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Selection and quality assessment of landsat data for the North American forest dynamics forest history maps of the US

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International Journal of Digital Earth 2016年第10期9卷 963-980页

作者： Karen Schleeweis Samuel N.Goward Chengquan Huang john l.dwyer Jennifer l.Dungan Mary A.lindsey Andrew Michaelis Khaldoun Rishmawi Jeffery G.Masek Forest Inventory and Analysis US Forest ServiceRocky Mountain Research StationOgdenUTUSA Department of Geographical Sciences University of MarylandCollege ParkMDUSA U.S.Geological Survey Earth Resources Observation and Science(EROS)Center Sioux FallsSDUSA NASA Ames Research Center Moffett FieldCAUSA Climate Program Office NOAAWashingtonDCUSA NASA Ames Research Center University Corporation Monterey BayMoffett FieldCAUSA NASA Goddard Space Flight Center GreenbeltMDUSA

Using the NASA Earth Exchange platform,the North American Forest Dynamics(NAFD)project mapped forest history wall-to-wall,annually for the contiguous US(1986–2010)using the Vegetation Change Tracker *** with any effort to identify real changes in remotely sensed time-series,data gaps,shifts in seasonality,misregistration,inconsistent radiometry and cloud contamination can be sources of *** discuss the NAFD image selection and processing stream(NISPS)that was designed to minimize these sources of *** NISPS image quality assessments highlighted issues with the landsat archive and metadata including inadequate georegistration,unreliability of the pre-2009 l5 cloud cover assessments algorithm,missing growing-season imagery and paucity of clear *** maps of landsat 5–7 image quantities and qualities are presented that offer novel perspectives on the growing-season archive considered for this *** 150,000+landsat images were considered for the NAFD ***,one high quality cloud-free image in each year or a total of 12,152 images would be ***,to accommodate data gaps and cloud/shadow contamination 23,338 images were *** 220 specific path-row image years no acceptable images were found resulting in data gaps in the annual national map products.

关键词： landsat forest cover change time-series mapping forest disturbance North American forest dynamics nasa earth exchange

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Optimization of specific cell-peptide interactions at the bio-material interface via regulation of nonspecific biofouling interactions

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Science China Chemistry 2020年第2期63卷 143-144页

作者： john l.Brash Department of Chemical Engineering School of Biomedical EngineeringMcMaster University

Materials that interact with biological systems in a wellcontrolled,predictable manner are highly sought after for numerous biomedical and biotechnological *** example,it is essential that devices such as stents or heart valves in the blood stream of patients do not cause thrombosis or infection,or that biosensors do not lose their function due to adverse interactions with the bio environment.A general approach to the design of biointerfaces that addresses this need has been pursued over a number of years[1].It has two elements:(1)prevention of non-specific interfacial interactions,and(2)promotion of specific biointeractions required for the intended functioning of the *** practice this means preventing all interactions except for the desired one(s).With respect to the first point it should be appreciated that biological species such as proteins and cells have a natural affinity for the interfacial ***,the realization of a surface that eliminates the adsorption/adhesion of these species is extremely *** of PEO/PEG,other hydrophilic polymers(PVP,PHEMA),and zwitterionic polymers[2]to the surface is the most common strategy to achieve“bio-resistance”.Regarding the second point,the surface must be designed so that it interacts selectively and exclusively with the component(s)(proteins,cells)that will give the desired *** this purpose,“ligands”that bind these specific components are incorporated into the surface[3].

关键词： desired interfacial realization

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Ionic conductivity anomaly in soil cover——Exploration of blind mineralization beneath regolith cover

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Science China Earth Sciences 2010年第5期53卷 649-656页

作者： KEElING john l. Primary Industries and Resources South Australia (PIRSA)

This paper briefly describes the formation of ionic conductivity anomalies in soil cover, and the characteristics of ionic composition that forms conductivity anomalies, based on the theory of geoelectrochemical halo. Based on some practical results of soluble ions in soil cover and soil conductivity derived from a number of mining areas of both China and overseas, here we present the correlation of a conductivity anomaly with the ionic composition and establish a model for the formation of conductivity anomalies in soil cover. The results indicate that the formation of a conductivity anomaly is not a simple transformation of a secondary geochemical anomaly. A conductivity anomaly is formed as the result of electrochemical and chemical processes, by transformation of orebody into various ionic haloes through four physicochemical processes: 1) dissolution of the orebody, 2) migration of dissolved matter, 3) conversion of matter near the surface, and 4) the formation of ionic conductivity anomalies. The conductivity anomaly, as a physical parameter, essentially represents the integration of various geochemical compositions and is controlled by a set of particular ionic groups.

