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Conformational dynamics as an intrinsic determinant of prion protein misfolding and neurotoxicity
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作者 Alessandro Cembran Pedro Fernandez-Funez 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第10期2095-2096,共2页
The prion protein(PrP) is the key molecular and pathological mediator of prion diseases,a heterogeneous group of brain disorders with fatal outcomes.Prion diseases are rare but deserve special attention because of the... The prion protein(PrP) is the key molecular and pathological mediator of prion diseases,a heterogeneous group of brain disorders with fatal outcomes.Prion diseases are rare but deserve special attention because of their unique familial,sporadic,and transmissible etiologies,all caused by a single agent:misfolded conformations of PrP. 展开更多
关键词 FOLDING intrinsic DYNAMICS
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Intrinsic and scattering attenuations of the Sichuan-Yunnan region in China from S coda waves
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作者 Tian Li Lei Zhang +4 位作者 Xiaodong Song Qincai Wang Xinyu Jiang Jinchuan Zhang Hanlin Chen 《Earthquake Science》 2024年第1期51-66,共16页
Seismic attenuation is a fundamental property of the Earth's media.Attenuation structure for the complicated geological structures with strong seismicity in the Sichuan-Yunnan region is poorly studied.In this stud... Seismic attenuation is a fundamental property of the Earth's media.Attenuation structure for the complicated geological structures with strong seismicity in the Sichuan-Yunnan region is poorly studied.In this study,we collected 108,399 waveforms of 11,517 local small earthquakes with magnitudes between 1.5 and 3.5 from January 2014 to September 2021 in the Sichuan-Yunnan region and its adjacent areas.We employed an envelope inversion technique for separating the intrinsic and scattering attenuations of the S coda wave,and obtained the intrinsic and scattering attenuation structures for frequencies between 0.25 and 8.00 Hz.The attenuation structures correlate well with the geological units,and some major faults mark the attenuation variations where historic large earthquakes have occurred.The regional average attenuation shows a negative frequency dependence.The average scattering attenuation has a faster descending rate than the average intrinsic attenuation,and is dominant at low frequencies,while at high frequencies the average intrinsic attenuation is stronger.The lateral variation in the intrinsic attenuation is consistent with the variation in heat flow,the scattering attenuation may be related to the scatter distribution and size.The total attenuation is consistent with the previous studies in this region,and the separate intrinsic and scattering attenuation may be useful in understanding regional tectonics and important in earthquake prevention and disaster reduction. 展开更多
关键词 intrinsic attenuation scattering attenuation Sichuan-Yunnan region
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Linearization of Intrinsically Nonlinear Oscillators
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作者 Pirooz Mohazzabi Qinghua Luo Ilirian Dhimitruka 《Journal of Applied Mathematics and Physics》 2024年第8期2829-2835,共7页
We show that an intrinsically nonlinear oscillator can always be transformed into a linear or harmonic oscillator by addition of a constant force, which shifts the equilibrium position of the oscillator.
