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Nano research 2009年第12期2卷 945-954页

作者： Hongming Wang Servaas Michielssens Samuel L.c.Moors Arnout ceulemans Laboratory of Quantum chemistry Department of Chemistry and INPAC Institute for Nanoscale Physics and ChemistryKatholieke Universiteit LeuvenBelgium

Single-walled c.r.on nanotubes(SWNTs)are possible nano-injectors and delivery vehicles of molecular probes and drugs into *** order to explore the interaction between lipid membranes and c.r.on nanotubes,we investigate the binding mechanism of dipalmitoylphosphatidylcholine(DPPc)with SWNTs by molecular *** low concentration range simulations,the DPPc molecules form a supramolecular two-layered cylindrical structure wrapped around the c.r.on nanotube *** hydrophobic part of DPPc is adsorbed on the surface of the nanotube,and the hydrophilic top is oriented towards the aqueous *** higher concentration ranges,the DPPc molecules are found to form a supramolecular multi-layered structure wrapped around the c.r.on nanotube *** the saturation point a membrane-like structure is self-assembled with a width of 41.4Å,which is slightly larger than the width of a cell *** study sheds light on the existing confl icting simulation data on adsorption of single-chained phospholipids.

关键词： cell membrane molecular dynamics c.r.on nanotubes self-assembly nano-injector

Stem cells for c.r.iac.r.pair: an introduction

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Journal of Geriatric c.r.iology 2013年第2期10卷 186-197页

作者： Bastiaan c du Pr(e) Pieter A Doevendans Linda W van Laake Departments of c.r.iology and Medical Physiology Division of Heart and Lungs University Medical Center Utrecht P.O. box 85500 3508 GA Utrecht the Netherlands Departments of c.r.iology and Medical Physiology Division of Heart and Lungs University Medical Center Utrecht P.O. box 85500 3508 GA Utrecht the Netherlands Inter university Cardiology Institute of the Netherlands P.O. box 19258 2501 DG Utrecht the Netherlands Departments of c.r.iology and Medical Physiology Division of Heart and Lungs University Medical Center Utrecht P.O. box 85500 3508 GA Utrecht the Netherlands Hubrecht Institute P.O box 85164 3508 AD Utrecht the Netherlands

c.r.iovascular disease is a major cause of morbidity and mortality throughout the world. Most c.r.iovascular diseases, such as ischemic heart disease and c.r.iomyopathy, are associated with loss of functional c.r.iomyocytes. Unfortunately, the heart has a limited regenerative capacity and is not able to replace these c.r.iomyocytes once lost. In recent years, stem cells have been put forward as a potential source for c.r.iac.r.generation. Pre-clinical studies that use stem cell-derived c.r.iac cells show promising results. The mechanisms,though, are not well understood, results have been variable, sometimes transient in the long term, and often without a mechanistic *** are still severalmajor hurdles to be taken. Stem cell-derived c.r.iac cells should resemble original c.r.iac cell types and be able to integrate in the damaged heart. Integration requires administration of stem cell-derived c.r.iac cells at the right time using the right mode of delivery. Once delivered, transplanted cells need vascularization, elec.r.physiological coupling with the injured heart, and prevention of immunological rejection. Finally, stem cell therapy needs to be safe, reproducible, and affordable. In this review, we will give an introduction to the principles of stem cell based c.r.iac.r.pair.

关键词： c.r.iomyocytes Heart regeneration Stem cell

A metal-free composite photocatalyst of graphene quantum dots deposited on red phosphorus

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Journal of Environmental Sciences 2017年第10期29卷 91-97页

作者： Donald K.L.chan Jimmy c.Yu Yecheng Li Zhuofeng Hu Department of chemistry The Chinese University of Hong Kong Shatin New Territories Shenzhen research Institute The Chinese University of Hong Kong

A simple approach to enhance the photocatalytic activity of red phosphorus（P） was developed.A mechanical ball milling method was applied to reduce the size of red P and to deposit graphene quantum dots onto red P. The product was characterized by scanning elec.r.n microscopy, transmission elec.r.n microscopy, contact angle measurements, zeta-potential measurements, X-ray diffraction and UV–vis absorption spec.r.scopy. The product exhibited high visible-light-driven photocatalytic performance in the photodegradation of rhodamine B.

