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对68个外显子-内含子-外显子序列片段以及相应的外显子-外显子序列片段的二级结构进行分析后发现,内含子5^端和3^端的碱基G(剪接位点)中大约90%位于二级结构的环区或是茎区的端部并靠近环,而且位于环区的G也多靠近环的基部;92%的外显子拼接位点也有类似性质。约82%的分枝点A位于环区或环与茎的连接部位。折叠结构的形成使剪接位点和分枝点在空间上彼此靠近。

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1996年11月至1997年6月, 于雅砻江下游干流及其支流鳡鱼河中采获一批白鱼属 Anabarilius 鱼类标本, 经鉴定为西昌白鱼1新亚种。 命名为西昌白鱼雅砻亚种 Anabariliusliuiyalongensissubsp. nov. 与其它3个亚种的主要鉴别特征是: 第1鳃弓外侧鳃耙为7~10, 其余3个亚种分别为: 西昌指名亚种 A. liuiliui 为12~14, 程海亚种 A. liuichenghaiensis 15~16, 宜良亚种 A. liuiyiliangensis 10~12. 种内亚种分化主要是受到同域生态隔离和地理隔离作用的影响。

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This 1991-1992 study was designed to expand previous research on body weight (BW) in Tibetan macaques (Macaca thibetana) at Mt. Emei. Data on BW were collected in late autumn (LA) and late winter (LW) in groups ranging above 1,200 m. Over the winter, the BW fell significantly from a mean of 16.8 to 11.4 kg in females and from 19.5 to 17.0 kg in males. The previously reported BW means of 12.8 kg for females and 18.3 kg for males, measured in late spring, are near the center of the annual BW range for this species. In addition, with the sharper decline of female BW (- 32% vs. - 13% seen in males), the sexual dimorphism ((M) over bar/(F) over bar) in BW increased from 1.16 in LA to 1.49 in LW. This finding may be related to differential parental investment by two sexes. (C) 1994 Wiley-Liss, Inc.

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After analyzing the secondary structures of 68 exon-intron-exon and the corresponding exon-exon sequence segments, it is found that about 90% of 5' and 3' terminal bases G (splicing sites) of introns are situated in the loops of secondary structures or at the ends of stems near the loops, and most of "G" s in loops are closed to the ends of loops. Approximately 92% of the connecting sites of the adjoining exons also show the similar features. About 82% of the branch point "A" s are situated in loops or at the ends of stems near the loops. Splicing sites and branch points approach each other in space because of the folding.

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We analyzed n-mers (n=3-8) in the local environment of 8,249,446 human SNPs and compared their distribution with that in the genome reference sequences. The results revealed that the short sequences, which contained at least one CpG dinucleotide, occurred

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Forecasting the returns of assets at high frequency is the key challenge for high-frequency algorithmic trading strategies. In this paper, we propose a jump-diffusion model for asset price movements that models price and its trend and allows a momentum strategy to be developed. Conditional on jump times, we derive closed-form transition densities for this model. We show how this allows us to extract a trend from high-frequency finance data by using a Rao-Blackwellized variable rate particle filter to filter incoming price data. Our results show that even in the presence of transaction costs our algorithm can achieve a Sharpe ratio above 1 when applied across a portfolio of 75 futures contracts at high frequency. © 2011 IEEE.