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Intensity and composition-dependent sign reversal of non-linearity in TiO_2/CeO_2 nanocomposites
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作者 S.Divya V.P.N.Nampoori +1 位作者 P.Radhakrishnan A.Mujeeb 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第3期298-302,共5页
CeO2/TiO2 composite nanoparticles with different Ce/Ti molar ratios have been successfully synthesized via sol-gel method. It was found that the band gap of the nanocomposite is tunable by varying Ce/Ti content. The n... CeO2/TiO2 composite nanoparticles with different Ce/Ti molar ratios have been successfully synthesized via sol-gel method. It was found that the band gap of the nanocomposite is tunable by varying Ce/Ti content. The nonlinear response of the sample was studied by using the nanosecond laser pulses from a Q switched Nd:Yag laser employing the Z-scan method. Open aperture Z-scan experiment revealed that with the increase in the CeO2 amount in the nanocomposite, the non-linearity of the composite increases, and it was assumed that this could be due to the modification of TiO2 dipole symmetry by the addition of CeO2. Closed aperture Z-scan experiment showed that when the CeO2 amount increases, positive nonlinear refraction decreases, and this could be attributed to the increase in the two photon absorption which subsequently suppresses the nonlinear refraction. 展开更多
关键词 sol-gel method non-linearity Z-scan experiment reversesaturation absorption curve
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Non-linearity Analysis of Ship Roll Gyro-stabilizer Control System
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作者 Sathit P. Chatchapol C. Phansak I. 《Sustainable Marine Structures》 2021年第1期8-21,共14页
A gyro-stabilizer is the interesting system that it can apply to marine vessels for diminishes roll motion.Today it has potentially light weight with no hy­drodynamics drag and effective at zero forward speed.The... A gyro-stabilizer is the interesting system that it can apply to marine vessels for diminishes roll motion.Today it has potentially light weight with no hy­drodynamics drag and effective at zero forward speed.The twin-gyroscope was chosen.Almost,the modelling for designing the system use linear model that it might not comprehensive mission requirement such as high sea condition.The non-linearity analysis was proved by comparison the re­sults between linear and non-linear model of gyro-stabilizer throughout fre­quency domain also same wave input,constrains and limitations.Moreover,they were cross checked by simulating in time domain.The comparison of interested of linear and non-linear close loop model in frequency domain has demonstrated the similar characteristics but gave different values at same frequency obviously.The results were confirmed again by simulation in irregular beam sea on time domain and they demonstrate the difference of behavior of both systems while the gyro-stabilizers are switching on and off.From the resulting analysis,the non-linear gyro-stabilizer model gives more real results that correspond to more accuracy in a designing gyro-sta­bilizer control system for various amplitudes and frequencies operating condition especially high sea condition. 展开更多
关键词 Active gyro-stabilizer Twin gyro-stabilizer Ship large roll motion System identification Inverse problems non-linear damping moment non-linear restoring moment
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Prediction of the undrained shear strength of remolded soil with non-linear regression,fuzzy logic,and artificial neural network
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作者 YÜNKÜL Kaan KARAÇOR Fatih +1 位作者 GÜRBÜZ Ayhan BUDAK TahsinÖmür 《Journal of Mountain Science》 SCIE CSCD 2024年第9期3108-3122,共15页
This study aims to predict the undrained shear strength of remolded soil samples using non-linear regression analyses,fuzzy logic,and artificial neural network modeling.A total of 1306 undrained shear strength results... This study aims to predict the undrained shear strength of remolded soil samples using non-linear regression analyses,fuzzy logic,and artificial neural network modeling.A total of 1306 undrained shear strength results from 230 different remolded soil test settings reported in 21 publications were collected,utilizing six different measurement devices.Although water content,plastic limit,and liquid limit were used as input parameters for fuzzy logic and artificial neural network modeling,liquidity index or water content ratio was considered as an input parameter for non-linear regression analyses.In non-linear regression analyses,12 different regression equations were derived for the prediction of undrained shear strength of remolded soil.Feed-Forward backpropagation and the TANSIG transfer function were used for artificial neural network modeling,while the Mamdani inference system was preferred with trapezoidal and triangular membership functions for fuzzy logic modeling.The experimental results of 914 tests were used for training of the artificial neural network models,196 for validation and 196 for testing.It was observed that the accuracy of the artificial neural network and fuzzy logic modeling was higher than that of the non-linear regression analyses.Furthermore,a simple and reliable regression equation was proposed for assessments of undrained shear strength values with higher coefficients of determination. 展开更多
关键词 Undrained shear strength Liquidity index Water content ratio non-linear regression Artificial neural networks Fuzzy logic
