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Optimization of axial symmetrical FGM under the transient-state temperate field

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International Journal of Minerals,Metallurgy and Materials 2012年第1期19卷 59-63页

作者： xiao-dan Zhang Ya-li Hong Ai-hua Li School of Mathematics and Physics University of Science and Technology Beijing Beijing 100083 China Department of Mathematical Science Montclair State University New Jersey 07043 USA

A numerical procedure for analyzing the temperature distribution in a hollow axisymmetric cylinder, made of functionally gradient material （FGM）, was investigated. Based on the thermal elasticity theory and the arbitrary difference precise integration （ADPI） method, temperature distribution through the FGM cylinder in the ring section under a transient-state temperature field was developed and presented. A genetic algorithm （GA） was applied to the thermal stress optimal design of an FGM hollow cylinder, and as a result, the minimum thermal stress distribution in the FGM cylinder was obtained. A corresponding numerical procedure regarding to a ceramic-metal FGM cylinder was perforrned. and the comnutational results were discussed.

关键词： functionally gradient materials axial symmetry tempemtttre distribution genetic algorithms numerical methods

Genetic variability in adapter proteins with APPL1/2 is associated with the risk of coronary artery disease in type 2 diabetes mellitus in Chinese Han population

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Chinese Medical Journal 2011年第22期124卷 3618-3621页

作者： MA xiao-wei DING Shan MA xiao-dan GU Nan GUO xiao-hui Department of Endocrinology Peking University First Hospital Beijing 100034 China

Background Adaptor proteins containing PH domain, PTB domain, and leucine zipper motif 1 and 2 （APPL1/2） play a key role in cell proliferation in many tissues. APPL1 or APPL2 as an adaptor for adiponectin receptors mediates the signaling pathway of adiponectin which acts as an anti-atherosclerotic adipokine. This study aimed to investigate whether genetic variations in the APPL 1/2 genes affect the risk of coronary artery disease （CAD） in Chinese patients with type 2 diabetes mellitus （T2DM）. Methods Seven haplotype-tagging single nucleotide polymorphisms （tag-SNPs） were selected from CHB HapMap database （Phase II） and total 203 CAD-positive cases and 106 CAD-negative controls with T2DM were genotyped for the 7 tag-SNPs by polymerase chain reaction-restriction fragment length polymorphism （PCR-RFLP） assay. Results The minor allele G of rs4640525 at APPL1 locus was protective from CAD in patients with T2DM, with the carriers of genotype CC at higher risk of CAD compared with non-carriers （OR=2.830, 95% Cl 1.285-6.230, P=0.010; OR＇=4.992, 95% C1=1.758-14.173, P＇0.003, after adjustment for the other known CAD risk factors）; the homozygotes of AA at rs11112412 in APPL2 gene had higher risk of CAD compared with those of GG （adjusted OFt=5.697, 95% Cl 1.006-32.257, P=0.049）. Conclusion Genetic variation（s） in APPL 1/2 may be associated with CAD risk in T2DM in Chinese population.

关键词： APPL1 APPL2 genes coronary artery disease, type 2 diabetes mellitus Chinese

Global patterns in above-ground net primary production and precipitation-use efficiency in grasslands

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Journal of Mountain Science 2018年第8期15卷 1682-1692页

作者： QIN xiao-jing HONG Jiang-tao MA Xing-xing WANG xiao-dan Key Laboratory of Mountain Surface Processes and Ecological Regulation Institute of Mountain Hazards and EnvironmentChinese Academy of ScienceChengdu 610041China University of Chinese Academy of Sciences Beijing 100049China College of Urban and Environment Sciences Shanxi Normal UniversityLinfen 041000China

The above-ground net primary production(ANPP) and the precipitation-use efficiency(PUE) regulate the carbon and water cycles in grassland ecosystems, but the relationships among the ANPP, PUE and precipitation are still controversial. We selected 717 grassland sites with ANPP and mean annual precipitation(MAP) data from 40 publications to characterize the relationships ANPP–MAP and PUE–MAP across different grassland types. The MAP and ANPP showed large variations across all grassland types, ranging from 69 to 2335 mm and 4.3 to 1706 g m^(-2), respectively. The global maximum PUE ranged from 0.19 to 1.49 g m^(-2) mm^(-1) with a unimodal pattern. Analysis using the sigmoid function explained the ANPP–MAP relationship best at the global scale. The gradient of the ANPP–MAP graph was small for arid and semi-arid sites(MAP <400 mm). This study improves our understanding of the relationship between ANPP and MAP across dry grassland ecosystems. It provides new perspectives on the prediction and modeling of variations in the ANPP for different grassland types along precipitation gradients.

