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Chinese Chemical Letters 2018年第6期29卷 973-976页

作者： maogui zhou Shiya Qin Zhenzhen Feng Chunxia Song Hua Zhang Wenshan Li Qing Wang Jianbo Liu Jin Huang Xiaohai Yang Kemin Wang State Key Laboratory of Chemo/Biosensing and Chemometrics College of Chemistry and Chemical Engineering Key Laboratory for Bio-Nanotechnology and Molecular Engineering of Hunan Province Hunan University School of Science Anhui Agricultural University

Apurinic/apyrimidinic endonuclease 1（APE1） plays an important role in protecting the fidelity of genetic material and is also a promising biomarker of cancers. Herein, a simple and sensitive fluorescent method for APE1 activity detection was designed based on host-guest interaction between β-cyclodextrin polymer（β-CDP） and pyrene. In this method, pyrene-labelled DNA probes（AP-S1 S2） and β-CDP functioned as fluorescent signal producer and enhancer, respectively. When APE1 was absent, pyrene on the AP-S1 S2 could not enter the cavity of β-CDP because of steric hindrance, leading to a weak fluorescence intensity/anisotropy. When APE1 was present, it would recognize and cleave AP site in APS1 S2, thus producing a dissociated pyrene-labelled oligonucleotide segment. Pyrene labelled at the 50 end of oligonucleotide segment could be easily trapped into the cavity of β-CDP via host-guest interaction, leading to a significant enhancement of fluorescence intensity/anisotropy. This assay offered a dynamic range of 0.05 U/m L–5 U/m L and an estimated detection limit of 0.05 U/m L. Furthermore,assessment of APE1 activity in He La cell extracts was successfully implemented, which hold the potential for APE1-related cancer diagnosis and biological researches.

关键词： APE1 Host-guest interaction Fluorescence β-Cyclodextrin polymer Pyrene

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基于线型激光的热轧带钢表面在线检测系统

北京科技大学学报 2008年第1期30卷 77-79,104页

作者：徐科周茂贵徐金梧杨朝霖周鹏高阳北京科技大学高效轧制国家工程研究中心北京100083

针对基于面阵CCD摄像机的热轧带钢表面缺陷检测系统所存在的问题,提出采用线阵CCD摄像机作为热轧带钢的表面图像采集装置,将激光线光源作为照明光源,解决了高温环境下的远距离均匀照明问题.采用这种图像采集方式可以使系统的精度达到0.... 详细信息

针对基于面阵CCD摄像机的热轧带钢表面缺陷检测系统所存在的问题,提出采用线阵CCD摄像机作为热轧带钢的表面图像采集装置,将激光线光源作为照明光源,解决了高温环境下的远距离均匀照明问题.采用这种图像采集方式可以使系统的精度达到0.5mm以上.针对热轧带钢表面存在的氧化铁皮、水及光照不均等问题,提出了对于不同缺陷类型建立单独的缺陷检测算法的思想.目前已经建立了纵裂与边裂的检测算法,对这两类缺陷的检出率达95%以上.

关键词：热轧带钢表面缺陷在线检测线型激光

Adaptive multiscale wavelet-guided periodic sparse representation for bearing incipient fault feature extraction

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Science China(Technological Sciences) 2024年第11期67卷 3585-3596页

作者： NIU maogui JIANG HongKai YAO RenHe School of Civil Aviation Northwestern Polytechnical UniversityXi’an 710072China

Currently, accurately extracting early-stage bearing incipient fault features is urgent and challenging. This paper introduces a novel method called adaptive multiscale wavelet-guided periodic sparse representation(AMWPSR) to address this issue. For the first time, the dual-tree complex wavelet transform is applied to construct the linear transformation for the AMWPSR *** transform offers superior shift invariance and minimizes spectrum aliasing. By integrating this linear transformation with the generalized minimax concave penalty term, a new sparse representation model is developed to recover faulty impulse components from heavily disturbed vibration signals. During each iteration of the AMWPSR process, the impulse periods of sparse signals are adaptively estimated, and the periodicity of the latest sparse signal is augmented using the final estimated period. Simulation studies demonstrate that AMWPSR can effectively estimate periodic impulses even in noisy environments, demonstrating greater accuracy and robustness in recovering faulty impulse components than existing *** validation through research on two sets of bearing life cycle data shows that AMWPSR delivers superior fault diagnosis results.

