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Alexander L. Bond 《Environmental pollution (Barking, Essex : 1987)》2010,158(5):1182-1184
Stable isotopes of carbon (δ13C) and nitrogen (δ15N) are used frequently in ecotoxicological investigations of birds to relate contaminant levels to trophic position (δ15N) or foraging location (δ13C) and many researchers using avian feathers in such investigations use δ13C or δ15N as a predictor of contaminant concentrations. Contaminants, especially mercury, however, are integrated into feathers over different time periods than are stable isotopes, resulting in spurious relationships that have no biological meaning. I show the fundamental principles behind the conclusion that relating δ13C or δ15N to contaminant concentrations in feathers is not appropriate in light of the number of recent studies that have employed this approach, and make recommendations for those wishing to investigate the relationship between contaminants and stable isotope ratios. 相似文献
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Hien V. Dao Lauren A. Maher Lawrence N. Ngeh Stephen W. Bigger John D. Orbell Margaret Healy Rosalind Jessop Peter Dann 《Environmental Chemistry Letters》2006,4(2):111-113
A previously reported acute temperature dependency for the effective removal of tarry residue from feather clusters, utilising magnetic particles, has also been demonstrated to occur for the plumage of whole birds, whereby a maximum removal of up to 96% may be achieved. The experimental design allows an approximate equilibrium constant, for the distribution of contaminant between the residue and the magnetic particles, to be estimated at each temperature. This allows the thermodynamics of the process to be examined via application of the van't Hoff equation, suggesting an explanation for the phenomenon. 相似文献
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John D. Orbell Hien Van Dao Lawrence N. Ngeh Stephen W. Bigger Margaret Healy Rosalind Jessop Peter Dann 《Environmental Chemistry Letters》2005,3(1):25-27
We have conducted temperature-dependent studies on the removal of a solidified tarry residue from feathers using magnetic particles. These studies demonstrate an acute temperature dependency whereby no contaminant at all is removed below a certain temperature but, at and above this temperature, the removal rapidly approaches 100%. Significantly, this temperature is well below the temperature at which the tarry residue becomes a flowing liquid. This demonstrates that it is possible for magnetic cleansing to remove up to 100% of tarry residue from feathers under temperature conditions that would be benign to a bird. 相似文献
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The structure and properties of chicken feather barbs makes them unique fibers preferable for several applications. The presence
of hollow honeycomb structures, their low density, high flexibility and possible structural interaction with other fibers
when made into products such as textiles provides them unique properties unlike any other natural or synthetic fibers. No
literature is available on the physical structure and tensile properties of chicken feather barbs. In this study, we report
the physical and morphological structure and the properties of chicken feather barbs for potential use as natural protein
fibers. The morphological structure of chicken feather barbs is similar to that of the rachis but the physical structure of
the protein crystals in chicken feather barbs is different than that reported for feather rachis keratin. The tensile properties
of barbs in terms of their strength and modulus are similar but the elongation is lower than that of wool. Using the cheap
and abundant feathers as protein fibers will conserve the energy, benefit the environment and also make the fiber industry
more sustainable 相似文献
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Vyas NB Spann JW Hulse CS Gentry S Borges SL 《Environmental monitoring and assessment》2007,133(1-3):209-214
The US Environmental Protection Agency conducts risk assessments of insecticide applications to wild birds using a model that
is limited to the dietary route of exposure. However, free-flying birds are also exposed to insecticides via the inhalation
and dermal routes. We measured azinphos-methyl residues on the skin plus feathers and the feet of brown-headed cowbirds (Molothrus ater) in order to quantify dermal exposure to songbirds that entered and inhabited an apple (Malus x domestica) orchard following an insecticide application. Exposure to azinphos-methyl was measured by sampling birds from an aviary
that was built around an apple tree. Birds sampled at 36 h and 7-day post-application were placed in the aviary within 1 h
after the application whereas birds exposed for 3 days were released into the aviary 4-day post-application. Residues on vegetation
and soil were also measured. Azinphos-methyl residues were detected from the skin plus feathers and the feet from all exposure
periods. Our results underscore the importance of incorporating dermal exposure into avian pesticide risk assessments. 相似文献
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