关键词： ionic conductivity regolith mineralisation exploration

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Synthesis of liSm_(0.01)Mn_(1.99)O_4 by molten salt technique

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Journal of Rare Earths 2010年第2期28卷 255-259页

作者： M Helan l john Berchmans Department of Chemistry Jamal Mohamed College (Autonomous) Electropyrometallurgy Division Central Electrochemical Research Institute

Samarium substituted lithium manganese oxide powders were successfully prepared by molten-salt synthesis(MSS) using eutectic mixture of liCl,SmCl3.6H2O and MnO2 salt at 700 °*** synthesis was carried out in open *** crystalline powders were characterized for their phase identification using X-ray diffraction(XRD) *** physico-chemical properties of the samarium substituted lithium manganese oxide powders were investigated by thermal analysis(TGA/DTA),FT-IR spectroscopy,EDAX,electron par...

关键词： liSm0.01Mn1.99O4 molten salt synthesis cathode materials rare earth ion

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Mechanisms, prevention and clinical implications of nonsteroidal anti-inflammatory drug-enteropathy

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World Journal of Gastroenterology 2013年第12期19卷 1861-1876页

作者： john l Wallace Farncombe Family Digestive Health Research Institute McMaster University Inflammation Research Network University of Calgary

This article reviews the latest developments in understanding the pathogenesis, detection and treatment of small intestinal damage and bleeding caused by nonsteroidal anti-inflammatory drugs (NSAIDs). With improvements in the detection of NSAID-induced damage in the small intestine, it is now clear that this injury and the associated bleeding occurs more frequently than that occurring in the stomach and duodenum, and can also be regarded as more dangerous. However, there are no proven-effective therapies for NSAID-enteropathy, and detection remains a challenge, particularly because of the poor correlation between tissue injury and symptoms. Moreover, recent studies suggest that commonly used drugs for protecting the upper gastrointestinal tract (i.e., proton pump inhibitors) can significantly worsen NSAID-induced damage in the small intestine. The pathogenesis of NSAID-enteropathy is complex, but studies in animal models are shedding light on the key factors that contribute to ulceration and bleeding, and are providing clues to the development of effective therapies and prevention strategies. Novel NSAIDs that do not cause small intestinal damage in animal models offer hope for a solution to this serious adverse effect of one of the most widely used classes of drugs.

关键词： Anti-inflammatory Ulcer Prostaglandin Non-steroidal Bleeding Intestinal Bile Enterohepatic Bacteria Hydrogen sulfide Aspirin Hemorrhage

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Diverse outcomes of species interactions in an invaded annual plant community

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Journal of Plant Ecology 2017年第6期10卷 918-926页

作者： Claire E.Wainwright john M.dwyer Richard J.Hobbs Margaret M.Mayfield The Ecology Centre School of Biological SciencesBuilding 8The University of QueenslandSt LuciaQueensland 4072Australia Commonwealth Scientific and Industrial Research Organisation Land and WaterEcoSciences PrecinctDutton ParkQueensland 4001Australia School of Plant Biology The University of Western Australia35 Stirling HighwayCrawleyWestern Australia 6009Australia

Aims Despite acknowledgement that interactions among native and exotic species are important for determining the structure and diversity of novel communities,directed experiments using mul-tiple exotics from the same system are *** observational studies have highlighted distinct ways that exotic species interface with resident natives across invaded *** correlative nature of these studies,however,has provided few details about the mechanisms driving distinct interaction outcomes within the same *** aim was to determine how three exotic annual plant species with distinct relationships with local plant diversity impact the performance of a co-occurring native annual in the York gum-jam woodlands of Western *** We grew species in experimental communities in growth chambers at varying total planting densities to assess how interaction out-comes varied among natives and exotics across a gradient of com-petition *** measured a variety of performance responses,including survival,biomass and population-level and individual-level reproductive *** Findings Overall,the effects of interspecific versus intraspecific competi-tion on performance varied with the identity and density of exotic *** exploitative exotic grass Bromus madritensis was dominant in polyculture,whereas the diminutive grass Pentameris airoides conferred weak intraspecific competition and interspe-cific facilitation on native Waitzia *** exotic broadleaf forb,Hypochaeris glabra,suppressed growth and survival of ***,while *** had weakly negative,neutral or positive effects on all *** outcomes highlight the complexity of interac-tions impacting the diversity,stability and structure of novel plant *** few of these communities contain a single exotic species,understanding the competitive dynamics occurring in diverse novel communities is critical for their conservation and restoration.

