed that concentrations in these birds are not higher than others studies with the same species and, with exception of Br, there are no significant differences between elements mean concentrations in the two seabirds. (author)

  17. Using scale and feather traits for module construction provides a functional approach to chicken epidermal development.

    Science.gov (United States)

    Bao, Weier; Greenwold, Matthew J; Sawyer, Roger H

    2017-11-01

    Gene co-expression network analysis has been a research method widely used in systematically exploring gene function and interaction. Using the Weighted Gene Co-expression Network Analysis (WGCNA) approach to construct a gene co-expression network using data from a customized 44K microarray transcriptome of chicken epidermal embryogenesis, we have identified two distinct modules that are highly correlated with scale or feather development traits. Signaling pathways related to feather development were enriched in the traditional KEGG pathway analysis and functional terms relating specifically to embryonic epidermal development were also enriched in the Gene Ontology analysis. Significant enrichment annotations were discovered from customized enrichment tools such as Modular Single-Set Enrichment Test (MSET) and Medical Subject Headings (MeSH). Hub genes in both trait-correlated modules showed strong specific functional enrichment toward epidermal development. Also, regulatory elements, such as transcription factors and miRNAs, were targeted in the significant enrichment result. This work highlights the advantage of this methodology for functional prediction of genes not previously associated with scale- and feather trait-related modules.

  18. Effect of Sex-linked Feathering Genes on Body Weight, Age At Sexual Maturity, Feed Intake and Subsequent Laying Performance of Baladi Chickens

    Directory of Open Access Journals (Sweden)

    A. AI-Sobayel

    1997-01-01

    Full Text Available A total of 320 twenty week-old slow and rapid feathering Saudi Arabian Baladi pullers were used to assess the effect of sex-linked feathering genes on body weight, age at sexual maturity, feed intake and subsequent laying performance. Similar numbers of rapid feathering Leghorns pullets were included in the study for the purpose of comparison. The experimental birds of each genotypic group were randomly divided into four replicates and subjected to standard management practices. Slow feathering Baladi pullers had higher (P<0.05 adult body weight, rate of mortality, and feed intake and a similar age at sexual maturity but showed lower (P< 0.05 hen-day, and hen-housed egg production and feed conversion compared with rapid feathering Baladi pullets. Rapid feathering Leghorns had higher (P<0.05 adult body weight. age at sexual maturity, hen-day egg production, rate of mortality and feed intake and lower feed intake/kg eggs than rapid and slow feathering Baladi. However, rapid feathering Baladi and Leghorns had similar hen-housed egg production and feed intake per dozen eggs and had better (l’<0.05' performance than slow feathering Baladi.

  19. [Determination of 10 elements in the feather of brown-eared pheasant by ICP and AAS].

    Science.gov (United States)

    Wu, Yu-Zhen; Zhang, Feng; Wang, Meng-Ben; Zhao, Gen-Gui

    2008-03-01

    Crossoptilon mantchuricum (brown-eared pheasant) is an endemic to northern China and one of the state first-protection animals, which is now confined to scattered localities in Guandi Mountains, Guancen Mountains, Luliang Ranges of western Shanxi, and the mountains of north-western Hebei, western Beijing and central Shaanxi. Its range is fragmented by habitat loss because of human activity and other intervention, and isolated populations are resulting in facing the extinction risk from further forest destroyed and other pressures. The trace elements are very important to the growth and development of brown-eared pheasant, and these elements in the feather are closely correlated to the contents in the organs of the bird. By research on the elements contents in the feather, the authors are able to get more information about the growth, development, reproduction, immunity and metabolism function for this bird. The aim of this study is to try providing scientific basis for further enhancing the protection and the artificial breeding. Ten elements including Mo, Zn, Ni, Fe, Mn, Cr, Cu, K, Pb and Cd were determined in the feather of brown-eared pheasant by ICP and AAS, respectively. For the analysis two samples were from Luya Mountain Natural Reserve and Pangquangou Natural Reserve, and one was from Taiyuan Zoo, Shanxi. The contents of the elements in the feather of wild and captive brown-eared pheasants were compared each other. The results showed that the contents of the eight elements the feather from the Zoo were lower than those from Luya Mountain Natural Reserve and Pangquangou Natural Reserve. Moreover, Fe is the highest among those ten elements, Cd was not found, and Mo and Cr were much lower than the others. It is suggested that varying habitats have obvious effects on the elements contents of wild bird body, and wild habitant is more beneficial to the bird growth and development. Applying the results to wild animal management would be favorable to the protection

  20. Morphology and Dynamics of Solar Prominences from 3D MHD Simulations

    Science.gov (United States)

    Terradas, J.; Soler, R.; Luna, M.; Oliver, R.; Ballester, J. L.

    2015-01-01

    In this paper we present a numerical study of the time evolution of solar prominences embedded in sheared magnetic arcades. The prominence is represented by a density enhancement in a background-stratified atmosphere and is connected to the photosphere through the magnetic field. By solving the ideal magnetohydrodynamic equations in three dimensions, we study the dynamics for a range of parameters representative of real prominences. Depending on the parameters considered, we find prominences that are suspended above the photosphere, i.e., detached prominences, but also configurations resembling curtain or hedgerow prominences whose material continuously connects to the photosphere. The plasma-β is an important parameter that determines the shape of the structure. In many cases magnetic Rayleigh-Taylor instabilities and oscillatory phenomena develop. Fingers and plumes are generated, affecting the whole prominence body and producing vertical structures in an essentially horizontal magnetic field. However, magnetic shear is able to reduce or even to suppress this instability.

  1. MORPHOLOGY AND DYNAMICS OF SOLAR PROMINENCES FROM 3D MHD SIMULATIONS

    Energy Technology Data Exchange (ETDEWEB)

    Terradas, J.; Soler, R.; Oliver, R.; Ballester, J. L. [Departament de Física, Universitat de les Illes Balears, E-07122 Palma de Mallorca (Spain); Luna, M., E-mail: jaume.terradas@uib.es [Instituto de Astrofísica de Canarias, E-38200 La Laguna, Tenerife (Spain)

    2015-01-20

    In this paper we present a numerical study of the time evolution of solar prominences embedded in sheared magnetic arcades. The prominence is represented by a density enhancement in a background-stratified atmosphere and is connected to the photosphere through the magnetic field. By solving the ideal magnetohydrodynamic equations in three dimensions, we study the dynamics for a range of parameters representative of real prominences. Depending on the parameters considered, we find prominences that are suspended above the photosphere, i.e., detached prominences, but also configurations resembling curtain or hedgerow prominences whose material continuously connects to the photosphere. The plasma-β is an important parameter that determines the shape of the structure. In many cases magnetic Rayleigh-Taylor instabilities and oscillatory phenomena develop. Fingers and plumes are generated, affecting the whole prominence body and producing vertical structures in an essentially horizontal magnetic field. However, magnetic shear is able to reduce or even to suppress this instability.

  2. Bacterial recovery from breast skin of genetically feathered and featherless broiler carcasses immediately following scalding and picking.

    Science.gov (United States)

    Buhr, R J; Berrang, M E; Cason, J A

    2003-10-01

    Genetically feathered and featherless sibling broilers selected for matched BW were killed, scalded, and defeathered to determine the consequences of feathers and empty feather follicles on the recovery of bacteria from carcass breast skin. In trial 1, the vents of all carcasses were plugged and sutured before scalding to prevent the expulsion of cloacal contents during picking. In trial 2, half of the carcasses had their vents plugged and sutured. Immediately after defeathering, breast skin was aseptically removed, and bacteria associated with it were enumerated. In trial 1, the levels of bacteria recovered did not differ between feathered and featherless carcasses: Campylobacter log10 1.4 cfu/mL of rinse, coliform log10 1.8, Escherichia coli log10 1.6, and total aerobic bacteria log10 3.1. In trial 2, the carcasses that had vents plugged and sutured had lower levels of all four types of bacteria (differences of Campylobacter log10 0.7 cfu/mL, coliform log10 1.8, E. coli log10 1.7, and total aerobic bacteria log10 0.5) than those carcasses with open vents. The lower levels of bacteria recovered from carcasses with the vents plugged and sutured during picking enabled detection of small but significant differences between feathered and featherless carcasses. The level of coliform and E. coli recovered was slightly higher by log10 0.7 cfu for feathered carcasses, but featherless carcasses had marginally higher levels of total aerobic bacteria by log10 0.4 cfu. Feathered and featherless carcasses with open vents during picking did not differ in the levels of recovery of coliform, E. coli, and total aerobic bacteria from breast skin.

  3. Mercury and other metals in eggs and feathers of glaucous-winged gulls (Larus glaucescens) in the Aleutians

    Science.gov (United States)

    Gochfeld, Michael; Jeitner, Christian; Burke, Sean; Volz, Conrad D.; Snigaroff, Ronald; Snigaroff, Daniel; Shukla, Tara; Shukla, Sheila

    2014-01-01

    Levels of mercury and other contaminants should be lower in birds nesting on isolated oceanic islands and at high latitudes without any local or regional sources of contamination, compared to more urban and industrialized temperate regions. We examined concentrations of arsenic, cadmium, chromium, lead, manganese, mercury and selenium in the eggs, and the feathers of fledgling and adult glaucous-winged gulls (Larus glaucescens) nesting in breeding colonies on Adak, Amchitka, and Kiska Islands in the Aleutian Chain of Alaska in the Bering Sea/North Pacific. We tested the following null hypotheses: 1) There were no differences in metal levels among eggs and feathers of adult and fledgling glaucous-winged gulls, 2) There were no differences in metal levels among gulls nesting near the three underground nuclear test sites (Long Shot 1965, Milrow 1969, Cannikin 1971) on Amchitka, 3) There were no differences in metal levels among the three islands, and 4) There were no gender-related differences in metal levels. All four null hypotheses were rejected at the 0.05 level, although there were few differences among the three test sites on Amchitka. Eggs had the lowest levels of cadmium, lead, and mercury, and the feathers of adults had the lowest levels of selenium. Comparing only adults and fledglings, adults had higher levels of cadmium, chromium, lead and mercury, and fledglings had higher levels of arsenic, manganese and selenium. There were few consistent interisland differences, although levels were generally lower for eggs and feathers from gulls on Amchitka compared to the other islands. Arsenic was higher in both adult feathers and eggs from Amchitka compared to Adak, and chromium and lead were higher in adult feathers and eggs from Adak compared to Amchitka. Mercury and arsenic, and chromium and manganese levels were significantly correlated in the feathers of both adult and fledgling gulls. The feathers of males had significantly higher levels of chromium and

  4. Feather barbs as a good source of mtDNA for bird species identification in forensic wildlife investigations.

    Science.gov (United States)

    Speller, Camilla F; Nicholas, George P; Yang, Dongya Y

    2011-07-28

    The ability to accurately identify bird species is crucial for wildlife law enforcement and bird-strike investigations. However, such identifications may be challenging when only partial or damaged feathers are available for analysis. By applying vigorous contamination controls and sensitive PCR amplification protocols, we found that it was feasible to obtain accurate mitochondrial (mt)DNA-based species identification with as few as two feather barbs. This minimally destructive DNA approach was successfully used and tested on a variety of bird species, including North American wild turkey (Meleagris gallopavo), Canada goose (Branta canadensis), blue heron (Ardea herodias) and pygmy owl (Glaucidium californicum). The mtDNA was successfully obtained from 'fresh' feathers, historic museum specimens and archaeological samples, demonstrating the sensitivity and versatility of this technique. By applying appropriate contamination controls, sufficient quantities of mtDNA can be reliably recovered and analyzed from feather barbs. This previously overlooked substrate provides new opportunities for accurate DNA species identification when minimal feather samples are available for forensic analysis.

  5. The extent of the preserved feathers on the four-winged dinosaur Microraptor gui under ultraviolet light.

    Directory of Open Access Journals (Sweden)

    David W E Hone

    Full Text Available BACKGROUND: The holotype of the theropod non-avian dinosaur Microraptor gui from the Early Cretaceous of China shows extensive preservation of feathers in a halo around the body and with flight feathers associated with both the fore and hindlimbs. It has been questioned as to whether or not the feathers did extend into the halo to reach the body, or had disassociated and moved before preservation. This taxon has important implications for the origin of flight in birds and the possibility of a four-winged gliding phase. METHODOLOGY/PRINCIPAL FINDINGS: Examination of the specimen under ultraviolet light reveals that these feathers actually reach the body of the animal and were not disassociated from the bones. Instead they may have been chemically altered by the body tissues of the animal meaning that they did not carbonise close into the animal or more likely were covered by other decaying tissue, though evidence of their presence remains. CONCLUSIONS/SIGNIFICANCE: These UV images show that the feathers preserved on the slab are genuinely associated with the skeleton and that their arrangement and orientation is likely correct. The methods used here to reveal hidden features of the specimen may be applicable to other specimens from the fossil beds of Liaoning that produced Microraptor.

  6. Magnetic Field-Vector Measurements in Quiescent Prominences via the Hanle Effect: Analysis of Prominences Observed at Pic-Du-Midi and at Sacramento Peak

    Science.gov (United States)

    Bommier, V.; Leroy, J. L.; Sahal-Brechot, S.

    1985-01-01

    The Hanle effect method for magnetic field vector diagnostics has now provided results on the magnetic field strength and direction in quiescent prominences, from linear polarization measurements in the He I E sub 3 line, performed at the Pic-du-Midi and at Sacramento Peak. However, there is an inescapable ambiguity in the field vector determination: each polarization measurement provides two field vector solutions symmetrical with respect to the line-of-sight. A statistical analysis capable of solving this ambiguity was applied to the large sample of prominences observed at the Pic-du-Midi (Leroy, et al., 1984); the same method of analysis applied to the prominences observed at Sacramento Peak (Athay, et al., 1983) provides results in agreement on the most probable magnetic structure of prominences; these results are detailed. The statistical results were confirmed on favorable individual cases: for 15 prominences observed at Pic-du-Midi, the two-field vectors are pointing on the same side of the prominence, and the alpha angles are large enough with respect to the measurements and interpretation inaccuracies, so that the field polarity is derived without any ambiguity.

  7. Automatic feathering of split fields for step-and-shoot intensity modulated radiation therapy

    International Nuclear Information System (INIS)

    Dogan, Nesrin; Leybovich, Leonid B; Sethi, Anil; Emami, Bahman

    2003-01-01

    Due to leaf travel range limitations of the Varian Dynamic Multileaf Collimator (DMLC) system, an IMRT field width exceeding 14.5 cm is split into two or more adjacent abutting sub-fields. The abutting sub-fields are then delivered as separate treatment fields. The accuracy of the delivery is very sensitive to multileaf positioning accuracy. The uncertainties in leaf and carriage positions cause errors in the delivered dose (e.g., hot or cold spots) along the match line of abutting sub-fields. The dose errors are proportional to the penumbra slope at the edge of each sub-field. To alleviate this problem, we developed techniques that feather the split line of IMRT fields. Feathering of the split line was achieved by dividing IMRT fields into several sub-groups with different split line positions. A Varian 21EX accelerator with an 80-leaf DLMC was used for IMRT delivery. Cylindrical targets with varying widths (>14.5 cm) were created to study the split line positions. Seven coplanar 6 MV fields were selected for planning using the NOMOS-CORVUS TM system. The isocentre of the fields was positioned at the centre of the target volume. Verification was done in a 30 x 30 x 30 cm 3 polystyrene phantom using film dosimetry. We investigated two techniques to move the split line from its original position or cause feathering of them: (1) varying the isocentre position along the target width and (2) introduction of a 'pseudo target' outside of the patient (phantom). The position of the 'pseudo target' was determined by analysing the divergence of IMRT fields. For target widths of 14-28 cm, IMRT fields were automatically split into two sub-fields, and the split line was positioned along the centre of the target by CORVUS. Measured dose distributions demonstrated that the dose to the critical structure was 10% higher than planned when the split line crossed through the centre of the target. Both methods of modifying the split line positions resulted in maximum shifts of ∼1 cm

  8. Validating the use of intrinsic markers in body feathers to identify inter-individual differences in non-breeding areas of northern fulmars.

    Science.gov (United States)

    Quinn, Lucy R; Meharg, Andrew A; van Franeker, Jan A; Graham, Isla M; Thompson, Paul M

    Many wildlife studies use chemical analyses to explore spatio-temporal variation in diet, migratory patterns and contaminant exposure. Intrinsic markers are particularly valuable for studying non-breeding marine predators, when direct methods of investigation are rarely feasible. However, any inferences regarding foraging ecology are dependent upon the time scale over which tissues such as feathers are formed. In this study, we validate the use of body feathers for studying non-breeding foraging patterns in a pelagic seabird, the northern fulmar. Analysis of carcasses of successfully breeding adult fulmars indicated that body feathers moulted between September and March, whereas analyses of carcasses and activity patterns suggested that wing feather and tail feather moult occurred during more restricted periods (September to October and September to January, respectively). By randomly sampling relevant body feathers, average values for individual birds were shown to be consistent. We also integrated chemical analyses of body feather with geolocation tracking data to demonstrate that analyses of δ 13 C and δ 15 N values successfully assigned 88 % of birds to one of two broad wintering regions used by breeding adult fulmars from a Scottish study colony. These data provide strong support for the use of body feathers as a tool for exploring non-breeding foraging patterns and diet in wide-ranging, pelagic seabirds.

  9. The peacock's train (Pavo cristatus and Pavo cristatus mut. alba) II. The molecular parameters of feather keratin plasticity.

    Science.gov (United States)

    Weiss, Ingrid M; Schmitt, Karl P; Kirchner, Helmut O K

    2011-06-01

    Thermal activation analysis of plastic deformation of peacock tail feathers, by temperature changes and stress relaxation, gave for the keratin cortex an activation enthalpy of 1.78 ± 0.89 eV and an activation volume of 0.83 ± 0.13 nm³, for both the blue and the white subspecies. These values suggest that breaking of electrostatic bonds is responsible for plasticity in feather keratin. These might be bonds between keratin and nonkeratinous matrix or keratin-keratin cross-links. The mechanical properties of the rachis cortex are surprisingly uniform along the length of the feathers. Copyright © 2011 Wiley-Liss, Inc., A Wiley Company.

  10. The peacock's train (Pavo cristatus and Pavo cristatus mut. alba) I. structure, mechanics, and chemistry of the tail feather coverts.

    Science.gov (United States)

    Weiss, Ingrid M; Kirchner, Helmut O K

    2010-12-01

    The feathers in the train of the peacock serve not for flying but for sexual display. They are long, slender beams loaded in bending by their own weight. An outer circular conical shell, the cortex, is filled by a closed foam of 7.6% relative density, the medulla, both of feather keratin. Outer diameter and thickness of the cortex decrease linearly from the body toward the tip. This self-similar geometry leads to a division of labor. The cortex (longitudinal Young's modulus 3.3 GPa, transverse modulus 1 GPa) provides 96% of the longitudinal strength and bending rigidity of the feather. The medulla (Young's modulus 10 MPa) provides 96% of the transverse compressive rigidity. Fracture stress of the cortex, both longitudinal and transverse, is 120 MPa. Copyright © 2010 Wiley-Liss, Inc., A Wiley Company.

  11. Integument pattern formation involves genetic and epigenetic controls: feather arrays simulated by digital hormone models.

    Science.gov (United States)

    Jiang, Ting-Xin; Widelitz, Randall B; Shen, Wei-Min; Will, Peter; Wu, Da-Yu; Lin, Chih-Min; Jung, Han-Sung; Chuong, Cheng-Ming

    2004-01-01

    Pattern formation is a fundamental morphogenetic process. Models based on genetic and epigenetic control have been proposed but remain controversial. Here we use feather morphogenesis for further evaluation. Adhesion molecules and/or signaling molecules were first expressed homogenously in feather tracts (restrictive mode, appear earlier) or directly in bud or inter-bud regions ( de novo mode, appear later). They either activate or inhibit bud formation, but paradoxically colocalize in the bud. Using feather bud reconstitution, we showed that completely dissociated cells can reform periodic patterns without reference to previous positional codes. The patterning process has the characteristics of being self-organizing, dynamic and plastic. The final pattern is an equilibrium state reached by competition, and the number and size of buds can be altered based on cell number and activator/inhibitor ratio, respectively. We developed a Digital Hormone Model which consists of (1) competent cells without identity that move randomly in a space, (2) extracellular signaling hormones which diffuse by a reaction-diffusion mechanism and activate or inhibit cell adhesion, and (3) cells which respond with topological stochastic actions manifested as changes in cell adhesion. Based on probability, the results are cell clusters arranged in dots or stripes. Thus genetic control provides combinational molecular information which defines the properties of the cells but not the final pattern. Epigenetic control governs interactions among cells and their environment based on physical-chemical rules (such as those described in the Digital Hormone Model). Complex integument patterning is the sum of these two components of control and that is why integument patterns are usually similar but non-identical. These principles may be shared by other pattern formation processes such as barb ridge formation, fingerprints, pigmentation patterning, etc. The Digital Hormone Model can also be applied to

  12. A high prevalence of beak and feather disease virus in non-psittacine Australian birds.

    Science.gov (United States)

    Amery-Gale, Jemima; Marenda, Marc S; Owens, Jane; Eden, Paul A; Browning, Glenn F; Devlin, Joanne M

    2017-07-01

    Beak and feather disease virus (BFDV) is a circovirus and the cause of psittacine beak and feather disease (PBFD). This disease is characterized by feather and beak deformities and is a recognized threat to endangered Psittaciformes (parrots and cockatoos). The role that non-psittacine birds may play as reservoirs of infection is unclear. This study aimed to begin addressing this gap in our knowledge of PBFD. Liver samples were collected from birds presented to the Australian Wildlife Health Centre at Zoos Victoria's Healesville Sanctuary for veterinary care between December 2014 and December 2015, and tested for BFDV DNA using polymerase chain reaction coupled with sequencing and phylogenetic analyses.Results/Key findings. Overall BFDV was detected in 38.1 % of 210 birds. BFDV was detected at high prevalence (56.2 %) in psittacine birds, in the majority of cases without any observed clinical signs of PBFD. We also found that BFDV was more common in non-psittacine species than previously recognized, with BFDV detected at 20.0 % prevalence in the non-psittacine birds tested, including species with no clear ecological association with psittacines, and without showing any detectable clinical signs of BFDV infection. Further research to determine the infectivity and transmissibility of BFDV in non-psittacine species is indicated. Until such work is undertaken the findings from this study suggest that every bird should be considered a potential carrier of BFDV, regardless of species and clinical presentation. Veterinary clinics and wildlife rehabilitation facilities caring for birds that are susceptible to PBFD should reconsider biosecurity protocols aimed at controlling BFDV.

  13. Handheld XRF analysis of a 16th century Mexican Feather Headdress

    International Nuclear Information System (INIS)

    Karydas, A.G; Padilla-Alvarez, R.; Drozdenko, M.; Korn, M.; Moreno Guzmán, M.O.

