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Consequences of redefining Alzheimer's disease in terms of amyloid burden without regard to cognitive decline 被引量:1
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作者 Stephen R.Robinson Holly M.Brothers Maya L.Gosztyla 《Neural Regeneration Research》 SCIE CAS CSCD 2018年第12期2098-2099,共2页
Alzheimer's disease(AD)redefined:For the past century,AD has been defined as a disease of progressive cognitive decline paired with a burden of amyloid-β(Aβ)plaques and pathologic tau tangles in the hippocampu... Alzheimer's disease(AD)redefined:For the past century,AD has been defined as a disease of progressive cognitive decline paired with a burden of amyloid-β(Aβ)plaques and pathologic tau tangles in the hippocampus and forebrain.However,a recent Framework paper jointly sponsored by the National Institute on Aging and the Alzheimer's Association(Jack et al.,2018)proposes new classification guidelines for AD,which,if adopted,will have profoundconsequences for the future management of AD. 展开更多
关键词 AD Consequences of redefining Alzheimer’s disease in terms of amyloid burden without regard to cognitive decline
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A STUDY ON THE INTERACTION BETWEEN CH_3OH AND H_2CO MOLECULES IN TERMS OF THE PROPERTIES OF CHARGE DENSITY DISTRIBUTIONS
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作者 Wei Liang CAO Jing Chang ZHANG Beijing Institute of Chemical Technology Beijing China 100029Xiao Yuan FU Beijing Normal University Beijing China 100875 《Chinese Chemical Letters》 SCIE CAS CSCD 1991年第7期571-574,共4页
Two possible complexes formed by the interaction of CH_3OH and H_2CO,one hydrogen-bonded (Ⅰ)and one donor-acceptor complex(Ⅱ),have been reported in the previous paper.Based on the ab initio 6-31G basis set calculati... Two possible complexes formed by the interaction of CH_3OH and H_2CO,one hydrogen-bonded (Ⅰ)and one donor-acceptor complex(Ⅱ),have been reported in the previous paper.Based on the ab initio 6-31G basis set calculations,the properties of the charge density for the complexeshave been analyzed using the theory of atoms in molecules.The nature of the complex formation has been discussed in terms of the properties of the charge density distributions. 展开更多
关键词 OH A STUDY ON THE inTERACTION BETWEEN CH3OH AND H2CO MOLECULES in terms of THE PROPERTIES of CHARGE DENSITY DISTRIBUTIONS CH CO
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A Comparative Study Of New Criticism&Semiotic Criticism——In Terms Of Their View Of The Relationship Between The Fictional World&The Real World
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作者 Chen Hong-Qin 《宜宾学院学报》 1997年第4期53-57,共5页
As we know,new criticism is the post—world school of critical theory insists onthe intrinsic value of work of art and focusses on the individual work alone asan independent unit of meaning.It is opposed to the critic... As we know,new criticism is the post—world school of critical theory insists onthe intrinsic value of work of art and focusses on the individual work alone asan independent unit of meaning.It is opposed to the critical practice of bringing histori-cal of brographical data to bear on the anterpretation of a work.To the new critocs,poet-.ry was a special kind of discourse,a means of communicating feeling and thought thatwould not be expressed in any other kind of language.It differed qualitatively from thelanguage of science,or philosophy,but it converyed valid meanings.Such critics set outto define and formalize the qualities of poetic thought and languagege,using the techniqueof close reading with special emphasis on the implicative values of works and on the vari-ous function of figurative language—imagery,metaphor and symbol—in the work. 展开更多
关键词 World A Comparative Study of New Criticism&Semiotic Criticism VIEW in terms of Their View of The Relationship Between The Fictional World&The Real World
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A novel chromatic dispersion monitoring method in terms of SO A spectral shift 被引量:1
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作者 石颖 陈明华 谢世钟 《Chinese Optics Letters》 SCIE EI CAS CSCD 2003年第7期383-384,共2页
In this paper a novel low power online chromatic dispersion (CD) monitoring method is presented, which employs spectral shift in the semiconductor optical amplifier (SOA). The advantage of this method lies in that the... In this paper a novel low power online chromatic dispersion (CD) monitoring method is presented, which employs spectral shift in the semiconductor optical amplifier (SOA). The advantage of this method lies in that the required input power can be much reduced, and the filter output can be used in the dynamic CD compensation system. The simulation indicates that the filtered power decreases with CD increases, and that the monitoring range increases as the filter bandwidth increases. 展开更多