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The ridgelet transform with non-linear threshold for seismic noise attenuation in marine carbonates 被引量:5
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作者 张恒磊 宋双 刘天佑 《Applied Geophysics》 SCIE CSCD 2007年第4期271-275,共5页
Wavelet transforms have been successfully used in seismic data processing with their ability for local time - frequency analysis. However, identification of directionality is limited because wavelet transform coeffici... Wavelet transforms have been successfully used in seismic data processing with their ability for local time - frequency analysis. However, identification of directionality is limited because wavelet transform coefficients reveal only three spatial orientations. Whereas the ridgelet transform has a superior capability for direction detection and the ability to process signals with linearly changing characteristics. In this paper, we present the issue of low signal-to-noise ratio (SNR) seismic data processing based on the ridgelet transform. Actual seismic data with low SNR from south China has been processed using ridgelet transforms to improve the SNR and the continuity of seismic events. The results show that the ridgelet transform is better than the wavelet transform for these tasks. 展开更多
关键词 Ridgelet transform DENOISE marine strata south China non-linear threshold
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Microstructure evolution of Al-Zn-Mg-Cu alloy during non-linear cooling process 被引量:3
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作者 李红英 刘蛟蛟 +2 位作者 余伟琛 赵辉 李德望 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2016年第5期1191-1200,共10页
The microstructure evolution and properties of an Al-Zn-Mg-Cu alloy were investigated under different non-linear cooling processes from the solution temperature, combined with in-situ electrical resistivity measuremen... The microstructure evolution and properties of an Al-Zn-Mg-Cu alloy were investigated under different non-linear cooling processes from the solution temperature, combined with in-situ electrical resistivity measurements, selected area diffraction patterns (SADPs), transmission electron microscopy (TEM), and tensile tests. The relative resistivity was calculated to characterize the phase transformation of the experimental alloy during different cooling processes. The results show that at high temperatures, the microstructure evolutions change from the directional diffusion of Zn and Mg atoms to the precipitation of S phase, depending on the cooling rate. At medium temperatures, q phase nucleates on A13Zr dispersoids and grain boundaries under fast cooling conditions, while S phase precipitates under the slow cooling conditions. The strength and ductility of the aged alloy suffer a significant deterioration due to the heterogeneous precipitation in medium temperature range. At low temperatures, homogeneously nucleated GP zone, η′ and η phases precipitate. 展开更多
关键词 Al-Zn-Mg-Cu alloy microstructure evolution non-linear cooling electrical resistivity mechanical property
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Possible involvement of integrin signaling pathway in the process of recovery from restraint stress in rats 被引量:1
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作者 高玉振 郭试瑜 +3 位作者 印其章 Xiang—Qin CUI 久光正 蒋星红 《Neuroscience Bulletin》 SCIE CAS CSCD 2007年第4期229-235,共7页
Objective To search novel genes or pathways involved in the recovery process after restraint stress in rats. Methods We compared the hypothalamus transcriptional profiles of two different recovery patterns (fast reco... Objective To search novel genes or pathways involved in the recovery process after restraint stress in rats. Methods We compared the hypothalamus transcriptional profiles of two different recovery patterns (fast recovery vs slow recovery) from restraint stress in rats using oligonucleotide microarray, the recovery pattern was determined by the decrement of plasma adrenocorticotropic-hormone (ACTH) and corticosterone levels during one hour recovery period after stress. A real-time quantitative RT-PCR was applied to validate the differential expressed genes. Results Analysis of the microarray data showed that most of genes were not differentially expressed between fast recovery group and slow recovery group. Among the differentially expressed genes we found that talin, together with serine/threonine protein phosphatase PPl-beta catalytic subunit (PP-1B) and integrin α-6 precursor (VLA-6) genes, were at least 1.5 fold upregulated in the fast recovery group, while junctional adhesion molecule 1 (F11r) was 1.5 fold down-regulated in the fast recovery group. Conclusion The results implied that integrin signaling pathway may be involved in the recovery from restraint stress in rats. The present study provided a global overview of hypothalamus transcriptional profiles during the process of recovery from the restraint stress in rats. The integrin signaling pathway seems to be involved in the recovery process, which deserves further study to clarify the integrin-mediated recovery mechanism after restraint stress. 展开更多
关键词 physical restraint adrenocorticotropic hormone CORTICOSTERONE post-stress recovery oligonucleotide microarray
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Restraints and Countermeasures for the Sustainable Development of China's Modern Flower Arrangement Art
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作者 陈佳瀛 徐宝莲 《Journal of Landscape Research》 2009年第10期80-84,共5页
Factors that influence the development of China's modern flower arrangement art are analyzed in this study,countermeasures and suggestions are proposed for the future development.
