检索结果-南通市图书馆

Targeting epigenetic mechanisms in amyloid-β-mediated Alz.eimer’s pathophysiology:unveiling therapeutic potential

Neural Regeneration Research 2025年第1期20卷 54-66页

作者： Jennie z.Li Nagendran Ramalingam Shaomin Li Ann Romney Center for Neurologic Diseases Brigham and Women’s Hospital and Harvard Medical SchoolBostonMAUSA

Alz.eimer’s disease is a prominent chronic neurodegenerative condition characteriz.d by a gradual decline in memory leading to *** evidence suggests that Alz.eimer’s disease is associated with accumulating various amyloid-βoligomers in the brain,influenced by complex genetic and environmental *** memory and cognitive deficits observed during the prodromal and mild cognitive impairment phases of Alz.eimer’s disease are believed to primarily result from synaptic *** life,environmental factors can lead to enduring changes in gene expression and the emergence of brain *** changes,known as epigenetic modifications,also play a crucial role in regulating the formation of synapses and their adaptability in response to neuronal *** this context,we highlight recent advances in understanding the roles played by key components of the epigenetic machinery,specifically DNA methylation,histone modification,and microRNAs,in the development of Alz.eimer’s disease,synaptic function,and activity-dependent synaptic ***,we explore various strategies,including enriched environments,exposure to non-invasive brain stimulation,and the use of pharmacological agents,aimed at improving synaptic function and enhancing long-term potentiation,a process integral to epigenetic ***,we deliberate on the development of effective epigenetic agents and safe therapeutic approaches for managing Alz.eimer’s *** suggest that addressing Alz.eimer’s disease may require distinct tailored epigenetic drugs targeting different disease stages or pathways rather than relying on a single drug.

关键词： Alz.eimer’s disease DNA methylation enriched environments histone modification microRNAs non-invasive brain stimulation synaptic plasticity

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

ON THE L_∞ CONVERGENCE AND THE EXTRAPOLATION METHOD OF A DIFFERENCE SCHEME FOR NONLOCAL PARABOLIC EQUATION WITH NATURAL BOUNDARY CONDITIONS

引用

Journal of Computational Mathematics 2001年第5期19卷 449-458页

作者： Wan, z.-S. Sun, z.-z. Institute of Applied Physics and CM P.O. Box 8009 Beijing 100088 China

In paper (J. Comput. Appl. Math., 76 (1996), 137-146), a difference scheme for a class of nonlocal parabolic equations with natural boundary conditions was derived by the method of reduction of order and the unique solvability and second order convergence in L2-norm are proved. In this paper, we prove that the scheme is second order convergent in L∞ norm and then obtain fourth order accuracy approximation in L∞ norm by extrapolation method. At last, one numerical example is presented.

关键词： Approximation theory Boundary conditions Convergence of numerical methods Extrapolation

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Surface Wettability and Chemistry of Oz.ne Perfusion Processed Porous Collagen Scaffold

引用

Journal of Bionic Engineering 2011年第3期8卷 223-233页

作者： Chaoz.ng liu Shirley z. Shen 乙hiwu Han School of Mechanical and Systems Engineering University of Newcastle Newcastle upon Tyne NEI 7R U UK Polymer Composite & Nanomaterials CSIRO Manufacturing & Infrastructure Technology Highett Vic 3190 Australia Key Laboratory of Bionic Engineering (Ministry of Education China) Jilin University Changchun 130022 P. R. China

Crosslinking treatment of collagen has often been used to improve the biological stability and mechanical properties of 3D porous collagen scaffolds. However, accompanying these improvements, the collagen fibril surface becomes hydrophobic nature resulting in a reduced surface wettability. The wetting of the collagen fibril by culture medium is reduced and it is difficult for the medium to diffuse into the 3D structure of a porous collagen scaffold. This paper reports a ＂perfusion processing＂ strategy using oz.ne to improve the surface wettability of chemical crosslinked collagen scaffolds. Surface wettability, surface composition and biological stability were analyz.d to evaluate the effectiveness of this surface processing strategy. It was observed that oz.ne perfusion processing improved surface wettability for both exterior and interior surfaces of the porous 3D collagen scaffold. The improvement in wettability is attributed to the incorporation of oxygen-containing functional groups onto the surface of the collagen fibrils, as confirmed by X-ray Photoelectron Spectroscopy （XPS） analysis. This leads to a significant improvement in water taking capability without compromising the bulk biological stability and mechanical properties, and confirms that oz.ne perfusion processing is an effective tool to modify the wettability both for interior and exterior surfaces throughout the scaffold.

