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Journal of Integrative Plant Biology 2012年第1期54卷 15-32页

作者： Hamlet Avilés-Arnaut john Paul Délano-Frier Center of Research and Advanced studies (Cinvestav) at Irapuato:Unit for Plant Biotechnology and Genetic Engineering

Tomato systemin is a bioactive peptide that regulates the systemic activation of wound-responsive genes. It is released from its 200 amino acid precursor called prosystemin. Initial tissue-localization and hormone-induced expression assays indicated that the tomato prosystemin gene （sIPs） accumulates mainly in floral tissues and in response to exogenous abscisic acid and methyl jasmonate （meJA） treatments, respectively. Later, the promoter regions of the Ps gene in tomato （solanum lycopersicum L. cv. Castlemart）, pepper （Capsicum annuum） and potato （solanum tuberosum） were isolated and an in silico analysis of the sIPs promoter revealed an over-representation of stress- and meJA-responsive motifs. A subsequent 5＇ deletion analysis of the sIPs promoter fused to the/^-glucuronidase reporter （GUs） gene showed that the -221 to ＋40 bp proximal sIPs promoter region was sufficient to direct the stigma, vascular bundle-specific and meJA-responsive expression of GUs in transgenic tobacco plants. Important ***-specific, light- and meJA-responsive cis-elements were also present in this region. These findings provide relevant information regarding the transcriptional regulation mechanisms of the sIPs promoter operating in transgenic tobacco plants. They also suggest that its Ussue-specificity and inducible nature could have wide applicability in plant biotechnology.

关键词： cis-regulatory elements flower specific jasmonic acid methyl jasmonate promoter analysis prosystemin wound-responsive genes.

Co-Doped ZnO Nanoparticles:structural,morphological,Optical,magnetic and Antibacterial studies

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Journal of materials science & Technology 2014年第11期30卷 1108-1117页

作者： N.mohamed Basith J.Judith Vijaya L.john Kennedy m.Bououdina s.Jenefar V.Kaviyarasan Catalysis & Nanomaterials Research Laboratory Department of ChemistryLoyola College (Autonomous) P.G.& Research Department of Chemistry The New College (Autonomous) materials Division School of Advanced SciencesVellore Institute of Technology (VIT) UniversityChennai Campus Nanotechnology Centre University of BahrainPO Box 32038Bahrain Department of Physics College of ScienceUniversity of BahrainPO Box 32038Bahrain Centre for Advanced studies in Botany University of Madras

Un-doped and Co-doped ZnO nanoparticles （NPs） with different weight ratios （0.5, 1.0, 1.5, and 2.0 wt% of Co） were synthesized by a facile and rapid microwave-assisted combustion method using urea as a fuel. The prepared NPs were characterized by X-ray diffraction （XRD）, high resolution scanning electron microscopy （HR-sEm）, energy dispersive X-ray analysis （EDX）, diffuse reflectance spectroscopy （DRs）, photoluminescence （PL） spectroscopy and vibrating sample magnetometry （Vsm）. XRD patterns refined by the Rietveld method indicated that Co-doped ZnO had a single pure phase with wurtzite structure suggesting that Co^2＋ ions would occupy Zn^2＋ ionic sites within the ZnO crystal lattice. Interestingly, the morphology was found to convert substantially from grains to nanoparticles with close-packed periodic array of hexagonal-like shape and then into randomly distributed spherical NPs with the variation of Co-content. The optical band gap estimated using DRs was found to be red-shifted from 3.22 eV for the un-doped ZnO NPs then decrease up to 2.88 eV with increasing Co-content. PL spectra showed a strong green emission band thus confirming the formation of pure single ZnO phase. magnetic studies showed that Co-doped ZnO NPs exhibited room temperature ferromagnetism （RTFm） and that the saturation magnetization attained a maximum value of 2.203 × 10^-3 emu/g for the highest Co-content. The antibacterial studies performed against a set of bacterial strains showed that the 2.0 wt% Co-doped ZnO NPs possessed a greater antibacterial effect.