关键词 MODERN FLOWER arrangement ART restraintS COUNTERMEASURES
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Dip2a regulates stress susceptibility in the basolateral amygdala
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作者 Jing Li Zixuan He +4 位作者 Weitai Chai Meng Tian Huali Yu Xiaoxiao He Xiaojuan Zhu 《Neural Regeneration Research》 SCIE CAS 2025年第6期1735-1748,共14页
Dysregulation of neurotransmitter metabolism in the central nervous system contributes to mood disorders such as depression, anxiety, and post–traumatic stress disorder. Monoamines and amino acids are important types... Dysregulation of neurotransmitter metabolism in the central nervous system contributes to mood disorders such as depression, anxiety, and post–traumatic stress disorder. Monoamines and amino acids are important types of neurotransmitters. Our previous results have shown that disco-interacting protein 2 homolog A(Dip2a) knockout mice exhibit brain development disorders and abnormal amino acid metabolism in serum. This suggests that DIP2A is involved in the metabolism of amino acid–associated neurotransmitters. Therefore, we performed targeted neurotransmitter metabolomics analysis and found that Dip2a deficiency caused abnormal metabolism of tryptophan and thyroxine in the basolateral amygdala and medial prefrontal cortex. In addition, acute restraint stress induced a decrease in 5-hydroxytryptamine in the basolateral amygdala. Additionally, Dip2a was abundantly expressed in excitatory neurons of the basolateral amygdala, and deletion of Dip2a in these neurons resulted in hopelessness-like behavior in the tail suspension test. Altogether, these findings demonstrate that DIP2A in the basolateral amygdala may be involved in the regulation of stress susceptibility. This provides critical evidence implicating a role of DIP2A in affective disorders. 展开更多
关键词 5-HYDROXYTRYPTAMINE acute restraint stress basolateral amygdala CaMKII neurons DIP2A metabolomics NEUROTRANSMITTERS principal component analysis stress susceptibility TRYPTOPHAN
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Design and Optimization for the Occupant Restraint System of Vehicle Based on a Single Freedom Model 被引量:6
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作者 ZHANG Junyuan MA Yue +1 位作者 CHEN Chao ZHANG Yan 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2013年第3期492-497,共6页
Throughout the vehicle crash event, the interactions between vehicle, occupant, restraint system (VOR) are complicated and highly non-linear. CAE and physical tests are the most widely used in vehicle passive safety d... Throughout the vehicle crash event, the interactions between vehicle, occupant, restraint system (VOR) are complicated and highly non-linear. CAE and physical tests are the most widely used in vehicle passive safety development, but they can only be done with the detailed 3D model or physical samples. Often some design errors and imperfections are difficult to correct at that time, and a large amount of time will be needed. A restraint system concept design approach which based on single-degree-of-freedom occupant-vehicle model (SDOF) is proposed in this paper. The interactions between the restraint system parameters and the occupant responses in a crash are studied from the view of mechanics and energy. The discrete input and the iterative algorithm method are applied to the SDOF model to get the occupant responses quickly for arbitrary excitations (impact pulse) by MATLAB. By studying the relationships between the ridedown efficiency, the restraint stiffness, and the occupant response, the design principle of the restraint stiffness aiming to reduce occupant injury level during conceptual design is represented. Higher ridedown efficiency means more occupant energy absorbed by the vehicle, but the research result shows that higher ridedown efficiency does not mean lower occupant injury level. A proper restraint system design principle depends on two aspects. On one hand,the restraint system should lead to as high ridedown efficiency as possible, and at the same time, the restraint system should maximize use of the survival space to reduce the occupant deceleration level. As an example, an optimization of a passenger vehicle restraint system is designed by the concept design method above, and the final results are validated by MADYMO, which is the most widely used software in restraint system design, and the sled test. Consequently, a guideline and method for the occupant restraint system concept design is established in this paper. 展开更多
关键词 vehicle crash occupant restraint system concept design single-degree-of-freedom occupant-vehicle model
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Vibration Characteristics and Power Transmission of Coupled Rectangular Plates with Elastic Coupling Edge and Boundary Restraints 被引量:3
