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Arsenobetaine and thio-arsenic species in marine macroalgae and herbivorous animals: Accumulated through trophic transfer or produced in situ?

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j.urnal of Environmental Sciences 2016年第11期28卷 131-139页

作者： simon foster William Maher Ecochemistry Laboratory Institute for Applied Ecology University of Canberra

Arsenobetaine（AB） and thio-arsenoribosides were measured in common macroalgae species（8 phaeophyta, 4 rhodophyta and 2 chlorphyta）, along the Australian south east coast line. As well, arsenic species profiles were measured for two common marine herbivores, the sea urchin Centrostephanus rodgersii and the fish Odax cyanomelas that graze on these macroalgae to understand if trophic transfer of these species would account for their presence in marine herbivores. AB was found in seven of the fourteen macroalgae species investigated but does not contributed significantly to any of the macroalgae arsenic content（0.01-1.2 μg/g）. AB was found in only two of the brown macroalgae and all the red and green macroalgae（with the exception of Corallina officinalis）. Thio-arsenic species were found sporadically, but not in high concentrations in any of the macroalgae *** present in macroalgae is likely to be associated with epiphytic organisms while thio-arsenoribosides are likely to be produced by decaying parts of damaged macroalgae.A laboratory feeding experiment in which the herbivorous gastropod, Austrocochlea constricta, was fed macroalgae containing thio-arsenoribosides for a 24 hr period every three days showed that these are readily accumulated over a short period. Thio-arsenoribosides in herbivores are therefore probably obtained through trophic transfer. Some AB is also obtained through trophic transfer; however, the presence of trimethylated arsonioribosides,a hypothesized precursor of AB formation in herbivores, suggests that some AB is produced within herbivores from the transformation of arsenoribosides accumulated from their diet.

关键词： Arsenobetaine Arsenic Metabolism Thio-arsenosugars Macroalgae Gastropods

Evaluation of the ability of arsenic species to traverse cell membranes by simple diffusion using octanol-water and liposome-water partition coefficients

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j.urnal of Environmental Sciences 2016年第11期28卷 222-232页

作者： Teresa Chavez-Capilla William Maher Tamsin Kelly simon foster Ecochemistry Laboratory Institute for Applied Ecology University of Canberra Canberra ACT 2601 Australia National Centre for Forensic Studies Faculty of Education Science Technology and Mathematics University of Canberra CanberraACT 2601 Australia

Arsenic metabolism in living organisms is dependent on the ability of different arsenic species to traverse biological membranes. Simple diffusion provides an alternative influx and efflux route to mediated transport mechanisms that can increase the amount of arsenic available for metabolism in cells. Using octanol-water and liposome-water partition coefficients, the ability of arsenous acid, arsenate, methylarsonate, dimethylarsinate, thio-methylarsonate, thiodimethylarsinic acid, arsenotriglutathione and monomethylarsonic diglutathione to diffuse through the lipid bilayer of cell membranes was investigated. Molecular modelling of arsenic species was used to explain the results. All arsenic species with the exception of arsenate, methylarsonate and thio-methylarsonate were able to diffuse through the lipid bilayer of liposomes, with liposome-water partition coefficients between 0.04 and 0.13. Trivalent arsenic species and thio-pentavalent arsenic species showed higher partition coefficients, suggesting that they can easily traverse cell membranes by passive simple diffusion. Given the higher toxicity of these species compared to oxo-pentavalent arsenic species, this study provides evidence supporting the risk associated with human exposure to trivalent and thio-arsenic species.

