无法研究的

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。

The researchers point out that there are many things they cannot be sure about .

研究人员指出，有很多事情是他们无法确定的。

The researchers are not sure of the mechanism that causes the nitrate in the beetroot juice to boost stamina.

研究人员无法确定的机制，导致硝酸盐甜菜汁提高耐力。

Compton observes that there are still many unanswered questions about OIH, and research investigations are ongoing.

康普顿指出，仍然有许多无法回答的问题，有关马尿酸钠，研究调查正在进行之中。

Themselves, for those who may be subject to giving consent under duress, for

对於无法自行同意或拒绝研究的人、对於可能在胁迫下行使同意

Like reforming outside the system in our country,we research the economic development in the minority region outside the system,that is winding out the minority factor.after the latent capacity of extensive increasing gives play to,the minority factor becomes impassable furtherly in the economic development of minority region,because it can not solute the problem that how to mix the minority factor with the problem of the economic development in minority region,the academic circle sinks into the passive condition of application and countermeasure study,adapt to this learning dilemma,the minority region is at a late-developing stage,ignoring the minority factor imitating simply the development and industrial model of the developed region is a fairly universal selection of economic development, Adapt to the selection.,On the development policy in the minority region,A high premium comes to be placed on the tilting of the policy and helping of the economic things.

与我国体制外改革相类似，长期以来我们对民族地区的经济发展也是"体制外"及绕开民族因素进行的，这种发展模式在粗放增长的潜力得到发挥之后，民族因素成为民族地区经济进一步发展不可逾越的因素，由于无法解决如何融合民族因素和民族地区经济发展的问题，学术界陷入应用研究和对策研究的被动局面。

Fenestra greatly enhances the value of in vivo imaging by not only improving the quality of the images, but more importantly, enabling researchers to perform studies designed to answer questions they didn't even know they could ask before this technology was available, remarked Michael Beeuwsaert, president and CEO of Alerion Biomedical, Inc.

Fenestra极大地提高了体内成像的价值，不仅提高了成像质量，而且更重要的是，允许研究人员开展各种研究，用以解答在这项技术投入使用之前无法解决的问题。

The current study was not able to replicate the findings from the previous study.

目前的研究是无法复制的结果从先前的研究。

This region has been put fourth regional groundwater resource evaluation from year 1956 to 2002. These evaluation all take Quaternary groundwater resources as exploited study objectives, evaluate plains and montanic groundwater separately, didn"t consider overall portray groundwater hydrological system relation between input and output, couldn"t simulate groundwater hydrological process with circumstance fluctuation. Therefore, it"s necessary to reevaluate Sanjiang Plain"s groundwater resources on the basis of predecessors study.

该区自1956年至2002年主要进行了四次区域性的地下水资源评价工作，这些评价均以第四系地下水资源为研究对象，以开发为目的对平原区和山丘区地下水资源分别评价，没有考虑全面刻画地下水文系统输入输出的转化关系，无法模拟变化环境下的地下水文过程，因此，有必要在前人研究的基础上，重新评价三江平原地下水资源。

With the development time extension, the development effect worse gradually of Chaoyanggou oilfield, There is some low permeability thin oil that traditional production techniques can not realized in Fuyu and Yang da cheng zi layer of Chaoyanggou oilfield. The crude oil viscosity is high; the relationship between viscosity and temperature is sensitive. The viscosity has big fluctuating along with the temperature change. According to the development experience of inspissated pool and the research results of numerical simulation by STARS, thermal recovery technique is an efficient method used to improve the development effectiveness of low permeable and high viscosity blocks.

随着开发时间的延长，朝阳沟油田开发效果逐渐变差，扶余、扬大城子油层存在常规开采工艺技术无法满足的低渗透稀油，根据稠油油田开发经验和应用商业化软件 STARS 热采模型蒸汽吞吐数值模拟研究结果，采用热力采油技术是改善低渗透、高粘度区块开发效果的有效途径，因此在朝阳沟油田开展热力采油现场应用研究。

I didn't watch TV last night, because it .

昨晚我没有看电视，因为电视机坏了。

Since this year, in a lot of villages of Beijing, TV of elevator liquid crystal was removed.

今年以来，在北京的很多小区里，电梯液晶电视被撤了下来。