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Biomedical and Environmental Sciences 2007年第5期20卷 386-391页

作者： JIANG YUE peng WANG YING-HUI LIU JUN-YU WU JIE CHEN ren-xiu peng Department of Pharmacology College of Basic Medicine Wuhan University Wuhan 430071 Hubei China Inspection ＆ Quarantine Technical Center Hubei Entry-exit Inspection and Quarantine Bureau Wuhan 430022 Hubei China

Objective To establish a fast and sensitive method for the detection of 8-hydroxy-2’-deoxyguanosine （8-OHdG） in precision-cut rat liver slices by HPLC-MS/MS and to investigate isoniazid （INH） -induced oxidative DNA damage. Methods Precision-cut liver slices （300 μm） were prepared from male rats, and incubated with INH （0.018 mol/L） for 2 h after 1 h preincubation. DNA in the slices was extracted and digested into free nucleosides at 37℃ . The samples were injected into HPLC-MS/MS after the proteins were removed. The level of oxidative DNA damage was estimated using the ratio of 8-OHdG to deoxyguanosine （dG）. Results The limit of detection of 8-OHdG was 1 ng/mL （S/N=3） and the intra-assay relative standard variation was 3.38% when one transition 284.3/168.4 was used as a quantifier and another two transitions 284.3/140.2, 306.1/190.2 as qualifiers. 8-OHdG and dG were well separated, as indicated by elution at 10.02 and 7.37 min, respectively. INH significantly increased the ratio of 8-OHdG to dG in rat liver slices （P〈0.05）. Conclusion 8-OHdG in precision-cut liver slices could be sensitively determined by HPLC-MS/MS. HPLC-MS/MS coupled with precision-cut tissue slices is a fast and reliable analytical technique to evaluate oxidative DNA damage of target tissues caused by procarcinogens and cytotoxins.

关键词： Isoniazid 8-Hydroxy-2'-deoxyguanosine HPLC-MS/MS Precision-cut liver slices

CYP2E1 mediated isoniazid-induced hepatotoxicity in rats

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Acta Pharmacologica Sinica 2004年第5期25卷 157-162页

作者： Jiang YUE, ren-xiu peng1, Jing YANG, Rui KONG, Juan LIUDepartment of Pharmacology, Medical College of Wuhan University, Wuhan 430071, China Department of Pharmacology Medical College of Wuhan University Wuhan 430071

AIM: To investigate the role of CYP2E1 in isoniazid (INH)-induced hepatotoxicity and the influence of rifampicin(RFP) on INH-induced liver injury. METHODS: Rats were treated with INH alone (100 mg/kg, ip) or co-administeredwith RFP (100 mg/kg, ig) for 10 d and 21 d. Hepatotoxicity was assayed by plasma enzymes (sALT, sAST) andhistopathological examinations. Hepatic CYP2E1 activity was measured by aniline hydroxylase (ANH), and CYP2E1mRNA expression was determined by RT-PCR. Plasma hydrazine concentration was determined by ***: For a 10 d INH-treatment, hepatic CYP2E1 level was increased to 3.7-fold over the control; liverimpairment appeared after 21 d treatment, while CYP2E1 and plasma hydrazine were, respectively, increased to 4.6-fold and 1.7-fold. However, in INH-RFP group for 10 d, CYP2E1 and plasma hydrazine were, respectively,decreased by 13 % and 18 % over INH group; similarly, hepatic injury is equal to INH group appeared after 21 d,and CYP2E1 was further decreased by 26 %. Correlation analysis showed that sALT had a positive correlation withplasma hydrazine and with CYP2E1 activity; CYP2E1 activity was also markedly correlated with plasma *** compared with control, there is no difference in changes of CYP2E1 mRNA expression in INH and INH-RFPtreatment for 21 d. CONCLUSION: The metabolite of INH, hydrazine, plays an important role in INH-inducedhepatotoxicity in rats. The induction of CYP2E1 by hydrazine is involved in the hepatotoxicity of INH. RFP doesnot exacerbate INH-induced hepatotoxicity in short term, which relates to down-regulation of CYP2E1.

关键词： isoniazid rifampin hydrazines cytochrome P-450 CYP2E1

A Weighted Flow related to a Trudinger–Moser Functional on Closed Riemann Surface

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Acta Mathematica Sinica,English Series 2024年第9期40卷 2244-2262页

作者： peng xiu YU School of Mathematics Renmin University of ChinaBeijing 100872P.R.China

In this paper,with(Σ,g)being a closed Riemann surface,we analyze the possible concentration behavior of a heat flow related to the Trudinger–Moser *** obtain a long time existence for the *** along some sequence of times t_(k)→+∞,we can deduce the convergence of the flow in H2(Σ).Furthermore,the limit function is a critical point of the Trudinger–Moser functional under certain constraint.

