1000 resultados para related allies


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中国的苦苣苔科-长蒴苣苔族存在两个古老又难以界定的大属:唇柱苣苔属Chirita和长蒴苣苔属Didymocarpus。唇柱苣苔属至少有140种,其中75%以上的种分布在中国南部。尽管Wood和王文采(中国种)已经作出较为全面的修订,但唇柱苣苔属的界定以及属下再划分仍然存在争议。传统分类一直认为唇柱苣苔属非单系类群,尤其与长蒴苣苔属、小花苣苔属、文采苣苔属以及报春苣苔属等近缘属之间的关系难以确定,还需进一步研究。长蒴苣苔属已经被拆分为三个不同的属,其中的狭义长蒴苣苔在我国有20多种。针对以上问题,本文通过大量的标本研究、野外考察以及分子系统学研究,得出了一些初步的结果。 形态学 通过大量的标本观察及野外考察,发现唇柱苣苔属及其近缘类群营养性状变异非常复杂。然而,营养体变异受环境饰变大,不适合作为划分组和属等较高级分类单元的主要依据,是区分近缘种的主要分类依据。在生殖器官中,一些性状,如子房和蒴果形状和大小,在唇柱苣苔属和其近缘属中存在大量的过渡类型,不宜将单独或2-3个性状作为主要分类依据。同时笔者发现两个新种,即长萼唇柱苣苔(C. longicalyx J. M. Li & Y. Z. Wang)和匍匐唇柱苣苔(C. prostrata J. M. Li & Y. Z. Wang)。匍匐唇柱苣苔属于钩序唇柱苣苔组,系多年生植物,致使我们国家分布的钩序唇柱苣苔组扩大为两种。它的特殊习性以及极其有限的分布区表明,它是一个在不利的生境下偶尔幸存的残遗种。 2.分子系统学 首先通过对两个DNA片段ITS和trnL-F数据以及它们的联合数据进行最简约分析和贝叶斯分析,并结合形态特征演化来研究唇柱苣苔属唇柱苣苔组和小花苣苔属系统发育关系。结果表明,小花苣苔属和唇柱苣苔组(唇柱苣苔属)Chirita sect. Gibbosaccus构成一个单系群,强烈支持小花苣苔属归并到唇柱苣苔组(唇柱苣苔属)中,而且二者形态性状极其相似。上述事实说明唇柱苣苔组(唇柱苣苔属)和小花苣苔属具有很近的亲缘关系,而与麻叶唇柱苣苔组Chirita sect. Chirita关系较远。研究一些关键地区植物的物种形成,将提高对这些地区植物区系发生与发展的认识,喀斯特地区就是这样一个非常独特与关键的地区。特产于这种干湿交替、温度变化显著的特殊生境里的的类群,如唇柱苣苔组和小花苣苔属,存在着非常近的系统发育关系。最后笔者建议把小花苣苔属置于唇柱苣苔属唇柱苣苔组里,而不是将该属单立出来。 在上述研究基础上,本研究进一步选择唇柱苣苔属的其他近缘属,通过对两个DNA片段ITS和trnL-F数据以及联合数据进行最简约分析,旨在揭示在唇柱苣苔属内的系统发育及其和周边近缘属系统发育关系。该研究结果表明狭义长蒴苣苔属、朱红苣苔属、报春苣苔属、文采苣苔属以及小花苣苔属都置入唇柱苣苔属内。其中,报春苣苔属、文采苣苔属以及小花苣苔属和唇柱苣苔组具有相似的柱头,在系统树上,也构成一个单系分支。虽然许多学者认为柱头形状是很重要的分类性状,也是唯一用来界定唇柱苣苔属的,但是非常不可靠的,因而唇柱苣苔属至少分成两个属。 文采苣苔属和小花苣苔属无论从分子上还是从形态上都得不到证明是单系类群,应该归并到唇柱苣苔属中;而报春苣苔属很可能是最近从唇柱苣苔组里分化出来的类群。 东南长蒴苣苔和朱红苣苔属植物形态十分相似,除了营养体差别不大外,他们还具伸出花筒外的柱头和小而尖的花冠裂片等共同特征,分子树上也组成一个单系,为东南长蒴苣苔归并到朱红苣苔属提供了强有力的分子证据。 在狭义长蒴苣苔属Didymocarpus s. str.两个组中,Didymocarpus sect. Elati的一个种D. citrinus与长蒴苣苔组Didymocarpus sect. Didymocarpus构成姐妹群关系。二组植物构成一个单系分支又与圆唇苣苔属Gyrocheilos构成姐妹群关系。因此,虽然我们的数据支持圆唇苣苔属与长蒴苣苔属近缘,但是不支持圆唇苣苔属作为一个亚组放在长蒴苣苔里。

