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Sleep as a window to understand and regulate Alzheimer's disease:emerging roles of thalamic reticular nucleus

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Neural Regeneration Research 2025年第6期20卷 1711-1712页

作者： Haoqi Sun Shiqian shen Robert j.Thomas M.Brandon Westover Can Zhang Department of Neurology Beth Israel Deaconess Medical CenterHarvard Medical SchoolBostonMAUSA Center for Translational Pain Research Department of AnesthesiaCritical Care and Pain MedicineMassachusetis General HospitalHarvard Medical SchoolBostonMAUSA Division of Pulmonary Critical Care and Sleep MedicineDepartment of MedicineBeth Israel Deaconess Medical CenterHarvard Medical SchoolBostonMAUSA Genetics and Aging Research Unit McCance Center for Brain HealthMass General Institute for Neurodegenerative DiseaseDepartment of NeurologyMassachusetts General HospitalHarvard Medical SchoolBostonMAUSA

Introduction:Alzheimer 's disease(AD) is a common neurodegenerative disorder and the primary cause of dementia. Considerable evidence supports the “amyloid hypothesis,” stating that the pathogenesis of AD is primarily caused by the deposition of amyloid-β(Aβ), which drives tau phosphorylation, neuroinflammation, and neurodegeneration in the brain. The amyloid hypothesis is strengthened by the significant and moderate benefit of lecanemab, a humanized antibody through an anti-amyloid mechanism,showing slowed clinical decline(van Dyck et al.,2023). The recent positive results of anti-amyloid trials have brought back focus on the amyloid hypothesis through biochemical, genetic, and pharmacological approaches(Zhang, 2023).

关键词： Alzheimer inflammation hypothesis

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低空经济的内涵、特征和运行模式

新疆师范大学学报（哲学社会科学版） 2025年第1期46卷 108-117,F0002页

作者：沈映春北京航空航天大学公共管理学院北京100083

低空经济作为低空飞行活动与产业融合的新型综合性经济形态,具有空间立体性、区域依赖性、数字生态性、产业融合性以及辐射带动性等特征。党和政府高度重视发展低空经济,将其确定为国家战略性新兴产业,各地加紧布局,发展势头良好。但具... 详细信息

低空经济作为低空飞行活动与产业融合的新型综合性经济形态,具有空间立体性、区域依赖性、数字生态性、产业融合性以及辐射带动性等特征。党和政府高度重视发展低空经济,将其确定为国家战略性新兴产业,各地加紧布局,发展势头良好。但具体实践中仍存在发展低空经济的体制机制不畅、技术创新支持不足、新型基础设施不全、产业领域需不断拓展等问题。针对上述问题,文本依据螺旋理论,提出“政产学研金服用”的低空经济开放式创新生态模式。

关键词：低空经济新质生产力战略性新兴产业开放式创新生态运行模式

Theory and classification of mass extinction causation

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National Science Review 2024年第1期11卷 16-36页

作者： Thomas j.Algeo jun shen State Key Laboratory of Biogeology and Environmental Geology China University of Geosciences—Wuhan State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences—Wuhan Department of Geosciences University of Cincinnati

Theory regarding the causation of mass extinctions is in need of systematization, which is the focus of this contribution. Every mass extinction has both an ultimate cause, i.e. the trigger that leads to various climato-environmental changes, and one or more proximate cause(s), i.e. the specific climato-environmental changes that result in elevated biotic mortality. With regard to ultimate causes, strong cases can be made that bolide(i.e. meteor) impacts, large igneous province(LIP) eruptions and bioevolutionary events have each triggered one or more of the Phanerozoic Big Five mass extinctions, and that tectono-oceanic changes have triggered some second-order extinction events. Apart from bolide impacts, other astronomical triggers(*** flares, gamma bursts and supernova explosions) remain entirely in the realm of speculation. With regard to proximate mechanisms, most extinctions are related to either carbon-release or carbon-burial processes, the former being associated with climatic warming, ocean acidification, reduced marine productivity and lower carbonate δ13C values, and the latter with climatic cooling, increased marine productivity and higher carbonate δ13C values. Environmental parameters such as marine redox conditions and terrestrial weathering intensity do not show consistent relationships with carbon-cycle *** this context, mass extinction causation can be usefully classified using a matrix of ultimate and proximate factors. Among the Big Five mass extinctions, the end-Cretaceous biocrisis is an example of a bolide-triggered carbon-release event, the end-Permian and end-Triassic biocrises are examples of LIP-triggered carbon-release events, and the Late Ordovician and Late Devonian biocrises are examples of bioevolution-triggered carbon-burial events. Whereas the bolide-impact and LIP-eruption mechanisms appear to invariably cause carbon release, bioevolutionary triggers can result in variable carbon-cycle changes, e.g. carbon burial durin

关键词： biocrisis ultimate cause proximate cause bolide large igneous province bioevolutionary event

On s-Reflexive Spaces and Continuous Selections

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Chinese Annals of Mathematics,Series B 2015年第2期36卷 181-194页

作者： Rongxin shen Heikki j K jUNNILA Department of Mathematics Taizhou University Department of Mathematics and Statistics University of Helsinki

This paper deals with the s-reflexive spaces introduced by Yang and Zhao. The authors prove that every s-reflexive Hausdorff space is zero-dimensional, and indicate a close relationship between the theory of s-reflexi... 详细信息

