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31.
江滨 《四川畜牧兽医学院学报》2007,5(4):192-194
经济发展、社会进步、科技发达要依赖劳动者素质的提高,劳动者素质的提高要依赖素质教育,素质教育是全面提高公民思想道德、文化素养、身心素质等方面发展水平的教育。文中论述了素质教育的含义、结构、特征与实施方法。同时比较分析了素质教育与应试教育的区别,进一步明确了素质教育的特点和宗旨。 相似文献
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讨论了一类Riesz平均与BMO函数生成的交换子的L^p有界性问题。得到的结果表明在超曲面的高斯曲率不为零的条件下,与经典的Bochmer-Riesz平均有相类似的结果。 相似文献
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生态规划技术方法研究进展 总被引:1,自引:0,他引:1
概述了国内外生态规划技术方法的研究进展,分析了生态规划中存在的问题,并对生态规划的发展趋势进行了展望。 相似文献
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仿生学在科学创新中具有重要作用,国内外学者对此进行了大量研究。在回顾分析仿生学重大事件的基础上,提出了仿生学经历了4个发展时期:萌芽时期、建立时期、巩固时期与现代时期,指出了仿生学的重大贡献是源头创新的研究理念与方法,并能在未来的所有领域内应用、取得突破性研究成果。 相似文献
37.
Summary Inheritance of raw cucumber fruit texture (Magness-Taylor Fruit Pressure Tester firmness) was investigated over a 4-year period from 1971–1974. Results from 2 separate but related experiments suggested that firmness was quantitatively inherited with sufficient additive effects to permit gain from selection. In a selection study within 4 F2 populations derived from crosses between firm (Chipper and Gy3) and soft (Mincu and Green F) fruit type cultivars, variation among and within F3 and F4 families was significant but overall family means were not significantly higher than the high parent in any of the 4 crosses. Narrow sense heritability estimates for fruit texture were 0.80 in the Mincu × Chipper population and 0.77 in the Green F × Chipper, Mincu × Gy3, and Gy3 × Green F crosses. In a separate experiment, generation means analysis was used to assess the mode of gene action in 2 crosses: Green F × Chipper, and Gy3 × Green F. Additive genetic effects accounted for 98.8% and 99.3% of the total genetic variation within each cross, respectively.Scientific Journal Series Paper No. 9794. 相似文献
38.
Adaptation of quinoa (Chenopodium quinoa) to Northern European agriculture: studies on developmental pattern 总被引:1,自引:0,他引:1
Sven-Erik Jacobsen 《Euphytica》1997,93(1):41-48
The inheritance of resistance to clubroot, caused by Plasmodiophora brassicae in Brassica oleracea was studied in the F1, F2and backcross progenies of three crosses between resistant and susceptible doubled haploid lines. Fresh weights of affected (CW) and healthy (HRW) parts of the root system were measured and R = ln((HRW+0.5)/(CW+0.5)) was used as a measure of resistance. R was shown to have a normally distributed error term with a constant standard deviation over the entire scale. Analysis of means indicated the presence of two complementary resistance genes in one of the crosses. In the other two crosses analysis of means also indicated two-locus interactions, in these cases reducing the cumulative effects of loci homozygous for resistance or for susceptibility alleles. The numbers of segregating resistance genes in these two crosses could not be determined. The presence of epistatic interactions precluded analysis of variance; therefore in this case the measurements were not more informative than the symptom grades analyzed in a previous study.R showed a high rank correlation (-0.85) with symptom grades assigned to the same plants. The results of genetic analyses of R were generally in agreement with those obtained earlier using symptom grades. Symptom grades can therefore be regarded as a reliable measure of symptom development, despite their more subjective nature. 相似文献
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浅析科右中旗速生丰产林基地建设条件和技术措施 总被引:1,自引:0,他引:1
田秀艳 《内蒙古林业调查设计》2011,34(2):22-23,54
文章通过速生丰产林基地建设条件分析,进行了工程区划分,提出速生丰产林建设模式和技术措施。 相似文献