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Correlation Between Birth Defects and Dietary Nutrition Status in a High Incidence Area of China

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Biomedical and Environmental Sciences 2008年第1期21卷 37-44页

作者： BAO-YUAN ZHANG TING ZHANG lIANG-MING lIN FANG WANG RUO-lEI XIN XUE GU YU-NA HE DONG-MEI YU PEI-ZHEN lI qinG-SHAN ZHANG JIN ZHAO Yu-Fu qin XIU-FENG YANG GONG CHEN JU-FEN lIU XIN-MING SONG XIAO-YING ZHENG Capital Institute of Pediatrics Beijing 100020 China Chinese Center for Disease Control and Prevention Beijing 100050 China Department of Epidemiology Shanxi Medical University Taiyuan 030001 Shanxi China Center for Disease Control and Prevention of Shanxi Province Taiyuan 030012 Shanxi China Xinzhou Center for Disease Control and Prevention Xinzhou 034000 Shanxi China WHO Collaborating Center for Research in Reproductive Health and Population Science Institute of Population Research Peking University Beijing 100871 China

Objective To investigate the association between birth defects and dietary nutrient intake in a high risk area of China. Methods A dietary survey was performed and serum folic acid was measured in women whose pregnancy was affected by neural tube defects （NTDs） or unaffected by any birth defects （BDs） in Zhongyang and Jiaokou Counties in Shanxi Province of China. ResuIts The local average consumption of foods including dark green vegetables, fruits, fat and meat, and nutrient intake （e.g. energy, protein, retinol, riboflavin, vitamin E, and selenium） were lower than the national average level. In women of childbearing age, these regions, the intake of nutrients was much lower than the recommended nutrient intake （9%-77%）. The case-control dietary nutrition study of women whose pregnancy was affected by BDs （including NTDs and congenital heart defects） demonstrated that, in early pregnancy, adequate nutrition （i.e. eating meat, fresh vegetables, fruit more than once a week） was a protective factor, while eating germinated potatoes was a risk factor. The geometrical mean （pS- p95） of serum folic acid in women with NTD birth defects was 9.6 nmol/l （3.6, 23.03）, which was significantly lower than that in normal women （14.03 nmol/l）. Conclusion Women of childbearing age in the two counties of Shanxi Province, China, have a marked insufficient intake of some nutrients, especially folic acid, zinc, vitamins A and B12. This nutrient deficiency may be an important risk factor for the high prevalence of birth defects in these regions. Therefore, adequate dietary nutrition in early pregnancy can prevent BDs.

关键词： Birth defects Dietary survey Folic acid Nutrition status

Cloning and Sequence Analysis of lipoxygenase Gene cDNA from Cucumber Fruit (Cucumis sativus l.)

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分子植物育种 2007年第2期5卷 188-189页

作者： Z.K. Wang 　Z.W. qin　 X.Y. Zhou　 D.Y. Song Horticulture College of Northeast Agricultural University Harbin 150030 China

lipoxygenases are nonheme-iron-containing dioxygenases that catalyze the hydroperoxidation of unsatrated fatty acids containing a cis, cis-1,4-pentadiene structure producing hydroperoxy acids with conjugated dienes.

关键词：脂加氧酶基因克隆黄瓜种植

碱热耦合的膨润土-花岗岩岩屑混合物膨胀特性

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上海大学学报（自然科学版） 2022年第1期28卷 132-144页

作者：秦爱芳胡宏亮上海大学土木工程系上海 200444

在高放废物处置库的运营过程中,核废料的衰变热和混凝土老化产生的碱性孔隙水均会对缓冲回填材料的工作性能产生影响.为了研究碱热耦合对缓冲回填材料膨胀特性的影响,采用高庙子(Gaomiaozi,GMZ)膨润土和花岗岩岩屑混合材料,选用NaOH溶... 详细信息

在高放废物处置库的运营过程中,核废料的衰变热和混凝土老化产生的碱性孔隙水均会对缓冲回填材料的工作性能产生影响.为了研究碱热耦合对缓冲回填材料膨胀特性的影响,采用高庙子(Gaomiaozi,GMZ)膨润土和花岗岩岩屑混合材料,选用NaOH溶液模拟碱性孔隙水,利用水浴锅提供恒温溶液,并将溶液在自主研制的耐腐蚀固结仪中不断循环,分别开展25和50℃两种温度以及0.1、0.5和1.0 mol/l 3种碱性溶液浓度下的膨胀力试验,获得了各试样的膨胀力时程曲线.试验结果表明:当温度相同时,试样的最大膨胀力和稳定膨胀力均随碱性溶液浓度的增加而降低;当同一浓度碱性溶液入渗时,试样的最大膨胀力和稳定膨胀力均随掺岩率的增大而降低;相同掺岩率及入渗碱性溶液浓度的试样的最大膨胀力和稳定膨胀力均随温度的升高而降低.碱性溶液对膨胀力的衰减程度随溶液浓度的增加而增大,随温度的升高而增大.对于膨润土-花岗岩岩屑混合物,在相同入渗溶液浓度和相同反应温度下,膨胀力衰减率随掺岩率的增大而降低.