关键词： Trudinger-Moser inequality global convergence heat flow

Influences of 3-methylcholanthrene,phenobarbital and dexamethasone on xenobiotic metabolizing-related cytochrome P450 enzymes and steroidogenesis in human fetal adrenal cortical cells

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Acta Pharmacologica Sinica 2006年第8期27卷 1093-1096页

作者： Hui WANG~2 Min HUANG ren-xiu peng Jiang LE Department of Pharmacology,Basic Medical School of Wuhan University,Wuhan 430071,China DepartmentofPharmacologyBasicMedicalSchoolofWuhanUniversity Wuhan430071China

Aim:To explore the influence and possible mechanism of xenobiotics on adrenalsteroidogenesis during fetal ***:Primary human fetal adrenalcortical cells were prepared,cultured and treated with 3-methylcholanthrene,phe-nobarbital and *** activities of 7-ethoxyresorufin O-dealkylase,benzphetamine,aminopyrine and erythromycin N-demethylases were measuredby enzyme *** the same time,quantitative analysis of steroid hormonescortisol,aldosterone,testosterone and progesterone were carried out in culturalmedium by ***:The activities of benzphetamine andaminopyrine N-demethylase were increased in the cultural fetal adrenal cells treatedwith phenobarbital(0.25-1 mmol/L)for ***(25-100 μmol/L)alsoincreased the activity of erythromycin *** activity of 7-ethoxyresorufin O-dealkylase was undetected in the cells treated without andwith 3-methylcholanthrene(0.5-2μmol/L).Meanwhile,the contents of mediumcortisol,aldosterone and progesterone were decreased after treatment with ***,aldosterone and progesterone concentrations werealso slightly decreased with *** enhanced the pro-ductions of cortisol and progesterone *** trend of testosteroneconcentration was uncertain after 3-methylcholanthrene,phenobarbital or dexam-ethasone ***:3-Methylcholanthrene,phenobarbital or dex-amethasone could interfere with the synthesis of cortisol,aldosterone and proges-terone in primary human fetal adrenal cortical cells,which likely act throughxenobiotic metabolizing-related cytochrome P450 isoform activation.

关键词： xenobiotics steroidogenesis adrenal glands cytochrome P-450 enzyme system fetal development

Supercoiled DNA Minicircles under Double-strand Breaks

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Chinese Journal of Polymer Science 2024年第9期42卷 1353-1359,I0007页

作者： Ye-peng Qiao Chun-Lai ren National Laboratory of Solid State Microstructures and Department of Physics Collaborative Innovation Center of Advanced MicrostructuresNanjing UniversityNanjing210093China

Understanding how supercoiled DNA releases intramolecular stress is essential for its functional ***,the molecular mechanism underlying the relaxation process remains insufficiently *** we employed MD simulations based on the oxDNA2 model to investigate the relaxation process of a 336-base pair supercoiled minicircular DNA under double-strand breaks with two fixed *** simulations show that the conformational changes in the DNA occur continuously,with intramolecular stress release happening abruptly only when the DNA chain traverses the breakage *** relaxation process is influenced not only by the separation distance between the fixed ends but also their ***,we observe an inhibitory effect on the relaxation characterized by small angles,where short terminal loops impede DNA conformational adjustments,preserving the supercoiled *** findings elucidate the intricate interplay between DNA conformational change,DNA motion and intramolecular stress release,shedding light on the mechanisms governing the relaxation of supercoiled DNA at the molecular level.

关键词： Supercoiled DNA DNA minicircle DNA relaxation oxDNA model MD simulation

Probability modeling for robustness of multivariate LQG designing based on ship lateral motion

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Journal of Marine Science and Application 2005年第4期4卷 18-22页

作者： ZHAO Xi-ren peng xiu-yan YIN Zhong-feng School of Automation Harbin Engineering University Harbin 150001 China

The robustness of LQG designing for latitudinal movement of ship is mainly discussed, when its hydrodynamic parameters fluctuate around criterion value at random on the proportional distributing. When a given ship state at the speed of 18 kn and the course of 45° under Rank 5 state of sea, and the hydrodynamic parameters of the ship fluctuate at random on the proportional distributing with a range of ± 10% , ± 20% , ± 30% , the robustness of muhivariate LQG designing for ship is analyzed with applying the probability modeling of relative controlling effect, The result of simulating shows that when the hydrodynamic parameters of ship fluctuates the relative controlling effect of the LQG designing submit to normal distribution and the mean value of relative controlling effect has no remarkable changes comparing to that without perturbation of hydrodynamic parameter,

