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Modulation by Biogenic Amines for the Hemocyte Count and Prophenoloxidase Exocytosis via Receptors in Litopenaeus vannamei

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Journal of Ocean University of China 2011年第4期10卷 425-432页

作者： PAN luqing liu Huijie YU Jinhong Department of Aquaculture the Key Laboratory of MaricultureMinistry of EducationOcean University of ChinaQingdao 266003P.R.China

Hemocyte counts and phenoloxidase(PO)activity were examined after hemolymph being incubated in dopamine(DA),noradrenaline(NE)and serotonin(5-HT).Results showed that all the three biogenic amines(BAs)had a significant impact on total hemocyte count(THC),differential hemocyte count(DHC),and intracelluar and extracelluar phenoloxidase(PO)*** these Bas,DA had the strongest effect on the above parameters,whereas 5-HT had the least *** with D1 receptor antagonist SCH23390,D2 receptor antagonist Sulpiride and 1:1 admixture of the two could significantly inhibit the effect of DA on these ***23390 showed a stronger inhibitory effect than Sulpiride,and the admixture exhibited the strongest *** results suggested that the change of hemocyte count and activation of prophenoloxidase(proPO)system in Litopenaeusvan-namei hemocyte can be regulated by BAs,and DA modulates the two parameters via its receptors.

关键词： biogenic amine dopamine receptor hemocyte Litopenaeus vannamei prophenoloxidase system

Immunotoxicity Effect of Benzo[α]Pyrene on Scallop Chlamys farreri

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Journal of Ocean University of China 2009年第1期8卷 89-94页

作者： ZHANG Lin PAN luqing liu Jing The Key Laboratory of Mariculture Ministry of Education Ocean University of China Qingdao 266003 P. R. China

The toxic effects of benzo[α]pyrene （B[α]P） at different concentrations （0.1, 0.5, 1, 2.5 and 7.5 μgL^-1） on scallop （Chlamys farreri） immune system were studied. The results showed that B[α]P had significant toxic effects on the haemocyte counts, neutral red uptake, phagocytosis, bacteriolytic and antibacterial activity （P〈0.05）, while the seawater control and acetone control had no significant differences. The haemocyte counts, neutral red uptake, phagocytosis and bacteriolytic activity in all B[α]P treatment groups as well as antibacterial activity in groups of 0.5, 1, 2.5 and 7.5 μgL^-1·B[α]P decreased significantly （P〈0.05）. Some of these indices tended to be stable on the sixth day and others on the ninth day, and the indices showed clear time- and concentration-response to B[α]E Bactenolytic activity in 0.1 μgL^-1 B[α]P treatment group and antibacterial activity in 0.1 ggLl and 0.5 μgL^-1 B[α]P treatment groups increased at the beginning of exposure and reached their peaks on day 1 and day 6, respectively. Following that, both activities decreased gradually and became stable after day 9. When all the indices reached stability, they were significantly lower than those in control group （P〈0.05）, except for antibacterial activity in 0.1 μgLl B[α]P treatment group （P〉0.05）. Thus, B[α]P has evident toxic effects on scallop immune system, which supports the view that a relationship exists between pollution and lmmunomodulation in aquatic organisms.

关键词： benzo[α]pyrene (B[α]P) Chlamysfarreri haemocyte counts neutral red uptake phagocytosis bacteriolytic activity antibacterial activity

Effects of Na^+/K^+ Ratio of Groundwaters on the Gill Ion-Transport Enzyme Activity,Plasma Osmolality and Growth of Cynoglossus semilaevis Juveniles

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Journal of Ocean University of China 2008年第4期7卷 447-452页

作者： YANG Huizan PAN luqing HU Fawen liu Hongyu The Key Laboratory of Mariculture Ministry of Education Ocean University of China Qingdao 266003 P. R. China

