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Journal of Huazhong University of Science and Technology(medical Sciences) 2004年第5期24卷 424-426页

作者：张蕲胡波孙圣刚邓学军梅元武童萼塘 department of Phathophysiology School of Basic Medical Sciences Tongji Medical College Huazhong University of Science and Technology Wuhan 430030 China department of Neurology Union Hospital Tongji Medical College Huazhong University of Science and Technology Wuhan 430030 China

By using Fura-2.AM, the effects of magnesium (Mg 2.) on the glutamate-induced increase of intracellular free calcium ([Ca 2.]i) in the cultured hippocampal neurons and the features were investigated by integrated photoelectric detecting system. The experiments were designed to three groups (The drug was spit to the cells for 2. s): Group A receiving 1×10 —5 mol/L glutamate; Group B receiving 1×10 —5 mol/L glutamate and1×10 —5 mol/L Mg 2. simultaneously; Group C receiving 1×10 —5 mol/L glutamate again after [Ca 2.]i in group B back to the baseline. The results showed that in group A, [Ca 2.]i was obviously increased. In group B, the changes in [Ca 2.]i and the peak value were significantly decreased. Moreover, the elevation of Phase 1 was slowed down and Phase 2.was shortened to some extent, and the plateau phase between them was relatively prolonged. In group C, calcium oscillation similar to that in group A occurred, but both the Phase 1 and Phase 2.were shortened and the △[Ca 2.]i was slightly decreased. It was suggested that Mg 2. could quickly inhibit the rise of [Ca 2.]i induced by glutamate in the cultured hippocampal neurons in rats.

关键词： magnesium glutamate intracellular free calcium

Robust adaptive backstepping control for a class of uncertain nonlinear systems based on disturbance observers

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Science china(Information Sciences) 2010年第6期53卷 1201-1215页

作者： MEI Rong 1,2. WU QingXian 1 & JIANG ChangSheng 1 1 Automation college, Nanjing University of Aeronautics and Astronautics, Nanjing 2.0016, china 2.Criminal Investigation {2., Nanjing Forest Police college, Nanjing 2.0042. china 1. Automation college Nanjing University of Aeronautics and Astronautics Nanjing 210016 China2. Criminal Investigation Department Nanjing Forest Police College Nanjing 210042 China

In this paper, a novel robust adaptive control scheme for a class of uncertain nonlinear systems is proposed using disturbance observer and backstepping ***, a disturbance observer is developed using radial basis function(RBF) neural *** parameter updated law of the RBF neural network is given for monitoring subsystem disturbance *** robust adaptive control scheme is then presented with backstepping method based on the designed disturbance *** uniform ultimate boundedness(SGUUB) of all signals in the closed-loop uncertain nonlinear system is *** closed-loop system stability analysis shows that semiglobal uniform boundedness of all signals is guaranteed by appropriately choosing design ***, two examples are taken to illustrate the effectiveness of the proposed control scheme.

关键词： uncertain nonlinear systems disturbance observer RBF neural network backstepping control robust adaptive control

The refined theory of deep rectangular beams for symmetrical deformation

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Science china(Physics,Mechanics & Astronomy) 2009年第6期52卷 919-925页

作者： GAO Yang1 & WANG MinZhong2.1 college of Science, china Agricultural University, Beijing 100083, china 2.State Key Laboratory for Turbulence and Complex Systems and department of Mechanics and Aerospace Engineering, Peking University, Beijing 100871, china college of Science China Agricultural University Beijing 100083 China State Key Laboratory for Turbulence and Complex Systems and department of Mechanics and Aerospace Engineering Peking University Beijing 100871 China

Based on elasticity theory, various one-dimensional equations for symmetrical deformation have been deduced systematically and directly from the two-dimensional theory of deep rectangular beams by using the Papkovich-Neuber solution and the Lur'e method without ad hoc assumptions, and they construct the refined theory of beams for symmetrical deformation. It is shown that the displacements and stresses of the beam can be represented by the transverse normal strain and displacement of the mid-plane. In the case of homogeneous boundary conditions, the exact solutions for the beam are derived, and the exact equations consist of two governing differential equations: the second-order equation and the transcendental equation. In the case of non-homogeneous boundary conditions, the approximate governing differential equations and solutions for the beam under normal loadings only and shear loadings only are derived directly from the refined beam theory, respectively, and the correctness of the stress assumptions in classic extension or compression problems is revised. Meanwhile, as an example, explicit expressions of analytical solutions are obtained for beams subjected to an exponentially distributed load along the length of beams.