关键词： Litter decomposition Alpine communities Tea bag index Carbon cycle Above-ground net primary production Precipitation-use efficiency Sigmoid function Precipitation gradients

Short-term effects of yak and Tibetan sheep urine deposition on soil carbon and nitrogen concentrations in an alpine steppe of the northern Tibetan Plateau, China

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Journal of Mountain Science 2022年第4期19卷 1156-1167页

作者： DU Zi-yin WANG xiao-dan CAI Yan-jiang School of Geographical Sciences China West Normal UniversityNanchong 637009China Xainza Alpine Steppe and Wetland Ecosystem Observation Station Institute of Mountain Hazards and EnvironmentChinese Academy of Sciences&Ministry of Water ResourcesChengdu 610041China College of Environmental and Resource Sciences Zhejiang A&F UniversityHangzhou 311300China

Yak(Bos grunniens) and Tibetan sheep urine deposited onto the alpine grasslands of the Qinghai-Tibetan Plateau is an important pathway for nutrient return, and it is closely related to soil fertility and alpine grassland productivity. However, hitherto, few studies have reported the effects of yak and Tibetan sheep urine deposition on soil carbon(C) and nitrogen(N) concentrations and the possible functional mechanisms under field conditions in alpine grasslands. To explore the status of soil C and N responding to the immediate N addition from livestock urine, we conducted a 28-d field experiment with three treatments, which include the application of yak urine(YU) and Tibetan sheep urine(TSU) application, and the control(CK, no application of urine). The results showed that YU treatment increased the soil moisture content and p H at 0-10 cm across the 28-day experimental period. Urine application resulted in the fluctuation of soil organic C(SOC) and increased topsoil SOC concentration during the middle and later periods of the experiment. Application of YU evidently increased the soil total N(TN) concentration in the 0-10 cm layer, while it did not affect the SOC concentrations in the 10-20 and 20-30 cm layers. Compared with the control, YU treatment significantly(P<0.05) increased the 0-10 and 10-20 cm soil ammonium-N(NH;-N) concentration throughout the 28 days, while the TSU treatment significantly(P<0.05) increased the 0-10 and 10-20 cm soil nitrate-N(NO;-N) concentration. Urine N input changed soil physicochemical properties, nitrification, denitrification, and N leaching processes, and therefore affected the availability of N accumulation and consumption in soil. Under these conditions, the trade-off between soil NH;-N and NO;-N under the influence of yak and Tibetan sheep urine application would change the form and concentration of available N, thereby altering the plant N uptake and utilization strategy of alpine grassland. The conclusions of this study coul

关键词： Livestock urine Mineral nitrogen Nitrification Denitrification Qinghai-Tibetan Plateau

On the ordering of the Kirchhoff indices of the complements of trees and unicyclic graphs

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Applied Mathematics(A Journal of Chinese Universities) 2020年第3期35卷 308-320页

作者： CHEN xiao-dan HAO Guo-liang JIN De-quan College of Mathematics and Information Science Guangxi UniversityNanning 530004China Guangxi Center for Mathematical Research Guangxi UniversityNanning 530004China College of Science East China University of TechnologyNanchang 330013China

The Kirchhoff index Kf(G) of a graph G is defined to be the sum of the resistance distances between all pairs of vertices of G. In this paper, we develop a novel method for ordering the Kirchhoff indices of the complements of trees and unicyclic graphs. With this method, we determine the first five maximum values of Kf■ and the first four maximum values of Kf(ū),where ■ and ū are the complements of a tree T and unicyclic graph U, respectively.

关键词： Kirchhoff index tree unicyclic graph complement ordering

2020-2023年辽宁省小肠结肠炎耶尔森菌表型分布和分子特征研究

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中国人兽共患病学报 2024年第2期40卷 97-103页

作者：李雪孙婷婷魏彤竹王晓丹刁文丽辽宁省疾病预防控制中心沈阳110005

目的通过研究表型分布和分子特征的关联性,了解辽宁省小肠结肠炎耶尔森菌(Yersinia enterocolitica,YE)的流行趋势,为辽宁省YE病的监测和防控提供数据支撑。方法对2020-2023年辽宁省60株YE分离株进行血清分型、生物分型、毒力基因检测和... 详细信息

目的通过研究表型分布和分子特征的关联性,了解辽宁省小肠结肠炎耶尔森菌(Yersinia enterocolitica,YE)的流行趋势,为辽宁省YE病的监测和防控提供数据支撑。方法对2020-2023年辽宁省60株YE分离株进行血清分型、生物分型、毒力基因检测和PFGE、MLST分子分型研究。结果60株YE分离株可分为4个血清型、2个生物型、8个毒力基因型和29种ST型。2023年40株YE分离株分为8组PFGE优势带型A-G,A组为2023年沈阳市地区流行分子型。PFGE的分辨力(DI)为0.954,MLST分辨力(DI)为0.948。ST3、ST252位于树状图核心位置向四周发散。PFGE较MLST方法分辨力稍高。结论2020-2023年辽宁省YE分离株流行致病血清型是O∶3,毒力基因型和ST型均呈现多样化状态。沈阳市YE污染较严重。应重点加强对于生物1A型菌株的研究工作。猪是辽宁省地区重要的宿主和传染源。PFGE和MLST对YE分离株分型均是可行的,ST分型与PFGE分型具有一致性。

