Power Distribution and Coordinated Control for a Power Split Hybrid Electric Bus

Feng Wang,Hu Zhong,Zi-Lin Ma,Xiao-Jian Mao,Bin Zhou 대한전기학회 2008 Journal of Electrical Engineering & Technology Vol.3 No.4

The power distribution is proposed to determine the target operating points of the system components as the basis for maximal the efficiency of the overall system for a power split dual electric machine hybrid electric bus. The coordinated control is constructed on the basis of the power distribution. The basic coordinated control is implemented to satisfy the driver's power demand, in which both the dynamic characteristics of the engine and the dual electric machine are explicitly taken into account. Moreover, the improved coordinated control is suggested to suppress engine dynamic operation and rich fuel injection.

Effects of different modification techniques on molecular structure and bioactivity of Bombyx mori pupa protein

Zhi-Feng Zhou,Zi-Xu Ren,Hai-Yan Yu,Jun-Qiang Jia,Zhong-Zheng Gui 한국응용곤충학회 2017 Journal of Asia-Pacific Entomology Vol.20 No.1

To improve the properties of silkworm (Bombyx mori) pupa protein (SPP), the effects of different modification techniques included enzymolysis, ultrasound, and micronization on the molecular structure and bioactivity of SPP has been evaluated in this study. The results showed that enzymolysis modification led to the most substantial change in the area and shape of the infrared (IR) absorption peaks, decreased in size with an increased number of cracks of modified protein by scanning electron microscopy images, followed by ultrasound and micronization modification. After modification by enzymolysis, ultrasound, and micronization, the sulfhydryl concentrations of SPPwere increased by 48.56%, 34.82%, and 12.46%, respectively; disulfide bond concentrations were reduced by 40.47%, 10.79%, and 11.72%, respectively. Furthermore, the ratios of essential amino acids among total amino acids increased by 13.85%, 2.22%, and 6.93%, respectively. Antioxidant activity and ACE-inhibitory activity of SPP also increased notably after modifications.

Selected microRNA-192 mutant indicates association with several function genes in bovine cells

Chen Zi,Dexin Zeng,Jiyong Zhou,Jianjun Dai,Luyan Jiang,Feng Xue,Yuan Jiang,Baoguang Li 한국유전학회 2018 Genes & Genomics Vol.40 No.4

MicroRNAs are implicated in many cellular processes such as cell differentiation and development, tumorigenesis, and immune regulation. In this study, miR192 was detected using quantitative real-time polymerase chain reaction (qRT-PCR) when MDBK cells were exposed to Escherichia coli. Cells with malfunction of bta-miR-192 were established using transcription activator-like effector nuclease (TALEN) technology. Finally, bta-miR-192 mutant cells were screened for differentially expressed genes using RNA-sequencing (RNA-seq). The results showed that miR192 significantly decreased in cells exposed to E. coli F18ac and E. coli K88ac. The RNA-seq results showed that 1673 differentially expressed transcripts were identified; 890 genes were upregulated and 775 genes were downregulated. With the gene ontology enrichment analysis, 431 differentially expressed genes (DEGs) were classified into 937 gene ontology terms. The pathway enrichment analysis showed that 535 genes were involved in 254 pathway terms. Interestingly, most of these DEGs were associated with the pathways in cancers or infectious diseases. When the selected DEGs (n = 162) in these pathways were intersected with 120 differential transcripts, 11 DEGs were identified. Subsequently, several genes associated with regulation, cancers, or viral infections, such as LEF1, AXIN2, MX1, and FCGR2B, were identified among the DEGs using functional analysis. Furthermore, associations between bta-miR-192 and DEGs were detected by intersecting the bta-miR-192’s target genes with the DEGs, indicating that three genes including CBL, DICER1 and TRERF1 were involved in this relationship. These findings provided useful guidance for investigating the role played by bta-miR-192 in cellular functionality in bovine cells.

Hexadecanoic Acid from Buzhong Yiqi Decoction Induced Proliferation of Bone Marrow Mesenchymal Stem Cells

Dong-Feng Chen,Xican Li,Zhiwei Xu,Xiaobing Liu,Shao-Hui Du,Hui Li,Jian-Hong Zhou,He-Ping Zeng,Zi-Chun Hua 한국식품영양과학회 2010 Journal of medicinal food Vol.13 No.4

Buzhong Yiqi decoction (BYD) is a well-known ancient tonic prescription in traditional Chinese medicine (TCM). The purpose of this study is to identify active components of BYD involved in promoting proliferation of mesenchymal stem cells (MSCs) and to investigate its mechanism. BYD was extracted with petroleum ether, ethanol, and water. Evidence provided by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide, bromodeoxyuridine, proliferation cell nuclear antigen immunoreactivity, cell cycle analysis, and gas chromatography-mass spectrometry indicated that hexadecanoic acid (HA) in BYD extracted with petroleum ether is the active compound responsible for increasing proliferation of MSCs. Western blot analysis show that HA significantly increase retinoic acid receptor (RAR) levels of MSCs, but not estrogen receptor, thyroid hormone receptor, vitamin D receptor, glucocorticoid receptor, and peroxisome proliferator-activated receptor. Reverse transcription-polymerase chain reaction revealed that HA significantly increased RAR mRNA levels. Furthermore, the mechanism of HA action depends on RAR pathway and up-regulates expression of mRNA for insulin-like growth factor-I, the target gene of RAR. Our findings have now allowed for a refinement in our understanding of TCM with respect to pharmacological regulation of stem cells and may be useful to stem cell biology and therapy.

