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Tropical ash(Fraxinus udhei)invading Andean forest remnants in Northern South America

Ecological Processes 2018年第1期7卷 152-164页

作者： Kelly A.Saavedra-ramírez AndrésEtter Alberto ramírez Depa rtamento de Ecologia y Territoto Pontificia Universidad averianaBogotaColomba

Introduction:Exotic invasive species represent a major driver of the loss of biological diversity and services provided by ecosystems *** important cause of species becoming invasive is the development of commercial afforestation projects using fast-growing and adaptable exotic species,which may become invasive impacting natural *** tropical ash(Fraxinus uhdei),native to México,has been widely introduced to Colombia and other countries for timber,live fences,and urban *** is now common in many areas of the tropical mountains and has been observed expanding into native forests in *** study examined the invasion pattern and the demographic structure of tropical ash in remnant Andean forests in Colombia,to find out factors associated with the invasion *** analysis took into account biotic and physical factors:distance to propagule source,vegetation cover types,and understory and canopy ***:Although the reproductive strategy of the tropical ash is of“r”type with low survival rates,the results show evidence for an active process of invasion characterized by an aggregated distribution pattern dominated by seedlings and juvenile *** study shows the existence of an interaction between the distance to propagule source and the vegetation cover,which has an additive effect on the demographic structure of the ***:This study suggests an active invasion process by the exotic tree tropical ash into a remnant of sub-humid forests in the Andean *** results showed an expanding population process with a decreasing average age from propagule sources and mature reproductive individuals within the native forest,which bring new individuals that are colonizing new areas and advancing into the *** research points to the need for urgent plant intervention on two aspects:the use of the tropical ash and the management of the invasion process in native forests.

关键词： Andean forest Demographic structure Fraxinus uhdei Exotic species Plant biological invasions Invasion pattern

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An Evolutionary Approach to Improve the Beam Steering Performance over Conventional Approach in CHAA

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Journal of Communications and Information Networks 2023年第2期8卷 164-170页

作者： K Akhitha Gopi ram National Institute of Technology Warangal 506004India

In this work,evolutionary algorithms are applied for the first time to achieve better radiation characteristics over the conventional beamforming algorithm in the concentric hexagonal antenna array(CHAA),which improves the performance of wireless *** signal classification(MUSIC)algorithm is employed for direction of arrival(DoA)*** conventional adaptive beam steering algorithm,least mean-square(LMS)algorithm,is used to steer the ***,the proposed approach is employed by novel particle swarm optimization(NPSO)to reduce sidelobe level(SLL)even further.A six-ring CHAA with 126 elements for DoA estimation and beam steering is *** simulation results of the MUSIC,LMS,NPSO,and particle swarm optimization(PSO)algorithms are provided for various DoAs.

关键词： smart antenna hexagonal array PSO MUSIC algorithm LMS algorithm DoA estimation beam steering NPSO

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THE SUFFICIENT EFFICIENCY CONDITIONS IN SEMIINFINITE MULTIOBJECTIVE FRACTIONAL PROGramMING UNDER HIGHER ORDER EXPONENTIAL TYPE HYBRID TYPE INVEXITIES

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Acta Mathematica Scientia 2015年第6期35卷 1437-1453页

作者： ram U.VERMA Department of Mathematics Texas State University

First, a class of higher order exponential type hybrid （α,β, γ, η, p, h（.,.）, κ（., .）, w（.,., .）, ω（.,.,.）, θ）-invexities is introduced, second, some parametrically sufficient efficiency conditions based on the higher order exponential type hybrid invexities are established, and finally some parametrically sufficient efficiency results under the higher order exponential type hybrid （a,β, γ, ρ, h（.,.）, k（.,-）, w（-,., .）, w（.,., .）, 0）-invexities are investigated to the context of solving semiinfinite multiobjective fractional programming problems. The notions of the higher order exponential type hybrid （a, β, γ η, p, h（., .）, n（., .）, w（-,.,-）, ω（.,.,.）, 0）-invexities encompass most of the generalized invexities in the literature. To the best of our knowledge, the results on semiinfinite multiobjective fractional programming problems established in this communication are new and application-oriented toward multitime multi- objectve problems as well as multiobiective control problems.

关键词： semiinfinite fractional programming multiobjective fractional programming,Hanson-Antczak-type generalized HAα,β,γ,η,ρh-V-invex functions hy-(α,β,γ,η,ρh(.,.),k(.,.),w(.,.,.)w(.,.,.),θ-invexity)

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ELLIPTIC RECONSTRUCTION AND A POSTERIORI ERROR ESTIMATES FOR FULLY DISCRETE SEMILINEAR PARABOLIC OPTIMAL CONTROL PROBLEMS

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Journal of Computational Mathematics 2022年第2期40卷 147-176页

作者： ram Manohar Rajen Kumar Sinha Department of Mathematics Indian Institute of Technology GuwahatiGuwahati-781039India

This article studies a posteriori error analysis of fully discrete finite element approximations for semilinear parabolic optimal control *** on elliptic reconstruction approach introduced earlier by Makridakis and Nochetto[25],a residual based a posteriori error estimators for the state,co-state and control variables are *** space discretization of the state and co-state variables is done by using the piecewise linear and continuous finite elements,whereas the piecewise constant functions are employed for the control *** temporal discretization is based on the backward Euler *** derive a posteriori error estimates for the state,co-state and control variables in the L^(∞)(0,T;L^(2)(Ω))-***,a numerical experiment is performed to illustrate the performance of the derived estimators.

