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Dehydration Kinetics of Embryonic Axes from Desiccation-sensitive Seeds:An Assessment of Descriptive models

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Journal of Integrative Plant Biology 2009年第11期51卷 1002-1007页

作者： Tobias m. Ntuli norman W. Pammenter School of Biological and Conservation Sciences University of KwaZulu-NatalWestville Campus

The response of desiccation-sensitive plant tissues to dehydration is significantly affected by dehydration conditions, particularly the rate of drying. Consequently it is important to be able to quantify drying rate. The aim of the study was to assess two models that have been proposed to describe drying kinetics, and thus to provide a quantification of non-linear drying rates, of embryonic axes excised from recalcitrant seeds. These models are an exponential drying time course, and a modified inverse relationship, respectively. For the six species investigated here the inverse function was generally found to fit drying data better than the exponential function under both rapid and slow drying conditions, and so is recommended. The rate of drying, under the conditions used here, was determined by axis size and possibly the nature of the axis outer coverings, rather than the water activity difference between the tissue and surrounding air.

关键词： desiccation drying rate recalcitrant seeds.

Accuracy assessment of real-time kinematics(RTK)measurements on unmanned aerial vehicles(UAV)for direct geo-referencing

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Geo-Spatial Information Science 2020年第2期23卷 165-181页

作者： Desta Ekaso Francesco Nex norman Kerle Department of Earth Systems Analysis ITC-Faculty of Geo-Information Science and Earth Observation of the University of TwenteEnschedeThe NetherlandsDepartment of Earth Systems AnalysisITC-Faculty of Geo-Information Science and Earth Observation of the University of TwenteEnschedeThe NetherlandsDepartment of Earth Systems AnalysisITC-Faculty of Geo-Information Science and Earth Observation of the University of TwenteEnschedeThe Netherlands

Geospatial information acquired with Unmanned Aerial Vehicles(UAV)provides valuable decision-making support in many different domains,and technological advances coincide with a demand for ever more sophisticated data *** consequence is a research and development focus on more accurately referenced images and derivatives,which has long been a weakness especially of low to medium cost UAV systems equipped with relatively inexpensive inertial measurement unit(ImU)and Global Navigation Satellite System(GNSS)*** research evaluates the positional accuracy of the real-time kinematics(RTK)GNSS on the DJI matrice 600 Pro,one of the first available and widely used UAVs with potentially surveying-grade *** a very high positional accuracy of the drone itself of 2 to 3 cm is claimed by DJI,the actual accuracy of the drone RTK for positioning the images and for using it for mapping purposes without additional ground control is not *** begin with,the actual GNSS RTK position of reference center(the physical point on the antenna)on the drone is not indicated,and uncertainty regarding this also exists among the professional user *** this study the reference center was determined through a set of experiments using the dual frequency static Leica GNSS with RTK *** RTK positioning data from the drone were then used for direct georeferencing,and its results were *** flights were carried out over a 70 x 70 m area with an altitude of 40 m above the ground,with a ground sampling distance of 1.3 *** against ground control points,the planimetric accuracy of direct georeferencing for the photogrammetric product ranged between 30 and 60 *** of direct georeferencing results showed a time delay of up to 0.28 seconds between the drone GNSS RTK and camera image acquisition affecting direct georeferencing results.

关键词： UAV GNSS RTK direct georeferencing aerial triangulation lever arm offset

Review of remote sensing and geospatial technologies in estimating rooftop rainwater harvesting (RRWH) quality

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International Soil and Water Conservation Research 2019年第3期7卷 266-274页

作者： m.sayu norman Helmi Z.m.Shafri Shattri B.mansor Badronnisa Yusuf Department of Civil Engineering Faculty of EngineeringUniversiti Putra Malaysia(UPM)43400 SerdangSelangorMalaysia Geospatial Information Science Research Centre(GISRC) Faculty of EngineeringUniversiti Putra Malaysia(UPM)43400 SerdangSelangorMalaysia Centre of Studies for Surveying Science&Geomatics Faculty of ArchitecturePlanning&SurveyingUniversiti Teknologi MARA(Perlis)02600 ArauPerlisMalaysia

Rooftop rainwater harvesting (RRWH) systems can provide low-cost decentralized water to urban and rural households that have no access to treated *** systems are considered the key strategic adoption measures for communities affected by climate *** materials,roofing conditions,roofing geometry,weather conditions,and land use/land cover (LULC) conditions can significantly affect the quality of ***,the effects of these factors on RRWH quality must be analyzed *** sensing and Geographical Information System (GIS) have been widely used in urban environmental ***,these technologies have never been used to analyze,map,and model the effect of various factors on RRWH *** review determines the research gaps in the use of geospatial technologies in estimating RRWH quality and simulate the implications of roofing materials and roofing surface conditions towards the urban *** approach for the integrated use of remote sensing and GIS to assess the quality of RRWH is also proposed.