Research on DC Component Disturbance Suppression Strategy of Islanded T-Type Three-Level Inverter Based on Improved Backstepping Control Theory

He Guo-Feng,Zhou Zi-Chun,Luo Shuang,Li Gou-Jiao 대한전기학회 2024 Journal of Electrical Engineering & Technology Vol.19 No.3

Aiming at the problem that the DC component in the output voltage of the T-type three-level inverter in the island mode is obvious, due to its hardware diferences, a nonlinear control strategy combining the backstepping method, sliding mode theory, and the principle of the second-order generalized integrator (SOGI) is proposed. Firstly, the DC component in the output voltage of the inverter is regarded as a disturbance, and the mathematical model of the inverter with DC component disturbance is established. Secondly, the detected neutral point potential deviation of the DC side of the inverter is compensated to the modulation signal by proportional–integral (PI) control, to maintain the normal operating state of the three-level inverter. Then, the backstepping-sliding mode controller is constructed to improve the robustness T-type three-level inverter. And the SOGI is utilized to overcome the shortcomings of backstepping control which is easy to amplify the measurement noise and cause diferential explosion. Meanwhile, the stability of the designed controller is analyzed by using the Lyapunov stability principle. Finally, the efectiveness of the proposed control strategy is verifed by 10 kW prototype. The experimental results show that the proposed control strategy can not only efectively suppress the DC component of the inverter output voltage and improve the robustness of the system, but also has fast dynamic characteristics.

UHRF2 mRNA Expression is Low in Malignant Glioma but Silencing Inhibits the Growth of U251 Glioma Cells in vitro

Wu, Ting-Feng,Zhang, Wei,Su, Zuo-Peng,Chen, San-Song,Chen, Gui-Lin,Wei, Yong-Xin,Sun, Ting,Xie, Xue-Shun,Li, Bin,Zhou, You-Xin,Du, Zi-Wei Asian Pacific Journal of Cancer Prevention 2012 Asian Pacific journal of cancer prevention Vol.13 No.10

UHRF2 is a member of the ubiquitin plant homeo domain RING finger family, which has been proven to be frequently up-regulated in colorectal cancer cells and play a role as an oncogene in breast cancer cells. However, the role of UHRF2 in glioma cells remains unclear. In this study, we performed real-time quantitative PCR on 32 pathologically confirmed glioma samples (grade I, 4 cases; grade II, 11 cases; grade III, 10 cases; and grade IV, 7 cases; according to the 2007 WHO classification system) and four glioma cell lines (A172, U251, U373, and U87). The expression of UHRF2 mRNA was significantly lower in the grade III and grade IV groups compared with the noncancerous brain tissue group, whereas its expression was high in A172, U251, and U373 glioma cell lines. An in vitro assay was performed to investigate the functions of UHRF2. Using a lentivirus-based RNA interference (RNAi) approach, we down-regulated UHRF2 expression in the U251 glioma cell line. This down-regulation led to the inhibition of cell proliferation, an increase in cell apoptosis, and a change of cell cycle distribution, in which S stage cells decreased and G2/M stage cells increased. Our results suggest that UHRF2 may be closely related to tumorigenesis and the development of gliomas.

Influence of Solution Concentrations on Surface Morphology and Wettability of ZnO Thin Films

Jianguo Lv,Changlong Liu,Feng Wang,Zhitao Zhou,Zhenfa Zi,Yuan Feng,Xiaoshuang Chen,Feng Liu,Gang He,Shiwei Shi,Xueping Song,Zhaoqi Sun 대한금속·재료학회 2013 ELECTRONIC MATERIALS LETTERS Vol.9 No.2

ZnO thin films were grown on silicon substrates using a hydrothermal method. The XRD patterns show that all of the peaks can be attributed to the wurtzite structures of ZnO. The TC value of (002) plane and average crystal size increase first and then decrease with the increase of solution concentration. SEM and AFM results show that many dense hexagonal cylinder particles have been observed on the surface of the thin films, which grown at 0.08 and 0.10 mol/L. The surface roughness of the thin films deposited at 0.06,0.08, 0.10, and 0.12 mol/L are 24.5, 38.3, 32.0, and 39.4 nm, respectively. Surface wettability results show that the preferential orientation along c-axis and surface roughness contribute significantly to the hydrophobicity. The reversible switching between hydrophobicity and hydrophilicity is related to the synergy of the transition of wetting model, surface crystal structure, and surface roughness.

