多型的

During the postgenomics era the information about genomic sequence and gene functions provides a new foundation for evolutionary biology and ecology As the first whole-genome sequenced plant Arabidopsis thaliana and its wild relatives have played a critical role in understanding the evolution of genomics and speciation Both A halleri and A lyrata are closely related to the model species A thaliana A halleri ssp gemmifera occurs in northeastern China Japan and Taiwan; while its sister A halleri ssp halleri is mainly distributed in Europe Geographical barriers such as Tienshan Mountain Range isolate these intraspecific sisters Likewise A lyrata ssp kamchatica and ssp lyrata occur in East Asia and North America respectively Such distribution patterns seem to be consistent with allopartic speciation The comparison between ancestral and extant polymorphism by multilocus can be informative about the population genetics of speciation In this study we collected and analyzed DNA sequences of 98 genes from four wild relatives of A thaliana A halleri ssp gemmifera A halleri ssp halleri A lyrata ssp kamchatica and A lyrata ssp lyrata The ancestral states of these four species were compared to each other in terms of level of genetic variation However the ancestral species at the time of speciation were substantially more polymorphic than the extant geographical populations The observations are not fully compatible with speciation by strict allopatry At some species pairs parapatric speciation seems more reasonable in speciation of Arabidopsis The 98 gene sequences are also used for the congruence test between gene genealogy and species phylogeny Only 28 genes support the species phylogeny but there are 23 genes supports another major genealogy { lyrata} thaliana Based on the phylogenetic position change of A lyrata ssp kamchatica and Ks value for each species pair suggested the recent directional gene flow between A halleri ssp gemmifera and A lyrata ssp kamchatica

阿拉伯芥是第一个完成基因体定序的开花植物，其基因体资讯提供植物学研究的重要依据；在解析阿拉伯芥属物种的亲缘关系以及种化机制等重要的演化议题时，阿拉伯芥近缘的野生物种自然成了不可或缺的关键；跟阿拉伯芥近缘的物种包括A halleri及A lyrata，其中A halleri ssp gemmifera主要分布於中国东北、日本以及台湾，与近缘的A halleri ssp halleri其分布於欧洲隔著天山及大陆的障蔽，而A lyrata ssp kamchatica主要分布於东北亚及台湾，与分布於北美五大湖的A lyrata ssp lyrata被北极圈所分隔，这样的分布模式暗示异域种化的可能。藉由多基因分析比较祖先物种与现生物种遗传歧异度的相关可提供讯息探讨种化时期的族群遗传结构，本研究针对A halleri ssp gemmifera、A halleri ssp halleri及A lyrata ssp kamchatica、A lyrata ssp lyrata四个物种，两对互为亚种的姊妹群，以阿拉伯芥为外群进行研究，在四个物种完成98个同源基因的分子序列，利用套装软体MCMCcoal来估算祖先物种的遗传变异，亦估算现生物种的核苷酸歧异度，观察到？多物种配对中祖先物种遗传多型性大於现生物种DNA歧异度，显示异域种化模型并无法完全解释阿拉伯芥属物种的种化模式，在某些物种配对间邻域种化模式应比异域种化更为可能；在基因树与物种树的比较，98个基因片段的亲缘模式只有28个是与已知物种树一致的，有23个基因其树状图支持{ lyrata} thaliana的型式，藉由kamchatica位置的变化以及估算各物种配对间的平均同义置换率，推测在A halleri ssp gemmifera与A lyrata ssp kamchatica间具有近代的单方向基因交流。

Carleman不等式及其在最优控制问题中的应用.Optimal control theory of distributed parameter systems mainly includes: Pontryagin's maximum principle; controllability; Hamilton-Jacobi equation (i.e., dynamic programming equation); time optimal control, etc.In this dissertation, we establish Pontryagin's maximum principle of optimal control problems governed by some nonlinear differential equations (parabolic differential equations, elliptic differential equations and 3-dimensional Navier-Stokes equations), which in particular could have local solut...

