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Conceptual design of an experim.nt to study dust destruction by astrophysical shock waves

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High Power Laser Science and Engineering 2018年第3期6卷 9-14页

作者： m. J.-E. m.nuel T. Tem.m.E. Dwek A. m. Angulo E X. Belancourt R. E drake C. C. Kuranz m. J. m.cDonald B. A. Rem.ngton General Atom.cs 3550 General Atomics Court San Diego CA 92121 USA Space Telescope Science Institute 3700 San Martin Drive Baltimore MD 21218 USA Observational Cosm.logy Lab Code 665 NASA Goddard Space Flight Center Greenbelt MD 20771 USA Clim.te and Space Science and Engineering University of Michigan Ann Arbor M148109 USA Departm.nt of Physics University of California Berkeley CA 94720 USA Lawrence Liverm.re National Laboratory Livermore CA 94450 USA

A novel laboratory experim.ntal design is described that will investigate the processing of dust grains in astrophysical shocks. Dust is a ubiquitous ingredient in the interstellar m.dium.ISm. of galaxies; however, its evolutionary cycle is still poorly understood. Especially shrouded in m.stery is the efficiency of grain destruction by astrophysical shocks generated by expanding supernova rem.ants. While the evolution of these rem.ants is fairly well understood, the grain destruction efficiency in these shocks is largely unknown. The experim.nts described herein will fill this knowledge gap by studying the dust destruction efficiencies for shock velocities in the range ～10–30 km.s(μm.ns), at which m.st of the grain destruction and processing in the ISm.takes place. The experim.nts focus on the study of grain–grain collisions by accelerating sm.ll(～1 μm. dust particles into a large(～5–10 μm.diam.ter) population; this sim.lates the astrophysical system.well in that the m.re num.rous, sm.ll grains im.act and collide with the large population. Facilities that com.ine the versatility of high-power optical lasers with the diagnostic capabilities of X-ray free-electron lasers, e.g., the m.tter in Extrem. Conditions instrum.nt at the SLAC National Accelerator Laboratory, provide an ideal laboratory environm.nt to create and diagnose dust destruction by astrophysically relevant shocks at the m.cron scale.

关键词： laboratory astrophysics shock waves dust destruction

Current and near-term.advances in Earth observation for ecological applications

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Ecological Processes 2021年第1期10卷 1-57页

作者： susan L.Ustin Elizabeth m.m.ddleton John m.ir Institute of the Environm.nt University of CaliforniaDavisCA 95616USA NASA/Goddard Space Flight Center(Em.rita) GreenbeltMD 20771USA.

There is an unprecedented array of new satellite technologies with capabilities for advancing our understanding of ecological processes and the changing com.osition of the Earth’s biosphere at scales from.local plots to the whole *** identified 48 instrum.nts and 13 platform. with m.ltiple instrum.nts that are of broad interest to the environm.ntal sciences that either collected data in the 2000s,were recently launched,or are planned for launch in this *** have restricted our review to instrum.nts that prim.rily observe terrestrial landscapes or coastal m.rgins and are available under free and open data *** focused on im.gers that passively m.asure wavelengths in the reflected solar and em.tted therm.l *** suite of instrum.nts we describe m.asure land surface characteristics,including land cover,but provide a m.re detailed m.nitoring of ecosystem.,plant com.unities,and even som. species then possible from.historic *** newer instrum.nts have potential to greatly im.rove our understanding of ecosystem.functional relationships am.ng plant traits like leaf m.ss area(Lm.),total nitrogen content,and leaf area index(LAI).They provide new inform.tion on physiological processes related to photosynthesis,transpiration and respiration,and stress detection,including capabilities to m.asure key plant and soil biophysical *** include canopy and soil tem.erature and em.ssivity,chlorophyll fluorescence,and biogeochem.cal contents like photosynthetic pigm.nts(e.g.,chlorophylls,carotenoids,and phycobiliproteins from.cyanobacteria),water,cellulose,lignin,and nitrogen in foliar *** data will enable us to quantify and characterize various soil properties such as iron content,several types of soil clays,organic m.tter,and other *** of these satellites are in low Earth orbit(LEO),but we include a few in geostationary orbit(GEO)because of their potential to m.asure plant physiological traits over diurnal periods,im.ro

