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81.
Previous investigations examining salient memories have demonstrated that personal memories that are important to individuals and contain emotional information are better remembered than neutral events.Using behavioral and brain-imaging experiments,the present studies explored whether the previous finding was applicable imagined loss.In a behavioral experiment,a free recall paradigm was used to compare the memory performance of individuals who imagined loss with that of individuals who imagined importance.The superior memory performance conferred by imagining loss was constrained to ordinary items of low to medium importance and did not generalize to vital items.Moreover,brain imaging evidence revealed that the activation in certain brain regions was stronger when participants were imagining the loss of ordinary items of low to medium importance compared to vital items.These brain regions included cognitive effort-related areas(such as the parietal cortex and middle prefrontal cortex) and areas related to emotional experiences and emotion-related memories(such as the amygdala,parahippocampal gyrus,and posterior cingulate gyrus).Our study provides a new way of exploring the superior memory performance when imagining loss and enriches the literature on memory enhancement by contributing to a deeper understanding of the psychological mechanisms related to the imagining of vital losses.  相似文献   
82.
定速失速型风力机功率控制策略改良研究   总被引:2,自引:0,他引:2  
为了提高风力发电系统综合系统性能, 在传统风力发电技术的基础上,对定速失速控制风力发电机组进行了详细的分析和研究,在Matlab下建立仿真模型,对其进行仿真分析,查看该型风力发电机性能的不足.在定速失速风力发电机的基础上,对其进行变速变浆距控制策略设计,建立数学模型进行仿真分析,分析结果表明经过改良设计后,风力发电机的风能利用效率和发电品质更高.为风力发电机控制系统改良设计提供了新的方法.  相似文献   
83.
The crystal structure stability as well as electric conductance of (Sr/Ca)2CuO2Cl2 compound with K2NiF4 structure was investigated up to 31 GPa using diamond anvil technique. It seems that (Sr/Ca)2CuO2Cl2 is quite stable under pressure but with obvious anisotropic compressibility. The equation of state (EOS) obtained shows relative large bulk modulus.  相似文献   
84.
The modified Hummers method was employed to generate graphene oxide, and Ag/reduced graphene oxide (RGO) nanocomposites were synthesized at different temperatures by using sodium citrate as the reductant. Scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and Raman spectroscopy were employed to characterize the reaction products. The results indicate that RGO has been synthesized successfully, and Ag particles are distributed evenly on the surface of RGO. The RGO prepared at a reaction temperature of 120℃ shows the best surface-enhanced Raman scattering (SERS) activity. The Ag/RGO nanocomposites modified by 10-5 mol/L 4-aminothiophenol (PATP) successfully detect a 10-5 mol/L 2,4,6-trinitrotoluene (TNT) alcohol solution.  相似文献   
85.
Due to its chemotaxis, the motion ability of bacterium BS2 is very strong, and under the microscope, the distribution grads of bacterium concentration can be seen at the oil-water interface. During the experiments in glass box, it can be observed, with eyes, because of the chemotaxis, that muddy gets thicker and thicker at the interface gradually, and it is measured there, from sampling, that the bacterium concentration is 10^9 cells/mL, pH value 4.4 and the concentration of bio-surfactant 2.87%; The microbial oil-displacement experiments are carried out in emulational network models, and the oil-displacement mechanism by the bacterium and its metabolizing production is studied. And, during oil-displacement experiments in the gravel-input glass models, because of the profile control of thalli and the production, the sweep area of subsequent waterflood becomes wider, which can be seen with eyes and the recovery is enhanced by 13.6%. Finally, the successful field test is introduced in brief: the ratio of response producers is 85.7%, and the water-cut degrades by 6.4%, while 20038t oil has increased in accumulative total in 2 years.  相似文献   
86.
We propose here a mathematical approach for the study of repairable systems with arbitrary distributions. The idea is to define a new type of stochastic process, called a generalized Markov renewal process (GMRP). which may describe the transition behavior of the stochastic process at non-regenerative points. In the paper an analytical method for the GMRP is put forward and the formulas are then presented for reliability analysis of repairable systems which can be described by a GMRP with finite states. A signal flow graph technique for system modeling is also summarized here. Finally- an analytical model to evaluate the reliability of a m-out-of- n.G system with general repair-time distribution is developed by means of the GMRP approach.  相似文献   
87.
88.
介绍全息术在测定悬臂梁受力变形位移量中的应用。  相似文献   
89.
An age-structured SEIR epidemic model of a vertically as well as horizontally transmitteddisease is investigated.Threshold results for the existence of endemic states are established for mostcases.Under certain conditions,uniqueness is also shown.Threshold used are explicitly computablein term of demographic and epidemiological parameters of the model.  相似文献   
90.
Prior studies have identified recurrent oncogenic mutations in colorectal adenocarcinoma and have surveyed exons of protein-coding genes for mutations in 11 affected individuals. Here we report whole-genome sequencing from nine individuals with colorectal cancer, including primary colorectal tumors and matched adjacent non-tumor tissues, at an average of 30.7× and 31.9× coverage, respectively. We identify an average of 75 somatic rearrangements per tumor, including complex networks of translocations between pairs of chromosomes. Eleven rearrangements encode predicted in-frame fusion proteins, including a fusion of VTI1A and TCF7L2 found in 3 out of 97 colorectal cancers. Although TCF7L2 encodes TCF4, which cooperates with β-catenin in colorectal carcinogenesis, the fusion lacks the TCF4 β-catenin-binding domain. We found a colorectal carcinoma cell line harboring the fusion gene to be dependent on VTI1A-TCF7L2 for anchorage-independent growth using RNA interference-mediated knockdown. This study shows previously unidentified levels of genomic rearrangements in colorectal carcinoma that can lead to essential gene fusions and other oncogenic events.  相似文献   
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