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111.
报道了重组家蚕核多角体病毒(BombyxmorinuclearPolyhedrosisVirusBmNPV)在家蚕细胞BmN中复制的细胞病理学变化,除了不形成多角体以外,与野生型病毒相同.研究了病毒感染复数、细胞接种密度和细胞生长阶段对重组病毒复制和α-干扰素(IFN-α)表达量的影响.在一定低感染复数时,α-干扰素的产量较高.对于重组病毒的复制,最适的细胞接种密度为3.6~7.0×105细胞/瓶.在细胞指数生长前期(48~60h)接种重组病毒,对于获得较高的重组病毒复制效价和α-干扰素的产量都是有利的.  相似文献   
112.
近江牡蛎受精细胞学研究   总被引:5,自引:0,他引:5  
用醋酸──地衣红染色的方法对近江牡蛎人工授精的卵子减数分裂和受精过程进行了详细的细胞学观察.精子入卵前,卵子处于第一次减数分裂的前期(胚泡期),精子入卵后,胚泡消失,然后进行两次减数分裂,在海水温度为28.8℃的情况下,授精后33min和45min,绝大部分受精卵已排出第一极体和第二极体,雄原核可在第一极体排出后及第二极体排出前任何时期内形成,雌雄原核以联合的方式将两组染色体合并,授精后1h,大部分卵子完成第一次卵裂.在25℃和26℃授精的情况下,观察到了较多的多精入卵的现象.卵子发育的非同步性现象非常明显.  相似文献   
113.
大型建筑工程项目在进行投资方案经济评价时,通常采用内部收益法与净现值法,在某些情况下,这两种分析法的结论可能出现不一致性,本文对此进行了深入讨论,并阐述了如何根据投资项目的特点进行有针对性的选择应用,以供对建筑工程项目投资方案评价时参考。  相似文献   
114.
We propose and analyze an interface between a topological qubit and a superconducting flux qubit. In our scheme, the interaction between Majorana fermions in a topological insulator is coherently controlled by a superconducting phase that depends on the quantum state of the flux qubit. A controlled-phase gate, achieved by pulsing this interaction on and off, can transfer quantum information between the topological qubit and the superconducting qubit.  相似文献   
115.

Background

Trail-making tests, such as the Concept Shifting Task (CST), can be used to test the effects of treatment on cognitive performance over time in various neuropsychological disorders. However, cognitive performance in such experimental designs might improve as a result of the practice obtained during repeated testing rather than the treatment itself. The current study investigated if practice affects the accuracy and duration of performance on the repeatedly administered Concept Shifting Task modified to make it resistant to practice (mCST). The mCST was administered to 54 healthy participants twice a day, before and after a short break, for eight days. Results. The ANOVA and meta-analysis showed that there was no improvement in the mCST accuracy on the last vs. the first trial (Hedges' g = .14, p = .221) or within the session (after vs. before the break on all days; g = .01, p = .922). However, the participants performed the task faster on the last vs. the first trial (g = -.75, p < .001) and after vs. before the break on all days (g = -.12, p = .002). Conclusions. Repeated administration of the mCST does not affect the accuracy of performance on the test. However, practice might contribute to faster performance on the mCST over time and within each session.  相似文献   
116.
With spin squeezing parameter we investigate the entangled property of a multipartite state superposed by three Dicke states with arbitrary relative phases. We first derive the mean spin direction, the optimally squeezed angle, and then numerically calculate the dependence of spin squeezing parameter on the superposition coefficients, the relative phases and the forms of the Dicke states. It’s shown that the entangled property depends on these parameters.  相似文献   
117.
The output spectrum-stability of Er-doped superfluorescent fiber source (SFS) was measured by changing the temperature around the excited Er-doped fiber (EDF). With the experiment results, the influences of the SFS's spectrum-stability on the signal-to-noise ratio (SNR) of fiber optic gyroscope (FOG) were simulated. The simulated results demonstrate that the SNR of FOG will change no matter the power, mean wavelength or the spectral bandwidth of the light output from the Er-doped SFS is changing. The results show that the changing of SNR caused by the output power's variation is three orders of magnitude larger than that caused by the variation of mean wavelength or bandwidth. And the main factor influencing the stability of FOG's SNR is the temperature-stability of the output power of Er-doped SFS.  相似文献   
118.
We present a review of our recent research in econophysics, and focus on the comparative study of Chinese and western financial markets. By virtue of concepts and methods in statistical physics, we investigate the time correlations and spatial structure of financial markets based on empirical high-frequency data. We discover that the Chinese stock market shares common basic properties with the western stock markets, such as the fat-tail probability distribution of price returns, the long-range auto-correlation of volatilities, and the persistence probability of volatilities, while it exhibits very different higher-order time correlations of price returns and volatilities, spatial correlations of individual stock prices, and large-fluctuation dynamic behaviors. Furthermore, multi-agent-based models are developed to simulate the microscopic interaction and dynamic evolution of the stock markets.  相似文献   
119.
l1-SPIRiT is a fast magnetic resonance imaging (MRI) method which combines parallel imaging (PI) with compressed sensing (CS) by performing a joint l1-norm and l2-norm optimization procedure. The original l1-SPIRiT method uses two-dimensional (2D) Wavelet transform to exploit the intra-coil data redundancies and a joint sparsity model to exploit the inter-coil data redundancies. In this work, we propose to stack all the coil images into a three-dimensional (3D) matrix, and then a novel 3D Walsh transform-based sparsity basis is applied to simultaneously reduce the intra-coil and inter-coil data redundancies. Both the 2D Wavelet transform-based and the proposed 3D Walsh transform-based sparsity bases were investigated in the l1-SPIRiT method. The experimental results show that the proposed 3D Walsh transform-based l1-SPIRiT method outperformed the original l1-SPIRiT in terms of image quality and computational efficiency.  相似文献   
120.
In this Letter, we report the effects of strain on the electronic properties of single-wall carbon nanotubes. When we normalize the electronic transition energies to the corresponding values obtained for unstrained tubes, we obtain that, regardless of the tube diameter, all the data collapse onto universal curves following an n - m = constant family pattern. In the case of metallic tubes, quantum interference effects on the Raman cross section are predicted for strained tubes when the energies of the lower and the upper components have nearly the same values. Experimental evidence for the strain-induced Raman cross section changes is observed in single nanotube spectroscopy.  相似文献   
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