关键词：小肠结肠炎耶尔森菌血清型生物型基因型分子型

AA-CYP-HETE/EETs代谢通路与心血管疾病治疗药物研究现状的分析

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中国临床药理学杂志 2024年第4期40卷 619-623页

作者：胡明霞何永芸姚玥莫晓丹杨秀芬广西中医药大学药学院广西壮族自治区南宁530200 广西中医药大学广西壮瑶药重点实验室广西壮族自治区南宁530200 广西中医药大学广西高校中药神经-代谢及免疫药理重点实验室广西壮族自治区南宁530200

20-羟基二十碳四烯酸(20-HETE)及环氧二十碳三烯酸(EETs)是花生四烯酸(AA)经细胞色素P450(CYP)酶系代谢的产物。20-HETE主要由CYP4A、CYP4F将AA代谢产生,对心脑血管系统有一定的毒性作用。EETs主要由CYP2J、CYP2C将AA代谢产生,对心脑血... 详细信息

20-羟基二十碳四烯酸(20-HETE)及环氧二十碳三烯酸(EETs)是花生四烯酸(AA)经细胞色素P450(CYP)酶系代谢的产物。20-HETE主要由CYP4A、CYP4F将AA代谢产生,对心脑血管系统有一定的毒性作用。EETs主要由CYP2J、CYP2C将AA代谢产生,对心脑血管系统有一定的保护作用。本文通过查阅文献综述AA-CYP-HETE/EETs代谢通路相关药物对心肌肥厚、高血压、心力衰竭、心肌梗死等心血管疾病的作用及作用机制,以期为心血管疾病的临床用药提供参考,为心血管疾病治疗药物的研究和开发提供思路与方向。

关键词：花生四烯酸细胞色素P450 20-羟基二十碳四烯酸环氧二十碳三烯酸心血管疾病

Application of Computer Algebra in Solving Chaffee-Infante Equation

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Communications in Theoretical Physics 2008年第4期49卷 825-828页

作者： XIE Fu-Ding LIU xiao-dan SUN xiao-Peng TANG Di Department of Computer Science Liaoning Normal University Dalian 116029 China Key Laboratory of Mathematics Mechanization AMSS the Chinese Aca~lemy of Sciences Beijing 100080 China

In this paper, a series of two line-soliton solutions and double periodic solutions of Chaffee-Infante equation have been obtained by using a new transformation. Unlike the existing methods which are used to find multiple soliton solutions of nonlinear partial differential equations, this approach is constructive and pure algebraic. The results found here are tested on computer and therefore their validity is ensured.

关键词： Chaffee-Infante equation two line-soliton solution double periodic solution

珠三角典型地区气态氨分布及其对PM_(2.5)贡献

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中国环境科学 2024年第9期44卷 4796-4804页

作者：黄国锋肖林海陈梓杰张涛钟庄敏方晓丹廖彤陈多宏广东省生态环境监测中心生态环境部环境保护区域空气质量监测重点实验室广东广州510308 广东省环珠江口气候环境与空气质量变化野外科学观测研究站广东广州510275 暨南大学环境与气候研究院广东广州511443 广东科迪隆科技有限公司广东广州510115

为探讨珠三角典型地区气态氮(NH_(3))对细颗粒物(PM_(2.5))的贡献,于2022年6月~2023年5月,在珠三角地区四个代表性城市选择了三个城市站点和一个郊区站点开展了NH_(3)的在线监测,并同步收集了水溶性离子、HNO_(3)、PM_(2.5)以及气象参... 详细信息

为探讨珠三角典型地区气态氮(NH_(3))对细颗粒物(PM_(2.5))的贡献,于2022年6月~2023年5月,在珠三角地区四个代表性城市选择了三个城市站点和一个郊区站点开展了NH_(3)的在线监测,并同步收集了水溶性离子、HNO_(3)、PM_(2.5)以及气象参数等资料.此基础上分析了NH_(3)的浓度水平特征和日变化特征,进一步评估了NH_(3)对PM_(2.5)的潜在贡献.结果表明,公园前(GYQ)、梅华(MH)、东城(DC)和鹤山花果山(HGS)的NH_(3)年均值分别为(5.74±3.00),(4.70±2.41),(5.09±2.26)和(4.17±1.95)μg/m^(3),除GYQ外,其余三站点NH_(3)季节变化均表现出秋季>春季>夏季>冬季的趋势.NH_(3)浓度日变化规律与温度相近,与相对湿度相反.经由修正的气体比率(AdjGR)评估,四个站点均处于富氨的条件下.随着PM_(2.5)污染浓度的上升,AdjGR逐渐下降,同时氨转化率(NHR)逐渐升高.除此之外,四个站点NHR>0.5的情况均主要发生在温度<25℃和相对湿度<70%的气象条件下.

关键词：气态氨细颗粒物气体比率二次无机气溶胶气粒转化