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Journal of Wuhan University of Technology(Materials Science) 2018年第4期33卷 1007-1013页

作者：齐晓丹 jia xile 宋益民 Department of Pharmaceutical Engineering Qingdao University of Science&TechnologyQingdao 266042China E E-jiao Co. Ltd.Liaocheng 252200China

Amphiphilic CS-SA polymers were prepared using the SA modified by small molecule water-soluble chitosan, and CS-SA nanomicelles and FF/CS-SA nanomicelles were prepared by using CSSA polymers as the material with dialysis-ultrasound method. CS-SA polymers, CS-SA nanomicelles, and FF/CS-SA nanomicelles were characterized by FT-IR, TGA, and SEM. Results showed that the SA was grafted to the amino of CS by amide bond. CS-SA nanomicelles and FF/CS-SA nanomicelles were spherical, smooth without fold. The influence of different molar ratio of FF to CS-SA polymers on the encapsulation efficiency and drug-loading rate determined the best molar ratio that was 1：1.09. In vitro release experiments, drug release performance study found that hydrophobic drug releasing from FF/CS-SA nanomicelles presented sustainedrelease. In vitro bacteriostasis experiments, when the concentration was higher than 4.98 mg/mL, FF/CSSA nanomicelles had antibacterial action and a positive correlation with concentration. The results revealed that amphiphilic chitosan derivative nanomicelles were carriers with broad prospects, increasing solubility of hydrophobic drugs and presenting sustained release for hydrophobic drugs, which provided a new research idea for drug delivery and targeted drug delivery of hydrohobic drugs.

关键词： nanomicelle water-soluble chitosan hydrophobic drug antibacterial activity

Right ventricular-arterial uncoupling as an independent prognostic factor in acute heart failure with preserved ejection fraction accompanied with coronary artery disease

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Chinese Medical Journal 2023年第10期136卷 1198-1206页

作者： Hongdan jia Li Liu xile Bi Ximing Li Hongliang Cong Department of Cardiology Clinical School of ThoracicTianjin Medical UniversityTianjin 300222China Department of Cardiology The First Hospital of QinhuangdaoQinhuangdaoHebei 066000China

Background:Right ventricular(RV)-arterial uncoupling is a powerful independent predictor of prognosis in heart failure with preserved ejection fraction(HFpEF).Coronary artery disease(CAD)can contribute to the pathophysiological characteristics of *** study aimed to evaluate the prognostic value of RV-arterial uncoupling in acute HFpEF patients with ***:This prospective study included 250 consecutive acute HFpEF patients with *** were divided into RV-arterial uncoupling and coupling groups by the optimal cutoff value,based on a receiver operating characteristic curve of tricuspid annular plane systolic excursion to pulmonary artery systolic pressure(TAPSE/PASP).The primary endpoint was a composite of all-cause death,recurrent ischemic events,and HF ***:TAPSE/PASP≤0.43 provided good accuracy in identifying patients with RV-arterial uncoupling(area under the curve,0.731;sensitivity,61.4%;and specificity,76.6%).Of the 250 patients,150 and 100 patients could be grouped into the RV-arterial coupling(TAPSE/PASP>0.43)and uncoupling(TAPSE/PASP≤0.43)groups,*** strategies were slightly different between groups;the RV-arterial uncoupling group had a lower rate of complete revascularization(37.0%[37/100]vs.52.7%[79/150],P*** Cox analysis showed TAPSE/PASP≤0.43 as an independent associated factor for the primary endpoint,all-cause death,and recurrent HF hospitalization(hazard ratios[HR]:2.21,95%confidence interval[CI]:1.44-3.39,P<0.001;HR:3.32,95%CI:1.30-8.47,P=0.012;and HR:1.93,95%CI:1.10-3.37,P=0.021,respectively),but not for recurrent ischemic events(HR:1.48,95%CI:0.75-2.90,P=0.257).Conclusion:RV-arterial uncoupling,based on TAPSE/PASP,is independently associated with

关键词： Heart failure with preserved ejection fraction Coronary artery disease Right ventricular-arterial coupling Prognosis Revascularization

Effect of Hybrid Synapses on Vibrational Resonance in Neuron Populations with Small-world Topology

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Effect of Hybrid Synapses on Vibrational Resonance in Neuron...

第24届中国控制与决策会议

作者： jianbing Sun, Bin Deng, xile Wei, jiang Wang, jia Zhao School of Electrical Engineering and Automation, Tianjin University, Tianjin 300072, China

The response of fifty coupled FitzHugh-Nagumo neurons with small-world topology, under high-frequency driving, to a subthreshold signal is investigated. We demonstrate the occurrence of vibrational resonance and it is shown that optimal amplitude of the high-frequency driving enhances the response of neuron populations to a subthreshold low-frequency input. Simulation results show that chemical coupling is more efficient than electrical coupling in signal detection and electrical coupling is better in signal transmission for local input. Networks with hybrid synaptic couplings combine the advantages in signal detection and propagation. By altering the ratio of the two types of synapse in hybrid coupled neuron population, it is shown that no matter what its ratio in a neuron population is, the chemical synapses will improve the ability of weak signal detection of neuron populations all the time. And the larger ratio of the electrical coupling in a neuron population is, the better the signal is propagated.

