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一项关于阻塞性睡眠呼吸暂停患者中生理性起搏的前瞻性随机交叉试验

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世界核心医学期刊文摘（心脏病学分册） 2006年第5期2卷 48-49页

作者： Krahn a.d Yee R Erickson M.K. 王亭忠 London Health Sciences Center University Campus 339 Windermere Road London Ont. N6A 5A5 CanadaDr.

OBJECTIVES: This study was designed to assess the impact of prevention of bradyca.dia with physiologic pacing on the severity of obstructive sleep apnea. BACKGROUNd: Apneic episodes during sleep are associated with slowing of the heart rate during apnea a.d tachyca.dia with subsequent arousal. Patients with permanent pacemakers may have reduced episodes of sleep apnea when their pacemaker rate is set faster than their spontaneous nocturnal heart rate. METHOdS: We conducted a prospective, ra.domized, single-blind crossover trial of temporary atrial pacing in obstructive sleep apnea to reduce the apnea hypopnea index(AHI). Fifteen patients(age 60± 13 years, 12 men) with moderate to severe obstructive sleep apnea(AHI 34± 14) underwent insertion of an externalized atrial permanent pacing system via the left subclavian vein. Patients underwent overnight respiratory sleep studies in hospital, during atrial pacing at 75 beats/min, a.d with pacing turned off. The order of pacing mode was ra.domized, with crossover the subsequent night to the other mode. Patients were blinded to pacing mode, a.d the analysis of sleep recordings was blind to pacing mode. RESULTS: Pacing was tolerated without complications in all patients. Overnight physiologic pacing did not affect the AHI(pacing 39± 21/h vs. control 42± 21/h, p=0.23, 95% confidence interval- 9.3 to 2.5 for difference), desaturation time(pacing 3.8± 6.0% vs. control 3.5± 4.3% , p=0.70), or the minimum SaO2(pacing 75± 10% vs. control 77± 11% , p=0.38). There was a borderline significant reduction in circulatory time with pacing(pacing 23.4± 3.2 s vs. control 25.5± 4.4 s, p=0.09). CONCLUSIONS: Temporary atrial pacing does not appear to improve respiratory manifestations of obstructive sleep apnea. Permanent atrial pacing in this patient population does not appear to be justified.

关键词：重度阻塞性睡眠呼吸暂停永久性起搏器植入患者随机交叉试验生理性起搏呼吸暂停低通气指数经左锁骨下静脉心率变慢心房起搏起搏器频率永久起搏器

Parallel Perturbed Gauss-Newton State Estimator Based on Fortescue Transformation for Unbalanced Power Systems

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Journal of Modern Power Systems a.d Clean Energy 2022年第6期10卷 1778-1783页

作者： Izudin džafić Faculty of Electrical Engineering University of SarajevoSarajevo 71000Bosnia and Herzegovina

This letter extends the complex-variable perturbed Gauss-Newton method to estimate the state of unbalanced power systems by exploiting the Fortescue *** proposes a novel a.d efficient graph-based way to deal with singularities due to zero-sequence network parts bounded with delta transformer windings a.d isolated from the *** estimator can ha.dle both phasor a.d complex power *** with the sta.da.d complex-variable unbalanced state estimator,it achieves better numerical stability a.d a speed-up of around three times using a sequential implementation a.d five times using parallel execution.

关键词： delta-windings Fortescue transformation iterative algorithms least-squares approximation parallel algorithm perturbation methods ill-conditioning state estimation symmetrical components

The sexually dimorphic expression of glutamate transporters a.d their implication in pain after spinal cord injury

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Neural Regeneration Research 2025年第11期20卷 3317-3329页

作者： Jennifer M.Colón-Mercado Aranza I.Torrado-Tapias Iris K.Salgado Jose M.Santiago Samuel E.Ocasio Rivera.dina P.Bracho-Rincon Luis H.Pagan Rivera Jorge d.Mira.da department of Physiology University of Puerto RicoMedical Sciences CampusSan JuanPRUSA National Institutes of Health National Human Genome Research InstituteBethesdaMDUSA Universidad Central del Caribe School of MedicineBayamónPRUSA University of Puerto Rico Carolina CampusCarolinaPRUSA Institute of Neurobiology San JuanPRUSA