关键词： Metal-free photocatalyst Graphene quantum dots red phosphorus Mechanical ball milling

ISOPErIMETrIc PrOBLEMS OF THE cALcULUS OF VArIATIONS WITH FrAcTIONAL DErIVATIVES

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Acta Mathematica Scientia 2012年第2期32卷 619-630页

作者： ric.r.o Almeida rui A.c.Ferreira Delfim F.M.Torres center for research and Development in Mathematics and Applications Department of MathematicsUniversity of Aveiro3810-193 AveiroPortugal Department of Mathematics Faculty of Engineering and Natural SciencesLusophone University of Humanities and Technologies1749-024 LisbonPortugal

In this article, we study isoperimetric problems of the calculus of variations with left and right riemann-Liouville fractional derivatives. Both situations when the lower bound of the variational integrals coincide a... 详细信息

关键词： calculus of variations fractional derivatives isoperimetric problems

NUMErIcAL SIMULATION OF SUccINONITrITE DENDrITIc GrOWTH IN A FOrcED FLOW

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Acta Metallurgica Sinica(English Letters) 2008年第6期21卷 444-450页

作者： Z. chen c.L. chen L.M. Hao School of Science Department of Applied Physics Shaanxi Key Laboratory of Condensed Matter Structures and Properties Northwestern Polytechnical University Xi＇an 710072 China School of Science Xi＇an University of Science ＆ Technology Xi＇an 710054 China

Numerical simulation based on phase field method is performed to describe solidification process of pure material in a free or forced flow. The evolution of the interface is showed, and the effects of mesh grid and flow velocity on succinonitrite shape are studied. These results indicate that crystal grows into an equiaxial dendrite in a free flow and into an asymmetrical dendritic in a forced flow. With increasing flow velocity, the upstream dendritic arm tip grows faster and the downstream arm grows slower. However, the evolution of the perpendicular tip has no significant change. In addition, mesh grid has no influence on dendritic growth shape when mesh grid is above 300×300.

关键词： Phase field method Forced flow Dendritic Succinonitrite Tip velocity

Titanate Nanorods Modified with Nanocrystalline ZnS Particles and Their Photocatalytic Activity on Pollutant removal

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Journal of Materials Science & Technology 2016年第11期32卷 1122-1128页

作者： G.Naudin T.Entradas B.Barrocas O.c.Monteiro Faculte de chimie Universite Pierre et Marie Curie (UPMC) Batiment F 3e etage 4 placeJussieu 75005 Paris France centro de Quimica e Bioquimica Faculdade de Ciencias Universidade de Lisboa 1749-016 Lisboa Portugal

Aiming to produce materials with enhanced photocatalytic properties, the synthesis of new crystalline nanocomposites by combining titanate nanorods（TNr） with ZnS nanocrystallites is described in this *** TNr modification was accomplished by an in situ nucleation and growth process of ZnS *** diethyldithioc.r.amate was used as the metal chalcogenide prec.r.or. The prepared materials were structural, morphological and optical characterized by X-ray diffraction, transmission elec.r.n microscopy and high resolution transmission elec.r.n microscopy, energy dispersive spec.r.scopy and powder diffuse reflectance spec.r.. crystalline Zn S nanoparticles were obtained as a homogeneous and continuous layer, covering completely the TNr surface. The application of these new nanocomposite materials on photocatalytic degradation of pollutants was investigated. First, the evaluation of hydroxyl radical formation, using the terephthalic acid as probe, was studied. Afterwards, the adsorption and photodegradation of safranine-T, used here as a model pollutant molecule, was investigated. The obtained data indicate that the prepared nanocomposites have potential to be used as photocatalysts for organic pollutant *** best removal results（97% removal） were obtained using the 0.01 Zn S/HTNr sample as catalyst（0.2 g/L; 10 ppm safranin-T solution） with a combination of a low dye adsorption（20%） and a high dye photocatalytic degradation（77%）.