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Alliance formation is a critical dimension of social intelligence in political, social and biological systems. As some allies may provide greater ‘leverage’ than others during social conflict, the cognitive architecture that supports alliance formation in humans may be shaped by recent experience, for example in light of the outcomes of violent or non-violent forms intrasexual competition. Here we used experimental priming techniques to explore this issue. Consistent with our predictions, while men’s preference for dominant allies strengthened following losses (compared to victories) in violent intrasexual contests, women’s preferences for dominant allies weakened following losses (compared to victories) in violent intrasexual contests. Our findings suggest that while men may prefer dominant (i.e. masculine) allies following losses in violent confrontation in order to facilitate successful resource competition, women may ‘tend and befriend’ following this scenario and seek support from prosocial (i.e. feminine) allies and/or avoid the potential costs of dominant allies as long-term social partners. Moreover, they demonstrate facultative responses to signals related to dominance in allies, which may shape sex differences in sociality in light of recent experience and suggest that intrasexual selection has shaped social intelligence in humans.

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Little is known about the origin of basal-like breast cancers, an aggressive disease that is highly similar to BRCA1-mutant breast cancers. p63 family proteins that are structurally related to the p53 suppressor protein are known to function in stem cell regulation and stratified epithelia development in multiple tissues, and p63 expression may be a marker of basal-like breast cancers. Here we report that Delta Np63 isoforms of p63 are transcriptional targets for positive regulation by BRCA1. Our analyses of breast cancer tissue microarrays and BRCA1-modulated breast cancer cell lines do not support earlier reports that p63 is a marker of basal-like or BRCA1 mutant cancers. Nevertheless, we found that BRCA1 interacts with the specific p63 isoform Delta Np63 gamma along with transcription factor isoforms AP-2 alpha and AP-2 gamma. BRCA1 required Delta Np63 gamma and AP-2 gamma to localize to an intronic enhancer region within the p63 gene to upregulate transcription of the Delta Np63 isoforms. In mammary stem/progenitor cells, siRNA- mediated knockdown of Delta Np63 expression resulted in genomic instability, increased cell proliferation, loss of DNA damage checkpoint control, and impaired growth control. Together, our findings establish that transcriptional upregulation of Delta Np63 proteins is critical for BRCA1 suppressor function and that defects in BRCA1-Delta Np63 signaling are key events in the pathogenesis of basal-like breast cancer. Cancer Res; 71( 5); 1933-44. (c) 2011 AACR.

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Critical reading of science-based media reports is an authentic context in which to explore the mutual interests of teachers of science and English, who want to use science in the media to promote their subject discipline while encouraging cross-curricular learning. This empirical study focused on 90 teachers of science and English to explore their aptitude and capability for critical reading of science-based news reports. The influences of specialist subject culture and the extent of classroom experience contributed to the distinctive nature of the responses. The study revealed features in critical reading that were characteristic of the subject background of the participants. It suggested approaches to initial teacher education and ongoing professional development that would be mutually beneficial to teachers from different disciplines in promoting among pupils a critical approach to science-related news media.

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Integrating Enterprise Systems solutions in the curriculum of not only universities but all types of institutes of higher learning has been a major challenge for nearly ten years. Enterprise Systems education is surprisingly well documented in a number of papers on Information Systems education. However, most publications in this area report on the individual experiences of an institution or an academic. This paper focuses on the most popular Enterprise System - SAP - and summarizes the outcomes of a global survey on the status quo of SAP-related education. Based on feedback of 305 lecturers and more than 700 students, it reports on the main factors of Enterprise Systems education including, critical success factors, alternative hosting models, and students’ perceptions. The results show among others an overall increasing interest in advanced SAP solutions and international collaboration, and a high satisfaction with the concept of using Application Hosting Centers.