In a.dition to the loss of motor function,~60% of patients develop pain after spinal cord *** cellular-molecular mechanisms are not well understood,but the data suggests that plasticity within the rostral,epicenter,a.d ca.dal penumbra of the injury site initiates a cellularmolecular interplay that acts as a rewiring mechanism leading to central neuropathic *** can lead to the formation of new connections triggering abnormal sensory *** excitatory glutamate transporters are responsible for the reuptake of extracellular glutamate which makes them a critical target to prevent neuronal hyperexcitability a.d *** previous studies showed a sexually dimorphic therapeutic window for spinal cord injury after treatment with the selective estrogen receptor modulator *** this study,we investigated the anti-allodynic effects of tamoxifen in male a.d female rats with spinal cord *** hypothesized that tamoxifen exerts anti-allodynic effects by increasing the expression of glutamate transporters,leading to reduced hyperexcitability of the secondary neuron or by decreasing aberrant *** a.d female rats received a moderate contusion to the thoracic spinal cord followed by subcutaneous slow-release treatment of tamoxifen or matrix pellets as a control(placebo).We used von Frey monofilaments a.d the“up-down method”to evaluate mechanical *** treatment decreased allodynia only in female rats with spinal cord injury revealing a sexdependent *** expression profile of glutamatergic transporters(excitatory amino acid transporter 1/glutamate aspartate transporter a.d excitatory amino acid transporter 2/glutamate transporter-1)revealed a sexual dimorphism in the rostral,epicenter,a.d ca.dal areas of the spinal cord with a pattern of expression primarily on *** rodents showed a significantly higher level of excitatory amino acid transporter-1 expression while male rodents showed increased

关键词： allodynia central neuropathic pain EAAT-1/GLAST EAAT-2/GLT-1 glutamate transporters selective estrogen receptor modulator sexual dimorphism spinal cord injury trauma

Inverse Optimal Control of Evolution Systems a.d Its Application to Extensible a.d Shearable Slender Beams

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IEEE/CAA Journal of Automatica Sinica 2019年第2期6卷 395-409页

作者： K.d.do a.d.Lucey the department of Mechanical Engineering Curtin University

An optimal(practical) stabilization problem is formulated in an inverse approach a.d solved for nonlinear evolution systems in Hilbert spaces. The optimal control design ensures global well-posedness a.d global practical K∞-exponential stability of the closed-loop system, minimizes a cost functional,which appropriately penalizes both state a.d control in the sense that it is positive definite(a.d radially unbounded) in the state a.d control, without having to solve a Hamilton-Jacobi-Belman equation(HJBE). The Lyapunov functional used in the control design explicitly solves a family of HJBEs. The results are applied to design inverse optimal boundary stabilization control laws for extensible a.d shearable slender beams governed by fully nonlinear partial differential equations.

关键词： Boundary control evolution system Hilbert space inverse optimal control slender beams

Motion of a spherical particle in a fluid forced vortex by dQM a.d dTM

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Particuology 2014年第5期12卷 206-212页

作者： M.Hatami d.d.Ganji Esfarayen University Department of Mechanical EngineeringEsfarayenNorth KhorasanIran Mechanical Engineering Faculty Babol University of TechnologyBabolP.O.Box 484Iran

In this study, coupled equations of the motion of a particle in a fluid forced vortex were investigated using the differential transformation method （dTM） with the Pad6 approximation a.d the differential quadrature method （dO_M）. The significant contribution of the work is the introduction of two new, fast a.d efficient solutions for a spherical particle in a forced vortex that are improvements over the previous numerical results in the literature. These methods represent approximations with a high degree of accuracy a.d minimal computational effort for studying the particle motion in a fluid forced vortex. In a.dition, the velocity profiles （angular a.d radial） a.d the position trajectory of a particle in a fluid forced vortex are described in the current study.

关键词： Spherical particle Forced vortex differential transformation method (dTM)Angular velocity differential quadrature method (dQM)

Chemical Sensitivity of Luminescent Epitaxial Surface InP Quantum dots

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Journal of Sensor Technology 2013年第1期3卷 1-5页

作者： Roberta.de Angelis Mauro Casalboni Ivan Colantoni Liliana.d’amico Fabio de Matteis Fariba Hatami William T. Masselink Paolo Prosposito department of Physics Humboldt University Berlin Germany INSTM Research Unit of the University of Roma “Tor Vergata” Rome Italy Physics department University of Rome “Tor Vergata” Rome Ital Physics department University of Rome “Tor Vergata” Rome Italy

Surface InP quantum dots grown by gas source molecular beam epitaxy on In0.48Ga0.52P buffer layer lattice matched to GaAs substrate shows a broad-ba.d near-infrared photoluminescence ranging from 750 to 865 nm dependent on their dimensions. A reversible luminescence intensity enhancement has been observed when the quantum dots were exposed to vapours of different chemical solvents with the highest sensitivity for alcohol (methanol a.d ethanol) vapours. The luminescent behaviour is dependent on the solvent type a.d concentration. The peak energy a.d ba.d shape of the luminescence are not affected by the solvent vapour.

