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Heavy Metal Distributions and Source Tracing in the Lacustrine Sediments of Dongdao Island,South China Sea

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Acta Geologica Sinica(English Edition) 2008年第5期82卷 1002-1014页

作者： LIU Xiaodong SUN Liguang YIN Xuebin wang yuhong Institute of Polar Environment University of Science and Technology of China Hefei Anhui 230026 National Institutes of Health Bethesda MD 20892 USA

The levels and depth distributions of As, Cd, Cu, Zn, Pb, Hg, Fe and Mn in two sediment cores DY2 and DY4 collected from the ＂Cattle Pond＂ of Dongdao Island, South China Sea, were determined and analyzed with the main objective to identify the sources of these elements and evaluate the corresponding sedimentological and geochemical processes. Lithological characters and sedimentary parameters such as LOI950℃, CaO, LOI550℃ and TOC indicate that the depth of 96 cm and 87 cm are the critical points for DY2 and DY4 cores, respectively. As, Cd, Cu, Zn, Hg and P are remarkably enriched in the ornithogenic sediments above the critical depth points; their concentration-versus-depth profiles are similar to those of TOC and LOI550℃; the ratios of As, Cd, Cu, Zn, Hg over Ca are significantly correlated with P/Ca. Statistical and comparative analyses of these elements＇ levels in the ornithogenic sediments of DY2 and DY4 strongly suggest that seabird droppings are the main source of these elements. Additionally, for the upper sediment layers of DY2 and DY4 cores, Fe oxide sorption mechanism, like organic matter, may also play an important role in the abundances of heavy metals. Heavy metal Pb has geochemical characteristics distinctly different from those of As, Cd, Cu, Zn, Hg and P, and its isotope composition indicates an origin of anthropogenic emissions from the surrounding countries. These geochemical characteristics in the orinithogenic sediments of Xisha Islands are compared with the studies in the remote Antarctic and Arctic regions.

关键词： heavy metals elemental geochemistry ornithogenic sediments Dongdao Island South China Sea

变应原特异性IgE阳性慢性阻塞性肺疾病临床特征分析

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中华健康管理学杂志 2024年第5期18卷 339-346页

作者：陈庆琳姚秀娟刘晓芳李然王玉红张希春首都医科大学附属北京同仁医院呼吸与危重症医学科北京100730

目的探讨血清变应原特异性IgE(SIgE)阳性慢性阻塞性肺疾病(慢阻肺)临床特征。方法本研究为回顾性队列研究,纳入存在过敏特征并完成血清SIgE检测的稳定期慢阻肺患者105例,均于2022年9月至2023年10月就诊于首都医科大学附属北京同仁医院... 详细信息

目的探讨血清变应原特异性IgE(SIgE)阳性慢性阻塞性肺疾病(慢阻肺)临床特征。方法本研究为回顾性队列研究,纳入存在过敏特征并完成血清SIgE检测的稳定期慢阻肺患者105例,均于2022年9月至2023年10月就诊于首都医科大学附属北京同仁医院呼吸与危重症医学科门诊,SIgE检测有≥1项阳性结果者归入SIgE阳性组(32例),SIgE均阴性者归入SIgE阴性组(73例)。比较两组患者实验室检查、肺功能、慢阻肺症状评分、过去1年中重度急性加重事件发生率及药物治疗的差异。分析慢阻肺患者SIgE阳性的危险因素,采用受试者工作特征(ROC)曲线下面积(AUC)分析诊断慢阻肺SIgE阳性的最佳预测值。结果与SIgE阴性组相比,SIgE阳性组合并鼻炎、鼻窦炎、鼻窦炎伴鼻息肉、湿疹及有药物或食物过敏史的占比更高,已戒烟占比更高,IgE高于正常界值的占比、IgE水平、外周血嗜酸性粒细胞百分比(EOS%)、EOS计数及呼出气一氧化氮(FeNO)水平均更高(均P2.5%诊断SIgE阳性的ROC曲线AUC值为0.647(95%CI:0.543~0.752),灵敏度和特异度分别为52.8%和73.1%。结论SIgE阳性慢阻肺临床症状重,急性加重风险高,治疗存在不足,EOS%升高是具有过敏特征慢阻肺患者出现SIgE阳性的危险因素,SIgE阳性慢阻肺符合变应性表型慢阻肺诊断标准,EOS%>2.5%对临床发现变应性表型慢阻肺具有提示意义。