    2014-01-01

    The 16th century feather headdress in the Weltmuseum Wien (WMW), an affiliated institution of the Kunsthistorisches Museum (KHM) in Vienna, is the most renowned of the few remaining pre-Columbian “Arte Plumaria” artefacts, which were made by feather artisans (Amantecas) using traditional techniques in the territory of present day Mexico. The recorded history of the headdress begins in 1596, when it is first mentioned in the estate inventory of the art collection of Archduke Ferdinand II of Tyrol at Ambras Castle. Due to its age, the variety of materials used, its history and former restoration treatments, the artefact is today one of the most sensitive and demanding care objects of the museum. Despite the object’s long history, very little documentation on past interventions exists. From 2010-2012, a binational research project between Mexico (Instituto Nacional de Antropología e Historia) and Austria (Weltmuseum Wien) performed a systematic investigation focused on the identification of manufacturing techniques and the various materials, the old restoration measures and its conservation. Handheld x-ray fluorescence (XRF) spectrometers are extremely useful for the study of art works in museum collections. The possibility of bringing the instrument to inspect the objects on-site facilitates the study of artefacts that cannot be moved either due to their extreme fragility or due to their large size and/or weight. In addition, non-destructive analysis constitutes a preferred alternative to invasive sampling techniques, which are usually not allowed in the study of unique or extremely valuable objects. The aim of the XRF analysis was twofold: to investigate the possible presence of inorganic toxic elements that could be associated to the use of pesticides in past conservation interventions and; to characterize the chemical composition of the authentic gold and the gilded brass ornaments, which were added in the 19th century. The results of the XRF analytical

  14. Photonic Crystals with an Eye Pattern Similar to Peacock Tail Feathers

    Directory of Open Access Journals (Sweden)

    Minghui Wang

    2016-08-01

    Full Text Available A facile fabrication of photonic crystals (PCs with an eye pattern similar to peacock tail feathers has been demonstrated by self-assembly of colloidal particles in a sandwich mode. The sandwich mode is formed by superhydrophilic flat substrate sandwiching the poly(styrene-methyl methacrylate-arylic acid (Poly(St-MMA-AA latex suspension (2 wt% by the hydrophobic one. The patterns are characterized by optical microscopy images, reflection spectra, and the relative scanning electronic microscope images. This work will provide beneficial help for the understanding of the self-assembly process of colloidal crystals.

  15. Primary feather molt of adult mourning doves in North and South Carolina

    Science.gov (United States)

    Haas, G.H.; Amend, S.R.

    1979-01-01

    Examination of 8,141 adult mourning doves (Zenaida macroura) in North and South Carolina revealed that substantial numbers complete primary feather molt in September. Adult mourning doves shed primaries at the rate of 1 per 14 days. No difference was found in this rate between sexes or among years, 1969-74. The initiation of molt differed from year to year, and female molt always preceded male molt. Available data show that southern doves complete primary molt a month earlier than northern doves. Therefore, age based on primary molt can be biased upward if all molt-complete wings from southern hunting samples are considered immature.

  16. [Study on a collagenase protocol to extract DNA from remnant feathers in edible bird's nest].

    Science.gov (United States)

    Wang, Ling-Li; Chen, Nian; Zhang, Wei-Wei; Wu, Guo-Hong; Lai, Xiao-Ping

    2013-08-01

    To establish a method for extracting genomic DNA from rudimental bird feather from the precious edible bird's nest (EBN) harvested from the swiftlet cave. Observed the EBN using endoscopic and studied the influence of adding collagenase on the extracting yield of DNA. PCR amplification and sequencing for the extraction was also conducted. Collagenase was used in addition to protease K which could substantively increase the DNA yield. The DNA extracted by this method could be used for PCR and other molecular biology analyses. This method can be applied to identify the species types in biological products, especially for animal tissue materials that rich in collagen.

  17. An analytical hierarchical model explaining the robustness and flaw-tolerance of the interlocking barb-barbule structure of bird feathers

    Science.gov (United States)

    Chen, Qiang; Gorb, Stanislav; Kovalev, Alexander; Li, Zhiyong; Pugno, Nicola

    2016-10-01

    Feathers can fulfill their aerodynamic function only if the pennaceous vane forms an airfoil stabilized by robust interlocking between barbules. Thus, revealing the robustness of the interlocking mechanical behavior of the barbules is very important to understand the function and long-term resilience of bird feathers. This paper, basing on the small- and large-beam deflection solutions, presents a hierarchical mechanical model for deriving the critical delamination conditions of the interlocking barbules between two adjacent barbs in bird feathers. The results indicate a high robustness and flaw-tolerant design of the structure. This work contributes to the understanding of the mechanical behavior of the robust interlocking barb-barbule structure of the bird feather, and provides a basis for design of feather-inspired materials with robust interlocking mechanism, such as advanced bio-inspired micro-zipping devices.

  18. Feather retention force in broilers ante-, peri-, and post-mortem as influenced by electrical and carbon dioxide stunning.

    Science.gov (United States)

    Buhr, R J; Cason, J A; Rowland, G N

    1997-11-01

    Stunning and slaughter trials were conducted to evaluate the influence of stunning method (electrical 50 V alternating current, CO2 gas: 0 to 40% for 90 s or 40 to 60% for 30 s) on feather retention force (FRF) in commercial broilers. Feathers from the pectoral, sternal, and femoral feather tracts were sampled with a force gauge before stunning (ante-mortem) and contralaterally either after stunning (peri-mortem from 0.5 to 4 min) or after stunning and bleeding (post-mortem from 2 to 6 min). Prior to stunning, ante-mortem FRF values varied among assigned stunning methods only for the pectoral (7%) feather tract. After stunning, peri-mortem FRF values were higher only for the sternal tract (11% for 40 to 60% CO2 for 30 s); whereas after stunning and bleeding, post-mortem FRF values were lower than ante- or peri-mortem only for the sternal tract (10% lower for 40 to 60% CO2 for 30 s). Peri- and post-mortem FRF values did not differ among stunning methods for the pectoral and femoral feather tracts. Small changes in FRF values occurred from ante-mortem to peri-mortem (-1 to +12%), and from ante-mortem to post-mortem (-2 to +8%) across stunning methods. A significant increase was determined for only the pectoral tract (7%) from ante- to peri-mortem across stunning methods. Electrically stunned broilers that were not bled gained weight in excess of the 36 feathers removed (0.16%), apparently due to body surface water pickup during the brine-stunning process, whereas CO2-stunned broilers lost weight due to excretion of cloacal contents (-0.31 to -0.98%). The change in body weight among stunning methods was significant (P defeathering efficiency may not differ after scalding.

  19. Chicken feather hydrolysate as an inexpensive complex nitrogen source for PHA production by Cupriavidus necator on waste frying oils.

    Science.gov (United States)

    Benesova, P; Kucera, D; Marova, I; Obruca, S

    2017-08-01

    The chicken feather hydrolysate (FH) has been tested as a potential complex nitrogen source for the production of polyhydroxyalkanoates by Cupriavidus necator H16 when waste frying oil was used as a carbon source. The addition of FH into the mineral salt media with decreased inorganic nitrogen source concentration improved the yields of biomass and polyhydrohyalkanoates. The highest yields were achieved when 10 vol.% of FH prepared by microwave-assisted alkaline hydrolysis of 60 g l -1 feather was added. In this case, the poly(3-hydroxybutyrate) (PHB) yields were improved by more than about 50% as compared with control cultivation. A positive impact of FH was also observed for accumulation of copolymer poly(3-hydroxybutyrate-co-3-hydroxyvalerate) when sodium propionate was used as a precursor. The copolymer has superior processing and mechanical properties in comparison with PHB homopolymer. The application of FH eliminated the inhibitory effect of propionate and resulted in altered content of 3-hydroxyvalerate (3HV) in copolymer. Therefore, the hydrolysed feather can serve as an excellent complex source of nitrogen for the polyhydroxyalkanoates (PHA) production. Moreover, by the combination of two inexpensive types of waste, such as waste frying oil and feather hydrolysate, it is possible to produce PHA with substantially improved efficiency and sustainability. Millions of tons of feathers, important waste product of poultry-processing industry, are disposed off annually without any further benefits. Thus, there is an inevitable need for new technologies that enable ecologically and economically sensible processing of this waste. Herein, we report that alkali-hydrolysed feathers can be used as a complex nitrogen source considerably improving polyhydroxyalkanoates production on waste frying oil employing Cupriavidus necator. © 2017 The Society for Applied Microbiology.

  20. Flight performance and feather quality: paying the price of overlapping moult and breeding in a tropical highland bird.

    Directory of Open Access Journals (Sweden)

    Maria Angela Echeverry-Galvis

    Full Text Available A temporal separation of energetically costly life history events like reproduction and maintenance of the integumentary system is thought to be promoted by selection to avoid trade-offs and maximize fitness. It has therefore remained somewhat of a paradox that certain vertebrate species can undergo both events simultaneously. Identifying potential costs of overlapping two demanding life history stages will further our understanding of the selection pressures that shape the temporal regulation of life history events in vertebrates. We studied free-living tropical Slaty brush-finches (Atlapetes schistaceus, in which individuals spontaneously overlap reproduction and moult or undergo both events in separation. To assess possible costs of such an overlap we quantified feather quality and flight performance of individuals in different states. We determined individual's life history state by measuring gonad size and scoring moult stage, and collected a newly grown 7(th primary wing feather for later analysis of feather quality. Finally, we quantified flight performance for each individual in the wild. Overlapping individuals produced lighter and shorter wing feathers than individuals just moulting, with females decreasing feather quality more strongly during the overlap than males. Moreover, overlapping individuals had a reduced flight speed during escape flights, while their foraging flight speed was unaffected. Despite overlappers being larger and having a smaller wing area, their lower body mass resulted in a similar wing load as in breeders or moulters. Individuals measured repeatedly in different states also showed significant decreases in feather quality and escape flight speed during the overlap. Reduced escape flight speed may represent a major consequence of the overlap by increasing predation risk. Our data document costs to undergoing two life history stages simultaneously, which likely arise from energetic trade-offs. Impairments in

  1. Genomic organization and molecular phylogenies of the beta (β keratin multigene family in the chicken (Gallus gallus and zebra finch (Taeniopygia guttata: implications for feather evolution

    Directory of Open Access Journals (Sweden)

    Sawyer Roger H

    2010-05-01

    Full Text Available Abstract Background The epidermal appendages of reptiles and birds are constructed of beta (β keratins. The molecular phylogeny of these keratins is important to understanding the evolutionary origin of these appendages, especially feathers. Knowing that the crocodilian β-keratin genes are closely related to those of birds, the published genomes of the chicken and zebra finch provide an opportunity not only to compare the genomic organization of their β-keratins, but to study their molecular evolution in archosaurians. Results The subfamilies (claw, feather, feather-like, and scale of β-keratin genes are clustered in the same 5' to 3' order on microchromosome 25 in chicken and zebra finch, although the number of claw and feather genes differs between the species. Molecular phylogenies show that the monophyletic scale genes are the basal group within birds and that the monophyletic avian claw genes form the basal group to all feather and feather-like genes. Both species have a number of feather clades on microchromosome 27 that form monophyletic groups. An additional monophyletic cluster of feather genes exist on macrochromosome 2 for each species. Expression sequence tag analysis for the chicken demonstrates that all feather β-keratin clades are expressed. Conclusions Similarity in the overall genomic organization of β-keratins in Galliformes and Passeriformes suggests similar organization in all Neognathae birds, and perhaps in the ancestral lineages leading to modern birds, such as the paravian Anchiornis huxleyi. Phylogenetic analyses demonstrate that evolution of archosaurian epidermal appendages in the lineage leading to birds was accompanied by duplication and divergence of an ancestral β-keratin gene cluster. As morphological diversification of epidermal appendages occurred and the β-keratin multigene family expanded, novel β-keratin genes were selected for novel functions within appendages such as feathers.

  2. CRITICAL HEIGHT FOR THE DESTABILIZATION OF SOLAR PROMINENCES: STATISTICAL RESULTS FROM STEREO OBSERVATIONS

    Energy Technology Data Exchange (ETDEWEB)

    Liu Kai; Wang Yuming; Wang Shui; Shen Chenglong, E-mail: ymwang@ustc.edu.cn [CAS Key Laboratory of Geospace Environment, Department of Geophysics and Planetary Sciences, University of Science and Technology of China, Hefei, Anhui 230026 (China)

    2012-01-10

    At which height is a prominence inclined to be unstable, or where is the most probable critical height for the prominence destabilization? This question was statistically studied based on 362 solar limb prominences well recognized by Solar Limb Prominence Catcher and Tracker from 2007 April to the end of 2009. We found that there are about 71% disrupted prominences (DPs), among which about 42% of them did not erupt successfully and about 89% of them experienced a sudden destabilization process. After a comprehensive analysis of the DPs, we discovered the following: (1) Most DPs become unstable at a height of 0.06-0.14 R{sub Sun} from the solar surface, and there are two most probable critical heights at which a prominence is very likely to become unstable, the first one is 0.13 R{sub Sun} and the second one is 0.19 R{sub Sun }. (2) An upper limit for the erupting velocity of eruptive prominences (EPs) exists, which decreases following a power law with increasing height and mass; accordingly, the kinetic energy of EPs has an upper limit too, which decreases as the critical height increases. (3) Stable prominences are generally longer and heavier than DPs, and not higher than 0.4 R{sub Sun }. (4) About 62% of the EPs were associated with coronal mass ejections (CMEs); but there is no difference in apparent properties between EPs associated with CMEs and those that are not.

  3. CRITICAL HEIGHT FOR THE DESTABILIZATION OF SOLAR PROMINENCES: STATISTICAL RESULTS FROM STEREO OBSERVATIONS

    International Nuclear Information System (INIS)

    Liu Kai; Wang Yuming; Wang Shui; Shen Chenglong

    2012-01-01

    At which height is a prominence inclined to be unstable, or where is the most probable critical height for the prominence destabilization? This question was statistically studied based on 362 solar limb prominences well recognized by Solar Limb Prominence Catcher and Tracker from 2007 April to the end of 2009. We found that there are about 71% disrupted prominences (DPs), among which about 42% of them did not erupt successfully and about 89% of them experienced a sudden destabilization process. After a comprehensive analysis of the DPs, we discovered the following: (1) Most DPs become unstable at a height of 0.06-0.14 R ☉ from the solar surface, and there are two most probable critical heights at which a prominence is very likely to become unstable, the first one is 0.13 R ☉ and the second one is 0.19 R ☉ . (2) An upper limit for the erupting velocity of eruptive prominences (EPs) exists, which decreases following a power law with increasing height and mass; accordingly, the kinetic energy of EPs has an upper limit too, which decreases as the critical height increases. (3) Stable prominences are generally longer and heavier than DPs, and not higher than 0.4 R ☉ . (4) About 62% of the EPs were associated with coronal mass ejections (CMEs); but there is no difference in apparent properties between EPs associated with CMEs and those that are not.

  4. Tic Tac TOE: Effects of Predictability and Importance on Acoustic Prominence in Language Production

    Science.gov (United States)

    Watson, Duane G.; Arnold, Jennifer E.; Tanenhaus, Michael K.

    2008-01-01

    Importance and predictability each have been argued to contribute to acoustic prominence. To investigate whether these factors are independent or two aspects of the same phenomenon, naive participants played a verbal variant of Tic Tac Toe. Both importance and predictability contributed independently to the acoustic prominence of a word, but in…

  5. Heating of an Erupting Prominence Associated with a Solar Coronal Mass Ejection on 2012 January 27

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jin-Yi; Moon, Yong-Jae; Kim, Kap-Sung [Department of Astronomy and Space Science, Kyung Hee University, Yongin-si, Gyeonggi-do, 17104 (Korea, Republic of); Raymond, John C.; Reeves, Katharine K. [Harvard-Smithsonian Center for Astrophysics, Cambridge, MA 02138 (United States)

    2017-07-20

    We investigate the heating of an erupting prominence and loops associated with a coronal mass ejection and X-class flare. The prominence is seen as absorption in EUV at the beginning of its eruption. Later, the prominence changes to emission, which indicates heating of the erupting plasma. We find the densities of the erupting prominence using the absorption properties of hydrogen and helium in different passbands. We estimate the temperatures and densities of the erupting prominence and loops seen as emission features using the differential emission measure method, which uses both EUV and X-ray observations from the Atmospheric Imaging Assembly on board the Solar Dynamics Observatory and the X-ray Telescope on board Hinode . We consider synthetic spectra using both photospheric and coronal abundances in these calculations. We verify the methods for the estimation of temperatures and densities for the erupting plasmas. Then, we estimate the thermal, kinetic, radiative loss, thermal conduction, and heating energies of the erupting prominence and loops. We find that the heating of the erupting prominence and loop occurs strongly at early times in the eruption. This event shows a writhing motion of the erupting prominence, which may indicate a hot flux rope heated by thermal energy release during magnetic reconnection.

  6. 77 FR 3779 - Guidance for Industry on Product Name Placement, Size, and Prominence in Advertising and...

    Science.gov (United States)

    2012-01-25

    ... Advertising and Promotional Labeling; Availability AGENCY: Food and Drug Administration, HHS. ACTION: Notice... entitled ``Product Name Placement, Size, and Prominence in Advertising and Promotional Labeling.'' The..., prominence, and frequency in promotional labeling and advertising for prescription human and animal drugs and...

  7. A high-capacity carbon prepared from renewable chicken feather biopolymer for supercapacitors

    Science.gov (United States)

    Wang, Qiang; Cao, Qi; Wang, Xianyou; Jing, Bo; Kuang, Hao; Zhou, Ling

    2013-03-01

    Micropopous chicken feather carbon (CFC) severing as electrode materials for the first time is prepared via the activation with KOH agent to different extents. The structure and electrochemical properties of CFC materials are characterized with N2 adsorption/desorption measurements, X-ray diffraction (XRD), transmission electron microscope (TEM), cyclic voltammetry (CV), galvanostatic charge/discharge cycling and electrochemical impedance spectroscopy (EIS). The obtained results show that CFC activated by KOH with KOH/CFC weight ratio of 4/1 (CFCA4) possesses the specific surface area of 1839 m2 g-1, average micropore diameter of 1.863 nm, and exhibits the highest initial specific capacitance of 302 F g-1 at current density of 1 A g-1 in 1 M H2SO4, and that even after 5000 cycles, CFCA4 specific capacitance is still as high as 253 F g-1. Furthermore, CFCA4 also delivers specific capacitance of 181 F g-1 at current density of 5 A g-1 and 168 F g-1 at current density of 10 A g-1. Accordingly, the microporous activated carbon material derived from chicken feather provides favorable prospect in electrode materials application in supercapacitors.

  8. All Green Composites from Fully Renewable Biopolymers: Chitosan-Starch Reinforced with Keratin from Feathers

    Directory of Open Access Journals (Sweden)

    Cynthia G. Flores-Hernández

    2014-03-01

    Full Text Available The performance as reinforcement of a fibrillar protein such as feather keratin fiber over a biopolymeric matrix composed of polysaccharides was evaluated in this paper. Three different kinds of keratin reinforcement were used: short and long biofibers and rachis particles. These were added separately at 5, 10, 15 and 20 wt% to the chitosan-starch matrix and the composites were processed by a casting/solvent evaporation method. The morphological characteristics, mechanical and thermal properties of the matrix and composites were studied by scanning electron microscopy, thermogravimetric analysis, differential scanning calorimetry and dynamic mechanical analysis. The thermal results indicated that the addition of keratin enhanced the thermal stability of the composites compared to pure matrix. This was corroborated with dynamic mechanical analysis as the results revealed that the storage modulus of the composites increased with respect to the pure matrix. The morphology, evaluated by scanning electron microscopy, indicated a uniform dispersion of keratin in the chitosan-starch matrix as a result of good compatibility between these biopolymers, also corroborated by FTIR. These results demonstrate that chicken feathers can be useful to obtain novel keratin reinforcements and develop new green composites providing better properties, than the original biopolymer matrix.

  9. Use of Pavo cristatus feather extract for the better management of snakebites: neutralization of inflammatory reactions.

    Science.gov (United States)

    Murari, Satish K; Frey, Felix J; Frey, Brigitte M; Gowda, There V; Vishwanath, Bannikuppe S

    2005-06-03

    In Indian traditional medicine, peacock feather in the form of ash (Bhasma) or water extract are used against snakebite and to treat various problems associated with lungs. This study was aimed to evaluate the water extract of peacock feather (PCF) against the local tissue damage caused due to snakebite. PCF water extract showed inhibition towards phospholipase A2 enzyme activity from snake venom (Naja naja and Vipera russelii), inflammatory fluids (synovial, pleural, ascites) and normal serum in a dose-dependent manner. Hyaluronidase and proteases are other major enzymes in snake venoms responsible for local tissue damage. PCF water extract inhibited hyaluronidase and proteolytic enzyme activities from Vipera russelii, Naja naja and Trimeresurus malabaricus venom. The active principle is a hydrophilic molecule easily extractable in water or polar solvents. PCF water extract gave positive results for the presence of protein and secondary metabolites like carotenoids and steroids. Analysis of metal ions revealed that iron is the major ion (> 20-fold). Other metal ions detected in smaller amount are copper, chromium, zinc and nickel. The least amount of ion detected is gold. Co-injection of PCF water extract with snake venom and inflammatory PLA2 enzymes neutralize the edema inducing activity of all the PLA2 enzymes studied. Since it inhibits hyaluronidase and proteases enzyme activity from snake venom PCF water extract is a powerful neutralizing agent, which has therapeutic application against venom toxicity.

  10. A novel source of biofertilizer from feather biomass for banana cultivation.

    Science.gov (United States)

    Gurav, Ranjit G; Jadhav, Jyoti P

    2013-07-01

    Feather waste is a promising protein biomass available as by-product from poultry processing was found to be rich in peptides, amino acids, and minerals like nitrogen, phosphorus, potassium, calcium, magnesium, iron, manganese, zinc, and copper. Soil and foliar application of these products, besides representing a sustainable solution to the problem of feather disposal, may also represent an effective strategy to tackle the environmental effluence. As a consequence, they were also found to be very attractive in elevating the protein, amino acids, reducing sugar, total chlorophyll, and proline content of plants. On the other side, fertilizing effect enhanced the antioxidant potential of banana fruit which was assessed using 2, 2-diphenyl-1-picrylhydrazyl, ferric reducing/antioxidant power, and N, N-dimethyl-p-phenylendiamine. This was associated with considerably higher antioxidant contents like total phenolics and flavonoids. Therefore, the application of this organic amendment could promote and improve the agro-ecosystem, human health; soil biological activities, and at the same time enhance the production of plant or products rich in bioactive substances.

