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三疣梭子蟹可食组织对无机砷的富集和释放

水产科学 2021年第4期40卷 492-500页

作者：赵艳芳宁劲松康绪明丁海燕翟毓秀尚德荣盛晓风中国水产科学研究院黄海水产研究所农业农村部水产品质量安全检测与评价重点实验室山东青岛266071

将全甲宽(140.02±15.14)mm经暂养净化的成熟雌三疣梭子蟹放在500 L的聚乙烯水族箱中,加入由砷酸钠和三氧化二砷母液配制成三价无机砷和五价无机砷质量浓度分别为0.01 mg/L和0.10 mg/L的海水。对照组为无机砷质量浓度为(1.18±0.16)μg/... 详细信息

将全甲宽(140.02±15.14)mm经暂养净化的成熟雌三疣梭子蟹放在500 L的聚乙烯水族箱中,加入由砷酸钠和三氧化二砷母液配制成三价无机砷和五价无机砷质量浓度分别为0.01 mg/L和0.10 mg/L的海水。对照组为无机砷质量浓度为(1.18±0.16)μg/L的过滤新鲜海水,不添加无机砷。半静态的暴露7 d富集试验中,每隔24 h换水1次,第1、3、5、7天随机取梭子蟹3只,立即解剖分离出肝胰腺、性腺和肌肉组织,于超低温冰箱中-80℃保存,用于测定3种可食组织中总砷的含量。28 d释放试验中,各试验箱中换成自然海水,每隔24 h完全换水1次,第7、14、21、28天随机取梭子蟹3只,立即解剖分离出上述3种可食组织,同样方法处理和测定,研究三疣梭子蟹在不同质量浓度三价无机砷和五价无机砷暴露7 d和释放28 d后的生物富集和释放转化规律。试验结果显示,三疣梭子蟹的可食组织对2种无机砷的富集能力较弱,肝胰腺组织中总砷含量在富集试验期间呈现先显著升高后降低的趋势,而在肌肉组织与性腺组织中均无明显的富集趋势,在释放试验期间,性腺和肝胰腺组织中总砷含量呈下降趋势,肌肉组织中总砷含量变化不明显。对照组三疣梭子蟹3种可食组织中砷的主要存在形态不同,肌肉与性腺中的砷主要以砷甜菜碱和二甲基砷形态存在,而肝胰腺中的砷主要以砷甜菜碱形态存在。试验结果表明,三疣梭子蟹对三价无机砷的生物利用度高于五价无机砷,无机砷主要积累在肝胰腺组织中,而肌肉与性腺组织中无无机砷累积。

关键词：三疣梭子蟹可食组织无机砷富集释放

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刚架拱桥人群荷载横向分布简化计算方法探讨

城市道桥与防洪 2007年第8期 58-60页

作者：张正权杨万里盛晓峰义乌市市政工程管理处浙江义乌322200

该文在弹性支承连续梁简化计算方法的基础上,参考杠杆法对边梁荷载横向分布影响线的处理手段,计算刚架拱桥人群荷载横向分布系数的方法,具有简单易懂、操作方便的特点。与利用空间有限元建模的计算结果比较,证明该方法计算准确,可行。

关键词：刚架拱桥荷载横向分布弹性支承连续梁简化计算方法有限元

Phase-only pattern synthesis based on gradient-descent optimization

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Journal of Systems Engineering and Electronics 2016年第2期27卷 297-307页

作者： Chengjun Lu Weixing sheng Yubing Han xiaofeng Ma School of Electronic and Optical Engineering Nanjing University of Science and Technology

By applying phase-only technique in array antenna pattern synthesis, antenna arrays can form desired patterns with the use of phase shifters only. A novel phase-only pattern synthesis algorithm is proposed for the passive phased array seeker. This algorithm synthesizes the main beam of the antenna pattern through least-squares approximation, thus minimizing the errors between the actual and the desired main beams. The synthesis problem can be solved by applying gradient-descent optimization. The item for suppressing side lobes is added to the above synthesis problem. To obtain a side lobe level as low as possible, the algorithm assigns different weights to different directions in the side lobe region. The algorithm is run repeatedly and the weights are adjusted adaptively according to the normalized power in the side lobe directions. Detailed examples are presented to demonstrate the accuracy and effectiveness of the proposed approach.

关键词： pattern synthesis phase-only gradient-descent adaptively

A New Wave of Hormone Research： Crosstalk Mechanisms

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Molecular Plant 2012年第5期5卷 959-960页

作者： xiaofeng Cui sheng Luan Deputy Editor-in-Chief Molecular Plant Editor-in-Chief Molecular Plant

Phytohormones regulate numerous aspects of plant growth, development, and responses to biotic and abiotic stress conditions. At least seven groups of phytohormones have been well characterized, including abscisic acid （ABA）, auxin, brassinosteroid （BR）, cytokinin （CK）, ethylene, gibberellin （GA）, and jasmonate （JA）. Hormone research in the past dec- ades has focused on elucidating signal transduction pathways from hormone perception to response and such effort has been well paid off by recent discoveries of almost all recep- tors for major classes of plant hormones.