关键词： incipient fault feature extraction dual-tree complex wavelet transform generalized minimax concave penalty periodic sparse representation

Estimation of daily PM2.5 concentration and its relationship with meteorological conditions in Beijing

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Journal of Environmental Sciences 2016年第10期28卷 161-168页

作者： Qian Yin Jinfeng Wang maogui Hu Hoting Wong LREIS Institute of Geographic Sciences and Nature Resources Research Chinese Academy of Sciences Beijing 100101 China Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application Nanjing 210023 China

When investigating the impact of air pollution on health, particulate matter less than 2.5μm in aerodynamic diameter （PM2.5） is considered more harrnful than particulates of other sizes. Therefore, studies of PM2.5 have attracted more attention. Beijing, the capital of China, is notorious for its serious air pollution problem, an issue which has been of great concern to the residents, government, and related institutes for decades. However, in China, significantly less time has been devoted to observing PM2.5 than for PM10. Especially before 2013, the density of the PM2.5 ground observation network was relatively low, and the distribution of observation stations was uneven. One solution is to estimate PM2.5 concentrations from the existing data on PM10. In the present study, by analyzing the relationship between the concentrations of PM2.5 and PM10, and the meteorological conditions for each season in Beijing from 2008 to 2014, a U-shaped relationship was found between the daily maximum wind speed and the daily PM concentration, including both PM2.5 and PM10. That is, the relationship between wind speed and PM concentration is not a simple positive or negative correlation in these wind directions; their relationship has a complex effect, with higher PM at low and high wind than for moderate winds. Additionally, in contrast to previous studies, we found that the PM2.5/PM10 ratio is proportional to the mean relative humidity （MRH）. According to this relationship, for each season we established a multiple nonlinear regression （MNLR） model to estimate the PM2.5 concentrations of the missing periods.

关键词： PM10 concentrationPM2.5 concentration estimationWind speedWind direction

Optimization of Shanghai Marine Environmental Monitoring Sites in the Identification of Boundaries of Different Water Quality Grades

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Journal of Ocean University of China 2018年第4期17卷 846-854页

作者： FAN Haimei GAO Bingbo WANG Jinfeng QIN Xiaoguang LIU Pengxia HU maogui XU Peng East China Sea Environmental Monitoring Center State Oceanic AdministrationShanghai 201206China Beijing Research Center for Information Technology in Agricultur Beijing Academy of Agriculture and Forestry SciencesBeijing 100097China State Key Laboratory of Resources&Environmental Information System Institute of Geographic Sciences&Nature Resources ResearchChinese Academy of SciencesBeijing 1O0101China

Water quality is critical to ensure that marine resources and the environment are utilized in a sustainable manner. The objective of this study is therefore to investigate the optimum placement of marine environmental monitoring sites to monitor water quality in Shanghai, China. To improve the mapping or estimation accuracy of the areas with different water quality grades, the monitoring sites were fixed in transition bands between areas of different grades rather than in other positions. Following bidirectional optimization method, first, 18 candidate sites were selected by filtering out specific site categories. Second, three of these were, in turn, eliminated because of the rule defined by the changes in the areas of water quality grades and by the standard deviation of the interpolation errors of dissolved inorganic nitrogen(DIN) and phosphate(PO_4-P). Furthermore, indicator kriging was employed to depict the transition bands between different water quality grades whenever new sampling sites were added. The four optimization projects of the newly added sites reveal that, all optimized sites were distributed in the transition bands of different water grades, and at the same time in the areas where the historical sites were sparsely distributed. New sites were also found in the overlap region of different transition bands. Additional sites were especially required in these regions to discriminate the boundaries of different water quality grades. Using the bidirectional optimization method of the monitoring sites, the boundaries of different water quality grades could be determined with a higher precision. As a result, the interpolation errors of DIN and PO_4-P could theoretically decrease.