  11. Sex- and age-related variation in metal content of penguin feathers.

    Science.gov (United States)

    Squadrone, Stefania; Abete, Maria Cesarina; Brizio, Paola; Monaco, Gabriella; Colussi, Silvia; Biolatti, Cristina; Modesto, Paola; Acutis, Pier Luigi; Pessani, Daniela; Favaro, Livio

    2016-03-01

    The presence of xenobiotics, such as metals, in ecosystems is concerning due to their durability and they pose a threat to the health and life of organisms. Moreover, mercury can biomagnify in many marine food chains and, therefore, organisms at higher trophic levels can be adversely impacted. Although feathers have been used extensively as a bio-monitoring tool, only a few studies have addressed the effect of both age and sex on metal accumulation. In this study, the concentrations of trace elements were determined in the feathers of all members of a captive colony of African Penguins (Spheniscus demersus) housed in a zoological facility in Italy. Tests were performed by inductively coupled plasma-mass spectrometry to detect aluminum, arsenic, cadmium, cobalt, chromium, copper, iron, manganese, nickel, lead, selenium, tin, vanadium, and zinc. Mercury was detected by a direct mercury analyzer. Sexing was performed by a molecular approach based on analyzing the chromo-helicase-DNA-binding1 gene, located on the sex chromosomes. Sex- and age-related differences were studied in order to investigate the different patterns of metal bioaccumulation between male and female individuals and between adults and juveniles. Juvenile females had significantly higher arsenic levels than males, while selenium levels increased significantly with age in both sexes. Penguins kept in controlled environments-given that diet and habitat are under strict control-represent a unique opportunity to determine if and how metal bioaccumulation is related to sex and age.

  12. Owls may use faeces and prey feathers to signal current reproduction.

    Directory of Open Access Journals (Sweden)

    Vincenzo Penteriani

    Full Text Available BACKGROUND: Many animals communicate by marking focal elements of their home range with different kinds of materials. Visual signaling has been demonstrated to play a previously unrecognized role in the intraspecific communication of eagle owls (Bubo bubo, in both territorial and parent-offspring contexts. Visual signals may play a role in a variety of circumstances in this crepuscular and nocturnal species. METHODOLOGY/PRINCIPAL FINDINGS: Here, we report that a large amount of extremely visible white faeces and prey feathers appear during the breeding season on posts and plucking sites in proximity to the nest, potentially representing a way for eagle owls to mark their territory. We present descriptive and experimental evidence showing that faeces and prey remains could act as previously unrecognized visual signals in a nocturnal avian predator. This novel signaling behavior could indicate the owls' current reproductive status to potential intruders, such as other territorial owls or non-breeding floaters. Faeces and prey feather markings may also advertise an owl's reproductive status or function in mate-mate communication. CONCLUSIONS/SIGNIFICANCE: We speculate that faeces marks and plucking may represent an overlooked but widespread method for communicating current reproduction to conspecifics. Such marking behavior may be common in birds, and we may now be exploring other questions and mechanisms in territoriality.

  13. Effects of stocking density on growth performance, feather growth, intestinal development, and serum parameters of geese.

    Science.gov (United States)

    Yin, L Y; Wang, Z Y; Yang, H M; Xu, L; Zhang, J; Xing, H

    2017-09-01

    This experiment was conducted to evaluate the effects of stocking density on the growth performance, feather growth, intestinal development, and serum parameters of geese. In total, 336 healthy, 28-day-old, male Yangzhou goslings were randomly allotted to 30 plastic wire-floor pens according to 5 stocking densities (2, 3, 4, 5 and 6 birds/m2). The results showed that with the stocking density increased from 2 birds/m2 to 6 birds/m2, the body weights of geese at 42 d (P density was increased to 6 birds/m2. Serum concentrations of alkaline phosphatase (P = 0.013) and triiodothyronine (P density increased. The serum thyroxine concentration of geese from the 6 birds/m2 group was lower than that of geese from the other groups (P density will adversely influence thyroid function and the developments of the body weight, body size, feathers, and small intestine. Under our experimental conditions, we recommend that the stocking density of geese should be kept to 5 or fewer birds/m2 to avoid the negative effects of high stocking density on geese. © 2017 Poultry Science Association Inc.

  14. Review of psittacine beak and feather disease and its effect on Australian endangered species.

    Science.gov (United States)

    Raidal, S R; Sarker, S; Peters, A

    2015-12-01

    Since it was first described in the early 1980s, psittacine beak and feather disease (PBFD) has become recognised as the dominant viral pathogen of psittacine birds in Australia. Our aim was to evaluate and review the effect of PBFD and its position as a key threatening process to Australian psittacine bird species. We review the origin/evolutionary pathways and potential threat of PBFD to endangered psittacine bird populations and captive-breeding flocks. The most recent beak and feather disease virus (BFDV) phylogenetic analyses indicate that all endangered Australian psittacine bird species are susceptible to, and equally likely to be infected by, BFDV genotypes from a range of host psittacine species. Management of the disease in captive-breeding programs has relied on testing and culling, which has proven costly. The risk of PBFD should be considered very carefully by management teams contemplating the establishment of captive-breeding flocks for endangered species. Alternative disease prevention tools, including vaccination, which are increasingly being used in wildlife health, should be considered more seriously for managing and preventing PBFD in captive flocks of critically endangered species. © 2015 Australian Veterinary Association.

  15. Vertical transmission of feather lice between adult blackbirds Turdus merula and their nestlings: a lousy perspective.

    Science.gov (United States)

    Brooke, M de L

    2010-12-01

    There is limited information about the natural history of the transmission of feather lice (Phthiraptera) from parent birds to their young. This article therefore examines the transmission of 4 species of feather lice from parent blackbirds to their nestlings in an English population, and addresses questions formulated from the perspective of the lice. The lice that disperse onto the several young in the nest were mostly found on the larger chicks, those with higher survival prospects. The lice dispersing to chicks were overwhelmingly nymphs, which cannot be sexed morphologically, and so the prediction that the adult lice dispersing would be disproportionately female, potential founders of a new population, was only supported for the most numerous species, Brueelia merulensis. There was no evidence that louse dispersal to chicks was density dependent and more likely when the parents were more heavily infested. Finally, I predicted that lice might aggregate on female blackbirds, which undertake more brooding, to increase their chance of transmission to nestlings. For 1 louse species, B. merulensis, prevalence, but not louse intensity, was higher on female than male blackbirds. For 2 other louse species, Philopterus turdi and Menacanthus eurysternus, no differences between male and female blackbirds were detected.

  16. Development of the skeleton and feathers of dusky parrots (Pionus fuscus) in relation to their behaviour.

    Science.gov (United States)

    Harcourt-Brown, N

    2004-01-10

    A clutch of five dusky parrots (Pionus fuscus) was observed from hatching to fully grown. They were examined radiographically from 16 to 45 days of age, a few days before the cessation of bone growth, and the development of their feathers and their behaviour were also studied. It was observed that when growing birds were removed from the nest and placed singly on a flat surface they would stand up and walk about until restrained; normally these birds would move very little and lie in an intertwined huddle that supported their relatively weak growing skeletons. At 50 days old they would climb to the nest entrance, retreating if scared. From day 51 the parrots flapped their wings vigorously inside the nest box, and they emerged at 53 days old when nearly all their large feathers had finished growing. These findings may help to explain the high rate of juvenile osteodystrophy in hand-reared parrots; premature exercise could lead to pathological deformity of the long bones, especially the major weight-bearing bone, the tibiotarsus.

  17. Owls may use faeces and prey feathers to signal current reproduction.

    Science.gov (United States)

    Penteriani, Vincenzo; Delgado, Maria del Mar

    2008-08-20

    Many animals communicate by marking focal elements of their home range with different kinds of materials. Visual signaling has been demonstrated to play a previously unrecognized role in the intraspecific communication of eagle owls (Bubo bubo), in both territorial and parent-offspring contexts. Visual signals may play a role in a variety of circumstances in this crepuscular and nocturnal species. Here, we report that a large amount of extremely visible white faeces and prey feathers appear during the breeding season on posts and plucking sites in proximity to the nest, potentially representing a way for eagle owls to mark their territory. We present descriptive and experimental evidence showing that faeces and prey remains could act as previously unrecognized visual signals in a nocturnal avian predator. This novel signaling behavior could indicate the owls' current reproductive status to potential intruders, such as other territorial owls or non-breeding floaters. Faeces and prey feather markings may also advertise an owl's reproductive status or function in mate-mate communication. We speculate that faeces marks and plucking may represent an overlooked but widespread method for communicating current reproduction to conspecifics. Such marking behavior may be common in birds, and we may now be exploring other questions and mechanisms in territoriality.

  18. BMP2 and BMP7 play antagonistic roles in feather induction

    Science.gov (United States)

    Michon, Frédéric; Forest, Loïc; Collomb, Elodie; Demongeot, Jacques; Dhouailly, Danielle

    2008-01-01

    Summary During embryonic development, feathers first appear as primordia consisting of an epidermal placode associated with a dermal condensation. In most previous studies, the BMPs have been proposed to function as inhibitors of the formation of cutaneous appendages. We showed that the function of BMPs is quite nuanced: BMP-2 and BMP-7, which are expressed in both skin components, act antagonistically and yet are both involved in the dermal condensations formation. BMP-7, the first to be expressed, is implicated in chemotaxis which leads to cell recruitment to the condensation, whereas BMP-2, which is expressed later, leads to an arrest of cell migration, likely via its modulation of EIIIA Fibronectin domain and α4-Integrin expression. We also propose a mathematical model, a reaction-diffusion system, based on cell proliferation, chemotaxis and the timing of BMP-2 and BMP-7 expression, which simulates the endogenous situation and reproduces the negative effects of excess BMP-2 or BMP-7 on feather patterning. PMID:18635609

  19. Physics of Solar Prominences: I-Spectral Diagnostics and Non-LTE Modelling

    Science.gov (United States)

    Labrosse, N.; Heinzel, P.; Vial, J.-C,; Kucera, T.; Parenti, S.; Gunar, S.; Schmieder, B.; Kilper, G.

    2010-01-01

    This review paper outlines background information and covers recent advances made via the analysis of spectra and images of prominence plasma and the increased sophistication of non-LTE (i.e. when there is a departure from Local Thermodynamic Equilibrium) radiative transfer models. We first describe the spectral inversion techniques that have been used to infer the plasma parameters important for the general properties of the prominence plasma in both its cool core and the hotter prominence-corona transition region. We also review studies devoted to the observation of bulk motions of the prominence plasma and to the determination of prominence mass. However, a simple inversion of spectroscopic data usually fails when the lines become optically thick at certain wavelengths. Therefore, complex

  20. Fabrication of micro-prominences on PTFE surface using proton beam writing

    Energy Technology Data Exchange (ETDEWEB)

    Kitamura, Akane, E-mail: ogawa.akane@jaea.go.jp [Department of Advanced Radiation Technology, Takasaki Advanced Radiation Research Institute, Japan Atomic Energy Agency, 1233 Watanuki-Machi, Takasaki, Gunma 370-1292 (Japan); Satoh, Takahiro; Koka, Masashi [Department of Advanced Radiation Technology, Takasaki Advanced Radiation Research Institute, Japan Atomic Energy Agency, 1233 Watanuki-Machi, Takasaki, Gunma 370-1292 (Japan); Kobayashi, Tomohiro [Advanced Science Institute, RIKEN, 2-1 Hirosawa, Wako-shi, Saitama 350-0198 (Japan); Kamiya, Tomihiro [Department of Advanced Radiation Technology, Takasaki Advanced Radiation Research Institute, Japan Atomic Energy Agency, 1233 Watanuki-Machi, Takasaki, Gunma 370-1292 (Japan)

    2013-07-01

    Polytetrafluoroethylene (PTFE) is a typical fluoropolymer and it has several desirable technological properties such as electrical insulation, solid lubrication etc. However, the conventional microstructuring methods have not been well applied to PTFE due to its chemical inertness. Some effective micromachining using synchrotron radiation or ion beam irradiation has been reported. In this study, we create micro-prominences by raising the original surface using proton beam writing (PBW) without chemical etching. A conical prominence was formed by spiral drawing from the center with a 3 MeV proton beam. The body was porous, and the bulk PTFE below the prominence changed to fragmented structures. With decreasing writing speed, the prominence became taller but the height peaked. The prominence gradually reduced in size after the speed reached the optimum value. We expect that these porous projections with high aspect ratio will be versatile in medical fields and microelectromechanical systems (MEMS) technology.

  1. Modeling of prominence threads in magnetic fields: Levitation by incompressible MHD waves

    Science.gov (United States)

    Pécseli, Hans; Engvold, OddbjØrn

    2000-05-01

    The nature of thin, highly inclined threads observed in quiescent prominences has puzzled solar physicists for a long time. When assuming that the threads represent truly inclined magnetic fields, the supporting mechanism of prominence plasma against gravity has remained an open issue. This paper examines the levitation of prominence plasma exerted by weakly damped MHD waves in nearly vertical magnetic flux tubes. It is shown that the wave damping, and resulting `radiation pressure', caused predominantly by ion-neutral collisions in the `cold' prominence plasma, may balance the acceleration of gravity provided the oscillation frequency is ω~ 2 rad s^-1 (f~0.5 Hz). Such short wave periods may be the result of small-scale magnetic reconnections in the highly fragmentary magnetic field of quiescent prominences. In the proposed model, the wave induced levitation acts predominantly on plasma - neutral gas mixtures.

  2. Feather retention force in broiler carcasses slaughtered and held up to 8 hours postmortem prior to scalding

    Science.gov (United States)

    One factor that could impact the feasibility of commercial on-farm slaughter of broilers is the time delay from on-farm slaughter to scalding and defeathering in the commercial plant that could be 4 h or more. This experiment evaluated feather retention force (FRF) in broilers that were slaughtered ...

  3. New feather mites of the subfamily Pterodectinae (Acari: Astigmata: Proctophyllodidae) from passerines (Aves: Passeriformes) in Mato Grosso do Sul, Brazil

    Czech Academy of Sciences Publication Activity Database

    Mironov, S. V.; Literák, I.; Čapek, Miroslav

    2008-01-01

    Roč. 1947, - (2008), s. 1-38 ISSN 1175-5326 Institutional research plan: CEZ:AV0Z60930519 Keywords : Acari * Astigmata * feather mites * systematics * Brazil * Proctophyllodidae * Aves * Passeriformes Subject RIV: EG - Zoology Impact factor: 0.740, year: 2008 http://www.mapress.com/zootaxa/2008/f/zt01947p038.pdf

  4. A new helical crossed-fibre structure of β-keratin in flight feathers and its biomechanical implications.

    Science.gov (United States)

    Lingham-Soliar, Theagarten; Murugan, Nelisha

    2013-01-01

    The feather aerofoil is unequalled in nature. It is comprised of a central rachis, serial paired branches or barbs, from which arise further branches, the barbules. Barbs and barbules arise from the significantly thinner lateral walls (the epicortex) of the rachis and barbs respectively, as opposed to the thicker dorsal and ventral walls (the cortex). We hypothesized a microstructural design of the epicortex that would resist the vertical or shearing stresses. The microstructures of the cortex and epicortex of the rachis and barbs were investigated in several bird species by microbe-assisted selective disassembly and conventional methods via scanning electron microscopy. We report, preeminent of the finds, a novel system of crossed fibres (ranging from ∼100-800 nm in diameter), oppositely oriented in alternate layers of the epicortex in the rachis and barbs. It represents the first cross-fibre microstructure, not only for the feather but in keratin per se. The cortex of the barbs is comprised of syncitial barbule cells, definitive structural units shown in the rachidial cortex in a related study. The structural connection between the cortex of the rachis and barbs appears uninterrupted. A new model on feather microstructure incorporating the findings here and in the related study is presented. The helical fibre system found in the integument of a diverse range of invertebrates and vertebrates has been implicated in profound functional strategies, perhaps none more so potentially than in the aerofoil microstructure of the feather here, which is central to one of the marvels of nature, bird flight.

  5. Mercury concentrations in breast feathers of three upper trophic level marine predators from the western Aleutian Islands, Alaska.

    Science.gov (United States)

    Kaler, Robb S A; Kenney, Leah A; Bond, Alexander L; Eagles-Smith, Collin A

    2014-05-15

    Mercury (Hg) is a toxic element distributed globally through atmospheric transport. Agattu Island, located in the western Aleutian Islands, Alaska, has no history of point-sources of Hg contamination. We provide baseline levels of total mercury (THg) concentrations in breast feathers of three birds that breed on the island. Geometric mean THg concentrations in feathers of fork-tailed storm-petrels (Oceanodroma furcata; 6703 ± 1635, ng/g fresh weight [fw]) were higher than all other species, including snowy owl (Bubo scandiacus; 2105 ± 1631, ng/g fw), a raptor with a diet composed largely of storm-petrels at Agattu Island. There were no significant differences in mean THg concentrations of breast feathers among adult Kittlitz's murrelet (Brachyramphus brevirostris; 1658 ± 1276, ng/g fw) and chicks (1475 ± 671, ng/g fw) and snowy owls. The observed THg concentrations in fork-tailed storm-petrel feathers emphasizes the need for further study of Hg pollution in the western Aleutian Islands. Published by Elsevier Ltd.

  6. Mercury concentrations in breast feathers of three upper trophic level marine predators from the western Aleutian Islands, Alaska

    Science.gov (United States)

    Kaler, Robb S.A.; Kenney, Leah A.; Bond, Alexander L.; Eagles-Smith, Collin A.

    2014-01-01

    Mercury (Hg) is a toxic element distributed globally through atmospheric transport. Agattu Island, located in the western Aleutian Islands, Alaska, has no history of point-sources of Hg contamination. We provide baseline levels of total mercury (THg) concentrations in breast feathers of three birds that breed on the island. Geometric mean THg concentrations in feathers of fork-tailed storm-petrels (Oceanodroma furcata; 6703 ± 1635, ng/g fresh weight [fw]) were higher than all other species, including snowy owl (Bubo scandiacus; 2105 ± 1631, ng/g fw), a raptor with a diet composed largely of storm-petrels at Agattu Island. There were no significant differences in mean THg concentrations of breast feathers among adult Kittlitz’s murrelet (Brachyramphus brevirostris; 1658 ± 1276, ng/g fw) and chicks (1475 ± 671, ng/g fw) and snowy owls. The observed THg concentrations in fork-tailed storm-petrel feathers emphasizes the need for further study of Hg pollution in the western Aleutian Islands.

  7. Behavioral changes and feathering score in heat stressed broiler chickens fed diets containing different levels of propolis

    Science.gov (United States)

    This experiment was conducted to evaluate the effects of dietary supplementation of green Brazilian propolis on behavioral patterns and feather condition of heat stressed broiler chickens. Five hundred and four (504) male Ross 708 broiler chicks at 15-day old were randomly allotted to six dietary tr...

  8. Mixed housing of different genetic lines of laying hens negatively affects feather pecking and fear related behaviour

    NARCIS (Netherlands)

    Uitdehaag, K.A.; Rodenburg, T.B.; Bolhuis, J.E.; Decuypere, E.; Komen, J.

    2009-01-01

    Adult laying hens from Rhode Island Red (RIR) origin both express lower levels of feather pecking and lower fear responses towards a novel object than laying hens from White Leghorn (WL) origin. The present study investigated whether mixed housing of RIR and WL laying hens would affect their

  9. Concentrations of metals in blood and feathers of nestling ospreys (Pandion haliaetus) in Chesapeake and Delaware Bays

    Science.gov (United States)

    Rattner, B.A.; Golden, N.H.; Toschik, P.C.; McGowan, P.C.; Custer, T.W.

    2008-01-01

    In 2000, 2001, and 2002, blood and feather samples were collected from 40-45-day-old nestling ospreys (Pandion haliaetus) from Chesapeake Bay and Delaware Bay and River. Concentrations of 18 metals, metalloids, and other elements were determined in these samples by inductively coupled plasma-mass spectroscopy, and Hg concentrations were measured by cold vapor atomic absorption spectroscopy. When compared to concurrent reference areas (South, West, and Rhode Rivers), mean As and Hg concentrations in blood were greater (p nestlings from the highly industrialized Elizabeth River compared to the rural reference area. When compared to the concurrent reference area, mean Al, Ba, Hg, Mn, and Pb concentrations in feathers were substantially greater (p nestlings from northern Delaware Bay and River had greater concentrations (p nestling feathers from Delaware were frequently greater than in the Chesapeake. The present findings and those of related reproductive studies suggest that concentrations of several heavy metals (e.g., Cd, Hg, Pb) in nestling blood and feathers from Chesapeake and Delaware Bays were below toxicity thresholds and do not seem to be affecting chick survival during the nestling period.

  10. Laying hens in aviaries with different litter substrates: Behavior across the flock cycle and feather lipid content.

    Science.gov (United States)

    Campbell, D L M; Ali, A B A; Karcher, D M; Siegford, J M

    2017-09-01

    The tiered aviary for laying hens includes a floor litter area to promote foraging and dust bathing. Data are needed on hens' use of different litter substrates and effectiveness of substrates in removing excess feather lipids to ensure a suitable litter area. Bovans White hens were housed in commercial-style aviaries with access to one of 3 litter substrates (wood shavings, straw, or plastic turf mats-AstroTurf®, n = 4 aviary pens per substrate, 144 cage-reared hens populated per pen). Litter areas were videoed across 2 d each at 4 ages: immediately following first aviary opening (25 wk), then at 28, 50, and 68 weeks. Observations of hens throughout the d included percentages of all hens in each pen on the litter area, foraging and transitioning between the tiered enclosure and litter area. Percentages of hens dust bathing were observed from 11:00 to 15:00. Breast and back feather samples from 7 birds per pen at 28, 50, and 68 wk were analyzed for lipid content. Overall, fewer hens simultaneously accessed the AstroTurf® (P Feather lipid differences among litter substrates (P feathers (P nest boxes, but straw and shavings are more ideal litter substrates. Further study should investigate alternative substrates or regular substrate addition to encourage more foraging and dust bathing. © The Author 2017. Published by Oxford University Press on behalf of Poultry Science Association.

  11. The GroupHouseNet COST Action: exploiting European synergy to reduce feather pecking in laying hens

    DEFF Research Database (Denmark)

    Rodenburg, T.B.; Berk, J; Dimitrov, I.

    2017-01-01

    The COST Action GroupHouseNet focuses on the reduction of damaging behaviour in laying hens and pigs, benefiting from the fact that there are many similarities in causation and solutions for feather pecking and tail biting. The research in the network focuses on three main topics, addressed by th...

  12. Linking hydrogen (δ2H isotopes in feathers and precipitation: sources of variance and consequences for assignment to isoscapes.