关键词 intrinsic NONLINEAR OSCILLATOR LINEARIZATION
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Experimental Study of the Influence of Intrinsic Parameters on the Thermal Reactivity of Sawdust, Polyethylene Terephthalate and Composite
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作者 Ange Brel Boukongou Timoléon Andzi Barhé 《Journal of Materials Science and Chemical Engineering》 2024年第3期9-20,共12页
Several works have been based on the study of thermal variations in biomass to derive more valuable products such as fuels capable of replacing oil in the event of a crisis or activated carbon used as an adsorbent mat... Several works have been based on the study of thermal variations in biomass to derive more valuable products such as fuels capable of replacing oil in the event of a crisis or activated carbon used as an adsorbent material, widely used in industry for the elimination of unwanted materials, both in liquid and gaseous environments. A study of thermal parameters such as: heating speed, retention time, drying temperature, carbonization temperature, particle size, was carried out with the aim of determining the characteristic factors of the carbonization of Polyethylene terephthalate (PET), sawdust (SC) and sawdust/polyethylene terephthalate (CPS) mixture. The results of the immediate analysis revealed a very low level of ash in PET (0.013%) compared to the level of ash in sawdust (2.9%), as well as a high level of fixed carbon (82.960%), which suggests the presence of mineral oxides and a significant carbon matrix unlike PET, which indicates a very significant organic matrix (essentially made up of organic matter) with the absence of mineral oxides. The study of thermal parameters showed the water loss from Sawdust (SC) and the Sawdust/Polyethylene terephthalate (CPS) mixture, an increase with temperature, unlike that of PET whose variation is essentially zero. Without heat treatment, sawdust alone contains approximately 7% water. The optimal drying temperature for this study is 110˚C for a stay of 24 hours. It appears that the largest mass losses for the PET samples are between 87.19% and 96.05%, followed by that of the mixture, between 47.33% and 64.37%. And the lowest are observed, those of sawdust (from 24.02% to 62.6%). However, here we can say that the influence of the mass is not great, given the slight difference between the losses by temperature. The results of the study of the influence of grain size showed that the differences are insignificant, even if we vary the diameter of the grains from simple to triple. To better minimize physical constraints such as the intragranular diffusibility of the volatile matter and the homogeneity of the temperature in the grains, 75 μm particles are found to be optimal for our study. It can be noted when studying the heating rate that the mass loss at the end of the reaction is approximately the same depending on each precursor material. However, it has been demonstrated that the heating rate strongly influences the nature of the reaction products both for volatile materials and for the solid residue as well as on the kinetic parameters of the chemical reaction. Furthermore, the variation in apparent density shows a decrease as a function of the increase in the residence time of the materials in the reactor. As the carbonization time increases, the apparent density decreases. We note, for the lignocellulosic material, that the apparent density stabilizes after 60 minutes. 展开更多
关键词 intrinsic Parameters Thermal Reactivity SAWDUST Polyethylene Terephthalate COMPOSITE
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A novel DPSS filter optimization scheme to reduce the intrinsic interference of FBMC-QAM systems
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作者 董琪阳 MA Tianming +1 位作者 JIN Jie WU Zhong 《High Technology Letters》 EI CAS 2024年第1期68-74,共7页
In order to reduce the intrinsic interference of the filter bank multicarrier-quadrature amplitude modulation(FBMC-QAM)system,a novel filter optimization scheme based on discrete prolate spheroidal sequences(DPSS)is p... In order to reduce the intrinsic interference of the filter bank multicarrier-quadrature amplitude modulation(FBMC-QAM)system,a novel filter optimization scheme based on discrete prolate spheroidal sequences(DPSS)is proposed.Firstly,a prototype filter function based on DPSS is designed,since the eigenvalue can be used as an indicator of the energy concentration of DPSS,so a threshold is set,and the sequence with the most concentrated energy is selected under the threshold,that is,the sequence with the eigenvalue higher than the threshold,and the prototype filter function is rewritten as a weighted sum function of multiple eigenvectors.Under the energy constraints of the filter,the relationship between the eigenvectors and the intrinsic interference function is established,and the function problem is transformed into an optimization problem for the weighted coefficients.Through the interior point method,the most suitable weight is found to obtain the minimum intrinsic interference result.Theoretical analysis and simulation results show that compared with the prototype filters such as Type1 and CaseC,the DPSS filter applying the proposed optimization algorithm can effectively suppress the intrinsic interference of the system and obtain a better bit error rate(BER)performance. 展开更多
