Alzheimer’s disease (AD) is considered a slow neuronal dysfunction process through hypoxia, ischemia and leads to apoptosis mediated senile plaques and neurofibrillary tangles (NFTs). Due to non-invasive approach of ...Alzheimer’s disease (AD) is considered a slow neuronal dysfunction process through hypoxia, ischemia and leads to apoptosis mediated senile plaques and neurofibrillary tangles (NFTs). Due to non-invasive approach of plaque characterization, computational techniques based on Brownian dynamics simulation are unique to speculate the electrostatic and kinetic properties of Acetylcho-linesterase (AChE). Typically the MRI spectros-copy high choline peak and enzyme specific to Alzheimer’s Disease (specificity constant (kcat/Km) of AChE) appeared associated with apoptosis and hypoxia. A simple display between synergy of cytokines, apoptosis, elevated AChE and choline is postulated as initial events. The events may be distributed heterogeneously within the senile plaques and neurofibrillary tangles (NFTs) of Alzheimer’s Disease (AD). The role of decreased brain AChE and synergy was associated with specific Magnetic Resonance Spectroscopic (MRS) pattern profiles in AD. These findings suggest that that the altered AChE and early apoptosis events in AD may be associated with specific MR spectral peak patterns. This study opens the possibility of reduced AChE levels causing high choline and reduced N-acetyl ace-tate (NAA) neurotransmitter by MRS after initial apoptosis and/or inflammation to make amyloid plaques in the cerebral tissue of Alzheimer’s disease (AD) patients. These results can be useful in clinical trials on AD lesions.展开更多
REFERENCES [1, 2] prove that ionic radii will increase or decrease with temperature rising orlowering. If the ionic radii at room temperature are known, many phenomena of the ioniccompounds occurring at room temperatu...REFERENCES [1, 2] prove that ionic radii will increase or decrease with temperature rising orlowering. If the ionic radii at room temperature are known, many phenomena of the ioniccompounds occurring at room temperature can be explained. Also if the ionic radii at high tem-perature are known, many phenomena of the ionic compounds occurring at high temperaturecan also be explained. Therefore, to calculate the effective radii of ions at high temperature isconsidered of great significance. For example, the 'investigation of KIO<sub>3</sub>-CsIO<sub>3</sub>展开更多
Modeling of biomolecular systems plays an essential role in understanding biological processes, such as ionic flow across channels, protein modification or interaction, and cell signaling. The continuum model describe...Modeling of biomolecular systems plays an essential role in understanding biological processes, such as ionic flow across channels, protein modification or interaction, and cell signaling. The continuum model described by the Poisson- Boltzmann （PB）/Poisson-Nernst-Planck （PNP） equations has made great contributions towards simulation of these pro- cesses. However, the model has shortcomings in its commonly used form and cannot capture （or cannot accurately capture） some important physical properties of the biological systems. Considerable efforts have been made to improve the con- tinuum model to account for discrete particle interactions and to make progress in numerical methods to provide accurate and efficient simulations. This review will summarize recent main improvements in continuum modeling for biomolecu- lar systems, with focus on the size-modified models, the coupling of the classical density functional theory and the PNP equations, the coupling of polar and nonpolar interactions, and numerical progress.展开更多
The Raman and infrared spectra, resistivity as well as thermoelectric power of Y 1- x Nd x Sr 2Cu 2.7 Mo 0.3 O 7- δ ( x =0, 0.1, 0.2, 0.5, 0.8 and 1.0) are studied carefully. It was found that the structure character...The Raman and infrared spectra, resistivity as well as thermoelectric power of Y 1- x Nd x Sr 2Cu 2.7 Mo 0.3 O 7- δ ( x =0, 0.1, 0.2, 0.5, 0.8 and 1.0) are studied carefully. It was found that the structure characteristics of RSr 2Cu 2.7 Mo 0.3 O 7- δ cuprates are different from those of RBa 2Cu 3O 7- δ . The variations of the microstructure in Y 1- x Nd x Sr 2Cu 2.7 Mo 0.3 O 7- δ with Nd doping affect the carrier distribution, so as a result the superconductivity changes. Furthermore, it is pointed out that the microstructure variations with the large rare earth ionic substitution cause the widely existing rare earth ionic size effect in HTSC.展开更多
