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Effects of electroacupuncture at Guanyuan(CV 4)or Sanyinjiao(SP 6)on hypothalamus-pituitary-ovary axis and spatial learning and memory in female SAMP8 mice

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Journal of Traditional Chinese Medicine 2017年第1期37卷 96-100页

作者： Wang Jing Cheng Kai Qin Zhuo Wang Yanping Zhai Lijing You Min Wu Juanjiao School of Acupuncture Moxibustion and TuinaBeijing University of Chinese MedicineBeijing 100029China

OBJECTIVE: To investigate the effects of electroacupuncture(EA) at the Guanyuan(CV 4) or Sanyinjiao(SP 6) acupoints on the hypothalamus-pituitary-ovary(HPO) axis and spatial learning and memory in female mice.METHODS: Nine-month-old female mice with senescence-accelerated mouse prone 8(SAMP8)were divided into three groups: the disease model,EA-Guanyuan and EA-Sanyinjiao groups. Concurrently, 9-month old female mice with senescence-accelerated mouse resistance 1(SAMR1)were set as the control model group. The two treatment groups were given the same pattern of EA stimulation. Gonadotropin-releasing hormone, luteinizing hormone, follicle-stimulating hormone(FSH) and Serum estradiol levels in the Hypothalamus-pituitary-ovary axis were assessed by enzyme-linked immunosorbent assay to determinethe HPO axis function level. Spatial learning and memory were assessed by the Morris Water Maze(MWM) test.RESULTS:(a) HPO axis: compared with the control model group, the disease model group displayed a decrease in E2 levels(P memory ability in female SAMP8 mice. Moreover, this effect may have been more pronounced in the EA-Sanyinjiao group than the EA-Guanyuan group. The underlying mechanism of the EA-induced changes may be related to gonadal hormone shifts in the HPO axis, followed by an improvement in spatial learning and memory.

关键词： Alzheimer disease Electroacupuncture Point CV 4(Guanyuan) Point SP 6(Sanyinjiao) Spatial learning memory Hypothalamus-pituitary-ovary axis

Can bispectral index or auditory evoked potential index predict implicit memory during propofol-induced sedation?

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Chinese Medical Journal 2006年第11期119卷 894-898页

作者： WANG Yun YUE Yun SUN Yong-hai WU An-shi Department of Anaesthesiology Beijing Chaoyang Hospital Capital University of Medical Sciences Beijing100020 China Department of Anaesthesiology Beijing Chaoyang Hospital Capital University of Medical Sciences Beijing 100020 China 　Department of Anaesthesiology PLA General Hospital Beijing 100853 China Department of Anaesthesiology Beijing Chaoyang Hospital Capital University of Medical Sciences Beijing 100020 China　

Background Some patients still suffer from implicit memory of intraoperative events under adequate depth of anaesthesia. The elimination of implicit memory should be a necessary aim of clinical general anaesthesia. However, implicit memory cannot be tested during anaesthesia yet. We propose bispectral index （BIS） and auditory evoked potential index （AEPI）, as predictors of implicit memory during anaesthesia. Methods Thirty-six patients were equally divided into 3 groups according to the Observer＇s Assessment of Alertness/Sedation Score： A, level 3; B, level 2 ;and C, level 1. Every patient was given the first auditory stimulus before sedation. Then every patient received the second auditory stimulus after the target level of sedation had been reached. BIS and AEPI were monitored before and after the second auditory stimulus presentation. Four hours later, the inclusion test and exclusion test were performed on the ward using process dissociation procedure and the scores of implicit memory estimated. Results In groups A and B but not C, implicit memory estimates were statistically greater than zero （P〈0.05）. The implicit memory scores in group A did not differ significantly from those in group B （P〉0.05）. Implicit memory scores correlated with BIS and AEPI （P〈0.01）. The area under ROC curve is BIS〉 AEPI. The 95% cutoff points of BIS and AEPI for predicting implicit memory are 47 and 28, respectively. Conclusions Implicit memory does not disappear until the depth of sedation increases to level 1 of OAA/S score. Implicit memory scores correlate well with BIS and AEPI during sedation. BIS is a better index for predicting implicit memory than AEPI during propofol induced sedation.

关键词： memory anesthetic propofol electroencephalography evoked potentials, auditory

In memory of Prof. C. C. Li

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Protein & Cell 2019年第6期10卷 389-392页

作者： Zhi Xia Juan Tian Xiaoling Wang Huanming Yang BGI-Shenzhen Shenzhen 518083 China

Professor Ching Chun Li (C. C. Li), one of the greatest geneticists in the world and a pioneer of genetics in China, passed away fifteen years ago (Fig. 1). Let us remember him together.**Do you know who the greatest, world-renown Chinese geneticist is?" The answer,**C. C. Li, of course!” would puzzle most, if not all, of us;many in our generation don't know Who is Who (Atte ntion! Li, not Lee, the latter of which was gen erally used as the general spelli ng of that gen eration)(Fig. 2).

