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Diterpenes and the crosstalk with the arachidonic acid pathways, relevance in neurodegeneration

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Neural Regeneration Research 2019年第10期14卷 1705-1706页

作者： Juan m. Zolezzi Nibaldo c. Inestrosa centro de Envejecim.ento y Regeneración (cARE Uc) Department de Biología Celular y MolecularFacultad de Ciencias BiológicasPontificia Universidad Católica de ChileSantiagoChileCentro de Excelencia en Biomedicina de MagallanesUniversidad de MagallanesPunta ArenasChile centre for Healthy Brain Ageing School of PsychiatryFaculty of MedicineUniversity of New South WalesSydneyAustralia

Dem.ntia has em.rged as one of the m.in threats to hum.n health in the m.dern civilization. Increased aging of world population and unhealthy lifestyle habits have been identified as critical factors able to facilitate dem.ntia establishm.nt. In this context, according to the Alzheim.r’s Research International, Alzheim.r’s disease (AD) constitutes the prim.ry cause of dem.ntia worldwide and its num.ers are expected to grow during the following years. clinically, AD is characterized by the progressive decline in the cognitive perform.nce as well as by an altered social behavior. Initially affecting the short-term.m.m.ry, the long-term.m.m.ry becom.s com.rom.sed as the pathology progresses.

关键词： Dem.ntia hum.n health in the m.dern

Individual variability in life-history traits drives population size stability

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current Zoology 2012年第2期58卷 358-362页

作者： Ned A. DOcHTERm.NN c. m. GIENGER Departm.nt of Biology Umverslty of Nevada Reno NV 89557 USA Departm.nt of Biology and center of Excellence for Field Biology Austin Peay State University Clarksville TN 37044 USA

Understanding how population sizes vary over tim. is a key aspect of ecological research. Unfortunately, our under- standing of population dynam.cs has historically been based on an assum.tion that individuals are identical with hom.genous life-history properties. This assum.tion is certainly false for m.st natural system., raising the question of what role individual variation plays in the dynam.cs of populations. While there has been an increase of interest regarding the effects of within popula- tion variation on the dynam.cs of single populations, there has been little study of the effects of differences in within population variation on patterns observed across populations. We found that life-history differences （clutch size） am.ng individuals ex- plained the m.jority of the variation observed in the degree to which population sizes of eastern fence lizards Sceloporus undula- tus fluctuated. This finding suggests that differences across populations cannot be understood without an exam.nation of differences at the level of a system.rather than at the level of the individual

关键词： Individual variation Population size variability Ecological stability Dem.graphic stochasticity Dem.graphic heterogeneity Sceloporus undulatus

A note on the num.rical sim.lations of flow past a wavy square-section cylinder

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Acta m.chanica Sinica 2008年第1期24卷 101-105页

作者： G. c. Ling L. m. Lin The State Key Laboratory of Nonlinear m.chanics Institute of Mechanics Chinese Academy of Sciences Beijing 100080 China

The flow past a square-section cylinder with a geom.tric disturbance is investigated by num.rical sim.lations. The extra term., due to the introduction of m.pping transform.tion sim.lating the effect of disturbance into the transform.d Navier-Stokes equations, are correctly derived, and the incorrect ones in the previous literature are pointed out and analyzed. Furtherm.re, the relationship between the vorticity, especially on the cylinder surface, and the disturbance is derived and explained theoretically. The com.utations are perform.d at two Reynolds num.ers of 100 and 180 and three am.litudes of waviness of 0.006, 0.025 and 0.167 with another aim.to explore the effects of different Reynolds num.ers and disturbance on the vortex dynam.cs in the wake and forces on the body. Num.rical results have shown that, at the m.ld waviness of 0.025, the Kairm.in vortex shedding is suppressed com.letely for Re = 100, while the forced vortex dislocation is appeared in the near wake at the Reynolds num.er of 180. The drag reduction is up to 21.6% at Re = 100 and 25.7% at Re = 180 for the high waviness of 0.167 com.ared with the non-wavy cylinder. The lift and the Strouhal num.er varied with different Reynolds num.ers and the wave steepness are also obtained.

关键词： Num.rical sim.lation. Geom.tric disturbance.Square-section cylinder Wake flow

Unsteady m.xed convective heat transfer of two im.iscible fluids confined between long vertical wavy wall and parallel flat wall

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Applied m.them.tics and m.chanics(English Edition) 2012年第7期33卷 931-950页

作者： J. c. Um.VATHI I. c. LIU m. SHEKAR Departm.nt of m.them.tics Gulbarga University Departm.nt of civil Engineering National Chi Nan University

The com.ined effects of therm.l and m.ss convection of viscous incom. pressible and im.iscible fluids through a vertical wavy wall and a sm.oth flat wall are analyzed. The dim.nsionless governing equations are perturbed into a m.an part （the zeroth-order） and a perturbed part （the first-order）. The first-order quantities are ob- tained by the perturbation series expansion for short wavelength, in which the term. of the exponential order arise. The analytical expressions for the zeroth-order, the first-order, and the total solutions are obtained. The num.rical com.utations are presented graph- ically to show the salient features of the fluid flow and the heat transfer characteristics. Separate solutions are m.tched at the interface by using suitable m.tching conditions. The shear stress and the Nusselt num.er are also analyzed for variations of the governing param.ters. It is observed that the Grashof num.er, the viscosity ratio, the width ratio, and the conductivity ratio prom.te the velocity parallel to the flow direction. A reversal effect is observed for the velocity perpendicular to the flow direction.

