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Aphidophagous guilds on nettle （Urtica dioica） strips close to fields of green pea, rape and wheat

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Insect Science 2007年第5期14卷 419-424页

作者： AMMAR ALHMEDI eric HAUBRUGE BERNARD BODSON FREDeric FRANCIS Functional and Evolutionary Entomology Experimental Farm Gembloux Agricultural University Gembloux Belgium

The common nettle （Urtica dioica L.） is a perennial and cosmopolitan plant species and is known to be the source of food for a great diversity of insects. To understand the importance of the nettle in agro-ecosystems, a field experiment was carried out in an experimental farm at Gembloux （Belgium） to study the effect of nettle margin strips on aphid and aphidophagous populations in close field crops, namely wheat （Triticum aestivum L.）, green pea （Pisum sativum L.） and rape （Brassicae napus L.）. The aphids and related beneficial populations were weekly assessed, from March to August 2005, by visual observations in two plots per field crop. A higher abundance of aphidophagous beneficials was collected in nettle strips when compared to the field crops. Particularly, the presence of predatory anthocorids, mirids and green lacewings was observed on nettle only. Nevertheless, the most abundant aphid predatory family, the Coccinellidae, was distributed in both environments, in nettle strips and in crop fields. The field margin supported a significantly higher density ofHarmonia axyridis than the field crops. In contrast, the field crops, green pea particularly, supported a higher density of Coccinella septempunctata. The distribution of the aphidophagous species, mainly the ladybirds, was discussed in relation to the host plant and related aphid species and their potential effect on integrated pest management.

关键词： Aphidophagous ladybirds beneficials insect diversity nettle wheat greenpea rape margin strips integrated pest management Microlophium camosum Acyrthosiphonpisum Sitobion avenae

Re-engineering artificial muscle with microhydraulics

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Microsystems & Nanoengineering 2017年第1期3卷 278-285页

作者： Jakub Kedzierski eric Holihan Rafmag Cabrera Isaac Weaver Massachusetts Institute of Technology Lincoln Laboratory LexingtonMA 02420USA

We introduce a new type of actuator,the microhydraulic stepping actuator(MSA),which borrows design and operational concepts from biological muscle and stepper *** offer a unique combination of power,efficiency,and scalability not easily achievable on the *** actuator works by integrating surface tension forces produced by electrowetting acting on scaled droplets along the length of a thin *** muscle,MSAs have liquid and solid functional components and can displace a large fraction of their *** 100μm pitch MSA presented here already has an output power density of over 200 W kg^(−1),rivaling the most powerful biological muscles,due to the scaling of surface tension forces,MSA’s power density grows quadratically as its dimensions are reduced.

关键词： artificial muscle electrowetting linear actuator microactuator microsystem microhydraulic stepping actuator

A Uniformly Robust Staggered DG Method for the Unsteady Darcy-Forchheimer-Brinkman Problem

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Communications on Applied Mathematics and Computation 2022年第1期4卷 205-226页

作者： Lina Zhao Ming Fai Lam eric Chung Department of Mathematics The Chinese University of Hong KongHong Kong SARChina

In this paper,we propose and analyze a uniformly robust staggered DG method for the unsteady Darcy-Forchheimer-Brinkman *** formulation is based on velocity gradient-velocity-pressure and the resulting scheme can be flexibly applied to fairly general polygonal *** relax the tangential continuity for velocity,which is the key ingredi-ent in achieving the uniform *** present well-posedness and error analysis for both the semi-discrete scheme and the fully discrete scheme,and the theories indicate that the error estimates for velocity are independent of *** numerical experiments are presented to confirm the theoretical findings.

关键词： Staggered DG method Brinkman-Forchheimer General meshes Uniformly stable

The impact of hypoxic-ischemic brain injury on stem cell mobilization,migration,adhesion,and proliferation

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Neural Regeneration Research 2018年第7期13卷 1125-1135页

作者： Stephanie M.Parry eric S.Peeples Department of Pediatrics University of Nebraska Medical Center

Neonatal hypoxic-ischemic encephalopathy continues to be a significant cause of death or neurodevelopmental delays despite standard use of therapeutic *** use of stem cell transplantation has recently emerged as a promising supplemental therapy to further improve the outcomes of infants with hypoxic-ischemic *** the injury,the brain releases several chemical mediators,many of which communicate directly with stem cells to encourage mobilization,migration,cell adhesion and *** manuscript reviews the biomarkers that are released from the injured brain and their interactions with stem cells,providing insight regarding how their upregulation could improve stem cell therapy by maximizing cell delivery to the injured tissue.

关键词： brain-derived neurotrophic hypoxia inducible erythropoietin factor matrix metalloproteinase neonatal stromal cell-derived vascular endothelial growth

A classical equation that accounts for observations of non-Arrhenius and cryogenic grain boundary migration

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npj Computational Materials 2022年第1期8卷 1492-1500页

作者： eric R.Homer Oliver K.Johnson Darcey Britton James E.Patterson eric T.Sevy Gregory B.Thompson Department of Mechanical Engineering Brigham Young UniversityProvoUT84602USA Department of Chemistry and Biochemistry Brigham Young UniversityProvoUT84602USA Department of Metallurgical and Materials Engineering University of AlabamaTuscaloosaAL35401USA

Observations of microstructural coarsening at cryogenic temperatures,as well as numerous simulations of grain boundary motion that show faster migration at low temperature than at high temperature,have been troubling because they do not follow the expected Arrhenius *** work demonstrates that classical equations,that are not simplified,account for all these oddities and demonstrate that non-Arrhenius behavior can emerge from thermally activated *** to this classical model,this occurs when the intrinsic barrier energies of the processes become small,allowing activation at cryogenic *** thermal energy then allows the low energy process to proceed in reverse,so increasing temperature only serves to frustrate the forward *** classical form is shown to reconcile and describe a variety of diverse grain boundary migration observations.

