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A Semi-Analytical Method for the PDFs of A Ship Rolling in Random Oblique Waves

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China Ocean Engineering 2018年第1期32卷 74-84页

作者： liU li-qin liU Ya-liu xu Wan-hai li Yan TANG You-gang State Key Laboratory of Hydraulic Engineering Simulation and Safety Tianjin University

The PDFs(probability density functions) and probability of a ship rolling under the random parametric and forced excitations were studied by a semi-analytical method. The rolling motion equation of the ship in random oblique waves was established. The righting arm obtained by the numerical simulation was approximately fitted by an analytical function. The irregular waves were decomposed into two Gauss stationary random processes, and the CARMA(2, 1) model was used to fit the spectral density function of parametric and forced excitations. The stochastic energy envelope averaging method was used to solve the PDFs and the probability. The validity of the semi-analytical method was verified by the Monte Carlo method. The C11 ship was taken as an example, and the influences of the system parameters on the PDFs and probability were analyzed. The results show that the probability of ship rolling is affected by the characteristic wave height, wave length, and the heading angle. In order to provide proper advice for the ship’s manoeuvring, the parametric excitations should be considered appropriately when the ship navigates in the oblique seas.

关键词： ship random rolling parametric and forced excitations stochastic energy envelope averaging method probability density function parameter influence analysis

Electro-rheological Effect of Barium Titanate Particles Coated with Urea and Suspended in Methyl Silicone Oil

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Journal of China University of Mining and Technology 2007年第4期17卷 578-581页

作者： ZHANG xu-ping xu ling-li WANG Qing-liang School of Materials and Engineering China University of Mining ＆ Technology Xuzhou 221008 China

Barium titanate nano-powders were synthesized under defined conditions. The surface of these particles was successfully modified by coating with urea. The characteristics of these composite particles were studied by X-ray diffraction,transmission electron microscopy (TEM) and Fourier transform infrared spectroscopy. The electro-rheological (ER) effects of these particles suspended in methyl-silicone oil were measured. The particle,methyl-silicon oil ratio was 30%-35% weight percent. The experimental results indicate that these ER particles exhibit a remarkable ER effect. The ER fluid shows Bingham characteristics and the static shearing stress increases with an increase of the electric field strength. The highest static shearing stress under a 4 MV/m electric field is 13.2 kPa at room temperature,an increase of about 8.7 kPa compared to untreated BaTiO(C2O4)2 powders.

关键词： Barium titanate electro-rheological fluid urea sheafing stress

Effect of salvianolic acid A and C compatibility on inflammatory cytokines in rats with unilateral ureteral obstruction

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Journal of Traditional Chinese Medicine 2015年第5期35卷 564-570页

作者： li Jun Gu Tong Fu xu Zhao Renjie Department of Administration Zunyi Medical College Department of Nephrology the Fifth Affiliated Hospital of Zunyi Medical College

OBJECTIVE:To investigate the effect of salvianolic acid A and C component molecules,which are involved in drug compatibility,on inflammatory cytokine expression that affects human chemokine ligand 5(CCL5) and chemokine ligand 10(CXCL10)levels in rats with unilateral ureteral obstruction(UUO).METHODS:Fifty Sprague Dawley rats were randomly divided into five groups:normal,model,salvianolic acid A,salvianolic acid C and salvianolic acid A and C *** normal group was used as the control,and the other groups of rats had a UUO model *** control group had free access to food and water,and the other groups received the corresponding drugs for 2 *** the last administration,urine β_2-microglobulin(β_2-MG) and N-acetyl-β-D-glucosaminidase(NAG) levels were *** 24 h,all rats were sacrificed and the serum was analyzed for creatinine(Cr) and blood urea nitrogen(BUN) *** kidneys were removed,and CCL5 and CXCL10 inflammatory cytokine mRNA expression was measured using real-time fluorescent quantitative reverse transcription-polymerase chain reaction(RT-PCR).Kidney fibrosis was observed using hematoxylin-eosin(HE)staining and Masson trichrome ***:In the salvianolic acid A and salvianolic acid C treatment groups,serum Cr and urine NAG levels were significantly lower than in the model group(both P lic acid A and C are component molecules of drug compatibility,and they may protect renal function and improve tubular function and renal pathology to a certain degree in *** improvement may be related to a reduction in inflammatory cytokines CCL5 and CXCL10 secretion in the UUO ra