在这篇博士论文中，我们建立了非线性微分方程(包括抛物型微分方程，椭圆型微分方程以及3维Navier-Stokes方程)最优控制问题的庞特里雅金最大值原理，特别地，这些方程可能只有局部解或存在多解(我们称这样的系统为非适定系统，相应的最优控制问题为非适定最优控制问题)，以及适定的非线性发展方程最优控制问题的庞特里雅金最大值原理；我们研究了phase-field系统的时间最优控制问题以及Boussinesq系统的局部内可控性。

Blue jade Wan breaks the traditional package "hardly" the feeling, advocates the nature, comfortable, practical, individuality "soft" handbag, does not rigidly adhere to the tradition "the simple geometry", founds even more three-dimensional, the multi-structures, the multi-level three-dimensional concepts, set at variance the concept the modelling, in the material aspect unceasing attempt, the lining supplementary material aspect unceasing breakthrough tradition ideological mode, seeks for the new material in more scopes to express the design unceasingly.

蓝玉宛打破传统包的&硬&感，主张自然，舒适，实用，个性的&软&手袋，不拘泥于传统的&简单的几何型&，开创出更加立体，多结构，多层次的立体概念，解构概念的造型，在材料方面不断的尝试，面料辅料方面不断的突破传统思维模式，在更多范围中不断寻找新材料来表达设计。

The conclusion showed that the key point was temperature at 200～300 ℃ where the flame retardant was able to promote dewatering and charring of wood.

文中还分析了木材阻燃技术的发展方向，指出反应型木材阻燃剂是解决阻燃剂吸潮和流失问题的有效途径，纳米阻燃是亟待开发的高效阻燃技术，一剂多效的膨胀型阻燃剂是阻燃剂的发展方向之一。

He altered it and, in so doing, created first egg-shaped "orbits" and, finally, an ellipse with the sun placed at one focus.

在多次用他的模型预测火星位置失败之后，他换了一种模型，他先是新建了一种蛋型的&轨道&模型，最后才是椭圆型的模型，太阳位于椭圆的其中一个焦点上。

Because you all have done such a great job and found so many promising conformers, we feel that we can spend the enormous time and effort involved in a complete replication of the data on the old NAS in more worthwhile pursuits, like the deployment of new libraries.

因为大家完成了这么多的任务，而且发现了这么多有效的分子构型，我们感觉我们在复制旧 NAS 上的数据花费了太多的时间，应该关注一下更有意义的事情，比如说配置新分子库。

Udensis' genetic variation, its historical causes and dispersal, and references for the explanation of China's geological changes and post-Pleistocene geographical dispersal of plants.

由于七筋菇植物不同细胞型共存，两种细胞型的分布区相邻或重叠，为我们探讨七筋菇种群的遗传结构和遗传分化，多倍体的起源、扩散和演化，及其迁移路线提供了理想的天然研究场所。

The crystal structures of the two polymorphs are so similar that they can hardly be distinguished by usual polycrystalline X-ray diffraction methods.

后者是一种亚稳相。这两种多型体的结构非常相似，用通常的多晶衍射方法难以区分。

The UBC-868 is the most efficient primer which generates 16 polymorphic bands, including the most significant 900 bp polymorphic DNA fragment. The 900 bp fragment is specifically observed in vegetable soybean varieties which have black seed coat, except the yellow seed coat variety Kuo China.

其中以UBC868扩增出16个DNA条带为最多，且於电泳胶片上900 bp处有一明显的多型性条带，此DNA条带除了来自中国的Kuo China品系外，可视为常出现在黑色种皮毛豆中。

Scientists' attention is paid to the discription of the self-adjoint boundary condi-tions of singular differential operators during 50 years recently.

对称微分算子理论中自共轭域的描述，是微分算子理论中的基础问题之一，常型的问题在五十年代已得到解决，五十余年来人们更多的注意力放在奇型微分算子自共轭边界条件的描述上。

Plunder melds and run with this jewel!

掠夺melds和运行与此宝石！

My dream is to be a crazy growing tree and extend at the edge between the city and the forest.

此刻，也许正是在通往天国的路上，我体验着这白色的晕旋。