关键词： deep rectangular beams the refined theory symmetrical deformation the Papkovich-Neuber solution the Lur’e method

Biological decomposition of Na_2._2._3 into sulfur by a newly isolated facultative thermophilic alkaline desulphuricant strain

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Science china Chemistry 2009年第2期52卷 226-230页

作者： ZHANG JianBin1,ZHANG Tong2.MA Kai2.ZHANG PengYan2.LI Qiang2.& WEI XiongHui1 1 department of Applied Chemistry,college of Chemistry & Molecular Engineering,Peking University,Beijing 100190,{2. 2.college of Chemical Engineering,Inner Mongolia University of Technology,Huhhot 010051,{2. 1. department of Applied Chemistry College of Chemistry & Molecular Engineering Peking University Beijing 100190 China 2. college of Chemical Engineering Inner Mongolia University of Technology Huhhot 010051 China

A facultative thermophilic alkaline desulphuricant strain named GDJ-3 was isolated from neutral soils,enriched on sulfur synthetic medium,and detected in previous *** and chemotax-onomic analyses and 16s RNA gene sequencing showed that the strain was in good agreement with Alpha proteobacterium sp.(97%) and ochrobactrum sp.(98%).The regenerative processes of the solu-tion containing sulfur compounds(SCS) from the strain through an orthogonal test were investigated to get the optimum regenerative *** results showed that regenerative temperature,air flow,and stirring speed of the agitator were the main three variables influencing the regenerative processes of the *** optimum regenerative efficiency of the SCS from the strain was obtained when tem-perature,air flow,and stirring speed of the agitator were 318.2.K,3.0 L/min,and zero r/min,*** this condition,when the cell concentration of the strain was adjusted to 107/mL,the concentra-tions of Na2.2.3 and Na2. in the SCS decreased from 112.68 g/L to 96.88 g/L and from 0.87 g/L to 0.11 g/L in 9.5 ***,XRD spectrum shows that sulfur was formed in the regeneration *** results suggest that the strain has potential application to the regeneration of the industrial so-lution containing sulfur compounds.

关键词： bio-desulfurization thermophiles optimization biocomposition orthogonal test

Estrogen stimulates release of secreted amyloid precursor protein from primary rat cortical neurons via protein kinase C pathway

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Acta Pharmacologica Sinica 2005年第2期26卷 171-176页

作者： Sun ZHANG~2.Ying HUANG~2.Yi-chun ZHU~2.Tai YAO~(2.3,4)~2.0} of physiology and Pathophysiology ~3State Key Laboratory for medical Neurobiology,Shanghai medical college of FudanUniversity,Shanghai 2.0032.china department of physiology and Pathophysiology Shanghai medical college of FudanUniversity Shanghai 200032 China

Aim:To investigate the mechanism of the action of estrogen,which stimulates therelease of secreted amyloid precursor protein α(sAPPα)and decreases the gen-eration of amyloid-β protein(Aβ),a dominant component in senile plaques in thebrains of Alzheimer's disease ***:Experiments were carried out inprimary rat cortical neurons,and Western blot was used to detect sAPPα in aculture medium and the total amount of cellular amyloid precursor protein(APP)***:17β-Estradiol(but not 17α-estradiol)and β-estradiol 6-(O-carboxymethyl)oxime:BSA increased the secretion of sAPPα and this effect wasblocked by protein kinase C(PKC)inhibitor calphostin C,but not by the classicalestrogen receptor antagonist ICI 182.***,17β-estradiol did not alterthe synthesis of cellular ***:The effect of 17β-estradiol on sAPPαsecretion is likely mediated through the membrane binding sites,and needs mo-lecular configuration specificity of the ***,the action of the PKC-dependent pathway might be involved in estrogen-induced sAPPα secretion.