关键词： scaffold collagen surface modification hydrophilicity oz.ne perfusion

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Numerical Modeling and Analysis of Grooved Surface Applied to Film Cooling

引用

Journal of Bionic Engineering 2011年第4期8卷 464-473页

作者： L. Guo z. C. liu Y. Y. Yan z. W. Han Faculty of Engineering University of Nottingham Nottingham NG7 2RD UK Department of Internal Combustion Engine Jilin University Changchun 130022 P. R. China Key Laboratory of Bionic Engineering （Ministry of Education China） Jilin University Changchun 130022 P. R. China

In order to improve the efficiency of film cooling, numerical investigation was carried out to study the effects of different film-cooled plates on surface heat transfer. Both grooved and non-grooved surfaces were concerned. The modeling was per- formed using Fluent software with the adoption of Shear-Stress Transport （SST） k-ωmodel as the turbulence closure. The coolant was supplied by a single film cooling hole with an inclination angle of 30°. The Mach numbers for the coolant flow and the mainstream flow were fixed at 0 and 0.6, respectively. At three blowing ratios of 0.5, 1.0 and 1.5, the aerodynamic behaviour of the mixing process as well as the heat transfer performance of the film cooling were presented. The numerical results were validated using experimental data extracted from a benchmark test. Good agreements between numerical results and the ex- perimental data were observed. For the film cooling efficiency, it shows that both local and laterally averaged cooling effectiveness can be improved by the non-smooth surface at different blowing ratios. Using the grooved surface, the turbulence intensity upon the plate can be reduced notably, and the mixing between the two flows is weakened due to the reduced turbu lence level. The results indicate that the cooling effectiveness of film cooling can be enhanced by applying the grooved surface.

关键词： film cooling non-smooth surface cooling effectiveness grooved structure blowing ratio

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

EFFECT OF GRAIN REFINING ON PRIMARYαPHASE IN SEMI-SOLID A356 ALLOY PREPARED BY LOW SUPERHEAT POURING AND SLIGHT ELECTROMAGNETIC STIRRING

引用

Acta Metallurgica Sinica(English Letters) 2008年第1期21卷 57-64页

作者： z. liu W.M. Mao z.D. z.ao Faculty of Material and Chemical Engineering Jiangxi University of Science and Technology Ganzhou 341000 China School of Material Science and Engineering University of Science ＆ Technology Beijing Beijing 100083 China

The semi-solid slurry of A356 alloy, which is grain-refined by Al-Ti-B master alloy, is prepared by low superheat pouring and slight electromagnetic stirring. The effects of grain refining on the morphology and the grain siz. of the primary α phase in the slurry manufactured are researched. The results indicate that the slurry with particle-like and rosette-like primary α phases can be prepared by low superheat pouring and slight electromagnetic stirring from liquid A356 alloy grain-refined, in which the pouring temperature can be suitably raised. Compared with the A356 samples without grain refining, the grain siz. and particle morphology of primary α phase as well as the distribution of the grain with particle-like or rosette-like along radial in the ingot in A356 are markedly improved by grain refining.

关键词： Semi-solid Grain-refined Low superheat pouring Slight electromagnetic stirring A356 alloy Al-Ti-B

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Stress analysis near the tips of a transverse crack in an elastic semi-strip

引用

Applied Mathematics and Mechanics(English Edition) 2017年第7期38卷 935-956页

作者： z. z.URAVLOVA Institute of Mathematics Economics and Mechanics Odessa I. I. Mechnikov National University Odessa 65082 Ukraine

The plane elastic problem for a semi-strip with a transverse crack is inves- tigated. The initial problem is reduced to a one-dimensional continuous problem by use of an integral transformation method with a generaliz.d scheme. The one-dimensional problem is first formulated as a vector boundary problem, and then reduced to a system of three singular integral equations （SIEs）. The system is solved by use of an orthogonal polynomial method and a special generaliz.d method. The contribution of this work is the consideration of kernel fixed singularities in solving the system. The crack length and its location relative to the semi-strip＇s lateral sides are investigated to simplify the problem＇s statement. This simplification reduces the initial problem to a system of two SIEs.

