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Biases of estimated signals in x-ray analyzer-based imaging

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Chinese Physics B 2020年第6期29卷 571-576页

作者： Jianlin Xia Wen Xu Ruicheng Zhou xiaomin shi Kun Ren Heng Chen Zhili Wang School of Electronic Science&Applied Physics Hefei University of TechnologyHefei 230009China

Recently,a novel three-image algorithm has been proposed to retrieve the sample’s absorption,refraction,and scattering properties in x-ray analyzer-based *** feasibility of the three-image algorithm was validated by synchrotron radiation ***,it is unclear yet whether the estimated refraction and scattering signals are biased or not and how the analyzer angular position affects the biases in the estimated *** this purpose,the biases of the extracted refraction and scattering signals are theoretically derived for the three-image *** theoretical models are further confirmed by numerical *** results show that both the estimated refraction and scattering signals are biased,and the biases are strongly dependent on the analyzer angular ***,the biases also show dependence on the sample’s refraction and scattering properties *** results can be used as general guidelines to optimize experimental parameters for bias reduction and accurate imaging of different features within the sample.

关键词： x-ray imaging analyzer-based imaging three-image algorithm

Plasma N-terminal pro-brain natriuretic peptide levels in elderly patients with isolated diastolic dysfunction

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Journal of Geriatric Cardiology 2005年第4期2卷 211-215页

作者： Yixin SONG Qing LIN xiaomin shi Yunyun QI Department of Geriatric Medicine First Hospital of Beijing University Beijing 100034 China Department of Geriatric Medicine First Hospital of Beijing University Beijing 100034 China Department of Geriatric Medicine First Hospital of Beijing University Beijing 100034 China Department of Geriatric Medicine First Hospital of Beijing University Beijing 100034 China

Objective To investigate plasma N-terminal pro-brain natriuretic peptide (NT-BNP) levels and to assess their clinical significance in elderly patients with isolated diastolic dysfunction. Methods Plasma NT-BNP level were measured by electrochemiluminescence immunoassay in 34 symptomatic patients (Group 1), 34 asymptomatic patients (Group 2) with isolated diastolic dysfunction, and in 16 elderly healthy subjects (control group, Group 3), serving controls. Colored Doppler echocardiography was performed to evaluate the patients' cardiac structures and functions. Results The plasma NT-BNP level in Group 1 was significantly higher than those in Group 2 and Group 3 and increased with the severity of heart failure. There was no significant difference of plasma NT-BNP levels between Group 2 and Group 3 (p>0.05). A NT-BNP value of 102.75 pg/mL showed a sensitivity of 88.2%, a specificity of 87.5%, and an accuracy of 88.1% for diagnosing diastolic dysfunction. Patients with restrictive filling pattern on echocardiography had higher NT-BNP levels than those of impaired relaxation pattern (1961.2±304.9 versus 460.1±92.7pg/mL, p<0.001). Conclusion The elevation of plasma NT-BNP level in elderly patients with isolated diastolic dysfunction correlates with the severity of their diastolic abnormalities. The level of plasma NT-BNP has an important clinical value in the diagnosis of elderly patients with isolated diastolic dysfunction.

关键词： elderly isolated diastolic dysfunction N-terminal pro-brain natriuretic peptide echocardiography

Adsorption of atrazine by natural organic matter and surfactant dispersed carbon nanotubes

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Journal of Environmental Sciences 2010年第8期22卷 1195-1202页

作者： Baoyou shi, Xiaoyan Zhuang, xiaomin Yan, Jiajuan Lu, Hongxiao Tang State Key Laboratory of Environmental Aquatic Chemistry, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China. [a] State Key Laboratory of Environmental Aquatic Chemistry Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China

The aggregation and dispersion behaviors of carbon nanotubes （CNTs） can regulate the environmental spread and fate of CNTs, as well as the organic pollutants adsorbed onto them. In this study, multi-walled carbon nanotubes （MWNTs） and single-walled carbon nanotubes （SWNTs） were surface modified with humic acids from different sources and with surfactants of different ionic types. The dispersion stability of surface modified CNTs was observed by UV-Vis spectrophotometry. The effect of humic acid and surfactant dispersion on the adsorption of atrazine by CNTs was investigated by batch equilibrium experiments. Both humic acid and surfactant could effectively disperse MWNTs, but not SWNTs, into stable suspensions under the studied conditions. Surface modified CNTs had a greatly reduced capacity for adsorption of atrazine. The inhibitory effect of peat humic acid was relatively stronger than that of soil humic acid, but the two surfactants had a similar inhibitory effect on atrazine adsorption by the two CNT types. Increases in surfactant concentration resulted in rapid decreases in the adsorption of atrazine by CNTs when the surfactant concentration was less than 0.5 critical micelle concentration.