关键词： Semilinear parabolic optimal control problem Finite element method The backward Euler method Elliptic reconstruction A posteriori error estimates

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Effect of Rare Earth and Transition Metal Elements on the Glass Forming Ability of Mechanical Alloyed Al–TM–RE Based Amorphous Alloys

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Journal of Materials Science & Technology 2015年第11期31卷 1118-1124页

作者： ram S.Maurya Tapas Laha Department of Metallurgical & Materials Engineering Indian Institute of Technology Kharagpur

The present work aims to compare the amorphous phase forming ability of ternary and quaternary Al based alloys （Al86Ni8Y6, Al86GNi6Y6Co2, Al86NigLa6 and Al86Ni8Y45La15） synthesized via mechanical alloying by varying the composition, i.e. fully or partially replacing rare earth （RE） and transition metal （TM） elements based on similar atomic radii and coordination number. X-ray diffraction and high resolution transmission electron microscopy study revealed that the amorphization process occurred through formation of various intermetallic phases and nanocrystalline FCC Al. Fully amorphous phase was obtained for the alloys not containing lanthanum, whereas the other alloys containing La showed partial amorphization with reappearance of intermetallic phases attributed to mechanical crystallization. Differential scanning calorimetry study confirmed better thermal stability with wider transformation temperature for the alloys without La.

关键词： Al-TM-RE amorphous alloy Mechanical alloying Glass forming ability Microstructural transformation Intermetallics Glass transition temperature

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Single Molecule Analysis of the Arabidopsis FRA1 Kinesin Shows that It Is a Functional Motor Protein with Unusually High Processivity

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Molecular Plant 2011年第5期4卷 879-885页

作者： Chuanmei Zhu ram Dixit Biology Department Washington University St Louis MO 63130 USA

The Arabidopsis FRA1 kinesin contributes to the organization of cellulose microfibrils through an unknown mechanism. The cortical localization of this kinesin during interphase raises the possibility that it transports cell wallrelated cargoes along cortical microtubules that either directly or indirectly influence cellulose microfibril patterning. To determine whether FRA1 is an authentic motor protein, we combined bulk biochemical assays and single molecule fluorescence imaging to analyze the motor properties of recombinant, GFP-tagged FRA1 containing the motor and coiled-coil domains （designated as FRAI（707）-GFP）. We found that FRAI（707）-GFP binds to microtubules in an ATP-dependent manner and that its ATPase activity is dramatically stimulated by the presence of microtubules. Using single molecule studies, we found that FRAI（707）-GFP moves processively along microtubule tracks at a velocity of about 0.4 μm s-1. In addition, we found that FRAI（707）-GFP is a microtubule plus-end-directed motor and that it moves along microtubules as a dimer. Interestingly, our single molecule analysis shows that the processivity of FRAI（707）-GFP is at least twice the processivity of conventional kinesin, making FRA1 the most processive kinesin to date. Together, our data show that FRA1 is a bona fide motor protein that has the potential to drive Iong-distance transport of cargo along cortical microtubules.

关键词： Kinesin FRA1 cortical microtubule single molecule cellulose Arabidopsis.

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Endoscopic ultrasound-guided gastroenterostomy for gastric outlet obstruction in Mexico

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World Journal of Surgical Procedures 2024年第3期14卷 15-20页

作者： Massiel Madelin Rosario-Morel Rodrigo Soto-Solis Katia Picazo-Ferrera Miriam Idalia Torres-Ruiz JoséAlberto Estradas-Trujillo Mario Alberto Gallardo-ramírez Gerardo Akram Darwich-del Moral Luis Ariel Waller-González Department of Endoscopy Centro Médico Nacional“20 de Noviembre”ISSSTEMexico City 03229Mexico Department of Gastroenterology HospitalÁngeles PedregalMexico City 10700Mexico Department of Endoscopy Centro Médico ABCMexico City 01120Mexico Department of Endoscopy Hospital General de México“Dr.Eduardo Liceaga”Mexico City 06720Mexico

BACKGROUND Endoscopic ultrasound-guided gastroenterostomy(EUS-GE)has recently emerged as an alternative treatment for gastric outlet obstruction(GOO)in selected *** To report the initial experience of EUS-GE in patients with *** This study was a retrospective,observational,multicenter study in which the data from 10 patients who underwent EUS-GE due to GOO between September 2021 and May 2023 were *** analyzed technical success,clinical success,adverse events,and *** success was defined as adequate positioning and deployment of the *** success was defined as the patient’s ability to tolerate oral intake without vomiting 7 d after the *** adverse events were *** Eleven procedures in 10 patients with GOO were *** mean age of the patients was 67.5 years(range:56-77 years).Malignant GOO was present in 9 *** success was achieved in 9/11 procedures(82%).Among them,clinical success was achieved in 9 patients(100%).Adverse events occurred in 1 patient(9%).The median survival was 3 months(n=7;range:1-8 months).CONCLUSION EUS-GE is a feasible therapeutic option in the treatment of GOO.