关键词： semi-strip transverse crack Green's function integral transformation,fixed singularity singular integral equation (SIE)

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

NEW VIEW ABOUT BAINITIC TRANSFORMATION IN STEEL

引用

Acta Metallurgica Sinica(English Letters) 1999年第3期12卷 229-234页

作者： liu, C.C. liu, z. Chen, G.X. Tsinghua Univ Beijing China

The bainitic transformation was analyz.d according to the factors such as morphology, crystallography, mechanical property of bainite and transformation kinetics. It was found that the bainitic transformation is controlled by displacive mechanism and self-tempering of displacive microstructure, i.e. bainite is the product of such procedure during which undercooled austenite first transforms into one certain displacive microstructure by displacive mechanism and then this microstructure experiences self-tempering. With this idea, several questions that can not be illustrated only by displacive transformation mechanism can be explained successfully.

关键词： Bainite Morphology Steel

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

LOW CYCLE FATIGUE BEHAVIOR OF Az.1HP ALLOY IN AS HIGHP RESSURE DIE CASTING

引用

Acta Metallurgica Sinica(English Letters) 2000年第4期13卷 961-966页

作者： liu, z. Xu, Y.Y. Wang, z.G. Wang, Y. liu, z.Y. Inst of Metal Research Chinese Acad of Sciences Shenyang China

Fully reversed total strain-controlled low-cycle fatigue tests were conducted at room temperature in air to study the fatigue behavior of Az.1HP magnesium alloy in as high pressure die casting and subsequently heat treatment. All the specimens in different heat histories exhibit cyclic strain hardening in different degrees. It is difficult to distinguish the fatigue behavior of the die casting specimens from that of the solution aging specimens. The solution treated specimens show longer fatigue life at high strain amplitude and shorter fatigue life at low strain amplitude than the die casting and solution aging specimens though they have the lowest yield strength with higher strain hardening. Fatigue fracture surfaces for strain amplitude larger than 0.005 show very similar to those found by monotonic tensile tests. The SEM examination reveals that the regions of fatigue crack growth and final fracture can be characteriz.d by quasi-cleavage mechanisms, but some shallow dimples, slip bands and secondary cracks are found on the fracture surface in the fracture crack growth areas.

关键词： Cracks Die casting Fatigue of materials Heat treatment

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Analysis of vibration reduction level in an 8/6 switched reluctance machine by active vibration cancellation

引用

Journal of z.ejiang University-Science C(Computers and Electronics) 2010年第10期11卷 808-816页

作者： Xu liu z.i-ping PAN z. Q. z.U School of Electrical Engineering Zhejiang University Hangzhou 310027 China Department of Electronic and Electrwal Engmeermg University of Sheffield Sheffield S1 3JD UK

This paper proposes an analytical model for predicting the maximum vibration reduction level in a four-phase 8/6 switched reluctance machine(SRM) by employing active vibration cancellation(AVC),one of the most effective and convenient methods for reducing the vibration and acoustic noise produced by *** on the proposed method,the factors that influence the vibration reduction level are analyz.d in *** relationships between vibration and noise reduction levels at resonance frequency and rotor speed are ***,it is shown that a large damping factor will lead to smaller vibration reduction level with AVC while,in contrast,a large resonance frequency will increase the vibration reduction *** finite element analyses and experiments were carried out on a prototype 8/6 SRM to validate the proposed method.

关键词： Active vibration cancellation Analytical model Switched reluctance machine Vibration

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Measurement, modelling, and closed-loop control of crystal shape distribution： Literature review and future perspectives

引用

Particuology 2016年第3期14卷 1-18页

作者： Cai Y. Ma Jing J. liu Xue z. Wang Institute of Particle Science and Engineering School of Chemical and Process Engineering University of Leeds Leeds 1.52 9JT United Kingdom School of Chemistry and Chemical Engineering South China University of Technology Guangzhou 510640 China

Crystal morphology is known to be of great importance to the end-use properties of crystal products, and to affect down-stream processing such as filtration and drying. However, it has been previously regarded as too challenging to achieve automatic closed-loop control. Previous work has focused on controlling the crystal siz. distribution, where the siz. of a crystal is often defined as the diameter of a sphere that has the same volume as the crystal. This paper reviews the new advances in morphological population balance models for modelling and simulating the crystal shape distribution （CShD）, measuring and estimating crystal facet growth kinetics, and two- and three-dimensional imaging for on-line characterisation of the crystal morphology and CShD. A framework is presented that integrates the various components to achieve the ultimate objective of model-based closed-loop control of the CShD. The knowledge gaps and challenges that require further research are also identified.

关键词： Crystal morphology Crystal shape distribution Morphological population balance mode3D process imaging Closed-loop control of crystal shapeCrystal facet growth kinetics

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：