关键词：肺疾病,慢性阻塞性变应原免疫球蛋白E 抗体特异性疾病特征

基于变分模态分解的卷积长短时记忆网络短期电力负荷预测方法

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现代电力 2024年第1期41卷 97-105页

作者：黄睿朱玲俐高峰王渝红杨亚兰熊小峰国网四川综合能源服务有限公司四川省成都市610021 四川大学电气工程学院四川省成都市610065

电力负荷序列易受多重外部因素影响而呈现复杂性,不利于精准预测。为此,提出一种基于变分模态分解(variational mode decomposition,VMD)的卷积神经网络和长短期记忆网络(convolutional neural network and long short-term memory netw... 详细信息

电力负荷序列易受多重外部因素影响而呈现复杂性,不利于精准预测。为此,提出一种基于变分模态分解(variational mode decomposition,VMD)的卷积神经网络和长短期记忆网络(convolutional neural network and long short-term memory network,CNN-LSTM)相结合的短期电力负荷并行预测方法。先采用VMD将负荷数据分解为规律性强的各本征模态函数(intrinsic mode function,IMF)及残差;再将各分量分别输入到各自对应的CNN-LSTM混合预测网络,获得各初始预测值,并将该值与由气候、日期类型等组合得到的相关因素特征集相结合,进一步得出修正预测值;最终,叠加各分量修正预测值即得到完整预测结果。在实际负荷数据上做验证分析,结果表明,考虑相关外部因素特征集后日负荷预测平均相对误差均值可降低2.18%。与几种常规负荷预测方法进行效果对比,验证了该方法的有效性和可行性。

关键词：短期负荷预测变分模态分解卷积神经网络长短期记忆网络相关因素特征集

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0.8~2 GHz单比特接收机的设计

现代信息科技 2024年第6期8卷 58-61页

作者：王玉红秦睢睢李兵南京航天工业科技有限公司江苏南京210001

文章设计的单比特接收机能在0.8~2 GHz频率范围内对侦收的雷达信号进行快速测频,并输出频率、保宽脉冲等相关信息,从而快速引导干扰设备进行干扰。该单比特接收机将测频结果用于引导干扰源,具有频率测量和频率码连续输出、连续波判别、... 详细信息

文章设计的单比特接收机能在0.8~2 GHz频率范围内对侦收的雷达信号进行快速测频,并输出频率、保宽脉冲等相关信息,从而快速引导干扰设备进行干扰。该单比特接收机将测频结果用于引导干扰源,具有频率测量和频率码连续输出、连续波判别、保宽脉冲输出和BIT自检等功能。单比特接收机的组成架构在满足瞬时宽带宽、高灵敏度和实时处理等主要性能指标的前提下,还具备各组成模块功能明确、控制独立、调试方便等优点。

关键词： 0.8~2 GHz 单比特接收机快速测频

Effects of acrous gramineus and its component, alpha-asarone, on apoptosis of hippocampal neurons after seizure in immature rats

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Neural Regeneration Research 2008年第1期3卷 19-24页

作者： Libin Yang Shulei Li Yanzhi Huang Jianmin Liang yuhong wang Department of Pediatrics the First Hospital of Jilin University Changchun 130021 Jilin Province China Department of Histology and Embryology Norman Bethune Medical School Jilin University Changchun 130021 Jilin Province China Department of Internal Medicine Children Hospital of Changchun City Changchun 130061 Jilin Province China Department of Neurology the First Clinical Hospital affiliated to Harbin Medicine University Harbin 150001 Heilongjiang Province China

BACKGROUND： α-asarone and acrous gramineus have been shown to play a necessary function in enhancing the reactivity and convulsant threshold to electric stimulation of immature rats. They have also been shown to effectively suppress epileptic seizures induced by pentylenetetrazol in young rats. However, the mechanisms for these roles have been still unclear. OBJECTIVE： To observe the effects in immature rats of acrous gramineus and α -asarone on apoptosis of hippocampal neurons after epileptic seizure at the protein level, and to analyze the mechanism for these effects. DESIGN： A randomized controlled animal experiment. SETTINGS： Department of Pediatrics, First Hospital of Jilin University; Department of Histology and Embryology, Norman Bethune Medical School of Jilin University; Department of Internal Medicine, Children＇s Hospital of Changchun City; Department of Neurology, First Clinical Hospital affiliated to Harbin Medical University. MATERIALS： Fifty 3-week old Wistar rats, 34-40 g, irrespective of gender, were provided by Gaoxin Research Center of Medical Animal Experiment, Changchun. The animals were treated according to the animal ethical standards. The following chemicals were used for this study： acrous gramineus powders or infusion （Batch No, 0307113, Tianjiang Medicine Company Limited, Jiangyin）, α-asarone tablets （Batch No. 030219, Tianwei Pharmaceutical Factory, Shenyang）, and phenobarbital sodium tablets （Batch No. 020608, Xinya Medicine Company Limited, Shanghai）. The animals were divided into five groups randomly. First, ten rats were chosen as the normal controls. The remaining rats were treated with i.p. injections of pentylenetetrazol to stimulate an epileptic model. METHODS： The experiments were performed at the Neurological Laboratory of the First Hospital of Jilin University between October and December 2004. The rats were treated with i.p. injections of pentylenetetrazol （60 mg/kg） to establish an epileptic model. According to Racine＇ s stand