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作者 CHEN Yuehua JIN Guoyong DU Jingtao LIU Zhigang 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2012年第2期262-276,共15页
Coupled-plate structures are widely used in the practical engineering such as aeronautical,civil and naval engineering etc.Limited works can be found on the vibration of the coupled-plate structure due to the increase... Coupled-plate structures are widely used in the practical engineering such as aeronautical,civil and naval engineering etc.Limited works can be found on the vibration of the coupled-plate structure due to the increased mathematical complexity compared with the single plate structure.In order to study analytically the vibration characteristics and power transmission of the coupled-plate structure,an analytical model consisting of three coupled plates elastically restrained along boundary edges and elastically coupled with arbitrary angle is considered,in which four groups of springs are distributed consistently along each edge of the model to simulate the transverse shearing forces,bending moments,in-plane longitudinal forces and in-plane shearing forces separately.With elastic coupling condition and general boundary condition of both flexural and in-plane vibrations taken into account by setting the stiffness of corresponding springs,the double Fourier series solution to the dynamic response of the structure was obtained by employing the Rayleigh-Ritz method.In order to validate the model,the natural frequency and velocity response of the model are firstly checked against results published in literatures and the ANSYS data,and good agreement was observed.Then,numerical simulation of the effects of several relevant parameters on the vibration characteristics and power transmission of the coupled structure were performed,including boundary conditions,coupling conditions,coupling angle,and location of the external forces.Vibration and energy transmission behaviors were analyzed numerically.The results show that the power transmission can be significantly influenced by the boundary restraints and the location of excitation.When the excitation is located at the central symmetry point of the model,the energy flow shows a symmetrical distribution.Once the location deviates from the central symmetry point,the power circumfluence occurs and the vortex energy field is formed at high frequency. 展开更多
关键词 VIBRATION power transmission coupled-plate structure elastic restraints
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Correlation between changes of central neurotransmitter expression and stress response in mice A restraint time-course analysis 被引量:2
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作者 Li Bao Xinsheng Yao +2 位作者 Liang Zhao Yanqing Lü Hiroshi Kurihara 《Neural Regeneration Research》 SCIE CAS CSCD 2008年第2期167-171,共5页
BACKGROUND: Changes in central neurotransmitter expression play an important role in stress response and forms the basis for stress-induced psychological and behavior changes. OBJECTIVE: To observe the effects of di... BACKGROUND: Changes in central neurotransmitter expression play an important role in stress response and forms the basis for stress-induced psychological and behavior changes. OBJECTIVE: To observe the effects of different restraint stress intervals on brain monoamine neurotransmitter expression, and to investigate the correlation between stress response and neurotransmitter levels. DESIGN: Randomized controlled animal study. SETTING: Chinese Herb and Natural Medicine Institute, Pharmacological College of Jinan University. MATERIALS: Sixty 7-week-old male Kunming mice of clean grade, weighing 18-22 g, were provided by the Guangdong Medical Experimental Animal Center. The experiment was in accordance with animal ethics standards. METHODS: This study was performed at the Chinese Herb and Natural Medicine Institute, Pharmacological College of Jinan University from June 2006 to May 2007. A restraint device for mice was constructed according to published reports. Experimental mice were adaptively fed for 1 week and randomly divided into a control group (n = 10) and an experimental group (n = 50). The experimental group was sub-divided into five restraint intervals: 4, 8, 12, 18, and 24 hours (n = 10 mice per time point). Animals in the experimental group were not allowed to eat or drink during the restraint period. Mice in the control group did not undergo restraint, but had identical food and water restrictions. Cerebral cortex and hypothalamus were separated based on observational times and protein was extracted using perchloric acid. Central monoamine neurotransmitter levels were measured using high performance liquid chromatography with electrochemical detection. MAIN OUTCOME MEASURES: Levels of norepinephrine (NE), dopamine hydrochloride (DA), 