关键词： bidirectional optimization method boundaries of water quality grades Changjiang River Estuary and its adjacent areas transition bands indicator kriging

人工栽培堇叶碎米荠生物学特征及其营养成分比较

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中国野生植物资源 2018年第1期37卷 31-36页

作者：石爱华黄思勇陈体强金显平彭经寿姚茂桂周光龙恩施职业技术学院生物工程系湖北恩施445000 恩施职业技术学院硒营养研究所湖北恩施445000 福建省农业科学院食用菌研究所福建福州350014

目的:对人工驯化栽培的堇叶碎米荠进行生物学观察和营养成分分析,为蔬菜类新食品原料开发提供科学依据。方法:采用形态分类学和扫描电镜观察,描述和鉴定栽培植物;分析比较、大棚和露地补(富)硒栽培样品的营养成分。结果:栽培植物为堇叶... 详细信息

目的:对人工驯化栽培的堇叶碎米荠进行生物学观察和营养成分分析,为蔬菜类新食品原料开发提供科学依据。方法:采用形态分类学和扫描电镜观察,描述和鉴定栽培植物;分析比较、大棚和露地补(富)硒栽培样品的营养成分。结果:栽培植物为堇叶碎米荠(Cardamine violifolia ***),其花粉粒为橄榄球状,大小为13.48~16.72μm×33.45~36.77μm;干品中水分、还原糖、粗脂肪和粗纤维含量分别为7.10%~7.44%、3.7%~5.55%和8.0%~15.7%,含有较低的粗脂肪(0.82%~1.9%)、较高的蛋白质(17.0%~21.5%),氨基酸总量可达13.38%~14.07%,并含有丰富的钙、磷、铁、镁和锌等人体必需等常量和微量元素;正常补硒栽培硒含量为78.9~129μg/100 g,符合食品安全要求。结论:堇叶碎米荠的食用部位为抽苔期的嫩茎叶,可制成干品粉末后筛分去掉粗纤维可作为补硒的食品新原料。

关键词：堇叶碎米荠形态分类栽培植株营养成分新食品原料

Spectroscopic Studies on the Interaction of Asiatic Acid with Bovine Serum Albumin

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Chinese Journal of Chemistry 2011年第3期29卷 549-554页

作者： Yao, Di Ni, Shouhai Wen, maogui Bian, Hedong Yu, Qing Liang, Hong Chen, Zhenfeng Key Laboratory for Chemistry and Molecular Engineering of Medicinal Resources (Guangxi Normal University) Ministry of Education of China Guilin Guangxi 541004 China

Fluorescence spectroscopy, Fourier transform infrared （FT-IR） spectroscopy, circular dichroism （CD） and FT-Raman spectroscopy were employed to analyze the binding of the asiatic acid （AA） to bovine serum albumin （BSA） under simulative physiological conditions. Fluorescence data revealed that the fluorescence quenching of BSA by AA was the result of the formation of BSA-AA complex. The fluorescence quenching mechanism of BSA by AA was a static quenching procedure. According to the Van＇t Hoff equation, the thermodynamic parameters enthalpy change （△H0） and entropy change （△S0） for the reaction were evaluated to be --12.55 kJ·mol^-1 and 67.08 kJomol 1, respectively, indicating that hydrophobic and electrostatic interactions played a major role in stabilizing the complex. The influence of AA on the conformation of BSA has also been analyzed on the basis of FT-IR, CD and FT-Raman spectra.

关键词： bovine serum albumin asiatic acid secondary structure fluorescence spectroscopy fourier transforminfrared (FT-IR) circular dichroism raman spectroscopy

Expenditure of hospital care on cancer in China, from 2011 to 2015

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Chinese Journal of Cancer Research 2017年第3期29卷 253-262页

作者： Yue Cai Ming Xue Wanqing Chen maogui Hu Zhiwen Miao Lan Lan Rongshou Zheng Qun Meng Center for Health Statistics and Information National Health and Family Planning Commission National Central Cancer Registry National Cancer Center/Cancer Hospital Chinese Academy of Medical Sciences and Peking Union Medical College State Key Laboratory of Resources and Environmental Information System Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences West China School of Public Health Sichuan University