The effects of environmental Na+/K+ ratio on the gill ion-transport enzyme activity,plasma osmolality and growth of Cynoglossus semilaevis juveniles were investigated. The results showed that,plasma osmolality was similar among flounder adapted to different Na+/K+ ratios of saline groundwaters (P>0.05),while the growth,gill Na+,K+-ATPase and HCO3--ATPase activities were affected by Na+/K+ ratio significantly (P<0.05). The gill Na+,K+-ATPase activity reached its maximum on day 3,then decreased gradually from day 3 to day 9 and remained constant from day 9 to day 15. The peak values of gill Na+,K+-ATPase activity were detected on day 3 for all Na+/K+ ratios of saline groundwaters,then the enzyme activities descended,and on day 9 the enzyme activi-ties achieved steady state,and the gill HCO3--ATPase activity increased rapidly and achieved steady state after one day. During steady state,the gill Na+,K+-ATPase and HCO3--ATPase activity of Na+/K+ ratios 20 and 40 treatments were significantly higher than those in the control group (Na+/K+ ratio 27.5),while there were no significant differences between the Na+/K+ ratio 30 treatment and the control group; the gill Na+,K+-ATPase activity of Na+/K+ ratio 20 and 40 treatments were significantly higher than that for ratio 30 treatment,but there were no significant differences of gill HCO3--ATPase activity among these treatments. At the end of the 15-day experiment,the weight gain (%) and specific growth rate (SGR) of flounders maintained in seawater were significantly higher than those in groundwaters; significant differences also occurred among the treatments; Na+/K+ ratio 30 treatment had the highest values (33.7% and 1.94 respectively),which were significantly higher than those under Na+/K+ ratios 20 and 40 treatments. There-fore,for the saline groundwater used in this experiment,it is suggested that the Na+/K+ ratio be adjusted to approximately 30,i.e.,as close to that of natural seawater as possible in the culture of floun

关键词： Na^-/K^- ratio Cynoglossus semilaevi ion-transport enzyme activity plasma osmolality growth

Effects of Heavy Metal Ions (Cu^(2+), Pb^(2+) and Cd^(2+)) on DNA Damage of the Gills, Hemocytes and Hepatopancreas of Marine Crab, Charybdis japonica

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Journal of Ocean University of China 2011年第2期10卷 177-184页

作者： PAN luqing liu Na ZHANG Hongxia WANG Jing MIAO Jingjing Department of Aquiculture the Key Laboratory of Mariculture Ministry of EducationOcean University of China Qingdao 266003 P. R. China

There are rising concerns about the hazardous effects of heavy metals on the environment. In this study, comet assay and DNA alkaline unwinding assay were conducted on the tissues (gills, hepatopancreas, and hemocytes) of Charybdis japonica in order to illustrate genotoxicity of three heavy metal ions (Cu2+, Pb2+, and Cd2+) on the marine crabs C. japonica. The crabs were exposed to Cu2+ (10, 50, and 100 ?g.L?1), Pb2+ (50, 250, and 500 ?g L?1) and Cd2+ (5, 25, and 50 ?g L?1), and the tissues were sampled at days 0.5, 1, 3, 6, 9, and 15. DNA alkaline unwinding assay was used for testing the DNA single strand break in gills and hepatopancreas and comet assay was employed for testing the DNA damage in hemocytes. The results showed that the DNA damage (F-value) of gills in the crabs exposed to the three heavy metals was decreased gradually during the exposure periods and there was a dose-time response relationship in certain time, suggesting that the levels of DNA single strand break in all the experimental groups increased significantly compared to the controls. Changes of F-value in hepatopancreas of the crabs exposed to the three heavy metals were similar to those in gills except that the peak values were found in the 500 ?g L?1 Pb2+ treatment group at day 3 and the 50 ?g L?1 Cd2+ treatment group at day 9. The ranks of DNA damage in gills and hepatopancreas induced by the three heavy metal ions (50 ?g L?1, day 15) were Cd2+ >Pb2+ >Cu2+ and Pb2+ >Cu2+ >Cd2+. The levels of DNA damage in gills were higher than those in hepatopancreas in the same experimental group. It can be concluded that indices of DNA damage can be used as the potential biomarkers of heavy metal pollution in marine environment.