关键词： Hormone Research Mechanism

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铜藻中无机元素的含量分析与食用安全评价

水产科学 2021年第1期40卷 109-115页

作者：赵艳芳尚德荣康绪明翟毓秀王联珠盛晓风丁海燕中国水产科学研究院黄海水产研究所农业农村部水产品质量安全检测与评价重点实验室山东青岛266071

分别运用电感耦合等离子体发射光谱法和电感耦合等离子体质谱法分析2018年10—12月采集于浙江、山东和辽宁沿海海域的铜藻样品中5种常量元素、14种微量元素以及16种稀土元素的含量,分析铜藻中As的形态,以阐明铜藻中无机元素的含量及其... 详细信息

分别运用电感耦合等离子体发射光谱法和电感耦合等离子体质谱法分析2018年10—12月采集于浙江、山东和辽宁沿海海域的铜藻样品中5种常量元素、14种微量元素以及16种稀土元素的含量,分析铜藻中As的形态,以阐明铜藻中无机元素的含量及其分布特征和食用安全性。结果显示,5种常量元素中,K的平均含量最高,为6.95×10^4 mg/kg(干质量),其次为Na的平均含量,达3.08×10^4 mg/kg,而P的平均含量最低,仅有0.15×10^4 mg/kg;对14种微量元素分析表明,铜藻含有丰富的Fe(889.12~1164.17 mg/kg)和Sr(1001.76~2010.13 mg/kg);Cd和Pb的含量很低,食用风险较低;铜藻中的砷主要以无机砷酸盐As(Ⅴ)形态存在,占总As含量的70%以上,食用风险较高。铜藻中总稀土元素含量为2.77~6.49 mg/kg,其中轻稀土元素的含量约为重稀土元素的2.0~2.5倍。综上,铜藻含有丰富的无机营养元素和稀土元素,具有较高的营养与医药保健价值。

关键词：铜藻无机元素稀土元素食用安全评价

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多元性管控在儿童辅助用药管理中的实践

中国医院用药评价与分析 2021年第8期21卷 1017-1020,1024页

作者：蔡和平邢文荣盛小凤尹传高安徽省儿童医院药剂科安徽合肥230000 安徽省儿童医院医务科安徽合肥230000

目的:规范辅助用药,加强辅助用药的合理应用。方法:安徽省儿童医院(以下简称“我院”)自2018年7月开始,由临床药师与医务科共同参与辅助用药的管控。回顾性分析干预后2018年第3季度至2019年第2季度我院患儿辅助用药的使用数据。结果:通... 详细信息

目的:规范辅助用药,加强辅助用药的合理应用。方法:安徽省儿童医院(以下简称“我院”)自2018年7月开始,由临床药师与医务科共同参与辅助用药的管控。回顾性分析干预后2018年第3季度至2019年第2季度我院患儿辅助用药的使用数据。结果:通过多元性管控干预,我院辅助用药销售金额占药品总销售金额的比例逐渐降低,由2018年第3季度的11.49%(7402133.19元/64396414.32元)降至2019年第2季度的6.50%(4530593.23元/69751165.47元);其中神经营养类药物的销售金额占药品总销售金额的比例降低最明显,由2018年第3季度的6.77%(4356664.72元/64396414.32元)降至2019年第2季度的4.38%(3053004.97元/69751165.47元),其他类药物的销售金额占药品总销售金额的比例稍有所波动,总体呈降低趋势;脑蛋白水解物口服液的用药频度最高,但未出现集中现象;按照成人限定日剂量(defined daily dose,DDD)计算限定日费用(daily drug cost,DDC),奥拉西坦注射液的DDC最高;根据我院儿童常用量DDD计算DDC,注射用磷酸肌酸的DDC最高。结论:多元性管控后,我院辅助用药的销售金额大幅降低,各项用药数据的波动也较一致,但仍需对个别品种进一步管控。

关键词：辅助用药用药频度限定日费用多元性合理用药

Shaped-Beam Pattern Synthesis Through the Construction of Weighted Generalized Rayleigh Quotient

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Chinese Journal of Electronics 2019年第1期28卷 207-214页

作者： YANG Yin WAN Chuan sheng Weixing HAN Yubing MA xiaofeng School of Electronic and Optical Engineering Nanjing University of Science and Technology

A novel shaped-beam pattern synthesis method of generating an arbitrary footprint pattern under an arbitrary array structure is proposed. The embedded element pattern information is included in the pattern model, and a new cost function composed of three optimization items which are sidelobe levels,mainlobe ripples and mainlobe gains is constructed through the model. During the optimization process,to further enhance the performance of the synthesized pattern, a weight matrix is designed and added to the optimization items, then the generalized Rayleigh quotient approximation method is used to obtain the final array element excitations. To illustrate the good performance of the provided method, several synthesis examples with different arrays and footprints are presented. Compared with other algorithms such as Weighted alternating reverse projection(WARP) method, the proposed method can achieve better results with lower sidelobe levels, smaller mainlobe ripples and less computational load.