关键词： Nanocomposite materials Surface modification Photocatalysis Adsorption ability Optical properties

Myosin XI Is required for Actin-Associated Movement of Plastid Stromules

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Molecular Plant 2009年第6期2卷 1262-1272页

作者： Senthil Kumar A. Natesan James A. Sullivan John c. Gray Department of Plant Sciences University of Cambridge Downing Street Cambridge CB2 3EA UK Present address: Sir William Dunn School of Pathology University of Oxford South Parks Road Oxford OX1 3RE UK Present address: School of Biological and chemical Sciences Queen Mary University of London Mile End Road London E1 4NS UK

Stromules are highly dynamic stroma-filled tubules extending from the surface of plastids and occasionally interconnecting individual plastids, allowing the movement of complex biological molecules between the interconnected plastids. Experiments with inhibitors of cytoskeleton assembly have indicated the involvement of an actin-based system in stromule movement. However, the motor protein associated with the system had not been identified. Here, we present direct evidence that myosin XI is involved in the formation and movement of stromules in tobacco leaves. Application of 2,3-butanedione 2-monoxime, an inhibitor of myosin ATPase activity, resulted in the loss of stromules from tobacco leaf epidermal cells. Transient rNA interference of myosin XI in leaves of Nicotiana benthamiana also resulted in the loss of stromules from epidermal cells, without any effect on transcripts for actin or myosin VIII. Transient expression of a GFP- tagged myosin XI tail domain in tobacco leaf epidermal cells showed that the fusion protein localized to the chloroplast envelope, as well as to mitochondria and other organelles. Our findings identify myosin XI as a key protein involved in the formation and movement of stromules.

关键词： chloroplast biology cytoskeleton organelle biogenesis/function tobacco.

Assessing the thermal stability of toolmarks casting materials through optical comparison microscopy,virtual comparison microscopy and quantitative similarity sc.r.s

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Forensic Sciences research 2022年第4期7卷 782-789页

作者： Alaric c.W.Koh Kai Yuan Yeoh Forensic chemistry and Physics Laboratory Health Sciences AuthoritySingapore

Toolmarks,particularly those found on bulky,inaccessible or immovable items,can be recovered by *** allow for subsequent comparative examinations,the casting material,typically polysiloxanes or silicones,must be able to capture and preserve fine details within a toolmark *** study the stability of such details after exposure to heat,toolmark casts were heated at either 60°c for 2 h,or 90°c for 1 *** casts were subsequently compared to casts that had not been exposed to heat,using traditional optical comparison microscopy,as well as virtual comparison *** toolmark signatures were also extracted from the casts and compared pairwise to obtain quantitative similarity sc.r.s based on cross-c.r.elation,consecutive matching striae and Mann-Whitney *** results show that the fine surface details captured on all four commercial toolmark casting materials tested herein remained stable after exposure to *** study shows that the above heating protocols are viable viral inactivation methods for toolmark casts that are potentially contaminated with human c.r.naviruses,such as *** findings also apply to other scenarios,such as for casts that were left in a vehicle parked under the sun.