关键词： Nanoparticles Optical properties Ferromagnetism Antibacterial activity

magnetic resonance studies of a gas-solids fluidised bed:Jet-jet and jet-wall interactions

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Particuology 2010年第6期8卷 617-622页

作者： meenal Pore Daniel J.Holland Thusara C.Chandrasekera Christoph R.müller Andrew J.sederman john s.Dennis Lynn F.Gladden john F.Davidson Department of Chemical Engineering and Biotechnology University of CambridgePembroke StreetCambridgeCB2 3RAUK Department of mechanical and Process Engineering ETH ZurichSonneggstrasse 38092 ZurichSwitzerland

magnetic resonance imaging （mRI） gave images of air jets from orifices in the distributor plate of a bed of poppy seeds. Attention focused on two features：（1） The interaction between nearby vertical jets from two, three or four orifices; （2） Wall effects, where one or more orifices created vertical jets near the vertical wall of the cylinder containing the particle bed. The results show that nearby jets are mutually attracted. Likewise a jet near a wall bends out of the vertical, towards the wall, For multiple adjacent jets, the jet lengths show dependence on orifice layout： the lengths are in reasonable agreement with published measurements, by other methods, for single jets. The mRI gives three-dimensional images of the single jets and of multiple jets, separate or merging.

关键词： Fluidised bed mRI Jets Distributor design

Carbon dioxide enrichment affected flower numbers transiently and increased successful post-pollination development stably but without altering final acorn production in mature pedunculate oak (Quercus robur L.)

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Journal of Forestry Research 2024年第4期35卷 1-12页

作者： Ryan mcClory Richard H.Ellis martin Lukac Jo Clark Carolina mayoral Kris m.Hart Andrew R.G.Plackett A.Rob macKenzie school of Agriculture Policy and DevelopmentUniversity of ReadingAgricultureEarley GateWhiteknights RoadPO Box 237Reading RG66EUUK Faculty of Forestry and Wood sciences Czech University of Life Sciences PraguePrague 165000Czechia Future Trees Trust Harwell Innovation CentreBuilding 173Curie AvenueHarwellOxford OX110QGUK Birmingham Institute of Forest Research University of BirminghamEdgbastonBirmingham B152TTUK school of Biosciences University of BirminghamEdgbastonBirmingham B152TTUK school of Geography Earth and Environmental SciencesUniversity of BirminghamEdgbastonBirmingham B152TTUK

Acorn production in oak(Quercus spp.)shows considerable inter-annual variation,known as masting,which provides a natural defence against seed predators but a highly-variable supply of acorns for uses such as in commercial tree planting each *** emissions of greenhouse gases have been very widely reported to influence plant growth and seed or fruit size and quantity via the‘fertilisation effect’that leads to enhanced *** examine if acorn production in mature woodland communities will be affected by further increase in CO_(2),the contents of litter traps from a Free Air Carbon Enrichment(FACE)experiment in deciduous woodland in central England were analysed for numbers of flowers and acorns of pedunculate oak(Quercus robur L.)at different stages of development and their predation levels under ambient and elevated CO_(2) ***-annual variation in acorn numbers was considerable and cyclical between 2015 and 2021,with the greatest numbers of mature acorns in 2015,2017 and 2020 but almost none in *** numbers of flowers,enlarged cups,immature acorns,empty acorn cups,and galls in the litter traps also varied amongst years;comparatively high numbers of enlarged cups were recorded in 2018,suggesting *** at this site is a fruit maturation masting species(i.e.,the extent of abortion of pollinated flowers during acorn development affects mature acorn numbers greatly).Raising the atmospheric CO_(2) concentration by 150μL L^(−1),from early 2017,increased the numbers of immature acorns,and all acorn evidence(empty cups+immature acorns+mature acorns)detected in the litter traps compared to ambient controls by 2021,but did not consistently affect the numbers of flowers,enlarged cups,empty cups,or mature *** number of flowers in the elevated CO_(2) plots’litter traps was greater in 2018 than 2017,one year after CO_(2) enrichment began,whereas numbers declined in ambient *** with CO_(2) also increased the number o

关键词： Quercus robur L. Acorns masting Pedunculate oak Carbon dioxide

Analyzing machine learning models to accelerate generation of fundamental materials insights

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npj Computational materials 2019年第1期5卷 858-866页

作者： mitsutaro Umehara Helge s.stein Dan Guevarra Paul F.Newhouse David A.Boyd john m.Gregoire Joint Center for Artificial Photosynthesis California Institute of TechnologyPasadenaCA 91125USA Future mobility Research Department Toyota Research Institute of North AmericaAnn ArborMI 48105USA

machine learning for materials science envisions the acceleration of basic science research through automated identification of key data relationships to augment human interpretation and gain scientific understanding.A primary role of scientists is extraction of fundamental knowledge from data,and we demonstrate that this extraction can be accelerated using neural networks via analysis of the trained data model itself rather than its application as a prediction *** neural networks excel at modeling complex data relationships in multi-dimensional parameter spaces,such as that mapped by a combinatorial materials science *** a performance metric in a given materials space provides direct information about(locally)optimal materials but not the underlying materials science that gives rise to the variation in *** building a model that predicts performance(in this case photoelectrochemical power generation of a solar fuels photoanode)from materials parameters(in this case composition and Raman signal),subsequent analysis of gradients in the trained model reveals key data relationships that are not readily identified by human inspection or traditional statistical *** interpretation of these key relationships produces the desired fundamental understanding,demonstrating a framework in which machine learning accelerates data interpretation by leveraging the expertize of the human *** also demonstrate the use of neural network gradient analysis to automate prediction of the directions in parameter space,such as the addition of specific alloying elements,that may increase performance by moving beyond the confines of existing data.