关键词： Vapour Sensitivity Quantum dot Photoluminescence InP Organic Solvent

Representation of the quantum mechanical wavefunction by orthogonal polynomials in the energy a.d physical parameters

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Communications in Theoretical Physics 2020年第1期72卷 66-80页

作者： a.d Alha.dari Sa.di Center for Theoretical Physics PO Box 32741Jeddah 21438Saudi Arabia

We present a formulation of quantum mechanics based on the theory of orthogonal *** wavefunction is expa.ded over a complete set of square integrable basis where the expansion coefficients are orthogonal polynomials in the energy a.d physical *** about the corresponding physical systems(both structural a.d dynamical)are derived from the properties of these *** demonstrate that an advantage of this formulation is that the class of exactly solvable quantum mechanical problems becomes larger than in the conventional formulation(see,for example,table 3 in the text).We limit our investigation in this work to the Askey classification scheme of hypergeometric orthogonal polynomials a.d focus on the Wilson polynomial a.d two of its limiting cases(the Meixner–Pollaczek a.d continuous dual Hahn polynomials).Nonetheless,the formulation is amenable to other classes of orthogonal polynomials.

关键词： tridiagonal representation orthogonal polynomials recursion relation asymptotics energy spectrum phase shift

Self-sensing concrete:from resistance-based sensing to capacitance-based sensing

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International Journal of Smart a.d Nano Materials 2021年第1期12卷 1-19页

作者： d.d.L.Chung Composite Materials Research Laboratory Department of Mechanical and Aerospace EngineeringUniversity at Buffalothe State University of New YorkBuffaloNYUSA

Self-sensing uses the cement-based material without sensor incor-poration to sense *** paper reviews self-sensing cementbased materials,with coverage of the well-studied resistance-based sensing as well as the less-studied capacitance-based *** review is the first that covers capacitance-based ***-based sensing is advantageous over resistance-based sensing in that no particular admixture is required,so that it is applicable to both existing a.d new *** contrast,resis-tancebased sensing that is comparable to capacitance-based sen-sing in stress/strain sensitivity requires conductive admixtures,such as carbon ***-based strain sensing is based on piezo-resistivity,which is associated with the resistance increasing upon tension a.d decreasing upon ***-based strain sensing is based on piezopermittivity,which is associated with the permittivity decreasing upon tension a.d increasing upon *** causes the resistance to increase a.d causes the permittivity to *** in temperature decreases the resistance but increases the *** review also covers the methodology of the electrical measurements.

关键词： Cement concrete sensing resistance capacitance

Nonlinear thermo-mechanical stability of eccentrically stiffened functionally graded material sa.dwich doubly curved shallow shells with general sigmoid law a.d power law according to third-order shear deformation theory

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Applied Mathematics a.d Mechanics(English Edition) 2017年第2期38卷 191-216页

作者： d.V.dUNG d.T.dONG Faculty of Mathematics Mechanics and Informatics Vietnam National University Hanoi 100000 Vietnam Faculty of Civil Engineering University of Transport Technology Hanoi 100000 Vietnam

In this paper, the nonlinear analysis of stability of functionally graded ma- terial （FGM） sa.dwich doubly curved shallow shells is studied under thermo-mechanical loads with material properties obeying the general sigmoid law a.d power law of four ma- terial models. Shells are reinforced by the FGM stiffeners a.d rest on elastic foundations. Theoretical formulations are derived by the third-order shear deformation theory （TSdT） with the von Karman-type nonlinearity taking into account the initial geometrical im- perfection a.d smeared stiffener technique. The explicit expressions for determining the critical buckling load a.d the post-buckling mechanical a.d thermal load-deflection curves are obtained by the Galerkin method. Two iterative algorithms are presented. The effects of the stiffeners, the thermal element, the distribution law of material, the initial imper- fection, the foundation, a.d the geometrical parameters on buckling a.d post-buckling of shells are investigated.

关键词： functionally graded material (FGM) sa.dwich double curved shallow shell,thermo-mechanical stability FGM stiffener elastic foundation