Super-Lift DC-DC Converters: Graphical Analysis and Modelling

Zhu, Miao,Luo, Fang Lin The Korean Institute of Power Electronics 2009 JOURNAL OF POWER ELECTRONICS Vol.9 No.6

Super-lift dc-dc converters are a series of advanced step-up dc-dc topologies that provide high voltage transfer gains by super-lift techniques. This paper presents a developed graphical modelling method for super-lift converters and gives a thorough analysis with a consideration of the effects caused by parasitic parameters and diodes' forward voltage drop. The general guidelines for constructing and deriving graphical models are provided for system analysis. By applying it to examples, the proposed method shows the advantages of high convenience and feasibility. Both the circuit simulation and experimental results are given to support the theoretical analysis.

Super-Lift DC-DC Converters: Graphical Analysis and Modelling

Miao Zhu,Fang Lin Luo 전력전자학회 2009 JOURNAL OF POWER ELECTRONICS Vol.9 No.6

Super-lift dc-dc converters are a series of advanced step-up dc-dc topologies that provide high voltage transfer gains by super-lift techniques. This paper presents a developed graphical modelling method for super-lift converters and gives a thorough analysis with a consideration of the effects caused by parasitic parameters and diodes’ forward voltage drop. The general guidelines for constructing and deriving graphical models are provided for system analysis. By applying it to examples, the proposed method shows the advantages of high convenience and feasibility. Both the circuit simulation and experimental results are given to support the theoretical analysis.

Extended Topologies of Tapped-Inductor Z-Source Inverters

Miao ZHU,Ding LI,Feng GAO,Poh Chiang LOH,Frede Blaabjerg 전력전자학회 2011 ICPE(ISPE)논문집 Vol.2011 No.5

In this paper, two distinct types of tapped-inductor Zsource impedance networks are proposed for implementing high-performance voltage-type inverters topologies with strong voltage boost inversion abilities and less components’ stresses. All proposed topologies can in principle be unified into a generic network entity, which is termed hybrid-source tapped-inductor impedance network. The resulting novel Z-source inverters would have a higher output voltage gain and other unique advantages that currently have not yet been investigated. Theoretical analysis for explaining these operating features has already been discussed throughout the paper, before experimental results are presented for verifying them. It is anticipated that these advantages would help the formed inverters find applications in photovoltaic and other renewable systems, where a high voltage gain is usually requested.

Polyphyllin I combined with doxorubicin shows chemosensitization effect in vivo and reduces immunotoxicity of doxorubicin

Zhu Xiang,Na Xin,Zeng Yueqin,Xu Yangantai,Chai Dongya,Yang Huanzhi,Miao Jingqian,Zhang Yuan,Yang Fenghua,Wang Yuehu,Zhou Yiping 대한독성 유전단백체 학회 2022 Molecular & cellular toxicology Vol.18 No.3

Background Polyphyllin I (PPI), a steroidal saponin, exhibits antitumor activity and chemosensitization effect for a broad spectrum of cancer cells, however, its toxicity and chemosensitization effect in vivo is still unknown. Objective We investigated PPI’s cytotoxic activity, toxicity and chemosensitization effect and in vitro and in vivo . Results The IC 50 values of PPI on MCF-7, H22, and S180 tumor cells were 4.37 μmol/L, 1.71 μmol/L, and 0.92 μmol/L, respectively. The LD 50 of PPI was found to be 47.9 mg/kg using ip. injection. PPI at concentrations of 0.3 mg/kg, 0.6 mg/ kg, 1.2 mg/kg, and 2.4 mg/kg (1/80 LD 50 –1/20 LD 50 ) were synergized with DOX of 0.5 mg/kg to inhibit the H22 and S180 tumor growth in vivo by inducing apoptosis without obvious immunotoxicity. PPI exhibited a remarkable hemolytic effect on rabbit erythrocytes (EC 50 = 4.3 μM), while it had no impact in mice. Conclusion Our study revealed that the PPI-sensitized chemotherapeutic effect, when used in safe doses, circumvents immunotoxic side effects of DOX in vivo; thus, helping future clinical research.

