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Investigation of one-lung ventilation postoperative cognitive dysfunction and regional cerebral oxygen saturation relations

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2015年第12期16卷 1042-1048页

作者： Xi-ming LI Feng LI zhong-kai liu Ming-tao SHAO Department of Anesthesiology Linyi City People's Hospital Human Resource Department Linyi City People's Hospital Department of Emergency Surgery Linyi City People's Hospital

Objective： To explore the relationship of postoperative cognitive dysfunction （POCD） in one-lung ventilation （OLV） patients and regional cerebral oxygen saturation （rSO2）. Methods： Twenty-nine male and twenty-one female cases of OLV received thoracic surgery, with American Standards Association （ASA） physical status being at Grades Ⅰ-Ⅲ. Neuropsychological tests were performed on the day before operation and 7 d after operation, and there was an intraoperative continuous monitoring of rSO2. The values of rSO2 before anesthesia induction （t1）, at the beginning of OLV （t2）, and at the time of OLV 30 min （t3）, OLV 60 min （t4）, the end of OLV （t5）, and the end of surgery （t6） were recorded. The intraoperative average of rSO2 （ rSO2 ）, the intraoperative minimum value of rSO2 （rSO2, rn=n）, and the reduced maximum percentage of rSO2 （rSO2, %max） when compared with the baseline value were calculated. The volume of blood loss, urine output, and the amount of fluid infusion was recorded. Results： A total of 14 patients （28%） in the 50 cases suffered from POCD. The values of mini-mental state examination （MMSE）, the digit span and the digit symbol on the 7th day after the operation for POCD in OLV patients were found to be significantly lower than those before the operation （P〈0.05）. The values of MMSE and vocabulary fluency scores were significantly lower than those in the non-POCD group （P〈0.05）. The values of rSO2 in the POCD group of OLV patients at t2 and t3 and the values of rSO2 in the non-POCD group at t2 were found to be significantly higher than those at tl （P〈0.05）. The values of rSO2, %max in the POCD group were significantly higher than those in the non-POCD group （P〈0.05）. When the value of rSO2, %max is more than 10.1%, it may act as an early warning index for cognitive function changes, Conclusions： POCD after OLV may be associated with a decline in rSO2.

关键词： One-lung ventilation Postoperative cognitive dysfunction Regional cerebral oxygen saturation

Neuroprotection of dexmedetomidine against propofol-induced neuroapoptosis partly mediated by PI3K/Akt pathway in hippocampal neurons of fetal rat

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2017年第9期18卷 789-796页

作者： Ning ZHANG Quan-ping SU Wei-xia ZHANG Nian-jun SHI Hao ZHANG Ling-ping WANG zhong-kai liu Ke-zhong LI Department of Anesthesiology the Second Hospital of Shandong University Department of Anesthesiology Linyi People’s Hospital The Central Laboratory Linyi Peoples’ Hospital Intensive Care Unit Linyi People’s Hospital

The aim was to investigate how the PI3K/Akt pathway is involved in the protection of dexmedetomidine against propofol. The hippocampal neurons from fetal rats were separated and cultured in a neurobasal medium. Cell viability was assayed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide(MTT) assay. Then neurons were pretreated with different concentrations of dexmedetomidine before 100 μmol/L propofol was added. Akt, phospho-Akt(p-Akt), Bad, phospho-Bad(p-Bad), and Bcl-x L were detected by Western blot. Also, neurons were pretreated with dexmedetomidine alone or given the inhibitor LY294002 before dexmedetomidine pretreatment, and then propofol was added for 3h. The results demonstrated that propofol decreased the cell viability and the expression of p-Akt and p-Bad proteins, increased the level of Bad, and reduced the ratio of Bcl-x L/Bad. Dexmedetomidine pretreatment could reverse these effects. The enhancement of p-Akt and p-Bad induced by dexmedetomidine was prevented by LY294002. These results showed that dexmedetomidine potently protected the developing neuron and this protection may be partly mediated by the PI3K/Akt pathway.

