Genomics-based genetic understanding and improvement of hybrid rice

Qi Fa Zhang 한국육종학회 2002 한국육종학회 학술발표회 발표요지 Vol.34 No.2

SINGLE-PHASE-ENDED HIGH FREQUENCY SERIES RESONANT CONVERTER AND ITS APPLICATION IN INDUCTION HEATING AND ULTRASONIC WASHING

Jin-fa Zhang,Ying-qi Zhang 전력전자학회 1995 ICPE(ISPE)논문집 Vol.1995 No.10

This paper proposed and analyzed a new converter which has high power factor and also has high performance using PWM & PFM technique . AC line input cuneni is analyzed in detail during power regulation A novel phase-lock-loop ( PLL ) is presented to ensure normal operation condition of switches. Simulation of PLL under some typical conditions show its super characters. 25KHz and 100kHz induction heating system are designed separately as well as 25khz ultrasonic washing system.

COMPLEXITY OF CONTINUOUS SEMI-FLOWS AND RELATED DYNAMICAL PROPERTIES

Zhang, Feng,He, Lian-Fa,Lu, Qi-Shao Korean Mathematical Society 2009 대한수학회지 Vol.46 No.2

The equicontinuity and scattering properties of continuous semi-flows are studied on a compact metric space. The main results are obtained as follows: first, the complexity function defined by the spanning set is bounded if and only if the system is equicontinuous; secondly, if a continuous semi-flow is topologically weak mixing, then it is pointwise scattering; thirdly, several equivalent conditions for the time-one map of a continuous semi-flow to be scattering are presented; Finally, for a minimal continuous map it is shown that the "non-dense" requirement is unnecessary in the definition of scattering by using open covers.

Complexity of continuous semi-flows and related dynamical properties

Feng Zhang,Lian-Fa He,Qi-Shao Lu 대한수학회 2009 대한수학회지 Vol.46 No.2

The equicontinuity and scattering properties of continuous semi-flows are studied on a compact metric space. The main results are obtained as follows: first, the complexity function defined by the spanning set is bounded if and only if the system is equicontinuous; secondly, if a continuous semi-flow is topologically weak mixing, then it is pointwise scattering; thirdly, several equivalent conditions for the time-one map of a continuous semi-flow to be scattering are presented; Finally, for a minimal continuous map it is shown that the ``non-dense" requirement is unnecessary in the definition of scattering by using open covers. The equicontinuity and scattering properties of continuous semi-flows are studied on a compact metric space. The main results are obtained as follows: first, the complexity function defined by the spanning set is bounded if and only if the system is equicontinuous; secondly, if a continuous semi-flow is topologically weak mixing, then it is pointwise scattering; thirdly, several equivalent conditions for the time-one map of a continuous semi-flow to be scattering are presented; Finally, for a minimal continuous map it is shown that the ``non-dense" requirement is unnecessary in the definition of scattering by using open covers.

siRNA-mediated Silencing of Notch-1 Enhances Docetaxel Induced Mitotic Arrest and Apoptosis in PCa Cells

Ye, Qi-Fa,Zhang, Yi-Chuan,Peng, Xiao-Qing,Long, Zhi,Ming, Ying-Zi,He, Le-Ye Asian Pacific Journal of Cancer Prevention 2012 Asian Pacific journal of cancer prevention Vol.13 No.6

Purpose: Notch is an important signaling pathway that regulates cell fate, stem cell maintenance and the initiation of differentiation in many tissues. It has been reported that activation of Notch-1 contributes to tumorigenesis. However, whether Notch signaling might have a role in chemoresistance of prostate cancer is unclear. This study aimed to investigate the effects of Notch-1 silencing on the sensitivity of prostate cancer cells to docetaxel treatment. Methods: siRNA against Notch-1 was transfected into PC-3 prostate cancer cells. Proliferation, apoptosis and cell cycle distribution were examined in the presence or absence of docetaxel by MTT and flow cytometry. Expression of $p21^{waf1/cip1}$ and Akt as well as activation of Akt in PC-3 cells were detected by Western blot and Real-time PCR. Results: Silencing of Notch-1 promoted docetaxel induced cell growth inhibition, apoptosis and cell cycle arrest in PC-3 cells. In addition, these effects were associated with increased $p21^{waf1/cip1}$ expression and decreased Akt expression and activation in PC-3 cells. Conclusion: Notch-1 promotes chemoresistance of prostate cancer and could be a potential therapeutic target.

