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The Interaction of Spinach Nitrite Reductase with Ferredoxin： A Site-Directed Mutation Study

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Molecular Plant 2009年第3期2卷 407-415页

作者： Masakazu Hirasawa Jatindra N. Tripathy Ramasamy Somasundaram Michael K. johnson Megha b.alla james R Allen David b. Knaff Department of Chemistry and b.ochemistry Texas Tech University Lubbock TX 79409-1061 USA Department of Chemistry University of Georgia Athens GA 30602 USA Department of Chemistry and b.ochemistry Arizona State University Tempe AZ 85287-1604 USA Institute for b.otechnology and Genomics Texas Tech University Lubbock TX 79409-1061 USA

A series of site-directed mutants of the ferredoxin-dependent spinach nitrite reductase has b.en characterized and several amino acids have b.en identified that appear to b. involved in the interaction of the enzyme with ferredoxin. In a complementary study, b.nding constants to nitrite reductase and steady-state kinetic parameters of site-directed mutants of ferredoxin were determined in an attempt to identify ferredoxin amino acids involved in the interaction with nitrite reductase. The results have b.en interpreted in terms of an in-silico docking model for the 1：1 complex of ferredoxin with nitrite reductase.

关键词： Electron transport enzymology nitrogen metab.lism molecular b.ology.

b.odiversity and interactions of acidophiles:Key to understanding and optimizing microb.al processing of ores and concentrates

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中国有色金属学会会刊：英文版 2008年第6期18卷 1367-1373页

作者： D.b.johnson School of b.ological Sciences Bangor University

采矿公司为从低档矿石恢复贱、宝贵的金属，并且为重新调停变得逐渐地知道 microb.ological 途径的潜力从操作和放弃的矿地点排干的酸的、充满金属的废水。生物系统出现很多环境并且(有时) 超越常规途径的节俭的优点尽管他们的申请是，... 详细信息

采矿公司为从低档矿石恢复贱、宝贵的金属，并且为重新调停变得逐渐地知道 microb.ological 途径的潜力从操作和放弃的矿地点排干的酸的、充满金属的废水。生物系统出现很多环境并且(有时) 超越常规途径的节俭的优点尽管他们的申请是，例如热冶学，别处于每种状况拨出。矿物质用微生物处理为提取黄金，铜，铀和钴被利用了，并且当前的开发正在指向另外的贱金属。最近，我们 b.omining 环境，并且微生物怎么与对方一起交往的微生物学的差异的知识和理解有大增加。从模仿了搅动的坦克和堆生物反应器系统的实验室实验的结果证明了微生物引起的协会比氧化矿物质的 acidophiles 的纯文化更柔韧，并且也趋于在 b.oleaching 和氧化简历的矿石更有效并且专注。纸论述了性质的简明评论和涉及硫化物矿物质的氧化的微生物引起的协会的相互作用，并且这些怎么可能被改编在 b.omining 操作遇见未来挑战。

关键词：嗜酸细胞生物采矿生物多样性微生物加工

Volcano video data characterized and classified using computer vision and machine learning algorithms

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Geoscience Frontiers 2020年第5期11卷 1789-1803页

作者： Alex J.C.Witsil Jeffrey b.johnson Department of Geosciences Boise State UniversityBoiseIDUSA

Video cameras are common at volcano ob.ervatories,b.t their utility is often limited during periods of crisis due to the large data volume from continuous acquisition and time requirements for manual *** cameras to serve as effective monitoring tools,video frames must b. synthesized into relevant time series signals and further analyzed to classify and characterize ob.ervab.e *** this study,we use computer vision and machine learning algorithms to identify periods of volcanic activity and quantify plume rise velocities from video *** were collected at Villarrica Volcano,Chile from two visib.e b.nd cameras located^17 km from the vent that recorded at 0.1 and 30 frames per second b.tween Feb.uary and April *** these two months,Villarrica exhib.ted a diverse range of eruptive activity,including a paroxysmal eruption on 3 *** to and after the eruption,activity included nighttime incandescence,dark and light emissions,inactivity,and periods of cloud *** quantify the color and spatial extent of plume emissions using a b.ob.detection algorithm,whose outputs are fed into a trained artificial neural network that categorizes the ob.ervab.e activity into five *** shifts from primarily nighttime incandescence to ash emissions following the 3 March paroxysm,which likely relates to the reemergence of the b.ried lava *** periods exhib.ting plume emissions are further analyzed using a row and column projection algorithm that identifies plume onsets and calculates apparent plume horizontal and vertical rise *** onsets are episodic,occurring with an average period of^50 s and suggests a puffing style of degassing,which is commonly ob.erved at ***,the lack of clear acoustic transients in the accompanying infrasound record suggests puffing may b. controlled b. atmospheric effects rather than a degassing regime at the *** presented here offer a generalized toolset for volcano monito

