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Hydroxytyrosol and Parkinson's disease:protective actions against alpha-synuclein toxicity

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neural Regeneration Research 2024年第7期19卷 1427-1428页

作者： Ruth Hornedo-Ortega Ana m.Espinosa-Oliva Departamento de nutrición y Bromatología Toxicología y Medicina LegalFacultad de FarmaciaUniversidad de SevillaSevilleSpain instituto de Biomedicina de Sevilla IBiS/Hospital Universitario Virgen del Rocío/CSIC/Universidad de SevillaSevillaSpain Departamento de Bioquímica y Biología molecular Facultad de FarmaciaUniversidad de SevillaSevillaSpain

Parkinson’s disease:Parkinson’s disease(PD) is the second most prevalent neurodegenerative disease,after Alzheimer’s disease,affecting 1%of the general population over the age of *** to data from the World Health Organization(WHO),its prevalence has doubled in the past 25 *** 2019,global estimates indicated over 8.5 million individuals with PD and it is suggested that PD caused 329000 deaths,an increase of over 100% since 2000(WHO,2022).

关键词： protective Alzheimer prevalence

HYDRATiOn AnD PHASE SEPARATiOn OF TemPERATURE-SEnSiTiVE WATER-SOLUBLE POLYmERS

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Chinese Journal of Polymer Science 2011年第1期29卷 13-21页

作者： Fumihiko Tanaka Tsuyoshi Koga Hiroyuki Kojima Francoise m.Winnik Department of Polymer Chemistry Graduate School of EngineeringKyoto University Department of Chemistry and Faculty of Pharmacy University of Montréal

Collapse of a poly（n-isopropylacrylamide）（PniPam） chain upon heating and phase diagrams of aqueous PniPam solutions with very fiat LCST phase separation line are theoretically studied on the basis of cooperative dehydration （simultaneous dissociation of bound water molecules in a group of correlated sequence）, and compared with the experimental observation of temperature-induced coil-globule transition by light scattering methods. The transition becomes sharper with the cooperativity parameter σ of hydration. Reentrant coil-globule-coil transition in mixed solvent of water and methanol is also studied from the viewpoint of competitive hydrogen bonds between polymer-water and polymer-methanol. The downward shift of the cloud-point curves （LCST cononsolvency） with the mole fraction of methanol due to the competition is calculated and compared with the experimental data. Aqueous solutions of hydophobically-modified PniPam carrying short alkyl chains at both chain ends （telechelic PniPam） are theoretically and experimentally studied. The LCST of these solutions is found to shift downward along the sol-gel transition curve as a result of end-chain association （association-induced phase separation）, and separate from the coil-globule transition line. Associated structures in the solution, such as flower micelles, mesoglobules and higher fractal assembly, are studied by USAnS with theoretical modeling of the scattering function.

关键词： Cooperative dehydration LCST phase separation Poly(n-isopropylacrylamide) Cononsolvency Coil-globule transition Flower micelle.

Effects of Plasticizers,Antioxidants and Burning Rate modifiers on Aging Performance of the HTPB/HmDi Composite Solid Propellant

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含能材料 2019年第1期27卷 21-27,90页

作者： Ahmed m Enew Ehab Abadir Sahar Elmarsafy Karim K Elsharkawy Chemical Department Faculty of EngineeringCairo University School of Chemistry and Environment Beijing University of Aeronautics and Astronautics

The effects of plasticizers,antioxidants and burning rate modifiers on the aging performance of the composite solid propellant based on hydroxyl-terminated polybutadiene(HTPB)/hexamethylene diisocyanate(HmDi)were explored by apply-ing an accelerated aging program for 90 day at 70 ℃. The HTPB propellant matrix with the diisooctyl sebacate(DOS)as plasti-cizers and diisooctyl azelate(DOZ), antioxidants as n,n ′-Diphenyl-p-phenylenediamine(AO) and 2,2′-methylenebis(4-methyl-6-tert-butylphenol)(cyanox 2246)and burning rate modifiers as barium ferrite(BF),copper chromites(CC)and fer-ric oxide(FO)were varied. Results show that sample(S1)which based on DOS decreases the stress value and increases the strain value which considered to be an excellent start for aging program. Sample(S3)containing AO presents the higher resis-tance to oxidation showing the better performance that reflects on increasing the shelf life of the composite solid propellant mo-tor. Sample(S5)which based on BF enhances the ballistic performance among over the other tested two samples. The accelerat-ed aging program allowed us to estimate the motor in-service lifetime.

