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Reduced nitrogen availability during growth improves quality in red oak lettuce leaves by minimizing nitrate content, and increasing antioxidant capacity and leaf mineral content

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Agricultural Sciences 2011年第4期2卷 477-486页

作者： Dario Stefanelli Sonja Winkler rod jones 不详

Overuse of N in lettuce production can lead to environmental problems caused by leaching and the accumulation of harmful nitrates in edible tissues. This study investigated the effect of applied nitrogen (N) concentrations between 40 and 2400 mg·L–1 on growth, nitrate accumulation, mineral leaf content, and antioxidant capacity in Oak Leaf lettuce cv. “Shiraz” grown under hydroponic conditions in Australia. Yield (g FW) increased with nitrogen (N) application rate up to 1200 mg·L–1, as did leaf N content, while C:N declined. Nitrogen Utilization Efficiency (NUtE) increased rapidly from 40 to 75 mg·L–1 applied N, leveling at 150 mg·L–1 with no subsequent effect of N concentrations between 400 and 2400 mg·L–1. Nitrate content rose significantly with increased N, particularly at 1200 and 2400 mg·L–1. Leaf total plant phenolic content (TPP) and antioxidant capacity (measured by ferric reducing antioxidant power—FRAP) were both maximal at 75 and 400 mg·L–1 applied N, while highest oxygen radical absorption capacity (ORAC) values were found in leaves supplied with low N (40 to 400 mg·L–1). Applied N as calcium nitrate also significantly affected leaf mineral content as B, Mg, Mn, and Zn significantly decreased with increasing N. These results indicate that N applications of 1200 mg·L–1 or higher can result in reduced antioxidant capacity and mineral content in lettuce leaves.

关键词： Lactuca sativa L. Hydroponic Phenolic Content Zinc Manganese Magnesium

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Reduction in Nitrogen Prior to Harvest Increases Phenolic Content of Baby Red Lettuce Leaves

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Agricultural Sciences 2014年第6期5卷 546-554页

作者： Dario Stefanelli Sonja Winkler Christine Frisina rod jones Department of Environment and Primary Industries Agriculture Research Division Victoria Australia

This study investigated baby red lettuce leaves grown in an inert media and fertigated with 300 or 1000 mg·L-1 CaNO3-N (19% Ca;15.5% N), and the effects of altering CaNO3-N concentrations in the last 7 days prior to harvest on yield, antioxidant capacity, TPP and vitamin C content. Plants receiving 1000 mg·L-1 CaNO3-N had a significantly higher leaf FW than those fertilized with 300 mg·L-1 CaNO3-N after both 21 and 28 days. Pulsing plants with 1000 mg·L-1 CaNO3-N for 7 days after 21 days at 300 mg·L-1 CaNO3-N resulted in a significant increase in FW of 14%, compared with plants receiving 300 mg·L-1 CaNO3-N. After 28 days plants fertilized with nitrogen at 300 mg·L-1 CaNO3-N were significantly higher in TPP than those fertilized with 1000 mg·L-1 CaNO3-N. While there was no significant effect on TPP of a 7-day 1000 mg·L-1 CaNO3-N pulse added to 300 mg·L-1 CaNO3-N, a 7-day pulse of 300 mg·L-1 CaNO3-N added to 1000 mg·L-1 CaNO3-N resulted in a significant increase in TPP. These results indicate that reducing the N availability for 7 days prior to harvest can result in a significant increase in plant phenolic content with no adverse effect on yield.

关键词： Yield Production Vitamin C Antioxidant Capacity

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桂中晚二叠世碳酸盐岩型煤系高有机硫煤的矿物学和地球化学研究

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煤炭学报 2006年第6期31卷 770-775页

作者：邵龙义鲁静 Tim jones rod Gayer 尚潞君深志军张鹏飞中国矿业大学(北京)煤炭资源与安全开采国家重点实验室北京100083 英国Cardiff大学地球海洋及宇宙科学学院

应用带能谱的扫描电镜（SEM—EDX）、X射线衍射（XRD）、X射线荧光（XRF）等方法研究了桂中合山煤田合山组灰分小于50％的煤层样品矿物组成、常量和微量元素的地球化学特征．结果表明：合山煤中全硫含量在5．3％-11．6％之间，与惰质组... 详细信息

应用带能谱的扫描电镜（SEM—EDX）、X射线衍射（XRD）、X射线荧光（XRF）等方法研究了桂中合山煤田合山组灰分小于50％的煤层样品矿物组成、常量和微量元素的地球化学特征．结果表明：合山煤中全硫含量在5．3％-11．6％之间，与惰质组相比，有机硫更易在镜质组中富集；合山煤中的矿物有石英、方解石、白云石等，并有少量的白铁矿、伊／蒙混层黏土矿物、红磷铁矿等，结合电镜观察，认为这些矿物主要形成于泥炭堆积压实前的同生作用；同世界煤相比，W，U，Mo，Cr，V，Zr明显富集．根据微量元素同常量元素、灰分和硫分的相关性，将微量元素分为5种结合态．

