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二氢槲皮素和β-烟酰胺单核苷酸顺势和逆势给药对健康大鼠生长和生理的影响

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吉林医学 2024年第8期45卷 1783-1788页

作者：甘永金梁丹玉陈瑞泽蓝保强蒋盛军广西壮族自治区职业病防治研究院职业卫生与毒性评价所广西南宁530021 广西壮族自治区中医药研究院制剂中心广西壮族自治区中药质量标准研究重点实验室

目的:通过研究二氢槲皮素和β-烟酰胺单核苷酸顺势和逆势给药对健康大鼠生长和生理的影响,进一步验证中医阴阳分药分时服用方剂学理论。方法:48只无特定病原体级SD大鼠,随机分为顺势饲喂组、逆势饲喂组、混合饲喂组、对照组各12只,雌雄... 详细信息

目的:通过研究二氢槲皮素和β-烟酰胺单核苷酸顺势和逆势给药对健康大鼠生长和生理的影响,进一步验证中医阴阳分药分时服用方剂学理论。方法:48只无特定病原体级SD大鼠,随机分为顺势饲喂组、逆势饲喂组、混合饲喂组、对照组各12只,雌雄各半,顺势饲喂组早晨给予二氢槲皮素溶液,下午给予β-烟酰胺单核苷酸溶液,逆势饲喂组给药顺序与顺势饲喂组相反,混合饲喂组给予二氢槲皮素和β-烟酰胺单核苷酸混合溶液灌胃,分早晚两次给药,对照组早晚给予灌胃等量超纯水,四组均每周给药5 d,共给药6周。分别于饲喂第1天、第10天、第20天、第30天、第45天时观察各组大鼠的皮肤毛发、行为状态、兴奋程度、激怒反应、睡眠状态、大便状态。分别于饲喂后第2周、第4周、第6周的周一、周三、周五测定大鼠采食量和体重,饲喂第45天检测大鼠的血液常规和血生化指标,计算脏器系数。结果:实验期间,各组大鼠的皮肤毛发、行为状态、兴奋程度、激怒反应、睡眠状态、大便状态均未见明显改变。四组雌、雄性大鼠在各个阶段的日均采食量和体重比较差异均无统计学意义(P>0.05)。给药6周后,四组大鼠肝、脾、肺、肾、胃脏器系数、白细胞计数、中性粒细胞计数、淋巴细胞计数、单核细胞计数、嗜酸性粒细胞计数、红细胞计数、血红蛋白、血清总蛋白、总胆红素、碱性磷酸酶、三酰甘油、血清总胆固醇、尿素、空腹血糖、肌酐、钾离子比较,差异均无统计学意义(P>0.05)。雄性大鼠顺势饲喂组和逆势饲喂组心脏脏器系数低于对照组(P<0.05);雌性大鼠顺势饲喂组谷丙转氨酶高于对照组(P<0.05);雄性大鼠混合饲喂组谷草转氨酶高于对照组(P<0.05);雌性大鼠混合饲喂组钠离子低于对照组,差异均有统计学意义(P<0.05)。结论:顺势给药和逆势给药可引起大鼠心脏脏器系数降低,混合给药可引起大鼠谷草转氨酶增高,钠离子降低。

关键词：阴阳五行方剂学二氢槲皮素 β-烟酰胺单核苷酸顺势给药逆势给药

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发动机工作状态对排气扩压器流动特性的影响

西南科技大学学报 2024年第2期39卷 92-99页

作者：王韬竣张健平但志宏张松李浩东伍相全西南科技大学制造科学与工程学院四川绵阳621010 中国航空发动机集团有限公司四川燃气涡轮研究院四川绵阳621703

为了准确描述发动机工作状态对高空台排气扩压器流动特性的影响,采用Fluent软件数值模拟分析了3 km和5 km飞行高度,发动机中间状态、小加力状态和最大状态下高空台排气扩压器气流压力、速度、温度的变化规律。结果表明:飞行高度为3 km和... 详细信息

