分子标记及其在甘薯种质资源和遗传育种中的应用

植物分子生物学和植物生物技术利用分子标记技术得到了大力发展,分子标记的创新、发展与应用对其起了积极的推动作用,本文就RFLP、AFLP、RAPD、DAF、SSR、CAPS分子标记的原理与技术及其在甘薯种质资源和遗传育种中的应用作一介绍     

Genetic linkage map ofBrassica campestris L. using AFLP and RAPD markers

A genetic linkage map comprised of 131 loci was constructed with an F₂ population derived from an inter-subspecific cross betweenBrassica campestris L. ssp.chinensis cv. ‘aijiaohuang’ and ssp.rapifera cv. ‘qisihai’. The genetic map included 93 RAPD loci, 36 AFLP loci and 2 morphological loci organized into 10 main linkage groups (LGs) and 2 small groups, covering 1810.9cM with average distance between adjacent markers being approximately 13.8cM. The map is suitable for identification of molecular markers linked to important agronomic traits, QTL analysis, and even for marker-assisted selection in breeding programs of Chinese cabbage and turnip. Project (No. 39870509) supported by the National Natural Science Foundation of China     

序列无约束极小化技术和遗传算法在非线性规划中的应用

本文提出了一种求解带约束非线性规划问题的一般方法。与现有的方法相比 ,它不受可导性 ,单峰性和是否病态等因素的限制 ,适用范围广。实例说明该算法对带约束非线规划问题的求解十分有效     

Nonlinear modelling of a SOFC stack by improved neural networks identification

The solid oxide fuel cell (SOFC) is a nonlinear system that is hard to model by conventional methods. So far,most existing models are based on conversion laws,which are too complicated to be applied to design a control system. To facilitate a valid control strategy design,this paper tries to avoid the internal complexities and presents a modelling study of SOFC per-formance by using a radial basis function (RBF) neural network based on a genetic algorithm (GA). During the process of mod-elling,the GA aims to optimize the parameters of RBF neural networks and the optimum values are regarded as the initial values of the RBF neural network parameters. The validity and accuracy of modelling are tested by simulations,whose results reveal that it is feasible to establish the model of SOFC stack by using RBF neural networks identification based on the GA. Furthermore,it is possible to design an online controller of a SOFC stack based on this GA-RBF neural network identification model.     

浅谈《九章算术》对古今数学的影响

《丸章算术》是中国古代数学的核心,形成了我国古代初等数学体系,不仅对我国古代数学的发展有着深远的影响,而且也对现代数学教育有很大的推动作用,但它的知识体系的特点也对现代数学发展产生一定的制约作用和负面影响。     

Diversity arrays technology (DArT) for studying the genetic polymorphism of flue-cured tobacco (Nicotiana tabacum)

Diversity arrays technology (DArT) is a microarray-based marker system that achieves high throughput by reducing the complexity of the genome. A DArT chip has recently been developed for tobacco. In this study, we genotyped 267 flue-cured cultivars/landraces, including 121 Chinese accessions over five decades from widespread geographic regions in China, 103 from the Americas, and 43 other foreign cultivars, using the newly developed chip. Three hundred and thirty polymorphic DArT makers were selected and used for a phylogenetic analysis, which suggested that the 267 accessions could be classified into two subgroups, which could each be further divided into 2–4 sections. Eight elite cultivars, which account for 83% of the area of Chinese tobacco production, were all found in one subgroup. Two high-quality cultivars, HHDJY and Cuibi1, were grouped together in one section, while six other high-yield cultivars were grouped into another section. The 330 DArT marker clones were sequenced and close to 95% of them are within non-repetitive regions. Finally, the implications of this study for Chinese flue-cured tobacco breeding and production programs were discussed.     

小学数学应用题认知诊断测验编制及效度验证

本研究旨在基于事先构建的理论模型,编制小学数学应用题认知诊断测验,并通过认知诊断评估对其效度进行验证。采用质性研究和量化研究两条思路,通过认知分析、大声思维和测验等方法,探索了认知诊断评估从理论模型构建到测验编制及其效度验证的过程。在理论模型构建和测验编制方面,所得结果表明认知分析和大声思维相结合能够合理地构建实质心理学的认知模型,并且基于该认知模型自上而下的测验设计是与认知诊断评估流程相吻合的。通过认知诊断评估所获取的数据分析表明,该测验的结构效度、内部效度和外部效度均达到理想水平,基于事先构建的认知模型所编制的认知诊断测验能够作为认知诊断评估的有效工具,有助于发掘和诊断学生数学应用题解决中的认知错误。     

GLABROUS INFLORESCENCE STEMS regulates trichome branching by genetically interacting with SIM in Arabidopsis

Arabidopsis trichomes are large branched single cells that protrude from the epidermis. The first morphological indication of trichome development is an increase in nuclear content resulting from an initial cycle of endoreduplication. Our previous study has shown that the C2H2 zinc finger protein GLABROUS INFLORESCENCE STEMS (GIS) is required for trichome initiation in the inflorescence organ and for trichome branching in response to gibberellic acid signaling, although GIS gene does not play a direct role in regulating trichome cell division. Here, we describe a novel role of GIS, controlling trichome cell division indirectly by interacting genetically with a key endoreduplication regulator SIAMESE (SIM). Our molecular and genetic studies have shown that GIS might indireclty control cell division and trichome branching by acting downstream of SIM. A loss of function mutation of SIM signficantly reduced the expression of GIS. Futhermore, the overexpression of GIS rescued the trichome cluster cell phenotypes of sim mutant. The gain or loss of function of GIS had no significant effect on the expression of SIM. These results suggest that GIS may play an indirect role in regulating trichome cell division by genetically interacting with SIM.     

Allelic frequency distributions of 21 non-combined DNA index system STR loci in a Russian ethnic minority group from Inner Mongolia, China

We studied the allelic frequency distributions and statistical forensic parameters of 21 new short tandem repeat (STR) loci and the amelogenin locus, which are not included in the combined DNA index system (CODIS), in a Russian ethnic minority group from the Inner Mongolia Autonomous Region, China. A total of 114 bloodstain samples from unrelated individuals were extracted and co-amplified with four fluorescence-labeled primers in a multiplex polymerase chain reaction (PCR) system. Using capillary electrophoresis, the PCR products of the 21 STR loci were separated and genotyped. A total of 161 alleles were observed in the Russian ethnic minority group, and corresponding allelic frequencies ranged from 0.0044 to 0.5965. The 21 non-CODIS STR loci of the Russian ethnic minority group were characterized by high genetic diversity and therefore may be useful for elucidating the population’s genetic background, for individual identification, and for paternity testing in forensic practice.     

一种基于遗传算法的作曲方法

本文介绍了一种基于遗传算法,以乐段为单位的作曲方法。该方法能生成具有相对完整乐思的音乐片段,并引入了音乐的风格化特征,能按照用户的情感因素产生用户所需的音乐片断。