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Sub-Compartmental Organization of Golgi-Resident N-Glycan Processing Enzymes in Plants

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Molecular Plant 2011年第2期4卷 220-228页

作者： Jennifer Schoberer Richard Strasser School of Life Sciences Oxford Brookes University Headington Campus Gipsy Lane Oxford OX3 OBP UK Department of Applied Genetics and Cell Biology University of Natural Resources and Life Sciences Vienna Austria

In all eukaryotes, the Golgi apparatus is the main site of protein glycosylation. It is widely accepted that the glycosidases and glycosyltransferases involved in N-glycan processing are found concentrated within the Golgi stack where they provide their function. This means that enzymes catalyzing early steps in the processing pathway are located mainly at the cis-side, whereas late-acting enzymes mostly locate to the trans-side of the stacks, creating a non-uniform distribution along the cis-trans axis of the Golgi. There is compelling evidence that the information for their sorting to specific Golgi cisternae depends on signals encoded in the proteins themselves as well as on the trafficking machinery that recognizes these signals and it is believed that cisternal sub-compartmentalization is achieved and maintained by a combination of retention and retrieval mechanisms. Yet, the signals, mechanism（s）, and molecular factors involved are still unknown. Here, we address recent findings and summarize the current understanding of this fundamental process in plant cell biology.

关键词： Endomembrane system Golgi apparatus glycosylation glycosyltransferase.

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

Energy shift： decline of easy oil and restructuring of eo-politics

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Frontiers in Energy 2016年第3期10卷 260-267页

作者： Oliver R. INDERWILDI David A. KING Smith School of Enterprise and the Environment University of OxfordOxford OX1 3QY United Kingdom

This paper critically assesses the geopolitical and geo-economic impact of novel fuel resources on both resource exporters and importers. Presently, very strong political and economic forces drive the utilisation of domestic, unconventional oil and gas recovery in the West as these enhance energy security and ease balance of payment issues. The additional capacity generated by this trend has, supported by other effects such as Saudi Arabia＇s decision to maintain current production, triggered a significant reduction ofoil prices. Consequently, it is now oil exporters that struggle with the balance of payment issues and often these countries base their fiscal budget completely on fossil fuel revenues. In fact, these unconventional resources help turn the tide while oil exporters are now politically significantly weakened due to the increased energy sufficiency of the West. The catch is that the extraction of unconventional types ofoil has many environmental implications. So, internalising the environ- mental externalities have to be considered. This paper, therefore, assesses, next to geopolitics and geo-economics, the environmental implications of this trend.

关键词： energy security climatic change geo-economics geopolitics unconventional resources macroeconomics

An alternative approach to improve the compatibility of PCE in cement paste blend with coal gangue powder

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Waste Disposal and Sustainable Energy 2024年第1期6卷 139-150页

作者： Zonglin Xie Yuxuan Li Dahui Sun Yi Tian Jinyuan Hu Qiang Yuan Zheng Chen School of Civil Engineering Central South UniversityChangshaChina China Railway NO.9 Group CO. LTDShenyangChina National Engineering Research Center for High-Speed Railway Construction Technology ChangshaChina Guangxi Key Laboratory of Disaster Prevention and Engineering Safety Guangxi UniversityNanningChina

Coal gangue(CG)is an environmental waste that faces an urgent demand for disposal in *** utilization of CG in construction materials has broad application prospects and gained increasing ***,the poor compatibility of polycarboxylate superplasticizer(PCE)with CG powder hinders its efficiency in a wide range of ***,this paper attempts to improve the compatibility of PCE with CG powder in cement paste based on the regulation of aggregation and the adsorption behavior of *** light scattering(DLS)and fluorescence spectroscopy tests were carried out to understand the improved *** results indicated that the addition of CG powder increases the ionic strengths of the cement liquid phase,which makes PCE tend to aggregate at a lower concentration compared with no CG powder ***(CH_(3)COO)_(2)Cu is beneficial for enhancing the workability of cement paste by reducing PCE aggregation while maintaining the compressive strength of cement ***,(CH_(3)COO)_(2)Cu extra addition can be regarded as an effective and sustainable way to improve the workability of cement paste with CG powder.

