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Phloem-Mobile AuxlIAA Transcripts Target to the root Tip and Modify root Architecture

Journal of Integrative Plant biology 2012年第10期54卷 760-772页

作者： Michitaka Notaguchi Shmuel Wolf William J.lucas Department of Plant biology College of Biological SciencesUniversity of CaliforniaDavisCA 95616USA JST ErATO Higashiyama Live-Holonics Project Nagoya UniversityFuro-choChikusa-kuNagoyaauAichi 464-8602Japan The robert H.Smith Institute of Plant Sciences and Genetics in Agriculture and the Otto Warburg Minerva Center for Agricultural biotechnology The Hebrew University of JerusalemThe Robert H.Smith Faculty of AgricultureFood and EnvironmentRehovot 76100Israel

In plants, the phloem is the component of the vascular system that delivers nutrients and transmits signals from mature leaves to developing sink tissues. recent studies have identified proteins, mrNA, and small rNA within the phloem sap of several plant species. It is now of considerable interest to elucidate the biological functions of these potential long-distance signal agents, to further our understanding of how plants coordinate their developmental programs at the whole-plant level. In this study, we developed a strategy for the functional analysis of phloem-mobile mrNA by focusing on IAA transcripts, whose mobility has previously been reported in melon （Cucumis melo cv. Hale＇s best Jumbo）. Indoleacetic acid （IAA） proteins are key transcriptional regulators of auxin signaling, and are involved in a broad range of developmental processes including root development. We used a combination of vasculature-enriched sampling and hetero-grafting techniques to identify IAA18 and IAA28 as phloemmobile transcripts in the model plant Arabidopsis thaliana. Micro-grafting experiments were used to confirm that these IAA transcripts, which are generated in vascular tissues of mature leaves, are then transported into the root system where they negatively regulate lateral root formation. based on these findings, we present a model in which auxin distribution, in combination with phloem-mobile Aux/IAA transcripts, can determine the sites of auxin action.

关键词： Arabidopsis AUX/IAA lateral root development grafting phloem-mobile transcript.

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Dry reforming of methane on doped Ni nanoparticles:Featureassisted optimizations and ranking of doping metals for direct activations of CH_(4) and CO_(2)

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Nano research 2022年第10期15卷 9670-9682页

作者： Shiru Lin Jean-baptiste Tristan Yang Wang Junwei lucas bao Department of Chemistry Boston CollegeChestnut HillMassachusetts 02467USA Department of Computer Science Boston CollegeChestnut HillMassachusetts 02467USA

As a vital energy resource and raw material for many industrial products,syngas(CO and H_(2))is of great *** reforming of methane(DrM)is an important approach to producing syngas(with a hydrogen-to-carbon-monoxide ratio of 1:1 in principle)from methane and carbon dioxide,with a lower operational cost as compared to other reforming ***,many pure metallic catalysts used in DrM face deactivation issues due to coke formation or sintering of the metal particles.A systematic search for highly efficient metallic catalysts,which reduce the reaction barriers for the rate-determining steps and resist carbon deposition,is urgently *** is a typical low-cost transition metal for activating the C–H bond in *** this work,we applied a two-step workflow to search for nickel-based bimetallic catalysts with doping metals M(M-Ni)by combining density functional theory(DFT)calculations and machine learning(ML).We focus on the two critical steps in DrM—CH_(4) and CO_(2) direct *** used DFT and slab models for the Ni(111)facet to explore the relevant reaction pathways and constructed a data set containing structural and energetic information for representative M-Ni *** used this dataset to train ML models with chemical-knowledge-based features and predicted CH_(4) and CO_(2) dissociation energies and barriers,which revealed the composition–activity relationships of the bimetallic *** also used these models to rank the predicted catalytic performance of candidate systems to demonstrate the applicability of ML for catalyst *** emphasized that ML ranking models would be more valuable than regression models in high-throughput ***,we used our trained model to screen 12 unexplored M-Ni systems and showed that the DFT-computed energies and barriers are very close to the ML-predicted values for top candidates,validating the robustness of the trained model.

关键词： Ni-based bimetallic catalysts dry reforming of methane syngas production CH_(4)and CO_(2)direct activations ranking model

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Mechanical properties of Ga_xIn_(1-x)As_yP_(1-y)/GaAs system at different temperatures and pressures

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Chinese Physics b 2015年第9期24卷 313-318页

作者： A.r.Degheidy E.b.Elkenany Department of Physics Faculty of ScienceMansoura University

The mechanical properties, such as the elastic constants C11, C12, C44, and bulk, Young＇s, and shear moduli, of a Ga x In1-x As y P1-y alloy lattice matching to a Ga As substrate are calculated for various As concentrations. The calculations are based on the pseudo-potential method within the virtual crystal approximation containing the effective disorder potential. The variations of the studied properties with pressure and temperature are investigated. A comparison between the calculated results and the available published data for binary parent compounds shows that they have good agreement,while the calculated results for the quaternary alloys at various temperature and pressure may be taken as a reference.