关键词 filter bank multicarrier-quadrature amplitude modulation(FBMC-QAM) intrinsic interference discrete prolate spheroidal sequences(DPSS) interior point method
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Intrinsic Spin Angular Momentum of Electron Relation to the Discrete Indivisible Quantum of Time Kshana or Moment
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作者 Shesharao M. Wanjerkhede 《Journal of Modern Physics》 2024年第9期1337-1352,共16页
The frequency of any periodic event can be defined in terms of units of Time. Planck constructed a unit of time called the Plank time from other physical constants. Vyasa defined a natural unit of time, kshana, or mom... The frequency of any periodic event can be defined in terms of units of Time. Planck constructed a unit of time called the Plank time from other physical constants. Vyasa defined a natural unit of time, kshana, or moment based on the motion of a fundamental particle. It is the time taken by an elementary particle, to change its direction from east to north. According to Vyasa, kshana is discrete, exceedingly small, indivisible, and is a constant time quantum. When the intrinsic spin angular momentum of an electron was related to the angular momentum of a simple thin circular plate, spherical shell, and solid sphere model of an electron, we found that the value of kshana in seconds was equal to ten to a power of minus twenty-one second. The disc model for the spinning electron provides an accurate value of the number of kshanas per second as determined previously and compared with other spinning models of electrons. These results indicate that the disk-like model of spinning electrons is the correct model for electrons. Vyasa’s definition of kshana opens the possibility of a new foundation for the theory of physical time, and perspectives in theoretical and philosophical research. 展开更多
关键词 Natural Time Unit Quantum Time Kshana Plank Time intrinsic Angular Momentum Thin Disc Model Compton Wavelength
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Doped-Chamber Deposition of Intrinsic Microcrystalline Silicon Thin Films and Its Application in Solar Cells 被引量:1
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作者 孙福河 张晓丹 +9 位作者 赵颖 王世峰 韩晓艳 李贵军 魏长春 孙建 侯国付 张德坤 耿新华 熊绍珍 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2008年第5期855-858,共4页
A series of microcrystalline silicon thin films were fabricated by very high frequency plasma enhanced chemical vapor deposition (VHF-PECVD) at different silane concentrations in a P chamber. Through analysis of the... A series of microcrystalline silicon thin films were fabricated by very high frequency plasma enhanced chemical vapor deposition (VHF-PECVD) at different silane concentrations in a P chamber. Through analysis of the structural and electrical properties of these materials,we conclude that the photosensitivity slightly decreased then increased as the silane concentration increased,while the crystalline volume fraction indicates the opposite change. Results of XRD indicate that thin films have a (220) preferable orientation under certain conditions. Microcrystalline silicon solar cells with conversion efficiency 4. 7% and micromorph tandem solar cells 8.5% were fabricated by VHF-PECVD (p layer and i layer of microcrystalline silicon solar cells were deposited in P chamber), respectively. 展开更多
关键词 VHF-PECVD intrinsic microcrystalline silicon solar cells
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Construction analysis on integral lifting of steel structure by the vector form intrinsic finite element 被引量:2
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作者 朱明亮 陈雪琪 郭正兴 《Journal of Southeast University(English Edition)》 EI CAS 2016年第4期451-456,共6页
A newnumerical method based on vector form intrinsic finite element(VFIFE) is proposed to simulate the integral lifting process of steel structures. First, in order to verify the validity of the VFIFE method, taking... A newnumerical method based on vector form intrinsic finite element(VFIFE) is proposed to simulate the integral lifting process of steel structures. First, in order to verify the validity of the VFIFE method, taking the steel gallery between the integrated building and the attached building of Nanjing M obile Communication Buildings for example, the static analysis was carried out and the corresponding results were compared with the results achieved by the traditional finite element method. Then, according to the characteristics of dynamic construction of steel structure integral lifting, the tension cable element was employed to simulate the behavior of dynamic construction. The VFIFE method avoids the iterative solution of the stiffness matrix and the singularity problems. Therefore, it is simple to simulate the complete process of steel structure lifting construction.Finally, by using the VFIFE, the displacement and internal force time history curves of the steel structures under different lifting speeds are obtained. The results show that the lifting speed has influence on the lifting force, the internal force, and the displacement of the structure. In the case of normal lifting speed, the dynamic magnification factor of 1. 5 is safe and reasonable for practical application. 展开更多