Impact of Cu2O doping on high dielectric properties of CuO ceramics

Dan-Dan Wang,Feng-Zi Zhou,Jing-Xiao Cao,Li-Ben Li,Guo-Ling Li 한국물리학회 2017 Current Applied Physics Vol.17 No.5

Single-phase CuO ceramic samples were prepared with the starting nano powders of CuO þ xCu2O (x ¼ 0, 1, 3, 7% in mole ratio) via solid state reaction method, and characterized by X-ray diffraction, Raman scattering and scanning electron microscopy. For all the samples, the temperature dependences of dielectric constants and losses were measured at the frequencies of 102, 103, 104, 105 and 106 Hz, respectively. With increasing doping content of Cu2O, a strong correlation is demonstrated at given temperature and frequency between the measured dielectric constants and the unit-cell volumes of CuO. The strong correlation is argued in terms of the change in densities of Cu]O defects (e.g. Cu/O vacancies and/or interstitial Cu impurities) due to Cu2O doping, which is supported by the formation energies of Cu]O defects and the corresponding unit-cell volume from first-principles calculations. The high dielectric constant (~103e105) of CuO ceramic is therefore attributed to the reduction in resistance due to Cu/O defects in the grain by Maxwell-Wagner mechanism.

Varistor and dielectric properties of Cr2O3 doped SnO2eZn2SnO4 composite ceramics

Guo-Zhong Zang,Feng-Zi Zhou,Jing-Xiao Cao,Xiao-Fei Wang,Zhao-Wu Wang,Li-Ben Li,Guo-Rong Li 한국물리학회 2014 Current Applied Physics Vol.14 No.12

Cr2O3 doped SnO2eZn2SnO4 composite ceramics were prepared by traditional ceramic processing and the varistor, dielectric properties were investigated. With increasing Cr2O3 content, the breakdown electrical field EB increases from 11 to 92 V/mm and the relative dielectric constant εr measured at 1 kHz, 50 C decreases from 11,028 to 3412, respectively. The barrier height fB about 0.8e0.84 eV and the decreasing of SnO2 grain size suggest that the varistor behavior with high εr is originated from SnO2 eSnO2 or SnO2eZn2SnO4 grain boundary. In the dielectric spectra lower than 1 kHz, a dielectric peak is presented and depressed with increasing bias voltage. Similarly, at high temperature, the dielectric constant also presents a dielectric peak in the temperature spectra and the peak becomes faint with increasing frequency. The exhibition of the dielectric peak is thought to be attributed to the conduction of grain boundary since it is accompanied by the sharp increase of dielectric loss. In addition, a dielectric relaxation with the activation energy about 0.4e0.5 eV was observed in the temperature range of 20 e100 C. Based on the results, the formation mechanism of Schottky barriers at grain boundaries and the varistor behavior with high dielectric constant are well understood.

Involvement of Cdc25c in Cell Cycle Alteration of a Radioresistant Lung Cancer Cell Line Established with Fractionated Ionizing Radiation

Li, Jie,Yang, Chun-Xu,Mei, Zi-Jie,Chen, Jing,Zhang, Shi-Min,Sun, Shao-Xing,Zhou, Fu-Xiang,Zhou, Yun-Feng,Xie, Cong-Hua Asian Pacific Journal of Cancer Prevention 2013 Asian Pacific journal of cancer prevention Vol.14 No.10

Cancer patients often suffer from local tumor recurrence after radiation therapy. Cell cycling, an intricate sequence of events which guarantees high genomic fidelity, has been suggested to affect DNA damage responses and eventual radioresistant characteristics of cancer cells. Here, we established a radioresistant lung cancer cell line, A549R, by exposing the parental A549 cells to repeated ${\gamma}$-ray irradiation with a total dose of 60 Gy. The radiosensitivity of A549 and A549R was confirmed using colony formation assays. We then focused on examination of the cell cycle distribution between A549 and A549R and found that the proportion of cells in the radioresistant S phase increased, whereas that in the radiosensitive G1 phase decreased. When A549 and A549R cells were exposed to 4 Gy irradiation the total differences in cell cycle redistribution suggested that G2-M cell cycle arrest plays a predominant role in mediating radioresistance. In order to further explore the possible mechanisms behind the cell cycle related radioresistance, we examined the expression of Cdc25 proteins which orchestrate cell cycle transitions. The results showed that expression of Cdc25c increased accompanied by the decrease of Cdc25a and we proposed that the quantity of Cdc25c, rather than activated Cdc25c or Cdc25a, determines the radioresistance of cells.