关键词： Salvianolic acid Ureteral obstruction CCL5 protein human CXCL10 protein human Component compatibility

Mailuoning suppresses H_2O_2-induced cortical neuronal injury and correlates with increased catalase activity and inhibited oxidative stress function

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Neural Regeneration Research 2010年第8期5卷 611-617页

作者： Xiaofan Pan Siyuan Huang lingling li Yun xu Department of Neurology Drum Tower Hospital of Nanjing University Medical SchoolNanjing 210008Jiangsu ProvinceChina Departrnent of Neurology Xishan People's HospitalWuxi 214011Jiangsu ProvinceChina Jiangsu Key Laboratory for Molecular Medicine Nanjing 210008 Jiangsu Province China

BACKGROUND：Mailuoning, a Chinese herb, has been widely used in China to treat acute ischemic stroke, and the major component exhibits anti-oxidative effects. However, the precise anti-oxidation pathway remains ***：To validate the protective effects of Mailuoning on H202-induced primary cortical neuron injury in embryonic ***, TIME AND SETTING：Comparative observation and in v#ro experiments were performed at the Jiangsu Key Laboratory for Molecular Medicine from January 2008 to September ***：Mailuoning （Nanjing Jinling Medical Company, China）, reactive oxygen species （ROS） kit （Beyotime Biotechnology, China）, superoxide dismutase （SOD）, Cu/Zn SOD kit, malondialdehyde （MDA） kits （Nanjing Jiancheng, China）, mitochondrial membrane potential （GMS10013.1, GENMED, USA） and catalase activity assay kit （Beyotime Biotechnology, China） were utilized for the present ***：Mouse embryonic cortical neurons were isolated and cultured with culture medium containing H2O2 （80 μmol/L） and/or Mailuoning （1.25 μg/mL） for 24 *** OUTCOME MEASURES：Neuronal viability and death were detected by methyl thiazolyl tetrazdium and flow cytometry; ROS production was determined by flow cytometry; mitochondriai membrane potential was detected using fluorescent staining; SOD activity was detected using a modified nitroblue tetrazolium method; Cu/Zn SOD and catalase activity was detected by spectrophotometry; and MDA was determined using the lipid peroxidation ***：H2O2 increased ROS production and MDA concentration （P 〈 0.05）, and decreased mitochondrial membrane potential, SOD, Cu/Zn SOD and catalase activity （P 〈 0.05）; the number of surviving neurons （P 〈 0.05） was also reduced. Mai/uoning reversed these ***：Mailuoning protects H2O2-induced injury in cortical cells by inhibiting ROS and MDA, increasing depolarization of mitochondrial membrane, and enhancing SOD and catalase activity.

关键词： Mailuoning , oxidative stress neurons reactive oxygen species catalase activity traditional Chinese medicine mice brain injury neural regeneration

Seasonal Changes of Reproductive Activity and Biochemical Composition of Pen Shell Atrina pectinata linnaeus,1767 in Bohai Sea,China

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Journal of Ocean University of China 2017年第3期16卷 479-489页

作者： WANG Changbo li Qi xu Chengxun YU Ruihai Key Laboratory oJMariculture of Ministry of Education Ocean University of China Qingdao 266003 P. R. China