关键词： Pattern synthesis Embedded element pattern Mutual coupling Generalized Rayleigh quotient approximation Arbitrary footprint

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运用体外全仿生消化法分析海藻中砷形态

中国渔业质量与标准 2012年第2期2卷 45-51页

作者：赵艳芳尚德荣宁劲松翟毓秀盛晓风中国水产科学研究院黄海水产研究所山东青岛266071

运用体外全仿生消化模型研究在唾液、胃肠无机物、有机物及消化酶作用下紫菜和海带中砷的主要形态及砷形态变化,采用高效液相色谱-电感耦合等离子体质谱法(HPLC-ICP-MS)联用技术进行砷形态分析,结果发现在胃肠全仿生消化提取液中,紫菜... 详细信息

运用体外全仿生消化模型研究在唾液、胃肠无机物、有机物及消化酶作用下紫菜和海带中砷的主要形态及砷形态变化,采用高效液相色谱-电感耦合等离子体质谱法(HPLC-ICP-MS)联用技术进行砷形态分析,结果发现在胃肠全仿生消化提取液中,紫菜中砷的主要形态为砷糖1(AsS1)(砷糖OH)和砷糖2(AsS2),海带中砷的主要形态为AsS1和二甲基砷酸(DMA);随着胃肠消化酶的作用,紫菜样品消化液中AsS2含量降低,砷糖OH含量升高,说明紫菜中部分未知砷糖2在消化酶作用下转化成砷糖1(砷糖OH);海带中砷糖1含量降低而DMA含量升高,说明海带中部分砷糖在消化酶作用下转化成DMA。在胃肠全仿生消化液作用下某些紫菜和海带中砷的主要形态与根据国标方法检测到的主要砷形态存在一定差异,因此,在对海藻中砷进行食用安全性评价时可以结合体外全仿生模型,分析砷的主要形态及生物可给性。

关键词：体外全仿生海藻砷形态分析 HPLC—ICP—MS

Assessing the uncertainties of phytoplankton absorption-based model estimates of marine net primary productivity

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Acta Oceanologica Sinica 2017年第6期36卷 112-121页

作者： TAO Zui MA sheng YANG xiaofeng WANG Yan State Key Laboratory of Remote Sensing Science Institute of Remote Sensing and Digital EarthChinese Academy of SciencesBeijing 100101China Beijing North-Star Digital Remote Sensing Technology Co.Ltd. Beijing 100120China State Environmental Protection Key Laboratory of Numerical Modeling for Environment Impact Assessment Beijing 100012China

Satellite-derived phytoplankton pigment absorption （aph） has been used as a key predictor of phytoplankton photosynthetic efficiency to estimate global ocean net primary production （NPP）. In this study, an aph-based NPP model （AbPM） with four input parameters including the photosynthetically available radiation （PAR）, diffuse attenuation at 490 nm （Ka（490））, euphotic zone depth （Zeu） and the phytoplankton pigment absorption coefficient （aph） is compared with the chlorophyll-based model and carbon-based model. It is found that the AbPM has significant advantages on the ocean NPP estimation compared with the chlorophyll-based model and carbon- based model. For example, AbPM greatly outperformed the other two models at most monitoring sites and had the best accuracy, including the smallest values of RMSD and bias for the NPP estimate, and the best correlation between the observations and the modeled NPPs. In order to ensure the robustness of the model, the uncertainty in NPP estimates of the AbPM was assessed using a Monte Carlo simulation. At first, the frequency histograms of simple difference （fi）, and logarithmic difference （~LOG） between model estimates and in situ data confirm that the two input parameters （Zeu and PAR） approximate the Normal Distribution, and another two input parameters （aph and Ka（490）） approximate the logarithmic Normal Distribution. Second, the uncertainty in NPP estimates in the AbPM was assessed by using the Monte Carlo simulation. Here both the PB （percentage bias）, defined as the ratio of ANPP to the retrieved NPP, and the CV （coefficient of variation）, defined as the ratio of the standard deviation to the mean are used to indicate the uncertainty in the NPP brought by input parameter to AbPM model. The uncertainty related to magnitude is denoted by PB and the uncertainty related to scatter range is denoted by CV. Our investigations demonstrate that PB of NPP uncertainty brought by all parameters with an annual mean of 5.5% covered a ran

关键词： marine net primary production phytoplankton pigment absorption satellite remote sensing uncertainty analysis Monte Carlo simulation