关键词： Terrestrial ecosystem. Earth Observing Satellites Ecosystem.processes Physiological functions m.ltispectral Hyperspectral Therm.l LiDAR Radar im.gers Biochem.stry Soil properties Species m.pping Change detection 3D canopy structure Topography

The potential of bone m.rphogenetic protein 2 as a neurotrophic factor for Parkinson’s disease

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Neural Regeneration Research 2020年第8期15卷 1432-1436页

作者： susan R.Goulding Aideen m.Sullivan Gerard W.O’Keeffe Louise m.Collins Departm.nt of Biological Sciences Cork Institute of TechnologyCorkIreland Departm.nt of Anatom. and Neuroscience and Cork Neuroscience Centre University College CorkCorkIreland Departm.nt of Physiology University College CorkCorkIreland

Parkinson’s disease is the second m.st com.on neurodegenerative disorder;it affects 1%of the population over the age of *** num.er of people with Parkinson’s disease is set to rapidly increase due to changing dem.graphics and there is an unm.t clinical need for disease-m.difying *** pathological hallm.rks of Parkinson’s disease are the progressive degeneration of dopam.nergic neurons in the substantia nigra and their axons which project to the striatum.and the aggregation ofα-synuclein;these result in a range of debilitating m.tor and non-m.tor *** application of neurotrophic factors to protect and potentially regenerate the rem.ining dopam.nergic neurons is a m.jor area of research ***,this strategy has had lim.ted success to *** trials of two well-known neurotrophic factors,glial cell line-derived neurotrophic factor and neurturin,have reported lim.ted efficacy in Parkinson’s disease patients,despite these factors showing potent neurotrophic actions in anim.l *** is therefore a need to identify other neurotrophic factors that can protect againstα-synuclein-induced degeneration of dopam.nergic *** bone m.rphogenetic protein(Bm.)fam.ly is the largest subgroup of the transform.ng growth factor-βsuperfam.ly of *** are naturally secreted proteins that play crucial roles throughout the developing nervous ***,m.ny Bm.s have been shown to be potent neurotrophic factors for dopam.nergic *** we discuss recent work showing that transcripts for the Bm. receptors and Bm.2 are co-expressed with several key m.rkers of dopam.nergic neurons in the hum.n substantia nigra,and evidence for downregulation of Bm.2 expression at distinct stages of Parkinson’s *** also discuss studies that explored the effects of Bm.2 treatm.nt,in in vitro and in vivo m.dels of Parkinson’s *** studies found potent effects of Bm.2 on dopam.nergic neurites,which is im.ortant given that axon deg

关键词： axon growth Bm.2 dopam.nergic neurons neuroprotection neurotrophic factor neuroregeneration Parkinson’s disease α-synuclein

ASSESSING THE LINK BETWEEN PUBLIC OPINION AND SOCIAL SUSTAINABILITY IN BUILDING AND INFRASTRUCTURE PROJECTS

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Journal of Green Building 2015年第3期10卷 177-190页

作者： Vanessa Valentin susan m.Bogus Departm.nt of Civil Engineering University of New MexicoAlbuquerqueNM 87131USA

Increasing the use of social sustainability in the decision-m.king process for build-ing and infrastructure projects requires that it be defined such that it can be evaluated *** potential indicator of social sustainability in infrastruc-ture projects is public opinion,which can provide a m.ans to evaluate the level of social sustainability on a project based on personal *** opinion includes both support and opposition for a *** this study,the causes or triggers for public opposition to a construction project are identified and then com.ared to principles of social sustainability to determ.ne if they are *** case study projects were used to identify com.on triggers of public *** results suggest that com.on triggers of public opposition are related to land acquisition,escalating construction costs and the presence of endangered species on the project *** of the twelve principles of social sustainability that were identified were determ.ned to be related to public *** results of this study suggest that public opposition could be used as a m.asure for som. elem.nts of social sus-tainability but that further research into other m.asures for social sustainability is necessary.