关键词 of that or SOA in A novel chromatic dispersion monitoring method in terms of SO A spectral shift
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On the certain semi-analytical models of low-frequency acoustic fields in terms of scalar-vector description 被引量:13
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作者 OlegE.Gulin YangDesen 《Chinese Journal of Acoustics》 2004年第1期58-70,共13页
Behaviour of scalar and vector characteristics of steady-state acoustical field is modeled based on analytical-numerical approach. This field is radiated by low-frequency monochromatic point-like source in the determi... Behaviour of scalar and vector characteristics of steady-state acoustical field is modeled based on analytical-numerical approach. This field is radiated by low-frequency monochromatic point-like source in the deterministic layered shallow sea, which has various hydrologic and bottom conditions. Approach being developed is free of any mathematical approximations and without the difficulties it enables to calculate sound field vector characteristics for various 展开更多
关键词 On the certain semi-analytical models of low-frequency acoustic fields in terms of scalar-vector description
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BOUNDEDNESS IN TERMS OF TWO MEASURES FOR IMPULSIVE DISCRETE SYSTEMS 被引量:1
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作者 Wu Haixia (College of Mathematics and Computer Science, Hebei University, Baoding 071002} Wang Peiguang (College of Electronic and Information Engineering, Hebei University, Baoding 071002) 《Annals of Differential Equations》 2006年第3期384-387,共4页
This paper concerns a class of impulsive discrete systems and offers sufficient conditions of boundedness in terms of two measures for such systems, by employing vector Lyapunov functions and a new comparison principl... This paper concerns a class of impulsive discrete systems and offers sufficient conditions of boundedness in terms of two measures for such systems, by employing vector Lyapunov functions and a new comparison principle. The result obtained generalizes those in known literatures. 展开更多
关键词 impulsive discrete systems boundedness in terms of two measures vector Lyapunov functions comparison principle upper quasi-monotone
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Razumikhin Type Boundedness Theorems in Terms of Two Measures for Impulsive Integro-differential Systems
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作者 Zhuo-ying L Yan-Lin ZHENG Lai-liang ZHANG 《Acta Mathematicae Applicatae Sinica》 SCIE CSCD 2014年第4期1007-1016,共10页
Some new direct criteria of boundedness in terms of two measures for impulsive integro-differential systems with fixed moments of impulse effects are established by Lyapunov functions coupled with Razumikhin techniques.
关键词 impulsive integro-differential system Lyapunov function boundedness in terms of two measures
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An Overvie w of Acupuncture Research in Terms of Modern Me dicine
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作者 贾少微 王凡 黄海龙 《Chinese Journal of Integrative Medicine》 SCIE CAS 2001年第1期75-80,共6页
关键词 An Overvie w of Acupuncture Research in terms of Modern Me dicine
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A description of nitrogen-nitrogen bond in terms of charge distributions 被引量:1
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作者 CAO Wei-Liang MARSHALL T.C. BADER R.F.W. 《Chinese Journal of Chemistry》 SCIE CAS CSCD 1990年第6期492-506,共0页
A theoretical analysis of properties of the shared interactions between two neighbouring nitrogen atoms in a variety of compounds is presented, based on properties of charge distributions derived from 6-31 ++G** wave ... A theoretical analysis of properties of the shared interactions between two neighbouring nitrogen atoms in a variety of compounds is presented, based on properties of charge distributions derived from 6-31 ++G** wave functions. Bond is characterized in terms of its bond order, bond ellipticity and the quantity of Laplacian of p at the bond critical point. The difference between the bond path angle and the corresponding geometrical angle provides a measure of the degree of relaxation for the charge density away from the geometrical constraints imposed by the nuclear framework. Comparisons have been made between the nitrogen-containing compounds and isoelectronic hydrocarbons. Values of the NN bond energies, based on the properties of NN bond interatomic surface, are determined in three schemes. 展开更多