关键词： In memory of Prof.C.C.Li greatest geneticists latter

Pb(Zr_(0.52)Ti_(0.48))O_3 memory capacitor on Si with a polycrystalline silicon/SiO_2 stacked buffer layer

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Journal of Semiconductors 2011年第9期32卷 54-57页

作者：蔡道林李平翟亚红宋志棠陈后鹏 State Key Laboratory of Functional Materials for Informatics Laboratory of NanotechnologyShanghai Institute of Microsystems and Information TechnologyChinese Academy of Sciences State Key Laboratory of Electronic Thin Films and Integrated Devices University of Electronic Science and Technology of China

Pb（Zr_（0.52）Ti_（0.48））O_3（PZT） thin films have been deposited on a p-type Si substrate separated by a polycrystalline silicon/SiO_2 stacked buffer layer.The X-ray diffraction peaks of the PZT thin films prepared on the polycrystalline silicon annealed at different temperatures were measured.In addition,the polarization of the Pt/PZT/polycrystalline silicon capacitor has been investigated.The memory capacitor of the metal/ferroelectric/polycrystalline silicon/SiO_2/semiconductor structure annealed at 650℃exhibits a clockwise capacitance-voltage hysteresis loop due to the ferroelectric polarization of the PZT thin film.The memory window increases with increasing the area coupling ratio between the SiO_2 capacitor and the PZT capacitor.

关键词： capacitor thin film memory

4D printing of personalized shape memory polymer vascular stents with negative Poisson’s ratio structure:A preliminary study

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Science China(Technological Sciences) 2020年第4期63卷 578-588页

作者： LIN Cheng ZHANG LiJin LIU YanJu LIU LiWu LENG JinSong Department of Astronautic Science and Mechanics Harbin Institute of Technology(HIT)Harbin 150001China National Key Laboratory of Science and Technology on Advanced Composites in Special Environments Harbin Institute of Technology(HIT)Harbin 150080China

Four-dimensional(4D)printing,integrates transformation information into three-dimensional(3D)-printed structures,which means that 3D-printed structures are able to change their shapes,properties,or functionalities over time.Here,two types of shape memory personalized vascular stents with negative Poisson’s ratio structure are developed via 4D printing.The genetic algorithm is used to optimize the structure.Axial compression tests,radial compression tests and three-point bending tests are carried out to study the mechanical properties of the stents.In addition,fluid-structure interaction and stress distribution during the shape recovery process are investigated based on finite element method.The shape memory behaviors of the stents are excellent and in vitro feasibility tests demonstrate that the stents can expand the simulated narrow blood vessel rapidly.Therefore,4D printed shape memory stents with negative Poisson’s ratio structure are highly promising for the treatment of vascular stenosis.

关键词： shape memory polymer 4D printing biodegradable vascular stents finite element analysis negative Poisson's ratio

Three-dimensional constitutive model for magneto-mechanical deformation of NiMnGa ferromagnetic shape memory alloy single crystals

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Acta Mechanica Sinica 2019年第3期35卷 563-588页

作者： Chao Yu Guozheng Kang Di Song Xi Xie State Key Laboratory of Traction Power Southwest Jiaotong UniversityChengdu 610031China Applied Mechanics and Structure Safety Key Laboratory of Sichuan Province School of Mechanics and EngineeringSouthwest Jiaotong UniversityChengdu 610031China School of Mechatronics Engineering University of Electronic Science and Technology of ChinaChengdu 610031China

Existing experimental results have shown that four types of physical mechanisms, namely, martensite transformation, martensite reorientation, magnetic domain wall motion and magnetization vector rotation, can be activated during the magneto-mechanical deformation of NiMnGa ferromagnetic shape memory alloy (FSMA) single crystals. In this work, based on irreversible thermodynamics, a three-dimensional (3D) single crystal constitutive model is constructed by considering the aforementioned four mechanisms simultaneously. Three types of internal variables, i.e., the volume fraction of each martensite variant, the volume fraction of magnetic domain in each variant and the deviation angle between the magnetization vector, and easy axis are introduced to characterize the magneto-mechanical state of the single crystals. The thermodynamic driving force of each mechanism and the thermodynamic constraints on the constitutive model are obtained from Clausius's dissipative inequality and constructed Gibbs free energy. Then, thermodynamically consistent kinetic equations for the four mechanisms are proposed, respectively. Finally, the ability of the proposed model to describe the magneto-mechanical deformation of NiMnGa FSMA single crystals is verified by comparing the predictions with corresponding experimental results. It is shown that the proposed model can quantitatively capture the main experimental phenomena. Further, the proposed model is used to predict the deformations of the single crystals under the non-proportional mechanical loading conditions.