关键词： hydrodynamic parameters perturbation LQG designing statislic modeling

The Sequential Pricing of Ride-Hailing System with rental Service in the Context of Fleet Electrification

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Journal of Systems Science and Systems Engineering 2024年第1期33卷 77-105页

作者： Yaoyao Ku peng Wu Qiang ren Yiqing Wang Business School Sichuan UniversityChengdu610065China

Surging demand and reduced capacity in the ride-hailing industry have prompted numerous ride-hailing platforms to build their own car-rental services catering to drivers who do not possess private vehicles. However, the trade-off between the ride-hailing service and the car-rental service is an important issue that is still unclear in theory. Moreover, ride-hailing platforms are transitioning towards all-electric fleets in the context of Carbon Neutrality goals and government regulations. This paper considers a ride-hailing system comprising a monopolist ride-hailing platform, an electric vehicle (EV) rental firm, and a gasoline vehicle (GV) rental firm. Furthermore, we build a stylized model to study the sequential pricing of the system. The equilibrium outcomes show the significant impact of the ride-hailing platform’s decision to continue or withdraw offering EV rental services on EV and GV drivers’ net earnings, rental prices, and wages. The ride-hailing platform providing EV rental services increases EV drivers’ net earnings but decreases the GV driver wages and rental prices. However, the EV rental service offered by the ride-hailing platform does not necessarily lead to an increased total profit for the system. The improved profitability of the system by the ride-hailing platform providing EV rental services is contingent upon lower rider prices and higher fuel costs. The ride-hailing platform’s EV rental services provision also effectively fosters the ride-hailing fleet’s electrification. Furthermore, as the number of riders increases, the ride-hailing platform should reduce the commission rate for EV drivers to maintain competitiveness and profitability.

关键词： Ride-hailing system car rental fleet electrification sequential pricing differential wage scheme

Characterization and identification towards dynamic-based electrical modeling of lithium-ion batteries

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Journal of Energy Chemistry 2024年第5期92卷 738-758页

作者： Chuanxin Fan Kailong Liu Yaxing ren Qiao peng School of Automation Nanjing Institute of TechnologyNanjing 211167JiangsuChina School of Control Science and Engineering Shandong UniversityJinan 250100ShandongChina School of Engineering University of LincolnLincoln LN67TSUK Information Technology Analytics&Operations GroupQueen’s University BelfastBelfast BT95EEUK

Lithium-ion batteries are widely recognized as a crucial enabling technology for the advancement of electric vehicles and energy storage systems in the *** design of battery state estimation and control algorithms in battery management systems is usually based on battery models,which interpret crucial battery dynamics through the utilization of mathematical ***,the investigation of battery dynamics with the purpose of battery system identification has garnered considerable attention in the realm of battery *** methods in terms of linear and nonlinear response of lithium-ion batteries have emerged as a prominent area of study in this *** review has undertaken an analysis and discussion of characterization methods,with a particular focus on the motivation of battery system ***,this work encompasses the incorporation of frequency domain nonlinear characterization methods and dynamics-based battery electrical *** aim of this study is to establish a connection between the characterization and identification of battery systems for researchers and engineers specialized in the field of batteries,with the intention of promoting the advancement of efficient battery technology for real-world applications.

关键词： Lithium-ion battery Battery dynamics Nonlinear characterization Nonlinear battery model

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

On the superconvergence of a WG method for the elliptic problem with variable coefficients

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Science China Mathematics 2024年第8期67卷 1899-1910页

作者： Junping Wang Xiaoshen Wang xiu Ye Shangyou Zhang peng Zhu Division of Mathematical Sciences National Science FoundationAlexandriaVA 22314USA Department of Mathematics University of Arkansas at Little RockLittle RockAR 72204USA Department of Mathematical Sciences University of DelawareNewarkDE 19716USA College of Data Science Jiaxing UniversityJiaxing 314001China

This article extends a recently developed superconvergence result for weak Galerkin(WG)approximations for modeling partial differential equations from constant coefficients to variable *** superconvergence features a rate that is two orders higher than the optimal-order error estimates in the usual energy and L^(2)*** extension from constant to variable coefficients for the modeling equations is highly *** underlying technical analysis is based on a sequence of projections and *** results confirm the superconvergence theory for second-order elliptic problems with variable coefficients.

关键词： weak Galerkin finite element methods superconvergence second-order elliptic problems stabilizerfree