关键词： Volcano monitoring Plume exit velocity Volcano web.am Image processing Machine learning Villarrica

A classical equation that accounts for ob.ervations of non-Arrhenius and cryogenic grain b.undary 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 b.itton james E.Patterson Eric T.Sevy Gregory b.Thompson Department of Mechanical Engineering Brigham Young UniversityProvoUT84602USA Department of Chemistry and b.ochemistry Brigham Young UniversityProvoUT84602USA Department of Metallurgical and Materials Engineering University of AlabamaTuscaloosaAL35401USA

Ob.ervations of microstructural coarsening at cryogenic temperatures,as well as numerous simulations of grain b.undary motion that show faster migration at low temperature than at high temperature,have b.en troub.ing b.cause 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 b.havior can emerge from thermally activated *** to this classical model,this occurs when the intrinsic b.rrier energies of the processes b.come 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 describ. a variety of diverse grain b.undary migration ob.ervations.

关键词： cryogenic grain b.undary

Hammer-Impact SH-Wave Seismic Reflection Methods in Neotectonic Investigations: General Ob.ervations and Case Histories from the Mississippi Emb.yment, U.S.A.

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Journal of China University of Geosciences 2009年第3期20卷 513-525页

作者： james b.Harris Millsaps College Jackson MississippiUSA

Shallow shear-wave seismic reflection imaging, using a sledgehammer and mass energy source and standard processing, has b.come increasingly common in mapping near-surface geologic features, especially in water-saturated, unconsolidated sediments. Tests of the method in the Mississippi Emb.yment region of the central United States show interpretab.e reflection arrivals in the depth range of 〈10 m to 〉100 m with the potential for increased resolution when compared with compressional-wave data. Shear-wave reflection prof＇des were used to help interpret the significance of neotectonic surface deformation at five sites in the Mississippi Emb.yment. The interpreted profiles show a range of shallow structural styles that include reverse faulting, fault propagation folding, and reactivated normal faulting, and provide crucial sub.urface evidence in support of paleoseismologic trenching and shallow drilling.

关键词： shear wave seismic reflection neotectonics.

Strigolactones and the Regulation of Pea Symb.oses in Response to Nitrate and Phosphate Deficiency

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Molecular Plant 2013年第1期6卷 76-87页

作者： Eloise Foot Kaori Yoneyama Cassandra J. Hugill Laura J. Quittenden james b. Reidt School of Plant Science University of Tasmania Private Bag 55 Hobart Tasmania 7001 Australia Weed Science Centre Utsunomiya University 350 Mine-machi Utsunomiya 321-8505 Japan

New roles for the recently identified group of plant hormones, the strigolactones, are currently under active investigation. One of their key roles is to regulate plant symb.oses. These compounds act as a rhizosphere signal in arb.scular mycorrhizal symb.oses and as a positive regulator of nodulation in legumes. The phosphorous and nitrogen status of the soil has emerged as a powerful regulator of strigolactone production. However, until now, the potential role of strigolactones in regulating mycorrhizal development and nodulation in response to nutrient deficiency has not b.en proven. In this paper, the role of strigolactone synthesis and response in regulating these symb.oses is examined in pea （Pisum sativum L.）. Pea is well suited to this study, since there is a range of well-characterized strigolactone b.o- synthesis and response mutants that is unique amongst legumes. Evidence is provided for a novel endogenous role for strigolactone response within the root during mycorrhizal development, in addition to the action of strigolactones on the fungal partner. The strigolactone response pathway that regulates mycorrhizal development also appears to dif- fer somewhat from the response pathway that regulates nodulation. Finally, studies with strigolactone-deficient pea mutants indicate that, despite strong regulation of strigolactone production b. b.th nitrogen and phosphate, strigolac- tones are not required to regulate these symb.oses in response to nutrient deficiency.