关键词： Ferromagnetic shape memory alloys Single crystals Magneto-mechanical deformation Martensite transformation Martensite reorientation Constitutive model

Influence of process factors on shape memory effect of CuZnAl alloys

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Transactions of Nonferrous Metals Society of China 2006年第6期7卷 1402-1409页

作者：刘海霞司乃潮徐桂芳 School of Materials Science and Engineering Jiangsu University

Thermal cycle training of CuZnAl shape memory alloys with different transformation temperatures was carried out.The influence of different pre-strains,heat treatments and media on the shape memory effect(SME)of CuZnAl alloys with different transformation temperatures was studied by means of scanning electron microscopy(SEM)and X-ray diffractometry(XRD).Experimental results show that despite respective variation in heat treatment,medium and cycling number,the recovery rate always decreases as pre-strain increases.The decline is obvious when pre-strain is less than 2.6% but not so sharp when pre-strain exceeds 2.6%.Larger pre-strain results in more than one slip system and causes intercutting of the martensite strips among martensitic variants,then leads to the decline of SME.The SME of alloys with transformation temperatures below 347 K is larger than that of alloys beyond 361 K by 20%?40%.The recovery rate of two-step aged alloy is higher than that of step-quenched alloy by 20%?25%.During thermal cycling,the recovery rate in oil is better than that in water.

关键词： CuZnAl shape memory alloys pre-strain transformation temperature shape memory effect thermal cycling

Effects of H_2O_2 pretreatment on surface characteristics and bioactivity of NaOH-treated NiTi shape memory alloy

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Transactions of Nonferrous Metals Society of China 2006年第6期7卷 1295-1300页

作者：储成林胡涛周俊浦跃朴尹立红董寅生林萍华钟志源朱剑豪 School of Materials Science and Engineering Southeast University School of Public Health Southeast University Department of Physics and Materials Science City University of Hong Kong Hong KongChina

The effects of H2O2 pretreatment on the surface characteristics and bioactivity of NaOH-treated NiTi shape memory alloy(SMA)were investigated by scanning electron microscopy,X-ray diffraction,X-ray photoelectron spectroscopy,Raman spectra,Fourier transform infrared spectroscopy as well as a simulated body fluid(SBF)soaking test.It is found that the H2O2 pretreatment can lead to the direct creation of more Ti—OH groups and the decrease in the amount of Ni2O3,Na2TiO3 and remnant NiTi phases on the surfaces of bioactive NiTi SMA prepared by NaOH treatment.As a result,the induction period of apatite formation is shortened by dispensing with the slow kinetic formation process of Ti—OH groups via an exchange of Na+ ions from Na2TiO3 phase with H3O+ ions in SBF,which indicates that the bioactivity of NaOH-treated NiTi SMA can be further improved by the H2O2 pretreatment.

关键词： shape memory alloy(SMA) NiTi NaOH treatment surface structure bioactivity H2O2 pretreatment

Microwave sintering effects on the microstructure and mechanical properties of Ti–51at%Ni shape memory alloys

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International Journal of Minerals,Metallurgy and Materials 2017年第3期24卷 280-288页

作者： Mustafa K. Ibrahim E. Hamzah Safaa N. Saud E. N. E. Abu Bakar A. Bahador Faculty of Mechanical Engineering Universiti Teknologi Malaysia 81310 UTM Johor Bahru Johor Malaysia Faculty of Information Sciences and Engineering Management & Science University Shah Alam Selangor Malaysia

Ti–51at%Ni shape memory alloys(SMAs) were successfully produced via a powder metallurgy and microwave sintering technique.The influence of sintering parameters on porosity reduction,microstructure,phase transformation temperatures,and mechanical properties were investigated by optical microscopy,field-emission scanning electron microscopy(FE-SEM),X-ray diffraction(XRD),differential scanning calorimetry(DSC),compression tests,and microhardness tests.Varying the microwave temperature and holding time was found to strongly affect the density of porosity,presence of precipitates,transformation temperatures,and mechanical properties.The lowest density and smallest pore size were observed in the Ti–51at%Ni samples sintered at 900°C for 5 min or at 900°C for 30 min.The predominant martensite phases of β2 and β19′ were observed in the microstructure of Ti–51at%Ni,and their existence varied in accordance with the sintering temperature and the holding time.In the DSC thermograms,multi-transformation peaks were observed during heating,whereas a single peak was observed during cooling;these peaks correspond to the presence of the β2,R,and β19′ phases.The maximum strength and strain among the Ti–51at%Ni SMAs were 1376 MPa and 29%,respectively,for the sample sintered at 900°C for 30 min because of this sample's minimal porosity.

关键词： titanium nickel alloys shape memory effect powder metallurgy (PM) microwave heating sintering microstructure mechanical properties