关键词： carbon nanotubes adsorption dispersion atrazine

Modified Technique of Orthotopic Liver Transplantation in Rats

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器官移植内科学杂志 2008年第1期3卷 23-26页

作者： xiaomin shi Yongzhao shi Zhiren Fu Xianxing Li Guoshan Ding Hong Fu Organ Transplantation Institute of PLA Changzheng Hospital Second Military Medical University Shanghai 200003 China

Trend of gastrointestinal and liver diseases in China: Results of the Global Burden of Disease Study, 2019

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中华医学杂志(英文版) 2024年第19期137卷 2358页

作者： Tang Xiaowei Wang Ping Huang Shu Peng Jieyu Zhang Wei shi xiaomin shi Lei Zhong Xiaolin Lyu Muhan Zhou Xian Linghu Enqiang Department of Gastroenterology The First Medical Center of Chinese PLA General Hospital Beijing China Department of Gastroenterology The Affiliated Hospital of Southwest Medical University Luzhou Sichuan China Department of Nuclear Medicine Nuclear Medicine and Molecular Imaging Key Laboratory of Sichuan Province Luzhou Sichuan China Department of Gastroenterology Lianshui County People’s Hospital Huaian Jiangsu China Department of Gastroenterology Lianshui People’s Hospital of Kangda College Affiliated to Nanjing Medical University Huaian Jiangsu China

Background: China is one of the countries with the largest burden of gastrointestinal and liver diseases (GILD) in the world. The GILD constitutes various causes of mortality and disability. The study aimed to investigate the trend of GILD in China using the Global Burden of Diseases Study 2019 (GBD 2019) data resources from 1990 to ***: The data on the age-standardized mortality rates (ASMR) and disability-adjusted life years (DALYs) for GILD in China from 1990 to 2019 were collected from the GBD 2019 data resources. Furthermore, the ranking of the main causes of deaths and DALYs, as well as the trends of ASMR, DALYs, years of life lost (YLLs), and years of life lost due to disability (YLDs) per 1,000,000 in GILD were ***: The ASMR and DALYs for stomach cancer, liver cancer, and esophageal cancer, which ranked top three among the GILDs from 1990 to 2019, were gradually decreasing. Significant decreases in the ASMR and DALYs were found in diarrheal diseases and acute hepatitis (A, E, and C). However, noteworthy increases were found in those of colon and rectum cancer (CRC) and pancreatic cancer. Trend of DALYs, mortality, and YLLs rates for most of GILD were decreasing from 1990 to 2019, except the burden of CRC and pancreatic cancer with an increasing trend. The DALYs, mortality and YLLs of most GILD diseases showed decreasing trends from 1990 to 2019, except the burden of CRC and pancreatic cancer with an increasing ***: The result of the GBD 2019 showed that the rates of most GILDs decreased in China; however, gastrointestinal and liver cancer, such as stomach cancer still held the top ranking. Furthermore, the shift from infectious diseases to non-communicable causes among GILD burden is occurring.

关键词： Gastrointestinal diseases Liver diseases Global Burden of Disease Mortality Disability-adjusted life years China

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基于非支配排序遗传算法的细纱工艺参数优化

纺织学报 2022年第1期43卷 80-88页

作者：邵景峰石小敏西安工程大学管理学院陕西西安710048

为了实现细纱生产工艺参数优化,解决细纱生产过程中高能耗问题,提出了一种基于非支配排序遗传算法的细纱工艺参数多目标优化方法。通过分析细纱生产工艺流程,确定了影响细纱成纱质量与能耗的工艺参数,提取了评价成纱质量的关键质量评价... 详细信息

为了实现细纱生产工艺参数优化,解决细纱生产过程中高能耗问题,提出了一种基于非支配排序遗传算法的细纱工艺参数多目标优化方法。通过分析细纱生产工艺流程,确定了影响细纱成纱质量与能耗的工艺参数,提取了评价成纱质量的关键质量评价指标,结合灰色关联理论将质量评价指标转化为综合质量指标,利用二阶响应曲面法拟合工艺参数与综合质量指标、碳排放量之间的关联关系,构建了细纱工艺参数多目标优化模型,并采用非支配排序遗传算法对模型进行寻优,得到了最佳工艺参数。结果证明:在优化后的工艺条件下,细纱生产过程中各项质量评价指标值较初始值均得到改善,碳排放量平均减少5.77%。