    Directory of Open Access Journals (Sweden)

    Keith A Hobson

    Full Text Available Tracking small migrant organisms worldwide has been hampered by technological and recovery limitations and sampling bias inherent in exogenous markers. Naturally occurring stable isotopes of H (δ(2H in feathers provide an alternative intrinsic marker of animal origin due to the predictable spatial linkage to underlying hydrologically driven flow of H isotopes into foodwebs. This approach can assess the likelihood that a migrant animal originated from a given location(s within a continent but requires a robust algorithm linking H isotopes in tissues of interest to an appropriate hydrological isotopic spatio-temporal pattern, such as weighted-annual rainfall. However, a number of factors contribute to or alter expected isotopic patterns in animals. We present results of an extensive investigation into taxonomic and environmental factors influencing feather δ(2H patterns across North America.Stable isotope data were measured from 544 feathers from 40 species and 140 known locations. For δ(2H, the most parsimonious model explaining 83% of the isotopic variance was found with amount-weighted growing-season precipitation δ(2H, foraging substrate and migratory strategy.This extensive H isotopic analysis of known-origin feathers of songbirds in North America and elsewhere reconfirmed the strong coupling between tissue δ(2H and global hydrologic δ(2H patterns, and accounting for variance associated with foraging substrate and migratory strategy, can be used in conservation and research for the purpose of assigning birds and other species to their approximate origin.

  13. Hydrogels from feather keratin show higher viscoelastic properties and cell proliferation than those from hair and wool keratins.

    Science.gov (United States)

    Esparza, Yussef; Bandara, Nandika; Ullah, Aman; Wu, Jianping

    2018-09-01

    Hydrogel prepared from keratin shows potential applications in tissue engineering. However, the importance of the keratin sources has not been considered. The objectives of this study were to characterize and compare the rheological (storage modulus), physical (porosity, pore size, swelling capacity, and water contact angle) and in vitro cell compatibility of hydrogel scaffolds prepared from various keratin sources. Keratins were characterized by means of their molecular weight, amino acid composition, thermal and conformational properties. Hydrogels from chicken feather keratins demonstrated substantially higher storage modulus (G') than hair and wool keratin hydrogels. However, higher swelling capacity (>3000%) was determined in hair and wool over feather keratin (1500%) hydrogels. Our results suggest that small molecular weight and β-sheet conformation of feather keratin (~10 kDa) facilitated the self-assembly of rigid hydrogels through disulfide bond re-oxidation. Whereas, high molecular weight (10-75 kDa) stretchable α-helix conformation in hair and wool keratins resulted in weaker hydrogels. The cell cultures using fibroblasts showed the highest proliferation rate on chicken feather keratin hydrogel scaffolds. After 15 days of culture, partial breakdown of keratin fibers was observed. Results indicate that stiffer avian keratins can be used to fabricate more mechanically robust biomaterials than mammalian keratins. Copyright © 2018 Elsevier B.V. All rights reserved.

  14. Effects of ambient temperature, feather cover, and housing system on energy partitioning and performance in laying hens

    NARCIS (Netherlands)

    Krimpen, van M.M.; Binnendijk, G.P.; Anker, van den I.; Heetkamp, M.J.W.; Kwakkel, R.P.; Brand, van den H.

    2014-01-01

    Environmental factors, such as ambient temperature (T), feather cover (FC), and housing system (HS), probably affect energy requirements of laying hens. Using a 3 × 2 × 2 factorial arrangement, interaction effects of T (11, 16, and 21°C), FC (100 and 50%), and HS (cage and floor housing) on energy

  15. Using nestling feathers to assess spatial and temporal concentrations of mercury in bald eagles at Voyageurs National Park, Minnesota, USA

    Science.gov (United States)

    H. T. Pittman; W. W. Bowerman; L. H. Grim; Teryl Grubb; W. C. Bridges

    2011-01-01

    Bald eagles (Haliaeetus leucocephalus) have been utilized as a biosentinel of aquatic ecosystem health in the Great Lakes Region since the early 1960s. Bald eagle populations have been monitored at Voyageurs National Park (VNP), Minnesota, since 1973. For the past 20 years, researchers have collected feathers from nestling bald eagles to assess their dietary exposure...

  16. Determination of Oxytetracycline and 4-Epi-Oxytetracycline Residues in Feathers and Edible Tissues of Broiler Chickens Using Liquid Chromatography Coupled with Tandem Mass Spectrometry.

    Science.gov (United States)

    Cornejo, Javiera; Pokrant, Ekaterina; Krogh, Magdalena; Briceño, Cristóbal; Hidalgo, Héctor; Maddaleno, Aldo; Araya-Jordán, Carolina; Martín, Betty San

    2017-04-01

    Antibiotics have been widely used in poultry production for the treatment of bacterial diseases. However, drug residues can remain in products derived from animals after the cessation of the drug therapies. Feathers, in particular, have shown an affinity for antibiotics such as tetracycline, suggesting the persistence of these drugs in nonedible tissue. After the birds are slaughtered, feathers are ground into feather meals, which are used as organic fertilizer or an ingredient in animal diets, thereby entering into the food chain and becoming a potential risk for public health. To evaluate the depletion of oxytetracycline (OTC) and its metabolite 4-epi-oxytetracycline (4-epi-OTC) in the muscles, liver, and feathers, 64 broiler chickens, bred under controlled conditions, were treated orally with a commercial formulation of 10% OTC for 7 days. The analytes were quantified using liquid chromatography-tandem mass spectrometry. OTC and 4-epi-OTC were found in the feathers for 46 days, whereas they were found in the muscle and liver for only 12 and 6 days, respectively. These results prove that the analytes remain in feathers in higher concentrations than they do in edible tissues after treatment with tetracyclines. Thus, feather meals represent a potential source of antimicrobial residue contamination in the food chain.

  17. TORNADO-LIKE EVOLUTION OF A KINK-UNSTABLE SOLAR PROMINENCE

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Wensi; Liu, Rui; Wang, Yuming, E-mail: rliu@ustc.edu.cn [CAS Key Laboratory of Geospace Environment, Department of Geophysics and Planetary Sciences, University of Science and Technology of China, Hefei 230026 (China)

    2017-01-01

    We report on the tornado-like evolution of a quiescent prominence on 2014 November 1. The eastern section of the prominence first rose slowly, transforming into an arch-shaped structure as high as ∼150 Mm above the limb; the arch then writhed moderately in a left-handed sense, while the original dark prominence material emitted in the Fe ix 171 Å passband, and a braided structure appeared at the eastern edge of the warped arch. The unraveling of the braided structure was associated with a transient brightening in the EUV and apparently contributed to the formation of a curtain-like structure (CLS). The CLS consisted of myriad thread-like loops rotating counterclockwise about the vertical if viewed from above. Heated prominence material was observed to slide along these loops and land outside the filament channel. The tornado eventually disintegrated and the remaining material flew along a left-handed helical path constituting approximately a full turn, as corroborated through stereoscopic reconstruction, into the cavity of the stable, western section of the prominence. We suggest that the tornado-like evolution of the prominence was governed by the helical kink instability, and that the CLS formed through magnetic reconnections between the prominence field and the overlying coronal field.

  18. Prominence-corona interface compared with the chromosphere-corona transition region

    Energy Technology Data Exchange (ETDEWEB)

    Orrall, F Q; Schmahl, E J [Harvard Coll. Observatory, Cambridge, Mass. (USA)

    1976-11-01

    The intensities of 52 EUV emission lines from each of 9 hedgerow prominences observed at the limb with the Harvard experiment on ATM-Skylab have been compared with intensities from the interior of network cells at the center of the disk, in order to compare the prominence-corona (P-C) interface with the chromosphere-corona (C-C) transition region. The intensity ratio Isub(cell)/Isub(prominence) for each line varies systematically (in all of the prominences observed), with the temperature of formation of the line as approximately Tsup(-0.6). The density sensitive C III (formed at T approximately 9x10/sup 4/ K) line ratio Isub(lambda1175)/Isub(lambda977) implies an average density 1.3x10/sup 9/ electrons cm/sup -3/ in the P-C interface and approximately 4 times this value in the C-C transition of the cells. The total optical thickness at the head of the Lyman continuum is < approximately 10 in most of the prominences studied; in two of the prominences, however, the possibility that tau/sub 0/ is large cannot be rejected. Methods of analysis of these EUV data are developed assuming both a resolved and an unresolved internal prominence structure. Although the systematic differences between the P-C interface and the C-C transition are stressed, the similarities are probably more remarkable and may be a result of fine structure in the C-C transition.

  19. Lead, mercury, cadmium, chromium, and arsenic levels in eggs, feathers, and tissues of Canada geese of the New Jersey Meadowlands

    International Nuclear Information System (INIS)

    Tsipoura, Nellie; Burger, Joanna; Newhouse, Michael; Jeitner, Christian; Gochfeld, Michael; Mizrahi, David

    2011-01-01

    The New Jersey Meadowlands are located within the heavily urbanized New York/New Jersey Harbor Estuary and have been subject to contamination due to effluent and runoff from industry, traffic, and homes along the Hackensack River and nearby waterways. These extensive wetlands, though heavily impacted by development and pollution, support a wide array of bird and other wildlife species. Persistent contaminants may pose threats to birds in these habitats, affecting reproduction, egg hatchability, nestling survival, and neurobehavioral development. Metals of concern in the Meadowlands include arsenic, cadmium, chromium, lead, and mercury. These metals were analyzed in eggs, feathers, muscle, and liver of Canada geese (Branta canadensis) breeding in four wetland sites. We sampled geese collected during control culling (n=26) and collected eggs from goose nests (n=34). Levels of arsenic were below the minimum quantification level (MQL) in most samples, and cadmium and mercury were low in all tissues sampled. Chromium levels were high in feather samples. Mercury levels in eggs of Canada geese, an almost exclusively herbivorous species, were lower (mean ±SE 4.29±0.30 μg/g wet weight) than in eggs of omnivorous mallards (Anas platyrhynchos), and insectivorous red-winged blackbirds (Agelaius phoeniceus) and marsh wrens (Cistothorus palustris) from the Meadowlands, consistent with trophic level differences. However, lead levels were higher in the goose eggs (161±36.7 ng/g) than in the other species. Geese also had higher levels of lead in feathers (1910±386 ng/g) than those seen in Meadowlands passerines. By contrast, muscle and liver lead levels were within the range reported in waterfowl elsewhere, possibly a reflection of metal sequestration in eggs and feathers. Elevated lead levels may be the result of sediment ingestion or ingestion of lead shot and sinkers. Finally, lead levels in goose liver (249±44.7 ng/g) and eggs (161±36.7 ng/g) may pose a risk if consumed

  20. Pallid bands in feathers and associated stable isotope signatures reveal effects of severe weather stressors on fledgling sparrows.

    Science.gov (United States)

    Ross, Jeremy D; Kelly, Jeffrey F; Bridge, Eli S; Engel, Michael H; Reinking, Dan L; Boyle, W Alice

    2015-01-01

    In August 2013, we observed a high incidence (44%) of synchronous bands of reduced melanin (a type of fault bar we have termed "pallid bands") across the rectrices of juvenile Grasshopper Sparrows (Ammodrammus savannarum) captured near El Reno, Oklahoma. Earlier that year, on May 31, the site was struck by a severe storm which rained hailstones exceeding 5.5 cm diameter and spawned an historic 4.2 km-wide tornado stressor had induced the pallid bands. An assessment of Grasshopper Sparrow nesting phenology indicated that a large number of nestlings were likely growing tail feathers when the storm hit. The pallid bands were restricted to the distal half of feathers and their widths significantly increased as a function of distance from the tip (i.e., age at formation). We predicted that if stress had caused these pallid bands, then a spike in circulating δ (15)N originating from tissue catabolism during the stress response would have been incorporated into the developing feather. From 18 juveniles captured at the site in August we measured δ (15)N and δ (13)C stable isotope ratios within four to five 0.25-0.40 mg feather sections taken from the distal end of a tail feather; the pallid band, if present, was contained within only one section. After accounting for individual and across-section variation, we found support for our prediction that feather sections containing or located immediately proximal to pallid bands (i.e., the pallid band region) would show significantly higher δ (15)N than sections outside this region. In contrast, the feathers of juveniles with pallid bands compared to normal appearing juveniles showed significantly lower δ (15)N. A likely explanation is that the latter individuals hatched after the May 31 storm and had consumed a trophically-shifted diet relative to juveniles with pallid bands. Considering this, the juveniles of normal appearance were significantly less abundant within our sample relative to expectations from past cohorts (z

  1. Pallid bands in feathers and associated stable isotope signatures reveal effects of severe weather stressors on fledgling sparrows

    Directory of Open Access Journals (Sweden)

    Jeremy D. Ross

    2015-03-01

    Full Text Available In August 2013, we observed a high incidence (44% of synchronous bands of reduced melanin (a type of fault bar we have termed “pallid bands” across the rectrices of juvenile Grasshopper Sparrows (Ammodrammus savannarum captured near El Reno, Oklahoma. Earlier that year, on May 31, the site was struck by a severe storm which rained hailstones exceeding 5.5 cm diameter and spawned an historic 4.2 km-wide tornado <8 km to the south of the site. We hypothesized that this stressor had induced the pallid bands. An assessment of Grasshopper Sparrow nesting phenology indicated that a large number of nestlings were likely growing tail feathers when the storm hit. The pallid bands were restricted to the distal half of feathers and their widths significantly increased as a function of distance from the tip (i.e., age at formation. We predicted that if stress had caused these pallid bands, then a spike in circulating δ15N originating from tissue catabolism during the stress response would have been incorporated into the developing feather. From 18 juveniles captured at the site in August we measured δ15N and δ13C stable isotope ratios within four to five 0.25–0.40 mg feather sections taken from the distal end of a tail feather; the pallid band, if present, was contained within only one section. After accounting for individual and across-section variation, we found support for our prediction that feather sections containing or located immediately proximal to pallid bands (i.e., the pallid band region would show significantly higher δ15N than sections outside this region. In contrast, the feathers of juveniles with pallid bands compared to normal appearing juveniles showed significantly lower δ15N. A likely explanation is that the latter individuals hatched after the May 31 storm and had consumed a trophically-shifted diet relative to juveniles with pallid bands. Considering this, the juveniles of normal appearance were significantly less abundant

  2. Motions in Prominence Barbs as observed by Hinode/SOT and IRIS

    Science.gov (United States)

    Kucera, Therese A.; Ofman, Leon; Tarbell, Theodore D.

    2016-05-01

    We discuss observations of prominence barb dynamics as observed by Hinode/SOT and IRIS. Prominence barbs extend outwards to the side of the main prominence spine and downwards towards the chromosphere. Their properties, including the structure of their magnetic field and the nature of the motions observed in them are a subject of current debate. We use a combination of high cadence, high resolution imaging, H-alpha Doppler, and Mg II line profile data to analyze and understand waves and flows in barbs and discuss their ramifications in terms of a model of the barb magnetic field as collection of dipped field lines.

  3. Metal and Isotope Analysis of Bird Feathers in a Contaminated Estuary Reveals Bioaccumulation, Biomagnification, and Potential Toxic Effects.

    Science.gov (United States)

    Einoder, L D; MacLeod, C K; Coughanowr, C

    2018-07-01

    The Derwent estuary, in south east Tasmania, is highly contaminated with heavy metals, mainly due to past industrial pollution. This study sought to determine the extent of contamination, bioaccumulation, and biomagnification in the resident bird community and therefore to infer the potential for adverse effects in birds. Thirteen metals were measured from breast feathers (n = 51 individuals) of eight sympatric species of aquatic bird. Stable carbon (δ 13 C) and nitrogen (δ 15 N) isotopes were used to identify dietary sources of contaminants, trophic level, and potential biomagnification through food chains. Generalised linear models revealed that metal burdens were often poorly correlated with δ 13 C, indicating their uptake from a range of freshwater, brackish, and marine carbon sources-not surprising due to widespread contamination across the tidal estuary. Feather mercury increased significantly with trophic level (inferred from δ 15 N). White-bellied Sea-eagle Haliaeetus leucogaster samples contained 240 times more mercury than feral Goose Anser cygnoides. Feather arsenic and copper concentrations were significantly higher in birds feeding lower in the food chain. For several piscivorous species, both chick and adults were sampled revealing significantly higher feather mercury, zinc, and selenium in adults. Feathers from birds found dead along the banks of the estuary had significantly higher lead loads than from live birds, and numerous individuals had levels of mercury, zinc, and lead above toxic thresholds reported in other studies. These results highlight the need to include biota from higher trophic levels in contaminant monitoring programs to understand fully the fate and broader implications of contaminants in the environment.

  4. Seabird feathers as monitors of the levels and persistence of heavy metal pollution after the Prestige oil spill

    International Nuclear Information System (INIS)

    Moreno, Rocio; Jover, Lluis; Diez, Carmen; Sanpera, Carola

    2011-01-01

    We measured heavy metal concentrations in yellow-legged gulls (n = 196) and European shags (n = 189) in order to assess the temporal pattern of contaminant exposure following the Prestige oil spill in November 2002. We analysed Pb, Cu, Zn, Cr, Ni and V levels in chick feathers sampled at four colonies during seven post-spill years (2003-2009), and compared results with pre-spill levels obtained from feathers of juvenile shag corpses (grown in spring/summer 2002). Following the Prestige wreck, Cu (4.3-10 μg g -1 ) and Pb concentrations (1.0-1.4 μg g -1 ) were, respectively, between two and five times higher than pre-spill levels (1.5-3.6 and 0.1-0.4 μg g -1 ), but returned to previous background concentrations after three years. Our study highlights the suitability of chick feathers of seabirds for assessing the impact of oil spills on heavy metal contamination, and provides the best evidence to date on the persistence of oil pollution after the Prestige incident. - Highlights: → Seabirds as sentinel species of levels and persistence of heavy metal pollution after oil spills. → Pb, Cu, Zn, Cr, Ni, V in chick feathers of Phalacrocorax aristotelis and Larus michahellis. → Chronic oil pollution in the marine food web for at least three years after the Prestige oil spill. - Monitoring heavy metal in seabird feathers indicated chronic oil pollution in the marine food web for at least three years after the Prestige oil spill.

  5. Element patterns in feathers of nestling Black-Crowned Night-Herons, Nycticorax nycticorax L., from four colonies in Delaware, Maryland, and Minnesota

    Science.gov (United States)

    Custer, Thomas W.; Golden, Nancy H.; Rattner, Barnett A.

    2008-01-01

    The pattern of elements in nestling black-crowned night-heron feathers from a rural Minnesota colony differed from colonies in industrialized regions of Maryland and Delaware. Except for chromium, however, the differences did not reflect the elements associated with waters and sediments of the Maryland and Delaware colonies. Therefore, elements in water and sediment do not necessarily bioaccumulate in night-heron feathers in relation to potential exposure. Although trace element patterns in feathers indicated differences among geographical locations, they did not separate all locations well and their usefulness as an indicator of natal colony location may be limited.

  6. Development of a prognostic tool for the occurrence of feather pecking and cannibalism in laying hens.

    Science.gov (United States)

    Kaesberg, A-K U; Louton, H; Erhard, M; Schmidt, P; Zepp, M; Helmer, F; Schwarzer, A

    2018-03-01

    In July 2015, a German voluntary decree stipulated that the keeping of beak-trimmed laying hens after the 1st of January 2017 will no longer be permitted. Simultaneously, the present project was initiated to validate a newly developed prognostic tool for laying hen farmers to forecast, at the beginning of a laying period, the probability of future problems with feather pecking and cannibalism in their flock. For this purpose, we used a computer-based prognostic tool in form of a questionnaire that was easy and quick to complete and facilitated comparisons of different flocks. It contained various possible risk factors that were classified into 3 score categories (1 = "no need for action," 2 = "intermediate need for action," 3 = "instant need for action"). For the validation of this tool, 43 flocks of 41 farms were examined twice, at the beginning of the laying period (around the 20th wk of life) and around the 67th wk of life. At both visits, the designated investigators filled out the questionnaire and assessed the plumage condition and the skin lesions (as indicators of occurrence of feather pecking and cannibalism) of 50 laying hens of each flock. The average prognostic score of the first visit was compared with the existence of feather pecking and cannibalism in each flock at the end of the laying period. The results showed that the prognostic score was negatively correlated with the plumage score (r = -0.32; 95% confidence interval [CI]: [-0.56; -0.02]) and positively correlated with the skin lesion score (r = 0.38; 95% CI: [0.09; 0.61]). These relationships demonstrate that a better prognostic score was associated with a better plumage and skin lesion score. After performing a principal component analysis on the single scores, we found that only 6 components are sufficient to obtain highly sensitive and specific prognostic results. Thus, the data of this analysis should be used for creating applicable software for use on laying hen farms.

  7. MULTI-LINE STOKES INVERSION FOR PROMINENCE MAGNETIC-FIELD DIAGNOSTICS

    International Nuclear Information System (INIS)

    Casini, R.; Lopez Ariste, A.; Paletou, F.; Leger, L.

    2009-01-01

    We present test results on the simultaneous inversion of the Stokes profiles of the He I lines at 587.6 nm (D 3 ) and 1083.0 nm in prominences (90 deg. scattering). We created data sets of synthetic Stokes profiles for the case of quiescent prominences (B -3 of the peak intensity for the polarimetric sensitivity of the simulated observations. In this work, we focus on the error analysis for the inference of the magnetic field vector, under the usual assumption that the prominence can be assimilated to a slab of finite optical thickness with uniform magnetic and thermodynamic properties. We find that the simultaneous inversion of the two lines significantly reduces the errors on the inference of the magnetic field vector, with respect to the case of single-line inversion. These results provide a solid justification for current and future instrumental efforts with multi-line capabilities for the observations of solar prominences and filaments.

  8. Morphology Of A Hot Prominence Cavity Observed with Hinode/XRT and SDO/AIA

    Science.gov (United States)

    Weber, Mark A.; Reeves, K. K.; Gibson, S. E.; Kucera, T. A.

    2012-01-01

    Prominence cavities appear as circularly shaped voids in coronal emission over polarity inversion lines where a prominence channel is straddling the solar limb. The presence of chromospheric material suspended at coronal altitudes is a common but not necessary feature within these cavities. These voids are observed to change shape as a prominence feature rotates around the limb. We use a morphological model projected in cross-sections to fit the cavity emission in Hinode/XRT passbands, and then apply temperature diagnostics to XRT and SDO/AIA data to investigate the thermal structure. We find significant evidence that the prominence cavity is hotter than the corona immediately outside the cavity boundary. This investigation follows upon "Thermal Properties of A Solar Coronal Cavity Observed with the X-ray Telescope on Hinode" by Reeves et al., 2012, ApJ, in press.