关键词 NN A description of nitrogen-nitrogen bond in terms of charge distributions
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Coupling dynamic analysis of spacecraft with multiple cylindrical tanks and flexible appendages 被引量:5
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作者 Wen-Jun Wu Bao-Zeng Yue Hua Huang 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2016年第1期144-155,共12页
This paper is mainly concerned with the coupling dynamic analysis of a complex spacecraft consisting of one main rigid platform, multiple liquid-filled cylindrical tanks, and a number of flexible appendages. Firstly, ... This paper is mainly concerned with the coupling dynamic analysis of a complex spacecraft consisting of one main rigid platform, multiple liquid-filled cylindrical tanks, and a number of flexible appendages. Firstly, the carrier potential function equations of liquid in the tanks are deduced according to the wall boundary conditions. Through employ- ing the Fourier-Bessel series expansion method, the dynamic boundaries conditions on a curved free-surface under a low-gravity environment are transformed to general simple differential equations and the rigid-liquid coupled sloshing dynamic state equations of liquid in tanks are obtained. The state vectors of rigid-liquid coupled equations are composed with the modal coordinates of the relative potential func- tion and the modal coordinates of wave height. Based on the B ernoulli-Euler beam theory and the D'Alembert's prin- ciple, the rigid-flexible coupled dynamic state equations of flexible appendages are directly derived, and the coordi- nate transform matrixes of maneuvering flexible appendages are precisely computed as time-varying. Then, the cou- pling dynamics state equations of the overall system of the spacecraft are modularly built by means of the Lagrange's equations in terms of quasi-coordinates. Lastly, the cou-piing dynamic performances of a typical complex spacecraft are studied. The availability and reliability of the presented method are also confirmed. 展开更多
关键词 Multiple liquid-filled cylindrical tanks TheFourier-Bessel series expansion method Low-gravityenvironment Maneuvering flexible appendages TheLagrange's equations in terms of quasi-coordinates
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A study on physical property of crustal material and seismogenic environment in northeastern Pamir 被引量:2
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作者 刘志 张先康 +3 位作者 周雪松 赵金仁 张成科 潘纪顺 《Acta Seismologica Sinica(English Edition)》 CSCD 2003年第3期251-259,共9页
2-D crustal structure and velocity ratio are obtained by processing S-wave data from two wide-angle reflec-tion/refraction profiles in and around Jiashi in northeastern Pamir, with the result of P-wave data taken into... 2-D crustal structure and velocity ratio are obtained by processing S-wave data from two wide-angle reflec-tion/refraction profiles in and around Jiashi in northeastern Pamir, with the result of P-wave data taken into con-sideration. The result shows that: 1) Average crustal velocity ratio is obviously higher in Tarim block than in West Kunlun Mts. and Tianshan fold zone, which reflects its crustal physical property of 'hardness' and stability. The relatively low but normai velocity ratio (Poisson's ratio) of the lower crust indicates that the 'downward thrusting' of Tarim basin is the main feature of crustal movement in this area. 2) The rock layer in the upper crust of Tianshan fold zone is relatively 'soft', which makes it prone to rupture and stress energy release. This is the primary tectonic factor for the concentration of small earthquakes in this area. 3) Jiashi is located right over the apex or the inflection point of the updoming lower crustal interface C and the crust-mantle boundary, which is the deep struc-tural background for the occurrence of strong earthquakes. The alternate variation of vp/vs near the block bounda-ries and the complicated configuration of the interfaces in the upper and middie part of the upper crust form a par-ticular structural environment for the Jiashi strong earthquake swarm. vp/vs is comparatively high and shear modulus is low at the focal region, which may be the main reason for the low stress drop of the Jiashi strong earthquake swarm. 展开更多
关键词 northeastern Pamirs crustal structure in terms of physical property Jiashi strong earthquake swarm velocity ratio
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From Hölder Continuous Solutions of 3D Incompressible Navier-Stokes Equations to No-Finite Time Blowup on [ 0,∞ ]
