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101.
娄维义 《生物学教学》2010,35(10):13-14
本文介绍了洛克菲勒大学对中学生物科技教师的培训方式和做法。该培训注重以教师科研经历促进科研指导,以师生共同培训示范科研指导,以专家科研报告引领科研指导,以同行交流促进科研指导。  相似文献   
102.
In this paper, the globally exponential synchronization problem of dynamical networks with nonlinearly coupling function is considered. Hybrid pinning control strategies are established to force the states of the network to follow some objective trajectory. The impulsive pinning controllers are used to control a fringe of nodes at the impulsive instants, while during the impulsive instants, pinning state-feedback controllers are designed to achieve the control objective. Finally, the validity of the developed techniques is evidenced by an illustrative example.  相似文献   
103.
The issue of sports mascot loyalty, especially to those mascots considered offensive, was investigated through fan identification theory, and applied to the mascot controversy at a large university in the United States. Replicating a previous university survey on the mascot question, a survey of current university students (N = 3616) revealed a strong relationship between mascot loyalty and fan identification, particularly related to one’s perceptions of ‘belonging to the university sports family’, and ‘associating with sports fans’ of the university. Other important findings include age differences and the marginalization of Asian-American fans. The implications and applications of these findings were discussed.  相似文献   
104.
旅游信息服务生态链模型及其协同管理研究   总被引:1,自引:0,他引:1  
覃子珍  娄策群 《现代情报》2017,37(12):19-23
[目的/意义]基于信息服务生态视角,研究旅游信息服务生态链模型及其协同管理,以期为提高旅游信息服务质量及效率提供参考。[方法/过程]文章首先论述了旅游信息服务生态链的基本概念及其特点,其次对旅游信息服务生态链的构成要素进行分析并构建模型,最后从链内和链间两个维度探讨旅游信息服务生态链的协同管理。[结果/结论]通过旅游信息服务生态链模型及其协同管理进行研究,为提高旅游信息服务质量和效率提供参考。  相似文献   
105.
声品质概念的提出,对噪声控制提出了不仅要降低噪声级,还要能够调节声音特性的要求,因此对声品质进行准确的评价非常重要。声品质以人的主观感受作为最终的评判标准,但目前所有的仪器都无法直接测量人的听觉数值,必须借助于心理声学客观参量进行描述。主观评价和心理客观参量相结合,建立数学模型进行分析计算,得到较准确的声品质评价结果,为噪声主动控制技术的发展提供了理论基础。  相似文献   
106.
探讨在信息生态系统中信息人相互作用的范围、纽带、方式和效果。指出相互作用范围包括种内相互作用和种间相互作用,相互作用的纽带主要有信息资源流转和信息资源共建共享,竞争和合作是信息人相互作用的两种基本方式,相互作用效果类型多样且分布具有偏利、偏害、同质互利、异质互利、同质互害、异质互害等多种情况。  相似文献   
107.
108.
We report that a 63-year-old Chinese female had acute myeloblastic leukemia (AML) in which trisomy 21 (+21) was found as the sole acquired karyotypic abnormality. The blasts were positive for myeloperoxidase, and the immunophenotype was positive for cluster of differentiation 19 (CD19), CD33, CD34, and human leukocyte antigens (HLA)-DR. The chromosomal analysis of bone marrow showed 47,XX,+21[2]/46,XX[18]. Fluorescent in situ hybridization (FISH) showed that three copies of AML1 were situated in separate chromosomes, and that t(8;21) was negative. The patient did not have any features of Down syndrome. A diagnosis of CD19-positive AML-M5 was established with trisomy 21 as a sole acquired karyotypic abnormality. The patient did not respond well to chemotherapy and died three months after the diagnosis. This is the first reported case of CD19-positive AML with trisomy 21 as the sole cytogenetic abnormality. The possible prognostic significance of the finding in AML with +21 as the sole acquired karyotypic abnormality was discussed.  相似文献   
109.
Abstract

The decay of the memory trace for intervals of 1/2 min., 1 1/2 min., and 4 min. between the test stimulus and the reproduction trial was studied for a force reproduction task in which the amount of movement was very small, .13 in. The subject pushed against a handle attached to the top of a steel bar with the preferred hand. Sixty-three women volunteers from college physical education classes performed the experiment. For Part A all subjects first had four trials in which the reproduction was immediate (the control condition). Then they were divided randomly into three subgroups of 21, and each subgroup was assigned to one of the three retention intervals (experimental conditions) for four more trials. In Part B the whole experiment was repeated. For both absolute and algebraic error, analysis of covariance indicated no significant differences at the .05 level among the experimental conditons. Also, no significant differences were found comparing a condition in Part A with its respective condition in Part B. While there were no significant differences between control and experimental conditions for absolute error, significant differences were found for algebraic error. The algebraic error changed from considerable overestimation upon immediate reproduction to only slight overestimation after a 1/2-min. retention interval.  相似文献   
110.
Abstract

The effect of practice on individual differences and intra-individual variability in reaction and movement times were studied for simple and complex, discrete, motor tasks. Changes with practice for intertrial correlations of adjacent trials and the effects of an increasing number of interpolated trials on intertrial correlations were also observed. For both tasks and for both reaction and movement times, the intra-individual variability decreased with practice. The true score variability for reaction time on both tasks and for movement time on the simple task shows little change with practice. On the complex task, true score variability for movement time decreases with practice. For movement time, adjacent trial correlations increase during the early practice trials then remain stable. For reaction time adjacent trial correlations increase throughout practice. Remoteness effects on intertrial correlations were found for both movement and reaction times for both tasks.  相似文献   
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