关键词：多目标寻优工艺优化碳排放成纱质量非支配排序遗传算法

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我国大气污染与人群健康关系研究进展

中华预防医学杂志 2019年第1期53卷 4-9页

作者：阚海东施小明复旦大学公共卫生学院上海200032 中国疾病预防控制中心环境与健康相关产品安全所北京100021

大气污染作为我国主要的环境与健康问题之一,已引起社会各界的广泛关注。本文分别从大气污染的急性健康效应研究、慢性健康效应研究、疾病负担和干预研究的角度,回顾了我国大气污染与人群健康研究的进展,并对未来几年我国该领域的研究... 详细信息

大气污染作为我国主要的环境与健康问题之一,已引起社会各界的广泛关注。本文分别从大气污染的急性健康效应研究、慢性健康效应研究、疾病负担和干预研究的角度,回顾了我国大气污染与人群健康研究的进展,并对未来几年我国该领域的研究方向进行了展望。

关键词：空气污染干预性研究患病代价急性效应慢性效应

Net ecosystem CO_2 exchange and controlling factors in a steppe——Kobresia meadow on the Tibetan Plateau

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Science China Earth Sciences 2006年第S2期49卷 207-218页

作者： shi Peili, SUN xiaomin, XU Lingling, ZHANG Xianzhou, HE Yongtao, ZHANG Dongqiu & YU Guirui Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China Graduate University of Chinese Academy of Sciences, Beijing 100039, China 1. Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China2. Graduate University of Chinese Academy of Sciences Beijing 100039 China

Knowledge of seasonal variation of net ecosystem CO2 exchange (NEE) and its biotic and abiotic controllers will further our understanding of carbon cycling process, mechanism and large-scale modelling. Eddy covariance technique was used to measure NEE, biotic and abiotic factors for nearly 3 years in the hinterland alpine steppe--Korbresia meadow grassland on the Tibetan Plateau, the present highest fluxnet station in the world. The main objectives are to investigate dynamics of NEE and its components and to determine the major controlling factors. Maximum carbon assimilation took place in August and maximum carbon loss occurred in November. In June, rainfall amount due to monsoon climate played a great role in grass greening and consequently influenced interannual variation of ecosystem carbon gain. From July through September, monthly NEE presented net carbon assimilation. In other months, ecosystem exhibited carbon loss. In growing season, daytime NEE was mainly controlled by photosynthetically active radiation (PAR). In addition, leaf area index (LAI) interacted with PAR and together modulated NEE rates. Ecosystem respiration was controlled mainly by soil temperature and simultaneously by soil moisture. Q10 was negatively correlated with soil temperature but positively correlated with soil moisture. Large daily range of air temperature is not necessary to enhance carbon gain. Standard respiration rate at referenced 10℃(R10) was positively correlated with soil moisture, soil temperature, LAI and aboveground biomass. Rainfall patterns in growing season markedly influenced soil moisture and therefore soil moisture controlled seasonal change of ecosystem respiration. Pulse rainfall in the beginning and at the end of growing season induced great ecosystem respiration and consequently a great amount of carbon was lost. Short growing season and relative low temperature restrained alpine grass vegetation development. The results suggested that LAI be usually in a low le

关键词： Tibetan Plateau alpine steppe--Kobresia meadow NEE ecosystem respiration PAR soil moisture temperature response LAI eddy covariance.

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莱姆病的实验室诊断及研究进展

中华检验医学杂志 2019年第10期42卷 890-893页

作者：史晓敏黄婷北京大学第一医院检验科北京100034

莱姆病是由硬蜱叮咬传播的一种自然疫源性人兽共患病,其病原为多种基因型的伯氏疏螺旋体。莱姆病的临床表现复杂多样,容易出现误诊,实验室检测对该病的诊断具有重要的指导意义。本文对莱姆病的临床诊断现状及相关检测的研究新进展进行... 详细信息

莱姆病是由硬蜱叮咬传播的一种自然疫源性人兽共患病,其病原为多种基因型的伯氏疏螺旋体。莱姆病的临床表现复杂多样,容易出现误诊,实验室检测对该病的诊断具有重要的指导意义。本文对莱姆病的临床诊断现状及相关检测的研究新进展进行了阐述。

关键词：伯氏疏螺旋体血清学检测聚合酶链式反应免疫聚合酶链式反应代谢组学