关键词： Forensic sciences casts c.r.navirus comparison microscopy polysiloxane thermal stability toolmarks

Effect of nitrogen fertilizer on biomass production and nodulation behavior of Pongamia pinnata Pierre seedlings under nursery conditions

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Journal of Forestry research 2013年第3期24卷 531-538页

作者： S.P. chaukiyal rayees Afzal Mir T.c. Pokhriyal Plant Physiology Botany Division. Forest Research InstituteDehradun Uttarakhand India

At the seedling stage, a small amount of N is required to boost growth of leguminous plants. A pot experiment was conducted to observe the effect of N fertilizer on various growth parameters and nodulation behavior of Pongamia pinnata under nursery conditions. After the estab- lishment of seedlings, four nitrogen treatments, 0, 40, 80 and 100 kg-ha^-1 N were applied in two equal splits. Monthly observations were taken for the morphological parameters viz. plant height, collar diameter, leaf number, root length, root shoot ratio, nodule number and weight per plant. Maximum plant height was rec.r.ed after application of N at 40 ***^-1. Seasonally, the difference in collar diameter in rainy season was signifi- cantly higher than in winter or summer. However, more leaves were produced per plant at N-40 and N-100 treatments in winter and rainy seasons. Higher root length was rec.r.ed in rainy season than in winter or summer. root biomass was higher than for stems or leaves. Seasonal effects of N-80 and N-40 treatments on leaf dry weight were significantly higher than for N-100 or N-0. Stem dry weight was higher at N-40 than at other treatments in winter and summer seasons. root：shoot ratio was higher throughout winter to early summer. Nodule biomass was 2-3 times higher in rainy season compared to winter or summer. Maximum nodule number and biomass per plant were highest at N-40, followed by N-0, N-80 and N-100 treatments. New nodule formation started from June to the end of September. Maximum biomass per plant was rec.r.ed at N-40, followed by N-80, N-100 and N-0. Nitrogen treatment effect and seasonal behaviour interaction were not significant. Significantly higher numbers of nodules per plant were rec.r.ed in rainy season followed by summer and winter for all treatments. Higher nitrogen doses suppressed growth while lower doses promoted growth in Pongamia pinnata. Therefore, the lower nitrogen dose i.e., N-40 ***^-1 applied in two equal splits was suitable at the

关键词： Pongamia pinnata biomass nitrogen treatments seasonalbehaviour

Open land-use map:a regional land-use mapping strategy for inc.r.orating OpenStreetMap with earth observations

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Geo-Spatial Information Science 2017年第3期20卷 269-281页

作者： Di Yang chiung-Shiuan Fu Audrey c.Smith Qiang Yu Department of Geography University of FloridaGainesvilleFLUSA Land Use and Environmental change Institute University of FloridaGainesvilleFLUSA Beijing Key Laboratory of Precision Forestry Beijing Forestry UniversityBeijingChina

A land-use map at the regional scale is a heavy computation task yet is critical to most landowners,researchers,and decision-makers,enabling them to make informed decisions for varying *** are two major difficulties in generating land classification maps at the regional scale:the necessity of large data-sets of training points and the expensive computation cost in terms of both money and *** Geographic Information opens a new era in mapping and visualizing the physical world by providing an open-access database valuable georeferenced information collected by volunteer *** one of the most well-known VGI initiatives,OpenStreetMap(OSM),contributes not only to road network distribution information but also to the potential for using these data to justify and delineate land ***,most large-scale mapping approaches-including regional and national scales–confuse“land cover”and“land-use”,or build up the land-use database based on modeled land cover data-sets,in this study,we clearly distinguished and differentiated land-use from land *** focusing on our prime objective of mapping land-use and management practices,a robust regional land-use mapping approach was developed by integrating OSM data with the earth observation remote sensing *** novel approach inc.r.orates a vital temporal component to large-scale land-use mapping while effectively eliminating the typically burdensome computation and time/money demands of such ***,our novel approach in regional scale land-use mapping produced robust results in our study area:the overall internal acc.r.cy of the classifier was 95.2%and the external acc.r.cy of the classifier was measured at 74.8%.

关键词： OpenStreetMap(OSM) Volunteered Geographic Information(VGI) crowdsourced data random Forest Google Earth Engine(GEE)