文摘采用流动电位法,用固体表面电位测定仪考察电解质溶液种类、浓度、p H对纳滤膜表面Zeta电位的影响。结果表明,二价离子溶液比一价离子溶液对纳滤膜表面Zeta电位作用明显,同价态离子的离子半径越小,Zeta电位越大;随着离子强度的增加,Zeta电位越小,在低离子浓度下Zeta电位值稳定性,重复性好;随着溶液p H的变化(3~10),纳滤膜的表面呈现两性性质,等电位点在p H 4.5~5.0之间。在测试纳滤膜表面Zeta电位时,推荐选择0.001mol/L的KCl电解质溶液。
文摘Alzheimer’s disease (AD) is considered a slow neuronal dysfunction process through hypoxia, ischemia and leads to apoptosis mediated senile plaques and neurofibrillary tangles (NFTs). Due to non-invasive approach of plaque characterization, computational techniques based on Brownian dynamics simulation are unique to speculate the electrostatic and kinetic properties of Acetylcho-linesterase (AChE). Typically the MRI spectros-copy high choline peak and enzyme specific to Alzheimer’s Disease (specificity constant (kcat/Km) of AChE) appeared associated with apoptosis and hypoxia. A simple display between synergy of cytokines, apoptosis, elevated AChE and choline is postulated as initial events. The events may be distributed heterogeneously within the senile plaques and neurofibrillary tangles (NFTs) of Alzheimer’s Disease (AD). The role of decreased brain AChE and synergy was associated with specific Magnetic Resonance Spectroscopic (MRS) pattern profiles in AD. These findings suggest that that the altered AChE and early apoptosis events in AD may be associated with specific MR spectral peak patterns. This study opens the possibility of reduced AChE levels causing high choline and reduced N-acetyl ace-tate (NAA) neurotransmitter by MRS after initial apoptosis and/or inflammation to make amyloid plaques in the cerebral tissue of Alzheimer’s disease (AD) patients. These results can be useful in clinical trials on AD lesions.
文摘REFERENCES [1, 2] prove that ionic radii will increase or decrease with temperature rising orlowering. If the ionic radii at room temperature are known, many phenomena of the ioniccompounds occurring at room temperature can be explained. Also if the ionic radii at high tem-perature are known, many phenomena of the ionic compounds occurring at high temperaturecan also be explained. Therefore, to calculate the effective radii of ions at high temperature isconsidered of great significance. For example, the 'investigation of KIO<sub>3</sub>-CsIO<sub>3</sub>
基金supported by the National Natural Science Foundation of China(Grant No.91230106)the Chinese Academy of Sciences Program for Cross&Cooperative Team of the Science&Technology Innovation
文摘Modeling of biomolecular systems plays an essential role in understanding biological processes, such as ionic flow across channels, protein modification or interaction, and cell signaling. The continuum model described by the Poisson- Boltzmann （PB）/Poisson-Nernst-Planck （PNP） equations has made great contributions towards simulation of these pro- cesses. However, the model has shortcomings in its commonly used form and cannot capture （or cannot accurately capture） some important physical properties of the biological systems. Considerable efforts have been made to improve the con- tinuum model to account for discrete particle interactions and to make progress in numerical methods to provide accurate and efficient simulations. This review will summarize recent main improvements in continuum modeling for biomolecu- lar systems, with focus on the size-modified models, the coupling of the classical density functional theory and the PNP equations, the coupling of polar and nonpolar interactions, and numerical progress.
文摘The Raman and infrared spectra, resistivity as well as thermoelectric power of Y 1- x Nd x Sr 2Cu 2.7 Mo 0.3 O 7- δ ( x =0, 0.1, 0.2, 0.5, 0.8 and 1.0) are studied carefully. It was found that the structure characteristics of RSr 2Cu 2.7 Mo 0.3 O 7- δ cuprates are different from those of RBa 2Cu 3O 7- δ . The variations of the microstructure in Y 1- x Nd x Sr 2Cu 2.7 Mo 0.3 O 7- δ with Nd doping affect the carrier distribution, so as a result the superconductivity changes. Furthermore, it is pointed out that the microstructure variations with the large rare earth ionic substitution cause the widely existing rare earth ionic size effect in HTSC.