关键词： crabs heavy metal genotoxicity comet assay DNA alkaline unwinding assay

路用水性环氧改性乳化沥青组成优化及耐久性能评价

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材料导报 2023年第18期37卷 278-286页

作者：傅豪王朝辉刘鲁清刘伟余四新长安大学公路学院西安710064 山东高速集团有限公司济南250098 山东高速交通建设集团股份有限公司济南250101

为提升改性乳化沥青在道路领域的使用品质和耐久性,制备了多种水性环氧改性乳化沥青,基于拉伸性能优化了改性乳化沥青配比,研究了水性环氧改性乳化沥青的黏附性能、黏度、干燥时间、相容性和粘结性能,分析了水性环氧改性乳化沥青粘结性... 详细信息

为提升改性乳化沥青在道路领域的使用品质和耐久性,制备了多种水性环氧改性乳化沥青,基于拉伸性能优化了改性乳化沥青配比,研究了水性环氧改性乳化沥青的黏附性能、黏度、干燥时间、相容性和粘结性能,分析了水性环氧改性乳化沥青粘结性能与其拉伸性能、黏附性能的关联性,采用湿热老化、冻融循环和氙灯光照老化等方式模拟复杂气候条件对水性环氧改性乳化沥青的破坏作用,以经老化处理后的残留拉伸、黏附和粘结性能及处理前后各项性能的变化率作为评价指标,基于熵权的理想点法综合评价了水性环氧改性乳化沥青的耐久性能。结果表明:水性环氧树脂能够有效提升乳化沥青的拉伸强度和黏附性能,水性环氧改性乳化沥青具备较好的流动性和适宜的干燥时间,且水性环氧树脂与乳化沥青具有较好的相容性,建议水性环氧树脂掺量为15%~25%(质量分数,下同)。水性环氧改性乳化沥青的粘结性能与其力学强度和黏附性能具有较强的关联性。水性环氧改性乳化沥青经湿热老化、冻融循环或氙灯光照老化处理后拉伸、黏附和粘结等性能保持率为84%~92%,聚氨酯改性后的水性环氧改性乳化沥青表现出更好的耐久性能,聚氨酯改性双酚A型E-51水性环氧改性乳化沥青的综合耐久性能最佳。

关键词：道路材料改性乳化沥青水性环氧树脂耐久性能

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高强度织构对2524铝合金疲劳性能的影响

粉末冶金材料科学与工程 2017年第3期22卷 307-312页

作者：鲁璐青刘志义夏鹏中南大学材料科学与工程学院长沙410083

对分别含有高强度高斯织构和高强度立方织构状态的2种2524-T4铝合金板材的疲劳裂纹扩展速率和短裂纹扩展行为进行研究,用扫描电镜(SEM)观察疲劳试样断口形貌和疲劳短裂纹的扩展路径,研究织构类型对合金疲劳性能的影响。结果表明:高斯取... 详细信息

对分别含有高强度高斯织构和高强度立方织构状态的2种2524-T4铝合金板材的疲劳裂纹扩展速率和短裂纹扩展行为进行研究,用扫描电镜(SEM)观察疲劳试样断口形貌和疲劳短裂纹的扩展路径,研究织构类型对合金疲劳性能的影响。结果表明:高斯取向晶粒能够提高材料疲劳裂纹扩展的门槛值及增强疲劳裂纹的扩展抗力,使材料在更高的应力强度因子下发生失稳扩展;而高强度立方织构对疲劳性能的影响相对较小。在近门槛区,高斯晶粒通过裂纹偏转的形式有效阻碍短裂纹扩展,在稳态扩展区,高斯晶粒能明显降低疲劳裂纹的扩展速率,高斯织构还能延长合金疲劳裂纹稳态的扩展区,提高合金的疲劳损伤容限。因此,高强度高斯织构的2524-T4铝合金板材比立方织构的合金具有更好的疲劳性能。