关键词： neural prediction desired

Association between admission haematocrit and mortality among men with acute ischaemic stroke

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stroke & Vascular Neurology 2018年第3期3卷 160-168页

作者： Jason J sico Laura J myers Brenda J Fenton john Concato Linda s Williams Dawn m Bravata Neurology service VA Connecticut Healthcare SystemWest HavenConnecticutUSA Department of Neurology Center for NeuroEpidemiological and Clinical Neurological ResearchYale University School of MedicineNew HavenConnecticutUSA Department of Internal medicine Yale University School of MedicineNew HavenConnecticutUSA Clinical Epidemiology Research Center(CERC) VA Connecticut Healthcare SystemWest HavenConnecticutUSA Pain Research InformaticsMultimorbidities and Education(PRIME)Center of InnovationVA Connecticut Healthcare SystemWest HavenConnecticutUSA Communication and the HsR&D stroke Quality Enhancement Research Initiative(QUERI) Richard L Roudebush VA Medical CenterIndianapolisIndianaUSA VA Health services Research and Development(HsR&D) Center for Healthcare InformaticsRichard L Roudebush VA Medical CenterIndianapolisIndianaUSA Division of Chronic Disease Epidemiology Yale School of Public HealthWest HavenConnecticutUSA medical service VA Connecticut Healthcare SystemWest HavenConnecticutUSA Regenstrief Institute IndianapolisIndianaUSA Department of Neurology Indiana University School of MedicineIndianapolisIndianaUSA Department of Internal medicine Indiana University School of MedicineIndianapolisIndianaUSA

Objective Anaemia is associated with higher mortality among patients with non-stroke cardiovascular conditions;less is known regarding the relationship between anaemia and mortality among patients with acute ischaemic *** medical records were abstracted for n=3965 veterans from 131 Veterans Health Administration facilities who were admitted with ischaemic stroke in fiscal year *** values within 24 hours of admission were classified as≤27%,28%-32%,33%-37%,38%-42%,43%-47% or≥48%.multivariate logistic regression was used to examine the relationship between anaemia and in-hospital,30-day,6-month and 1-year mortality,adjusting for age,medical comorbidities,modified Acute Physiology and Chronic Health Evaluation-III and stroke *** factors were calculated to standardise comparisons between haematocrit tier and other *** Among n=3750 patients included in the analysis,the haematocrit values were≤27%in 2.1%(n=78),28%-32% in 6.2%(n=234),33%-37%in 17.9%(n=670),38%-42% in 36.4%(n=1366),43%-47% in 28.2%(n=1059)and≥48% in 9.1%(n=343).Patients with haematocrit≤27%,compared with patients in the 38%-42% range,were more likely to have died across all follow-up intervals,with statistically significant adjusted ORs(aORs)ranging from 2.5 to *** with polycythaemia(ie,haematocrit≥48%)were at increased risk of in-hospital mortality(aOR=2.9;95%CI 1.4 to 6.0),compared with patients with mid-range admission *** differences between patients receiving and not receiving blood transfusion limited our ability to perform a propensity *** factors in the 1-year mortality model were 0.46(severe anaemia),0.06(cancer)and 0.018(heart disease).Conclusions Anaemia is independently associated with an increased risk of death throughout the first year post stroke;high haematocrit is associated with early poststroke *** anaemia is associated with 1-year mortality to a greater degree than cancer or heart dise

关键词： mortality admitted transfusion

Gas flow in rotary kilns

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Particuology 2010年第6期8卷 613-616页

作者： Patrick R.Davies michael J.s.Norton D.Ian Wilson john F.Davidson David m.scott Department of Chemical Engineering and Biotechnology University of CambridgePembroke StreetCambridgeCB2 3RAUK

This paper describes an experimental investigation on the flow characteristics within a rotating cylinder containing a rolling bed of sand. The axis of the cylinder was horizontal and there was no axial bulk flow of particles. The velocity field of the gas flowing through the cylinder was measured by hot-wire anemometry. The measurements indicate that the velocity field is asymmetric with respect to a diameter perpendicular to the granular bed. CFD calculations confirm this finding. The gas velocity profiles are crucial in determining heat transfer from gas to solid.