关键词： Dexmedetomidine Propofol Neuroapoptosis PI3K/Akt

Measurement of the electronic structure of a type-Ⅱ topological Dirac semimetal candidate VAI_(3) using angle-resolved photoelectron spectroscopy

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钨科技(英文) 2023年第3期5卷 332-338页

作者： Hong-Wei Fang Ai-Ji Liang Niels B.M.Schroter Sheng-Tao Cui zhong-kai liu Yu-Lin Chen School of Physical Science and Technology ShanghaiTech UniversityShanghai 201210China University of Chinese Academy of Sciences Beijing 100049China ShanghaiTech Laboratory for Topological Physics ShanghaiTech UniversityShanghai 201210China Max Planck Institute of Microstructure Physics Halle 06120Germany National Synchrotron Radiation Laboratory University of Science and Technology of ChinaHefei 230029China Department of Physics University of OxfordOxford OX13PUUnited Kingdom

Type-Ⅱ topological Dirac semimetals are topological quantum materials hosting Lorentz-symmetry breaking type-Ⅱ Dirac fermions,which are tilted Dirac cones with various exotic physical properties,such as anisotropic chiral anomalies and novel quantum *** now,only limited material systems have been confirmed by theory and experiments with the type-Ⅱ Dirac ***,we investigated the electronic structure of a new type-Ⅱ Dirac semimetal VA1_(3) with angle-resolved photoelectron *** measured band dispersions are consistent with the theoretical prediction,which suggests the Dirac points are located close to(at about 100 meV above) the Fermi *** work demonstrates a new type-Ⅱ Dirac semimetal candidate system with different Dirac node configurations and application potentials.

关键词： Dirac semimetal.Electronic structure Angle-resolved photoelectron spectroscopy K evaporation

Hydrogen and nitrogen absorption properties of Ce-added Zr_(2)(Fe_(1-x)Ni_(x)) alloys

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Journal of Rare Earths 2024年第6期42卷 1136-1141,I0005页

作者： kai Yin Xiaopeng liu State Key Laboratory of Advanced Materials for Smart Sensing GRINM Group Co.Ltd.Beijing10088China GRIMAT Engineering Institute Co. Ltd.Beijing101407China General Research Institute of Nonferrous Metals Beijing100088China

To improve the nitriding resistance of Zr_(2)Fe alloy,the Ce-added Zr_(2)(Fe_(1-x)Ni_(x))(x=0,0.15,0.3,0.5)alloys were prepared by magnetic levitation melting *** effects of Ni substitution for Fe on the phase structure,hydrogen and nitrogen absorption properties of the alloys were investigated by X-ray diffraction,scanning electron microscopy and p-c isotherm *** experimental results show that Ni substitution can effectively inhibit the formation of both α-Zr and ZrFe_(2) phases and promote the formation of C16 structure Zr_(2)(Fe,Ni)phase,causing Ni-substituted alloys to exhibit low nitrogen absorption rate and *** 623 K under 0.5 MPa nitrogen pressure,the nitrogen absorption capacity of Ce-added Zr_(2)(Fe_(0.5)Ni_(0.5))alloy reaches to 0.8 mL/g,much lower than that of Zr_(2)Fe alloy(1.5 mL/g).Ni substitution decreases the crystal cell volume of the C_(16)Zr_(2)(Fe,Ni)phase,resulting in an increase in the hydrogen absorption equilibrium *** 623 K under 0.05 MPa hydrogen pressure,the hydrogen absorption capacity decreases from 1.46 wt%of Zr_(2)Fe alloy to 1.41 wt%of Ce-added Zr_(2)(Fe_(0.5)Ni_(0.5))alloy.

关键词： Zr_(2)Fe alloy Ce Pressure-composition isotherm Hydrogen absorption Nitrogen absorption Rare earths

Switchable shape memory polymer bio-inspired adhesive and its application for unmanned aerial vehicle landing

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Chinese Journal of Aeronautics 2024年第3期37卷 380-390页

作者： Qingsong HE Zefang ZHAO Qiyun zhong Siyuan liu kai DENG Yongqi liu Ning ZHANG Zijie ZHAO Fengjiang ZHAN Jianfeng ZHAO Jiangsu Provincial Key Laboratory of Bionic Functional Materials College of Mechanical and Electrical EngineeringNanjing University of Aeronautics and AstronauticsNanjing 210016China Key Laboratory of Advanced Technology for Small and Medium-Sized UAV Ministry of Industry and Information TechnologyUnmanned Aerial Vehicles Research InstituteNanjing University of Aeronautics and AstronauticsNanjing 210016China State Key Laboratory of Mechanics and Control of Aerospace Structures Nanjing University of Aeronautics and AstronauticsNanjing 210016China Functional Morphology and Biomechanics Institute of ZoologyKiel UniversityKiel 24098Germany