为了准确描述发动机工作状态对高空台排气扩压器流动特性的影响,采用Fluent软件数值模拟分析了3 km和5 km飞行高度,发动机中间状态、小加力状态和最大状态下高空台排气扩压器气流压力、速度、温度的变化规律。结果表明:飞行高度为3 km和5 km时,相同状态下排气扩压器内气流压力、速度、温度变化趋势基本一致。经过排气扩压器扩压减速后,发动机中间状态、小加力状态和最大状态下气流静压增加了12%,21%,25%,气流速度衰减了79%,80%,76%。当发动机工作状态从中间状态转变为最大状态时,排气扩压器内气流温度逐渐升高,波动也越大。

关键词：发动机工作状态排气扩压器流动特性数值模拟分析

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复杂道路环境下大流量路口多车牌自动识别

计算机仿真 2024年第8期41卷 150-154,160页

作者：张晓辉宋欧铭郑维于心俊河南工业大学电气工程学院河南郑州450001

复杂道路口车流量大,车牌采集图像存在遮挡,倾斜等现象,导致车牌检测准确率低、泛化性差。为解决上述问题,提出一种基于改进Yolov3车辆识别与Mask R-CNN车牌检测相融合的算法,通过两步分别检测车辆与车牌,最终构建出YOL3-RCNN多车牌识... 详细信息

复杂道路口车流量大,车牌采集图像存在遮挡,倾斜等现象,导致车牌检测准确率低、泛化性差。为解决上述问题,提出一种基于改进Yolov3车辆识别与Mask R-CNN车牌检测相融合的算法,通过两步分别检测车辆与车牌,最终构建出YOL3-RCNN多车牌识别模型。模型首先基于上采样算法将图像的大、中、小特征有机融合;然后采用形态聚类算法,自适应计算IOU阈值,提高车辆检出率与准确率;接着对检测出的车辆进行裁剪,SOFTNMS优化与仿射变换,解决车牌遮挡,倾斜与背景复杂的难题;最后基于ResNet50网络识别车牌字符与数字,并利用RPN进行回归校验。多组基线算法的仿真结果显示,在UA-DETRAC车辆检测数据集上,与传统车牌检测算法相比,YOL3-RCNN算法的准确率与召回率分别提高了7.7%与9.6%,且具有较高的车牌检测速率。综上所述,所构建的YOL3-RCNN多车牌识别模型具有较高的检测准确性、时效性与普适性。

关键词：复杂道路环境大流量路口多车牌自动识别

Effect of tunnel structure on the specific capacitance of etched aluminum foil

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International Journal of Minerals,Metallurgy and Materials 2014年第10期21卷 974-979页

作者： Ning Peng Li-Bo Liang Ye-Dong He Hong-Zhou song Xiao-Fei Yang Xiao-yu Cai Beijing Key Laboratory for Corrosion Erosion and Surface Technology University of Science and Technology Beijing Institute of Technology Research and Development of Electronic Aluminum Foil Guangxi Hezhou Guidong Electronics Technology Co. Ltd.

The morphology of etched aluminum foil was observed using scanning electron microscopy, which led to the establishment of a cylindrical model and two merged models, considering the fixed weight loss of etching. The maximum of specific capacitance and the cor- responding optimum values for tunnel sizes at various anodization voltages were predicted. The increased size distribution and taper of tun- nels were demonstrated to decrease the specific capacitance, whereas the addition of polymeric additive into the ttmnel widening solution was demonstrated to increase the capacitance. The formation of merged tunnels on the etched aluminum surface, irrespective of the presence of row-merged tunnels or cluster-merged tunnels, resulted in a dramatic decrease in the specific capacitance. It is concluded that, enhancing the uniformity of turmel size and distribution and avoiding the formation of merged tunnels are the effective approach to achieving the higher capacitance for the tunnel etched and formed aluminum foil.

关键词： aluminum foil pitting corrosion capacitance morphology electrolytic capacitors

Silica nanoparticle with a single His-tag for addressable functionalization, reversible assembly, and recycling

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Nano Research 2018年第5期11卷 2512-2522页

作者： yuye Cao Yangdong Cui yu Yang Jie Hua Zheng-Mei song Haifang Wang yuanfang Liu Aoneng Cao Institute of Nanochemistry and Nanobiology Shanghai University Shanghai 200444 China Beijing National Laboratory for Molecular Sciences College of Chemistry and Molecular Engineering Peking University Beijing 100871 China

