Identifying natural genotypes of grain number per panicle in rice (Oryza sativa L.) by association mapping

Jianyin Xie,Fengmei Li,Najeeb Ullah Khan,Xiaoyang Zhu,Xueqiang Wang,Zhifang Zhang,Xiaoqian Ma,Yan Zhao,Quan Zhang,Shuyang Zhang,Zhanying Zhang,Jinjie Li,Zichao Li,Hongliang Zhang 한국유전학회 2019 Genes & Genomics Vol.41 No.3

Introduction As one of the main yield components, grain number per panicle (GNP) played critical role in the rice yield improvement. The identification of natural advantageous variations under different situations will promote the sustainable genetic improvement in rice yield. Objectives This study was designed to identify natural genotypes in a rice mini-core collection, to examine the genotypic effects across the indica and japonica genetic background in different environments, and excavating the superior genotypes that had drove the modern genetic improvement. Methods The association mapping of GNP was carried out using a mini-core collection including 154 indica and 119 japonica accessions in seven different environments. Genotypic effects of each genotype for each QTL were calculated and genotype frequency distortion between the commercial rice cultivars and landraces was screened by χ2-test. Results In total, 74 QTLs containing stable and sensitive QTLs in various environments were detected. Within them, 20 positive and 24 negative genotypes in indica, and 24 positive and 16 negative genotypes in japonica were identified. When checking the accumulation of positive genotypes identified in indica across cultivars in each of the two subspecies, it indicated that increased number of positive genotypes identified in indica results in the substantially increased GNP in both indica and japonica across all of the environments, while this trend was not obvious for the positive genotypes identified in japonica especially in short day environments. Moreover, the positive and negative genotype frequency distortion between the landraces and commercial rice cultivars indicated that both positive selection of positive genotypes and negative selection of negative genotypes had driven the genetic improvement on GNP. Conclusion Our findings suggested that the accumulation of positive genotypes and purifying negative genotypes played equivalently important roles in the improvement of rice yield, but the efficient use for some QTLs or genotypes depends on the comprehensive evaluation of their effect under diverse genetic backgrounds and environments.

Optimization of long span portal frames using spatially distributed surrogates

Zhifang Zhang,Jingwen Pan,Jiyang Fu,Hemant Kumar Singh,Yong-Lin Pi,Jiurong Wu,Rui Rao 국제구조공학회 2017 Steel and Composite Structures, An International J Vol.24 No.2

This paper presents optimization of a long-span portal steel frame under dynamic wind loads using a surrogate-assisted evolutionary algorithm. Long-span portal steel frames are often used in low-rise industrial and commercial buildings. The structure needs be able to resist the wind loads, and at the same time it should be as light as possible in order to be cost-effective. In this work, numerical model of a portal steel frame is constructed using structural analysis program (SAP2000), with the web-heights at five locations of I-sections of the columns and rafters as the decision variables. In order to evaluate the performance of a given design under dynamic wind loading, the equivalent static wind load (ESWL) is obtained from a database of wind pressures measured in wind tunnel tests. A modified formulation of the problem compared to the one available in the literature is also presented, considering additional design constraints for practicality. Evolutionary algorithms (EA) are often used to solve such non-linear, black-box problems, but when each design evaluation is computationally expensive (e.g., in this case a SAP2000 simulation), the time taken for optimization using EAs becomes untenable. To overcome this challenge, we employ a surrogate-assisted evolutionary algorithm (SAEA) to expedite the convergence towards the optimum design. The presented SAEA uses multiple spatially distributed surrogate models to approximate the simulations more accurately in lieu of commonly used single global surrogate models. Through rigorous numerical experiments, improvements in results and time savings obtained using SAEA over EA are demonstrated.

Fumigant Activity of Volatiles from Streptomyces alboflavus TD-1 against Fusarium moniliforme Sheldon

Zhifang Wang,Changlu Wang,Fengjuan Li,Zhenjing Li,Mianhua Chen,Yurong Wang,Xi Qiao,Hong Zhang 한국미생물학회 2013 The journal of microbiology Vol.51 No.4

The fumigant activity of volatiles generated by Streptomyces alboflavus TD-1 against Fusarium moniliforme Sheldon was investigated. The results showed that the mycelial growth,sporulation, and spore germination of F. moniliforme were significantly suppressed, and that membrane permeability was disrupted in the presence of the volatiles. Gas chromatography-mass Spectrometry analysis revealed 31 kinds of volatile organic compound from the volatiles. Among them,two earthy-smelling substances, namely, 2-methylisoborneol (50.97%) and trans-1,10-dimethyl-trans-9-decalinol (3.10%)were found. The most abundant compound, 2-methylisoborneol,exhibited inhibitory activity against F. moniliforme by fumigation. All these results suggested that S. alboflavus TD-1 can be a promising starter for the inhibition of F. moniliforme through fumigant action.