关键词： annual plants biotic interactions competition invasion novel ecosystems

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Configuration-Sensitive Molecular Sensing on Doped Graphene Sheets

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Nano Research 2010年第7期3卷 472-480页

作者： john Russell Petr Král Department of Chemistry University of Illinois at ChicagoChicagoIL 60607USA

We show by molecular dynamics simulations that configuration-sensitive molecular spectroscopy can be realized on optimally doped graphene sheets vibrated by an oscillatory electric *** selectivity of the spectroscopy is achieved by maximizing Coulombic binding between the detected molecule and a specific nest,formed for this molecule on the graphene sheet by substituting selected carbon atoms with boron and nitrogen *** can detect binding of different isomers to the nest from the frequency shifts of selected vibrational modes of the combined *** an illustrative example,we simulate detection of hexanitrostilbene enantiomers in chiral nests formed on graphene.

关键词： Molecular sensing enantiomer graphene functionalization molecular dynamics

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Integration of the Coupled Orbit-Attitude Dynamics Using Modified Chebyshev-Picard Iteration Methods

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Computer Modeling in Engineering & Sciences 2016年第2期111卷 129-146页

作者： Xiaoli Bai john l.Junkins Rutgers The State University of New JerseyPiscatawayNJU.S.A Texas A&M College StationTXU.S.A

This paper presents Modified Chebyshev-Picard Iteration(MCPI)methods for long-term integration of the coupled orbit and attitude *** most orbit predictions for operational satellites have assumed that the attitude dynamics is decoupled from the orbit dynamics,the fully coupled dynamics is required for the solutions of uncontrolled space debris and space objects with high area-to-mass ratio,for which cross sectional area is constantly changing leading to significant change on the solar radiation pressure and atmospheric *** is a set of methods for solution of initial value problems and boundary value *** methods refine an orthogonal function approximation of long-time-interval segments of state trajectories iteratively by fusing Chebyshev polynomials with the classical Picard iteration and have been applied to multiple challenging aerospace *** the studies on integrating a torque-free rigid body rotation and a long-term integration of the coupled orbit-attitude dynamics through the effect of solar radiation pressure,MCPI methods are shown to achieve several times speedup over the Runge-Kutta 7(8)methods with several orders of magnitudes of better *** methods are further optimized by integrating the decoupled dynamics at the beginning of the iteration and coupling the full dynamics when the attitude solutions and orbit solutions are converging during the *** approach of decoupling and then coupling during iterations provides a unique and promising perspective on the way to warm start the solution process for the longterm integration of the coupled orbit-attitude ***,an attractive feature of MCPI in maintaining the unity constraint for the integration of quaternions within machine accuracy is illustrated to be very appealing.

关键词： Orbit propagation orbit-attitude dynamics Modified Chebyshev-Picard Iteration(MCPI)Methods

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ANAlYSIS OF COMPOSITE lAMINATE BEAMS USING COUPlING CROSS-SECTION FINITE ElEMENT METHOD

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Applied Mathematics and Mechanics(English Edition) 2006年第12期27卷 1709-1718页

作者：姜文光 john l.Henshall School of Mechanical Engineering Yanshan UniversityQinhuangdao 066004Hebei ProvinceP. R. China Department of Aerospace Engineering University of BristolBS8 1TRUK Department of Mechanical Engineering and Manufacturing Engineering Nottingham Trent UniversityNottinghamNG1 4BUUK

Beams and plates manufactured from laminates of composite materials have distinct advantages in a significant number of applications. However, the anisotropy arising from these materials adds a significant degree of complexity, and thus time, to the stress and deformation analyses of such components, even using numerical approaches such as finite elements. The analysis of composite laminate beams subjected to uniform extension, bending, and/or twisting loads was performed by a novel implementation of the usual finite element method. Due to the symmetric features of the deformations, only a thin slice of the beam to be analysed needs to be modelled. Conventional threedimensional solid finite elements were used for the structural discretization. The accurate deformation relationships were formulated and implemented through the coupling of nodal translational degrees of freedom in the numerical analysis. A sample solution for a rectangular composite laminate beam is presented to show the validity and accuracy of the proposed method.

关键词： composite material beam coupling equation finite element method extension bending torsion

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Recent trends in the surgical management of inflammatory bowel disease

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World Journal of Gastroenterology 2008年第3期14卷 408-412页

作者： Robert E Roses john l Rombeau University of Pennsylvania School of Medicine Philadelphia Pennsylvania Temple University School of Medicine Philadelphia Pennsylvania United States

Surgery is required in the vast majority of patients with Crohn’s disease (CD) and in approximately one-third of patients with ulcerative colitis (UC). Similar to medical treatments for IBD, significant advances have occurred in surgery. Advances in CD include an emphasis upon conservatism as exemplified by more limited resections, strictureplasties, and laparoscopic resections. The use of probiotics in selected patients has improved the outcome in patients with pouchitis following restorative proctocolectomy for UC. It is anticipated that ongoing discoveries in the molecular basis of IBD will in turn identify those patients who will best respond to surgery.

关键词： Crohn's disease Ulcerative colitis Ileal pouchanal anastomosis laparoscopic colectomy

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