For many biomedical and catalytic applications, such as encapsulation of proteins/enzymes in nanopartides （NPs）, it is preferable to have well-dispersed small NPs that are stable in solution and behave quasi-homogeneously. However, conventional liquid phase methods for small-NP synthesis and functionalization usually face great difficulties in separation/purification and recycling. In addition, controlling the orientation of proteins inside NPs is also a crucial issue to maximize the activity of the encapsulated proteins. Herein, we report a solid phase method to solve these problems. Using His-tagged proteins as cores, well-dispersed core-sheU silica NPs are facilely synthesized and functionalized in a column. The core His-tagged proteins are kept bound on the surface of the resIn beads in the column during the entire process, making the separation/purification of NPs and their precursors during the multiple-step process as simple as a few-minutes procedure of draining and washing the column. Each obtained silica NP has an adjustable eccentric core-shell structure with only one His-tag sticking out of the particle. This single His-tag on the surface of each NP not only makes it easy for addressable and stoichiometric functionalization of the NP but also provides an easy way to reversibly assemble NPs into dimers or be oriented on the surface of large particles. Notably, this solid phase approach also provides a versatile means to control the orientation of proteins inside NPs, and the His-tag makes it easy to recycle those well-dispersed small NPs.

关键词： His-tagged nanoparticle solid phase reversible assembly addressable functionalization protein orientation

Monitoring biofouling based on aerobic respiration in reverse osmosis system

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Journal of Environmental Sciences 2019年第4期31卷 247-256页

作者： Youngjae yu Keun-Young Park Jaehyun Jung Wonjung song Jaehyeok Kim Junhee Ryu Harshad Lade Jihyang Kweon Department of Environmental Engineering Konkuk University Department of Environment and Energy Sejong University Department of Laboratory Medicine Hallym University Medical Center

A monitoring method of biofouling in reverse osmosis(RO) system was proposed based on the fluorescent signal of resorufin, which is reduced by nicotinamide adenine dinucleotide released from viable cells during aerobic respiration. The fluorescent signal of resorufin reduced by planktonic cells and microorganisms of biofilm showed linearity, indicating its feasibility to monitor biofouling in a RO system. For the application of the method to the lab-scale RO system, the injection concentration of resazurin and the injection flow rate were optimized. Biofilm on RO membranes continuously operated in a lab-scale RO system was estimated by resorufin fluorescence under optimized detection condition. As a result,resorufin fluorescence on RO membrane showed a significant increase in which the permeability of RO system decreased by 30.48%. Moreover, it represented the development of biofilm as much as conventional biofilm parameters such as adenosine triphosphate,extracellular polymeric substances, and biofilm thickness. The proposed method could be used as a sensitive and low-cost technology to monitor biofouling without autopsy of membranes.

关键词： On-site monitoring Biofilm Aerobic respiration Resazurin reduction mechanism Resorufin fluorescence

Determination of lisinopril using anion exchange chromatography with integrated pulsed amperometric detection

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Chinese Chemical Letters 2012年第3期23卷 335-338页

作者： yu Xiu Liu dan Shou Mei Lan Chen Zhi Dong Chen Pei Min Zhang Yan Zhu School of Chemistry and Chemical Engineering Changzhou UniversityChangzhou 213164China Zhe Jiang Academy of Traditional Chinese Medicine Hangzhou 310007China College of Biology and Environment Engineering Zhejiang Shuren UniversityHangzhou 310015China Department of Chemistry Xixi CampusZhejiang UniversityHangzhou 310028China

A rapid and practical method for direct detection of lisinopril in anion exchange chromatography（AEC） has been developed with integrated pulsed amperometric detection（IPAD）.Dionex AS 18（250 mm×2 mm） and AG 18（50 mm×2 mm） columns and 40 mmol/L NaOH solution were used for ***-step potential waveform parameters were optimized to maximize the signal-to-noise ratio（S/N）.Utilizing the optimized waveform,the repeatability（intra-day） precision and intermediate（inter-day） precision were obtained with relative standard deviation（RSD） of 0.74,0.93,*** limit of quantification（LOQ） and limit of detection（LOD） were found to be 0.37,0.12ng/mL,respectively,with the correlation coefficient of 0.9998 over concentration range 0.01-1μg/*** present method was successfully applied to the determination of lisinopril in human *** recoveries of plasma sample spiked by 0.2μg/mL,0.8μg/mL lisinopril were 98.31-103.23%with RSD of 1.41%, 0.61%,respectively.