3,4-dihydroxyphen-ylanetic acid (DOPAC), homovanillic acid (HVA), 5-hydroxytryptamine (5-HT), and 5-hydroxyindoleac-etic acid (5-HIAA) in the cerebral cortex and hypothalamus of mice. RESULTS: Sixty mice were included in the final analysis. ① NE levels in the cerebral cortex, hypothalamus, and plasma: four hours after restraint, NE levels in the cerebral cortex and hypothalamus ere significantly lower than control levels (P 〈 0.05). After 12 hours of restraint, NE levels in the experimental group were significantly higher than in the control group (P 〈 0.05). At 18 hours of restraint, there was no significant difference in NE levels in the cerebral cortex between the experimental group and the control group (P 〉 0.05). In addition, NE levels in the plasma gradually increased with longer restraint time, which was significant between experimental groups and the control group (P 〈 0.05-0.01). ② Levels of DA, DOPAC, and HVA in the cerebral cortex and hypothalamus: there were significant differences in DA levels in the cerebral cortex and hypothalamus after 18 and 24 hours of restraint compared to control animals (P 〈 0.05). DOPAC and HVA levels in the cerebral cortex were enhanced with longer restraint time, and there was significant difference in all restraint groups compared to control levels (P 〈 0.01), except for DOPAC levels after 4 hours of restraint. Moreover, DOPAC and HVA levels in the hypothalamus were enhanced with increasing restraint time. Levels of 5-HT and 5-HIAA in the cerebral cortex and hypothalamus: after short restraint periods and in the control group, 5-HT was not detectable. However, it was quantitatively detected at 12 hours after restraint. The 5-HT levels in the cerebral cortex and hypothalamus reached peak levels at 12 and 18 hours of restraint. 5-HIAA levels in the cerebral cortex and hypothalamus showed a similar tendency to increase with restraint time- 5-HIAA levels at 4-8 hours after restraint were significantly higher than control levels (P 〈 0.01). The 5-HIAA levels decreased at 12 hours after restraint, but remained significantly higher than the control group (P 〈 0.05). CONCLUSION: Restraint stress affects the hypothalamic-pituitary-adrenal (HPA) axis and causes changes in monoamine neurotransmitters in brain tissues, which suggests stress status could be improved by adjusting HPA axis and neurotransmitter levels in the brain. 展开更多
关键词 central monoamine neurotransmitter restraint stress cerebral cortex HYPOTHALAMUS
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EFFECT OF RESTRAINT STRENGTHENING OF VACUUM-PRESSURED BRAZED JOINT 被引量:2
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作者 Wang, Zhongping He, Yong He, Yunjia 《中国有色金属学会会刊:英文版》 EI CSCD 1997年第3期91-94,共4页
EFFECTOFRESTRAINTSTRENGTHENINGOFVACUUMPRESSUREDBRAZEDJOINT①WangZhongping,HeYong,HeYunjiaWeldingDivisionofNo... EFFECTOFRESTRAINTSTRENGTHENINGOFVACUUMPRESSUREDBRAZEDJOINT①WangZhongping,HeYong,HeYunjiaWeldingDivisionofNorthwesternPolytec... 展开更多
关键词 Al Li ALLOYS containing CERIUM VACUUM pressured BRAZING restraint strengthening
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Effect of restraint stress on depression-like behaviors in rats after transient focal cerebral ischemic injury 被引量:2
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作者 Jun Guo Li Liu +3 位作者 Chao Ma Bo Xu Xiaoli Duan Bairen Wang 《Neural Regeneration Research》 SCIE CAS CSCD 2007年第7期390-394,共5页
BACKGROUND: Restraint stress is a typical psychophysiological stressor. Simulating the early passion and difficulty in walking of patients after attack of stroke meets onset features.OBJECTIVE: To evaluate the effec... BACKGROUND: Restraint stress is a typical psychophysiological stressor. Simulating the early passion and difficulty in walking of patients after attack of stroke meets onset features.OBJECTIVE: To evaluate the effect of restraint stress on depression-like behaviors in rats after transient focal cerebral ischemic injury, and to investigate the feasibility for its being as modeling method of depression model after stroke.DESIGN: A randomized controlled animal experiment.SETTING: Department of Clinical Medicine, Faculty of Aerospace Medicine of the Fourth Military Medical University of Chinese PLA.MATERIALS: Forty-eight male Sprague-Dawley rats, weighing 240 - 270 g, provided by the Experimental Animal Center of the Fourth Military Medical University of Chinese PLA were used in the current study.METHODS: The experiments were carried out in the Faculty of Aerospace Medicine of the Fourth Military Medical University of Chinese PLA between August 2005 and August 2006. ①Experiment intervention: The rats were randomized into middle cerebral artery occlusion-reperfusion (MCAO) +stress group, simple MCAO group, sham-operation + stress group and simple sham-operation group, with 12 rats in each group.Rats in the first