Controlled and switchable adhesion is commonly observed in biological *** recent years,many scholars have focused on making switchable bio-inspired ***,making a bio-inspired adhesive with high adhesion performance and excellent dynamic switching properties is still a challenge.A Shape Memory Polymer Bio-inspired Adhesive(SMPBA)was successfully developed,well realizing high adhesion(about 337 kPa),relatively low preload(about90 kPa),high adhesion-to-preload ratio(about 3.74),high switching ratio(about 6.74),and easy detachment,which are attributed to the controlled modulus and contact area by regulating temperature and the Shape Memory Effect(SME).Furthermore,SMPBA exhibits adhesion strength of80–337 kPa on various surfaces(silicon,iron,and aluminum)with different roughness(Ra=0.021–10.280)because of the conformal contact,reflecting outstanding surface *** finite element analysis verifies the bending ability under different temperatures,while the adhesion model analyzes the influence of preload on contact area and ***,an Unmanned Aerial Vehicle(UAV)landing device with SMPBA was designed and manufactured to achieve UAV landing on and detaching from various *** study provides a novel switchable bio-inspired adhesive and UAV landing method.

关键词： Bio-inspired adhesive Shape memory polymers Switchable adhesive Unmanned aerial vehicle Landing

Exploring charge and spin fluctuations in infinite-layer cuprate SrCuO_(2)from a phonon perspective

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Science China(Physics,Mechanics & Astronomy) 2024年第8期67卷 159-167页

作者： Xin Du Pei-Han Sun Ben-Chao Gong Jian-Feng Zhang zhong-Yi Lu kai liu Department of Physics and Beijing Key Laboratory of Opto-electronic Functional Materials&Micro-nano Devices Renmin University of ChinaBeijing 100872China Department of Physics School of ScienceJiangsu University of Science and TechnologyZhenjiang 212100China Institute of Physics Chinese Academy of SciencesBeijing 100190China Key Laboratory of Quantum State Construction and Manipulation(Ministry of Education) Renmin University of ChinaBeijing 100872China

The infinite-layer cuprate ACu O_(2)(A=Ca,Sr,Ba)possesses the simplest crystal structure among numerous cuprate superconductors and can serve as a prototypical system to explore the unconventional *** on the first-principles electronic structure calculations,we have studied the electronic and magnetic properties of the infinite-layer cuprate SrCuO_(2)from a phonon *** find that interesting fluctuations of charges,electrical dipoles,and local magnetic moments can be induced by the atomic displacements of phonon modes in SrCuO_(2)upon the hole *** all optical phonon modes of SrCuO_(2)in the antiferromagnetic Néel state,only the A_(1g)mode that involves the full-breathing O vibrations along the Cu-O bonds can cause significant fluctuations of local magnetic moments on O atoms and dramatic charge redistributions between Cu and O ***,due to the atomic displacements of the A_(1g)mode,both the charge fluctuations on Cu and the electrical dipoles on O show a dome-like evolution with increasing hole doping,quite similar to the experimentally observed behavior of the superconducting T_(c);in comparison,the fluctuations of local magnetic moments on O display a monotonic enhancement along with the hole *** analyses indicate that around the optimal doping,there exists a large softening in the frequency of the A_(1g)phonon mode and a van Hove singularity in the electronic structure close to the Fermi level,suggesting potential electron-phonon *** work reveals the important role of the full-breathing O phonon mode playing in the infinite-layer SrCuO_(2),which may provide new insights in understanding the cuprate superconductivity.

关键词： first-principles calculations cuprate superconductors phonon charge and spin fluctuations

Research on the navigation method of large-scale differential tail-control improvised guided munitions based on rotational speed constraints

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Defence Technology（防务技术） 2024年第8期38卷 155-170页

作者： Ning liu Wenjiang Zhao Yao Wang kai Shen zhong Su Wenhao Qi Yuedong Xie Beijing Key Laboratory of High Dynamic Navigation Technology Beijing Information Science and Technology UniversityBeijing100192China Hua an Industry Group Co. Ltd.Qiqihar161006China Integrated Navigation and Intelligent Navigation Laboratory Beijing Institute of TechnologyBeijing100081China Beijing Institute of Technology Beijing100081China