关键词： Rotating cylinderVelocity profile

Predation changes the shape of thermal performance curves for population growth rate

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Current Zoology 2016年第5期62卷 501-505页

作者： Thomas m. LUHRING john P. DELONG school of Biological sciences University of Nebraska Lincoln Nebraska 68588 USA

Ectotherms generally demonstrate nonlinear changes in performance （e.g., movement speed, indi- vidual growth, population growth） as a function of temperature that are characterized by thermal performance curves （TPC）. Predation risk elicits phenotypic and behavioral changes that likewise impact performance measures. We tested whether exposure to predation Orthocyclops modestus impacts the maximum population growth rate （rmax） TPC of the protist Paramecium aurelia. We fit predator and non-predator exposed P. aurelia population growth rates to a function previously shown to best describe Paramecium population growth rate TPC＇s （Lactin-2） and compared subse- quent parameter estimates between curves. For Paramecium exposed to predation risk, maximum population growth increased more rapidly as temperatures rose and decreased more rapidly as temperatures fell compared to the initial temperature. The area under each TPC curve remained ap- proximately the same, consistent with the idea of a trade-off in performance across temperatures. Our results indicate TPCs are flexible given variation in food web context and that trophic inter- actions may play an important role in shaping TPCs. Furthermore, this and other studies illustrate the need for a mechanistic model of TPCs with parameters tied to biologically meaningful properties.

关键词： paramecium phenotypic plasticity predation reaction norm temperature thermal performance curve.

secure data networks for electrical distribution applications

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Journal of modern Power systems and Clean Energy 2015年第3期3卷 447-455页

作者： David m.LAVERTY john B.O’RAW Kang LI D.john mORROW school of EEECs Queen’s University Belfast125 Stransmillis RoadBelfast BT95AHUK

smart Grids are characterized by the application of information communication technology(ICT)to solve electrical energy *** power networks span large geographical areas,thus a necessary component of many smart Grid applications is a wide area network(WAN).For the smart Grid to be successful,utilities must be confident that the communications infrastructure is *** paper describes how a WAN can be deployed using WimAX radio technology to provide high bandwidth communications to areas not commonly served by utility communications,such as generators embedded in the distribution network.A planning exercise is described,using Northern Ireland as a case *** suitability of the technology for real-time applications is assessed using experimentally obtained latency data.

关键词： Telecoms Latency WimAX security

Potential of capillary electrophoresis mass spectrometry for the characterization and monitoring of amine-derivatized naphthenic acids from oil sands process-affected water

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Journal of Environmental sciences 2016年第11期28卷 203-212页

作者： matthew s.macLennan Cai Tie Kevin Kovalchik Kerry m.Peru Xinxiang Zhang john V.Headley David D.Y.Chen Department of Chemistry University of British Columbia Vancouver BC V6T 1Z1 Canada. state Key Laboratory of Bioactiue substance and Function of Natural medicines Institute of Materia Medica Peking Union Medical College &Chinese Academy of Medical Sciences Beijing 100050 China Water science and Technology Directorate Science and Technology Branch Environment and Climate Change Canada SaskatoonSK S7N 3H5 Canada College of Chemistry and molecular Engineering Peking University Beijing 100871 China

Capillary electrophoresis coupled to mass spectrometry（CE–ms） was used for the analysis of naphthenic acid fraction compounds（NAFCs） of oil sands process-affected water（OsPW）. A standard mixture of amine-derivatized naphthenic acids is injected directly onto the CE column and analyzed by CE–ms in less than 15 min. Time of flight ms analysis（TOFms）, optimized for high molecular weight ions, showed NAFCs between 250 and 800 m/z. With a quadrupole mass analyzer, only low-molecular weight NAFCs（between 100 and 450 m/z） are visible under our experimental conditions. Derivatization of NAFCs consisted of two-step amidation reactions mediated by 1-ethyl-3-（3-dimethylaminopropyl）carbodiimide（EDC）, or mediated by a mixture of EDC and N-hydroxysuccinimide, in dimethyl sulfoxide, dichloromethane or ethyl acetate. The optimum background electrolyte composition was determined to be 30%（V/V） methanol in water and 2%（V/V） formic acid. NAFCs extracted from OsPW in the Athabasca oil sands region were used to demonstrate the feasibility of CE–ms for the analysis of NAFCs in environmental samples, showing that the labeled naphthenic acids are in the mass range of 350 to 1500 m/z.

关键词： Capillary electrophoresis mass spectrometry Electrospray ionization Carbodiimide Oil sands process-affected water Naphthenic acids