two groups were developed into cerebral ischemia/reperfusion models by suture-occluded method. Rats in the MCAO+stress group were modeled and restraint stress scheme was performed. At week 5 after modeling, the rats were placed in self-made restraining tubes, 2 hours/time, once a day, for 2 successive weeks. The common carotid artery, external and internal carotid arteries of rats in the latter two groups were exposed. The stress way of sham-operation+ stress group was the same as that of MCAO+ stress group. ②The neurological status grading and motor performance evaluation (screen test, rota-rod test and balance beam test) were conducted in rats with simple sham-operation group and MCAO group before, 1st and 28^th days after modeling. Depression-like behavior test was performed in the rats of each group by sucrose preference test and open field test at the end of the experiment.MAIN OUTCOME MEASURES: Changes of depression-like behaviors of rats in each group.RESULTS: Forty-eight rats were involved in the experiment. Two rats with meningeal irritation sign were excluded from simple MCAO group, and one rat in the MCAO+stress group died of some unclear causes during the experiments. The other 45 rats entered the stage of finial analysis. ① Depression-like behavior assessment results: The rats in the MCAO+ stress group had a significantly decreased preference for sucrose solution, crossing and rearing scores, and increased immobility duration after the 14-day restraint stress,compared with those in other three groups (all P〈0.05). ②The neurological status grading and motor performance evaluation: There were significant differences in the two indexes of rats in the simple MCAO group before, 1^st and 28^th days after modeling (P〈0.01), while there was no significant difference before and 28^th days after modeling (P〉0.05). There were no significant changes in sham-operation group at each time point (P〉0.05).CONCLUSION: After being exerted restraint stress, the rats with transient focal ischemic injury may show obvious depression-like behaviors. Therefore, restraint stress can be used as a novel animal modeling method for further studying biological mechanism in central nervous system of post-stroke depression animals. 展开更多
关键词 transient focal cerebral ischemia restraint stress depressive disorder RATS
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NON-LINEAR FORCED VIBRATION OF AXIALLY MOVING VISCOELASTIC BEAMS 被引量:17
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作者 Yang Xiaodong Chen Li-Qun 《Acta Mechanica Solida Sinica》 SCIE EI 2006年第4期365-373,共9页
The non-linear forced vibration of axially moving viscoelastic beams excited by the vibration of the supporting foundation is investigated. A non-linear partial-differential equation governing the transverse motion is... The non-linear forced vibration of axially moving viscoelastic beams excited by the vibration of the supporting foundation is investigated. A non-linear partial-differential equation governing the transverse motion is derived from the dynamical, constitutive equations and geometrical relations. By referring to the quasi-static stretch assumption, the partial-differential non-linearity is reduced to an integro-partial-differential one. The method of multiple scales is directly applied to the governing equations with the two types of non-linearity, respectively. The amplitude of near- and exact-resonant steady state is analyzed by use of the solvability condition of eliminating secular terms. Numerical results are presented to show the contributions of foundation vibration amplitude, viscoelastic damping, and nonlinearity to the response amplitude for the first and the second mode. 展开更多
关键词 axially moving beam VISCOELASTICITY non-linear forced vibration method of multiple scales
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Characteristics of the Main Journal Bearings of an Engine Based on Non-linear Dynamics 被引量:6
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作者 NI Guangjian ZHANG Junhong CHENG Xiaoming 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2009年第5期755-759,共5页
Many simple nonlinear main journal bearing models have been studied theoretically, but the connection to existing engineering system has not been equally investigated. The consideration of the characteristics of engin... Many simple nonlinear main journal bearing models have been studied theoretically, but the connection to existing engineering system has not been equally investigated. The consideration of the characteristics of engine main journal bearings may provide a prediction of the bearing load and lubrication. Due to the strong non-linear features in bearing lubrication procedure, it is difficult to predict those characteristics. A non-linear dynamic model is described for analyzing the characteristics of engine main journal