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Sonia M. Hernandez Valerie E. Peters P. Logan Weygandt Carlos Jimenez Pedro Villegas Barry O’Connor Michael J. Yabsley Maricarmen Garcia Sylva M. Riblet C. Ron Carroll 《EcoHealth》2013,10(2):145-158
Shade-grown coffee plantations are often promoted as a conservation strategy for wild birds. However, these agro-ecosystems are actively managed for food production, which may alter bird behaviors or interactions that could change bird health, compared to natural forest. To examine whether there is a difference between the health parameters of wild birds inhabiting shade-grown coffee plantations and natural forest, we evaluated birds in Costa Rica for (1) their general body condition, (2) antibodies to pathogens, (paramyxovirus and Mycoplasma spp.), and (3) the prevalence and diversity of endo-, ecto-, and hemoparasites. We measured exposure to Mycoplasma spp. and paramyxovirus because these are pathogens that could have been introduced with domestic poultry, one mechanism by which these landscapes could be detrimental to wild birds. We captured 1,561 birds representing 75 species. Although seasonal factors influenced body condition, we did not find bird general body condition to be different. A total of 556 birds of 31 species were tested for antibodies against paramyxovirus-1. Of these, five birds tested positive, four of which were from shade coffee. Out of 461 other tests for pathogens (for antibodies and nucleotide detection), none were positive. Pterolichus obtusus, the feather mite of chickens, was found on 15 birds representing two species and all were from shade-coffee plantations. Larvated eggs of Syngamus trachea, a nematode typically associated with chickens, were found in four birds captured in shade coffee and one captured in forest. For hemoparasites, a total of 1,121 blood smears from 68 bird species were examined, and only one species showed a higher prevalence of infection in shade coffee. Our results indicate that shade-coffee plantations do not pose a significant health risk to forest birds, but at least two groups of pathogens may deserve further attention: Haemoproteus spp. and the diversity and identity of endoparasites. 相似文献
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Resolving the polymorphism-in-probe problem is critical for correct interpretation of expression QTL studies 总被引:1,自引:0,他引:1
Adaikalavan Ramasamy Daniah Trabzuni J. Raphael Gibbs Allissa Dillman Dena G. Hernandez Sampath Arepalli Robert Walker Colin Smith Gigaloluwa Peter Ilori Andrey A. Shabalin Yun Li Andrew B. Singleton Mark R. Cookson for NABEC John Hardy for UKBEC Mina Ryten Michael E. Weale 《Nucleic acids research》2013,41(7):e88
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Jose Itzigsohn Carlos Dore Cabral Esther Hernandez Medina Obed Vazquez 《Ethnic and racial studies》2013,36(2):316-339
This article maps the structure for understanding the Dominican transnational field. By transnational field we refer to a web of linkages that affects the lives of Dominicans in their places of residence in every social field. We find that social boundaries of the nation do not coincide with political ones and the degree of participation in transnational exchanges varies. We suggest that the structure of the transnational social field is better understood by establishing and defining broad and narrow transnational social practices. 相似文献
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Julio Alfonso Cruz Medina Jessica Enriquez Farias Andrés Cruz Hernández Rocio Garcia Martinez Sara Solis Valdes Gilberto Hernandez Silva 《Geomicrobiology journal》2013,30(5):454-461
Metal phytoextraction assisted by bacteria plays an important role in bioremediation systems. In this work, mercury-resistant bacterial strains were isolated from soils with high levels of mercury (San Joaquin, Queretaro State, Mexico) and identified as Bacillus sp. based on the 16S rDNA gene sequence analysis. The bacterial strains were found to exhibit different multiple mercury-resistance and carbon source utilization characteristics. The mercury reduction ability was tested through a volatilization assay. The bacterial isolates were also evaluated for their ability to promote growth and mercury uptake in tomato plants. In a roll towel assay, the maximum vigor index of tomato plants was obtained with the inoculation of Bacillus sp. A2, A12, B11, B15 and C1, while in a pot assay, the maximum vigor index was obtained with the inoculation of Bacillus sp. A6, A7 and B20, compared with un-inoculated controls in the presence of HgCl2. Maximum Hg accumulation in the roots and shoots of tomato plants was obtained only with Bacillus sp. A7 in the roll towel assay, whereas in the pot assay, maximum accumulation was obtained with Bacillus sp. A12 compared with un-inoculated controls. Our results show that mercury accumulation in tissue is enhanced by these plant growth promoting bacterial strains, which recommends their possible use as microbe-assisted phytoremediation systems in mercury-polluted soils. 相似文献
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Teresa Braunwald Lisa Schwemmlein Simone Graeff-Hönninger William Todd French Rafael Hernandez William E. Holmes Wilhelm Claupein 《Applied microbiology and biotechnology》2013,97(14):6581-6588
Due to the increasing demand for sustainable biofuels, microbial oils as feedstock for the transesterification into biodiesel have gained scientific and commercial interest. Also, microbial carotenoids have a considerable market potential as natural colorants. The carbon to nitrogen (C/N) ratio of the respective cultivation media is one of the most important parameters that influence the production of microbial lipids and carotenoids. Thus, in the present experiment, the influence of different C/N ratios, initial glucose loadings, and ammonium concentrations of the cultivation medium on microbial cell growth and lipid and carotenoid production by the oleaginous red yeast Rhodotorula glutinis has been assessed. As a general trend, both lipid and carotenoid production increased at high C/N ratios. It was shown that not only the final C/N ratio but also the respectively applied initial carbon and nitrogen contents influenced the observed parameters. The lipid yield was not affected by different ammonium contents, while the carotenoid production significantly decreased both at low and high levels of ammonium supply. A glucose-based increase from C/N 70 to 120 did not lead to an increased lipid production, while carotenoid synthesis was positively affected. Generally, it can be asserted that lipid and carotenoid synthesis are stimulated at higher C/N ratios. 相似文献
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