关键词： Alzheimer disease estrogen amyloid precursor protein estrogen receptors protein kinase C

Role of melatonin in Alzheimer-like neurodegeneration

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Acta Pharmacologica Sinica 2006年第1期27卷 41-49页

作者： Jian-zhi WANG~(2.4) Ze-fen WANG~(2.3)2.Pathophysiology department,Key Laboratory of Neurological Diseases of Hubei Province,Tongji {2. School,Huazhong University of Science and Technology,Wuhan 430030,china 3 department of physiology,{2. college,Wuhan University Wuhan 430071,china Pathophysiologydepartment KeyLaboratoryofNeurologicalDiseasesofHubeiProvinceTongjiMedicalSchoolHuazhongUniversityoJScienceandTechnologyWuhan430030China departmentofphysiology MedicalCollegeWuhanUniversityWuhan

Alzheimer disease (AD),an age-related neurodegenerative disorder with progres-sive loss of memory and deterioration of comprehensive cognition,is character-ized by extracellular senile plaques of aggregated β-amyloid (Aβ),and intracellularneurofibrillary tangles that contain hyperphosphorylated tau *** showed that melatonin,an indoleamine secreted by the pineal gland,mayplay an important role in aging and AD as an antioxidant and *** decreases during aging and patients with AD have a more profoundreduction in this *** from clinical trials indicate that melatonin supple-mentation improves sleep,ameliorates sundowning,and slows down the progres-sion of cognitive impairment in Alzheimer's *** efficiently pro-tects neuronal cells from Aβ-mediated toxicity via antioxidant and anti-amyloidproperties:it not only inhibits Aβ generation,but also arrests the formation ofamyloid fibrils by a structure-dependent interaction with Aβ.Our recent studieshave demonstrated that melatonin efficiently attenuates Alzheimer-like *** the exact mechanism is still not fully understood,a direct regulatory influence of melatonin on the activities of protein kinases andprotein phosphatases is ***,melatonin also plays a role inprotecting cholinergic neurons and in ***,the neuroprotectiveeffects of melatonin and the underlying mechanisms by which it exerts its effectsare *** capacity of melatonin to prevent or ameliorate tau and Aβpathology further enhances its potential in the prevention or treatment of AD.

关键词： Alzheimer disease melatonin tau,beta amyloid

Rapid quantification of the metabolite of valacyclovir hydrochloride in human plasma by liquid chromatography-tandem mass spectrometry

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Journal of Pharmaceutical Analysis 2010年第2期22卷 83-90页

作者： Yuan Tian1,2.Hui Lin1,2.Xue-Yu Zhang1,2.Zun-Jian Zhang1,2.Guo-Guang Mao31. Key Laboratory of Drug Quality Control and Pharmacovigilance (china Pharmaceutical University),Ministry of Education,Nanjing 2.0009 2. Center for Instrumental Analysis,china Pharmaceutical University,Nanjing 2.0009 3. {2. of Clinical Pharmacology,Wannan medical college,Wuhu 2.1000,china. Key Laboratory of Drug Quality Control and Pharmacovigilance (china Pharmaceutical University) Ministry of Education Nanjing 210009 China Center for Instrumental Analysis China Pharmaceutical University Nanjing 210009 China department of Clinical Pharmacology Wannan Medical College Wuhu 241000 China

Objective To establish a rapid,sensitive and selective liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for the determination of acyclovir (the metabolite of valacyclovir hydrochloride) in human plasma. Methods After addition of ganciclovir as internal standard (IS),plasma samples were prepared by one-step protein precipitation using acetonitrile as precipitant,followed by an isocratic elution with 0.1% formic acid solution-methanol (95∶5,v/v) on an Agilent ZORBAX SB-C18 (150mm×2.1mm i.d.,3.5μm) column. Detection was performed on a triple-quadrupole mass spectrometer utilizing electrospray ionization (ESI) interface operating in positive ion and selected reaction monitoring (SRM) mode with the precursor to product ion transitions m/z 2.6.2.152.1 for acyclovir and m/z 2.6.2.152.1 for the IS. Results The analytical results demonstrated a good linearity over the ranges from 0.005 to 4μg/mL (r=0.9999) for valacyclovir hydrochloride. The relative standard deviations (RSD) of intra-batch and inter-batch were less than 4.06% and 9.2.%,respectively. The limit of detection and lower limit of quantification in human plasma were 2.g/mL and 5ng/mL,respectively. Conclusion The method was simple,sensitive,accurate and reproducible and has been successfully applied to a bioequivalence study of valacyclovir hydrochloride capsules in Chinese healthy male volunteers.