Ovarian transcriptomic analysis of Shan Ma ducks at peak and late stages of egg production

Zhu, ZhiMing,Miao, ZhongWei,Chen, HongPing,Xin, QingWu,Li, Li,Lin, RuLong,Huang, QinLou,Zheng, NenZhu Asian Australasian Association of Animal Productio 2017 Animal Bioscience Vol.30 No.9

Objective: To assess the differences in ovarian transcriptomes in Shan Ma ducks between their peak and late stages of egg production, and to obtain new transcriptomic data of these egg-producing ducks. Methods: The Illumina HiSeq 2000 system was used for high throughput sequencing of ovarian transcriptomes from Shan Ma ducks at their peak or late stages of egg production. Results: Greater than 93% of the sequencing data had a base quality score (Q score) that was not less than 20 (Q20). From ducks at their peak stage of egg production, 42,782,676 reads were obtained, with 4,307,499,083 bp sequenced. From ducks at their late stage of egg production, 45,316,166 reads were obtained, with 4,562,063,363 bp sequenced. A comparison of the two datasets identified 2,002 differentially expressed genes, with 790 upregulated and 1,212 downregulated. Further analysis showed that 1,645 of the 2,002 differentially expressed genes were annotated in the non-redundant (NR) database, with 646 upregulated and 999 downregulated. Among the differentially expressed genes with annotations in the NR database, 696 genes were functionally annotated in the clusters of orthologous groups of proteins database, involving 25 functional categories. One thousand two hundred four of the differentially expressed genes with annotations in the NR database were functionally annotated in the gene ontology (GO) database, and could be divided into three domains and 56 categories. The three domains were cellular component, molecular function, and biological process. Among the genes identified in the GO database, 451 are involved in development and reproduction. Analysis of the differentially expressed genes with annotations in the NR database against the Kyoto encyclopedia of genes and genomes database revealed that 446 of the genes could be assigned to 175 metabolic pathways, of which the peroxisome proliferator-activated receptor signaling pathway, insulin signaling pathway, fructose and mannose metabolic pathways, gonadotropin releasing hormone signaling pathway and transforming growth factor beta signaling pathway were significantly enriched. Conclusion: The differences in ovarian transcriptomes in Shan Ma ducks between their peak and late stages of egg production were elucidated, which greatly enriched the ovarian transcriptomic information of egg-producing ducks.

An Improved MMC Control Strategy with Single-Phase to Ground Fault-Tolerance Capability

Miao, Huiyu,Mei, Jun,Zheng, Jianyong,Zhang, Chenyu,Zhu, Chao,Ma, Tian,Mei, Fei The Korean Institute of Electrical Engineers 2016 Journal of Electrical Engineering & Technology Vol.11 No.5

In vitro fermentation profiles of different soybean oligosaccharides and their effects on skatole production and cecal microbiota of broilers

Zhu Xin,Xu Miao,Liu Haiying,Yang Guiqin 아세아·태평양축산학회 2022 Animal Bioscience Vol.35 No.8

Objective: The objective of this study was to investigate the in vitro fermentation profiles of different soybean oligosaccharides (SBOs) and their effects on skatole production and cecal microbiota of broilers. Methods: Five SBOs with varying main component contents were fermented using an in vitro batch incubation inoculated with broiler cecal microbiota. Gas production was recorded automatically, skatole, indole and short-chain fatty acids (SCFAs) were determined using high-performance liquid chromatography, and microbial changes were analyzed using 16S DNA gene sequencing. Results: The addition of SBOs increased (p<0.05) gas production, suggesting bacterial growth-stimulating activities. In addition, the concentrations of indole were significantly (p<0.05) decreased after SBO supplementation, and SBO III, with higher sucrose and stachyose contents, decreased (p<0.05) the skatole level. Our results also revealed that the fermentation of SBOs by cecal microbiota produced (p<0.05) SCFAs, which were dominated by propionic acid, butyrate acid and lactic acid compared to the control. In addition, SBO III increased (p<0.05) the abundance of Firmicutes and Subdoligranulum and decreased that of Bacteroides. Conclusion: These results suggest that SBOs with higher sucrose and stachyose contents are promising prebiotics in modulating gut microbiota and reducing odor emission in broilers. Objective: The objective of this study was to investigate the <i>in vitro</i> fermentation profiles of different soybean oligosaccharides (SBOs) and their effects on skatole production and cecal microbiota of broilers.Methods: Five SBOs with varying main component contents were fermented using an <i>in vitro</i> batch incubation inoculated with broiler cecal microbiota. Gas production was recorded automatically, skatole, indole and short-chain fatty acids (SCFAs) were determined using high-performance liquid chromatography, and microbial changes were analyzed using 16S DNA gene sequencing.Results: The addition of SBOs increased (p<0.05) gas production, suggesting bacterial growth-stimulating activities. In addition, the concentrations of indole were significantly (p<0.05) decreased after SBO supplementation, and SBO III, with higher sucrose and stachyose contents, decreased (p<0.05) the skatole level. Our results also revealed that the fermentation of SBOs by cecal microbiota produced (p<0.05) SCFAs, which were dominated by propionic acid, butyrate acid and lactic acid compared to the control. In addition, SBO III increased (p<0.05) the abundance of Firmicutes and <i>Subdoligranulum</i> and decreased that of <i>Bacteroides</i>.Conclusion: These results suggest that SBOs with higher sucrose and stachyose contents are promising prebiotics in modulating gut microbiota and reducing odor emission in broilers.