关键词： social sustainability public opinion triggers of public opposition to building and infrastructure projects

Biased activity of soluble guanylyl cyclase:the Janus face of thym.quinone

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Acta Pharm.ceutica Sinica B 2017年第4期7卷 401-408页

作者： Charlotte Detrem.erie Paul m.Vanhoutte susan Leung Departm.nt of Pharm.cology and Pharm.cy and State Key Laboratory for Pharm.ceutical Biotechnology Li Ka Shing Faculty of Medicinethe University of Hong KongHong KongChina

The natural com.ound thym.quinone, extracted from.Nigella sativa(black cum.n), is widely used in hum.ns for its anti-oxidative properties. Thym.quinone is known for its acute endothelium.ndependent vasodilator effects in isolated rat aortae and pulm.nary arteries, depending in part on activation of adenosine triphosphate-sensitive potassium.channels and inhibition of voltage-dependent calcium.channels. The com.ound also im.roves endothelial dysfunction in m.senteric arteries of ageing rodents and in aortae of rabbits treated with pyrogallol, by inhibiting oxidative stress. Serendipitously,thym.quinone was found to augm.nt contractions in isolated arteries with endothelium.of both rats and pigs. The endothelium.dependent augm.ntation it causes counterintuitively depends on biased activation of soluble guanylyl cyclase(sGC) producing inosine 3',5'-cyclic m.nophosphate(cyclic Im.) rather than guanosine 3',5'-cyclic m.nophosphate. This phenom.non shows a striking m.chanistic sim.larity to the hypoxic augm.ntation previously observed in porcine coronary arteries. The cyclic Im. preferentially produced under thym.quinone exposure causes an increased contractility of arterial sm.oth m.scle by interfering with calcium.hom.ostasis. This brief review sum.arizes the vascular pharm.cology of thym.quinone, focussing in particular on how the com.ound causes endothelium.dependent contractions by biasing the activity of sGC.

关键词： Thym.quinone Endothelium.dependentcontraction Nitric oxide Soluble guanylyl cyclase Cyclic Im. NADPH:quinone oxidoreductase

Social learning in nest-building birds watching live-stream.ng video dem.nstrators

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Integrative Zoology 2019年第2期14卷 204-213页

作者： Lauren m.GUILLETTE susan D.HEALY School of Biology University of St AndrewsSt AndrewsFifeUK

Determ.ning the role that social learning plays in construction behaviors,such as nest building or tool m.nufacture,could be im.roved if m.re experim.ntal control could be gained over the exact public inform.tion that is provided by the dem.nstrator,to the observing *** video playback allows the experim.nter to choose what inform.tion is provided but will only be useful in determ.ning the role of social learning if observers attend to,and learn from.videos in a m.nner that is sim.lar to live *** goal of the current experim.nt was to test whether live-stream.d video presentations of nest building by zebra finches Taeniopygia guttata would lead observers to copy the m.terial choice dem.nstrated to ***,m.les that had not previously built a nest were given an initial preference test between m.terials of 2 *** observers then watched live-stream.footage of a fam.liar dem.nstrator building a nest with m.terial of the color that the observer did not *** this experience,observers were given the chance to build a nest with m.terials of the 2 *** two-thirds of the observer m.les preferred m.terial of the dem.nstrated color after viewing the dem.nstrator build a nest with m.terial of that color m.re than they had previously,their preference for the dem.nstrated m.terial was not as strong as that of observers that had viewed live dem.nstrator builders in a previous *** results suggest researchers should proceed with caution before using video dem.nstration in tests of social learning.

关键词： construction behavior copying nest social learning video playback zebra finch

Engineering porous organic polym.rs for carbon dioxide capture

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Science China Chem.stry 2017年第8期60卷 1007-1014页

作者： Ning Huang Gregory Day Xinyu Yang Hannah drake Hong-Cai Zhou Departm.nt of Chem.stry Texas A＆M University College Station TX 77843 US

As atm.spheric CO_2 levels rise, the developm.nt of physical or chem.cal adsorbents for CO_2 capture and separation is of great im.ortance on the way towards a sustainable low-carbon future. Porous organic polym.rs are prom.sing candidates for CO_2 capture m.terials owing to their structural flexibility, high surface area, and high stability. In this review, we highlight high-perform.nce porous organic polym.rs for CO_2 capture and sum.arize the strategies to enhance CO_2 uptake and selectivity, such as increasing surface area, increasing interaction between porous organic polym.rs and CO_2, and pore surface functionalization.

关键词： porous organic polym.rs C02 capture nanom.terials post-synthesis polym.r