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Febrile seizure, but not hyperthermia alone, induces the expression of heme oxygenase-1 in rat cortex

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Chinese Medical Journal 2006年第3期119卷 191-196页

作者： YANG zhi-xian QIN Jiong DU Jun-bao BU Ding-fang ChanG Xing-zhi han ying Department of Pediatrics First Hospital of Peking UniversityBeijing 100034 China

Background Febrile seizure （FS） is the most common seizure disorders. Approximately one third of children with a febrile seizure have recurrent events. The mechanism of FS remains unclear. Heme oxygenase-1 （HO-1） is a member of the heat shock proteins family and can be induced in the brain by various stresses, including hyperthemia and seizure. This study aimed at investigating the changes of HO-1 in the cortex of rats after recurrent FS. Methods FS in rats was induced ten times, once every 2 days. In a bath of warm water, developing rats were randomly divided into two groups： control group （n=16） and warm water-treated group （n=50）. The latter group was subdivided into hyperthermia group （n=19） and FS group （n=23）. The expression and content of HO-1 mRNA in cortex were observed using in situ hybridization and quantitative reverse transcription-polymerase chain reaction （RT-PCR）. The content of HO- 1 protein in cortex was measured using Western blotting. Results HO-1 mRNA expression of cortex neurons in FS group was markedly increased in comparison with those in hyperthermia and control groups （P=0.00）, however, there was no statistic difference bftween hyperthermia group and control group （P=0.16）. The relative amount of HO- 1 mRNA in cortex in FS group was increased by 53.13% and 96% in comparison with those in hyperthermia group and control group respectively （P=0.00）, but there was no obvious difference between the later two groups （P=0.051）. Western blotting analysis showed that the HO-1 protein content in cortex in FS group was increased by 198% and 246% in comparison with those in hyperthermia group and control group respectively （P=0.00）. There was no obvious difference in HO-1 protein content between the later two groups （P=0.09）. Conclusions Recurrent FS in rats can cause the increase of HO-1 mRNA and protein in cortex which may be involved in the mechanism of FS. The short-time recurrent hyperthermia can not induce the increase of HO-1 mRNA and prot

关键词： febrile seizure heme oxygenase cortex

Effect of surface free energy of acetylene black powder on air electrode performance

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Rare Metals 2006年第z1期25卷 364-368页

作者： OU Xiuqin LIU Shuguang LIANG Guangchuan LI ying zhi Xiaoke han Bin Institute of Power and Ecomaterial Science Hebei University of TechnologyTianjin 300130China

The effects of acetylene black powder surface free energy on air electrode electrochemical performance and lifetime were *** acetylene black was immersed in 30%H_(2)O_(2)at room temperature and the changes of functional groups and surface free energy were investigated by X-ray Photoelectron Spectroscopy(XPS)and powder contact angle(CA).The air electrode performance was characterized by the potential polarization curves and the lifetime was measured by constant-current *** shows that,its surface free energy is the lowest when the acetylene black is immersed in H_(2)O_(2)for 240 *** polarization potential of the air electrode prepared by the pretreated acetylene black is 0.25 V(***/HgO),0.21 V lower than the air electrode with untreated acetylene black when the working current density is 100 mA·cm^(-1).And its lifetime is over 800 h at 80 mA·cm^(-1).The pretreatment of acetylene black for proper time by H_(2)O_(2)is favorable for the stability of the tri-phase reaction interface of air electrode and improvement of its performance.

关键词： air electrode acetylene black immerse surface free energy electrochemical performance

Transcriptome-based analysis of key signaling pathways affecting the formation of primordial germ cell in chickens

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Journal of Integrative Agriculture 2024年第5期23卷 1644-1657页

作者： ying Ding Qiong zhi Qisheng Zuo Kai Jin Wei han Bichun Li Key Laboratory of Animal Genetics Breeding and Molecular Design of Jiangsu ProvinceCollege of Animal Science and TechnologyYangzhou UniversityYangzhou 225009China Joint International Research Laboratory of Agriculture and Agri-Product Safety of the Ministry of Education of China Yangzhou UniversityYangzhou225009China Poultry Research Institute Chinese Academy of Agricultural Sciences/Jiangsu Institute of Poultry ScienceYangzhou 225009China