关键词： epilepsy immature rats acrous gramineus α-asarone hippocampus apoptosis

不同温度处理对野罂粟丸粒化种子发芽率的影响

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耕作与栽培 2024年第1期44卷 13-16,32页

作者：王笑王士军王玉红张兆萍常瑛甘肃省农业工程技术研究院甘肃武威733006 甘肃省特种药源植物种质创新与安全利用重点实验室甘肃武威733006

罂粟种子体积小、质量小,导致其在农业生产中存在播种效率低、种子浪费严重等问题。种子丸粒化技术能够改变种子形状、扩大种子体积,使得小粒种子能够实现机械化精量播种;同时,实现种子带肥、带药下田,提高种子的抗性等。为此,本试验通... 详细信息

罂粟种子体积小、质量小,导致其在农业生产中存在播种效率低、种子浪费严重等问题。种子丸粒化技术能够改变种子形状、扩大种子体积,使得小粒种子能够实现机械化精量播种;同时,实现种子带肥、带药下田,提高种子的抗性等。为此,本试验通过对不同倍数的罂粟丸粒化种子进行发芽试验的测定和大田种植,从而筛选出最适的罂粟种子丸粒化倍数为3倍处理。同时,探讨了工厂化烘烤车间野罂粟丸粒化种子适宜的安全操作温度,进行了不同温度处理对野罂粟丸粒化种子的影响试验,试验得出,要保证野罂粟丸粒化种子发芽率不受影响,野罂粟丸粒化种工厂化烘烤车间在加热50 min以内时,加热温度应控制在50℃以内。

关键词：野罂粟温度发芽率丸粒化

孕晚期血清血小板反应蛋白-1、D-二聚体及金属蛋白酶组织抑制物-1水平对瘢痕子宫再次妊娠患者产后出血的预测价值

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新乡医学院学报 2024年第2期41卷 138-142页

作者：李相杰任艳芳王玉红张全华管文莉新乡医学院第一附属医院产科河南卫辉453100

目的探讨孕晚期血清血小板反应蛋白-1(THBS-1)、D-二聚体(D-D)及金属蛋白酶组织抑制物-1(TIMP-1)水平对瘢痕子宫再次妊娠患者产后出血(PPH)的预测价值。方法选择2020年6月至2022年8月新乡医学院第一附属医院收治的108例瘢痕子宫再次妊... 详细信息

目的探讨孕晚期血清血小板反应蛋白-1(THBS-1)、D-二聚体(D-D)及金属蛋白酶组织抑制物-1(TIMP-1)水平对瘢痕子宫再次妊娠患者产后出血(PPH)的预测价值。方法选择2020年6月至2022年8月新乡医学院第一附属医院收治的108例瘢痕子宫再次妊娠孕妇为研究对象,根据孕妇分娩后是否发生PPH分为PPH组(n=21)和非PPH组(n=87)。采集2组孕妇入院当天肘静脉血5 mL,应用酶联免疫吸附法检测2组孕妇血清THBS-1、D-D、TIMP-1水平。比较2组孕妇的基本临床资料及血清THBS-1、D-D、TIMP-1水平。采用多因素logistic回归分析瘢痕子宫再次妊娠孕妇发生PPH的影响因素,受试者操作特征(ROC)曲线分析血清THBS-1、D-D、TIMP-1水平对瘢痕子宫再次妊娠孕妇发生PPH的预测价值。结果PPH组人工流产次数≥2次、胎盘早剥、子宫切口撕裂、宫缩乏力、瘢痕厚度<0.3 cm占比及孕晚期血清THBS-1、D-D水平显著高于非PPH组,血清TIMP-1水平显著低于非PPH组(P<0.05)。宫缩乏力、D-D和THBS-1水平升高是瘢痕子宫再次妊娠孕妇PPH的独立危险因素(P<0.05),TIMP-1水平降低是瘢痕子宫再次妊娠孕妇PPH的保护因素(P<0.05)。血清THBS-1、D-D、TIMP-1联合预测瘢痕子宫再次妊娠孕妇PPH的曲线下面积大于三者单独预测(P<0.05)。结论孕晚期血清THBS-1、D-D、TIMP-1水平均可作为预测瘢痕子宫再次妊娠孕妇发生PPH的参考指标,且三者联合对瘢痕子宫再次妊娠孕妇发生PPH的预测效能更高。