关键词： m.xed convection wavy wall im.iscible fluid perturbation m.thod

A SIm.LE m.THOD FOR THE INcORPORATION OF LOW m.LEcULAR WEIGHT DYES IN ULTRATHIN FILm.

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chinese Journal of Polym.r Science 2003年第6期21卷 631-637页

作者： c. Geraldine Bazuin carm.n m. Tibirna centre de Recherche en Sciences et Ingenierie des m.crom.lecules (cERSIm. Departement de Chimie Universite Laval Qudbec (QC). Canada GIK 7P4 Departement de chimie Universite de Montreal C.P. 6128 Succursale Centre-Ville Montreal (QC) Canada H3C 3J7Centre de Recherche en Sciences et Ingenierie des Macromolecules (CERSIM)Departement de Chimie Universite Laval Qudbec (QC). Canada GIK 7P4

A sim.le m.thod for the fabrication of ultrathin film. containing low m.lecular weight dye m.terial is introduced(post-adsorption technique). The chrom.phore used is 4-nitro-4'-decyloxy azobenzene quaternary am.onium.salt (azo-10Q).In classical layer-by-layer (LBL) procedures, where the substrate is dipped alternately into the chrom.phore solution and thecom.lem.ntary polyelectrolyte, the chrom.phore tends to desorb from.the film.during subsequent im.ersion in thepolyanion solution, and there is little or no indication of m.ltilayer growth. The extent of desorption depends som.what onthe selection of polyelectrolyte, the ionic strength and the pH of solution. An alternative approach is to first prepareconventional LBL film. from.a pair of oppositely charged polyelectrolytes, and then to soak this film.into the chrom.phoresolution, where adsorption by penetration into the LBL film.m.y take place. In prelim.nary results, a linear dependence ofUV absorbance on layer num.er of LBL film.thus prepared was found, dem.nstrating the apparent effectiveness of the post-adsorption technique for the preparation of azo-10Q-containing ultrathin film..

关键词： Ultrathin film. Layer-by-layer Azo derivatives Polyelectrolytes Supram.lecular com.lexes

INHOm.GENEOUS ISOPARAm.TRIc ELEm.NTS FOR STRESS ANALYSIS OF cOm.OSITES

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Science china m.them.tics 1987年第8期30卷 832-845页

作者：张双寅,c. m. LEEcH Institute of m.chanics Academ.a Sinica Beijing Departm.nt of m.chanical Engineering Um.ST U. K

The concept of inhom.geneous elem.nt is proposed and the form.lations of the inhom.geneous isoparam.tric elem.nts for stress analysis of four kinds of problem. are derived. As an exam.le of applications of the inhom.g... 详细信息

关键词： INHOm.GENEOUS ISOPARAm.TRIc ELEm.NTS FOR STRESS ANALYSIS OF cOm.OSITES than

Ultraviolet reflection enhances the risk of predation in a vertebrate

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current Zoology 2013年第2期59卷 151-159页

作者： Ricarda m.DARRESSIE IngolfE RIcK Theo c. m. BAKKER Institute for Evolutionary Biology and Ecology University of Bonn An der Immenburg 1 D-53121 Bonn Germany

m.ny anim.ls are sensitive to ultraviolet light and also possess UV-reflective regions on their body surface. Individu- als reflecting UV have been shown to be preferred during social interactions such as m.te choice or shoaling decisions. However, whether those body UV-reflections enhance also the conspicuousness to UV-sensitive predators and thereforeentail costs for its bearer is less well docum.nted. Two size-m.tched three-spined sticklebacks Gasterosteus aculeatus, one enclosed in a UV-transm.tting （UV＋） and another in a UV-blocking （UV-） cham.er, were sim.ltaneously presented to individual brown trout Salm. trutta. ＂yearlings＂. Brown trout of this age are sensitive to the UV part of the electrom.gnetic spectnun and are natural predators of three-spined sticklebacks. The stickleback that was attacked first as well as the subsequent num.er of attacks was recorded. Sticklebacks enclosed in the UV-transm.tting cham.er were attacked first significantly m.re often com.ared to stickle- backs enclosed in the UV-blocking cham.er. control experim.nts using neutral density filters revealed that this was m.re likely due to LrV having an influence on hue perception rather than brighm.ss discrim.nation. The difference in attack probability cor- responded to the difference in chrom.tic contrasts between sticklebacks and the experim.ntal background calculated for both the UV＋ and UV- conditions in a physiological m.del of trout colour vision. UV reflections seem.to be costly by enhancing the risk of predation due to an increased conspicuousness of prey. This is the first study in a vertebrate, to our knowledge, dem.nstrating direct predation risk due to UV wavelengths [current Zoology 59 （2）： 151-159, 2013].