Bone morphogenetic protein 4(BMP4)can induce the formation of chicken primordial germ cells(PGCs)in vitro;however,its regulatory mechanism in poultry remains *** study aimed to use RNA-seq to analyze PGCs in chicken embryos and iPGCs induced by BMP4 in vitro,clarify the internal regulatory factors of PGCs,analyze the mechanism of the formation of PGCs,and lay a theoretical foundation for the further optimization of PGCs induction *** stem cells(ESCs),PGCs and iPGCs induced by BMP4 in vitro were *** transcriptional maps of the three cell types were studied using *** results showed 6,142 genes differentially expressed between PGCs and iPGCs,of which 2,728 were upregulated in iPGCs and 3,414 were downregulated in *** to that in ESCs,BMP4 was significantly upregulated in PGCs and *** results showed that both the TGF-βand Wnt signaling pathways were activated during the formation of PGCs in vitro and in vivo,and the activation was more significant during iPGCs induced by *** expression of Nodal,an inhibitory factor of TGF-βsignaling,was significantly decreased in PGCs and iPGCs,but was not expressed in iPGCs,which further supports our ***,the Lysosome and PI3K-AKT signaling pathways were significantly enriched in PGCs and iPGCs,***,transmission electron microscopy(TEM)results showed that the number of autolysosomes was significantly higher after the addition of BMP4,which is consistent with the KEGG ***,the number of PGCs was significantly reduced after ATG14 was interfered in vivo and in *** conclusion,this study screened out the key signaling pathways during the formation of PGCs,aiming to provide help for enriching the mechanism network regulating PGCs formation in chicken and laying a theoretical foundation for further improving the efficiency of inducing PGCs in vitro.

关键词： RNA-seq BMP4 PGCs ATG14 chicken

Mixed Dead-time Effect Suppression Strategy for Modular Multilevel Converters

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CSEE Journal of Power and Energy Systems 2024年第3期10卷 1075-1084页

作者： zhi Geng Minxiao han School of Electrical and Electronic Engineering North China Electric Power UniversityBeijing 102206China IEEE

Dead time is necessary for the coupled power switches to prevent shoot-through,especially in the modular multilevel converters(MMCs)with a large number of power *** paper proposes a dead-time effect suppression strategy for MMCs with nearest level *** operational principles of MMCs are first *** to the operational features of MMCs,the method that removes a switching signal from the coupled switches and the reduced switching frequency voltage balancing algorithms(RSFVBAs)are mixed in the proposed *** the intervals that are furthest away from the zerocrossing points(ZCP)of arm currents,the single switching signal method can completely eliminate the dead-time effect(DTE).Alternatively,the DTE is suppressed by the RSFVBA in intervals that are close to the *** the combination of the two methods,the dependence of the DTE suppression method on currents is reduced and the influences of ZCP are also released without degrading the normal operation performance of ***,the output performance of MMCs is improved and the voltage stress on the arm inductor dramatically ***,the validation of the method is verified by the simulation results with the professional tool Matlab/Simulink.

关键词： Dead-time effect modular multilevel converters switching frequency voltage balancing algorithm

SUCCESSFUL EXTRACORPOREAL MEMBRANE OXYGENATION SUPPORT IN A PATIENT WITH FULMINANT MYOCARDITIS

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Chinese Medical Sciences Journal 2006年第3期21卷 194-196页

作者： Yong Yuan Jian-ting Dong Xuan-sheng Huang Li-ting Zhang Bin-fei Li zhi-gang Zhang ying han Heart Center Zhongshan People＇s Hospital Zhongshan 528403

FULMINANT myocarditis complicated with refractory cardiogenic shock carries a very high mortality （76%）. Herein we report our experi-ence in treating a 23-year-old Chinese woman with fulminant myocarditis complicate... 详细信息

关键词： extracorporeal membrane oxygenation fulminant myocarditis treatment

Currentless Multiple Switch Open-Circuit Faults Diagnosis for Modular Multilevel Converters with Nearest Level Modulation in HVDC Systems

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CSEE Journal of Power and Energy Systems 2024年第4期10卷 1642-1653页

作者： zhi Geng Minxiao han Changjiang Xia Longze Kou School of Electrical and Electronic Engineering North China Electric Power University(NCEPU)Beijing 102206China State Key Laboratory of Advanced Power Transmission Technology Global Energy Interconnection Research InstituteBeijing 102209China

Due to the large number of submodules(SMs),and modular multilevel converters(MMCs)in high-voltage applications,they are usually regulated by the nearest level modulation(NLM).Moreover,the large number of SMs causes a challenge for the fault diagnosis strategy(FDS).This paper proposes a currentless FDS for MMC with *** FDS,the voltage sensor is relocated to measure the output voltage of the *** acquire the capacitor voltage and avoid increasing extra sensors,a capacitor voltage calculation method is *** on the measurement of output voltages,the faults can be detected and the number of different-type switch open-circuit faults can be confirmed from the numerous SMs in an arm,which narrows the scope of fault ***,the faulty SMs and faulty switches in these SMs are further located without arm current according to the sorting of capacitor voltages in the voltage balancing *** FDS is independent of the arm current,which can reduce the communication cost in the hierarchical control system of ***,the proposed FDS not only simplifies the identification of switch open-circuit faults by confirming the scope of faults,but also detects and locates multiple different-type faults in an *** effectiveness of the proposed strategy is verified by the simulation results.