关键词： valacyclovir hydrochloride acyclovir liquid chromatography-tandem mass spectrometry method validation human plasma

Asymptotic behavior of perturbed solution for simple coupled ocean-atmosphere model for ENSO

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Chinese Science Bulletin 2003年第S2期48卷 5-8页

作者： LIN Wantao~1 & MO Jiaqi~2.1. LASG, Institute of Atmospheric Physics. Chinese Academy of Sciences, Beijing 10002., china 2. department of mathematics, Huzhou Normal {2., Huzhou 313000. china Chinese Acad Sci Inst Atmospher Phys LASG Beijing 100029 Peoples R China Huzhou Normal Coll Dept Math Huzhou 313000 Peoples R China

The El Nio/La Nia and the Southern Oscilla-tion are an interannual phenomenon involved in the tropicalPacific Ocean-atmosphere interactions. In this paper, basedon a kind of simple coupled ocean-atmosphere model forENSO, using the perturbed theory and method, the asymp-totic behavior of solution of corresponding problem is stud-ied. It is proved from the results that the trajectories of phaseplane for coupled ocean-atmosphere model ultimately tend tothe stable attractors separately.

关键词： nonlinear perturb ENSO model.

An improved network layer protocol based on mobile IPv6

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Journal of Central South University 2001年第4期8卷 263-267页

作者： WANG Jian xin 1,HUANG Guo sheng 2.CHEN Song qiao 1,CHEN Jian er 1 (1.college of Information Science and Engineering, Central South University, Changsha 410083, china {2. of Physics and Electronic Engineering, Jishou University, Jisho 1. college of Information Science and Engineering Central South University 410083 Changsha China 2. department of Physics and Electronic Engineering Jishou University 416000 Jishou China

The mobile IPv6 proposed by the IETF aims at providing mobility support on the next generation Internet. First, the authors described the basic principle of mobile IPv6 in brief and analyzed the advantages and disadvantages of it, presented a new idea of allocating a specific address space for mobile node (MN) and developed a new extension header and two ICMP message types for mobile IPv6. Lastly the authors proposed an optimization strategy for mobile IPv6 based on these extensions of protocol, which has the following advantages: 1) It is more convenient to manage the MNs because MN can be judged from its IP address; 2. When the correspondent node (CN) is not actively communicating with a MN, the MN and its home agent (HA) need not send Binding Update to the CN, and the CN need not send Binding Request to the MN. Only when the CN really wants to send a packet to the MN, will the CN voluntarily send a MN Discovery Request message to acquire the MN′s care of address. In this way,the transmission of Binding Update and Binding Request is greatly reduced, consequently the network overhead is also decreased; 3) While sending packets, the CN simply uses a MN Home Address Extension Header without using IPinIP encapsulation and routing header, which can reduce the redundant information in the packet and the message delay; 4) All the packets sent by the CN can be directly routed to the MN and the triangle routing can be completely avoided. By using these protocol extensions, the overhead of the network is greatly reduced and the network quality of services (QoS) is improved.

关键词： mobile IP home agent mobile node care of address binding

Nonsingularity in second-order cone programming via the smoothing metric projector

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Science china Mathematics 2010年第4期53卷 1025-1038页

作者： WANG Yun 1,& ZHANG LiWei 2.1 college of Information Sciences and Engineering,Shandong Agricultural University,Tai’an 2.1018,china {2. of Applied Mathematics,Dalian University of Technology,Dalian 11602.,china 1. college of Information Sciences and Engineering Shandong Agricultural University Tai’an 271018 China2. Department of Applied Mathematics Dalian University of Technology Dalian 116024 China

Based on the differential properties of the smoothing metric projector onto the second-order cone,we prove that,for a locally optimal solution to a nonlinear second-order cone programming problem,the nonsingularity of the Clarke's generalized Jacobian of the smoothing Karush-Kuhn-Tucker system,constructed by the smoothing metric projector,is equivalent to the strong second-order sufficient condition and constraint nondegeneracy,which is in turn equivalent to the strong regularity of the Karush-Kuhn-Tucker ***,this nonsingularity property guarantees the quadratic convergence of the corresponding smoothing Newton method for solving a Karush-Kuhn-Tucker ***,the analysis does not need the strict complementarity condition.

关键词： second-order cone programming problem smoothing metric projector B-subdifferential Clarke’s generalized Jacobian smoothing Newton method