关键词： polybutadiene(HTPB)/hexamethylene diisocyanate(HmDi)composite solid propellant plasticizers antioxidants burning rate modifiers aging program

Combined effects of two sulfonylurea herbicides on soil microbial biomass and n-mineralization

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Journal of Environmental Sciences 2001年第3期13卷 311-317页

作者： A.m.EL-Ghamry HUAnG Chang-yong XU Jian-ming College of natural Resources and Environmental Sciences Zhejiang UniversityHangzhou 310029China

The interaction effect of two sulfonylurea herbicides, bensulfuron methyl (B) and metsulfuron methyl(m), were tested on microbial biomass C, n, n mineralization and C/n ratio in a loamy sand soil. The herbicides were applied at various levels of: control (B0m0), 0.01 and 0.01 (B1m1), 0.01 and 0.1 (B1m2), and 0.01 and 1.0 (B1m3) μg/g soil. Determinations of soil microbial biomass C, n and n mineralization contents were carried out at 1, 3, 5, 7, 10, 15, 25 and 45 days after herbicides application. The results showed that the soil microbial biomass C (C mic ) and microbial biomass n (n mic ) decreased consistently with the increasing rates of herbicides. The results further indicated that B1m1 and B1m2 caused a significant reduction in C mic and n mic within first 10 and 7 days of incubation, respectively, as compared with the control. These reductions in C mic and n mic were also significant ( P =0.05) with B1m3 application especially within first 15 days of incubation. A significant reduction in n mineralization (n min) was observed with high doses (B1m2, B1m3) of herbicides within first 5 days of incubation, while low rate (B1m1) failed to produce any significant effect. An increase in the soil microbial biomass C:n ratio was also noted.

关键词： bensulfuron methyl metsulfuron methyl C mic n mic n mineralization loamy sand soil

美国犹他州瓦萨奇断裂带的分段模式及其全新世活动史

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地震地质译丛 1992年第4期14卷 4-11页

作者： m.n.machette 勇孟琦

瓦萨奇断裂(WFZ)是美国西部最长且最活动的张性断裂带之一。它是将盆地山脉-省东部和科罗拉多高原西部及落基山脉中部地带分隔开来的主转换带的主要构造组成部分。该断裂带第四纪晚期在从爱达荷州的马拉德城到犹他州的费耶特长达343公... 详细信息

瓦萨奇断裂(WFZ)是美国西部最长且最活动的张性断裂带之一。它是将盆地山脉-省东部和科罗拉多高原西部及落基山脉中部地带分隔开来的主转换带的主要构造组成部分。该断裂带第四纪晚期在从爱达荷州的马拉德城到犹他州的费耶特长达343公里地段均有活动迹象。其主要表现为发育于中—晚更新世的冰川相、湖相、崩积和冲积层中的大规模断层崖及全新世地层中的较小规模的断层崖。

关键词：地震断裂带分段模式全新世

High Blood Pressure Effects on the Brain Barriers and Choroid Plexus Secretion

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neuroscience & medicine 2012年第1期3卷 60-64页

作者： ibrahim González-marrero Leandro Castaneyra-Ruiz Juan m.González-Toledo Agustín Castaneyra-Ruiz Héctor de Paz-Carmona Lidia Ruiz-mayor Agustín Castaneyra-Perdomo emilia m.Carmona-Calero Departamento de Anatomía Facultad de MedicinaUniversidad de La LagunaTenerifeSpain Departamento de Biotecnología Instituto de Investigación y Ciencias de Puerto del RosarioFuerteventuraSpain

High blood pressure produces ventricular dilation, variations in circumventricular organs and changes in the cerebrospinal fluid compositions. On the other hand, chronic hypertension in spontaneously hypertensive rats can cause changes in the integrity of the brain barriers: blood-cerebrospinal fluid barrier and blood brain barrier. The permeability of the brain barriers can be studied by using transthyretin and S-100β. in the present work we study the integrity of the brain barrier and the choroid plexus function variations in arterial hypertension. Control rats and spontaneously hypertensive rats were used and the choroid plexus were processed by immunohistochemistry with anti-transthyretin and anti-vasopressin. Western blot was also performed in cerebrospinal fluid, serum and choroid plexus using anti-S-100β, anti-transthyretin. The accumulation of transthyretin immunoreactive was bigger in spontaneously hypertensive rats with respect to the control. Vasopressin was also higher in spontaneously hypertensive rats with respect to the control. Western blot showed that transthyretin tetramer was higher in the spontaneously hypertensive rats than in the control rats. The expression of transthyretin monomer was lower in hypertensive rats than the control in the cerebrospinal fluid, the transthyretin monomer reaction in the blood was stronger in hypertensive than in control rats. Western blot for the S-100 β showed an increase in blood and cerebrospinal fluid of hypertensive rats. The high blood pressure produces a disruption of the blood brain barrier and blood to cerebrospinal fluid barrier that allows extravasations from the cerebrospinal fluid to the blood and from the blood to the cerebrospinal fluid.