关键词：碱热耦合膨润土花岗岩岩屑膨胀力掺岩率

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采用电阻链滤波的变压器过励磁谐波抑制方法

厦门理工学院学报 2022年第1期30卷 16-21页

作者：吕志盛赵洪覃潘琦厦门理工学院电气工程与自动化学院福建厦门361024

为解决负荷低谷时段、电压偏高情况下变电站谐波指标超出国家标准问题,由变压器铁芯的励磁原理出发分析谐波的产生机理;利用PSCAD平台上搭建的变电站仿真模型,得到不同额定磁密、工作电压、电网阻抗特性下的5、7次谐波含有率变化特性;... 详细信息

为解决负荷低谷时段、电压偏高情况下变电站谐波指标超出国家标准问题,由变压器铁芯的励磁原理出发分析谐波的产生机理;利用PSCAD平台上搭建的变电站仿真模型,得到不同额定磁密、工作电压、电网阻抗特性下的5、7次谐波含有率变化特性;提出利用单调谐滤波器过滤变压器产生的主要谐波分量,通过电阻阻尼特性消除滤波器谐振现象的变压器过励磁谐波抑制方法。YNd11和Dyn112种类型的变压器谐波抑制效果仿真分析结果表明,带电阻链的单调滤波器组能有效抑制变压器产生的5、7次谐波分量,抑制后的总谐波含量降至国家标准允许范围内,滤波方法有效。

关键词：变压器过励磁谐波谐波抑制电阻链滤波器组

The effect of frequency on velocity and attenuation in Zr41.2Ti13.8Cu12.5Ni10.0Be22.5bulk metallic glass under high pressure

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The effect of frequency on velocity and attenuation in Zr41....

产业协同发展与城市全要素生产率——中国南北差异视角下的实证检验

18th International Conference on High Pressure Science and Technology

作者： Wang Ruiu li Fengying Wang Weihua qin zhicheng Institute of Physics Chinese Academy of Sciences Beijing 100080 China

＜正＞ Using the pulse echo overlap and the pulse superposition methods, the acoustic velocities V1, Vs and attenuation α1 , αs of ***12.5Ni10.0Be22.5 bulk metallic glass have been measured below 2GPa with 10 MHz and 20MHz carry frequency, respectively. The results reveal that V1 and Vs increase linearly with increasing pressure （P）, the slope of V1-P curve decreases with increasing frequency, one of VS-P is on the contrary. By comparison, the change of α*** αs, with pressure and frequency is more complex. The effects of frequency on velocity and attenuation under high pressure are discussed. The amorphous nature of the Zr/Ti BMG sample was ascertained by x-ray diffraction differential scanning calorimetry, transmission electron microscopy and small angle neutron scattering. The pulse echo overlap [2]（PEO） and pulse superposition [3]（PSP） are used to measure the travel time through the sample. Fig.l reveals that both of V1 and Vs increase linearly with pressure up to 2GPa because Zr/Ti BMG exhibits as a homogeneous elastic successive solid under compressed state. The slope of Vi-P curve decreases slightly when the carry frequency is increased from 10 MHz to 20 MHz, but one of VS-P increases. It means slight dispersion of sound and the modulus stiffness for Zr/Ti BMG under hydrostatic pressure. Fig.2 reveals that α1 and αs increase monotonously with pressure up to *** changes of longitudinal modes （V, and α1） are much large than that of shear modes （Vs and αs ） either with 10 MHz or 20 MHz, and α1 , αs increase with the frequency. The energy loss relates with frequency[7] and the longitudinal velocity. Bulk modulus B and its pressure derivative B’ of Zr/Ti BMG can be obtained, they are 114.75GPa and 4.059, respectively. So isothermal Murnaghan equation of state can be written in the following P = （Bo/B’0）[（Vo/V） B’0-1]= 28.27[（V0/V）4.059-l] Here V is volume.

关键词： velocity attenuation frequency metallic glass high pressure

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企业经济 2021年第1期40卷 82-90页

作者：马强秦琳贵辽宁石油化工大学经济管理学院辽宁抚顺113001 北京大学政府管理学院北京100871

制造业和生产性服务业的协同发展是中国经济提质增效的重要途径。使用2001-2018年的中国城市面板数据,测算了产业协同度,并考察了产业协同发展和全要素生产率的关系。结果表明:研究期内,中国城市整体及南方和北方的产业协同度呈现上升态... 详细信息

制造业和生产性服务业的协同发展是中国经济提质增效的重要途径。使用2001-2018年的中国城市面板数据,测算了产业协同度,并考察了产业协同发展和全要素生产率的关系。结果表明:研究期内,中国城市整体及南方和北方的产业协同度呈现上升态势,但存在明显区域差异,北方的产业协同度低于南方;在南方和北方,产业协同发展可显著提升全要素生产率,影响全要素生产率的作用机制在南方和北方存在差异;学习机制、互补机制和竞争机制可通过促进技术进步和提高技术效率共同推动全要素生产率增长,但南方和北方的影响机制存在显著差异。最后从发挥市场机制、完善保障体系和加快北方地区发展等方面给出了对策建议。