bearings. Components such as crankshaft, main journals and con rods are found by applying the finite element method. Non-linear spring/dampers are introduced to imitate the constraint and supporting functions provided by the main bearing and oil film. The engine gas pressure is imposed as excitation on the model via the engine piston, con rod, etc. The bearing reaction force is calculated over one engine cycle, and meanwhile, the oil film thickness and pressure distribution are obtained based on Reynolds differential equation. It can be found that the maximum bearing reaction force always occurs when the maximum cylinder pressure arises in the cylinder adjacent to that bearing. The simulated minimum oil film thickness, which is 3 μm, demonstrates the reliability of the main journal bearings. This non-linear dynamic analysis may save computing efforts of engine main bearing design and also is of good precision and close connection to actual engine main journal bearing conditions. 展开更多
关键词 non-linear dynamics ENGINE main journal bearings
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Physical restraints:An ethical dilemma in mental health services in China 被引量:4
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作者 Junrong Ye Aixiang Xiao +3 位作者 Lin Yu Hongmei Wei Chen Wang Tianyun Luo 《International Journal of Nursing Sciences》 2018年第1期68-71,共4页
Given that physical restraints cause adverse effects to patients and nurses,their wide and frequent use has resulted in various clinical and ethical controversies in mental health services.The rate of physical restrai... Given that physical restraints cause adverse effects to patients and nurses,their wide and frequent use has resulted in various clinical and ethical controversies in mental health services.The rate of physical restraints is significantly higher in China than in other countries.Some western and domestic media blamed relevant institutions for compromising the basic rights of psychiatric patients.Therefore,this study aims to collect and synthesize the relevant ethical evidence and to provide corresponding guidance for the nursing practice based on the current situation of the mainland of China.This study synthesized the ethical issue according to the ethical principle of autonomy,justice,beneficence,and nonmaleficence.Given the current situation where the nursing workforce is limited and the mental health service is under-developed in China,applying physical restraints in the psychiatric inpatients to guarantee the safety of patients and nurses is crucial.In regard to respect the basic rights of psychiatric patients,it is recommended to protect the their autonomy,and eliminate the adverse effects of physical restraint.This goal would be achieved by ensuring the informed consent,providing humane care,and regulating the implementation of physical restraints. 展开更多
关键词 ETHICS MENTAL HEALTH NURSING CARE Physical restraint
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Microsphere femtosecond laser sub-50 nm structuring in far field via non-linear absorption 被引量:7
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作者 Zhenyuan Lin Kuan Liu +1 位作者 Tun Cao Minghui Hong 《Opto-Electronic Advances》 SCIE EI CAS CSCD 2023年第6期8-17,共10页
Creation of arbitrary features with high resolution is critically important in the fabrication of nano-optoelectronic devices.Here,sub-50 nm surface structuring is achieved directly on Sb2S3 thin films via microsphere... Creation of arbitrary features with high resolution is critically important in the fabrication of nano-optoelectronic devices.Here,sub-50 nm surface structuring is achieved directly on Sb2S3 thin films via microsphere femtosecond laser irradi-ation in far field.By varying laser fluence and scanning speed,nano-feature sizes can be flexibly tuned.Such small patterns are attributed to the co-effect of microsphere focusing,two-photons absorption,top threshold effect,and high-repetition-rate femtosecond laser-induced incubation effect.The minimum feature size can be reduced down to~30 nm(λ/26)by manipulating film thickness.The fitting analysis between the ablation width and depth predicts that the feature size can be down to~15 nm at the film thickness of~10 nm.A nano-grating is fabricated,which demonstrates desirable beam diffraction performance.This nano-scale resolution would be highly attractive for next-generation laser nano-lithography in far field and in ambient air. 展开更多
关键词 non-linear effect MICROSPHERE femtosecond laser far field
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Occupant Restraint System Simulation and Optimization Based on TESW 被引量:1
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作者 Tian Sheng 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2016年第2期224-230,共7页