关键词： elastic constants temperature and pressure electronic band gaps

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SECOND-OrDEr INTErACTION OF IrrEGULAr WAVES WITH A TrUNCATED COLUMN

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Acta Mechanica Sinica 1997年第2期13卷 130-142页

作者： J.b.Huang r.EatockTaylor Department of Engineering Science University of OxfordParks RoadOxfordOX1 3PJUK

A complete semi-analytical solution is obtained for second-order diffraction of plane bichromatic waves by a fixed truncated circular *** fluid domain is divided into interior and exterior *** the exterior region,the second-order velocity potential is expressed in terms of‘locked-wave’and‘free-wave’ components,both are solved using Fourier and eigenfunction *** re- sulting‘locked wave’potential is expressed by one-dimensional Green's integrals with oscillating *** order to increase computational efficiency,the far-field part of the integrals are carried out *** in both regions are matched on the interface by the potential and its normal derivative continuity *** on the present approach,the sum-and difference-frequency potentials are efficiently evaluated and are used to generate the quadratic transfer functions which correlates the incident wave spectrum with second-order forcing spectrum on the *** sum-frequency QTFs for a TLP column are present,which are compared for some frequency pairs with those from a fully numerical *** agreement has been *** spectra for a case study TLP column,generated using the semi-analytical solution are *** given are the results for nonlinear wave field around the column.

关键词： marine hydrodynamics nonlinear wave force wave-structure interaction second-order wave diffraction

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Motion of a permeable shell in a spherical container filled with non-Newtonian fluid

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Applied Mathematics and Mechanics(English Edition) 2017年第12期38卷 1697-1708页

作者： V.MISHrA b.r.GUPTA Department of Mathematics Jaypee University of Engineering and TechnologyMadhya Pradesh 473226India

This paper presents an analytical study of creeping motion of a permeable sphere in a spherical container filled with a micro-polar fluid. The drag experienced by the permeable sphere when it passes through the center of the spherical container is studied. Stream function solutions for the flow fields are obtained in terms of modified bessel functions and Gegenbauer functions. The pressure fields, the micro-rotation components, the drag experienced by a permeable sphere, the wall correction factor, and the flow rate through the permeable surface are obtained for the frictionless impermeable spherical container and the zero shear stress at the impermeable spherical container. Variations of the drag force and the wall correction factor with respect to different fluid parameters are studied. It is observed that the drag force, the wall correction factor, and the flow rate are greater for the frictionless impermeable spherical container than the zero shear stress at the impermeable spherical container. Several cases of interest are deduced from the present analysis.

关键词： micro-polar fluid permeable sphere Darcy law stream function drag force wall correction factor spherical container

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Inhibition of NO emission by adding antioxidant mixture in Jatropha biodiesel on the performance and emission characteristics of a C.I. engine

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Frontiers in Energy 2015年第2期9卷 238-245页

作者： A. PrAbU r. b. ANAND Department of Mechanical Engineering National Institute of Technol-ogy Tiruchirappalli 620015 India

In this paper, the effect of adding an antiox- idant mixture in Jatropha biodiesel as fuel, in a single cylinder, direct injection compression ignition engine was experimentally investigated and the level of pollutants in the exhaust and performance characteristics of the engine were analyzed. Nine test fuels were prepared with three antioxidants, namely, Suecinimide （C4H5NO2）, N,N-dimethyl-p-phenylenediamine-dihydrochloride （C8H14C12N2）, and N-phenyl-p-phenylenediamine （C6H5NHC6H4NH2） added to neat biodiesel at 500 parts per million （ppm）, 1000ppm and 2000ppm and the observed experimental results were compared with those of neat biodiese! and neat diesel as base fuels. The comparison showed that NO emission was reduced drastically for the test fuels with the antioxidant addition of 2000ppm. The maximum reduction of 10% of NO emission was observed for the antioxidant mixture in neat biodiesel, with a slight increase in unburned HC, CO and smoke opacity. In addition, the obtained experimental results reveal that the addition of two antioxidants as mixture in neat biodiesel caused improved NO emission reduction for all test fuels.