  9. QUIESCENT PROMINENCE DYNAMICS OBSERVED WITH THE HINODE SOLAR OPTICAL TELESCOPE. I. TURBULENT UPFLOW PLUMES

    International Nuclear Information System (INIS)

    Berger, Thomas E.; Slater, Gregory; Hurlburt, Neal; Shine, Richard; Tarbell, Theodore; Title, Alan; Lites, Bruce W.; Okamoto, Takenori J.; Ichimoto, Kiyoshi; Katsukawa, Yukio; Magara, Tetsuya; Suematsu, Yoshinori; Shimizu, Toshifumi

    2010-01-01

    Hinode/Solar Optical Telescope (SOT) observations reveal two new dynamic modes in quiescent solar prominences: large-scale (20-50 Mm) 'arches' or 'bubbles' that 'inflate' from below into prominences, and smaller-scale (2-6 Mm) dark turbulent upflows. These novel dynamics are related in that they are always dark in visible-light spectral bands, they rise through the bright prominence emission with approximately constant speeds, and the small-scale upflows are sometimes observed to emanate from the top of the larger bubbles. Here we present detailed kinematic measurements of the small-scale turbulent upflows seen in several prominences in the SOT database. The dark upflows typically initiate vertically from 5 to 10 Mm wide dark cavities between the bottom of the prominence and the top of the chromospheric spicule layer. Small perturbations on the order of 1 Mm or less in size grow on the upper boundaries of cavities to generate plumes up to 4-6 Mm across at their largest widths. All plumes develop highly turbulent profiles, including occasional Kelvin-Helmholtz vortex 'roll-up' of the leading edge. The flows typically rise 10-15 Mm before decelerating to equilibrium. We measure the flowfield characteristics with a manual tracing method and with the Nonlinear Affine Velocity Estimator (NAVE) 'optical flow' code to derive velocity, acceleration, lifetime, and height data for several representative plumes. Maximum initial speeds are in the range of 20-30 km s -1 , which is supersonic for a ∼10,000 K plasma. The plumes decelerate in the final few Mm of their trajectories resulting in mean ascent speeds of 13-17 km s -1 . Typical lifetimes range from 300 to 1000 s (∼5-15 minutes). The area growth rate of the plumes (observed as two-dimensional objects in the plane of the sky) is initially linear and ranges from 20,000 to 30,000 km 2 s -1 reaching maximum projected areas from 2 to 15 Mm 2 . Maximum contrast of the dark flows relative to the bright prominence plasma in

  10. Quiescent Prominence Dynamics Observed with the Hinode Solar Optical Telescope. I. Turbulent Upflow Plumes

    Science.gov (United States)

    Berger, Thomas E.; Slater, Gregory; Hurlburt, Neal; Shine, Richard; Tarbell, Theodore; Title, Alan; Lites, Bruce W.; Okamoto, Takenori J.; Ichimoto, Kiyoshi; Katsukawa, Yukio; Magara, Tetsuya; Suematsu, Yoshinori; Shimizu, Toshifumi

    2010-06-01

    Hinode/Solar Optical Telescope (SOT) observations reveal two new dynamic modes in quiescent solar prominences: large-scale (20-50 Mm) "arches" or "bubbles" that "inflate" from below into prominences, and smaller-scale (2-6 Mm) dark turbulent upflows. These novel dynamics are related in that they are always dark in visible-light spectral bands, they rise through the bright prominence emission with approximately constant speeds, and the small-scale upflows are sometimes observed to emanate from the top of the larger bubbles. Here we present detailed kinematic measurements of the small-scale turbulent upflows seen in several prominences in the SOT database. The dark upflows typically initiate vertically from 5 to 10 Mm wide dark cavities between the bottom of the prominence and the top of the chromospheric spicule layer. Small perturbations on the order of 1 Mm or less in size grow on the upper boundaries of cavities to generate plumes up to 4-6 Mm across at their largest widths. All plumes develop highly turbulent profiles, including occasional Kelvin-Helmholtz vortex "roll-up" of the leading edge. The flows typically rise 10-15 Mm before decelerating to equilibrium. We measure the flowfield characteristics with a manual tracing method and with the Nonlinear Affine Velocity Estimator (NAVE) "optical flow" code to derive velocity, acceleration, lifetime, and height data for several representative plumes. Maximum initial speeds are in the range of 20-30 km s-1, which is supersonic for a ~10,000 K plasma. The plumes decelerate in the final few Mm of their trajectories resulting in mean ascent speeds of 13-17 km s-1. Typical lifetimes range from 300 to 1000 s (~5-15 minutes). The area growth rate of the plumes (observed as two-dimensional objects in the plane of the sky) is initially linear and ranges from 20,000 to 30,000 km2 s-1 reaching maximum projected areas from 2 to 15 Mm2. Maximum contrast of the dark flows relative to the bright prominence plasma in SOT images

  11. Quiescent Prominences in the Era of ALMA. II. Kinetic Temperature Diagnostics

    Science.gov (United States)

    Gunár, Stanislav; Heinzel, Petr; Anzer, Ulrich; Mackay, Duncan H.

    2018-01-01

    We provide the theoretical background for diagnostics of the thermal properties of solar prominences observed by the Atacama Large Millimeter/submillimeter Array (ALMA). To do this, we employ the 3D Whole-Prominence Fine Structure (WPFS) model that produces synthetic ALMA-like observations of a complex simulated prominence. We use synthetic observations derived at two different submillimeter/millimeter (SMM) wavelengths—one at a wavelength at which the simulated prominence is completely optically thin and another at a wavelength at which a significant portion of the simulated prominence is optically thick—as if these were the actual ALMA observations. This allows us to develop a technique for an analysis of the prominence plasma thermal properties from such a pair of simultaneous high-resolution ALMA observations. The 3D WPFS model also provides detailed information about the distribution of the kinetic temperature and the optical thickness along any line of sight. We can thus assess whether the measure of the kinetic temperature derived from observations accurately represents the actual kinetic temperature properties of the observed plasma. We demonstrate here that in a given pixel the optical thickness at the wavelength at which the prominence plasma is optically thick needs to be above unity or even larger to achieve a sufficient accuracy of the derived information about the kinetic temperature of the analyzed plasma. Information about the optical thickness cannot be directly discerned from observations at the SMM wavelengths alone. However, we show that a criterion that can identify those pixels in which the derived kinetic temperature values correspond well to the actual thermal properties in which the observed prominence can be established.

  12. Biomimicry of multifunctional nanostructures in the neck feathers of mallard (Anas platyrhynchos L.) drakes

    Science.gov (United States)

    Khudiyev, Tural; Dogan, Tamer; Bayindir, Mehmet

    2014-04-01

    Biological systems serve as fundamental sources of inspiration for the development of artificially colored devices, and their investigation provides a great number of photonic design opportunities. While several successful biomimetic designs have been detailed in the literature, conventional fabrication techniques nonetheless remain inferior to their natural counterparts in complexity, ease of production and material economy. Here, we investigate the iridescent neck feathers of Anas platyrhynchos drakes, show that they feature an unusual arrangement of two-dimensional (2D) photonic crystals and further exhibit a superhydrophobic surface, and mimic this multifunctional structure using a nanostructure composite fabricated by a recently developed top-down iterative size reduction method, which avoids the above-mentioned fabrication challenges, provides macroscale control and enhances hydrophobicity through the surface structure. Our 2D solid core photonic crystal fibres strongly resemble drake neck plumage in structure and fully polymeric material composition, and can be produced in wide array of colors by minor alterations during the size reduction process.

  13. Contribution of double scattering to structural coloration in quasiordered nanostructures of bird feathers

    Science.gov (United States)

    Noh, Heeso; Liew, Seng Fatt; Saranathan, Vinodkumar; Prum, Richard O.; Mochrie, Simon G. J.; Dufresne, Eric R.; Cao, Hui

    2010-05-01

    We measured the polarization- and angle-resolved optical scattering and reflection spectra of the quasiordered nanostructures in the bird feather barbs. In addition to the primary peak that originates from single scattering, we observed a secondary peak which exhibits depolarization and distinct angular dispersion. We explained the secondary peak in terms of double scattering, i.e., light is scattered successively twice by the structure. The two sequential single-scattering events are considered uncorrelated. Using the Fourier power spectra of the nanostructures obtained from the small-angle x-ray scattering experiment, we calculated the double scattering of light in various directions. The double-scattering spectrum is broader than the single-scattering spectrum, and it splits into two subpeaks at larger scattering angle. The good agreement between the simulation results and the experimental data confirms that double scattering of light makes a significant contribution to the structural color.

  14. Contribution of double scattering to structural coloration in quasiordered nanostructures of bird feathers

    Energy Technology Data Exchange (ETDEWEB)

    Noh, Heeso; Liew, Seng Fatt; Saranathan, Vinodkumar; Prum, Richard O.; Mochrie, Simon G.J.; Dufresne, Eric R.; Cao, Hui (Yale)

    2010-07-28

    We measured the polarization- and angle-resolved optical scattering and reflection spectra of the quasiordered nanostructures in the bird feather barbs. In addition to the primary peak that originates from single scattering, we observed a secondary peak which exhibits depolarization and distinct angular dispersion. We explained the secondary peak in terms of double scattering, i.e., light is scattered successively twice by the structure. The two sequential single-scattering events are considered uncorrelated. Using the Fourier power spectra of the nanostructures obtained from the small-angle x-ray scattering experiment, we calculated the double scattering of light in various directions. The double-scattering spectrum is broader than the single-scattering spectrum, and it splits into two subpeaks at larger scattering angle. The good agreement between the simulation results and the experimental data confirms that double scattering of light makes a significant contribution to the structural color.

  15. Feathering effect detection and artifact agglomeration index-based video deinterlacing technique

    Science.gov (United States)

    Martins, André Luis; Rodrigues, Evandro Luis Linhari; de Paiva, Maria Stela Veludo

    2018-03-01

    Several video deinterlacing techniques have been developed, and each one presents a better performance in certain conditions. Occasionally, even the most modern deinterlacing techniques create frames with worse quality than primitive deinterlacing processes. This paper validates that the final image quality can be improved by combining different types of deinterlacing techniques. The proposed strategy is able to select between two types of deinterlaced frames and, if necessary, make the local correction of the defects. This decision is based on an artifact agglomeration index obtained from a feathering effect detection map. Starting from a deinterlaced frame produced by the "interfield average" method, the defective areas are identified, and, if deemed appropriate, these areas are replaced by pixels generated through the "edge-based line average" method. Test results have proven that the proposed technique is able to produce video frames with higher quality than applying a single deinterlacing technique through getting what is good from intra- and interfield methods.

  16. Tunable alumina 2D photonic-crystal structures via biomineralization of peacock tail feathers

    Science.gov (United States)

    Jiang, Yonggang; Wang, Rui; Feng, Lin; Li, Jian; An, Zhonglie; Zhang, Deyuan

    2018-04-01

    Peacock tail feathers with subtle periodic nanostructures exhibit diverse striking brilliancy, which can be applied as natural templates to fabricate artificial photonic crystals (PhCs) via a biomineralization method. Alumina photonic-crystal structures are successfully synthesized via an immersion and two-step calcination process. The lattice constants of the artificial PhCs are greatly reduced compared to their natural matrices. The lattice constants are tunable by modifying the final annealing conditions in the biomineralization process. The reflection spectra of the alumina photonic-crystal structures are measured, which is related to their material and structural parameters. This work suggests a facile fabrication process to construct alumina PhCs with a high-temperature resistance.

  17. Stable isotope analyses of feather amino acids identify penguin migration strategies at ocean basin scales.

    Science.gov (United States)

    Polito, Michael J; Hinke, Jefferson T; Hart, Tom; Santos, Mercedes; Houghton, Leah A; Thorrold, Simon R

    2017-08-01

    Identifying the at-sea distribution of wide-ranging marine predators is critical to understanding their ecology. Advances in electronic tracking devices and intrinsic biogeochemical markers have greatly improved our ability to track animal movements on ocean-wide scales. Here, we show that, in combination with direct tracking, stable carbon isotope analysis of essential amino acids in tail feathers provides the ability to track the movement patterns of two, wide-ranging penguin species over ocean basin scales. In addition, we use this isotopic approach across multiple breeding colonies in the Scotia Arc to evaluate migration trends at a regional scale that would be logistically challenging using direct tracking alone. © 2017 The Author(s).

  18. Progress of primary feather molt of adult mourning doves in Missouri

    Science.gov (United States)

    Sadler, K.C.; Tomlinson, R.E.; Wight, H.M.

    1970-01-01

    The examination of 7,892 adult doves in Missouri between 1953 and 1965 showed that less than 2.5% of adult doves completed their molt before October 1. Adult doves of both sexes began molting their primary feathers during early June in Missouri and lost the last (tenth) primary during the latter half of October. Approximately 140-150 days were required to complete the molt. Thus, early-hatched immatures, which begin their primary molt 25-30 days after hatching, contributed the bulk of the wings with completed molts in September. By correctly classifying September samples of dove wings with a completed molt as young-of-the-year a more accurate young:adult ratio is obtained.

  19. Bio-inspired flexible joints with passive feathering for robotic fish pectoral fins.

    Science.gov (United States)

    Behbahani, Sanaz Bazaz; Tan, Xiaobo

    2016-05-04

    In this paper a novel flexible joint is proposed for robotic fish pectoral fins, which enables a swimming behavior emulating the fin motions of many aquatic animals. In particular, the pectoral fin operates primarily in the rowing mode, while undergoing passive feathering during the recovery stroke to reduce hydrodynamic drag on the fin. The latter enables effective locomotion even with symmetric base actuation during power and recovery strokes. A dynamic model is developed to facilitate the understanding and design of the joint, where blade element theory is used to calculate the hydrodynamic forces on the pectoral fins, and the joint is modeled as a paired torsion spring and damper. Experimental results on a robotic fish prototype are presented to illustrate the effectiveness of the joint mechanism, validate the proposed model, and indicate the utility of the proposed model for the optimal design of joint depth and stiffness in achieving the trade-off between swimming speed and mechanical efficiency.

  20. The use of passerine feathers to evaluate heavy metal pollution in Central Portugal.

    Science.gov (United States)

    Costa, R A; Petronilho, J M S; Soares, A M V M; Vingada, J V

    2011-03-01

    In 2003, two sampling strategies were applied in order to evaluate metal contamination in passerine bird feathers. One strategy included the use of nest boxes and nestling great tits in a forest habitat (MU). The other strategy focused on the use of mist nets to capture adult blackbirds, robins and blackcaps in a fragmented non-forested habitat (EST). There was a significantly higher concentration of mercury in great tits (1.09 ± 0.40) sampled in MU and also in robins (3.44 ± 0.91) and blackcaps (1.62 ± 1.99) sampled in EST, in comparison to the reference site (0.66 ± 0.68; 2.04 ± 1.12; 0.32 ± 0.43; respectively). Concerning interspecific differences, robins accumulated significantly more metals than blackbirds or blackcaps.

  1. Study on absorption, accumulation and distribution of 90Sr in yellow-feather broiler

    International Nuclear Information System (INIS)

    Shang Zhaorong; Xu Shiming; Zhao Wenhu; Hou Lanxin

    1993-04-01

    The feeding experiment was carried out for yellow-feather broiler with 90 Sr(NO 3 ) 2 having activities of 1.85 x 10 0 ∼ 1.85 x 10 4 Bq/chicken to observe the regular pattern of absorption and distribution of 90 Sr in its organs and tissues. The results are as follows: The absorption rate of 90 Sr by oral feeding is very low. The most of 90 Sr is drained away by daily excreta from the body. The half-time of its feeding is within 24 hours. The accumulated dose varies with the time and different feeding methods. The more 90 Sr is fed, the more 90 Sr is absorbed, however, the uptake rate of 90 Sr is decreasing. The distribution of 90 Sr for bone is very strong and the partition ratio is about 90%. The absorption coefficient of 90 Sr in organs and tissues of broiler is presented

  2. Regularity on absorption and accumulation of 90Sr in yellow-feather broiler (Hypeco)

    International Nuclear Information System (INIS)

    Xu Shiming; Hou Lanxin; Zhao Wenhu; Li Xia; Yang Zhongyuan

    1996-02-01

    The feeding experiment was carried for yellow-feather broiler (Hypeco) with 90 Sr[NO 3 ] 2 having of 1.85 x 10 2 ∼1.85 x 10 5 Bq/chicken to observe the regular pattern of absorption and accumulation of 90 Sr in its organs and tissues. The absorption rate of 90 Sr by oral feeding is very low. The most of 90 Sr is drained away by daily excreta from the body. The half-time of its feeding is within 24 hours. The more 90 Sr is fed, the more 90 Sr is absorbed, however, the uptake rate of 90 Sr is decreasing. The affinity of 90 Sr for bone is very strong and the partition ratio is about 90%∼99%. The absorption coefficient of 90 Sr in organs and tissues of broiler is presented. (2 refs., 9 tabs.)

  3. SOLAR MAGNETIZED TORNADOES: ROTATIONAL MOTION IN A TORNADO-LIKE PROMINENCE

    International Nuclear Information System (INIS)

    Su, Yang; Veronig, Astrid; Temmer, Manuela; Vanninathan, Kamalam; Gömöry, Peter; Wang, Tongjiang; Gan, Weiqun; Li, YouPing

    2014-01-01

    Su et al. proposed a new explanation for filament formation and eruption, where filament barbs are rotating magnetic structures driven by underlying vortices on the surface. Such structures have been noticed as tornado-like prominences when they appear above the limb. They may play a key role as the source of plasma and twist in filaments. However, no observations have successfully distinguished rotational motion of the magnetic structures in tornado-like prominences from other motions such as oscillation and counter-streaming plasma flows. Here we report evidence of rotational motions in a tornado-like prominence. The spectroscopic observations in two coronal lines were obtained from a specifically designed Hinode/EIS observing program. The data revealed the existence of both cold and million-degree-hot plasma in the prominence leg, supporting the so-called prominence-corona transition region. The opposite velocities at the two sides of the prominence and their persistent time evolution, together with the periodic motions evident in SDO/AIA dark structures, indicate a rotational motion of both cold and hot plasma with a speed of ∼5 km s –1

  4. Solar Magnetized Tornadoes: Rotational Motion in a Tornado-like Prominence

    Science.gov (United States)

    Su, Yang; Gömöry, Peter; Veronig, Astrid; Temmer, Manuela; Wang, Tongjiang; Vanninathan, Kamalam; Gan, Weiqun; Li, YouPing

    2014-04-01

    Su et al. proposed a new explanation for filament formation and eruption, where filament barbs are rotating magnetic structures driven by underlying vortices on the surface. Such structures have been noticed as tornado-like prominences when they appear above the limb. They may play a key role as the source of plasma and twist in filaments. However, no observations have successfully distinguished rotational motion of the magnetic structures in tornado-like prominences from other motions such as oscillation and counter-streaming plasma flows. Here we report evidence of rotational motions in a tornado-like prominence. The spectroscopic observations in two coronal lines were obtained from a specifically designed Hinode/EIS observing program. The data revealed the existence of both cold and million-degree-hot plasma in the prominence leg, supporting the so-called prominence-corona transition region. The opposite velocities at the two sides of the prominence and their persistent time evolution, together with the periodic motions evident in SDO/AIA dark structures, indicate a rotational motion of both cold and hot plasma with a speed of ~5 km s-1.

  5. SOLAR MAGNETIZED TORNADOES: ROTATIONAL MOTION IN A TORNADO-LIKE PROMINENCE

    Energy Technology Data Exchange (ETDEWEB)

    Su, Yang; Veronig, Astrid; Temmer, Manuela; Vanninathan, Kamalam [IGAM-Kanzelhöhe Observatory, Institute of Physics, University of Graz, Universitätsplatz 5, A-8010 Graz (Austria); Gömöry, Peter [Astronomical Institute of the Slovak Academy of Sciences, SK-05960 Tatranská Lomnica (Slovakia); Wang, Tongjiang [Department of Physics, the Catholic University of America, Washington, DC 20064 (United States); Gan, Weiqun; Li, YouPing, E-mail: yang.su@uni-graz.at [Key Laboratory of Dark Matter and Space Astronomy, Purple Mountain Observatory, Chinese Academy of Sciences, Nanjing 210008 (China)

    2014-04-10

    Su et al. proposed a new explanation for filament formation and eruption, where filament barbs are rotating magnetic structures driven by underlying vortices on the surface. Such structures have been noticed as tornado-like prominences when they appear above the limb. They may play a key role as the source of plasma and twist in filaments. However, no observations have successfully distinguished rotational motion of the magnetic structures in tornado-like prominences from other motions such as oscillation and counter-streaming plasma flows. Here we report evidence of rotational motions in a tornado-like prominence. The spectroscopic observations in two coronal lines were obtained from a specifically designed Hinode/EIS observing program. The data revealed the existence of both cold and million-degree-hot plasma in the prominence leg, supporting the so-called prominence-corona transition region. The opposite velocities at the two sides of the prominence and their persistent time evolution, together with the periodic motions evident in SDO/AIA dark structures, indicate a rotational motion of both cold and hot plasma with a speed of ∼5 km s{sup –1}.

  6. SOLAR LIMB PROMINENCE CATCHER AND TRACKER (SLIPCAT): AN AUTOMATED SYSTEM AND ITS PRELIMINARY STATISTICAL RESULTS

    International Nuclear Information System (INIS)

    Wang Yuming; Cao Hao; Chen Junhong; Zhang Tengfei; Yu Sijie; Zheng Huinan; Shen Chenglong; Wang, S.; Zhang Jie

    2010-01-01

    In this paper, we present an automated system, which has the capability to catch and track solar limb prominences based on observations from the extreme-ultraviolet (EUV) 304 A passband. The characteristic parameters and their evolution, including height, position angle, area, length, and brightness, are obtained without manual interventions. By applying the system to the STEREO-B/SECCHI/EUVI 304 A data during 2007 April-2009 October, we obtain a total of 9477 well-tracked prominences and a catalog of these events available online. A detailed analysis of these prominences suggests that the system has a rather good performance. We have obtained several interesting statistical results based on the catalog. Most prominences appear below the latitude of 60 0 and at the height of about 26 Mm above the solar surface. Most of them are quite stable during the period they are tracked. Nevertheless, some prominences have an upward speed of more than 100 km s -1 , and some others show significant downward and/or azimuthal speeds. There are strong correlations among the brightness, area, and height. The expansion of a prominence is probably one major cause of its fading during the rising or erupting process.

  7. Quiescent and Eruptive Prominences at Solar Minimum: A Statistical Study via an Automated Tracking System

    Science.gov (United States)

    Loboda, I. P.; Bogachev, S. A.

    2015-07-01

    We employ an automated detection algorithm to perform a global study of solar prominence characteristics. We process four months of TESIS observations in the He II 304Å line taken close to the solar minimum of 2008-2009 and mainly focus on quiescent and quiescent-eruptive prominences. We detect a total of 389 individual features ranging from 25×25 to 150×500 Mm2 in size and obtain distributions of many of their spatial characteristics, such as latitudinal position, height, size, and shape. To study their dynamics, we classify prominences as either stable or eruptive and calculate their average centroid velocities, which are found to rarely exceed 3 km/s. In addition, we give rough estimates of mass and gravitational energy for every detected prominence and use these values to estimate the total mass and gravitational energy of all simultaneously existing prominences (1012 - 1014 kg and 1029 - 1031 erg). Finally, we investigate the form of the gravitational energy spectrum of prominences and derive it to be a power-law of index -1.1 ± 0.2.