关键词：制造业生产性服务业协同发展全要素生产率

无电沉积法制备硼掺杂石墨烯负载钯纳米颗粒催化剂及对过氧化氢的电化学检测

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分析试验室 2022年第9期41卷 1065-1069页

作者：胡娅琪张博姚琳秦蓓西安医学院药学院西安710021 西安医学院药物研究所西安710021

利用硼掺杂石墨烯的大π共轭结构和还原性,以硼掺杂石墨烯为还原剂和稳定剂,通过无电沉积法制备硼掺杂石墨烯负载钯纳米颗粒催化剂。钯纳米颗粒尺寸约为6.5 nm,均匀地分散在硼掺杂石墨烯表面。将此催化剂修饰在玻碳电极表面,制备得到的... 详细信息

利用硼掺杂石墨烯的大π共轭结构和还原性,以硼掺杂石墨烯为还原剂和稳定剂,通过无电沉积法制备硼掺杂石墨烯负载钯纳米颗粒催化剂。钯纳米颗粒尺寸约为6.5 nm,均匀地分散在硼掺杂石墨烯表面。将此催化剂修饰在玻碳电极表面,制备得到的电化学传感器对H_(2)O_(2)具有良好的电化学催化效果,对H_(2)O_(2)检测具有较宽的线性范围(2.5~300μmol/l)及较低的检出限(830 nmol/l),并成功的应用于实际样品牛奶中H_(2)O_(2)的检测。

关键词：硼掺杂石墨烯钯纳米颗粒电化学催化过氧化氢

Exogenous levodopa Increases the Neuro-retinal Dopamine of Guinea Pig Myopic Eyes in vitro

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Eye Science 2011年第4期26卷 211-216页

作者： Junfeng Mao Shuangzhen liu Wenjuan qin Qian Xiang Xiaoying Wu Department of Ophthalmology Xiangya Hospital of Central South University Changsha 410008 China

Purpose:In our previous work,it has been shown that intraperitoneal injection of l-DOPA can inhibit the development of occlusion myopia in guinea pigs,and increase levels of retinal *** aim of this study was to investigate whether exogenous l-DOPA can be converted into dopamine in cultured retina of guinea pig eyes subjected to visual deprivation,and to evaluate whether müller cells are involved in the processing of retinal dopamine induced by ***:Fifty-eight guinea pigs were randomly divided into 2 groups at the age of 4 weeks:normal control and visual *** deprivation was induced with translucent eye shields over the right eye,and lasted for ten *** curvature,refraction and axial length were measured in all *** vitro,neuro-retina and müller cell were cultured,and l-DOPA was added to the culture medium at three concentrations:1 μM,10 μMand 100 μ***,dopamine content was evaluated by high-performance liquid chromatography,and apoptotic cells were identified by TUNEl ***:Ten days of occlusion caused the affected eyes to elongate and become myopic in guinea *** with the deprivation group,10 μMl-DOPA treament significantly raised dopamine content in cultured retina and müller cells (Pl-DOPA treatment caused no increase in dopamine levels(P>0.05).Apoptotic nuclei were detected in the ganglion cell layer (92.5%±8.3%) and inner nuclear layer (46.8%±9.1%)of cultured retina treated with 100 μ***,100 μMl-DOPA also caused apoptosis of retinal müller cells,at a mean rate of 59.4 ±11.3%.Conclusion:.Our results suggest that exogenous l-DOPA can cause an increase in retinal dopamine in form-deprived guinea pig eyes in vitro,and that müller cells are involved in the increase in retinal dopamine.

关键词：神经节细胞体外培养左旋多巴多巴胺视网膜近视眼外源性豚鼠

Pyrite depression in marmatite flotation by sodium glycerine-xanthate

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Transactions of Nonferrous Metals Society of China 2011年第5期21卷 1161-1165页

作者：何名飞覃文庆黎维中曾科中南大学资源加工与生物工程学院长沙410083

The depression of pyrite in marmatite flotation by sodium glycerine-xanthate （SGX） was investigated through microflotation, zeta potential and adsorption measurements. The flotation tests of mineral show that in the presence of SGX, marmatite can be activated by Cu^2＋ and shows good flotability, while pyrite cannot be activated and therefore shows poor flotability. At the pH value range from 4 to 11, the flotation selectivity between marmatite and pyrite is obvious when the SGX concentration is below 50 mg/l. The depression mechanism of SGX on sulfide minerals is discussed based on zeta potential and adsorption isotherm. Zeta potential measurement demonstrates that in the presence of Cu^2＋, SGX can strongly adsorb on the surface of pyrite, while it cannot adsorb on the surface of marmatite. The results of adsorption isotherms show that the adsorption density of SGX on pyrite is greater.

关键词： flotation sodium glycerine-xanthate marmitite pyrite