关键词： ArsenicLiposomesPartition coefficientsPassive simple diffusionTrivalent arsenic speciesThio-arsenic species

Analysis of Longitudinal Profiles along the Eastern Margin of the Qinghai-Tibetan Plateau

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j.urnal of Mountain Science 2013年第4期10卷 643-657页

作者： simon j. Aiken Gary j. Brierley School of Environment the University of AucklandAuckland 1010 New Zealand

Resulting from the collision of the Eurasian and Indian plates, the Qinghai-Tibetan Plateau is commonly known as the ＇roof of the world＇. Collectively the Yarlung Tsangpo, Nu, Laneang, Yangtze, Yalong, and Yellow River basins drain the eastern margin of the plateau. In this paper, we utilize Shuttle Radar Topography Mission elevation data to examine morphometric and relief attributes of these basins to reveal insights rates of incision. A robust into tectonic activity and technique using Maflab is proposed to alleviate errors associated with SRTM data in the derivation of river longitudinal profiles. Convex longitudinal profiles are interpreted to be a product of uplift rates that exceed rates of channel incision along the entire margin of the Qinghai- Tibetan Plateau. Highest relief towards the south reflects extensive fluvial incision. High relief is also prominent along maj.r active faults. Erosion patterns are related to distance from knickpoints. Highest rates of erosion and incision are evident towards the south, with decreasing values towards the north, suggesting a link between tectonic activity and erosion.

关键词： Longitudinal profile Erosion Relief Tectonics Qinghai-Tibetan Plateau

Identification of Differentially Senescing Mutants of Wheat and Impacts on Yield,Biomass and Nitrogen Partitioning

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j.urnal of Integrative Plant Biology 2012年第8期54卷 555-566页

作者： Adinda P.Derkx simon Orford simon Griffiths M.j.hn Foulkes Malcolm j. Hawkesford Plant Biology and Crop Science Department Rothamsted ResearchHarpendenHertfordshireAL5 2JQUK Division of Plant&Crop Sciences School of BiosciencesUniversity of NottinghamSutton Bonington CampusNr LoughboroughLE12 5RDUK j.hn Innes Centre Norwich Research ParkColneyNorwich NR4 7UHUK

Increasing photosynthetic capacity by extending canopy longevity during grain filling using slow senescing stay-green genotypes is a possible means to improve yield in wheat. Ethyl methanesulfonate （EMS） mutated wheat lines （Triticum aestivum L. cv. Paragon） were screened for fast and slow canopy senescence to investigate the impact on yield and nitrogen partitioning. Stay-green and fast-senescing lines with similar anthesis dates were characterised in detail. Delayed senescence was only apparent at higher nitrogen supply with low nitrogen supply enhancing the rate of senescence in all lines. In the stay-green line 3 （SG3）, on a whole plant basis, tiller and seed number increased whilst thousand grain weight （TGW） decreased; although a greater N uptake was observed in the main tiller, yield was not affected. In fast-senescing line 2 （FS2）, yield decreased, principally as a result of decreased TGW. Analysis of N-partitioning in the main stem indicated that although the slow-senescing line had lower biomass and consequently less nitrogen in all plant parts, the proportion of biomass and nitrogen in the flag leaf was greater at anthesis compared to the other lines; this contributed to the grain N and yield of the slow-senescing line at maturity in both the main tiller and in the whole plant. A field trial confirmed senescence patterns of the two lines, and the negative impact on yield for FS2 and a positive impact for SG3 at low N only. The lack of increased yield in the slow-senescing line was likely due to decreased biomass and additionally a possible sink limitation.

关键词： Wheat senescence stay-green grain-filling yield nitrogen.

In situ characterization of particle formation in spray flame synthesis using wide-angle light scattering

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Particuology 2024年第3期86卷 304-312页

作者： simon Aβmann Franz j.T.Huber Stefan Will Lehrstuhl für Technische Thermodynamik(LTT) Friedrich-Alexander-Universitat Erlangen-Nürnberg(FAU)Erlangen91058Germany Erlangen Graduate Schoolin Advanced Optical Technologies(SAOT) Friedrich-Alexander-Universitat Erlangen-Nurnberg(FAU)Erlangen91052Germany Competence Unit Engineering of Advanced Materials(EAM) Friedrich-Alexander-Universitat Erlangen-Nürnberg(FAU)Erlangen91052Germany