关键词： Vibrational Resonance Hybrid Synapses Small-world Network

Dynamical Encoding of Winnerless Competition Network induced by Vibrational Resonance

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Dynamical Encoding of Winnerless Competition Network induced...

第24届中国控制与决策会议

作者： jia Zhao, Bin Deng, xile Wei, jiang Wang, jianbing Sun School of Electrical Engineering and Automation, Tianjin University, Tianjin 300072, China

In this paper, a winnerless competition（WLC） network consists of nine FitzHugh-Nagumo（FHN） neurons have been introduced to investigate the effect of high-frequency driving on the response of neuron system to a subthreshold low-frequency signal. We show that optimal amplitude of high-frequency driving enhances the response of neuron system to a subthreshold low-frequency input. Further, we also show that vibrational resonance（VR） in the WLC network can also induce the system to produce the spatiotemporal encoding. We find that it can efficiently improve the spatiotemporal encoding of the WLC network in response to subthreshold low-frequency input.

关键词： vibrational resonance winnerless competition network

近红外漫反射光谱法快速测定首乌丸中二苯乙烯苷的含量

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中国药房 2017年第18期28卷 2539-2542页

作者：刘喜乐贾灿潮姬生国广东药科大学中药学院广州510006

目的:建立快速测定首乌丸中二苯乙烯苷含量的方法。方法:采用高效液相色谱法(HPLC)测定首乌丸中二苯乙烯苷的含量(作为实测值):色谱柱为ODS-C_18,流动相为乙腈-水(25∶75,V/V),流速为0.8 m L/min,检测波长为320 nm,柱温为30℃,进样量为1... 详细信息

目的:建立快速测定首乌丸中二苯乙烯苷含量的方法。方法:采用高效液相色谱法(HPLC)测定首乌丸中二苯乙烯苷的含量(作为实测值):色谱柱为ODS-C_18,流动相为乙腈-水(25∶75,V/V),流速为0.8 m L/min,检测波长为320 nm,柱温为30℃,进样量为10μL。采用偏最小二乘法-近红外漫反射光谱法建立预测首乌丸中二苯乙烯苷含量的定量校正模型:根据实测值,采集校正集样品76份、验证集样品18份,以标准归一化法、一阶导数法联合滤波法预处理光谱,最佳波段为9 000~4 150 cm^(-1),主成分因子数为12。结果:首乌丸中二苯乙烯苷的含量测定方法学考察符合要求。二苯乙烯苷含量预测的定量校正模型内部交叉验证决定系数为0.991 90,校正均方根偏差为0.020 1,预测均方根偏差为0.023 6,交叉验证均方根偏差为0.076 29,预测值与实测值差异无统计学意义(P>0.05)。结论:该方法准确、稳定、简便,可用于首乌丸中二苯乙烯苷含量的快速测定。

关键词：近红外漫反射光谱法首乌丸二苯乙烯苷含量偏最小二乘法

The effects of external electrical field on a neural network with synaptic plasticity and conduction delays

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The effects of external electrical field on a neural network...

第24届中国控制与决策会议

作者： jia Zhao, Bin Deng, xile Wei, jiang Wang, Cong Men, Yingmei Qin, jianbing Sun School of Electrical Engineering and Automation, Tianjin University, Tianjin, 300072, China

Effects of external DC stimuli to the evolution of a neural network model are studied. It’s found that the external DC stimuli can enhance the neural network’s average firing rate, induces the neural network to get to a balanced state that exhibits rhythmic activity with high rate. The activity of the neural network can be affected by the synaptic connection strength, the conduction delays, the external stimuli and so on. These parameters can serve as factors in modulating the evolution of the neural network with different firing activities. Furthermore, these results may also relate to the mechanism of memory and learning process.

关键词： Spike-timing-dependent plasticity (STDP) Weak direct current stimuli Rhythmic activity

二氯喹啉草酮在水稻植株上的消解动态及其在稻秆、稻谷和土壤中的最终残留

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农药学学报 2020年第2期22卷 388-396页

作者：周勇邓希乐马海昊朱航刘佳周小毛柏连阳湖南省农业科学院湖南省农业生物技术研究所长沙410125

二氯喹啉草酮是经中国农业农村部批准登记的茎叶处理除草剂,迄今为止对其潜在的环境污染尚未见报道。本研究建立了一种采用QuEChERS前处理方法结合高效液相色谱-串联三重四极杆质谱(HPLC-MS/MS)联用技术检测二氯喹啉草酮在水稻植株、稻... 详细信息

