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Calculations of population differentiation based on GST and D: forget GST but not all of statistics!
GABRIELE GERLACH ALEXANDER JUETERBOCK PHILIPP KRAEMER JANA DEPPERMANN PETER HARMAND 《Molecular ecology》2010,19(18):3845-3852
G ST‐values and its relatives (FST) belong to the most used parameters to define genetic differences between populations. Originally, they were developed for allozymes with very low number of alleles. Using highly polymorphic microsatellite markers it was often puzzling that GST‐values were very low but statistically significant. In their papers, Jost (2008) and Hedrick (2005) explained that GST‐values do not show genetic differentiation, and Jost suggested calculating D‐values instead. Theoretical mathematical considerations are often difficult to follow; therefore, we chose an applied approach comparing two artificial populations with different number of alleles at equal frequencies and known genetic divergence. Our results show that even for more than one allele per population GST‐values do not calculate population differentiation correctly; in contrast, D‐values do reflect the genetic differentiation indicating that data based on GST‐values need to be re‐evaluated. In our approach, statistical evaluations remained similar. We provide information about the impact of different sample sizes on D‐values in relation to number of alleles and genetic divergence. 相似文献
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ALEXANDER GILLESPIE 《Ocean Development & International Law》2013,44(3-4):349-367
The final area of work that needs to be completed by the International Whaling Commission (IWC) before the moratorium on commercial whaling may be lifted is the Revised Management Scheme (RMS). The key issue stalling conclusion of the RMS is the failure to agree on the details of a suitable inspection, observation, and compliance regime. This contribution looks at the negotiations respecting the development of a suitable inspection, observation, and compliance regime. 相似文献
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P.J. HAYWARD F.L.S. J. S. RYLAND F.L.S. 《Zoological Journal of the Linnean Society》1996,117(1):103-112
Five British species of Reteporella Busk, 1884 are described and figured. A neotype specimen is selected for R. beaniana (King), and R. incognita sp. nov. is described, and distinguished from R. couchii (Hincks). 相似文献
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HANSEN ALEXANDER P.; YONEYAMA TADAKATSU; KOUCHI HIROSHI 《Journal of experimental botany》1992,43(1):1-7
A comparison between two hydroponically-grown soybean genotypes(Glycine max [L.] Merr.) cv. Bragg and the supernodulating mutantnts 1007 was made in terms of dry matter accumulation, carbon,nitrogen, and mineral element distribution, 15N natural abundanceand the effect of short-term treatment with 4·0 mol m3KNO3 on nitrogenase activity and respiration. Differences weremost pronounced in nodule dry weight and plant nitrogen content,both of which were recorded to be substantially elevated inthe mutant. Mineral element concentrations in different plantparts proved to be rather similar with the exception of Ca,found to be lower in leaves of the mutant, and Mn concentrationswhich were twice as high in roots of nts 1007. The values of15N natural abundance showed that both genotypes were equallydependent on nitrogen fixation when nitrate was absent. Theresults of the acetylene reduction assays indicated similarspecific nodule activity, while on a per plant basis nitrogenaseactivity of the mutant proved to be more than twice the amountof Bragg. This effect was also reflected in higher nodule respirationwhile root respiration remained below that of Bragg. Nitrate induced a substantial reduction in nitrogenase activitynot only in Bragg, but also in nts 1007. Nodule respiratoryactivity of Bragg was reduced by nitrate from 1·27 to0·34 mg C h1 plant1. In nts 1007 correspondingvalues were 2·70 to 1·52 mg C h1 plant1.Starch concentration in nodules was decreased in both genotypes,but nevertheless remained higher in nts 1007. Values for solublesugars in nodules even increased in the mutant in response tonitrate while the same treatment caused a reduction in Bragg.The data indicate that nitrogenase activities of Bragg and nts1007 are equally sensitive to short-term application of nitrate. Key words: Glycine max, C and N distribution, nitrate, root respiration, 15N natural abundance 相似文献
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