998 resultados para polyphyletic origin


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Compared to grain sorghums, sweet sorghums typically have lower grain yield and thick, tall stalks which accumulate high levels of sugar (sucrose, fructose and glucose). Unlike commercial grain sorghum (S. bicolor ssp. bicolor) cultivars, which are usually F1 hybrids, commercial sweet sorghums were selected as wild accessions or have undergone limited plant breeding. Although all sweet sorghums are classified within S. bicolor ssp. bicolor, their genetic relationship with grain sorghums is yet to be investigated. Ninety-five genotypes, including 31 sweet sorghums and 64 grain sorghums, representing all five races within the subspecies bicolor, were screened with 277 polymorphic amplified fragment length polymorphism (AFLP) markers. Cluster analysis separated older sweet sorghum accessions (collected in mid 1800s) from those developed and released during the early to mid 1900s. These groups were emphasised in a principle component analysis of the results such that sweet sorghum lines were largely distinguished from the others, particularly by a group of markers located on sorghum chromosomes SBI-08 and SBI-10. Other studies have shown that QTL and ESTs for sugar-related traits, as well as for height and anthesis, map to SBI-10. Although the clusters obtained did not group clearly on the basis of racial classification, the sweet sorghum lines often cluster with grain sorghums of similar racial origin thus suggesting that sweet sorghum is of polyphyletic origin within S. bicolor ssp. bicolor.

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牡丹在中国被称作“花中之王”。我国不仅是全部野生牡丹的原产地,也是栽培牡丹最早的驯化地。野生牡丹共有8个种,分布于云南、四川、湖北、甘肃、陕西、山西、安徽、河南和西藏等9省区,因其具有很大的观赏和药用价值,而在中国和世界温带地区广泛栽培。本研究利用形态特征和4个核基因片段(三个Adh 基因和GPAT基因片断)的核苷酸序列变异对牡丹组的种间系统发育关系进行了分析,并对我国栽培牡丹四个品种群的101个代表品种的可能祖先进行了形态学鉴定和分子诊断标记研究。在此基础上,利用核编码叶绿体表达的GPAT基因的(大内含子)部分序列和叶绿体基因组的trnS – trnG 和 rpS16 – trnQ两个基因间隔区的DNA序列变异重建了栽培牡丹37个代表品种和26个野生居群间的谱系关系。结果表明:(1)GPAT基因树是迄今得到的分辨率最好,并具有很高自展值支持的牡丹组种间系统发育关系树;(2)GPAT基因树和形态学证据一致支持银屏牡丹(P. suffruticosa ssp. yinpingmudan), 凤丹(P. ostii), 紫斑牡丹(P. rockii), 卵叶牡丹(P. qiui), 和矮牡丹 (P. jishanensis) 参与了栽培牡丹的起源;(3)叶绿体DNA单倍型网络树(network)进一步证实上述5个祖先类群的4个(矮牡丹除外)可能参与了栽培牡丹的母系起源。37个品种的GPAT基因谱系和叶绿体DNA单倍型网络树一致表明银屏牡丹是栽培牡丹最主要的祖先,其次是紫斑牡丹、凤丹、和卵叶牡丹;(4)我们的分子证据不支持形态学证据关于矮牡丹是栽培牡丹最主要的野生祖先的推测;(5)形态学和分子诊断标记证据表明,101个品种中有65.35 % 的品种具有两个以上野生种的特征,18.81 % 品种同时具有 Eco R I (+) 和 InDel51(+)物种特异分子标记。对37个品种的GPAT基因谱系和叶绿体DNA谱系比较发现,其中35个可能是杂种起源。另外,对7个古代牡丹品种(据文献记载)的GPAT基因的不同克隆类型进行测序和谱系分析,结果表明其中4 个为杂种起源。上述证据充分表明杂交和(或)渗入杂交在牡栽培牡丹的起源和进化中发挥了重要作用。根据本研究的结果,结合现有的形态学数据、考古记录,以及有关牡丹栽培和驯化历史的记载,我们对栽培牡丹的起源和驯化历史总结如下。牡丹的栽培迄今有1,600 – 2,000年,栽培牡丹最迟起源于1,500年前。最初通过驯化和对突变的选择获得原始品种。由于牡丹品种可以通过无性和(或)有性方式进行繁殖,其后新的品种通过如下方式产生:(1)对突变的选择,(2)对栽培类型和野生种之间或栽培类型之间杂交和(或)渗入杂交产生的实生苗的选择。由于绝大部分(如果不是全部)早期的原始品种已绝灭,现有栽培牡丹是起源于各种人工和自然进化力共同作用的结果,其中包括多次驯化、人工选择、突变、杂交和渗入杂交等。据作者所知,栽培牡丹的这种 ‘compilospecies’ 起源和驯化模式是目前已研究过的主要栽培作物中未见报道的。 因此,本研究不仅为栽培牡丹的多系起源和驯化历史提供了可信的分子证据,同时也为利用单拷贝基因的内含子序列构建栽培作物及其近缘野生祖先间的种系发生关系提供了成功的例子。另外,本研究也为同时利用核和叶绿体基因组的非编码DNA序列研究杂交在栽培作物的起源和进化的中作用提供了成功的例子。