关键词： Roofing materials Roofing conditions Spatial modeling Environmental impact Remote sensing GIS

Small-scale convection beneath oceans and continents

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Science Bulletin 2011年第13期56卷 1292-1320页

作者： SLEEP norman H. Department of Geophysics Stanford University

Small-scale convection supplies heat flow of ～17 mW m-2 to the base of stable continents where xenolith studies resolve the ***,effects of small-scale convection are difficult to resolve in ocean *** first pass,most seafloor appears to subside to an asymptote compatible with ～40 mW m-2 convective heat *** common regions are tracked by hotspots so uplift associated with ponded mantle material is an attractive *** seafloor in the North and South Atlantic continues to subside with the square root of age as expected from pure *** theory of stagnant-lid convection provides good scaling relationships for heat *** linear viscosity,heat flow is proportional to the underlying "half-space" viscosity to the 1/3 power and the temperature to change viscosity by a factor of e to the 4/3 *** formalism is easily modified to represent convection beneath a lid of highly viscous and buoyant cratonal lithosphere and to represent transient convection beneath thickening oceanic *** mantle with linear,strongly temperature-dependent,and weakly depth-dependent viscosity is compatible with both oceanic and continental *** complicated rheology may allow vigorous small-scale convection under most but not all old ocean *** viable hypotheses require poorly understood global features,including lateral variations of asthenospheric *** studies have the potential to resolve the lithosphere-asthenosphere boundary,including local variations of its depth associated with small-scale convection.

关键词： lithosphere asthenosphere ocean depth-age small-scale convection craton mantle plume

Increased Drying Rate Lowers the Critical Water Content for Survival in Embryonic Axes of English Oak (Quercus robur L.) Seeds

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Journal of Integrative Plant Biology 2011年第4期53卷 270-280页

作者： Tobias m.Ntuli William E.Finch-Savage Patricia Berjak norman W.Pammenter Plant Germplasm Conservation Research School of Biological and Conservation SciencesUniversity of KwaZulu-NatalWestville CampusPrivate Bag X54001Durban 4000South Africa Department of Life and Consumer Sciences University of South AfricaPrivate Bag X6Florida 1710JohannesburgSouth Africa Warwick HRI Warwick UniversityWellesbourneWarwick CV35 9EFUK Plant Germplasm Conservation Research School of Biological and Conservation SciencesUniversity of KwaZulu-NatalWestville

The potential to cryopreserve embryonic axes of desiccation-sensitive（recalcitrant） seeds is limited by damage during the desiccation necessary for low temperature survival,but the basis of this injury and how to reduce it is not well *** effects of drying rate on the viability,respiratory metabolism and free radical-mediated processes were therefore investigated during dehydration of Quercus robur L embryonic ***,assessed by evidence of germination and tetrazolium staining,showed a sharp decline at 0.27 and 0.8 g/g during rapid（〈12 h） or slow（3d） dehydration,*** dehydration therefore lowered the critical water content for *** any given water content rapid dehydration was associated with higher activities of the free radical processing enzymes,superoxide dismutase,catalase and glutathione reductase and lower levels of hydroperoxide and membrane *** dehydration was also associated with lower malate dehydrogenase activity,and a reduced decline in phosphofructokinase activity and in levels of the oxidized form of nicotinamide *** may have contributed to increased damage during slow dehydration,since viability declined even in hydrated storage after 3 *** results presented are consistent with rapid dehydration reducing the accumulation of damage resulting from desiccation induced aqueous-based deleterious reactions.

关键词： Quercus robur L Seeds Figure NADH

Auxin EvoDevo: Conservation and Diversification of Genes Regulating Auxin Biosynthesis, Transport, and Signaling

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molecular Plant 2019年第3期12卷 298-320页

作者： michaela Sylvia matthes norman Bradley Best Janlo m.Robil Simon malcomber Andrea Gallavotti Paula mcSteen Division of Biological Sciences Interdisciplinary Plant Group and Missouri Maize CenterUniversity of Missouri-Columbia301 Christopher Bond Life Sciences CenterColumbiaMO 65211USA Department of Biological Sciences California State UniversityLongBeachCA 90840USA Waksman Institute of microbiology Rutgers UniversityPiscatawayNJ 08854-8020USA Department of Plant Biology Rutgers UniversityNew BrunswickNJ 08901USA Present address:National Science Foundation 2415 Eisenhower AvenueAlexandriaVA 22314USA