Phylogenetic Analysis on the Bacteria Producing Non-Volatile Fungistatic Substances

ZhiFang Li,ChangSong Zou,YueQiu He,MingHe Mo,KeQin Zhang 한국미생물학회 2008 The journal of microbiology Vol.46 No.3

This study characterized the soil bacteria producing non-volatile fungistatic substances. Among the 2,100 colonies of soil bacteria randomly isolated from seven agricultural soil samples, 518 isolates (24.67% of total) showed fungistatic activity toward nematophagous fungi Paecilomyces lilacinus and Trichoderma viride by producing non-volatile substances. A phylogenetic analysis based on amplified ribosomal DNA restriction analysis (ARDRA) and 16S rDNA sequence placed the 518 bacteria in three groups of the domain Bacteria: Actinomycetales, Bacillales, and Gammaproteobacteria. Three genera, Arthrobacter, Bacillus, and Pseudomonas, were the most frequently encountered groups.

Soft-Switching Single-Stage Current-Fed Full-Bridge Isolated Converter for High Power AC/DC Applications

Yu Zhang,Chushan Li,Zhifang Cao,David Xu 전력전자학회 2015 ICPE(ISPE)논문집 Vol.2015 No.6

In this paper, a novel single-stage softswitching current-fed full-bridge AC/DC converter is proposed. By adding an additional commutation path, softswitching can be realized for all power devices. The power density is also enhanced by eliminating the DC capacitor. Meanwhile, the conduction loss is also lowered through the use of the additional commutation path. Furthermore, the control strategy for the proposed converter is compatible with that for traditional PFC converter. This facilitates the use of well-developed analog control IC such as UC3854. In this paper, the topology derivation and circuit operational analysis are given. The control strategy is introduced. A simulation is carried out to verify the circuit functionality.

TNF-α-Induced SOX5 Upregulation Is Involved in the Osteogenic Differentiation of Human Bone Marrow Mesenchymal Stem Cells Through KLF4 Signal Pathway

Lijun Xu,Lili Zheng,Zhifang Wang,Chong Li,Shan Li,Xuedi Xia,Pengyan Zhang,Li Li,Lixia Zhang 한국분자세포생물학회 2018 Molecules and cells Vol.41 No.6

Postmenopausal osteoporosis (PMOP) is a common sys-temic skeletal disease characterized by reduced bone mass and microarchitecture deterioration. Although differentially expressed SOX5 has been found in bone marrow from ovariectomized mice, its role in osteogenic differentiation in human mesenchymal stem cells (hMSCs) from bone marrow in PMOP remains unknown. In this study, we investigated the biological function of SOX5 and explore its molecular mechanism in hMSCs from patients with PMOP. Our findings showed that the mRNA and protein expression levels of SOX5 were upregulated in hMSCs isolated from bone marrow samples of PMOP patients. We also found that SOX5 overexpression decreased the alkaline phosphatase (ALP) activity and the gene expression of osteoblast markers including Collagen I, Runx2 and Osterix, which were increased by SOX5 knockdown using RNA interference. Furthermore, TNF- notably upregulated the SOX5 mRNA expression level, and SOX5 knockdown reversed the effect of TNF- on osteogenic differentiation of hMSCs. In addition, SOX5 overexpression increased Kruppel-like factor 4 (KLF4) gene expression, which was decreased by SOX5 silencing. KLF4 knockdown abrogated the suppressive effect of SOX5 overexpression on osteogenic differentiation of hMSCs. Taken together, our results indicated that TNF--induced SOX5 upregulation inhibited osteogenic differentiation of hMSCs through KLF4 signal pathway, suggesting that SOX5 might be a novel therapeutic target for PMOP treatment.

A General Self-Propagating High-Temperature Synthesis Method for Fast and Easy Preparation of Metal Oxide Nanostructures from Low Melting Point Metals

Nian Liu,Guodong Zhang,Yadong Xiao,Zhifang Peng 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2015 NANO Vol.10 No.1

Different metal oxide nanostructures including SnO2 nanowires, SnO2 nanoparticles, ZnO nanorods, ZnO nanoparticles, Al2O3 nanoparticles, SiO2 nanoarray, and SnO2–SiO2 core–shell nanoparticles, can be selectively synthesized by Self-propagating High-temperature Synthesis (SHS) method with different reaction systems. This method can be easily applied to synthesize metal oxide nanostructures with high yield and excellent purity from low melting point metals in a very short time at low cost without the need for any sophisticated equipment. The composition of reaction system has a crucial influence on the reaction temperature and morphology of the end products. Compared with nanoparticles, nanowires or nanorods can be obtained at lower reaction temperature. And introducing the chemical containing silicon to the reaction system allows the formation of SiO2 nanoarray and SnO2–SiO2 core–shell nanoparticles.