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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The length polymorphism of ribosomal DNA ITS-1 intergenic spacer was analyzed in eight species of triatomines belonging to Triatoma, Rhodnius, and Panstrongylus genera. The analyzed species were Rhodnius domesticus, R. neivai, R. robustus, Triatoma brasiliensis, T. infestans, T. vitticeps, Panstrongylus megistus, and P. herreri. These insects are vectors of Chagas' disease, one of the most prominent public health problems among South American countries. This work allowed the differentiation between species of the Triatomini and Rhodniini tribes through the analysis of ITS-1 length polymorphism by PCR and RFLP techniques. The species of the Triatoma and Panstrongylus genera presented an amplified ITS-1 fragment between 600 and 1000 bp, whereas Rhodnius presented a less variable ITS-1 length fragment, around 300 bp, which could reflect the monophyletic origin of the Rhodniini tribe. Species belonging to this genus were further differentiated by RFLP with HaeIII and AluI endonucleases. Our results corroborate the hypothesis of polyphyletic origin in this group of insects and contribute to knowledge about evolutionary relationships in triatomines.

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A new Expiratory Droplet Investigation System (EDIS) was used to conduct the most comprehensive program of study to date, of the dilution corrected droplet size distributions produced during different respiratory activities.----- Distinct physiological processes were responsible for specific size distribution modes. The majority of particles for all activities were produced in one or more modes, with diameters below 0.8 µm. That mode occurred during all respiratory activities, including normal breathing. A second mode at 1.8 µm was produced during all activities, but at lower concentrations.----- Speech produced particles in modes near 3.5 µm and 5 µm. The modes became most pronounced during continuous vocalization, suggesting that the aerosolization of secretions lubricating the vocal chords is a major source of droplets in terms of number.----- Non-eqilibrium droplet evaporation was not detectable for particles between 0.5 and 20 μm implying that evaporation to the equilibrium droplet size occurred within 0.8 s.

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The aim of this paper is to explore a new approach to obtain better traffic demand (Origin-Destination, OD matrices) for dense urban networks. From reviewing existing methods, from static to dynamic OD matrix evaluation, possible deficiencies in the approach could be identified: traffic assignment details for complex urban network and lacks in dynamic approach. To improve the global process of traffic demand estimation, this paper is focussing on a new methodology to determine dynamic OD matrices for urban areas characterized by complex route choice situation and high level of traffic controls. An iterative bi-level approach will be used, the Lower level (traffic assignment) problem will determine, dynamically, the utilisation of the network by vehicles using heuristic data from mesoscopic traffic simulator and the Upper level (matrix adjustment) problem will proceed to an OD estimation using optimization Kalman filtering technique. In this way, a full dynamic and continuous estimation of the final OD matrix could be obtained. First results of the proposed approach and remarks are presented.