关键词 integral lifting vector form intrinsic finite element(VFIFE) steel gallery whole process of construction dynamic magnification factor
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Relationships Between Average Molecular Mass and Intrinsic viscosity of Three Typical Polyanhydrides
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作者 帅心涛 谭惠民 王晓青 《Journal of Beijing Institute of Technology》 EI CAS 1998年第1期39-42,共4页
Aim To study the relationships between average molecular mass and intrinsic viscosity of polyanhydrides. Methods With chloroform as solvent and petroleum ether as the precipitating agent polyanhydride was separated in... Aim To study the relationships between average molecular mass and intrinsic viscosity of polyanhydrides. Methods With chloroform as solvent and petroleum ether as the precipitating agent polyanhydride was separated into a series of grades with different average molecular mass. The absolute average molecular mass (M) and intrinsic viscosity ([]) of every grade were measured. Results and Conclusion The relationships between [] and M of three typical polyanhydrides were obtained from bi-logarithm coordinate plotting of [] versus M. 展开更多
关键词 polanhydrides []-M relationship light scattering intrinsic viscosity
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APPLICATION OF WYATT-WHITE METHOD TO CALCULATING INTRINSIC RATES OF INCREASE FOR HYMENOPTEROUS PARASITOIDS
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作者 况荣平 Sandy M.Smith 《Zoological Research》 CAS CSCD 1993年第3期208-214,共7页
The method developed by Wyatt and White (1977) was applied to calculate the intrinsic rates of increase for parasitoids based on 23 fecundity data sets from the literature. The studies showed that there existed the li... The method developed by Wyatt and White (1977) was applied to calculate the intrinsic rates of increase for parasitoids based on 23 fecundity data sets from the literature. The studies showed that there existed the linear relationship between the accurate values of rm and In f (Md) / d or In (A/d/2) / d, that is, 1) rm= 0.845 In (Md) / d or 2) rm= 0.880 In (Md/ 2) / d. Where d is the prereproductive time, Md is the number of female offspring produced per original female from the first to the dthday of reproduction, and Md/2 is the number of female offspring produced per original female from the first to the (d/ 2) th day of reproduction. These equations can provide the accurate estimates of rm for parasitoids in this study. The approach is advantageous because it does not require the construction of detailed fecundity tables for estimating parasitoid rates of increase. Of course, whether these equations are appropriate for the other taxa will need to be further studied. 展开更多
关键词 PARASITOID intrinsic rate of increase Calculation
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Strategies on Enhancing Learners Intrinsic Motivation in Foreign Language Learning in the Context of China’s University
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作者 何啟滨 《语言与文化研究》 2010年第1期123-128,共6页
The paper aims to discuss the English learning situation of Chinese university students in the domain of motivation theory.With specific focus on enhancing learners’ intrinsic motivation, the paper analyzes the motiv... The paper aims to discuss the English learning situation of Chinese university students in the domain of motivation theory.With specific focus on enhancing learners’ intrinsic motivation, the paper analyzes the motivation orientation of Chinese university students and suggests four motivating strategies to promote students to become self - motivated learners. 展开更多
关键词 intrinsic MOTIVATION MOTIVATION ORIENTATION strate
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Stability of Difference Schemes with Intrinsic Parallelism for Quasilinear Parabolic Systems 被引量:10
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作者 Zhou Yulin and Yuan GuangweiLaboratory of Computational PhysicsCentre for Nonlinear Studies(Institute of Applied Physics and Computational MathematicsP. O. Box 8009, Boiling, 100088, China) 《Wuhan University Journal of Natural Sciences》 CAS 1996年第Z1期579-592,共14页
In this paper, the first boundary problem of quasilinear parabolic system of second order is studied by the finite difference method with intrinsic parallelism. for the problem, the stability of the difference schemes... In this paper, the first boundary problem of quasilinear parabolic system of second order is studied by the finite difference method with intrinsic parallelism. for the problem, the stability of the difference schemes with intrinsic parallelism are justified in the sense of the continuous dependence of the discrete vector solution of the difference schemes on the discrete data of the original problem, without assuming the existence of the smooth solutions for the origillal problem. 展开更多
关键词 Difference scheme intrinsic parallelism Quasilinear 'parabolic systems Stability.