关键词： 2524铝合金高斯织构立方织构疲劳裂纹扩展抗力疲劳损伤容限

基于改进鲸鱼优化算法的同步相量测量单元多目标优化配置

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现代电力 2024年第4期41卷 652-658页

作者：杭鲁庆刘敏贵州大学电气工程学院贵州省贵阳市550025

针对因配电网节点数目多但投资成本少造成的同步相量测量单元(phasor measurement unit,PMU)供需不平衡问题,建立了考虑PMU配置个数、状态估计误差的PMU多目标优化配置模型,优化问题的目标是最小化所需的PMU个数和最小化状态估计误差。... 详细信息

针对因配电网节点数目多但投资成本少造成的同步相量测量单元(phasor measurement unit,PMU)供需不平衡问题,建立了考虑PMU配置个数、状态估计误差的PMU多目标优化配置模型,优化问题的目标是最小化所需的PMU个数和最小化状态估计误差。并提出一种改进鲸鱼优化算法来求解模型。首先引入非支配排序和拥挤度计算来选择并排序Pareto非支配解,保证算法求解全局最优值的能力,其次引入Levy飞行策略对鲸鱼优化算法的螺旋更新位置进行变异扰动,使算法不易陷入局部最优。最后,采用优化配置模型对IEEE 33标准节点系统进行仿真计算。结果表明,与遗传算法和粒子群算法相比,采用改进鲸鱼优化算法求解PMU多目标优化配置模型具有更高的可行性和有效性。

关键词：配电网相量测量单元多目标优化配置状态估计 Pareto最优解改进鲸鱼优化算法

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深化教学改革搞好农业继续教育

中国农业教育 2002年第1期3卷 20-21页

作者：刘鲁庆山东省农业管理干部学院山东济南250100

深化教学改革,提高教育质量,是发展农业继续教育至关重要的问题,本文从四个方面阐述了对策。

关键词：农业继续教育教学改革教学质量教学内容竞争机制教学质量制度建设

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路用水性环氧树脂的拉伸强度预测和极值寻优

材料导报 2021年第16期35卷 16172-16177页

作者：陈谦王朝辉傅豪樊振通刘鲁清长安大学公路学院西安710064

为实现路用水性环氧树脂力学参数极值寻优,以进一步科学优化其材料组成及配比,基于不同类型原材料自身属性及其掺量的调控,制备了一系列路用水性环氧树脂;以拉伸强度为例,开展了力学参数标定试验并获取了75组有效数据,以此构建了基于小... 详细信息

为实现路用水性环氧树脂力学参数极值寻优,以进一步科学优化其材料组成及配比,基于不同类型原材料自身属性及其掺量的调控,制备了一系列路用水性环氧树脂;以拉伸强度为例,开展了力学参数标定试验并获取了75组有效数据,以此构建了基于小样本数据的传统多元回归方程、典型前馈式及反馈式神经网络等不同预测模型,对比分析了不同模型的拟合效果与预测精度;采用遗传算法对优选的预测模型进行优化,实现了拉伸强度极值寻优功效,回溯确定了原材料各项属性及掺量的最佳取值,为路用水性环氧树脂材料组成及配比的科学优化提供有益借鉴。结果表明:相比五元非线性回归方程和反向传播(Back Propagation,BP)模型,Elman模型的预测误差降低了25.94%~37.5%,具有较好的预测精度和稳定性;综合考虑预测精度和运算速度,推荐采用Elman神经网络(6×4×1)作为路用水性环氧树脂拉伸强度的预测模型;采用遗传算法可快速获得最优拉伸强度和相关材料组成及配比,降低试验成本,但其准确度仍需进一步优化。

关键词：道路材料水性环氧树脂力学参数拉伸强度小样本极值寻优