Objective: A solid understanding of levels and trends of spending on cancer is important to evaluate whether our healthcare resources were wisely spent and to prioritize future resources for cancer treatment and prevention. However, studies on economic burden of cancers in China are scant and the results are inconsistent. Methods: The Chinese hospital information database and nearly 350 million inpatient medical record data were used. As the ratios of cancer inpatient payments to total inpatient payments were mainly influenced by the grades and sites of hospitals, the estimates of payments of cancer inpatients in this study were stratified by hospital grades and provinces. Only the payments of cancer inpatients happened in grade 2, grade 3 and specialized cancer hospitals were included in the analyses. The total medical payments of cancers in China were estimated based on the ratios of outpatient payments to inpatient payments in specialized cancer hospitals. Results: From 2011 to 2015, the payments of cancer inpatients in China have increased by 84.1% and the total inpatient payments reached 177.1 billion RMB in 2015, accounting for 4.3% of the total health expenditure in China. Based on the ratio of outpatient payments to inpatient payments, the total payments on cancer treatments in China were estimated to be 221.4 billion RMB in 2015. Among different cancer types, the highest payments were the treatment of trachea, bronchus and lung cancer. The major cancer inpatient payments (67.1% in 2015) spent in grade 3 general hospitals and this ratio increased continually from 2011 to 2015. The expenditure of cancer treatments also varies by region with the major expenditure in the eastern region of China. Conclusions: This study estimated the total payments of cancer treatments in China and analyzed how the money was spent on cancer treatments in the recent 5 years, which would provide information for decision makings on the allocation of resources to service provisionin

关键词： Cancer payments expenditure economic burden

Captive Breeding of the Four-eyed Turtle(Sacalia quadriocellata)

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Asian Herpetological Research 2010年第2期1卷 111-117页

作者： HE Bin LIU Yuxiang SHI Haitao ZHANG Jie HU maogui MA Yonggang FU Lirong HONG Meiling WANG Jichao Fong J.Jonathan Parham F.James College of Life Sciences Hainan Normal University Chengdu Institute of Biology Chinese Academy of Sciences Museum of Vertebrate Zoology Department of Integrative BiologyUniversity of California at Berkeley Alabama Museum of Natural History University of Alabama

In 1998,a study on forty-five four-eyed turtles(Sacalia quadriocellata) was initiated to gather preliminary biological data of this species and to investigate the feasibility of its captive *** the following six years,no courtship behavior was found occurring in males and no oviposition in *** 2004 to 2007,two successful techniques were applied to initiate reproductive behavior:1) injecting exogenous reproductive hormones; and 2) reducing the stress of living in *** a result of the hormone treatments,courtship behavior and copulation were observed during September and October,***,no courtship displays were seen from the CK males,which were not treated with *** occurred between December and March,and the correlation was not significant between behavior of ovulation and food *** laid only one clutch of eggs each year,with 2.47 eggs(n=34,range=1–4) at average,and 84 eggs were totally obtained,of which 13 were damaged,52 were infertile and 19 *** the fertile eggs,nine were hatched with mean incubation period of 105.9 days(n=9,range=89–122 days) at temperature ranging from 24 to 27℃.

关键词： four-eyed turtle Sacalia quadriocellata captive breeding hormone stress conservation

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固体氧化物燃料电池数值仿真模型的建立

中南大学学报（自然科学版） 2019年第11期50卷 2633-2644页

作者：汤水张茂贵贾明刘宇中南大学冶金与环境学院

基于COMSOL Multi-physics 5.3a仿真平台,建立三维模型对固体氧化燃料电池进行数值计算。考虑板式固体氧化物燃料电池单体内部的气体流动、组分质量分数、电化学反应过程,研究不同工况下的气体分布、电流密度和极化情况,分析电池长度、... 详细信息

基于COMSOL Multi-physics 5.3a仿真平台,建立三维模型对固体氧化燃料电池进行数值计算。考虑板式固体氧化物燃料电池单体内部的气体流动、组分质量分数、电化学反应过程,研究不同工况下的气体分布、电流密度和极化情况,分析电池长度、工作温度、进气成分对固体氧化物燃料电池工作性能的影响。研究结果表明:固体氧化物燃料电池入口处气体质量分数较大,电化学反应速率也较快;在高电流密度下,入口氧气的质量分数会显著影响电池性能,而在低电流密度下,氧气质量分数不是影响电池电压的主要因素;当电池工作温度升高时,电池内部很多参数会发生变化。

关键词：固体氧化物燃料电池数值模拟模型电流密度气体分布