关键词： s-Reflexive Continuous selection Zero-Dimensional Retractifiable

Studies on Heterobinuclear Complexes of Ln^(3+) and Zn^(2+) with Acyclic Polyether Schiff Base

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journal of Rare Earths 1999年第2期17卷 79-81页

作者： Wu, j Yao, KM shen, LF Zhejiang Univ Dept Chem Hangzhou 310027 Peoples R China Hangzhou Teacher Coll Dept Chem Hangzhou 310012 Peoples R China Chinese Acad Sci Wuhan Inst Phys & Math Lab Magnet Resonance & Mol Phys Wuhan 430071 Peoples R China

Eight novel heterobinuclear complexes of Ln3+ and Zn2+ with salicylidene diethylene glycol diamine(SALDA) Schiff base (NO3)22H2O(Ln=Pr, Nd, Sm, Gd, Tb, Er, Yb, Y) were synthesized and characterized on the basis of IR and UV, particularly by1H and13C NMR spectra. It is confirmed that the azomethine nitrogen, ethereal oxygen and a part of phenolic oxygen atoms coordinate to the central ions.

关键词： Rare earths Zinc Acyclic schiff base Heterobinuclear complex Synthesis

INVESTIGATION OF PHOTOELECTROCHROMIC THIN FILM AND DEVICE

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Acta Metallurgica Sinica(English Letters) 2005年第3期18卷 275-279页

作者： M.j.Chen H.shen CollegeofSciences SouthChinaAgricultureUniversityGuangzhou510642China CollegeofPhysicsandEngineering ZhongshanUniversityGuangzhou510275China

Photoelectrochromic device is a combination of dye-sensitized solar cells and el ectrochromic WO3 layers. Ectrochroelmic WO3 layer and TiO2 layer had been prepar ed by the sol-gel process, then be assembled to pohotoelectrochromic device. The effects of heating temperature on photoelectrochromic were investigated. The re sults showed that thin films prepared by dip-coating and spin-coating had good f ilm quality and the device made by the method mentioned in the paper had good ph otoelectrochromic properties.

关键词： WO3 ,TiO2 photoelectrochromic sol-gel

Some micromechanical models of elastoplastic behaviors of porous geomaterials

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journal of Rock Mechanics and Geotechnical Engineering 2017年第1期9卷 1-17页

作者： W.Q. shen j.F. Shao Laboratory of Mechanics of Lille University of Lille I Villeneuve d’Ascq 59655 France

Some micromechanics-based constitutive models are presented in this study for porous *** micro-macro mechanical models focus on the effect of porosity and the inclusions on the macroscopic elastoplastic behaviors of porous materials. In order to consider the effect of pores and the compressibility of the matrix, some macroscopic criteria are presented firstly for ductile porous medium having one population of pores with different types of matrix(von Mises, Green type, Misese Schleicher and Druckere Prager). Based on different homogenization techniques, these models are extended to the double porous materials with two populations of pores at different scales and a Druckere Prager solid phase at the microscale. Based on these macroscopic criteria, complete constitutive models are formulated and implemented to describe the overall responses of typical porous geomaterials(sandstone,porous chalk and argillite). Comparisons between the numerical predictions and experimental data with different confining pressures or different mineralogical composites show the capabilities of these micromechanics-based models, which take into account the effects of microstructure on the macroscopic behavior and significantly improve the phenomenological ones.

关键词： Homogenization Porous geomaterials Ductile behavior Double porosity Macroscopic strength Plastic compressibility Druckere Prager solids

Formation mechanism and mechanical properties of surface nanocrystallized Ti-6Al-4V alloy processed by surface mechanical attrition treatment

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Rare Metals 2023年第4期42卷 1343-1352页

作者： Yi-Feng Li Cheng Chen j.Ranabhat Yi-Fu shen College of Materials Science and Technology Nanjing University of Aeronautics and AstronauticsNanjing210016China

In the present work,surface mechanical attrition treatment(SMAT)was proposed to achieve surface nanocrystallization on Ti-6Al-4V surface via high-energy planetary ball milling method using a planetary ball *** characteristics of microstructure were studied using different *** nanocrystallization is achieved on Ti-6Al-4V *** process of refinement could be summarized into four *** the refinement process,the reticular continuous beta phase performs a significant role,it cracked,broke up and moved to each side along the grain *** movement of beta grains has the capabilities of effectively optimizing the grain orientation and accelerating the further refinement of alpha *** also plays an important role during the *** grain orientation between different types of grains seems to be larger than that of same type *** interface will be divided into smaller nanocrystalline grains once the dislocation density breaks the ***,the balance will be achieved again and owns a higher critical value which cannot be broken,then a stable grain size can be achieved *** results of microhardness,friction coefficient and wear mass loss tests of SMAT samples indicate that the mechanical behaviors of substrate are greatly enhanced after this novel SMAT treatment.

关键词： Surface nanocrystallization Dual-phase titanium alloy SMAT Mechanical properties

Asymmetric Reformatsky Reaction Induced by Dipeptides

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Chinese Chemical Letters 2000年第8期11卷 659-662页

作者： Wang, ZY shen, j.j.ang, CS You, TP Univ Sci & Technol China Dept Chem Hefei 230026 Peoples R China

For the first time, synthetic dipeptides were applied to the catalysis of asymmetric Reformatsky reaction. Review in this domain & factors influencing enantioselectivity were discussed.

关键词： dipeptide derivative chiral ligands catalysis asymmetric Reformatsky reaction