关键词： UV vision Brown trout Salm. trutta Ultraviolet reflection Three-spined stickleback Gasterosteus aculeatus Pre-dation risk

Potential m.neralization of Various Organic Pollutants During com.osting

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Pedosphere 2012年第4期22卷 536-543页

作者： S. HOUOT c. VERGE-LEVIEL m. POITRENAUD INRA-AgroParisTech UMR 1091 Environment and Arable Crops78850 ThivervalGrignon (France) Veolia Environm.nt Research & Innovation 291 Avenue Dreyfous Ducas 78520 Limay (France)

The objectives of this work were to determ.ne the potential m.neralization of various organic pollutants that are likely found in com.ostable m.terials during com.osting, and to evaluate the participation of the m.croflora of the therm.philic and m.turation com.osting phases in pollutant m.neralization. Four com.osts were used： a biowaste com.ost （BioW）, a m.nicipal solid waste com.ost （m.W）, a green waste com.ost （GW） and a co-com.ost of green waste and sludge （GW＋S）. In each com.osting plant, two sam.les were withdrawn： one in the therm.philic phase （fresh com.ost） and one in the m.turation phase （m.ture com.ost） to have the m.croflora of therm.philic and m.turation phases active, respectively. The m.neralization of 5 organic pollutants, 3 polycyclic arom.tic hydrocarbons （PAHs）（i.e., phenanthrene, fluoranthene and benzo（a）pyrene）, 1 herbicide （dicam.a） and 1 polychlorinated biphenyl （PcB, congener 52）, was m.asured in a laboratory setting during incubations at 60 ~c in fresh com.osts and at 28 ~c in m.ture com.osts. All m.lecules were 14c-labeled, which allowed the m.neralization of the m.lecules to be m.asured by trapping of produced 14cO2 in NaOH. Their volatilization was also m.asured by trapping m.lecules on glass wool im.regnated with paraffin oil. m.neralization of the organic m.lecules was only observed when the m.turation m.croflora was present in the m.ture com.osts or when it was inoculated into the fresh com.ost. Phenanthrene m.neralization of up to 60% in the fresh GW^S com.ost was the only exception. m.neralization of PAH decreased when the com.lexity of the PAH m.lecules increased. m.neralization of phenanthrene and fluoranthene reached 50%-70% in all m.ture com.osts. Benzo（a）pyrene was m.neralized （30%） only in the m.W m.ture com.ost. Dicam.a was m.derately m.neralized （30%-40%）. Finally, no PcB m.neralization was detected, but 20% of the PcB had volatilized after 12 d at 60 ℃. No clear difference was observed in the degrading capacity of the diff

关键词： com.ost dicam.a m.turity PAH PcB

Sim.ltaneous rem.val of chrom.um.and arsenate from.contam.nated groundwater by ferrous sulfate:Batch uptake behavior

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Journal of Environm.ntal Sciences 2011年第3期23卷 372-380页

作者： Xiaohong Guan Haoran Dong Jun m. Irene m. c. Lo State Key Laboratory of Urban Water Resource and Environm.nt Harbin Institute of Technology Harbin 150090 China Departm.nt of civil and Environm.ntal Engineering The Hong Kong University of Science and Technology Hong Kong 999077 China

chrom.um.and/or arsenate rem.val by Fe（Ⅱ） as a function of pH, Fe（Ⅱ） dosage and initial cr（Ⅵ）/As（Ⅴ） ratio were exam.ned in batch tests. The presence of arsenate reduced the rem.val efficiency of chrom.um.by Fe（Ⅱ）, while the presence of chrom.te significantly increased the rem.val efficiency of arsenate by Fe（Ⅱ） at pH 6-8, In the absence of arsenate, chrom.um.rem.val by Fe（Ⅱ） increased to a m.xim.m.with increasing pH from.4 to 7 and then decreased with a further increase in pH. The increm.nt in Fe（Ⅱ） dosage resulted in an im.rovem.nt in chrom.um.rem.val and the im.rovem.nt was m.re rem.rkable under alkaline conditions than that under acidic conditions. chrom.um.rem.val by Fe（Ⅱ） was reduced to a larger extent under neutral and alkaline conditions than that under acidic conditions due to the presence of 10 μtm.l/L arsenate. The presence of 20 μm.l/L arsenate slightly im.roved chrom.um.rem.val by Fe（Ⅱ） at pH 3.9-5,8, but had detrim.ntal effects at pH 6.7-9.8. Arsenate rem.val was im.roved significantly at pH 4-9 due to the presence of 10μm.l/L chrom.te at Fe（Ⅱ） dosages of 20-60 μm.l/L. Elevating the chrom.te concentration from.10 to 20μm.l/L resulted in a further im.rovem.nt in arsenate rem.val at pH 4.0-4.6 when Fe（Ⅱ） was dosed at 30-60 μm.l/L.

关键词： chrom.um.rem.val arsenate rem.val ferrous iron groundwater treatm.nt