Experimental Study on Magnesium Sulfate Cement Concrete Splices of Widened Box Girder

Li-fang Zhang,Jun Yan,Hai-yan Ma,Hong-fa Yu,Ying Wang,Qi-quan Mei 대한토목학회 2021 KSCE JOURNAL OF CIVIL ENGINEERING Vol.25 No.12

The connecting part of bridge widening undertakes complicated forces and tends to crack. Basic magnesium sulfate cement concrete has excellent properties such as ideal early strength and tensile strength, meeting the performance requirements of joint materials. Experiments of two spliced box girder specimens with C40 basic magnesium sulfate cement concrete (MC) and normal Portland cement concrete (NC) as joint materials are carried out. Concrete strain, reinforcement strain, deflection and crack propagation law of the joint section are tested and analyzed under symmetrical loading at the cantilever of the box girders. The study shows when MC material is used in the splicing section, the joint section showed a multi-cracks failure mode with an ultimate load ratio of 0.99 and a maximum crack width of 1.3 mm; NC joint section has only three longitudinal cracks with an ultimate load ratio of 0.97 and a maximum crack width of 0.98 mm. Under the same load, the crack width and the deflection of mid-span MC joint section are greater than which of NC joint section. The maximum deflection of NC splicing section is 1.20 mm, which is 1/633 of the calculating span length. The maximum deflection of MC spliced section is 2.03 mm, which is 1/374 of the calculating span length. Comparison of the maximum deflection and the maximum crack width shows that MC material has better ductility.

Genomics Based Crop Germplasm Research

Ji Zeng Jia,Qi Fa Zhang 한국육종학회 2005 한국육종학회 학술발표회 발표요지 Vol.37 No.1

Fermentation Optimization and Industrialization of Recombinant Saccharopolyspora erythraea Strains for Improved Erythromycin A Production

Xiang Zou,Chang-fa Chen,Xia-chang Qi,Jiang-chao Qian,Ju Chu,Ying-ping Zhuang,Si-liang Zhang,Wei Zeng,Wan-jun Li 한국생물공학회 2010 Biotechnology and Bioprocess Engineering Vol.15 No.6

Improvement of Erythromycin A (Er-A) production and purity by metabolic engineering of the industrial erythromycin-producing strains Saccharopolyspora erythraea strians ZL1004 and ZL1007, in which the amounts of tailoring enzymes EryK (a P450 hydroxylase)and EryG (an S-adenosylmethionine-dependent O-methyltransferase)for biotransformation of Erythromycin D to Er-A were modulated, was performed in a 50 L fermentor. Addition of 15 g/L of corn steep liquor to the medium increased Er-A production; maximum Er-A production was 8,196 U/mL at 191 h, which was 81.8% higher than that of control (4,507 U/mL at 184 h). Er-B impurities were completely eliminated, whereas Er-C impurities were only 153 U/mL at 191 h. Analysis of intra- and extracellular metabolites and key enzyme activities in central carbon metabolism revealed that the pool of TCA cycle intermediates was enhanced by the addition of corn steep liquor and induced an increase in erythromycin biosynthesis. There were no significant differences between strains ZL1004 and ZL1007 regarding Er-A production and impurity accumulation. Compared to wild type strain,Er-A production was improved by 23.9% while Er-C was reduced by 83.9% and Er-B was completely eliminated. Furthermore, fermentation of recombinant strain ZL1004was successfully scaled up from laboratory scale (50 L fermentor) to industrial scale (25 and 132 m3), with similar levels of Er-A production and purity obtained.

Genetic variation and phylogenetic relationships of the ectomycorrhizal Floccularia luteovirens on the Qinghai-Tibet Plateau

Rui Xing,Qing-bo Gao,Fa-qi Zhang,Peng-cheng Fu,Jiu-li Wang,Hui-ying Yan,Shi-long-Chen 한국미생물학회 2017 The journal of microbiology Vol.55 No.8

Floccularia luteovirens, as an ectomycorrhizal fungus, is widely distributed in the Qinghai-Tibet Plateau. As an edible fungus, it is famous for its unique flavor. Former studies mainly focus on the chemical composition and genetic structure of this species. However, the phylogenetic relationship between genotypes remains unknown. In this study, the genetic variation and phylogenetic relationship between the genotypes of F. luteovirens in Qinghai-Tibet Plateau was estimated through the analysis on two protein-coding genes (rpb1 and ef-1α) from 398 individuals collected from 24 wild populations. The sample covered the entire range of this species during all the growth seasons from 2011 to 2015. 13 genotypes were detected and moderate genetic diversity was revealed. Based on the results of network analysis, the maximum likelihood (ML), maximum parsimony (MP), and Bayesian inference (BI) analyses, the genotypes H-1, H-4, H-6, H-8, H-10, and H-11 were grouped into one clade. Additionally, a relatively higher genotype diversity (average h value is 0.722) and unique genotypes in the northeast edge of Qinghai- Tibet plateau have been found, combined with the results of mismatch analysis and neutrality tests indicated that Southeast Qinghai-Tibet plateau was a refuge for F. luteovirens during the historical geological or climatic events (uplifting of the Qinghai-Tibet Plateau or Last Glacial Maximum). Furthermore, the present distribution of the species on the Qinghai-Tibet plateau has resulted from the recent population expansion. Our findings provide a foundation for the future study of the evolutionary history and the speciation of this species.