  8. EVIDENCE FOR ROTATIONAL MOTIONS IN THE FEET OF A QUIESCENT SOLAR PROMINENCE

    International Nuclear Information System (INIS)

    Orozco Suárez, D.; Asensio Ramos, A.; Trujillo Bueno, J.

    2012-01-01

    We present observational evidence of apparent plasma rotational motions in the feet of a solar prominence. Our study is based on spectroscopic observations taken in the He I 1083.0 nm multiplet with the Tenerife Infrared Polarimeter attached to the German Vacuum Tower Telescope. We recorded a time sequence of spectra with 34 s cadence placing the slit of the spectrograph almost parallel to the solar limb and crossing two feet of an intermediate size, quiescent hedgerow prominence. The data show opposite Doppler shifts, ±6 km s –1 , at the edges of the prominence feet. We argue that these shifts may be interpreted as prominence plasma rotating counterclockwise around the vertical axis to the solar surface as viewed from above. The evolution of the prominence seen in EUV images taken with the Solar Dynamics Observatory provided us with clues to interpret the results as swirling motions. Moreover, time-distance images taken far from the central wavelength show plasma structures moving parallel to the solar limb with velocities of about 10-15 km s –1 . Finally, the shapes of the observed intensity profiles suggest the presence of, at least, two components at some locations at the edges of the prominence feet. One of them is typically Doppler shifted (up to ∼20 km s –1 ) with respect to the other, thus suggesting the existence of supersonic counter-streaming flows along the line of sight.

  9. Prominence Bubbles and Plumes: Thermo-magnetic Buoyancy in Coronal Cavity Systems

    Science.gov (United States)

    Berger, Thomas; Hurlburt, N.

    2009-05-01

    The Hinode/Solar Optical Telescope continues to produce high spatial and temporal resolution images of solar prominences in both the Ca II 396.8 nm H-line and the H-alpha 656.3 nm line. Time series of these images show that many quiescent prominences produce large scale (50 Mm) dark "bubbles" that "inflate" into, and sometimes burst through, the prominence material. In addition, small-scale (2--5 Mm) dark plumes are seen rising into many quiescent prominences. We show typical examples of both phenomena and argue that they originate from the same mechanism: concentrated and heated magnetic flux that rises due to thermal and magnetic buoyancy to equilibrium heights in the prominence/coronal-cavity system. More generally, these bubbles and upflows offer a source of both magnetic flux and mass to the overlying coronal cavity, supporting B.C. Low's theory of CME initiation via steadily increasing magnetic buoyancy breaking through the overlying helmut streamer tension forces. Quiescent prominences are thus seen as the lowermost parts of the larger coronal cavity system, revealing through thermal effects both the cooled downflowing "drainage" from the cavity and the heated upflowing magnetic "plasmoids" supplying the cavity. We compare SOT movies to new 3D compressible MHD simulations that reproduce the dark turbulent plume dynamics to establish the magnetic and thermal character of these buoyancy-driven flows into the corona.

  10. The Fate of Cool Material in the Hot Corona: Solar Prominences and Coronal Rain

    Science.gov (United States)

    Liu, Wei; Antolin, Patrick; Sun, Xudong; Vial, Jean-Claude; Berger, Thomas

    2017-08-01

    As an important chain of the chromosphere-corona mass cycle, some of the million-degree hot coronal mass undergoes a radiative cooling instability and condenses into material at chromospheric or transition-region temperatures in two distinct forms - prominences and coronal rain (some of which eventually falls back to the chromosphere). A quiescent prominence usually consists of numerous long-lasting, filamentary downflow threads, while coronal rain consists of transient mass blobs falling at comparably higher speeds along well-defined paths. It remains puzzling why such material of similar temperatures exhibit contrasting morphologies and behaviors. We report recent SDO/AIA and IRIS observations that suggest different magnetic environments being responsible for such distinctions. Specifically, in a hybrid prominence-coronal rain complex structure, we found that the prominence material is formed and resides near magnetic null points that favor the radiative cooling process and provide possibly a high plasma-beta environment suitable for the existence of meandering prominence threads. As the cool material descends, it turns into coronal rain tied onto low-lying coronal loops in a likely low-beta environment. Such structures resemble to certain extent the so-called coronal spiders or cloud prominences, but the observations reported here provide critical new insights. We will discuss the broad physical implications of these observations for fundamental questions, such as coronal heating and beyond (e.g., in astrophysical and/or laboratory plasma environments).

  11. DYNAMICS OF A PROMINENCE-HORN STRUCTURE DURING ITS EVAPORATION IN THE SOLAR CORONA

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Bing; Chen, Yao; Fu, Jie; Li, Bo [Shandong Provincial Key Laboratory of Optical Astronomy and Solar-Terrestrial Environment, and Institute of Space Sciences, Shandong University, Weihai 264209 (China); Li, Xing [Department of Physics, Aberystwyth University, Aberystwyth, Ceredigion, SY23 3BZ (United Kingdom); Liu, Wei, E-mail: yaochen@sdu.edu.cn [Stanford-Lockheed Institute for Space Research, Stanford University, Stanford, CA 94305 (United States)

    2016-08-20

    The physical connections among and formation mechanisms of various components of the prominence-horn cavity system remain elusive. Here we present observations of such a system, focusing on a section of the prominence that rises and separates gradually from the main body. This forms a configuration sufficiently simple to yield clues regarding the above issues. It is characterized by embedding horns, oscillations, and a gradual disappearance of the separated material. The prominence-horn structure exhibits a large-amplitude longitudinal oscillation with a period of ∼150 minutes and an amplitude of ∼30 Mm along the trajectory defined by the concave horn structure. The horns also experience a simultaneous transverse oscillation with a much smaller amplitude (∼3 Mm) and a shorter period (∼10–15 minutes), likely representative of a global mode of the large-scale magnetic structure. The gradual disappearance of the structure indicates that the horn, an observational manifestation of the field-aligned transition region separating the cool and dense prominence from the hot and tenuous corona, is formed due to the heating and diluting process of the central prominence mass; most previous studies suggested that it is the opposite process, i.e., the cooling and condensation of coronal plasmas, that formed the horn. This study also demonstrates how the prominence transports magnetic flux to the upper corona, a process essential for the gradual build-up of pre-eruption magnetic energy.

  12. Processing of poultry feathers by alkaline keratin hydrolyzing enzyme from Serratia sp. HPC 1383.

    Science.gov (United States)

    Khardenavis, Anshuman A; Kapley, Atya; Purohit, Hemant J

    2009-04-01

    The present study describes the production and characterization of a feather hydrolyzing enzyme by Serratia sp. HPC 1383 isolated from tannery sludge, which was identified by the ability to form clear zones around colonies on milk agar plates. The proteolytic activity was expressed in terms of the micromoles of tyrosine released from substrate casein per ml per min (U/mL min). Induction of the inoculum with protein was essential to stimulate higher activity of the enzyme, with 0.03% feathermeal in the inoculum resulting in increased enzyme activity (45U/mL) that further increased to 90U/mL when 3d old inoculum was used. The highest enzyme activity, 130U/mL, was observed in the presence of 0.2% yeast extract. The optimum assay temperature and pH for the enzyme were found to be 60 degrees C and 10.0, respectively. The enzyme had a half-life of 10min at 60 degrees C, which improved slightly to 18min in presence of 1mM Ca(2+). Inhibition of the enzyme by phenylmethyl sulfonyl fluoride (PMSF) indicated that the enzyme was a serine protease. The enzyme was also partially inhibited (39%) by the reducing agent beta-mercaptoethanol and by divalent metal ions such as Zn(2+) (41% inhibition). However, Ca(2+) and Fe(2+) resulted in increases in enzyme activity of 15% and 26%, respectively. The kinetic constants of the keratinase were found to be 3.84 microM (K(m)) and 108.7 microM/mLmin (V(max)). These results suggest that this extracellular keratinase may be a useful alternative and eco-friendly route for handling the abundant amount of waste feathers or for applications in other industrial processes.

  13. Symplasmic and apoplasmic transport inside feather moss stems of Pleurozium schreberi and Hylocomium splendens.

    Science.gov (United States)

    Sokolowska, K; Turzanska, M; Nilsson, M-C

    2017-11-10

    The ubiquitous feather mosses Pleurozium schreberi and Hylocomium splendens form a thick, continuous boundary layer between the soil and the atmosphere, and play important roles in hydrology and nutrient cycling in tundra and boreal ecosystems. The water fluxes among these mosses and environmental factors controlling them are poorly understood. The aim of this study was to investigate whether feather mosses are capable of internal transport and to provide a better understanding of species-specific morphological traits underlying this function. The impacts of environmental conditions on their internal transport rates were also investigated. Cells involved in water and food conduction in P. schreberi and H. splendens were identified by transmission electron microscopy. Symplasmic and apoplasmic fluorescent tracers were applied to the moss stems to determine the routes of internal short- and long-distance transport and the impact of air humidity on the transport rates. Symplasmic transport over short distances occurs via food-conducting cells in both mosses. Pleurozium schreberi is also capable of apoplasmic internal long-distance transport via a central strand of hydroids. These are absent in H. splendens. Reduced air humidity significantly increased the internal transport of both species, and the increase was significantly faster for P. schreberi than for H. splendens. Pleurozium schreberi and Hylocomium splendens are capable of internal transport but the pathway and conductivity differ due to differences in stem anatomy. These results help explain their varying desiccation tolerance and possibly their differing physiology and autecology and, ultimately, their impact on ecosystem functioning. © The Author 2017. Published by Oxford University Press on behalf of the Annals of Botany Company. All rights reserved. For Permissions, please email: journals.permissions@oup.com

  14. Temporal trends (1989–2011) in levels of mercury and other heavy metals in feathers of fledgling great egrets nesting in Barnegat Bay, NJ

    International Nuclear Information System (INIS)

    Burger, Joanna

    2013-01-01

    There is an abundance of data for levels of metals from a range of species, but relatively few long-term time series from the same location. In this paper I examine the levels of arsenic, cadmium, chromium, lead, manganese, mercury and selenium in feathers from fledgling great egrets (Ardea alba) collected at nesting colonies in Barnegat Bay, New Jersey from 1989 to 2011. The primary objectives were to test the null hypotheses that (1) There were no temporal differences in metal levels in feathers of fledgling great egrets, and (2) Great egrets nesting in different areas of Barnegat Bay (New Jersey) did not differ in metal levels. There were significant yearly variations in levels of all heavy metals in feathers of fledgling great egret, but levels decreased significantly from 1989 to 2011 only for lead (1470 ppb to 54.3 ppb), cadmium (277 ppb to 30.5 ppb), and manganese (only since 1996; 2669 ppb to 329 ppb)). Although mercury levels decreased from 2003–2008 (6430 ppb to 1042 ppb), there was no pattern before 2003, and levels increased after 2008 to 2610 ppb in 2011. Lead, cadmium, chromium, manganese and mercury were higher in feathers from great egrets nesting in the northern part of the bay, and selenium was highest in feathers from mid-bay. The lack of a temporal decline in mercury levels in feathers of great egrets is cause for concern, since the high levels in feathers from some years (means as high as 6430 ppb) are in the range associated with adverse effects (5000 ppb for feathers). -- Highlights: ► Metals were monitored in feathers of great egrets from Barnegat Bay, New Jersey. ► Levels of cadmium and lead decreased significantly from 1989–2011. ► Mercury levels in feathers from great egrets did not decline from 1989–2011. ► Metal levels were generally higher in great egrets and black-crowned night heron feathers than in snowy egrets

  15. The evolution of size of the uropygial gland: mutualistic feather mites and uropygial secretion reduce bacterial loads of eggshells and hatching failures of European birds.

    Science.gov (United States)

    Soler, J J; Peralta-Sánchez, J M; Martín-Platero, A M; Martín-Vivaldi, M; Martínez-Bueno, M; Møller, A P

    2012-09-01

    Potentially, pathogenic bacteria are one of the main infective agents against which a battery of chemical and physical barriers has evolved in animals. Among these are the secretions by the exocrine uropygial gland in birds. The antimicrobial properties of uropygial secretions may prevent colonization and growth of microorganisms on feathers, skin and eggshells. However, uropygial gland secretions also favour the proliferation of feather mites that feed on secretions and microorganisms living on feathers that would otherwise reach eggshells during incubation if not consumed by feather mites. Therefore, at the interspecific level, uropygial gland size (as an index of volume of uropygial secretion) should be positively related to eggshell bacterial load (i.e. the risk of egg infection), whereas eggshell bacterial loads may be negatively related to abundance of feather mites eating bacteria. Here, we explore these previously untested predictions in a comparative framework using information on eggshell bacterial loads, uropygial gland size, diversity and abundance of feather mites and hatching success of 22 species of birds. The size of the uropygial gland was positively related to eggshell bacterial loads (mesophilic bacteria and Enterobacteriaceae), and bird species with higher diversity and abundance of feather mites harboured lower bacterial density on their eggshells (Enterococcus and Staphylococcus), in accordance with the hypothesis. Importantly, eggshell bacterial loads of mesophilic bacteria, Enterococcus and Enterobacteriaceae were negatively associated with hatching success, allowing us to interpret these interspecific relationships in a functional scenario, where both uropygial glands and mutualistic feather mites independently reduce the negative effects of pathogenic bacteria on avian fitness. © 2012 The Authors. Journal of Evolutionary Biology © 2012 European Society For Evolutionary Biology.

  16. Morphological properties of the last primaries, the tail feathers, and the alulae of Accipiter nisus, Columba livia, Falco peregrinus, and Falco tinnunculus.

    Science.gov (United States)

    Schmitz, Anke; Ponitz, Benjamin; Brücker, Christoph; Schmitz, Helmut; Herweg, Jan; Bleckmann, Horst

    2015-01-01

    We investigated the mechanical properties (Young's modulus, bending stiffness, barb separation forces) of the tenth primary of the wings, of the alulae and of the middle tail feathers of Falco peregrinus. For comparison, we also investigated the corresponding feathers in pigeons (Columba livia), kestrels (Falco tinnunculus), and sparrowhawks (Accipiter nisus). In all four species, the Young's moduli of the feathers ranged from 5.9 to 8.4 GPa. The feather shafts of F. peregrinus had the largest cross-sections and the highest specific bending stiffness. When normalized with respect to body mass, the specific bending stiffness of primary number 10 was highest in F. tinnunculus, while that of the alula was highest in A. nisus. In comparison, the specific bending stiffness, measured at the base of the tail feathers and in dorso-ventral bending direction, was much higher in F. peregrinus than in the other three species. This seems to correlate with the flight styles of the birds: F. tinnunculus hovers and its primaries might therefore withstand large mechanical forces. A. nisus has often to change its flight directions during hunting and perhaps needs its alulae for this maneuvers, and in F. peregrinus, the base of the tail feathers might need a high stiffness during breaking after diving. © 2014 Wiley Periodicals, Inc.

  17. Contrasting levels of heavy metals in the feathers of urban pigeons from close habitats suggest limited movements at a restricted scale

    International Nuclear Information System (INIS)

    Frantz, Adrien; Pottier, Marie-Anne; Karimi, Battle; Corbel, Hélène; Aubry, Emmanuel; Haussy, Claudy; Gasparini, Julien; Castrec-Rouelle, Maryse

    2012-01-01

    Despite restrictions in emissions, heavy metals may remain a major environmental issue due to their numerous sources and their persistence. Here, we assessed current levels of 4 metals (Copper, Cadmium, Lead, Zinc) in the feathers of 91 feral pigeons (Columba livia) from 7 sites in the urbanized region of Paris. Elements were detected in all pigeons, indicating that metals persist in urbanized areas. The ratio between metal concentrations in the feathers vs. in the environment calculated using data from other studies was 2–90 times higher for cadmium than for other metals, underlying its ecological importance. Concentrations in the feathers depended on locality, suggesting that pigeons remain in local habitats at this restricted scale, as expected from previous observations. Overall, our study suggests that urban feral pigeons may represent a good model system for metal biomonitoring. Highlights: ► We measured the concentrations of 4 heavy metals in pigeon feathers through Paris. ► Cadmium, Copper, Lead and Zinc were present in pigeons from all 7 sites. ► Metals thus still persist in the city though their emissions have been reduced. ► Metal concentrations in the feathers depended on the local origin of the pigeons. ► These differences suggest limited pigeon movements at a very restricted scale. - Concentrations of metals in the feathers of Parisian feral pigeons (Columba livia) strongly differ at a restricted spatial scale, suggesting limited movements in urban areas.

  18. The use of feathers in monitoring bioaccumulation of metals and metalloids in the South African endangered African grass-owl (Tyto capensis).

    Science.gov (United States)

    Ansara-Ross, T M; Ross, M J; Wepener, V

    2013-08-01

    Few studies have quantified metals in South African species and no published data on residues specifically in South African owl feathers exist. Tyto capensis is listed as vulnerable within South Africa, making it preferable to use a non-invasive technique to determine metal bioaccumulation for this species. Comparisons are made with the cosmopolitan T. alba to determine whether this species could be used as a surrogate. Concentrations of various metals were thus determined in feathers of the two species and compared with liver and muscle samples. Samples were taken from 119 owls collected as road kill along a national road. A comparison of concentrations in feathers revealed similarly higher concentrations of aluminium, antimony, lead, nickel, and strontium, whereas concentrations of chromium, copper, iron, manganese, selenium, titanium and zinc were similarly higher in internal tissues for both species. Metal concentrations of owls were comparable to those reported in literature and below toxic levels, suggesting that these metals were not likely to impact the owls. Further regressions between feathers and corresponding livers were examined to determine if feathers were indicative of internal metal burdens. Significant positive relationships were found for aluminium, copper, lead, nickel and vanadium in T. alba and nickel, manganese and vanadium in T. capensis. Preliminary results support the feasibility of using feathers as non-destructive indicators of environmental contamination in T. capensis although caution needs to be taken when interpreting the results.

  19. Prominence Bubble Shear Flows and the Coupled Kelvin-Helmholtz — Rayleigh-Taylor Instability

    Science.gov (United States)

    Berger, Thomas; Hillier, Andrew

    2017-08-01

    Prominence bubbles are large arched structures that rise from below into quiescent prominences, often growing to heights on the order of 10 Mm before going unstable and generating plume upflows. While there is general agreement that emerging flux below pre-existing prominences causes the structures, there is lack of agreement on the nature of the bubbles and the cause of the instability flows. One hypothesis is that the bubbles contain coronal temperature plasma and rise into the prominence above due to both magnetic and thermal buoyancy, eventually breaking down via a magnetic Rayleigh-Taylor (RT) instability to release hot plasma and magnetic flux and helicity into the overlying coronal flux rope. Another posits that the bubbles are actually just “arcades” in the prominence indicating a magnetic separator line between the bipole and the prominence fields with the observed upflows and downflows caused by reconnection along the separator. We analyze Hinode/SOT, SDO/AIA, and IRIS observations of prominence bubbles, focusing on characteristics of the bubble boundary layers that may discriminate between the two hypotheses. We find speeds on the order of 10 km/s in prominence plasma downflows and lateral shear flows along the bubble boundary. Inflows to the boundary gradually increase the thickness and brightness of the layer until plasma drains from there, apparently around the dome-like bubble domain. In one case, shear flow across the bubble boundary develops Kelvin-Helmholtz (KH) vortices that we use to infer flow speeds in the low-density bubble on the order of 100 km/sec. IRIS spectra indicate that plasma flows on the bubble boundary at transition region temperatures achieve Doppler speeds on the order of 50 km/s, consistent with this inference. Combined magnetic KH-RT instability analysis leads to flux density estimates of 10 G with a field angle of 30° to the prominence, consistent with vector magnetic field measurements. In contrast, we find no evidence

  20. Solar Prominences Embedded in Flux Ropes: Morphological Features and Dynamics from 3D MHD Simulations

    Science.gov (United States)

    Terradas, J.; Soler, R.; Luna, M.; Oliver, R.; Ballester, J. L.; Wright, A. N.

    2016-04-01

    The temporal evolution of a solar prominence inserted in a three-dimensional magnetic flux rope is investigated numerically. Using the model of Titov & Démoulin under the regime of weak twist, the cold and dense prominence counteracts gravity by modifying the initially force-free magnetic configuration. In some cases a quasi-stationary situation is achieved after the relaxation phase, characterized by the excitation of standing vertical oscillations. These oscillations show a strong attenuation with time produced by the mechanism of continuum damping due to the inhomogeneous transition between the prominence and solar corona. The characteristic period of the vertical oscillations does not depend strongly on the twist of the flux rope. Nonlinearity is responsible for triggering the Kelvin-Helmholtz instability associated with the vertical oscillations and that eventually produces horizontal structures. Contrary to other configurations in which the longitudinal axis of the prominence is permeated by a perpendicular magnetic field, like in unsheared arcades, the orientation of the prominence along the flux rope axis prevents the development of Rayleigh-Taylor instabilities and therefore the appearance of vertical structuring along this axis.

  1. ARE TORNADO-LIKE MAGNETIC STRUCTURES ABLE TO SUPPORT SOLAR PROMINENCE PLASMA?

    International Nuclear Information System (INIS)

    Luna, M.; Moreno-Insertis, F.; Priest, E.

    2015-01-01

    Recent high-resolution and high-cadence observations have surprisingly suggested that prominence barbs exhibit apparent rotating motions suggestive of a tornado-like structure. Additional evidence has been provided by Doppler measurements. The observations reveal opposite velocities for both hot and cool plasma on the two sides of a prominence barb. This motion is persistent for several hours and has been interpreted in terms of rotational motion of prominence feet. Several authors suggest that such barb motions are rotating helical structures around a vertical axis similar to tornadoes on Earth. One of the difficulties of such a proposal is how to support cool prominence plasma in almost-vertical structures against gravity. In this work we model analytically a tornado-like structure and try to determine possible mechanisms to support the prominence plasma. We have found that the Lorentz force can indeed support the barb plasma provided the magnetic structure is sufficiently twisted and/or significant poloidal flows are present

  2. Are Tornado-Like Magnetic Structures Able to Support Solar Prominence Plasma?

    Science.gov (United States)

    Ogunjo, S. T.; Luna Bennasar, M.; Moreno-Insertis, F.; Priest, E. R.