关键词：产后出血血小板反应蛋白-1 D-二聚体金属蛋白酶组织抑制物-1 瘢痕子宫

Potential Applications of X-ray Fluorescence Core Scanner in Elemental Analyses of the Muddy Sediments on the Coastal Shelves of China and in Ecological Study

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Journal of Ocean University of China 2013年第4期12卷 619-623页

作者： ZHOU Xin SUN Liguang LIU Yi wang yuhong Institute of Polar Environment & School of Earth and Space Sciences University of Science and Technology of China Advanced Management Research Center 818 Fenghua Road Ningbo University

Large areas of muddy sediments on the coastal shelves of China provide important samples for studying climate and ecological changes. Analysis of a large number of such samples, which is essential for systematic study on environmental information recorded in mud areas because of complicated sedimentary environment and variable sedimentary rate, requires a fast and economical method. In this study, we investigated the potential of X-ray fluorescence core scanner （XRFS）, a fast analytical instrument for measuring the elemental concentrations of muddy sediments, and observed a significant correlation between the element concentrations of muddy sediments determined by regular X-ray fluorescence spectrometer （XRF） and XRFS, respectively. The correlations are mainly determined by excitation energy of elements, but also influenced by solubility of element ions. Furthermore, we found a striking link between A1 concentrations and marine-originated organic carbon （MOC）, a proxy of marine primary productivity. This indicates that MOC is partly controlled by sedimentary characteristics. Therefore, XRFS method has a good potential in fast analysis of a large number of muddy sediment samples, and it can also be used to calibrate MOC in ecological study of coastal seas.

关键词： X-ray fluorescence core scanner X-ray fluorescence spectrometer muddy sediment marine-originated organic carbon ecological study

Extreme precipitation events in East China and associated moisture transport pathways

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Science China Earth Sciences 2016年第9期59卷 1854-1872页

作者： ZHAO Yang XU XiangDe ZHAO TianLiang XU HongXiong MAO Fei SUN Han wang yuhong State Key Laboratory of Severe Weather Chinese Academy of Meteorological Sciences Beijing 100081 China Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Key Laboratory for Aerosol-Cloud-Precipitation of China Meteorological Administration Nanjing University of Information Science & Technology Nanjing 210044 China Institute of Ecological Environment and Agricultural Meteorology Chinese Academy of Meteorological Sciences Beijing 100081 China Guangxi Institute of Meteorological Disaster Mitigation Nanning 530022 China

Interannual variation of summer precipitation in East China, and frequency of rainstorms during the monsoon season from 1961 to 2010, are analyzed in this study. It is found that the two variables show opposite trends on a decadal time scale: frequency of rainstorms increases significantly after the 1990 s, while summer precipitation in East China decreases during the same period. Analysis of the spatial distribution of summer rainstorm frequency from 1961 to 2010 indicates that it decreases from the southeast to the northwest at the east edge of the large-scale topography associated with the plateaus. Spatial distribution of rainstorms with daily rainfall greater than 50 mm is characterized by a "high in the southeast and low in the northwest" pattern, similar to the staircase distribution of the topography. However, the spatial distribution of variation in both summer precipitation and frequency of extreme rainstorms under global warming differs significantly from the three-step staircase topography. It is shown that moisture characteristics of summer precipitation and extreme rainstorms during the monsoon season in East China, including moisture transport pathways, moist flow pattern, and spatial structure of the merging area of moist flows, differ significantly. Areas of frequent rainstorms include the Yangtze River Valley and South China. Column-integrated moisture transport and its spatial structure could be summarized as a "merging" of three branches of intense moist flows from low and middle latitude oceans, and "convergence" of column-integrated moisture fluxes. The merging area for moist flow associated with rainstorms in the high frequency region is located slightly to the south of the monsoonal precipitation or non-rainstorm precipitation, with significantly strong moisture convergence. In addition, the summer moist flow pattern in East China has a great influence on the frequency of extreme rainstorms. Moisture flux vectors in the region of frequent rai

关键词： Frequency of rainstorms Moisture transport Synoptic circulation Extreme rainstorms Synchronized variations Vortex structure