关键词： Coal gangue powder Polycarboxylate superplasticizer Compatibility Aggregation

巴尔哲锆-铌-铍-稀土矿床成矿精细过程研究

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岩石学报 2024年第6期40卷 1817-1836页

作者：吴鸣谦马甲栋邓军刁习裴磊邱昆峰中国地质大学(北京)地球科学与资源学院北京100083 加拿大温莎大学环境学院温莎N9B 3P4 中国地质大学地质过程与矿产资源国家重点实验室北京100083 中国地质大学(北京)深时数字地球前沿科学中心北京100083

巴尔哲碱性花岗岩型关键金属矿床拥有世界级Zr、Nb、Be、REE资源量,其成矿具有多期次、多阶段特征。Zr矿化(Ⅰ阶段)发生在岩浆期,表现为多锆相(agpaitic)界熔花岗岩熔体结晶出原生钠锆硅酸盐(斜钠锆石),在该阶段,多锆相界熔花岗岩经历... 详细信息

巴尔哲碱性花岗岩型关键金属矿床拥有世界级Zr、Nb、Be、REE资源量,其成矿具有多期次、多阶段特征。Zr矿化(Ⅰ阶段)发生在岩浆期,表现为多锆相(agpaitic)界熔花岗岩熔体结晶出原生钠锆硅酸盐(斜钠锆石),在该阶段,多锆相界熔花岗岩经历钠质交代,斜钠锆石原位分解为锆石-石英假象,假象中锆石U-Pb年代学表明锆成矿发生在123.9±0.6Ma。随后,Nb-Be-REE矿化以多种矿物形式、分三个连续的阶段(Ⅱ、Ⅲ、Ⅳ阶段)、呈浸染状分布于遭受赤铁矿化的界熔花岗岩中,重稀土为主的矿物普遍形成于以轻稀土为主的矿物之前。Ⅱ阶段是巴尔哲矿床中Nb、Be和重稀土矿化的主要阶段,大部分界熔花岗岩均遭受了不同程度的赤铁矿化,并伴随钇兴安石、铈兴安石、钇易解石、铌铁矿等稀有稀土金属矿物的形成,主要形成以石英为主的假象(Nb-Be-REE假象),Nb-Be-REE假象的前体矿物并非某种Nb-Be-REE矿物。Ⅲ阶段主要形成黑稀金矿、独居石及氟碳铈矿,热液独居石U-Pb年代学指示该阶段热液成矿活动发生在122.8±0.6Ma。氟铈矿和氟碳钙铈矿部分交代氟碳铈矿构成了Ⅳ阶段的矿物组合。Nb、Be和REE在热液过程中的多阶段分配和富集,是造成巴尔哲矿床中复杂矿石矿物组合以及高品位Nb-Be-REE矿化的重要原因。Nb-Be-REE矿石矿物组合中不存在锆石,且其分布与雪球石英、钠质交代和锆石-石英假象的分布没有时空关联。此外,巴尔哲角闪石中Nb、Be、REE的含量低,表明原生锆硅酸盐矿物和角闪石不是Nb、Be和REE等关键金属的物质来源。结合各岩相中角闪石元素含量的变化与熔体包裹体成分特征,笔者提出Nb和REE的富集可能是氟化物-硅酸盐熔体不混溶耦合岩浆期后热液富集的结果。因此,巴尔哲矿床中需要开展精细的熔体/流体包裹体成分研究,针对关键金属尤其是Be的来源、熔-流体演化历程以及矿化精细过程开展更深入的研究。

关键词：巴尔哲碱性花岗岩关键金属岩浆-热液过程

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Tungsten Promoted Ni/Al_2O_3 Catalysts for Carbon Dioxide Reforming of Methane to Synthesis Gas

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Chemical Research in Chinese Universities 2004年第4期20卷 470-477页

作者： Thomas Suhartanto Andrew P. E. York Malcolm L. H. Green Wolfson Catalysis Centre Inorganic Chemistry Laboratory University of OxfordWolfson Catalysis Centre Inorganic Chemistry Laboratory University of OxfordWolfson Catalysis Centre Inorganic Chemistry Laboratory University of Oxford South Parks Road Oxford OX1 3QR UKSouth Parks Road Oxford OX1 3QR UKSouth Parks Road Oxford OX1 3QR UK

A series of tungsten promoted alumina supported nickel catalysts has been prepared for the carbon dioxide reforming of methane to synthesis gas. The catalysts have been characterized by means of XRD, TEM, and Laser Raman spectroscopy. It is shown that the addition of tungsten to the nickel catalyst can stabilize the catalyst and increase the resistance to carbon deposition. Adding a suitable amount of tungsten can also increase the catalyst activity to be close to that of supported noble metal catalysts. The carburisation of the tungsten modified nickel catalyst decreases the catalyst activity at lower reaction temperatures(3K), but has no effect on the catalyst performance at higher reaction temperatures. The alumina supported nickel catalyst modified by 0.67%(mass fraction) WO_3 has the equivalent equilibrium constant of the dry reforming reaction to that of alumina supported 5%(mass fraction) Ru at 873 K, and also has a lower activation energy for dry reforming than the latter.