关键词： Endoscopic ultrasound-guided gastroenterostomy Gastric outlet obstruction Lumen apposing metal stent Interventional endoscopic ultrasound Gastrojejunostomy Duodenal stenting

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State of the art review on physiochemical and engineering characteristics of fly ash and its applications

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International Journal of Coal Science & Technology 2022年第1期9卷 21-45页

作者： Amit Kumar ram Supriya Mohanty Department of Civil Engineering Indian Institute of Technology(Banaras Hindu University)Varanasi 221005India

The focus of this study is to critically review the physiochemical and engineering properties of the fly ash and its applications in various *** utilization of fly ash has become a widespread area,but the amount of utilization is still a serious *** has many beneficial qualities(such as pozzolanic property,fineness,spherical shape,lightweight,etc.),which enhance its properties and make it suitable for its utilization as a new construction *** the bulk utilization of fly ash,it should be employed in the areas independent of any other *** that,the disposal problem can be reduced *** knowledge of its physiochemical characteristic helps in the judgment of appropriate fly ash for any particular type of *** ash can be utilized in other areas such as asphalt concrete,geopolymer concrete,ground improvement,agricultural sector,roller compacted concrete,brick,*** will reduce the existing ashes,and also the disposal problem can be solved *** implementation of fly ash must be avoided below the natural ground water level and below 4°C temperature conditions.

关键词： Fly ash Chemical property Engineering property Construction material

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Electron Paramagnetic Resonance and Optical Absorption of VO2+Doped Ammonium Selenate Single Crystals

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Chinese Physics Letters 2011年第3期28卷 203-206页

作者： ram Kripal Ashutosh Kumar Shukla Department of Physics University of AllahabadAllahabad 211002India Department of Physics Ewing Christian CollegeAllahabad 211003India

An electron paramagnetic resonance study of vanadyl ions doped in ammonium selenate single crystals is carried out at room *** is found that the VO^(2+)ion takes up an interstitial *** spin Hamiltonian parameters obtained from the crystal rotations are g‖=1.9576±0.0002,g⊥=1.9889±0.0002,A‖=203±2 G,A⊥=78±2 *** optical absorption study is also carried out to evaluate various bonding *** the basis of these parameters the nature of bonding in the complex is discussed.

关键词： temperature parameters bonding

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A prototype for on-site generation of chlorinated disinfectant for use in rural aqueducts

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Water Science and Engineering 2024年第1期17卷 33-40页

作者： Diana Marcela Cuesta Parra Felipe Correa Mahecha Andrés Felipe Rubio Pinzon Davidcamilo ramirez Bustos Leonel Alveyro Teran Llorente Miguel Fernando Jimenez Jimenez Chemical and Environmental Engineering Department Fundacion Universidad de AmericaBogota 117111Colombia Chemical Engineering Department Fundacion Universidad de AmericaBogota 117111Colombia Mecanical Engineering Department Fundacion Universidad de AmericaBogota 117111Colombia

Sodium hypochlorite has significant potential as a sanitation solution in hard-to-reach *** studies have investigated the optimal electrolysis parameters for its production with volumes greater than 1o *** study evaluated sodium hypochlorite production through electrolysis in a 22-L prototype and identified the optimal operating *** were performed using graphite electrodes with areas of 68.4 cm^(2) at the laboratory scale and 1865.0 cm^(2) at the prototype scale.A design for experiments with different operating times,chloride concentrations,and electric current intensities was *** optimal operating time,sodium chloride concentration,and current intensity at the laboratory scale were 120 min,150 g of chloride per liter,and 3 A,respectively,leading to the production of 5.02 g/L of the disinfectant with an energy efficiency of 12.21 mg of Cl_(2) per *** the prototype scale,the maximum sodium hypochlorite concentration of 3.99 g of chloride per liter was achieved with an operating time of 120 min,a sodium chloride concentration of 100 g of chloride per liter,and a current intensity of 70 A,reaching an energy efficiency of 42.56 mg of Cl_(2) per *** addition,this study evaluated the influences of the chloride concentration,current intensity,and operating time on the production of sodium hypochlorite at the two scales,and formulated the equations showing the trends of sodium hypochlorite production and energy efficiency in the electrochemical *** 22-L prototype model for production of this oxidizing substance is promising for disinfection of large volumes of water in areas that are difficult to access.

关键词： Disinfection Electrolysis Energy efficiency Optimization Sodium hypochlorite

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