关键词： NO emission antioxidants Succinimide,N,N-dimethyl-p-phenylenediamine-dihydrochloride N-phenyl-p-phenylenediamine

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Exact solutions to drift-flux multiphase flow models through Lie group symmetry analysis

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Applied Mathematics and Mechanics(English Edition) 2015年第8期36卷 1105-1112页

作者： b.bIrA T.r.SEKHAr Department of Mathematics National Institute of Science and Technology Department of Mathematics Indian Institute of Technology Kharagpur

In the present paper, Lie group symmetry method is used to obtain some exact solutions for a hyperbolic system of partial differential equations （PDEs）, which governs an isothermal no-slip drift-flux model for multiphase flow problem. Those sym- metries are used for the governing system of equations to obtain infinitesimal transforma- tions, which consequently reduces the governing system of PDEs to a system of ODEs. Further, the solutions of the system of ODEs which in turn produces some exact solutions for the PDEs are presented. Finally, the evolutionary behavior of weak discontinuity is discussed.

关键词： multiphase flow drift-flux models Lie group analysis exact solution weakdiscontinuity

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The response of temperature and hydrostatic pressure of zinc-blende Ga_xIn_(1-x)As semiconducting alloys

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Chinese Physics b 2012年第12期21卷 327-334页

作者： A.r.Degheidy E.b.Elkenany Department of Physics Faculty of ScienceMansoura University

The electronic band structure of GaxIn1-xAs alloy is calculated by using the local empirical pseudo-potential method including the effective disorder potential in the virtual crystal approximation. The compositional effect of the electronic energy band structure of this alloy is studied with composition x ranging from 0 to 1. Various physical quantities such as band gaps, bowing parameters, refractive indices, and high frequency dielectric constants of the considered alloys with different Ga concentrations are calculated. The effects of both temperature and hydrostatic pressure on the calculated quantities are studied. The obtained results are found to be in good agreement with the available experimental and published data.

关键词： temperature hydrostatic pressure to GaxIn1-xAs alloys

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MicrorNA in pancreatic ductal adenocarcinoma and its precursor lesions

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World Journal of Gastrointestinal Oncology 2016年第1期8卷 18-29页

作者： yasmin g hernandez aimee l lucas department of internal medicine icahn school of medicine at mount sinaiNew YorkNY 10029United States henry janowitz division of gastroenterology icahn school of medicine at mount sinaiNew YorkNY 10029United States

Pancreatic ductal adenocarcinoma(PDAC) is the 4^(th) deadliest cancer in the United States, due to its aggressive nature, late detection, and resistance to chemotherapy. The majority of PDAC develops from 3 precursor lesions, pancreatic intraepithelial lesions(PanIN), intraductual papillary mucinous neoplasm(IPMN), and mucinous cystic neoplasm. Early detection and surgical resection can increase PDAC 5-year survival rate from 6% for Stage Ⅳ to 50% for Stage Ⅰ. To date, there are no reliable biomarkers that can detect PDAC. MicrorNAs(mirNA) are small noncoding rNAs(18-25 nucleotides) that regulate gene expression by affecting translation of messenger rNA(mrNA). A large body of evidence suggests that mirNAs are dysregulated in various types of cancers. MirNA has been profiled as a potential biomarker in pancreatic tumor tissue, blood, cyst fluid, stool, and saliva. Four mi rNA biomarkers(mir-21, mir-155, mir-196, and mir-210) have been consistently dysregulated in PDAC. Mir-21, mir-155, and mir-196 have also been dysregulated in IPMN and PanIN lesions suggesting their use as early biomarkers of this disease. In this review, we explore current knowledge of mirNA sampling, mir NA dysregulation in PDAC and its precursor lesions, and advances that have been made in using mirNA as a biomarker for PDAC and its precursor lesions.

关键词： Pancreatic cancer MicrorNA biomarkers Pancreatic intraepithelial lesions Intraductal papillarymucinous neoplasm

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Impact analysis of compressor rotor blades of an aircraft engine

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Frontiers of Structural and Civil Engineering 2019年第3期13卷 505-514页

作者： Y b SUDHIr SASTrY b G KIrOS F HAILU r bUDArAPU Department of Aeronautical Engineering Institute of Aeronautical EngineeringDundigalHyderabad 500043India Department of Aeronautical Engineering College of EngineeringDefense UniversityBishoftu 1041Ethiopia School of Mechanical Sciences Indian Institute of Technology BhubaneswarBhubaneswar 752050India

Frequent failures due to foreign particle impacts are observed in compressor blades of the interceptor fighter MIG-23 aircraft engines in the Ethiopian air force,supplied by the Dejen Aviation *** this paper,we made an attempt to identify the causes of failure and hence recommend the suitable materials to withstand the foreign particle *** and stress analysis of one of the recently failed MIG-23 gas turbine compressor blades made up of the following Aluminum based alloys:6061-T6,7075-T6,and 2024-T4,has been performed,apart from the impact analysis of the rotor blades hit by a granite *** numerical results are correlated to the practical *** on the modal,stress and impact analysis and the material properties of the three considered alloys,alloy 7075-T6 has been recommended as the blade material.

关键词： axial flow compressor rotor and stator blades aircraft engine stress and impact analysis aluminum alloys

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