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Bovine intestine was dried in a heat pump fluid bed combination. Minimum fluidisation velocity was calculated by Ergun Equation and some relations were established.

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This article offers managerial implications for improving consumer perceptions of a product’s country of origin.

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For ESL teachers working with low-literate adolescents the challenge is to provide instruction in basic literacy capabilities while also realising the benefits of interactive and dialogic pedagogies advocated for the students. In this article we look at literacy pedagogy for refugees of African origin in Australian classrooms. We report on an interview study conducted in an intensive English language school for new arrival adolescents and in three regular secondary schools. Brian Street’s ideological model is used. From this perspective, literacy entails not only technical skills, but also social and cultural ways of making meaning that are embedded within relations of power. The findings showed that teachers were strengthening control of instruction to enable mastery of technical capabilities in basic literacy and genre analysis. We suggest that this approach should be supplemented by a critical approach transforming relations of linguistic power that exclude, marginalise and humiliate the study students in the classroom.

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A favorable product country of origin (e.g., an automobile made in Germany) is often considered an asset by marketers. Yet a challenge in today's competitive environment is how marketers of products from less favorably regarded countries can counter negative country of origin perceptions. Three studies investigate how mental imagery can be used to reduce the effects of negative country of origin stereotypes. Study 1 reveals that participants exposed to country of origin information exhibit automatic stereotype activation. Study 2 shows that self-focused counterstereotypical mental imagery (relative to other-focused mental imagery) significantly inhibits the automatic activation of negative country of origin stereotypes. Study 3 shows that this lessening of automatic negative associations persists when measured one day later. The results offer important implications for marketing theory and practice.

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Historically, determining the country of origin of a published work presented few challenges, because works were generally published physically – whether in print or otherwise – in a distinct location or few locations. However, publishing opportunities presented by new technologies mean that we now live in a world of simultaneous publication – works that are first published online are published simultaneously to every country in world in which there is Internet connectivity. While this is certainly advantageous for the dissemination and impact of information and creative works, it creates potential complications under the Berne Convention for the Protection of Literary and Artistic Works (“Berne Convention”), an international intellectual property agreement to which most countries in the world now subscribe. Under the Berne Convention’s national treatment provisions, rights accorded to foreign copyright works may not be subject to any formality, such as registration requirements (although member countries are free to impose formalities in relation to domestic copyright works). In Kernel Records Oy v. Timothy Mosley p/k/a Timbaland, et al. however, the Florida Southern District Court of the United States ruled that first publication of a work on the Internet via an Australian website constituted “simultaneous publication all over the world,” and therefore rendered the work a “United States work” under the definition in section 101 of the U.S. Copyright Act, subjecting the work to registration formality under section 411. This ruling is in sharp contrast with an earlier decision delivered by the Delaware District Court in Håkan Moberg v. 33T LLC, et al. which arrived at an opposite conclusion. The conflicting rulings of the U.S. courts reveal the problems posed by new forms of publishing online and demonstrate a compelling need for further harmonization between the Berne Convention, domestic laws and the practical realities of digital publishing. In this article, we argue that even if a work first published online can be considered to be simultaneously published all over the world it does not follow that any country can assert itself as the “country of origin” of the work for the purpose of imposing domestic copyright formalities. More specifically, we argue that the meaning of “United States work” under the U.S. Copyright Act should be interpreted in line with the presumption against extraterritorial application of domestic law to limit its application to only those works with a real and substantial connection to the United States. There are gaps in the Berne Convention’s articulation of “country of origin” which provide scope for judicial interpretation, at a national level, of the most pragmatic way forward in reconciling the goals of the Berne Convention with the practical requirements of domestic law. We believe that the uncertainties arising under the Berne Convention created by new forms of online publishing can be resolved at a national level by the sensible application of principles of statutory interpretation by the courts. While at the international level we may need a clearer consensus on what amounts to “simultaneous publication” in the digital age, state practice may mean that we do not yet need to explore textual changes to the Berne Convention.