    2015-12-01

    Recent high-resolution and high-cadence observations have surprisingly suggested that prominence barbs exhibit apparent rotating motions suggestive of a tornado-like structure. Additional evidence has been provided by Doppler measurements. The observations reveal opposite velocities for both hot and cool plasma on the two sides of a prominence barb. This motion is persistent for several hours and has been interpreted in terms of rotational motion of prominence feet. Several authors suggest that such barb motions are rotating helical structures around a vertical axis similar to tornadoes on Earth. One of the difficulties of such a proposal is how to support cool prominence plasma in almost-vertical structures against gravity. In this work we model analytically a tornado-like structure and try to determine possible mechanisms to support the prominence plasma. We have found that the Lorentz force can indeed support the barb plasma provided the magnetic structure is sufficiently twisted and/or significant poloidal flows are present.

  3. ARE TORNADO-LIKE MAGNETIC STRUCTURES ABLE TO SUPPORT SOLAR PROMINENCE PLASMA?

    Energy Technology Data Exchange (ETDEWEB)

    Luna, M.; Moreno-Insertis, F. [Instituto de Astrofísica de Canarias, E-38200 La Laguna, Tenerife (Spain); Priest, E. [Mathematics Institute, University of St Andrews, St Andrews KY16 9SS (United Kingdom)

    2015-07-20

    Recent high-resolution and high-cadence observations have surprisingly suggested that prominence barbs exhibit apparent rotating motions suggestive of a tornado-like structure. Additional evidence has been provided by Doppler measurements. The observations reveal opposite velocities for both hot and cool plasma on the two sides of a prominence barb. This motion is persistent for several hours and has been interpreted in terms of rotational motion of prominence feet. Several authors suggest that such barb motions are rotating helical structures around a vertical axis similar to tornadoes on Earth. One of the difficulties of such a proposal is how to support cool prominence plasma in almost-vertical structures against gravity. In this work we model analytically a tornado-like structure and try to determine possible mechanisms to support the prominence plasma. We have found that the Lorentz force can indeed support the barb plasma provided the magnetic structure is sufficiently twisted and/or significant poloidal flows are present.

  4. Prominent extraaxial CSF space on cranial ultrasound in infants: correlation with neurodevelopmental outcome

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Bo Kyung; Lee, Mun Hyang; Yoon, Hye Kyung; Jung, Kyung Jae; Park, Won Soon; Chang, Yun Sil; Kim, Chan Gyo [Sungkyunkwan Univ. School of Medicine, Seoul (Korea, Republic of)

    1999-08-01

    To determine the clinical significance of prominent extra-axial CSF space (EACSFS) in infants, as seen on cranial ultrasound. Between March 1996 and November 1997, all infants who had undergone head ultrasound at our institution and were found to have prominent EACSFS were evaluated. The width of the interhemispheric fissure was measured at three locations at the level of the frontal horn, body and atrium of the lateral ventricles. The depth of the CSF space over the convexity was also measured. The average of these measurements was calculated and each patient was assigned to one of three groups: mild, moderate, or marked. Ultrasound findings were evaluated for other associated abnormalities. Clinical neurodevelopment was evaluated by a pediatric neurologist, and ultrasound and neurodevelopmental findings were correlated. Prominent EACSFS was found in 153 patients, and neurodevelopmental evaluation up to a corrected age of 9 months was available in 133. One hundred and eight of 117 infants with normal neurodevelopment had no other associated abnormality(n=81), or abnormality associated only with grade I subependymal hemorrhage or cyst(n=27). Twelve of 16 infants with an abnormal neurodevelopmental outcome had major abnormalities including PVL, grade IV hemorrhage, and marked ventriculomegaly. Prominent EACSFS alone does not appear to be clinically significant. An abnormal neurodevelopmental outcome is associated with major abnormalities seen on ultrasound. Follow-up examination for prominent EACSFS is not indicated unless the associated abnormality requires further evaluations.

  5. Prominent extraaxial CSF space on cranial ultrasound in infants: correlation with neurodevelopmental outcome

    International Nuclear Information System (INIS)

    Kim, Bo Kyung; Lee, Mun Hyang; Yoon, Hye Kyung; Jung, Kyung Jae; Park, Won Soon; Chang, Yun Sil; Kim, Chan Gyo

    1999-01-01

    To determine the clinical significance of prominent extra-axial CSF space (EACSFS) in infants, as seen on cranial ultrasound. Between March 1996 and November 1997, all infants who had undergone head ultrasound at our institution and were found to have prominent EACSFS were evaluated. The width of the interhemispheric fissure was measured at three locations at the level of the frontal horn, body and atrium of the lateral ventricles. The depth of the CSF space over the convexity was also measured. The average of these measurements was calculated and each patient was assigned to one of three groups: mild, moderate, or marked. Ultrasound findings were evaluated for other associated abnormalities. Clinical neurodevelopment was evaluated by a pediatric neurologist, and ultrasound and neurodevelopmental findings were correlated. Prominent EACSFS was found in 153 patients, and neurodevelopmental evaluation up to a corrected age of 9 months was available in 133. One hundred and eight of 117 infants with normal neurodevelopment had no other associated abnormality(n=81), or abnormality associated only with grade I subependymal hemorrhage or cyst(n=27). Twelve of 16 infants with an abnormal neurodevelopmental outcome had major abnormalities including PVL, grade IV hemorrhage, and marked ventriculomegaly. Prominent EACSFS alone does not appear to be clinically significant. An abnormal neurodevelopmental outcome is associated with major abnormalities seen on ultrasound. Follow-up examination for prominent EACSFS is not indicated unless the associated abnormality requires further evaluations

  6. A Discourse Perspective of Topic-prominence in Chinese EFL Learners’ Interlanguage

    Directory of Open Access Journals (Sweden)

    Shaopeng Li

    2014-07-01

    Full Text Available The present study aims to investigate the general characteristics of topic-prominent typological interlanguage development of Chinese learners of English in terms of acquiring subject-prominent English structures from the discourse perspective. We have selected as the research target “topic chain” which is the main topic-prominent structure in Chinese discourse and “zero anaphora” which is the most common topic anaphor of topic chain. Topic structures mainly appear in Chinese discourse in the form of “topic chain” (Wang, 2002; 2004. Actually, in the event of a topic chain, research on topic structures should go into the typical range of discourse. Two important findings were yielded by the present study. First, the characteristics of Chinese topic chain are transferrable to the interlanguage of Chinese EFL learners, thus resulting in overgeneralization of zero anaphora; second, interlanguage discourse of Chinese EFL learners reflects the characteristics of a second language acquisition process from topic-prominence to subject-prominence, thus lending support to the discourse transfer hypothesis.

  7. HELICAL MOTIONS OF FINE-STRUCTURE PROMINENCE THREADS OBSERVED BY HINODE AND IRIS

    Energy Technology Data Exchange (ETDEWEB)

    Okamoto, Takenori J. [National Astronomical Observatory of Japan, Mitaka, Tokyo 181-8588 (Japan); Liu, Wei [Bay Area Environmental Research Institute, 625 2nd Street, Suite 209, Petaluma, CA 94952 (United States); Tsuneta, Saku, E-mail: joten.okamoto@nao.ac.jp [ISAS/JAXA, Sagamihara, Kanagawa 252-5210 (Japan)

    2016-11-10

    Fine-structure dynamics in solar prominences holds critical clues to understanding their physical nature of significant space-weather implications. We report evidence of rotational motions of horizontal helical threads in two active-region prominences observed by the Hinode and/or Interface Region Imaging Spectrograph satellites at high resolution. In the first event, we found transverse motions of brightening threads at speeds up to 55 km s{sup -1} seen in the plane of the sky. Such motions appeared as sinusoidal space–time trajectories with a typical period of ∼390 s, which is consistent with plane-of-sky projections of rotational motions. Phase delays at different locations suggest the propagation of twists along the threads at phase speeds of 90–270 km s{sup -1}. At least 15 episodes of such motions occurred in two days, none associated with an eruption. For these episodes, the plane-of-sky speed is linearly correlated with the vertical travel distance, suggestive of a constant angular speed. In the second event, we found Doppler velocities of 30–40 km s{sup -1} in opposite directions in the top and bottom portions of the prominence, comparable to the plane-of-sky speed. The moving threads have about twice broader line widths than stationary threads. These observations, when taken together, provide strong evidence for rotations of helical prominence threads, which were likely driven by unwinding twists triggered by magnetic reconnection between twisted prominence magnetic fields and ambient coronal fields.

  8. SOLAR PROMINENCES EMBEDDED IN FLUX ROPES: MORPHOLOGICAL FEATURES AND DYNAMICS FROM 3D MHD SIMULATIONS

    Energy Technology Data Exchange (ETDEWEB)

    Terradas, J.; Soler, R.; Oliver, R.; Ballester, J. L. [Departament de Física, Universitat de les Illes Balears, E-07122 Palma de Mallorca (Spain); Luna, M. [Instituto de Astrofsíca de Canarias, E-38205 La Laguna, Tenerife (Spain); Wright, A. N., E-mail: jaume.terradas@uib.es [School of Mathematics and Statistics, University of St Andrews, St Andrews, KY16 9SS (United Kingdom)

    2016-04-01

    The temporal evolution of a solar prominence inserted in a three-dimensional magnetic flux rope is investigated numerically. Using the model of Titov and Démoulin under the regime of weak twist, the cold and dense prominence counteracts gravity by modifying the initially force-free magnetic configuration. In some cases a quasi-stationary situation is achieved after the relaxation phase, characterized by the excitation of standing vertical oscillations. These oscillations show a strong attenuation with time produced by the mechanism of continuum damping due to the inhomogeneous transition between the prominence and solar corona. The characteristic period of the vertical oscillations does not depend strongly on the twist of the flux rope. Nonlinearity is responsible for triggering the Kelvin–Helmholtz instability associated with the vertical oscillations and that eventually produces horizontal structures. Contrary to other configurations in which the longitudinal axis of the prominence is permeated by a perpendicular magnetic field, like in unsheared arcades, the orientation of the prominence along the flux rope axis prevents the development of Rayleigh–Taylor instabilities and therefore the appearance of vertical structuring along this axis.

  9. 78 FR 69691 - Draft Guidance for Industry on Product Name Placement, Size, and Prominence in Advertising and...

    Science.gov (United States)

    2013-11-20

    ...] Draft Guidance for Industry on Product Name Placement, Size, and Prominence in Advertising and... entitled ``Product Name Placement, Size, and Prominence in Advertising and Promotional Labeling.'' When... promotional labeling and advertising for prescription human drugs, including biological drug products, and...

  10. Cell structure of developing barbs and barbules in downfeathers of the chick: Central role of barb ridge morphogenesis for the evolution of feathers.

    Science.gov (United States)

    Alibardi, L

    2005-04-01

    The present ultrastructural study shows how cells organize to form the complex structure of downfeathers in chick embryos. The embryonic epidermis of the apical part of feather filaments folds inward forming barb ridges which extend toward the base of the feather. The stratification of epidermal cells in barb ridges is maintained but the basal layer loses most of the germinal activity. New cells for the growth of feather filaments are mainly produced in its basal part. In barb ridges only the original four epidermal layers of the embryonic epidermis remain to form feathers: 1) the external periderm, 2) three-five layers of the feather sheath and barb vane ridge cells, 3) subperiderm cells, and 4) basal or cylindrical cells. Periderm, sheath, barb vane ridge and cylindrical cells synthesize only alpha-keratin. Instead, cells of the subperiderm layer synthesize a small type of beta-keratin: feather beta-keratin. At hatching, the subperiderm layer is lost in most areas of the skin of the chick (apteric and scaled), and is replaced by cells containing alpha-keratin (interfollicular-apteric epidermis), scale beta-keratin (scales), beak beta-keratin (beak), and claw beta-keratin (claws). Only in feathers, cells of the original subperiderm layer remain and give origin to barb and barbule cells. The formation of separated chains of barb and barbule cells is allowed by the presence of barb vane ridge cells that function as spacers between merging cells of barb and barbule cells. Subperiderm cells elongate and merge into a syncitium to form barbules and barbs. While barbule and barb cells accumulate feather-keratin, barb vane and cylindrical cells accumulate lipids, vesicles and little alpha-keratin. These cells eventually degenerate by necrosis leaving empty spaces and lipids between barbules and barbs. No apoptosis is necessary to explain the process of carving out of barb and barbules in feathers after dissolution of the external sheath. In fact, the retraction of blood

  11. Identity and diversity of archaeal communities during anaerobic co-digestion of chicken feathers and other animal wastes.

    Science.gov (United States)

    Xia, Yun; Massé, Daniel I; McAllister, Tim A; Kong, Yunhong; Seviour, Robert; Beaulieu, Carole

    2012-04-01

    Digestion of raw feathers in anaerobic digesters inoculated with adapted swine manure, slaughterhouse sludge or dairy manure was investigated using twelve 42-L anaerobic digesters at 25°C. After 120days 74%, 49% and 40% added feathers were converted to methane in swine manure, dairy manure and slaughterhouse sludge anaerobic digesters respectively. 16S rRNA gene clone library analyses identified twenty-one operational taxonomic units containing clone sequences from 5 genera, 5 families and 2 phyla of members of the Archaea from 158 sequenced clones. Fluorescence insitu hybridization revealed that methanogens from the Methanomicrobiales, Methanosarcinales and Methanobacteriales constituted a major fraction (>78%) of these Archaea. A high correlation was seen between the distribution of functional archaeal groups and the NH(3)-N levels of digester mixed liquors. The compositions of archaeal communities fed different substrates were statistically significantly different (P<0.05). Crown Copyright © 2012. Published by Elsevier Ltd. All rights reserved.

  12. SYNTHETIC HYDROGEN SPECTRA OF OSCILLATING PROMINENCE SLABS IMMERSED IN THE SOLAR CORONA

    International Nuclear Information System (INIS)

    Zapiór, M.; Heinzel, P.; Oliver, R.; Ballester, J. L.

    2016-01-01

    We study the behavior of H α and H β spectral lines and their spectral indicators in an oscillating solar prominence slab surrounded by the solar corona, using an MHD model combined with a 1D radiative transfer code taken in the line of sight perpendicular to the slab. We calculate the time variation of the Doppler shift, half-width, and maximum intensity of the H α and H β spectral lines for different modes of oscillation. We find a non-sinusoidal time dependence of some spectral parameters with time. Because H α and H β spectral indicators have different behavior for different modes, caused by differing optical depths of formation and different plasma parameter variations in time and along the slab, they may be used for prominence seismology, especially to derive the internal velocity field in prominences.

  13. The EU and Climate Change Policy: Law, Politics and Prominence at Different Levels

    Directory of Open Access Journals (Sweden)

    Chad David Damro

    2008-11-01

    Full Text Available The European Union (EU is a prominent player in the politics of climate change, operating as an authoritative regional actor that influences policy-making at the national and international levels. The EU’s climate change policies are thus subjected to multiple pressures that arise from the domestic politics of its twenty-seven individual member states and the international politics of non-EU states with which it negotiates. Facing these multiple pressures, how and why could such a non-traditional actor develop into a prominent player at different levels of climate change policy-making? This article argues that the EU’s rise to prominence can be understood by tracking a number of historical-legal institutional developments at the domestic and international levels. The article also provides a preliminary investigation of the EU emissions trading scheme, a new institutional mechanism that illustrates the policy pressures arising from different levels.

  14. Liking goes with liking: An intuitive congruence between preference and prominence.

    Science.gov (United States)

    Morvinski, Coby; Amir, On

    2018-03-26

    In a series of 8 experiments, we demonstrate the existence of a "labeling effect" wherein people intuitively relate preferred choices to prominently labeled cues (such as heads as opposed to tails in a coin toss) and vice versa. Importantly, the observed congruence is asymmetric-it does not manifest for nonprominent cues and nonpreferred choices. This is because the congruence is driven by a process of evaluative matching: prominent cues are liked, but nonprominent cues are neutral or at most slightly negative in contrast. When we test prominent, yet truly negatively labeled cues, we indeed find a matching with less liked products. We discuss the theoretical contributions to the study of preferences and decision making, as well as demonstrate the practical implications to researchers and practitioners by using this process to assess intuitive preferences and reduce the compromise effect. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

  15. Subcision Using a Spinal Needle Cannula and a Thread for Prominent Nasolabial Fold Correction

    Directory of Open Access Journals (Sweden)

    Sang-Yeul Lee

    2013-05-01

    Full Text Available Deepening of the nasolabial crease is an esthetically unpleasing aging phenomenon occurring in the midface. Various treatment modalities have been introduced to improve the appearance of prominent nasolabial folds, all of which have pros and cons. Currently, a minimally invasive technique using synthetic dermal fillers is most commonly used. A simple and easy subcision procedure using a wire scalpel has also been used and reported to be effective for prominent nasolabial fold correction, with minimal complications. As an alternative to the wire scalpel, we used a 20-gauge metal type spinal needle cannula (Hakko Co. and 4-0 Vicryl suture (Ethicon Inc. for subcision of nasolabial folds. This technique is less expensive than the use of a wire scalpel and easily available when needed. Therefore, on the basis of favorable results, our modified subcision technique may be considered effective for prominent nasolabial fold correction.

  16. A twisted flux-tube model for solar prominences. I. General properties

    International Nuclear Information System (INIS)

    Priest, E.R.; Hood, A.W.; Anzer, U.

    1989-01-01

    It is proposed that a solar prominence consists of cool plasma supported in a large-scale curved and twisted magnetic flux tube. As long as the flux tube is untwisted, its curvature is concave toward the solar surface, and so it cannot support dense plasma against gravity. However, when it is twisted sufficiently, individual field lines may acquire a convex curvature near their summits and so provide support. Cool plasma then naturally tends to accumulate in such field line dips either by injection from below or by thermal condensation. As the tube is twisted up further or reconnection takes place below the prominence, one finds a transition from normal to inverse polarity. When the flux tube becomes too long or is twisted too much, it loses stability and its true magnetic geometry as an erupting prominence is revealed more clearly. 56 refs

  17. SYNTHETIC HYDROGEN SPECTRA OF OSCILLATING PROMINENCE SLABS IMMERSED IN THE SOLAR CORONA

    Energy Technology Data Exchange (ETDEWEB)

    Zapiór, M.; Heinzel, P. [Astronomical Institute, The Czech Academy of Sciences, 25165 Ondřejov, The Czech Republic (Czech Republic); Oliver, R.; Ballester, J. L. [Universitat de les Illes Balears. Cra. de Valldemossa, km 7.5. Palma (Illes Balears), E-07122 (Spain)

    2016-08-20

    We study the behavior of H α and H β spectral lines and their spectral indicators in an oscillating solar prominence slab surrounded by the solar corona, using an MHD model combined with a 1D radiative transfer code taken in the line of sight perpendicular to the slab. We calculate the time variation of the Doppler shift, half-width, and maximum intensity of the H α and H β spectral lines for different modes of oscillation. We find a non-sinusoidal time dependence of some spectral parameters with time. Because H α and H β spectral indicators have different behavior for different modes, caused by differing optical depths of formation and different plasma parameter variations in time and along the slab, they may be used for prominence seismology, especially to derive the internal velocity field in prominences.

  18. Relative contributions of pigments and biophotonic nanostructures to natural color production: a case study in budgerigar (Melopsittacus undulatus) feathers.

    Science.gov (United States)

    D'Alba, Liliana; Kieffer, Leah; Shawkey, Matthew D

    2012-04-15

    Understanding the mechanistic bases of natural color diversity can provide insight into its evolution and inspiration for biomimetic optical structures. Metazoans can be colored by absorption of light from pigments or by scattering of light from biophotonic nanostructures, and these mechanisms have largely been treated as distinct. However, the interactions between them have rarely been examined. Captive breeding of budgerigars (Aves, Psittacidae, Melopsittacus undulatus) has produced a wide variety of color morphs spanning the majority of the spectrum visible to birds, including the ultraviolet, and thus they have been used as examples of hypothesized structure-pigment interactions. However, empirical data testing these interactions in this excellent model system are lacking. Here we used ultraviolet-visible spectrometry, light and electron microscopy, pigment extraction experiments and optical modeling to examine the physical bases of color production in seven budgerigar morphs, including grey and chromatic (purple to yellow) colors. Feathers from all morphs contained quasi-ordered air-keratin 'spongy layer' matrices, but these were highly reduced and irregular in grey and yellow feathers. Similarly, all feathers but yellow and grey had a layer of melanin-containing melanosomes basal to the spongy layer. The presence of melanosomes likely increases color saturation produced by spongy layers whereas their absence may allow increased expression of yellow colors. Finally, extraction of yellow pigments caused some degree of color change in all feathers except purple and grey, suggesting that their presence and contribution to color production is more widespread than previously thought. These data illustrate how interactions between structures and pigments can increase the range of colors attainable in birds and potentially in synthetic systems.

  19. A new helical crossed-fibre structure of β-keratin in flight feathers and its biomechanical implications.

    Directory of Open Access Journals (Sweden)

    Theagarten Lingham-Soliar

    Full Text Available The feather aerofoil is unequalled in nature. It is comprised of a central rachis, serial paired branches or barbs, from which arise further branches, the barbules. Barbs and barbules arise from the significantly thinner lateral walls (the epicortex of the rachis and barbs respectively, as opposed to the thicker dorsal and ventral walls (the cortex. We hypothesized a microstructural design of the epicortex that would resist the vertical or shearing stresses. The microstructures of the cortex and epicortex of the rachis and barbs were investigated in several bird species by microbe-assisted selective disassembly and conventional methods via scanning electron microscopy. We report, preeminent of the finds, a novel system of crossed fibres (ranging from ∼100-800 nm in diameter, oppositely oriented in alternate layers of the epicortex in the rachis and barbs. It represents the first cross-fibre microstructure, not only for the feather but in keratin per se. The cortex of the barbs is comprised of syncitial barbule cells, definitive structural units shown in the rachidial cortex in a related study. The structural connection between the cortex of the rachis and barbs appears uninterrupted. A new model on feather microstructure incorporating the findings here and in the related study is presented. The helical fibre system found in the integument of a diverse range of invertebrates and vertebrates has been implicated in profound functional strategies, perhaps none more so potentially than in the aerofoil microstructure of the feather here, which is central to one of the marvels of nature, bird flight.

  20. Altered Circulating Levels of Serotonin and Immunological Changes in Laying Hens Divergently Selected for Feather Pecking Behavior

    DEFF Research Database (Denmark)

    Buitenhuis, Albert Johannes; Kjaer, Jørgen B.; Labouriau, Rodrigo

    2006-01-01

    The aim of this study was to investigate the changes in immunological parameters as well as changes with respect to plasma levels of serotonin and tryptophan in lines selected for and against feather pecking (FP) behavior [high FP (HP) line and low FP (LP) line] for 5 generations. The hens from...... response to infectious bursal disease virus vaccination after 1 wk post-vaccination compared with the control and LP lines. The number of white blood cells (P

  1. Five new feather mites of the subfamily Pterodectinae (Acariformes: Astigmata: Proctophyllodidae) from passerines and hummingbirds (Aves) of Brazil.

