查询词典 critical

To combat severe alkylation conditions in this critical area.

在关键应用场合抵抗严酷的烃化环境。

Secondly, based on the phase behaviors, a new method for partition of supercritical reaction regions is used to study benzene-propylene alkylation under near critical conditions.

在相行为研究的基础上，使用对近临界点区域分区的方法进行丙烯与苯烷基化反应的研究。

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。

In present review, focusing on the low-copy nuclear genes, we summarize the appli-cation of these genes in the phylogenetic reconstruction of allopolyploid plants and bring forward some critical issues in this field.

以低拷贝核基因为主线，概述了其在多倍体植物系统发生中的应用和相关注意事项，并对其在多倍体植物中的表达变化及其分子机制进行了探讨，系统地介绍了国际上相关领域的研究成果和最新动向。

"We won't be using wireless for critical control applications at our plant anytime soon," said Jim Albert, a process engineer at Allston, Mass-based Genzyme Corp."We're just not comfortable with that."

"我们不会马上在工厂的关键控制应用上使用无线技术"吉姆艾伯特，一个来自奥斯顿，Mass-based Genzyme公司的工艺工程师，"我们只是觉得不放心。"

Relationship between null and alternative hypothesis; Level of significance; typical steps of hypothesis test, two type errors, critical values.

教学目的：通过学习领会统计假设测验即统计推断的原理及其基本步骤，统计假设测验的两类错误及其关系。

Molecular sieve 3A is a kind of alkali aluminosilicate, able to adsorb molecules with their critical diameters no more than 3A.

分子筛3A现一种碱铝硅酸盐，能够吸附分子与他们的临界直径不超过3 A条。

Instead, I propose that we even more ambitiously recast ourselves as a strategic partner to the business—not because we want to be seen as a critical path, but because we generally want to have a stake in the success of the business.

相反，我建议我们更 ambitiously 改造自己为战略业务伙伴，不是因为我们想要被视为一个关键的路径，而由于通常需要有一个 stake 业务的成功。

The whole is divided into two parts. The first part is the design of explosive vessel which is mainly used to test the critical explosion temperature of aqueous solution of ammonium nitrate.

设计的具体内容分为两大部分，第一部分是用来测试硝酸铵水溶液爆炸温度的爆炸容器设计，第二部分是测试装置设计。

Results The concentration of IL-18 in tubercular pleural effusion group was (1200.34±530.25) pg/ml, while that of the malignant pleural effusion group was (240.40±80.49) pg/ml, the former was significantly higher than the latter (P.01); The analytic result of ROC curve showed that 360 pg/ml IL-18 could be seen as the critical value for diagnosis of the tubercular pleural effusion, whose sensitivity and specificity respectively was 89.2% and 93.5%.

结果 结核性胸腔积液组IL-18的浓度为(1200.34±530.25)pg/ml，恶性胸腔积液组IL-18的浓度为(240.40±80.49)pg/ml，结核性胸腔积液组IL-18的浓度显著高于恶性胸腔积液组(P.01)；ROC曲线分析结果显示IL-18以360pg/ml为诊断结核性胸腔积液的临界值，其敏感度和特异度分别是89.2%和93.5%。

The split between the two groups can hardly be papered over.

这两个团体间的分歧难以掩饰。

This approach not only encourages a greater number of responses, but minimizes the likelihood of stale groupthink.

这种做法不仅鼓励了更多的反应，而且减少跟风的可能性。