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131.
本文从距离矩阵和邻接矩阵出发,结合矩阵的数学知识,提出了一种新的拓扑指数Qx=(W×V)1/8,用最小二乘法拟合b.p.(℃),得到线性回归方程为:b.p.(℃)=-277.814+165.248Qx(r=0.993)  相似文献   
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论文尝试用西方现代翻译理论,解读张爱玲改写和翻译《金锁记》的第4个译本The Golden Cangue,以期考察她如何在客观求真的文本表象下,由翻译传达词语的信息与意义上升到翻译是诗意的探索,并在实践上参与了西方现代翻译理论的建构。  相似文献   
134.
MBA education has become the fastest growing segment of education in China in recent years and a segment that can now be considered indispensible. However, how best to teach it has long been a source of debate. One of the key issues is how to match student traits with teaching methods. While engaged as teachers of marketing management, the authors collected data by questionnaire, carried out empirical research and data comparison, and undertook contingency analysis. It was found that different personal traits in students lead to different attitudes towards teaching methods. A student’s major in college, gender, and sector of employment has little influence on attitudes towards teaching methods, while age, the most sensitive factor, plays the biggest role, followed by job and class. Therefore, these factors should be taken into consideration when arranging classes, developing the curriculum, and planning teaching methods.  相似文献   
135.
文章指出高校应积极探索校务公开的工作思路和适用条件保障,使之有机融入学校管理工作中,注重依法办校、民主办学、民主管理、民主监督,改善校内行政权力,克服原来制度上的弊病,促进大学学术繁荣.  相似文献   
136.
刲股疗亲作为一种孝行,在清代的休宁地区有刲股者队伍庞大,成分复杂;刲股施药对象扩大;刲股方式渐趋理性,刲股行为隐蔽及疗效不确定等特点,而促成此态势的原因亦相当复杂。  相似文献   
137.
Soybean accounts for more than half of the global production of oilseed and more than a quarter of the protein used globally for human food and animal feed. Soybean domestication involved parallel increases in seed size and oil content, and a concomitant decrease in protein content. However, science has not yet discovered whether these effects were due to selective pressure on a single gene or multiple genes. Here, re-sequencing data from >800 genotypes revealed a strong selection during soybean domestication on GmSWEET10a. The selection of GmSWEET10a conferred simultaneous increases in soybean-seed size and oil content as well as a reduction in the protein content. The result was validated using both near-isogenic lines carrying substitution of haplotype chromosomal segments and transgenic soybeans. Moreover, GmSWEET10b was found to be functionally redundant with its homologue GmSWEET10a and to be undergoing selection in current breeding, leading the the elite allele GmSWEET10b, a potential target for present-day soybean breeding. Both GmSWEET10a and GmSWEET10b were shown to transport sucrose and hexose, contributing to sugar allocation from seed coat to embryo, which consequently determines oil and protein contents and seed size in soybean. We conclude that past selection of optimal GmSWEET10a alleles drove the initial domestication of multiple soybean-seed traits and that targeted selection of the elite allele GmSWEET10b may further improve the yield and seed quality of modern soybean cultivars.  相似文献   
138.
According to the statistics of the World Health Organization, an estimated 17.9 million people die from cardiovascular diseases each year, representing 31% of all global deaths. Continuous non-invasive arterial pressure (CNAP) is essential for the management of cardiovascular diseases. However, it is difficult to achieve long-term CNAP monitoring with the daily use of current devices due to irritation of the skin as well as the lack of motion artifacts suppression. Here, we report a high-performance skin-like optoelectronic system integrated with ultra-thin flexible circuits to monitor CNAP. We introduce a theoretical model via the virtual work principle for predicting the precise blood pressure and suppressing motion artifacts, and propose optical difference in the frequency domain for stable optical measurements in terms of skin-like devices. We compare the results with the blood pressure acquired by invasive (intra-arterial) blood pressure monitoring for >1500 min in total on 44 subjects in an intensive care unit. The maximum absolute errors of diastolic and systolic blood pressure were ±7/±10 mm Hg, respectively, in immobilized, and ±10/±14 mm Hg, respectively, in walking scenarios. These strategies provide advanced blood pressure monitoring techniques, which would directly address an unmet clinical need or daily use for a highly vulnerable population.  相似文献   
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周光礼  罗睿 《教育研究》2021,42(10):138-153
任何国家的学术系统都是分层的,根据名望和影响力对学者进行等级区分是一种普遍现象.在中国学术系统中,院士是位居金字塔塔尖的精英群体.无论在科学家的心目中,还是在一般公众的观念上,院士都是国内最具权威、最具声望、最具影响力的人才头衔.中国科学精英的生成过程是一个光环叠加的过程.一方面,精英人才通过对优质教育与科研资源的获取不断进行学术产出和科研能力等资本的累积.另一方面,在"马太效应"的作用机制下,机构的声望、名师效应、海外留学与科研经历、行政任职等因素也在其成长过程中产生不可忽视的影响.  相似文献   
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