Seasonal variations in the biochemical composition and the reproductive cycle of pen shell Atrina pectinata in Bohai Sea were investigated from May 2013 to April 2014. Histological analysis indicated that the reproductive cycle of A. pectinata can be divided into two phases, inactive stage and gametogenesis, which were equally and significantly influenced by seawater temperature and food availability. Gametogenesis began in late autumn(October), and completed in June and July. Spawning took place in August, coinciding with the highest water temperature and the richest phytoplankton. The significantly high glycogen content in adductor muscles sustained throughout the late active and ripeness stages, but plummeted during spawning and inactive stages. The protein content in female gonads exhibited a synchronous increase along with oocyte diameter and lipid content, suggesting that the female gonads could accumulate protein and lipid for vitelline in A. pectinata. Furthermore, the RNA/DNA ratio was found to be a useful index to indicate the level of gonad maturation in both males and females. The findings of the present study provided a foundation for the fishery resource administration and the aquaculture development of this species.

关键词： biochemical composition reproductive cycle environment factor Atrina pectinata seasonal variation

Visceral Fat Area,Waist Circumference and Metabolic Risk Factors in Abdominally Obese Chinese Adults

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Biomedical and Environmental Sciences 2012年第2期25卷 141-148页

作者： li xu KATASHIMA Mitsuhiro YASUMASU Takeshi liKe Ji Department of Nutrition and Food Hygiene School of Public Health Peking University Health Science Center Beijing 100191 China Health Care Products Research Labs. Tokyo 1318501 Japan

Objective To examine the association of visceral adiposity as measured by VFA and WC with lipid and glucose metabolic biomarkers in abdominally obese Chinese adults,and to assess whether WC could be an indicator of visceral *** WC and VFA were measured in 155 overweight and obese adults.A fasting blood sample was collected from participant（n=118） whose VFA ≥100 cm2 for analyses of lipid and glucose *** relationship between VFA and WC and biomarkers was *** WC and VFA were significantly *** coincidence rate of abdominal obesity determined by Japanese VFA and Chinese WC criteria increased across age quartiles in women from 51.7% to 96.2%.A large WC was associated significantly with low HDL-cholesterol concentration（P0.01） and the association was weakened by additional control of *** and VFA were positively associated with glucose,hemoglobin A1c and insulin concentrations（P0.05 except for the association of VFA with insulin：P0.01）,and all the associations were not significant by additional control of either WC or *** WC quartiles increased,significant stepwise increments in triglyceride,glucose,hemoglobin A1c and insulin and descent in HDL-cholesterol were ***,triglyceride and HDL-cholesterol were not significantly different when compared across VFA *** Higher visceral fat was associated with an adverse lipid and glucose *** can be a moderate predictor for visceral fat and provides a feasible measurement to estimate glucose metabolic *** studies are warranted to establish age-specific WC cutoffs.

关键词： Abdominal fat Waist circumference lipid metabolism Glucose metabolism

Effect of Yizhitongxuan decoction on learning and memory ability,Gαq/11 expression and Na^+-K^+-ATP enzyme activity in rat models of Alzheimer's Disease

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Journal of Traditional Chinese Medicine 2014年第4期34卷 470-476页

作者： Jing Teng Zhexue xu Jing Zhang Jingmin li Department of Internal Traditional Chinese Medicine Shandong University of Traditional Chinese Medicine Department of Medical English Shandong University of Traditional Chinese Medicine

OBJECTIVE: To study the effects of Yizhitongxuan decoction on learning and memory abilities, Gαq/11expression and Na+-K+-ATPenzymeactivityin rat models of Alzheimer's disease(AD) caused by injecting Aβ25-35 into the ***: Ninety male Wistar rats(age ≥10 months)were selected and injected with Aβ25-35 into their hippocampi to establish model animals,which were randomly divided into six groups including a sham-operated group(blank group), a model group, a donepezil HCL group(Western Medicinegroup),and ahigh/general/dilute concentrations of Yizhitongxuan decoction groups(TCMⅠⅡⅢgroup).The Morris watermaze was used to examine the learning and memory abilities of rats in each group by place navigation and spatial probe ***, the rats were sacrificed to collect the hippocampi for biochemical tests, using western blotting to detect the expression of Gαq/11 and an ultramicro Na+-K+-ATP enzyme kit to measure Na+-K+-ATP enzyme ***:Yizhitongxuan decoction improved model rats' learning and memory abilities, and increased the expression of Gαq/11 in the hippocampus and the level of Na+-K+-ATP enzyme activity in ***: Yizhitongxuan decoction could improve model rats' learning and memory abilities,and had a regulating effect on the expression of Gαq/11and Na+-K+-ATP enzyme activity.