关键词： Nickel catalyst Tungsten modifier CO_2 reforming Methane Syngas

Methodology of Single Crystal Growth and Microstructure Analysis of CoTi(Zr) Intermetallic Compounds

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Journal of Materials Science & Technology 2005年第6期21卷 817-821页

作者： Mike L.JENKINS Glyn TAYLOR Department of Materials University of Oxford Parks Road Oxford OX1 3PH UK

The effects of preparation and crystal growth methods on the microstructure, composition, and oxidation of CoTi（Zr） intermetallics were dealt with . A group of methods has been used to produce CoTi and CoTi（Zr） crystals to prevent the formation of titanium oxide particles during melting and crystal growth. The results show that more oxides formed when using powdered starting materials even though the metals handled were and melted under an inert gas atmosphere; using bulk starting materials produced alloys showed less oxidation than powders, but adding a small amount of AI to getter the oxygen was not sufficient to prevent TiO2 formation. However, using a slightly reducing atmosphere during initial melting was highly effective in reducing the formation of oxide. Crystal growth carried out in Ar did not reduce the amount of oxide but only redistributed the particles. TiO2 particles were found only in the grain boundaries after crystal growing, where they obstructed grain growth. Crystal growth in a vacuum was found to be essential in producing oxide free crystals. A seed selection technique was developed and used in growing CoTi single crystals. The microstructures of the samples were determined using optical microscopy, scanning electron microscopy and transmission electron microscopy, including the morphologies, grain sizes, oxide distributions and crystal structure confirmation.

关键词： CoTi CoTi(Zr) Intermetallics Crystal growth Nicrostructure

Application of microdialysis in tissue engineering monitoring

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Progress in Natural Science:Materials International 2008年第5期18卷 503-511页

作者： Zhaohui Li, Zhanfeng Cui Department of Engineering Science, oxford University, oxford ox1 3PJ, UK Department of Engineering Science Oxford University Oxford OX1 3PJ UK

In this review article, the microdialysis for tissue engineering monitoring is discussed. Among various monitoring techniques, micro- dialysis is advantageous for its capacity of perfusion on-line, and o -line multiple parameter monitoring. Following a description on the general system and performance, the main challenges to apply this technique for reliable long term monitoring are outlined. Further opportunities are identi ed.

关键词： Microdialysis Tissue culture monitoring Tissue engineering

MEASURING AND LOCATING ZONES OF CHAOS AND IRREGULARITY

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Journal of Systems Science & Complexity 2014年第3期27卷 494-506页

作者： GARNER David Matthew LING Bingo Wing-Kuen Department of Biological and Medical Sciences Oxford Brookes UniversityHeadington CampusGipsy LaneOxford OX3 0BPUnited Kingdom University of Lincoln Brayford PoolLincolnLN6 7TSUnited Kingdom

The new measures computed here are the spectral detrended fluctuation analysis(sDFA)and spectral multi-taper method(sMTM).sDFA applies the standard detrended fluctuation analysis(DFA) algorithm to power *** exploits the minute increases in the broadband response,typical of chaotic spectra approaching optimal *** authors chose the Brusselator,Lorenz,and Duffing as the proposed models to measure and locate chaos and severe *** series of chaotic parametric responses in short time-series is *** cycles have only a limited number of slow oscillations such as for systems biology and *** is difficult to create,locate,or monitor *** 50 linearly increasing starting points applied to the chaos target function(CTF);the mean percentage increases in Kolmogorov-Sinai entropy(KS-Entropy) for the proposed chosen models;and p-values when the models were compared statistically by Kruskal-Wallis and ANOVA1 test with distributions assumed normal are Duffing(CTF:31%:p 3);Lorenz(CTF:2%:p 3),and Brusselator(CTF:8%:p <0.01).Principal component analysis(PCA) is applied to assess the significance of the objective functions for tuning the chaotic *** PCA the conclusion is that CTF is the most beneficial objective function overall delivering the highest increases in mean KS-Entropy.

关键词：混沌性不规则性定位主成分分析测量目标函数柯尔莫哥洛夫波动分析