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A total of 15 microsatellite primers pairs were developed for the Australian small‐eyed snake Rhinoplocephalus nigrescens. Five primers were used to screen 93 individuals of R. nigrescens and were also tested against eight species of the closely related genus Suta. Allelic diversity in R. nigrescens was high in three loci (12–27) and there was high heterozygosity (0.58–0.82). Observed heterozygosity did not deviate from Hardy–Weinberg expectations for the five loci tested. These primers will be useful in studies of population genetics and mating systems of small‐eyed snakes and related species.  相似文献   
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The carbon balance of a winter wheat crop in Lonzée, Belgium, was assessed from measurements carried out at different spatial and temporal scales between November 2004 and August 2005. From eddy covariance measurements, the net ecosystem exchange was found to be ?0.63 kg C m?2 and resulted from the difference between gross primary productivity (GPP) (?1.58 kg C m?2) and total ecosystem respiration (TER) (0.95 kg C m?2). The impact of the u* threshold value on these fluxes was assessed and found to be very small. GPP assessment was partially validated by comparison with an estimation scaled up from leaf scale assimilation measurements. Soil respiration (SR), extrapolated from chamber measurements, was 0.52 kg C m?2. Net primary productivity, assessed from crop sampling, was ?0.83 kg C m?2. By combining these fluxes, the autotrophic and heterotrophic components of respiration were deduced. Autotrophic respiration dominated both TER and SR. The evolution of these fluxes was analysed in relation to wheat development.  相似文献   
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We report the details and characteristics of a total of 44 novel microsatelllite loci for Bombus spp. Most of them are highly polymorphic in Bombus terrestris, and a high degree of polymorphism is also found where these primers have been tested in 10 other bumblebee species. These markers will therefore be useful for the genetic study of this group.  相似文献   
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Even when a field experiment has been designed with care, subsequent examination of the plot values may reveal additional unforeseen trends. In this paper we examine data from a barley pathology field trial and show that additive models provide a flexible representation of environmental trends, in one or two dimensions. Such models smooth out noise in the observed data, rather than fit an equation specified in advance. This approach tends to increase the precision of treatment comparisons relative to a classical analysis of variance. We recommend the use of residual plots to explore experimental data for underlying trends, and additive models to display these trends and estimate treatment effects.  相似文献   
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Synthesis of Acetylcholine in the Absence of Exogenous Choline   总被引:3,自引:0,他引:3  
THE breakdown of acetyl-CoA during incubation with rat brain homogenate or sections of rat nervous tissue in the absence of choline has been reported by Kasa, Mann and Hebb1. They found that the conversion of 14C-acetyl-CoA to 14C-acetate thus incubated was considerably depressed by 10?4 eserine or 10?5 M di-isopropylfluorophosphate (DFP) but further depressed by 10?3 M DFP. Experiments in our laboratories lead us to offer an explanation for that part of the breakdown inhibited by eserine or low concentrations of DFP.  相似文献   
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