关键词： Lisinopril Integrated pulsed amperometry Anion exchange chromatography Angiotensin converting enzyme inhibitor Plasma

Preliminary study on different nutrient pools supplies for the phytoplankton growth in the Jiaozhou Bay in China in the fall of 2004

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Acta Oceanologica Sinica 2007年第3期26卷 110-120页

作者： WANG dan SUN Jun song Shuqun LUAN Qingshan Joey McMurdie Key Laboratory of Marine Ecology ＆ Environmental Science Institute of Oceanology Chinese Academy of Sciences Qingdao 266071 China Depatment of Civil ＆ Environmental Engineering Stanford University California 94305 USA

The source and significance of two nutrients, nitrogen and phosphorous, were investigated by a modified dilution method performed on seawater samples from the Jiaozhou Bay, in autumn 2004. This modified dilution method accounted for the phytoplankton growth rate, microzooplankton grazing mortality rate, the internal and external nutrient pools, as well as nutrient supplied through remineralization by microzooplankton. The results indicated that the phytoplankton net growth rate increased in turn from inside the bay, to outside the bay, to in the Xiaogang Harbor. The phytoplankton maximum growth rates and microzooplankton grazing mortality rates were 1.14 and 0.92 d^-1 outside the bay, 0.42 and 0.32 d^ -1 inside the bay and 0.98 and 0.62 d^-1 in the harbor respectively. Outside the bay, the remineralized nitrogen （Kt = 24.49） had heavy influence on the growth of the phytoplankton. Inside the bay, the remineralized phosphorus（Kt = 3.49） strongly affected the phytoplankton growth. In the harbor, the remineralized phosphorus （Kt = 3.73） was in larger demand by phytoplankton growth. The results demonstrated that the dif- ferent nutrients pools supplied for phytoplankton growth were greatly in accordance with the phytoplankton community structure, microzooplankton grazing mortality rates and environmental conditions. It is revealed that nutrient remineralization is much more important for the phytoplankton growth in the Jiaozhou Bay than previously believed.

关键词： phytoplankton external nutrient internal nutrient remineralized nutrient maximum growth rate microzooplankton grazing mortality rate Jiaozhou Bay

Hydrogen-bonded Intramolecular Charge Transfer Excited State of Dimethylaminobenzophenone using Time Dependent Density Functional Theory

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Chinese Journal of Chemical Physics 2012年第6期25卷 654-658,I0003页

作者： yu-ling Chu Zhong Yang Zhe-feng Pan Jing Liu yue-yi Han Yong Ding Peng song Physical and Electronic and Information Engineering Institute Chifeng University Chifeng 024001China Department of Physics Liaoning University Shenyang 110036 China Department of Science Shenyang Aerospace University Shenyang 110136 China

Density functional theory and time-dependent density-functional theory have been used to investigate the photophysical properties and relaxation dynamics of dimethylaminobenzophe- none （DMABP） and its hydrogen-bonded DMABP-MeOH dimer. It is found that, in non- polar aprotic solvent, the transitions from So to S1 and S2 states of DMABP have both n→π and π→π＊ characters, with the locally excited feature mainly located on the C=O group and the partial CT one characterized by electron transfer mainly from the dimethylaminophenyl group to the C=O group. But when the intermolecular hydrogen bond C=O…H-O is formed, the highly polar intramolecular charge transfer character switches over to the first excited state of DMABP-MeOH dimer and the energy difference between the two low- lying electronically excited states increases. To gain insight into the relaxation dynamics of DMABP and DMABP-MeOH dimer in the excited state, the potential energy curves for con- formational relaxation are calculated. The formation of twisted intramolecular charge trans- fer state via diffusive twisting motion of the dimethylamino/dimethylaminophenyl groups is found to be the major relaxation process. In addition, the decay of the Si state of DMABP-MeOH dimer to the ground state, through nonradiative intermolecular hydrogen bond stretching vibrations, is facilitated by the formation of the hydrogen bond between DMABP and alcohols.

关键词： Hydrogen-bond Intramolecular charge transfer Relaxation dynamic Twistingdynamic