In the process of launching guided projectile under the conventional system, it is difficult to effectively obtain the precise navigation parameters of the projectile in the high dynamic environment. Aiming at this problem, this paper describes a new system of guided ammunition based on tail spin reduction. After analyzing the mechanism of the ammunition's tail spin reduction, a navigation method of large scale difference tail control simple guided ammunition based on speed constraint is proposed. In this method,the corresponding navigation constraints can be carried out by combining the rotation speed state of the ammunition itself, and the optimal solution of navigation parameters during the flight of the missile can be obtained by Extended Kalman Filter(EKF). Finally, the performance of the proposed method was verified by the simulation environment, and the hardware-in-the-loop simulation test and flight test were carried out to verify the performance of the method in the real environment. The experimental results show that the proposed method can achieve the optimal estimation of navigation parameters for simple guided ammunition with large-scale difference tail control. Under the conditions of simulation test and hardware-in-loop simulation test, the position and velocity errors calculated by the method in this paper converged. Under the condition of flight test, the spatial average error calculated by the method described in this paper is 6.17 m, and the spatial error of the final landing point is 3.50 *** this method, the accurate acquisition of navigation parameters in the process of projectile launching is effectively realized.

关键词： Guided projectiles Tail spin reduction RPM constraints Combined navigation Extended Kalman filter(EKF)

How to Construct a Lower Risk FOF Based on Correlation Network? The Method of Principal Component Risk Parity Asset Allocation

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Journal of Systems Science & Complexity 2024年第3期37卷 1052-1079页

作者： BAI Wei ZHANG Junting liu Haifei liu kai School of Management and Engineering Nanjing UniversityNanjing 210093China Postdoctoral Workstation of Bank of Jiangsu Co. LtdNanjing 210006China College of Finance Nanjing Agricultural UniversityNanjing 210095China University of Prince Edward Island 550 University AveCharlottetownPE C1A4P3Canada

In order to build a low-risk Fund of Funds(FOF), from the perspective of correlation, the principal component factor is used to improve the traditional risk parity model. Principal component analysis is used to decompose the underlying assets and generate unrelated principal component factors,and then the authors can construct a principal component risk parity portfolio. The proposed empirical results based on China’s mutual fund market show that the performance of principal component risk parity portfolio(PCRPP) is better than that of equal weight portfolio(EWP) and traditional risk parity portfolio(RPP). That is to say, not only the PCRPP in this paper has much lower risk than EWP and RPP, but also slightly better than EWP and RPP in terms of average return. Moreover, the study of dividing the underlying assets shows that the PCRPP in this paper is not sensitive to the underlying assets. The PCRPP in this paper is better than EWP and RPP for both the better performing funds and the worse performing funds. In addition, the empirical results on dynamic portfolio adjustments show that it is not appropriate to adjust asset allocation too frequently when the expected rate of return is calculated using the arithmetic mean.

关键词： Fund of funds(FOF) mutual funds portfolio risk principal component analysis risk parity portfolio

Lanthanide-based microlasers:Synthesis,structures,and biomedical applications

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Nano Research 2024年第1期17卷 97-111页

作者： Qian Zhang Yawei liu kai liu Hongjie Zhang Engineering Research Center of Advanced Rare Earth Materials(Ministry of Education) Department of ChemistryTsinghua UniversityBeijing 100084China State Key Laboratory of Rare Earth Resource Utilization Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China Xiangfu Laboratory Jiaxing 314102China

The large size of lasers limits their applications in confined spaces,such as in biosensing and in vivo brain tissue *** this regard,micron-sized lasers have been *** exhibit great potential for biological detecting,remote sensing,and depth tracking due to their small sizes,sensitive properties of their spectral fingerprints,and flexible positional modulation in the ***-based luminescent materials that possess long excited-state lifetime,narrow emission bandwidth,and upconversion behaviors are promising as gain mediums for novel *** addition,lanthanide-based microlasers could be generated under natural ambient conditions with pumped or continuous light sources,which significantly promotes the practical applications of *** progress in the design,synthesis,and biomedical applications of lanthanide-based microlasers has been outlined in this *** ions doped and upconverted lanthanide-based microlasers are highlighted,which exhibit advantageous structures,miniaturized dimensions,and high lasing *** applications of lanthanide-based microlasers are further discussed,the upconverted microlasers show great advantages for biological applications owing to their tunable excitation and emission characteristics and excellent environmental ***,perspectives and challenges in the field of lanthanide-based microlasers are presented.

关键词： microlasers lanthanide-based luminescent materials upconversion nanoparticles biological applications