Bioactive Compounds / Food Microbiology : Improvement of Natamycin Production by Cholesterol Oxidase Overexpression in Streptomyces gilvosporeus

( Miao Wang ),( Shao Hua Wang ),( Gong Li Zong ),( Zhong Wen Hou ),( Fei Liu ),( D Joshua Liao ),( Xi Qiang Zhu ) 한국미생물 · 생명공학회 2016 Journal of microbiology and biotechnology Vol.26 No.2

Natamycin is a widely used antifungal antibiotic. For natamycin biosynthesis, the gene pimE encodes cholesterol oxidase, which acts as a signalling protein. To confirm the positive effect of the gene pimE on natamycin biosynthesis, an additional copy of the gene pimE was inserted into the genome of Streptomyces gilvosporeus 712 under the control of the ermE* promoter (permE*) using intergeneric conjugation. Overexpression of the target protein engendered 72% and 81% increases in the natamycin production and cell productivity, respectively, compared with the control strain. Further improvement in the antibiotic production was achieved in a 1 L fermenter to 7.0 g/l, which was a 153% improvement after 120 h cultivation. Exconjugants highly expressing pimE and pimM were constructed to investigate the effects of both genes on the increase of natamycin production. However, the co-effect of pimE and pimM did not enhance the antibiotic production obviously, compared with the exconjugants highly expressing pimE only. These results suggest not only a new application of cholesterol oxidase but also a useful strategy to genetically engineer natamycin production.

High-throughput sequencing analysis of differences in intestinal microflora between ulcerative colitis patients with different glucocorticoid response types

Yunzhen Zhu,Juan Luo,Zhaoqing Yang,Yinglei Miao 한국유전학회 2020 Genes & Genomics Vol.42 No.10

Background Previous investigations reported that the imbalance of intestinal microfora may be the initiation and promotion factor in the pathogenesis of infammatory bowel disease such as ulcerative colitis (UC). Glucocorticoid is a very important class of regulatory molecules in the body. The response of diferent individuals to glucocorticoids can be divided into glucocorticoid sensitive, glucocorticoid resistance and glucocorticoid dependence. Objective We aimed to investigate the diferences in intestinal microfora composition and related metabolic pathways in UC patients with these three diferent glucocorticoid response types. Methods The whole genomic DNA was extracted from fecal specimens. High-throughput sequencing technology was used to analyze the fecal 16S rRNA genome of UC patients with diferent glucocorticoid response types, and functional prediction was performed by PICRUSTs software. Results The results showed that the intestinal microfora of the three groups were mainly composed of Firmicutes, Proteobacteria and Bacteroidetes. Although the species abundance and diversity of intestinal microfora in UC patients difered little among the three groups, the composition of intestinal microfora showed signifcant heterogeneity, which directly led to diferences in the function of intestinal microbiota of UC patients with diferent glucocorticoid responses. Furthermore, of the 240 pathways, “PANTO-PWY: phosphopantothenate biosynthesis I”, “COA-PWY-1: coenzyme A biosynthesis II (mammalian)” and “PWY-4242: pantothenate and coenzyme A biosynthesis III” were signifcantly diferent in the three groups. Conclusions These results indicate that UC patients with diferent glucocorticoids response types have diferent bacterial compositions and functions, which lays a foundation for further study of glucocorticoid resistance in UC patients.

Influence of non-Gaussian characteristics of wind load on fatigue damage of wind turbine

Ying Zhu,Miao Shuang 한국풍공학회 2020 Wind and Structures, An International Journal (WAS Vol.31 No.3

Based on translation models, both Gaussian and non-Gaussian wind fields are generated using spectral representation method for investigating the influence of non-Gaussian characteristics and directivity effect of wind load on fatigue damage of wind turbine. Using the blade aerodynamic model and multi-body dynamics, dynamic responses are calculated. Using linear damage accumulation theory and linear crack propagation theory, crack initiation life and crack propagation life are discussed with consideration of the joint probability density distribution of the wind direction and mean wind speed in detail. The result shows that non-Gaussian characteristics of wind load have less influence on fatigue life of wind turbine in the area with smaller annual mean wind speeds. Whereas, the influence becomes significant with the increase of the annual mean wind speed. When the annual mean wind speeds are 7 m/s and 9 m/s at hub height of 90 m, the crack initiation lives under softening non-Gaussian wind decrease by 10% compared with Gaussian wind fields or at higher hub height. The study indicates that the consideration of the influence of softening non-Gaussian characteristics of wind inflows can significantly decrease the fatigue life, and, if neglected, it can result in non-conservative fatigue life estimates for the areas with higher annual mean wind speeds.