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Comparison of Remolded Shear Strength with Intrinsic Strength Line for Dredged Deposits 被引量:9
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作者 邓东升 《China Ocean Engineering》 SCIE EI 2007年第2期363-369,共7页
Chandler proposed the intrinsic strength line to correlate the undrained shear strength of samples one-dimensionally consolidated from slurry with the void index proposed by Burland. The undrained shear strength on th... Chandler proposed the intrinsic strength line to correlate the undrained shear strength of samples one-dimensionally consolidated from slurry with the void index proposed by Burland. The undrained shear strength on the intrinsic strength line is different from the remolded undrained shear strength that is an important parameter for design and construction of land reclamation. The void index is used in this study for normalizing the remolded strength behavior of dredged deposits. A quantitative relationship between remolded undrained shear strength and void index is established based on extensive data of dredged deposits available from sources of literature. Furthermore, the normalized remolded undrained shear strength is compared with intrinsic strength line. The comparison result indicates that the ratio of undrained shear strength on the intrinsic strength line over remolded undrained shear strength increases with an increase in applied consolidated stress. 展开更多
关键词 consolidation stress dredged deposits intrinsic strength line remolded shear strength void index
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Experimental Realization of an Intrinsic Magnetic Topological Insulator 被引量:22
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作者 Yan Gong Jingwen Guo +21 位作者 Jiaheng Li Kejing Zhu Menghan Liao Xiaozhi Liu Qinghua Zhang Lin Gu Lin Tang Xiao Feng Ding Zhang Wei Li Canli Song Lili Wang Pu Yu Xi Chen Yayu Wang Hong Yao Wenhui Duan Yong Xu Shou-Cheng Zhang Xucun Ma Qi-Kun Xue Ke He 《Chinese Physics Letters》 SCIE CAS CSCD 2019年第7期66-71,共6页
An intrinsic magnetic topological insulator(TI) is a stoichiometric magnetic compound possessing both inherent magnetic order and topological electronic states. Such a material can provide a shortcut to various novel ... An intrinsic magnetic topological insulator(TI) is a stoichiometric magnetic compound possessing both inherent magnetic order and topological electronic states. Such a material can provide a shortcut to various novel topological quantum effects but remained elusive experimentally for a long time. Here we report the experimental realization of thin films of an intrinsic magnetic TI, MnBi2Te4, by alternate growth of a Bi2Te3 quintuple layer and a MnTe bilayer with molecular beam epitaxy. The material shows the archetypical Dirac surface states in angle-resolved photoemission spectroscopy and is demonstrated to be an antiferromagnetic topological insulator with ferromagnetic surfaces by magnetic and transport measurements as well as first-principles calculations. The unique magnetic and topological electronic structures and their interplays enable the material to embody rich quantum phases such as quantum anomalous Hall insulators and axion insulators at higher temperature and in a well-controlled way. 展开更多
关键词 intrinsic MAGNETIC STOICHIOMETRIC MAGNETIC well-controlled WAY
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Intrinsic apoptotic pathway and G2/M cell cycle arrest involved in tubeimoside I-induced EC109 cell death 被引量:14
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作者 Yang Xu Guanghui Wang +5 位作者 Quancheng Chen Ting Lin Zhiping Zeng Qiang Luo Jie Liu Cuiling Sun 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 2013年第3期312-321,共10页
Objective: Squamous esophageal carcinoma is highly prevalent in developing countries, especially in China. Tu Bei Mu (TBM), a traditional folk medicine, has been used to treat esophageal squamous cell carcinoma (E... Objective: Squamous esophageal carcinoma is highly prevalent in developing countries, especially in China. Tu Bei Mu (TBM), a traditional folk medicine, has been used to treat esophageal squamous cell carcinoma (ESCC) for a long term. tubeimoside I (TBMS1) is the main component of TBM, exhibiting great anticancer potential. In this study, we investigated the mechanism of TBMS1 cytotoxic effect on EC109 cells. Methods: Comparative nuclear proteomic approach was applied in the current study and we identified several altered protein spots. Further biochemical studies were carried out to detect the mitochondrial membrane potential, cell cycle and corresponding proteins' expression and location. Results: Subcellular proteomic study in the nucleus from EC109 cells revealed that altered proteins were associated with mitochondrial function and cell proliferation. Further biochemical studies showed that TBMSl-induced molecular events were related to mitochondria-induced intrinsic apoptosis and P21-cyclin B 1/cdc2 complex-related G2/M cell cycle arrest. Conclusions: Considering the conventional application of TBM in esophageal cancer, TBMS1 therefore may have a great potential as a chemotherapeutic drug candidate for ESCC. 展开更多