    Science.gov (United States)

    Hernandes, Fabio Akashi; Pedroso, Luiz Gustavo A; Oniki-Willis, Yoshika

    2016-09-06

    Five new species of feather mites (Proctophyllodidae: Pterodectinae) are described from passerines and hummingbirds of Brazil: Amerodectes longifuscus sp. nov. from Poospiza lateralis (Nordmann, 1835) (Passeriformes: Emberizidae), A. vireonis sp. nov. from Vireo olivaceus (Linnaeus, 1766) (Passeriformes: Vireonidae), Tyrannidectes synallaxis sp. nov. from Synallaxis ruficapilla Vieillot, 1819 (Passeriformes: Furnariidae), Trochilodectes willisi sp. nov. from Phaethornis eurynome (Lesson, 1832) (Apodiformes: Trochilidae), and Xynonodectes phaethornis sp. nov. from Ph. pretrei (Lesson & Delattre, 1839) (Apodiformes: Trochilidae).

  2. Vaginal orgasm is more prevalent among women with a prominent tubercle of the upper lip.

    Science.gov (United States)

    Brody, Stuart; Costa, Rui Miguel

    2011-10-01

    Recent studies have uncovered multiple markers of vaginal orgasm history (unblocked pelvic movement during walking, less use of immature psychological defense mechanisms, greater urethrovaginal space). Other markers (perhaps of prenatal origin) even without obvious mechanistic roles in vaginal orgasm might exist, and a clinical observation led to the novel hypothesis that a prominent tubercle of the upper lip is such a marker. To examine the hypothesis that a prominent tubercle of the upper lip is associated specifically with greater likelihood of experiencing vaginal orgasm (orgasm elicited by penile-vaginal intercourse [PVI] without concurrent masturbation). Women (N = 258, predominantly Scottish) completed an online survey reporting their frequencies of various sexual activities and corresponding orgasms, age, and the prominence of the tubercle of their upper lip. Social desirability response bias was also assessed. Multivariate associations of lip tubercle prominence with vaginal orgasm (ever and past month consistency) and with orgasm by other means. RESULTS.: A prominent and sharply raised lip tubercle was associated with greater odds (odds ratio = 12.3) of ever having a vaginal orgasm, and also with greater past month vaginal orgasm consistency (an effect driven by the women who never had a vaginal orgasm), than less prominent lip tubercle categories. Lip tubercle was not associated with social desirability responding, or with orgasm triggered by masturbation during PVI, solitary or partner clitoral or vaginal masturbation, vibrator, or cunnilingus. The results are discussed in light of the unique nature of vaginal orgasm and the possibility of prenatal developmental influences. © 2011 International Society for Sexual Medicine.

  3. Establishing the Thematic Structure and Investigating the most Prominent Theta Roles Used in Sindhi Language

    Directory of Open Access Journals (Sweden)

    Zahid Ali Veesar

    2015-07-01

    Full Text Available This study focuses on the thematic structure of the Sindhi verbs to find theta roles in the Sindhi language. The study tries to answer the research questions; “What are the thematic structures of Sindhi verbs?” and “What are the prominent theta roles in the Sindhi language?” It examines the argument/thematic structure of Sindhi verbs and also finds the theta roles assigned by the Sindhi verbs to their arguments along with the most prominent theta roles used in the Sindhi language. The data come from the two interviews taken from two young native Sindhi speakers, which consist of 2 hours conversation having 1,669 sentences in natural spoken version of the Sindhi language. Towards the end, it has been found that the Sindhi language has certain theta roles which are assigned by the verbs to their arguments in sentences. Each verb phrase in our data is thus examined and studied in detail in terms of Argument/Thematic structure in order to find theta roles in Sindhi language. Thus, in this regard, each verb phrase (in a sentence has been examined with the help of Carnie’s theoretical framework (Thematic Relation and Theta Roles: 2006 in order to find the prominent theta roles in the Sindhi language. The data have been examined and analysed on the basis of the Carnie’s theoretical framework. The study finds that the Sindhi language has all (09 theta roles which have been proposed by Carnie (2006. It has been found that six prominent theta roles out of nine are used prominently in Sindhi. The six prominent theta roles in Sindhi language are: agent, theme, beneficiary, recipient, locative and goal.

  4. Eliciting extra prominence in read-speech tasks: The effects of different text-highlighting methods on acoustic cues to perceived prominence

    DEFF Research Database (Denmark)

    Berger, Stephanie; Niebuhr, Oliver; Fischer, Kerstin

    2018-01-01

    The research initiative Innovating Speech EliCitation Techniques (INSPECT) aims to describe and quantify how recording methods, situations and materials influence speech produc-tion in lab-speech experiments. On this basis, INSPECT aims to develop methods that reliably stimulate specific patterns...... and styles of speech, like expressive or conversational speech or different types emphatic accents. The present study investigates if and how different text highlighting methods (yellow background, bold, capital letter, italics, and underlining) make speakers reinforce the level of perceived prominence...

  5. Synthesis of feather-like CeO2 microstructures and enzymatic electrochemical catalysis for trichloroacetic acid

    Science.gov (United States)

    Xiao, Xin; Zhang, Dong En; Zhang, Fan; Gong, Jun Yan; Zhang, Xiao Bo; Wang, Yi Hui; Ma, Juan Juan; Tong, Zhi Wei

    Novel feather-like CeO2 microstructures were achieved by a thermal decomposition approach of Ce(OH)CO3 precursor. The Ce(OH)CO3 was obtained from a solvothermal method employing Ce(NO3)3.6H2O with C6H12N4 and C16H33(CH3)3NBr (CTAB) at 190∘C in a water-PEG-200 mixed solution. The feather-like CeO2 dendrite was obtained by thermal conversion of the feather-like Ce(OH)CO3 at 650∘C in air. A reasonable growth mechanism was proposed with the soft-template effect of PEG-200. The electrochemical behavior and enzyme activity of myoglobin (Mb) immobilized on CeO2-Nafion modified glassy carbon electrode (GCE) are demonstrated by cyclic voltammetric measurements. The results indicate that CeO2 can obviously promote the direct electron transfer between the Mb redox centers and the electrode. The Mb on CeO2-Nafion behaves as an elegant performance on the electrochemical reduction of trichloroacetic acid (TCA) from 0.32μM to 2.28μM. The detection limit is estimated to be 0.08μM.

  6. Freundlich and Langmuir adsorption isotherms and kinetics for the removal of Tartrazine from aqueous solutions using hen feathers

    International Nuclear Information System (INIS)

    Mittal, Alok; Kurup, Lisha; Mittal, Jyoti

    2007-01-01

    Tartrazine, a yellow menace, is widely being used in cosmetics, foodstuffs, medicines and textile. It is carcinogenic and also catalyzes allergic problems. In the present work the ability to remove Tartrazine from aqueous solutions has been studied using waste material-hen feathers, as adsorbent. Effects of pH, concentration of the dye, temperature and adsorbent dosage have been studied. Equilibrium isotherms for the adsorption of the dye were measured experimentally. Results were analyzed by the Freundlich and Langmuir equation at different temperatures and determined the characteristic parameters for each adsorption isotherm. The adsorption process has been found endothermic in nature and thermodynamic parameters, Gibb's free energy (ΔG o ), change in enthalpy (ΔH o ) and change in entropy (ΔS o ) have been calculated. The paper also includes results on the kinetic measurements of adsorption of the dye on hen feathers at different temperatures. By rate expression and treatment of data it has been established that the adsorption of Tartrazine over hen feathers follows a first-order kinetics and a film diffusion mechanism operates at all the temperatures

  7. Effective feather degradation and keratinase production by Bacillus pumilus GRK for its application as bio-detergent additive.

    Science.gov (United States)

    Ramakrishna Reddy, M; Sathi Reddy, K; Ranjita Chouhan, Y; Bee, Hameeda; Reddy, Gopal

    2017-11-01

    An effecient feather-degrading bacterium was isolated from poultry dumping yard and identified as Bacillus pumilus GRK based on 16S rRNA sequencing. Complete feather degradation (98.3±1.52%) with high keratinase production (373±4 U/ml) was observed in 24h under optimized conditions (substrate 1% (w/w); inoculum size 4% (v/v); pH 10; 200rpm at 37°C) with feathers as sole carbon and nitrogen source in tap water. The fermented broth was enriched with amino acids like tryptophan (221.44µg/ml), isoleucine (15.0µg/ml), lysine (10.81µg/ml) and methionine (7.24µg/ml) suggesting its potential use as feed supplement. The keratinase produced was a detergent stable serine protease and its activity was further enhanced by Ca +2 and Mg +2 . Bacillus pumilus GRK keratinase was successfully utilised as bioadditive in detergent formulations for removing the blood stains from cloth without affecting its fiber and texture. Copyright © 2017 Elsevier Ltd. All rights reserved.

  8. Freundlich and Langmuir adsorption isotherms and kinetics for the removal of Tartrazine from aqueous solutions using hen feathers

    Energy Technology Data Exchange (ETDEWEB)

    Mittal, Alok [Department of Applied Chemistry, Maulana Azad National Institute of Technology, Bhopal, 462 007 MP (India)]. E-mail: aljymittal@yahoo.co.in; Kurup, Lisha [Department of Applied Chemistry, Maulana Azad National Institute of Technology, Bhopal, 462 007 MP (India); Mittal, Jyoti [Department of Applied Chemistry, Maulana Azad National Institute of Technology, Bhopal, 462 007 MP (India)

    2007-07-19

    Tartrazine, a yellow menace, is widely being used in cosmetics, foodstuffs, medicines and textile. It is carcinogenic and also catalyzes allergic problems. In the present work the ability to remove Tartrazine from aqueous solutions has been studied using waste material-hen feathers, as adsorbent. Effects of pH, concentration of the dye, temperature and adsorbent dosage have been studied. Equilibrium isotherms for the adsorption of the dye were measured experimentally. Results were analyzed by the Freundlich and Langmuir equation at different temperatures and determined the characteristic parameters for each adsorption isotherm. The adsorption process has been found endothermic in nature and thermodynamic parameters, Gibb's free energy ({delta}G{sup o}), change in enthalpy ({delta}H{sup o}) and change in entropy ({delta}S{sup o}) have been calculated. The paper also includes results on the kinetic measurements of adsorption of the dye on hen feathers at different temperatures. By rate expression and treatment of data it has been established that the adsorption of Tartrazine over hen feathers follows a first-order kinetics and a film diffusion mechanism operates at all the temperatures.

  9. Freundlich and Langmuir adsorption isotherms and kinetics for the removal of Tartrazine from aqueous solutions using hen feathers.

    Science.gov (United States)

    Mittal, Alok; Kurup, Lisha; Mittal, Jyoti

    2007-07-19

    Tartrazine, a yellow menace, is widely being used in cosmetics, foodstuffs, medicines and textile. It is carcinogenic and also catalyzes allergic problems. In the present work the ability to remove Tartrazine from aqueous solutions has been studied using waste material-hen feathers, as adsorbent. Effects of pH, concentration of the dye, temperature and adsorbent dosage have been studied. Equilibrium isotherms for the adsorption of the dye were measured experimentally. Results were analyzed by the Freundlich and Langmuir equation at different temperatures and determined the characteristic parameters for each adsorption isotherm. The adsorption process has been found endothermic in nature and thermodynamic parameters, Gibb's free energy (DeltaG degrees), change in enthalpy (DeltaH degrees) and change in entropy (DeltaS degrees) have been calculated. The paper also includes results on the kinetic measurements of adsorption of the dye on hen feathers at different temperatures. By rate expression and treatment of data it has been established that the adsorption of Tartrazine over hen feathers follows a first-order kinetics and a film diffusion mechanism operates at all the temperatures.

  10. The relative cueing power of F0 and duration in German prominence perception

    DEFF Research Database (Denmark)

    Niebuhr, Oliver; Winkler, Jana

    2017-01-01

    hierarchy further by putting numbers on the interplay of duration and F0. German listeners indirectly judged through lexical identification the relative prominence levels of two neighboring syllables. Results show that an increase in F0 of between 0.49 and 0.76 st is required to outweigh the prominence...... effect of a 30% increase in duration of a neighboring syllable. These numbers are fairly stable across a large range of absolute F0 and duration levels and hence useful in speech technology....

  11. DIRECT DETECTION OF THE HELICAL MAGNETIC FIELD GEOMETRY FROM 3D RECONSTRUCTION OF PROMINENCE KNOT TRAJECTORIES

    Energy Technology Data Exchange (ETDEWEB)

    Zapiór, Maciej; Martinez-Gómez, David, E-mail: zapior.maciek@gmail.com [Physics Department, University of the Balearic Islands, Cra. de Valldemossa, km 7.5. Palma (Illes Balears), E-07122 (Spain)

    2016-02-01

    Based on the data collected by the Vacuum Tower Telescope located in the Teide Observatory in the Canary Islands, we analyzed the three-dimensional (3D) motion of so-called knots in a solar prominence of 2014 June 9. Trajectories of seven knots were reconstructed, giving information of the 3D geometry of the magnetic field. Helical motion was detected. From the equipartition principle, we estimated the lower limit of the magnetic field in the prominence to ≈1–3 G and from the Ampère’s law the lower limit of the electric current to ≈1.2 × 10{sup 9} A.

  12. Direct Detection of the Helical Magnetic Field Geometry from 3D Reconstruction of Prominence Knot Trajectories

    Science.gov (United States)

    Zapiór, Maciej; Martínez-Gómez, David

    2016-02-01

    Based on the data collected by the Vacuum Tower Telescope located in the Teide Observatory in the Canary Islands, we analyzed the three-dimensional (3D) motion of so-called knots in a solar prominence of 2014 June 9. Trajectories of seven knots were reconstructed, giving information of the 3D geometry of the magnetic field. Helical motion was detected. From the equipartition principle, we estimated the lower limit of the magnetic field in the prominence to ≈1-3 G and from the Ampère’s law the lower limit of the electric current to ≈1.2 × 109 A.

  13. Use of feathers to assess polychlorinated biphenyl and organochlorine pesticide exposure in top predatory bird species of Pakistan

    International Nuclear Information System (INIS)

    Abbasi, Naeem Akhtar; Eulaers, Igor; Jaspers, Veerle L.B.; Chaudhry, Muhammad Jamshed Iqbal; Frantz, Adrien; Ambus, Per Lennart; Covaci, Adrian; Malik, Riffat Naseem

    2016-01-01

    Little is known about the levels of organochlorines (OCs) in predatory bird species from Asia or the factors governing their concentrations. This study is the first report on concentrations of polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) in predatory birds of Pakistan. The concentrations of PCBs and OCPs were investigated using tail feathers of ten different species of predatory birds. In addition, concentration differences among body, tail, primary and secondary feathers were investigated for six individuals of black kite (Milvus migrans). Ranges of concentrations were highest for dichlorodiphenyldichloroethylene (p,p′-DDE: 0.11–2163 ng g − 1 dry wt.) followed by dichlorodiphenyltrichloroethane (p,p′-DDT: 0.36–345 ng g − 1 dry wt.), hexachlorobenzene (HCB: 0.02–34 ng g − 1 dry wt.), ∑ PCBs (0.03–16 ng g − 1 dry wt.) and trans-nonachlor (TN; 0.01–0.13 ng g − 1 dry wt.). CB 118, 153, 138, and 180 along with p,p′-DDE were found as the most prevalent compounds. ∑ PCBs and ∑ DDTs were significantly different among species (both p < 0.01) and omnivorous, scavengers, carnivorous and piscivorous trophic guilds (all p < 0.03). Only ∑ PCBs were significantly differentamong different families of birds (p < 0.01). Values of stable isotopes (δ 13 C and δ 15 N) differed significantly (all p < 0.01) among species, families, trophic guilds as well as terrestrial and aquatic habitat but not between nocturnal and diurnal predators (p = 0.22 for δ 13 C; p = 0.50 for δ 15 N). Concentrations of ∑ PCBs, ∑ DDTs and trans-nonachlor, but not HCB (p = 0.86), were significantly different among different feather types (all p < 0.01). Trophic and taxonomic affiliation as well as dietary carbon sources (δ 13 C) for species were identified as the variables best explaining the observed variation in exposure to the studied compounds. The significance of contributing factors responsible for OC contamination differences in

  14. Use of feathers to assess polychlorinated biphenyl and organochlorine pesticide exposure in top predatory bird species of Pakistan

    Energy Technology Data Exchange (ETDEWEB)

    Abbasi, Naeem Akhtar [Environmental Biology and Ecotoxicology Laboratory, Department of Environmental Sciences, Faculty of Biological Sciences, Quaid-i-Azam University, Islamabad 45320 (Pakistan); Eulaers, Igor [Department of Bioscience, Aarhus University, Frederiksborgvej 399, P.O. Box 358, 4000 Roskilde (Denmark); Jaspers, Veerle L.B., E-mail: veerle.jaspers@ntnu.no [Environmental Toxicology, Department of Biology, Norwegian University of Science and Technology (NTNU), Trondheim (Norway); Chaudhry, Muhammad Jamshed Iqbal [Environmental Biology and Ecotoxicology Laboratory, Department of Environmental Sciences, Faculty of Biological Sciences, Quaid-i-Azam University, Islamabad 45320 (Pakistan); WWF-Pakistan, Ferozpur Road, PO Box 5180, Lahore 54600 (Pakistan); Frantz, Adrien [Sorbonne Universités, UPMC Univ Paris 06, UPEC, Paris 7, CNRS, INRA, IRD, Institut d' Ecologie et des Sciences de l' Environnement de Paris, F-75005 Paris (France); Ambus, Per Lennart [Center for Permafrost, Department of Geosciences and Natural Resource Management, University of Copenhagen, Øster Voldgade 10, 1350 København K (Denmark); Covaci, Adrian [Toxicological Centre, University of Antwerp, Universiteitsplein 1, 2610 Wilrijk (Belgium); Malik, Riffat Naseem, E-mail: r_n_malik2000@yahoo.co.uk [Environmental Biology and Ecotoxicology Laboratory, Department of Environmental Sciences, Faculty of Biological Sciences, Quaid-i-Azam University, Islamabad 45320 (Pakistan)

    2016-11-01

    Little is known about the levels of organochlorines (OCs) in predatory bird species from Asia or the factors governing their concentrations. This study is the first report on concentrations of polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) in predatory birds of Pakistan. The concentrations of PCBs and OCPs were investigated using tail feathers of ten different species of predatory birds. In addition, concentration differences among body, tail, primary and secondary feathers were investigated for six individuals of black kite (Milvus migrans). Ranges of concentrations were highest for dichlorodiphenyldichloroethylene (p,p′-DDE: 0.11–2163 ng g{sup −} {sup 1} dry wt.) followed by dichlorodiphenyltrichloroethane (p,p′-DDT: 0.36–345 ng g{sup −} {sup 1} dry wt.), hexachlorobenzene (HCB: 0.02–34 ng g{sup −} {sup 1} dry wt.), ∑ PCBs (0.03–16 ng g{sup −} {sup 1} dry wt.) and trans-nonachlor (TN; 0.01–0.13 ng g{sup −} {sup 1} dry wt.). CB 118, 153, 138, and 180 along with p,p′-DDE were found as the most prevalent compounds. ∑ PCBs and ∑ DDTs were significantly different among species (both p < 0.01) and omnivorous, scavengers, carnivorous and piscivorous trophic guilds (all p < 0.03). Only ∑ PCBs were significantly differentamong different families of birds (p < 0.01). Values of stable isotopes (δ{sup 13}C and δ{sup 15}N) differed significantly (all p < 0.01) among species, families, trophic guilds as well as terrestrial and aquatic habitat but not between nocturnal and diurnal predators (p = 0.22 for δ{sup 13}C; p = 0.50 for δ{sup 15}N). Concentrations of ∑ PCBs, ∑ DDTs and trans-nonachlor, but not HCB (p = 0.86), were significantly different among different feather types (all p < 0.01). Trophic and taxonomic affiliation as well as dietary carbon sources (δ{sup 13}C) for species were identified as the variables best explaining the observed variation in exposure to the studied compounds. The significance of

  15. F0-based rhythm effects on the perception of local syllable prominence

    DEFF Research Database (Denmark)

    Niebuhr, Oliver

    2009-01-01

    of the global rhythmic context with regard to both the prominence and the F(0) patterns. Two conclusions were drawn on this basis. First, listeners use speech rhythm to predict the perceptual properties of syllables, which is in line with the guide function that speech rhythm is assumed to have in German...

  16. Synthetic Hydrogen Spectra of Oscillating Prominence Slabs Immersed in the Solar Corona

    Czech Academy of Sciences Publication Activity Database

    Zapiór, Maciej; Oliver, R.; Ballester, J.L.; Heinzel, Petr

    2016-01-01

    Roč. 827, č. 2 (2016), 131/1-131/7 ISSN 0004-637X R&D Projects: GA ČR(CZ) GA16-18495S Institutional support: RVO:67985815 Keywords : Sun * filaments * prominences Subject RIV: BN - Astronomy, Celestial Mechanics, Astrophysics Impact factor: 5.533, year: 2016

  17. Class of analytic solutions for the thermally balanced magnetostatic prominence sheet

    International Nuclear Information System (INIS)

    Low, B.C.; Wu, S.T.

    1981-01-01

    This is a theoretical study of the nonlinear interplay between magnetostatic equilibrium and energy balance in a Kippenhahn-Schlueter type prominence sheet. The basic effects are illustrated explicitly with an analytic model in which a radiative loss proportional to rho 2 T balances against wave heating proportional to rho, with thermal conduction confined along magnetic field lines, where rho and T denote the plasma density and temperature, respectively. The particular choices of heat sink and source enable us to integrate the governing equations exactly while they are of the basic mathematical forms to simulate radiative loss in an optically thin plasma which is heated by wave dissipation. The steady solutions exhibit three different basic behaviors, characterized by the total wave heating in the prominence sheet being more than, equal to, or less than the total radiative loss. It is the compaction of the plasma along the field lines under its own weight combined with the effects of energy transport that determines which of the three basic behaviors obtains in a particular situation. The implications of the steady solutions for the formation of prominences are discussed. The exact solutions presented do not support the conclusion of Milne, Priest, and Roberts that there is an upper bound on the plasma beta for an equilibrium of the Kippenhahn-Schlueter prominence

  18. From Wilhelm von Humboldt to Hitler-are prominent people more prone to have Parkinson's disease?

    Science.gov (United States)

    Horowski; Horowski; Calne; Calne

    2000-10-01

    We describe Parkinsonism in prominent people, where Wilhelm von Humboldt and Adolf Hitler provide just two spectacular, opposing examples. In both of them, there is little if any evidence that the disease did influence their life ambitions, methods of achieving them or cognitive function in general. Thus, Hitler's Parkinsonism should remain a 'footnote' to history, and historians should acknowledge that in his last years, his trembling, his curbed posture, his slow walking, mask-like face and low voice did not indicate remorse, fear or depression as a consequence of his crimes, but were mere expressions of his disease whic