关键词： Alzheimer disease Sodium-potassium-exchanging ATPase Learning and memory ability Yizhitongxuan decoction

Inhibitory effect induced by fractional Gaussian noise in neuronal system

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Chinese Physics B 2023年第1期32卷 145-152页

作者：李智坤李东喜 College of Mathematics Taiyuan University of TechnologyTaiyuan 030024China College of Data Science Taiyuan University of TechnologyTaiyuan 030024China

We discover a phenomenon of inhibition effect induced by fractional Gaussian noise in a neuronal system. Firstly,essential properties of fractional Brownian motion(fBm) and generation of fractional Gaussian noise(fGn) are presented,and representative sample paths of fBm and corresponding spectral density of fGn are discussed at different Hurst ***, we consider the effect of fGn on neuronal firing, and observe that neuronal firing decreases first and then increases with increasing noise intensity and Hurst index of fGn by studying the time series evolution. To further quantify the inhibitory effect of fGn, by introducing the average discharge rate, we investigate the effects of noise and external current on neuronal firing, and find the occurrence of inhibitory effect about noise intensity and Hurst index of f Gn at a certain level of current. Moreover, the inhibition effect is not easy to occur when the noise intensity and Hurst index are too large or too small. In view of opposite action mechanism compared with stochastic resonance, this suppression phenomenon is called inverse stochastic resonance(ISR). Finally, the inhibitory effect induced by fGn is further verified based on the inter-spike intervals(ISIs) in the neuronal system. Our work lays a solid foundation for future study of non-Gaussian-type noise on neuronal systems.

关键词： inhibitory effect inverse stochastic resonance fractional Gaussian noise neuronal system

Study on Internal Waves Generated by Tidal Flow over Critical Topography

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Journal of Ocean University of China 2014年第5期13卷 728-732页

作者： JIA Xiaona CHEN xu li Qun li Qiang Key Laboratory of Physical Oceanography Ocean University of China SOA Key Laboratory for Polar Science Polar Research Institute of China Center for Ocean Science and Technology Graduate School at Shenzhen Tsinghua University

Resonance due to critical slope makes the internal wave generation more effectively than that due to supercritical or subcritical slopes(Zhang et al., 2008). Submarine ridges make a greater contribution to ocean mixing than continental margins in global oceans(Müller, 1977; Bell, 1975; Baines, 1982; Morozov, 1995). In this paper, internal wave generation driven by tidal flow over critical topography is examined in laboratory using Particle Image Velocimetry(PIV) and synthetic schlieren methods in synchrony. Non-tidal baroclinic velocities and vertical isopycnal displacements are observed in three representative regions, i.e., critical, outward-propagating, and reflection regions. Temporal and spatial distributions of internal wave rays are analyzed using the time variations of baroclinic velocities and vertical isopycnal displacement, and the results are consistent with those by the linear internal wave theory. Besides, the width of wave beam changes with the outward propagation of internal waves. Finally, through monitoring the uniformly-spaced 14 vertical profiles in the x-z plane, the internal wave fields of density and velocity fields are constructed. Thus, available potential energy, kinetic energy and energy fluxes are determined quantitatively. The distributions of baroclinic energy and energy fluxes are confined along the internal wave rays. The total depth averaged energy and energy flux of vertical profiles away from a ridge are both larger than those near the ridge.

关键词： internal waves critical topography available potential energy kinetic energy baroclinic energy flux