关键词 Anticancer drug G2/M cell cycle arrest intrinsic apoptosis subcellular proteomics and tubeimoside I(TBMS 1)
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Entanglement of a two-qubit anisotropic Heisenberg X Y Z chain in nonuniform magnetic fields with intrinsic decoherence 被引量:3
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作者 徐晓波 刘金明 于鹏飞 《Chinese Physics B》 SCIE EI CAS CSCD 2008年第2期456-461,共6页
Taking the intrinsic decoherence effect into account, this paper investigates the entanglement of a two-qubit anisotropic Heisenberg XYZ model in the presence of nonuniform external magnetic fields by employing the co... Taking the intrinsic decoherence effect into account, this paper investigates the entanglement of a two-qubit anisotropic Heisenberg XYZ model in the presence of nonuniform external magnetic fields by employing the concurrence as entanglement measure. It is found that both the intrinsic decoherence and the anisotropy of the system give a significant suppression to the entanglement. Moreover it finds that the initial state of the system plays an important role in the time evolution of the entanglement, which means that the entanglement of the system is independent of the nonuniformity and uniformity of the magnetic field when the system is in the initial state |ψ (0)) = |00) and [ψ′ (0)) = m |01) + n |10), respectively. 展开更多
关键词 Heisenberg XYZ chain CONCURRENCE magnetic field intrinsic decoherence
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Solitons and intrinsic localized modes in a one-dimensional antiferromagnetic chain 被引量:3
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作者 李德俊 米贤武 +1 位作者 邓科 唐翌 《Chinese Physics B》 SCIE EI CAS CSCD 2006年第1期39-44,共6页
By use of the Hartree approximation and the method of multiple scales, we investigate quantum solitons and intrinsic localized modes in a one-dimensional antiferromagnetic chain. It is shown that there exist solitons ... By use of the Hartree approximation and the method of multiple scales, we investigate quantum solitons and intrinsic localized modes in a one-dimensional antiferromagnetic chain. It is shown that there exist solitons of two different quantum frequency bands: i.e., magnetic optical solitons and acoustic solitons. At the boundary of the Brillouin zone, these solitons becornc quantum intrinsic localized modes: their quantum eigenfrequencics are below the bottom of the harmonic optical frequency band and above the top of the harmonic acoustic frequency band. 展开更多
关键词 antiferromagnetic chain Hartree approximation quantum soliton quantum intrinsic localized mode
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Predicting intrinsic disorder in proteins: an overview 被引量:11
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作者 Bo He Kejun Wang +3 位作者 Yunlong Liu Bin Xue Vladimir N Uversky A Keith Dunker 《Cell Research》 SCIE CAS CSCD 2009年第8期929-949,共21页
The discovery of intrinsically disordered proteins (IDP) (i.e., biologically active proteins that do not possess stable secondary and/or tertiary structures) came as an unexpected surprise, as the existence of suc... The discovery of intrinsically disordered proteins (IDP) (i.e., biologically active proteins that do not possess stable secondary and/or tertiary structures) came as an unexpected surprise, as the existence of such proteins is in contradiction to the traditional "sequence →structure →function" paradigm. Accurate prediction of a protein's predisposition to be intrinsically disordered is a necessary prerequisite for the further understanding of principles and mechanisms of protein folding and function, and is a key for the elaboration of a new structural and functional hierarchy of proteins. Therefore, prediction of IDPs has attracted the attention of many researchers, and a number of prediction tools have been developed. Predictions of disorder, in turn, are playing major roles in directing laboratory experiments that are leading to the discovery of ever more disordered proteins, and thereby leading to a positive feedback loop in the investigation of these proteins. In this review of algorithms for intrinsic disorder prediction, the basic concepts of various prediction methods for IDPs are summarized, the strengths and shortcomings of many of the methods are analyzed, and the difficulties and directions of future development of IDP prediction techniques are discussed. 展开更多