关键词： Fault diagnosis high voltage direct current(HVDC) modular multilevel converter(MMC) nearest level modulation(NLM) switch open-circuit fault

An axisymmetric characteristic model for enhancing prediction of centrifugal compressor characteristics

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Chinese Journal of Aeronautics 2024年第4期37卷 203-215页

作者： Peng REN Xiangjun FANG Zeyu JIAO ying han School of Energy and Power Engineering Beihang UniversityBeijing 100191China Guangdong Key Laboratory of Modern Control Technology Institute of Intelligent ManufacturingGuangdong Academy of SciencesGuangzhou 510070China

Rapid and accurate determination of compressor characteristic maps is essential for the initial design of centrifugal compressors in aircraft power systems. The accuracy of existing methodologies, which rely on combinations of loss models, varies significantly depending on the compressor's geometry and operational range. This variance necessitates substantial experimental or Computational Fluid Dynamics(CFD) data for coefficient calibration. To address this challenge, this study presents an axisymmetric characteristic model for compressor performance assessment. This model incorporates the factors of blade angle, meridional passage area, and the radial deflection angle of meridional streamlines of the compressor. These factors are derived from fundamental aerodynamic equations encompassing mass, momentum, and energy conservation of the compressor. In contrast to conventional one-dimensional approaches, the proposed method reduces the number of loss coefficients and more effectively accounts for the impact of geometric alterations on centrifugal compressor properties. Furthermore, the model reduces dependence on experimental and CFD data. Efficacy of the model is validated using experimental data from four distinct types of centrifugal compressors. Correlation analysis reveals that the model's coefficients can be expressed as functions of the ratio of the Reynolds number to the impeller tip speed. This ratio serves as a characteristic parameter for the design and optimization of centrifugal compressors. Consequently, the proposed method offers an efficient and accurate means for the quick computation of centrifugal compressor characteristics. This is of great significance for improving the efficiency of centrifugal compressors and reducing energy consumption.

关键词： Centrifugal compressor Positive problem Characteristic prediction Aerodynamic characteristic Axisymmetric model

Struvite Recovery from Swine Waste Biogas Digester Effluent through a Stainless Steel Device under Constant pH Conditions

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Biomedical and Environmental Sciences 2009年第3期22卷 201-209页

作者： P.W.ANTON PERERA College of Environmental and Resource Sciences Zhejiang University

Objective To investigate the struvite precipitation under constant and non-constant pH conditions and to test a stainless steel device under different operating regimes to maximize the recovery of struvite. Methods The molar ratio of NH4^＋： Mg^2＋ PO43 was adjusted to 1： 1.2：1.2 and pH was elevated to 9.0. The absorbance measurement was used to trace the process of struvite crystallization. Wastewater and precipitate analysis was done by standard analytical methods. Results The pH constant experiment reported a significantly higher struvite precipitation （24.6±0.86 g） than the non-constant pH experiment （19.8±1.86 g）. The SAR ranged from 5.6 to 8.2 g m^-2h^-1 to 3.6-4.8 g m^-2h^-1 in pH constant and non-constant experiments, respectively. The highest struvite deposit on the device was found in regime 3 followed by in regimes 2 and 4. The highest PO4^3- （97.2%） and NH4^＋（71%） removal was reported in the R1 regime. None of the influent Cu^2＋ or Zn^2＋ was precipitated on the device. Conclusion A higher struvite yield is evident in pH constant experiments. Moreover, the stainless steel device facilitates the isolation of heavy metal free pure （around 96%） struvite from swine waste biogas digester effluent contaminated with Cu^2＋ and Zn^2＋ and the highest yield is attainable with the device operating at 50 rpm with agitation by a magnetic stirrer.

关键词： Struvite recovery Accumulation device Swine waste Constant pH Struvite precipitation

An unexpected approach to enhance specific surface area and mesopore amount of polyaniline by Zn doping

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Rare Metals 2024年第9期43卷 4585-4594页

作者： zhi-Da Zhu Yu-Zhe han Xiao-Bi Jing School of Mechanical Engineering Yangzhou University School of Chemistry and Chemical Engineering Yangzhou University

Poly-p-anisidine could be easily fabricated via the oxidative polymerization reaction of p-anisidine using H2O2as the green oxidant. It was unexpectedly found that zinc doping could significantly improve the adsorption ability of the material versus heavy metals such as Pb, Cu,Pd, Ag and Hg. Results of nitrogen adsorption–desorption experiments demonstrated that Zn doping could enhance the specific surface area and mesopore amount of the prepared material, which might facilitate its absorption to metals. This work not only provides a novel material for the treatment of heavy metal-polluted water but also leads to a nice mesoporous catalyst support for environment protection and organic synthesis, i.e. the Zn-doped poly-panisidine can be employed as the catalyst support to prepare Cu@PANI-OMe/Zn or Pd@PANI-OMe/Zn for the oxidative degradation reaction of phenol or Suzuki–Miyaura coupling reactions, respectively. It discloses a new strategy for fabricating the mesoporous polyaniline materials with profound application potential.

关键词： Adsorption Catalysis Porous materials Rare metal concentration Surfaces