The phytohormone auxin has been shown to be of pivotal importance in growth and development of land *** underlying molecular players involved in auxin biosynthesis, transport, and signaling are quite well understood in ***, functional characterizations of auxin-related genes in economically important crops, specifically maize and rice, are still *** this article, we comprehensively review recent functional studies on auxirelated genes in both maize and rice, compared with what is known in Arabidopsis, and highlight conservation and diversification of their functions. Our analysis is illustrated by phylogenetic analysis and publicly available gene expression data for each gene family, which will aid in the identification of auxin-related genes for future *** challenges and future directions for auxin research in maize and rice are *** in gene editing techniques provide powerful tools for overcoming the issue of redundancy in these gene families and will undoubtedly advance auxin research in crops.

关键词： auxin maize Arabidopsis rice

Effect of hybrid rice varieties on growth and development of broilers and ducks

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Animal Nutrition 2021年第1期7卷 127-133页

作者： Frederick m.Lemieux Courtney P.Villemarette Eddie K.Lyons Thomas H.Shields norman German School of Agricultural Sciences McNeese State UniversityLake CharlesLA70609United States

Three experiments(Exp.1,n=144 broilers[Ross×Ross];Exp.2,n=118 mallard ducklings[Anas platyrhynchos];and Exp.3,n=75 mature mallard ducks)were conducted to determine the effects of 3 levels of unmilled hybrid rice on growth performance and organ and gastrointestinal tract *** dietary treatments were 1)corn-soybean meal(basal),2)basal+5%hybrid rice,and 3)basal+10%hybrid rice for Exp.1 to 3,*** bird from each pen in Exp.1(n=24)and all the birds in Exp.2(n=118)and Exp.3(n=75)were randomly selected and euthanized to determine linear measurements and organ and gastrointestinal tract *** Exp.1 and 2,birds fed 10%rice experi-enced slower growth(P0.05)in ***,birds fed 5%rice had significantly increased(Pm,and jejunum weights in Exp.2,and 10%rice significantly increased(Pmilled rice to broiler and duck diets may reduce growth performance.

关键词： Hybrid rice Broiler mallard duckling mallard duck

Bonding mechanism of ultrasonic wedge bonding of copper wire on Au/Ni/Cu substrate

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中国有色金属学会会刊：英文版 2008年第1期18卷 132-137页

作者：田艳红王春青 Y.norman ZHOU State Key Laboratory of Advanced Welding Production Technology Harbin Institute of Technology microjoining Laboratory Center for Advanced Materials JoiningUniversity of Waterloo

The ultrasonic wedge bonding with d25 μm copper wire was achieved on Au/Ni plated Cu substrate at ambient *** wedge bonding mechanism was investigated by using SEm/EDX,pull test,shear test and microhardness *** results show that the thinning of the Au layer occurs directly below the center of the bonding tool with the bonding power *** interdiffusion between copper wire and Au metallization during the wedge bonding is assumed negligible,and the wedge bonding is achieved by wear action induced by ultrasonic *** ultrasonic power contributes to enhance the deformation of copper wire due to ultrasonic softening effect which is then followed by the strain hardening of the copper wedge bonding.

关键词：铜导线超声波焊接金属学磨损性能

A rationale for the development of thermally stable nanostructured CeO_2-ZrO_2-containing mixed oxides

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Journal of Rare Earths 2008年第2期26卷 136-140页

作者： Roberta Di monte Jan Kapar Heather Bradshaw Colin norman Department of Chemistry Sciences Interuniversity Consortium INCA University of Trieste Via L.Giorgieri34127 Trieste Italy mEL Chemicals P.O. Box 6 Clifton Junction SwintonManchester M27 8LS England

CeO2-ZeO2 solid solutions are extensively used as oxygen storage promoters in the current automotive three-way catalysts. High thermal stability of the textural properties is one of the most important requirements for practical application since temperatures up to 1273 K are easily experienced by these materials under real working conditions. In the present paper, we investigated how hydrothermal treatments applied to cakes of doped and undoped ZrO2-rich CeO2-ZrO2 precursors might improve the thermal stability of the final CeO2-ZrO2 solid solution. A rationale was developed that allowed to correlate the morphology of the hydrothermaUy treated cake with the thermal stability at 1273 K of the final product, which did not depend on the composition of the mixed oxides.

关键词： CeO2-ZrO2 mixed oxides CeO2-ZrO2 solid solution CeO2-ZrO2 mixed oxides, thermal stability of three-way catalysts oxygen storage capacity rare earths