关键词：碳酸盐岩型有机硫微量元素合山煤田合山组

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Computational Studies of DNA Separations in Micro-Fabricated Devices: Review of General Approaches and Recent Applications

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Advances in Chemical Engineering and Science 2017年第4期7卷 362-392页

作者： Saman Monjezi Behrouz Behdani Meyyammai B. Palaniappan James D. jones Joontaek Park Department of Chemical and Biochemical Engineering Missouri University of Science and Technology Rolla MO USA

DNA separation techniques have drawn attention because of their uses in applications such as gene analysis and manipulation. There have been many studies utilizing micro-fabricated devices for faster and more efficient separations than traditional methods using gel electrophoresis. Although many experimental studies have presented various new devices and methods, computational studies have played a pivotal role in this development by identifying separation mechanisms and by finding optimal designs for efficient separation conditions. The simulation of DNA separation methods in micro-fabricated devices requires the correct capture of the dynamics and the structure of a single polymer molecule that is being affected by an applied flow field or an electric field in complex geometries. In this work, we summarize the polymer models (the bead-spring model, the bead-rod model, the slender-body model, and the touching-bead model) and the methods, focusing on Brownian dynamics simulation, used to calculate inhomogeneous fields taking into consideration complex boundaries (the finite element method, the boundary element method, the lattice-Boltzmann method, and the dissipative particle dynamics simulation). The worm-like chain model (adapted from the bead-spring model) combined with the finite element method has been most commonly used but other models have shown more efficient and accurate results. We also review the applications of these simulation approaches in various separation methods and devices: gel electrophoresis, post arrays, capillary electrophoresis, microchannel flows, entropic traps, nanopores, and rotational flows. As more complicated geometries are involved in new devices, more rigorous models (such as incorporating the hydrodynamic interactions of DNA with solid boundaries) that can correctly capture the dynamic behaviors of DNA in such devices are needed.

关键词： DNA Separation Single Polymer Dynamics Brownian Dynamics Simulation Microfluidics Electrophoresis Entropic Trap Microchannel

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2012年伦敦奥林匹克体育场

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设计家 2012年第4期 55-60页

作者： rod Sheard Philip Johnson Megan Ashfield Sang Hoon Kim Jacob Steele Gavin Robotham Mark Craine Bill Augustyn Gurminder Saraon Tom jones Paul Foskett Belinda Goh Jamie Hay Kar Paik Soon Chinmay Potbhare Sabah Ashic Adam Doak POPULOUS

伦敦是首个第三次举办夏季奥运会的城市,组委会想表明,伦敦有能力举办一届壮观、高效、创新的奥运会和残奥会。伦敦奥运会设计中所包含的理念是＂需要为将来留下重大赛事的遗产＂,这需要对城市和场馆进行转型——挑战建筑持久性的理念... 详细信息

伦敦是首个第三次举办夏季奥运会的城市,组委会想表明,伦敦有能力举办一届壮观、高效、创新的奥运会和残奥会。伦敦奥运会设计中所包含的理念是＂需要为将来留下重大赛事的遗产＂,这需要对城市和场馆进行转型——挑战建筑持久性的理念。为了实现大型运动会体育场这一当前需求和小型场馆这一长期需求之间的平衡,Populous主张利用奥运会这一契机开发场馆设计建筑语言。

关键词：奥林匹克体育场伦敦建筑语言奥运会组委会持久性场馆运动会

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高牛尾草的选育和栽培品种(续)

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湖北畜牧兽医 1981年第3期 37-46页

作者： K.H.Asay rod V.Frakes Robert C.Buckner 吴仁润中国农业科学院兰州畜牧研究所

E·成熟性效应 jones等(1973)强调了与成熟阶段和收获期有关的质量变化上的需要。在已知收获期而与生长阶段无关的消化率或其他质量特性等的选择方法中,往往对抽样时中不太成熟的植物有利。如此净得结果可获得一个晚熟品系。而与此相反... 详细信息

E·成熟性效应 jones等(1973)强调了与成熟阶段和收获期有关的质量变化上的需要。在已知收获期而与生长阶段无关的消化率或其他质量特性等的选择方法中,往往对抽样时中不太成熟的植物有利。如此净得结果可获得一个晚熟品系。而与此相反的测是当选择根据生长阶段决定时,早熟品系也就有利,这是因为它们在较早的历年行事日程进行抽样的。

关键词：牛尾草杂种狐茅杂交种栽培品种农业实验站

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