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101.
和声教学基本理论、技能要领及问题的探讨 总被引:1,自引:0,他引:1
通过对和声教学基本理论、技能要领及问题的探讨,揭示大小调功能体系及和声教学基本规律和存在的问题,提出观点和建议,为和声教学和实践的发展、突破,做点有意义的尝试。 相似文献
102.
Remote sensing of spatial patterns of urban renewal using linear spectral mixture analysis: A case of central urban area of Shanghai (1997―2000) 总被引:2,自引:0,他引:2
YUE Wenze XU Jianhua WU Jiawei XU Lihua 《科学通报(英文版)》2006,51(8):977-986
It is very important to integrate remote sensing with urban geography that the spectral mixture analysis technique is applied to urban land cover evolvement and its eco-environmental effect. Urban land cover is mainly composed of complicated artificial materials, which is the key factor to limit the development of the spectral mixture analysis technique. There are two main aspects in which the technique of spectral mixture analysis is applied to urban geography: one is to calculate vegetation fraction; the other is to build quantitative model of the urban impervious surface obtained from the combination between high albedo fraction and low albedo fraction. The technique of spectral mixture analysis is firstly applied to study urban renewal pattern, scale and mode which happened in Shanghai City from 1997 to 2000, 相似文献
103.
WU Weiren HUANG Biguang 《科学通报(英文版)》2006,51(21):2619-2623
A qualitative trait is usually controlled by a single gene, but it may be sometimes controlled by two or even more genes. This phenomenon is called gene interaction. Rapidly searching for linked mo- lecular markers via bulked segregant analysis (BSA) and then constructing regional linkage map with Mapmaker/Exp has become a common approach to mapping single major genes. However, methods and computer programs developed for mapping single major genes cannot be simply applied to interactive genes because the genetic patterns of gene interac- tions are quite different from that of single-gene in- heritance. Up to now, experimental methods for quickly screening molecular markers linked to inter- active genes and statistical methods and corre- sponding computer softwares for simultaneously analyzing the linkage relationships of multiple mo- lecular markers to an interactive gene have not been available. To solve this problem, in this paper, we propose a strategy for mapping interactive genes using BSA and Mapmaker/Exp. We demonstrate that all interactive genes can be mapped by the 'BSA Mapmaker/Exp' strategy using F2 generation (in a few cases, F3 generation is also needed). As BSA and Mapmaker/Exp have been broadly used in gene mapping studies and are well known by many re- searchers, the strategies proposed in this paper will be useful for practical researches. 相似文献
104.
武艳霞 《太原理工大学学报》2000,(4)
利用柔度法测定了不同龄期、不同配方下纤维增强砂浆试样的断裂韧度 KIC,得到了掺入纤维可使材料韧性增强的结论。 相似文献
105.
在前文的基础上,通过对重要的衣领结构参数的分析和纸样实验,全面深入地讨论了衣领结构参数间的相关关系;定量地描述了各结构参数对衣领结构的影响程度和变化规律;并对衣领结构3D-2D转换中的近似处理方法及经验数据进行了实验验证;为衣领结构应用模型的建立及其3D-2D转换方法的提供了科学的实验依据. 相似文献
106.
吴金明 《江南大学学报(自然科学版)》2000,(1)
本文主要从日本的历史,自然环境等方面,对日本语言发展、文学意识流、言语特征及使用心理状态方面的影响进行了探讨。 相似文献
107.
腐植酸中官能团的测定方法的研究 总被引:10,自引:0,他引:10
研究了腐植酸中总酸性基、羧基、羰基、醌基、甲氧基等基团的测定方法. 相似文献
108.
A mouse model for spinal muscular atrophy 总被引:1,自引:0,他引:1
The survival motor neuron gene is present in humans in a telomeric copy, SMN1, and several centromeric copies, SMN2. Homozygous mutation of SMN1 is associated with proximal spinal muscular atrophy (SMA), a severe motor neuron disease characterized by early childhood onset of progressive muscle weakness. To understand the functional role of SMN1 in SMA, we produced mouse lines deficient for mouse Smn and transgenic mouse lines that expressed human SMN2. Smn-/- mice died during the peri-implantation stage. In contrast, transgenic mice harbouring SMN2 in the Smn-/- background showed pathological changes in the spinal cord and skeletal muscles similar to those of SMA patients. The severity of the pathological changes in these mice correlated with the amount of SMN protein that contained the region encoded by exon 7. Our results demonstrate that SMN2 can partially compensate for lack of SMN1. The variable phenotypes of Smn-/-SMN2 mice reflect those seen in SMA patients, providing a mouse model for this disease. 相似文献
109.
110.
In this article the structure and properties of freeze-dried porous silk fibroin materials were tested and analyzed.The results indicated that for porous silk fibroin materials prepared by means of freeze-drying,if freez-ing temperature was below —20℃,the structure of silk fibroin was mainly amorphous with a little silk Ⅱ crystal structure,and if freezing temperature was above —20℃,quite a lot of silk Ⅰ crystal structure formed.Porous silk fibroin materials,with average pore diameter be- 相似文献