关键词： cryogenic grain boundary

An ensemble method for gene discovery based on DNA microarray data

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Science china(Life Sciences) 2004年第5期47卷 396-405页

作者： Kathy L. MOSER eric J. TOPOL Department of Medicine Institute of Human Genetics University of Minnesota Minnesota 55455 USA Center for Cardiovascular Genetics Department of Cardiovascular Medicine the Cleveland Clinic Foundation 9500 Euclid Avenue Cleveland Ohio 44195 USADepartment of Molecular Cardiology the Cleveland Clinic Foundation 9500 Euclid Avenue Cleveland Ohio 44195 USA

The advent of DNA microarray technology has offered the promise of casting new insights onto deciphering secrets of life by monitoring activities of thousands of genes simulta-neously. Current analyses of microarray data focus on precise classification of biological types, for example, tumor versus normal tissues. A further scientific challenging task is to extract dis-ease-relevant genes from the bewildering amounts of raw data, which is one of the most critical themes in the post-genomic era, but it is generally ignored due to lack of an efficient approach. In this paper, we present a novel ensemble method for gene extraction that can be tailored to fulfill multiple biological tasks including (i) precise classification of biological types; (ii) disease gene mining; and (iii) target-driven gene networking. We also give a numerical application for (i) and (ii) using a public microarrary data set and set aside a separate paper to address (iii).

关键词： microarrays,ensemble decision,recursive partition tree,feature gene selection.

Diagnosing Ocean Tracer Transport from Sellafield and Dounreay by Equivalent Diffusion and Age

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advances in Atmospheric Sciences 2008年第5期25卷 805-814页

作者： Steinar ORRE Yongqi GAO Helge DRANGE eric DELEERSNIJDER Nansen Environmental and Remote Sensing Center Bergen Norway Bjerknes Centre for Climate Research Bergen Norway Nansen-Zhu International Research Centre Institute of Atmospheric Physics （ IAP） Chinese Academy of Sciences （ CAS） Beijing 100029 Geophysical Institute University of Bergen Bergen Norway Centre for Systems Engineering and Applied Mechanics （CESAME） Louvain School of Engineering Universite catholique de Louvain Louvain-la-Neuve Belgium

A simple approach for estimating the equivalent diffusion for diagnosing tracer transport is proposed. Two different expressions are derived; one is based directly on an analytical solution of the two-dimensional advection-diffusion equation, the other uses the variance of the tracer distribution. To illustrate some features of the equivalent diffusion and possible applications thereof, idealized releases of passive tracers from the nuclear fuel reprocessing plants at Sellafield in the Irish Sea and Dounreay on the northern coast of Scotland have been simulated with a regional isopycnic co-ordinate Ocean General Circulation Model. Both continuous and pulse releases are considered; the former being representative of the actual historical discharges from the reprocessing plants, the latter resembling an accidental scenario. Age tracers are included to calculate the mean time elapsed since the tracers left their source regions. It is found that in the Nordic Seas the age of tracers from Dounreay is approximately 2 years younger than the age from Sellafield. Although tracers from both sources eventually end up along the same transport routes, significant qualitative differences regarding the dispersion properties are found. It is argued that one single parameter, the equivalent horizontal diffusion, which is estimated to be in the range of 20 56 m^2 s^-1 from Sellafield and 170-485 m^2 s^-1 from Dounreay, determines these differences.

关键词： equivalent diffusion passive tracers age tracers sellafield dounreay

Ultralow lattice thermal conductivity of chalcogenide perovskite CaZrSe_(3) contributes to high thermoelectric figure of merit

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npj Computational Materials 2019年第1期5卷 117-123页

作者： eric Osei-Agyemang Challen Enninful adu Ganesh Balasubramanian Department of Mechanical Engineering and Mechanics Lehigh University19 Memorial Drive WestBethlehemPA 18015USA

An emerging chalcogenide perovskite,CaZrSe_(3),holds promise for energy conversion applications given its notable optical and electrical ***,knowledge of its thermal properties is extremely important,*** potential thermoelectric applications,and has not been previously reported in *** this work,we examine and explain the lattice thermal transport mechanisms in CaZrSe_(3) using density functional theory and Boltzmann transport *** find the mean relaxation time to be extremely short corroborating an enhanced phonon-phonon scattering that annihilates phonon modes,and lowers thermal *** addition,strong anharmonicity in the perovskite crystal represented by the Grüneisen parameter predictions.

关键词： properties. perovskite phonon

Tuning periodicity of polymer-decorated carbon nanotubes

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Science china Chemistry 2012年第5期55卷 802-807页

作者： LAIRD eric D. LI Christopher Y. A. J. Drexel Nanotechnology Institute and Department of Materials Science and Engineering Drexel University Philadelphia Pennsylvania 19104 USA

Carbon nanotube (CNT) is one of the most extensively investigated nanomaterials. Patterning soft matter such as liquid crystals and polymers on CNTs could potentially enable various applications for CNTs. We have demonstrated that controlled polymer crystallization using CNTs as the 1D nucleation sites can lead to periodically functionalized CNTs. Here we show that selected crystalline block copolymers can be periodically decorated along CNTs. This facile technique opens a gateway to periodic patterning on 1-D nanomaterials.

关键词： polymer crystallization carbon nanotube block copolymers