Integrated into the development process of a chinese independent brand class sedan,optimization about occupant restraint system associated with dummy chest deceleration is studied.Based on this simulated vehicle decel... Integrated into the development process of a chinese independent brand class sedan,optimization about occupant restraint system associated with dummy chest deceleration is studied.Based on this simulated vehicle deceleration and the target vehicle′s chest deceleration,tipped equivalent square wave(TESW)is calculated by combining the average stiffness kof occupant restraint system and the average free flight time t*from the existant CNCAP(China new car assessment program)tested cars.After proposing modeling regulations of occupant restraint system and establishing mathematical dynamic modelling(MADYMO)for occupant restraint system of the target vehicle,four optimization design parameters namely vent area A,load limit L,seat belt extension ratio Band pretension force Fare selected by weighted injury criteria(WIC)rule and the first-order response surface method.The four parameters have been optimized by using orthogonal test design of four factors with five levels and the optimum combination A5L1B1F5 has been chosen by range and variance analyses.The results show that occupant restraint system performance has been optimized and improved,while meeting the chest deceleration calculation peak based on TESW. 展开更多
关键词 full FRONTAL impact tipped EQUIVALENT SQUARE WAVE OCCUPANT restraint system
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A Non-linear Non-ideal Model of Simulated Moving Bed Chromatography for Chiral Separations 被引量:8
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作者 卢建刚 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2003年第2期234-239,共6页
A non-linear non-ideal model, taking into account non-linear competitive isotherms, axial dispersion, film mass transfer, intraparticle diffusion, and port periodic switching, was developed to simulate the dynamics of... A non-linear non-ideal model, taking into account non-linear competitive isotherms, axial dispersion, film mass transfer, intraparticle diffusion, and port periodic switching, was developed to simulate the dynamics of simulated moving bed chromatography (SMBC). The model equations were solved by a new efficient numerical technique of orthogonal collocation on finite elements with periodical movement of concentration vector. The simulated SMBC performance is in accordance with the experimental results reported in the literature for separation of l,1'-bi-2-naphthol enantiomers using SMBC. This model is useful for design, operation, optimization and scale-up of non-linear SMBC for chiral separations with significant non-ideal effects, especially for high solute concentration and small intraparticle diffusion coefficient or large chiral stationary phase particle. 展开更多
关键词 simulated moving bed chromatography chiral separation non-linear isotherm non-ideal effect DYNAMICS
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Physical restraint in mental health nursing: A concept analysis 被引量:8
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作者 Junrong Ye Chen Wang +6 位作者 Aixiang Xiao Zhichun Xia Lin Yu Jiankui Lin Yao Liao Yu Xu Yunlei Zhang 《International Journal of Nursing Sciences》 CSCD 2019年第3期343-348,共6页
Objective: Physical restraint is frequently used in medical services,such as in mental health settings,intensive care units and nursing homes,but its nature varies in different institutions.By reviewing related litera... Objective: Physical restraint is frequently used in medical services,such as in mental health settings,intensive care units and nursing homes,but its nature varies in different institutions.By reviewing related literature,this study aims to clarify the concept of physical restraint in mental health nursing.Method: Three databases (PubMed,PsyclNFO and CINAHL) were retrieved,and Walker and Avant's concept analysis method was used to analyze the concept of physical restraint in mental health nursing.Results: Physical restraint is a coercive approach that enables the administration of necessary treatment by safely reducing the patient's physical movement.It should be the last option used by qualified personnel.Antecedents of physical restraint are improper behavior (violence and disturbance) of patients,medical assessment prior to implementation and legislation governing clinical usage.Consequences of physical restraint are alleviation of conflict,physical injury,mental trauma and invisible impact on the institution.Discussion: This study defined the characteristics of physical restraint in mental health nursing.The proposed concept analysis provided theoretical foundation for future studies. 展开更多
关键词 Concept analysis Mental health services Physical restraint Qualitative study Walker and Avant's model
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