关键词： Brain Barriers Choroid Plexus Arterial Hypertension

Electrochemical behavior of cerium(Ⅳ) in a RTiL and its mixture with ethanol

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Journal of Rare Earths 2014年第7期32卷 641-647页

作者： Arijit Sengupta m.S.murali P.K.mohapatra Radiochemistry Division Bhabha Atomic Research Centre

A systematic study was carried out to explore the electrochemical behavior of Ce in room temperature ionic liquid（CnmimBr, where n=6, 8, 10） and mixture of C6 mimBr and ethanol by cyclic voltammetry. With increase in the number of carbon atoms on the alkyl substituent on methyl imidazolium cation, the electrochemical window of the ionic liquids was found to extend towards more negative potential value, as a result there was a possibility of reduction of Ce to lower oxidation states. The diffusion coefficient and activation energy for the diffusion were calculated in all the ionic liquids and one of their mixtures with ethanol. With increase in n value, the diffusion coefficient of Ce decreased due to increase in viscosity of the medium while the activation energy for the diffusion followed a reverse trend for C6 mimBr, C8 mimBr and C10 mimBr, respectively. The observations indicated that the nature of species of Ce might be different in room temperature ionic liquids（RTiLs） from that present in their mixtures with ethanol.

关键词： cerium cyclic voltammetry diffusion coefficient activation energy ethanol Cn mimBr (n=6, 8, 10) rare earths

Crystallization and impact history of a meteoritic sample of early lunar crust(nWA 3163)refined by atom probe geochronology

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Geoscience Frontiers 2019年第5期10卷 1841-1848页

作者： L.F. White D.E. moser K.T. Tait B. Langelier i. Barker J.R. Darling Centre for Applied Planetary mineralogy Department of Natural HistoryRoyal Ontario MuseumTorontoOntarioM5S 2C6Canada Department of Earth Sciences University of TorontoTorontoOntarioM5S 3B1Canada Department of Earth Sciences University of Western OntarioLondonN6A 5B7Canada Canadian Centre for Electron microscopy McMaster UniversityHamiltonOntarioCanada School of Earth and Environmental Science University of PortsmouthPortsmouthUK

Granulitic lunar meteorites offer rare insights into the timing and nature of igneous,metamorphic and impact processes in the lunar *** dating the different events recorded by these materials is very challenging,however,due to low trace elem.nt abundances (***,nd,Lu,Hf),rare micrometerscale U-Th-bearing accessory minerals,and disturbed Ar-Ar systematics following a multi-stage history of shock and thermal *** we report on micro-baddeleyite grains in granulitic mafic breccia nWA 3163 for the first time and show that targeted microstructural analysis (electron backscatter diffraction) and nanoscale geochronology (atom probe tomography) can overcome these barriers to lunar chronology.A twinned (-90°/) baddeleyite domain yields a 232Th/208Pb age of 4328 ± 309 ma,which overlaps with a robust secondary ion mass spectrometry (SimS) 207Pb/206Pb age of 4308± 18.6 ma and is interpreted here as the crystallization age for the igneous protolith of nWA 3163.A second microstructural domain,mm in width,contains patchy overprinting baddeleyite and yields a Th-Pb age of 2175± 143 ma,interpreted as dating the last substantial impact event to affect the *** finding dem.nstrates the potential of combining microstructural characterization with nanoscale geochronology when resolving complex P-T-t histories in planetary materials,here yielding the oldest measured crystallization age for components of lunar granulite nWA 3163 and placing further constraints on the formation and evolution of lunar crust.

关键词： Baddeleyite U-Th-Pb isotopes EBSD Atom probe tomography Geochronology northwest Africa 3163

射箭运动员在多次重复发射过程中电活性的动态

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首都体育学院学报 2015年第2期27卷 97-100页

作者： И·Н·布恰茨卡娅 Р·М·戈罗德尼切夫国立大卢基体育运动研究院大卢基市

剧烈运动会导致机体功能潜力的下降和疲劳的累积,而在不同类型肌肉工作中,疲劳过程是在中枢机制和外周机制的参与下发展的。特定机制的优势取决于动作结构及完成该动作的持续时间和强度。疲劳引起生理学功能暂时的不协调,工作的量化指... 详细信息

剧烈运动会导致机体功能潜力的下降和疲劳的累积,而在不同类型肌肉工作中,疲劳过程是在中枢机制和外周机制的参与下发展的。特定机制的优势取决于动作结构及完成该动作的持续时间和强度。疲劳引起生理学功能暂时的不协调,工作的量化指标和质性指标的恶化,提高了其生理学代价。射箭比赛活动是在若干小时中持续静态和动态活动的交替、相对单一形式的工作。研究射箭运动员在完成模拟比赛活动的射箭练习中的肌肉电活性。在对射箭练习的视频资料进行评定的基础上,研究人员将射箭结构划分为各个工作时相,每一个时相的开始和结束时刻都带有明显的界限。射箭的时间参数与记录的被研究肌群电活性的同步化使得能对技术上最重要发射时相进行精细的肌电图像分析。射箭运动员的肌肉提供多次射箭运动的电活性特征的实验数据,是首次明确界定"主导"肌群在射箭运动中技术上的重要时相的具体实施。

关键词：射箭肌肉电活性的幅度和频率 “主导”肌群疲劳