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作者 Terry E. Moschandreou 《Advances in Pure Mathematics》 2024年第9期695-743,共49页
This article gives a general model using specific periodic special functions, that is, degenerate elliptic Weierstrass P functions composed with the LambertW function, whose presence in the governing equations through... This article gives a general model using specific periodic special functions, that is, degenerate elliptic Weierstrass P functions composed with the LambertW function, whose presence in the governing equations through the forcing terms simplify the periodic Navier Stokes equations (PNS) at the centers of arbitrary r balls of the 3-Torus. The continuity equation is satisfied together with spatially periodic boundary conditions. The yicomponent forcing terms consist of a function F as part of its expression that is arbitrarily small in an r ball where it is associated with a singular forcing expression both for inviscid and viscous cases. As a result, a significant simplification occurs with a v3(vifor all velocity components) only governing PDE resulting. The extension of three restricted subspaces in each of the principal directions in the Cartesian plane is shown as the Cartesian product ℋ=Jx,t×Jy,t×Jz,t. On each of these subspaces vi,i=1,2,3is continuous and there exists a linear independent subspace associated with the argument of the W function. Here the 3-Torus is built up from each compact segment of length 2R on each of the axes on the 3 principal directions x, y, and z. The form of the scaled velocities for non zero scaled δis related to the definition of the W function such that e−W(ξ)=W(ξ)ξwhere ξdepends on t and proportional to δ→0for infinite time t. The ratio Wξis equal to 1, making the limit δ→0finite and well defined. Considering r balls where the function F=(x−ai)2+(y−bi)2+(z−ci)2−ηset equal to −1e+rwhere r>0. is such that the forcing is singular at every distance r of centres of cubes each containing an r-ball. At the centre of the balls, the forcing is infinite. The main idea is that a system of singular initial value problems with infinite forcing is to be solved for where the velocities are shown to be locally Hölder continuous. It is proven that the limit of these singular problems shifts the finite time blowup time ti∗for first and higher derivatives to t=∞thereby indicating that there is no finite time blowup. Results in the literature can provide a systematic approach to study both large space and time behaviour for singular solutions to the Navier Stokes equations. Among the references, it has been shown that mathematical tools can be applied to study the asymptotic properties of solutions. 展开更多
关键词 Navier-Stokes Periodic Navier-Stokes Equations 3-Torus Periodic Ball Sphere Hölder Continuous Functions Uniqueness Angular Velocity Velocity in terms of Vorticity
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Strain-induced ferroelectric phase transitions in incipient ferroelectric rutile TiO_2
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作者 倪利红 刘涌 +2 位作者 任召辉 宋晨路 韩高荣 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第10期335-339,共5页
Uniaxial strain induced ferroelectric phase transitions in rutile TiO2 are investigated by first-principles calculations. The calculated results show that the in-plane tensile strain induces rutile TiO2, paraelectric ... Uniaxial strain induced ferroelectric phase transitions in rutile TiO2 are investigated by first-principles calculations. The calculated results show that the in-plane tensile strain induces rutile TiO2, paraelectric phase with P4-2/mnm (D4h) space group, to a ferroelectric phase with Pm(Cs) space group, driven by the softening behaviour of the Eul mode. In addition, the out-of-plane tensile strain, vertical to the ab plane, leads to a ferroelectric phase with P42nm (C4v) space group, driven by the softening behaviour of the A2u mode. The critical tensile strains are 3.7% in-plane and 4.0% out-of-plane, respectively. In addition, the in-plane compression strain, which has the same structure variation as out- of-plane tensile strain due to Poisson effect, leads the paraelectric rutile TiO2 to a paraelectric phase with Pnnm (D2h) space group driven by the softening behaviour of the B1g mode. These results indicate that the sequence ferroelectric (or paraelectric) phase depends on the strain applied. The origin of ferroelectric stabilization in rutile TiO2 is also discussed briefly in terms of strain induced Born effective charge transfer. 展开更多
关键词 briefly in terms of strain induced Born effective charge transfer.
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