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??????????????С????????У??????Ч????????????????????????????????μ??????С????????????????????彻??????L??????????????????????????????????????????????????????????????????????????Ч??????? 相似文献
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The estimation of genetic parameters has played an important role in animal selective breeding for growth traits.Recently studies show that molecular markers can be incorporated into genetic evaluations. In order to improve the performance of an incomplete pedigree(i.e, only parents are known) in the genetic evaluations, 12 microsatellite markers have been applied in the estimation of the genetic parameters for body weight in a farmed population(n=1 890) of juvenile turbot(Scophthalmus maximus L.). A new relatedness called parental molecular relatedness(PMR) is estimated based on results of genotyping of 48 parents(31 males, 17 females) with microsatellites markers. The feasibility of PMR in estimation of genetic parameters is verified by comparison with pedigree related(PR) which is obtained from a complete pedigree. The results demonstrate that a high correlation(0.872) between them is found. Heritabilities are estimated using the PMR(0.52±0.13) and PR(0.55±0.22) with the same animal model. A cross-validation shows that the predictive abilities of models using the PMR and the PR are identical(0.81). From that, a conclusion can be made that PMR and PR predicted genetic values equally well in a population of juvenile turbot. Therefore PMR can be applied as an alternative of the PR when only parents are known. However, for a better performance, more markers and more families should be included in a further study. 相似文献
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The geophysical model function (GMF) describes the relationship between backscattering and sea surface wind, so that wind vec- tors can be retrieved from backscattering measurement. The GMF plays an important role in ocean wind vector retrievals, its performance will directly influence the accuracy of the retrieved wind vector. Neural network (NN) approach is used to develop a unified GMF for C-band and Ku-band (NN-GMF). Empirical GMF CMOIM and QSCAT-1 are used to generate the simulated training data-set, and Gaussian noise at a signal noise ratio of 30 dB is added to the data-set to simulate the noise in the backscat- tering measurement. The NN-GMF employs radio frequency as an additional parameter, so it can be applied for both C-band and Ku-band. Analyses show that the %predicted by the NN-GMF is comparable with the σpredicted by CMOIM and QSCAT-1. Also the wind vectors retrieved from the NN-GMF and empirical GMF CMOIM and QSCAT-1 are comparable, indicating that the NN-GMF is as effective as the empirical GMF, and has the advantages of the universal form. 相似文献
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X波段雷达图像提取海洋表面风场 总被引:1,自引:0,他引:1
船用X波段导航雷达海杂波图像中包含有丰富的海浪、海面流和风场等环境信息。阵风的运动在滤波后的雷达图像序列中是可见的,根据分析阵风的运动,用基于运动估计技术的光流方法从阵风的运动中测定风矢量。文章主要分析了小麦岛海域岸基试验的海杂波数据,将用雷达图像序列提取的风矢量和现场风速仪、风向标测得的风矢量做了比较,证明了光流运动估计技术提取高分率风场的可行性。 相似文献
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Codium, one of the largest marine green algal genera, is difficult to delimit species boundary accurately based on morphological identification only. DNA barcoding is a powerful tool for discriminating species of seaweeds. The plastid elongation factor TU(tuf A) is considered as maker to perform DNA barcoding of green algal species than rbc L gene due to universality and rapid evolution rate. We conducted DNA barcoding application to Codium specimens from the Jeju Island, Korea to overcome the limit of morphological identification and to confirm the species diversity. As a result of applying tuf A marker, we newly generated fifty-five tuf A barcodes to resolve eight species. Tuf A marker exhibited 6.1%–21.8% interspecific divergences, wider than the gap of rbc L exon 1,3.5%–11.5%. Molecular analysis of rbc L exon 1 sequences of Codium revealed eight distinct species like tuf A analysis separated in five phylogenetic groups. DNA barcoding of the genus Codium using tuf A marker is more helpful to overcome the limit of morphological identification, and this is more potential to reveal cryptic species and to resolve the relationships among subspecies than rbc L analysis alone. The complement of tuf A barcoding and rbc L analyses including morphology for the genus Codium in the northwestern Pacific will give much more reliable achievement for discovering species diversity and resolving the phylogenetic relationships. 相似文献
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报告分子外流源L1211 中新发现的12 个近红外HH 天体.在L1211 的~4’区域,取得了JHK’宽带和H2 v = 10 S(1) 发射线窄带的近红外图像.分析表明,新探测到的许多红外源与浓密分子云物理成协,其中有20 多个源表现出典型的T Tauri 星、Herbig Ae/Be星和原恒星的红外超.L1211 中的IRAS点源没有被观测到,可能是更深地埋于分子云中.对红外观测和分子线观测消光估计的比较显示,小于2μm 的近红外观测还不足以揭示深埋于分子云的整个年轻星团.根据近红外HH 天体的形态分布和红外源性质,能进一步证认这些HH 天体的激发源.其结果表明,L1211 分子云中具有多个红外源驱动的多个外流活动 相似文献
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