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Hua W.,Shaanxi Normal University | Song J.,Shaanxi Normal University | Li C.,Shaanxi Normal University | Wang Z.,Shaanxi Normal University | Wang Z.,Shaanxi Institute of Education
Molecular Biology Reports | Year: 2012

Geranylgeranyl diphosphate (GGPP) synthase is an important branch point enzyme in terpenoid biosynthesis. It regulates the formation of diterpenoid, such as tanshinones. We cloned a gene for GGPP synthase SmGGPPs involved in diterpenoid biosynthesis from Salvia miltiorrhiza. At 2,767 bp long, this gene comprises an intron and two exons that encode a polypeptide of 364 amino acid residues. Then the 50 flanking sequence of SmGGPPs was characterized by bioinformatics method. Deletion analysis of the promoter of SmGGPPs using tobacco plant displayed that the promoter was induced by heat and cold. To further search these cis-elements involved in induction regulation in the 50 flanking sequence of SmGGPPs, many putative cis-elements were predicted with the PlantCARE and PLACE databases. A group of putative cis-acting elements are involved in induction regulation, including G-Box, WRKY, MYC and ATCT motifs. Real-time PCR analysis revealed that SmGGPPs is mainly expressed in the leaves and can also be induced by various factors, such as NaCl, wounding, high temperature, darkness, pathogen, methyl jasmonate, abscisic acid, salicylic acid, and gibberellins. This study provides useful information for further study of SmGGPPs and its regulator effect on the biosynthetic process of tanshinones so that researchers can improve the tanshinone contents in S. miltiorrhiza. © Springer Science+Business Media B.V. 2011.

Li G.,Shaanxi Institute of Education
Advanced Materials Research | Year: 2012

An efficient and robust star acquisition algorithm based on facet fitting is presented to improve the performance of star sensors. The location of star central pixels can be determined by searching extremum intensity pixels among the point spread function (PSF) of stars, which is well fitted by the cubic facet model. According to extremum theory, the second derivative operators are pre-calculated and the searching process can be completed using convolution operations thrice. Simultaneously, cluster formation is also a time consuming routine, which is accomplished using specific maximum and minimum threshold to speed up it. A variety of experiments are carried out to validate the performance of proposed algorithm, moreover, the performance evaluation index M is presented. The results clearly show that the proposed algorithm makes a great progress than the vector method in time expense and accuracy under intense noise conditions.© (2012) Trans Tech Publications, Switzerland.

Hu Z.,Shaanxi Institute of Education
Advances in Intelligent and Soft Computing | Year: 2011

The quality piano curriculum has been developed in many universities and colleges in China since its construction in 2006. I found some problems in many-year practical activities and thought it through, and studied the innovation mode of the quality piano curriculum on the basis of the status analysis on the quality piano curriculum of the senior normal universities and colleges to think that the passionate teaching is required for the quality piano curriculum and the modern media is necessary for constructing the piano teaching. So I put forward some viewpoints for how to innovate and construct the quality piano curriculum. © 2011 Springer-Verlag Berlin Heidelberg.

He M.,Shaanxi Normal University | Wang Y.,Northwest University, China | Hua W.,Shaanxi Institute of Education | Zhang Y.,Shaanxi Normal University | Wang Z.,Shaanxi Normal University
PLoS ONE | Year: 2012

Background: Hypericum perforatum L. (St. John's wort) is a medicinal plant with pharmacological properties that are antidepressant, anti-inflammatory, antiviral, anti-cancer, and antibacterial. Its major active metabolites are hypericins, hyperforins, and melatonin. However, little genetic information is available for this species, especially that concerning the biosynthetic pathways for active ingredients. Methodology/Principal Findings: Using de novo transcriptome analysis, we obtained 59,184 unigenes covering the entire life cycle of these plants. In all, 40,813 unigenes (68.86%) were annotated and 2,359 were assigned to secondary metabolic pathways. Among them, 260 unigenes are involved in the production of hypericin, hyperforin, and melatonin. Another 2,291 unigenes are classified as potential Type III polyketide synthase. Our BlastX search against the AGRIS database reveals 1,772 unigenes that are homologous to 47 known Arabidopsis transcription factor families. Further analysis shows that 10.61% (6,277) of these unigenes contain 7,643 SSRs. Conclusion: We have identified a set of putative genes involved in several secondary metabolism pathways, especially those related to the synthesis of its active ingredients. Our results will serve as an important platform for public information about gene expression, genomics, and functional genomics in H. perforatum. © 2012 He et al.

Li G.,Shaanxi Institute of Education | Li G.,University of Chinese Academy of Sciences
Guangxue Jishu/Optical Technique | Year: 2011

A novel centroid algorithm is proposed to acquire better stars centroid performance in star image based on Gaussian point spread function (PSF). As photons incident on pixels of stars presents the near Gaussian distribution, therefore, the centroid locations in x and y axis are calculated respectively utilizing the pixel intensity ratio and expand the Gaussian PSF to be polynomials with respect to the centroid location. The statistic of angular separation error between star pairs is used to indirectly verify the proposed algorithm. The result clearly shows that the centroid accuracy achieves 1/33 of a pixel and improves about 2 times than the moment method, which indicates the proposed algorithm is effective and convenient. Furthermore, the relation between the centroid position and the attitude accuracy is analyzed. The test result shows that the proposed centroid algorithm can improve the attitude accuracy of the camera significantly.

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