Zero-Voltage and Zero-Current Switching Interleaved Two-Switch Forward Converter

Enhui Chu,Jianqun Bao,Qi Song,Yang Zhang,Haolin Xie,Zhifang Chen,Yue Zhou 전력전자학회 2019 JOURNAL OF POWER ELECTRONICS Vol.19 No.6

In this paper, a novel zero-voltage and zero-current switching (ZVZCS) interleaved two switch forward converter is proposed. By using a coupled-inductor-type smoothing filter, a snubber capacitor, the parallel capacitance of the leading switches and the transformer parasitic inductance, the proposed converter can realize soft-switching for the main power switches. This converter can effectively reduce the primary circulating current loss by using the coupled inductor and the snubber capacitor. Furthermore, this converter can reduce the reverse recovery loss, parasitic ringing and transient voltage stress in the secondary rectifier diodes caused by the leakage inductors of the transformer and the coupled inductance. The operation principle and steady state characteristics of the converter are analyzed according to the equivalent circuits in different operation modes. The practical effectiveness of the proposed converter was is illustrated by simulation and experimental results via a 500W, 100 kHz prototype using the power MOSFET.

TNF-α-Induced SOX5 Upregulation Is Involved in the Osteogenic Differentiation of Human Bone Marrow Mesenchymal Stem Cells Through KLF4 Signal Pathway

Xu, Lijun,Zheng, Lili,Wang, Zhifang,Li, Chong,Li, Shan,Xia, Xuedi,Zhang, Pengyan,Li, Li,Zhang, Lixia Korean Society for Molecular and Cellular Biology 2018 Molecules and cells Vol.41 No.6

Postmenopausal osteoporosis (PMOP) is a common systemic skeletal disease characterized by reduced bone mass and microarchitecture deterioration. Although differentially expressed SOX5 has been found in bone marrow from ovariectomized mice, its role in osteogenic differentiation in human mesenchymal stem cells (hMSCs) from bone marrow in PMOP remains unknown. In this study, we investigated the biological function of SOX5 and explore its molecular mechanism in hMSCs from patients with PMOP. Our findings showed that the mRNA and protein expression levels of SOX5 were upregulated in hMSCs isolated from bone marrow samples of PMOP patients. We also found that SOX5 overexpression decreased the alkaline phosphatase (ALP) activity and the gene expression of osteoblast markers including Collagen I, Runx2 and Osterix, which were increased by SOX5 knockdown using RNA interference. Furthermore, $TNF-{\alpha}$ notably upregulated the SOX5 mRNA expression level, and SOX5 knockdown reversed the effect of $TNF-{\alpha}$ on osteogenic differentiation of hMSCs. In addition, SOX5 overexpression increased Kruppel-like factor 4 (KLF4) gene expression, which was decreased by SOX5 silencing. KLF4 knockdown abrogated the suppressive effect of SOX5 overexpression on osteogenic differentiation of hMSCs. Taken together, our results indicated that $TNF-{\alpha}$-induced SOX5 upregulation inhibited osteogenic differentiation of hMSCs through KLF4 signal pathway, suggesting that SOX5 might be a novel therapeutic target for PMOP treatment.

Zero-Voltage and Zero-Current Switching Interleaved Two-Switch Forward Converter

Chu, Enhui,Bao, Jianqun,Song, Qi,Zhang, Yang,Xie, Haolin,Chen, Zhifang,Zhou, Yue The Korean Institute of Power Electronics 2019 JOURNAL OF POWER ELECTRONICS Vol.19 No.6

In this paper, a novel zero-voltage and zero-current switching (ZVZCS) interleaved two switch forward converter is proposed. By using a coupled-inductor-type smoothing filter, a snubber capacitor, the parallel capacitance of the leading switches and the transformer parasitic inductance, the proposed converter can realize soft-switching for the main power switches. This converter can effectively reduce the primary circulating current loss by using the coupled inductor and the snubber capacitor. Furthermore, this converter can reduce the reverse recovery loss, parasitic ringing and transient voltage stress in the secondary rectifier diodes caused by the leakage inductors of the transformer and the coupled inductance. The operation principle and steady state characteristics of the converter are analyzed according to the equivalent circuits in different operation modes. The practical effectiveness of the proposed converter was is illustrated by simulation and experimental results via a 500W, 100 kHz prototype using the power MOSFET.