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61.
62.
Danillo S Silva Susana SR Milhomem Julio C Pieczarka Cleusa Y Nagamachi 《BMC genetics》2009,10(1):1-8
Background
Previous studies suggested that multiple domestication events in South and South-East Asia (Yunnan and surrounding areas) and India have led to the genesis of modern domestic chickens. Ha Giang province is a northern Vietnamese region, where local chickens, such as the H'mong breed, and wild junglefowl coexist. The assumption was made that hybridisation between wild junglefowl and Ha Giang chickens may have occurred and led to the high genetic diversity previously observed. The objectives of this study were i) to clarify the genetic structure of the chicken population within the Ha Giang province and ii) to give evidence of admixture with G. gallus. A large survey of the molecular polymorphism for 18 microsatellite markers was conducted on 1082 chickens from 30 communes of the Ha Giang province (HG chickens). This dataset was combined with a previous dataset of Asian breeds, commercial lines and samples of Red junglefowl from Thailand and Vietnam (Ha Noï). Measurements of genetic diversity were estimated both within-population and between populations, and a step-by-step Bayesian approach was performed on the global data set.Results
The highest value for expected heterozygosity (> 0.60) was found in HG chickens and in the wild junglefowl populations from Thailand. HG chickens exhibited the highest allelic richness (mean A = 2.9). No significant genetic subdivisions of the chicken population within the Ha Giang province were found. As compared to other breeds, HG chickens clustered with wild populations. Furthermore, the neighbornet tree and the Bayesian clustering analysis showed that chickens from 4 communes were closely related to the wild ones and showed an admixture pattern.Conclusion
In the absence of any population structuring within the province, the H'mong chicken, identified from its black phenotype, shared a common gene pool with other chickens from the Ha Giang population. The large number of alleles shared exclusively between Ha Giang chickens and junglefowl, as well as the results of a Bayesian clustering analysis, suggest that gene flow has been taking place from junglefowl to Ha Giang chickens. 相似文献63.
64.
Joshua B. Fisher Munish Sikka Stephen Sitch Philippe Ciais Benjamin Poulter David Galbraith Jung-Eun Lee Chris Huntingford Nicolas Viovy Ning Zeng Anders Ahlstr?m Mark R. Lomas Peter E. Levy Christian Frankenberg Sassan Saatchi Yadvinder Malhi 《Philosophical transactions of the Royal Society of London. Series B, Biological sciences》2013,368(1625)
The African humid tropical biome constitutes the second largest rainforest region, significantly impacts global carbon cycling and climate, and has undergone major changes in functioning owing to climate and land-use change over the past century. We assess changes and trends in CO2 fluxes from 1901 to 2010 using nine land surface models forced with common driving data, and depict the inter-model variability as the uncertainty in fluxes. The biome is estimated to be a natural (no disturbance) net carbon sink (−0.02 kg C m−2 yr−1 or −0.04 Pg C yr−1, p < 0.05) with increasing strength fourfold in the second half of the century. The models were in close agreement on net CO2 flux at the beginning of the century (σ1901 = 0.02 kg C m−2 yr−1), but diverged exponentially throughout the century (σ2010 = 0.03 kg C m−2 yr−1). The increasing uncertainty is due to differences in sensitivity to increasing atmospheric CO2, but not increasing water stress, despite a decrease in precipitation and increase in air temperature. However, the largest uncertainties were associated with the most extreme drought events of the century. These results highlight the need to constrain modelled CO2 fluxes with increasing atmospheric CO2 concentrations and extreme climatic events, as the uncertainties will only amplify in the next century. 相似文献
65.
David Lindenmayer Emmo Willinck Mason Crane Damian Michael Sachiko Okada Chris Cumming Kylie Durant Judy Frankenberg 《Ecological Management & Restoration》2013,14(2):80-92
Native vegetation restoration and conservation works have been ongoing for three decades in the South West Slopes Bioregion of NSW's Murray Catchment. Monitoring of extensive areas of protected remnants and revegetation undertaken through a major partnership between ANU researchers and the Murray CMA shows early benefits of restoration efforts to biodiversity and helps to refine future efforts. 相似文献
66.
Renfree MB Papenfuss AT Deakin JE Lindsay J Heider T Belov K Rens W Waters PD Pharo EA Shaw G Wong ES Lefèvre CM Nicholas KR Kuroki Y Wakefield MJ Zenger KR Wang C Ferguson-Smith M Nicholas FW Hickford D Yu H Short KR Siddle HV Frankenberg SR Chew KY Menzies BR Stringer JM Suzuki S Hore TA Delbridge ML Patel HR Mohammadi A Schneider NY Hu Y O'Hara W Al Nadaf S Wu C Feng ZP Cocks BG Wang J Flicek P Searle SM Fairley S Beal K Herrero J Carone DM Suzuki Y Sugano S Toyoda A Sakaki Y Kondo S 《Genome biology》2011,12(8):R81
67.
68.
The fundamental assumption implicit in the use of the atomic bomb survivor data to derive risk estimates is that the gamma rays of Hiroshima and Nagasaki are considered to have biological efficiencies equal to those of other low-LET radiations up to 10 keV/microm, including mammography X rays. Microdosimetric and radiobiological data contradict this assumption. It is therefore of scientific and public interest to evaluate the efficiency of mammography X rays (25-30 kVp) to induce cancer. In this study, the efficiency of mammography X rays relative to 200 kVp X rays to induce neoplastic cell transformation was evaluated using cells of a human hybrid cell line (CGL1). For both radiations, a linear-quadratic dose-effect relationship was observed for neoplastic transformation of CGL1 cells; there was a strong linear component for the 29 kVp X rays. The RBE(M) of mammography X rays relative to 200 kVp X rays was determined to be about 4 for doses < or = 0.5 Gy. A comparison of the electron fluences for both X rays provides strong evidence that electrons with energies of < or = 15 keV can induce neoplastic transformation of CGL1 cells. Both the data available in the literature and the results of the present study strongly suggest an increase of RBE(M) for carcinogenesis in animals, neoplastic cell transformation, and clastogenic effects with decreasing photon energy or increasing LET to an RBE(M) approximately 8 for mammography X rays relative to 60Co gamma rays. 相似文献
69.
70.
Winstedt L Frankenberg L Hederstedt L von Wachenfeldt C 《Journal of bacteriology》2000,182(13):3863-3866
We have cloned an Enterococcus faecalis gene cluster, cydABCD, which when expressed in Bacillus subtilis results in a functional cytochrome bd terminal oxidase. Our results indicate that E. faecalis V583 cells have the capacity of aerobic respiration when grown in the presence of heme. 相似文献