二氯喹啉草酮是经中国农业农村部批准登记的茎叶处理除草剂,迄今为止对其潜在的环境污染尚未见报道。本研究建立了一种采用QuEChERS前处理方法结合高效液相色谱-串联三重四极杆质谱(HPLC-MS/MS)联用技术检测二氯喹啉草酮在水稻植株、稻谷和土壤中残留的方法,并采用该方法测定了二氯喹啉草酮在水稻植株中的消解动态和最终残留。结果表明:二氯喹啉草酮的进样质量浓度与其峰面积间呈良好的线性相关,R2>0.99;其在植株、土壤、田水、稻壳和糙米中的平均回收率在78%~99%之间,相对标准偏差(RSD)在3.9%~11%之间,在植株、土壤、田水、稻壳和糙米中的最低检测浓度(LOQ)均为0.002 mg/kg。二氯喹啉草酮在水稻植株中的消解半衰期为6.7~12.8 d。以有效成分900~1350 g/hm2的剂量于水稻苗期施用1次,在施药96 d后采集的土壤、稻壳和糙米中均未检测出二氯喹啉草酮。本研究结果可为水稻中二氯喹啉草酮最大残留限量值和田间使用规范的制定提供参考。

关键词：高效液相色谱-串联三重四极杆质谱消解动态二氯喹啉草酮水稻植株土壤残留

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航空发动机用W形金属封严环结构优化设计

润滑与密封 2019年第3期44卷 12-16页

作者：李伟平王立功贾占举单喜乐湖南大学机械与运载工程学院湖南长沙410082

为提高航空发动机W形金属封严环的密封性能,以某W形金属封严环为研究对象,建立金属封严环二维轴对称有限元模型,通过轴向刚度仿真与试验验证了仿真模型的正确性。利用ANSYS软件APDL语言和参数化技术对金属封严环结构尺寸进行参数化建模... 详细信息

为提高航空发动机W形金属封严环的密封性能,以某W形金属封严环为研究对象,建立金属封严环二维轴对称有限元模型,通过轴向刚度仿真与试验验证了仿真模型的正确性。利用ANSYS软件APDL语言和参数化技术对金属封严环结构尺寸进行参数化建模,以增大封严环与法兰间的接触应力为目标,利用ANSYS零阶优化算法对金属封严环进行结构参数优化,得到了其最优截面尺寸。结果表明:优化后W形金属封严环壁厚和波高有所减小,而最大接触应力提高了8.8%,最大Von-Mises应力降低了4.3%,因而可提升金属封严环密封性能和使用寿命;优化后W形金属封严环轴向刚度仅降低3.2%,对其力学性能影响不大。

关键词： W形金属封严环航空发动机接触应力优化设计

Complete Synchronization in the Globally Delay-Coupled Hindmarsh-Rose Large-scale Network

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Complete Synchronization in the Globally Delay-Coupled Hindm...

第三十届中国控制会议

作者： jia Chenhui~1,WANG jiang~1,WEI xile~1,DENG Bin~1,CHE Yanqiu~2 1.School of Electrical and Automation Eng.,Tianjin University,300072,Tianjin,P.R.China 2.School of Automation and Electrical Engineering,Tianjin University of Technology and Education,300222, Tianjin,P.R.China

＜正＞Synchronization is a common phenomenon in coupled systems of the world,especially in complex networks combined with nonlinear *** real world,a problem of signal transfer which is unavoidable is delays in the *** this paper,we studied the complete synchronization of the globally delay-coupled Hindmarsh-Rose network with a large *** the simulations and calculations,we found that although the delay in the gap junction may desynchronize two coupled Hindmarsh-Rose oscillators,it can reduce the demand of synchronization in a large scale *** the simulation results,we guess the elimination of chaos in the network might be the reason why the delay can enhance the ability of synchronization in large-scale *** defined a quantitative indicator called period error to prove our presumption,and indicate that the proper period of delay which can synchronize a large scale network don’t have many relationship with the scale of the network when the coupling strength is in inverse proportion to the scale of the network.

关键词： Complete synchronization Time delay Large-scale network H-R model Period error

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无标度生物神经元网络的相干共振分析

动力学与控制学报 2011年第2期9卷 182-187页

作者：于海涛王江贾洪军邓斌魏熙乐天津大学电气与自动化工程学院

本文以神经元二维映射模型为节点,构造了一个具有无标度连接特性的生物神经元网络.用高斯白噪声模拟生物神经系统中的环境噪声,通过数字仿真研究了噪声对神经网络动力学行为的影响.噪声可以提高神经元的兴奋性,诱导神经元产生峰电位,当... 详细信息

本文以神经元二维映射模型为节点,构造了一个具有无标度连接特性的生物神经元网络.用高斯白噪声模拟生物神经系统中的环境噪声,通过数字仿真研究了噪声对神经网络动力学行为的影响.噪声可以提高神经元的兴奋性,诱导神经元产生峰电位,当噪声强度为某一适当值时,峰电位序列的有序度可以达到最佳,从而产生相干共振现象.另外,研究表明无标度神经网络的结构和参数变化对其共振特性有重要影响.

关键词：无标度网络神经元映射模型高斯白噪声相干共振