In this paper the four-dimensional dynamic diffusing mechanism and the enhancement in Long-Term Potentiation (LTP) of intrinsic nitric oxide (NO) in nervous system are studied computationally. A novel unsupervised Diffusing Self-Organizing Maps (DSOM) model is presented on the union of SOM with NO diffusing mechanism. Based on the spatial prototype mapping, temporal enhancement is introduced in DSOM and the fine-tuning manner is improved by the simplified NO diffusing mechanism. Furthermore, the quantization error of optimal weights is valuated and the detailed noise analysis of DSOM is presented. Finally some typical stimulation experiments are presented to illustrate how DSOM gracefully handles time warping and multiple patterns with overlapping reference vectors.
A genetic linkage map consisting of 168 DNA markers was constructed based on a recombinant inbred line(RID population derived from a cross between a high yielding indica variety, Zhong156, and a low yielding indica variety, Gumeil. The markers on the linkage map were distributed on all 12 chromosomes and covered 1 447. 9 cM of the genome. The parents and 304 RILs were grown in China National Rice Research Institute(CNRRI), Hangzhou, China, in 2001, over two seasons in a randomized block design. The statistic software of QTL Mapper 1.01 was applied to detect quantitative trait loci(QTLs)and additive by environment(AE)interactions for yield traits, including panicle length, number of panicles per plant, number of spikelets per panicle, number of filled grains per panicle, fertility and kilo-grain weight. A total of 30 QTLs with significant additive effects located on all chromosomes, except chromosomes 5 and 9, and two QTLs with significant AE interactions, were detected. Thirty-one interactions of QTLs showing significant additive by additive epistatic effects for yield traits were also detected. Genetic contributions were generally lower for QTLs showing epistatic effects compared with QTLs showing additive effects. No significant interactions between epistasis and environment were detected.
CAO Li-yong, ZHAN Xiao-deng, ZHUANG Jie-yun, ZHENG Kang-le and CHENG Shi-hua(National Center for Rice Improvement, China National Rice Research Institute, Hangzhou 310006 , P. R. China)
A novel data processing procedure for fMRI was suggested in this paper, by which spatial and temporal characteristics of stimuli-induced signal dynamic responses can be investigated simultaneously. First the multitaper spectral estimation was utilized to estimate the spectrum of each voxel; the significance of the line frequency components at the interested frequency was tested to detect the task-related cortex areas; the temporal independent component analysis (tICA) was then applied to the activated voxels to obtain stimuli-induced signal dynamic responses. The advantages of this procedure are: few assumptions are needed for the cerebral hemodynamics and spatial distribution of task-related areas, problems which often appear in tICA analysis of fMRI data, such as the lack of stability, reliability and robustness, are overcome by the suggested method.