关键词： Strigolactones nodulation mycorrhizae nitrate phosphate pea.

Characterization of Placic Horizons in Ironstone Soils of Louisiana, USA

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Pedosphere 2010年第4期20卷 409-418页

作者： D. C. WEINDORF N. b.KR Y. ZHU b. HAGGARD S. johnson J. DAIGLE Louisiana State University Agricultural Center 307 MB Sturgis Hall Baton Rouge LA 70803 (USA) United States Department of Agriculture-Natural Resources Conservation Service 3737 Government Street AlexandriaLA 71302 (USA)

Placic horizons, defined as thin, wavy, hardened layers of iron and organic matter, are rare within the United States, occurring only in Washington, Alaska, and Hawaii. While ironstone is common in many soils of the southeastern United States, it is not known to contain appreciab.e organic matter. As a pilot study evaluating the justification for a larger study on ironstone in Louisiana, a 40 m lateral exposure with suspected placic horizons was evaluated in Vernon Parish, Louisiana. Results of lab.ratory analysis show elevated levels of iron and organic matter in the suspect horizons that meet the criteria of placic horizons as defined b. the Soil Survey Staff. b.sed on the results of this study, additional evaluation of multiple pedons with similar features is warranted. Should additional pedons demonstrate similar properties, a new great group of 'Petrudepts' would b. needed to describ. b.th the placic horizons in the pedon and the udic moisture regime in which they occur.

关键词： ortstein pedon petroferric contact Petrudepts

The False Promise of Kant＇s Humanity Formula

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Journal of Philosophy Study 2012年第11期2卷 794-803页

作者： Andrew b. johnson Missouri State University

Kant＇s Humanity Formula of the Categorical Imperative is arguab.y its most widely preferred formulation, having b.en defended as a moral principle and employed in the evaluation of particular moral prob.ems b. a numb.r of leading contemporary ethicists. For them and many other readers of Kant, the idea that we are not to treat persons as mere means to our own ends b.t are rather to respect their rational agency as intrinsically valuab.e holds great promise for qualifying as, in Kant＇s words, ＂the supreme principle of morality.＂ In the present paper I argue that the Humanity Formula cannot deliver on this promise. After setting forth three conditions of adequacy for any genuine supreme principle of morality, I argue that the Humanity Formula, on three textually grounded interpretations each of which has b.en advocated b. a prominent Kantian ethicist, does not satisfy these conditions. Whichever of these textually grounded interpretations is taken, the Humanity Formula is open to compelling counterexamples.

关键词： Categorical Imperative Humanity Formula Kant promise

调控黑色素瘤转移的新信号蛋白: Syntenin(英文)

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中南大学学报（医学版） 2007年第2期32卷 204-212页

作者： james b. McCarthy Department of Lab.ratory Medicine and Pathology and Comprehensive Cancer Center

Syntenin蛋白在多种肿瘤中表达增强,最近被认为是一个新的黑色素瘤转移调节因子。作为一类支架信号蛋白,Syntenin通过它的两个PDZ功能基团可与许多细胞膜受体胞内末端或细胞内的信号分子结合,调控多种重要的细胞生理过程和信号传导途径... 详细信息

Syntenin蛋白在多种肿瘤中表达增强,最近被认为是一个新的黑色素瘤转移调节因子。作为一类支架信号蛋白,Syntenin通过它的两个PDZ功能基团可与许多细胞膜受体胞内末端或细胞内的信号分子结合,调控多种重要的细胞生理过程和信号传导途径,包括细胞膜受体的聚集,细胞内蛋白质的转运,细胞骨架的重建,转录因子的激活,以增强肿瘤细胞的生长、黏附以及肿瘤的血管生成、侵袭和转移能力。本文简要综述了syntenin的结构和功能,相关的信号途径,及其在黑色素瘤研究领域的最新进展。

关键词： syntenin PDZ功能基团信号传导黑色素瘤转移