关键词 PROTEIN intrinsic disorder prediction method
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Engineering the Coordination Sphere of Isolated Active Sites to Explore the Intrinsic Activity in Single-Atom Catalysts 被引量:16
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作者 Xin Wu Huabin Zhang +4 位作者 Shouwei Zuo Juncai Dong Yang Li Jian Zhang Yu Han 《Nano-Micro Letters》 SCIE EI CAS CSCD 2021年第9期136-163,共28页
Reducing the dimensions of metallic nanoparticles to isolated,single atom has attracted considerable attention in heterogeneous catalysis,because it significantly improves atomic utilization and often leads to distinc... Reducing the dimensions of metallic nanoparticles to isolated,single atom has attracted considerable attention in heterogeneous catalysis,because it significantly improves atomic utilization and often leads to distinct catalytic performance.Through extensive research,it has been recognized that the local coordination environment of single atoms has an important influence on their electronic structures and catalytic behaviors.In this review,we summarize a series of representative systems of single-atom catalysts,discussing their preparation,characterization,and structure-property relationship,with an emphasis on the correlation between the coordination spheres of isolated reactive centers and their intrinsic catalytic activities.We also share our perspectives on the current challenges and future research promises in the development of single-atom catalysis.With this article,we aim to highlight the possibility of finely tuning the catalytic performances by engineering the coordination spheres of single-atom sites and provide new insights into the further development for this emerging research field. 展开更多
关键词 Isolated atoms Coordination sphere intrinsic activity Single-atom catalysts
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Water relations and an expression analysis of plasma membrane intrinsic proteins in sensitive and tolerant rice during chilling and recovery 被引量:11
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作者 Xin Yu Yan Hui Peng +3 位作者 Min Hua Zhang Yan Jun Shao Wei Ai Su Zhang Cheng Tang 《Cell Research》 SCIE CAS CSCD 2006年第6期599-608,共10页
A symptom of chilling injury is development of water deficit in shoots, resulting from an imbalance of water transport and transpiration. In this work, two rice varieties (Oryza sativa L. var. Wasetoitsu and Somewake... A symptom of chilling injury is development of water deficit in shoots, resulting from an imbalance of water transport and transpiration. In this work, two rice varieties (Oryza sativa L. var. Wasetoitsu and Somewake) seedlings were chilled at 7 ℃, followed by recovery at 28 ℃. Based on the growth phenotype and electrolyte leakage tests, Somewake was shown to be a chilling-tolerant variety, and Wasetoitsu a chilling-sensitive one. The chilling stress reduced markedly the relative water content (RWC) of leaves, accumulative transpiration and osmotic root hydraulic conductivity (Lp) in both varieties. But when retumed to 28 ℃, the water relation balance of Somewake recovered better. The mRNA expression profile of all the 11 plasma membrane intrinsic proteins (PIPs), a subgroup of aquaporins, was subsequently determined by real-time reverse transcription (RT)-PCR with TaqMan-minor grove binder (MGB) probes derived from rice var. Nipponbare during chilling treatment and recovery. Most of the PIP genes was down-regulated at the low temperature, and recovered at the warm temperature. The relative expression of some PIPs in both Somewake and Wasetoitsu decreased in parallel during the chilling. However during the recovery, the relative expression of OsPIP1;1, OsPIP2;1, OsPIP2;7 in shoots and OsPIP1:1, OsPIP2:1 in roots were significantly higher in Somewake than Wasetoitsu. This supports the role of PIPs in re-establishing water balance after chilling conditions. We discuss the diversified roles played by members of the aquaporin PIP subfamily in plant chilling tolerance depending on aquaporin isoforms, plant tissue and the stage of chilling duration. 展开更多
关键词 AQUAPORIN CHILLING gene expression plasma membrane intrinsic protein RICE
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