Wide-angle light scattering(WALS)was used for in situ measurements of droplet and nanoparticle size distributions during the synthesis of titania and iron oxide particles from liquid precursor solutions in the standardized SpraySyn burner for spray flame *** was synthesized from titanium tetraisopropoxide(TTIP)and iron oxide from iron(II)nitrate nonahydrate(INN)using ethanol(EtOH)as *** images were taken at heights up to 120 mm above the burner surface and classified into droplet and particle *** size distributions were derived from a sequential analysis of scattering data containing the oscillating Mie pattern,the lognormal size distribution parameters for spherical and fractal particle fractions from a multivariate approach on averaged particle scattering *** results show that the precursor addition leads to altered evaporation behavior and even droplet disruption probably induced by puffing or micro-explosions compared to pure *** the case of TTIP(a hygroscopic alkoxide),the synthesis of a large fraction of spheres was observed,while the nitrate INN leads to the formation of mostly fractal aggregates.

关键词： Spray flame synthesis Metal oxide particles Elastic light scattering Droplet size distribution Nanoparticle morphology Particle size distribution

Oil-bearing fluid inclusions from the Palaeoproterozoic:A review of biogeochemical results from time-capsules >2.0 Ga old

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Science China Earth Sciences 2009年第1期52卷 1-11页

作者： simon C. GEORGE Adriana DUTKIEWICZ Herbert VOLK j.hn RIDLEY David j. MOSSMAN Roger BUICK Department of Earth and Planetary Sciences Macquarie University School of Geosciences University of Sydney CSIRO Petroleum Department of Geosciences Colorado State University Department of Geography Mount Allison University Department of Earth and Space Sciences & Astrobiology Program University of Washington

The observation of oil inclusions trapped prior to 2.0 Ga in Palaeoproterozoic rocks and the ability to obtain detailed molecular geochemical information from them provide a robust way for understanding the early biog... 详细信息

关键词： Palaeoproterozoic fluid inclusion oil biomarker blank

Tesco Strikes Out into Asia

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Frontiers of Business Research in China 2013年第2期7卷 289-310页

作者： M j.foster Toj.Noh Kingston Business School Kingston Upon Thames KT2 7LB UK Department of Management Kumoh National Institute of Technology Gyongbuk 730-701Korea

The case looks at the internationalisation of Tesco PLC, a successful UK retailing business, and in particular how and why it has gone about developing its business in Southeast/East Asia. The case is suitable for use with final year undergraduate and especially postgraduate students, in either corporate strategy or international business modules. The case follows Tesco＇s moves into Thailand, South Korea, and most recently China. It is found that the methods of entry to the new markets/countries and strategies used post-entry have varied country by country, culture by culture. The strategies adopted are found not to have been universally successful, which raises questions as to why that may be. It is expected that students will be able to identify the entry methods and reasons for their use; determine the business strategies adopted country by country, explore why they may differ, and locate the influences of the varying cultures. They will be expected to assess how successful Tesco has been in these processes. Finally, they should explore the question whether the giant China market can indeed be ＂an ultimate prize＂ and if so how it should best be tackled. For the time being, South Korea is arguably the most successful part of the company＇s Asian push.

关键词： retailing internationalisation FDI j.int venture (j.) businessstrategies East Asia China

Structural Basis of Interaction of Bipartite Nuclear Localization Signal from Agrobacterium VirD2 with Rice Importin-o

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Molecular Plant 2014年第6期7卷 1061-1064页

作者： Chiung-Wen Chang, simon j. Williams, Rafael Miguez Cou?ago Bostj.n Kobe School of Chemistry and Molecular Biosciences Institute for Molecular Bioscience and Australian Infectious Diseases ResearchCentre University of Queensland Brisbane Qld 4072 Australia

Dear Editor, In the eukaryotic cell, the nuclear envelope separates genomic DNA from the rest of the cell, but ensures a molecu- lar communication between the nucleus and the cytoplasm through the nuclear pore complexes （NPCs）. Nuclear trans- port of macromolecules is an energy-dependent process, exemplified by the classical nuclear import pathway. In the cytoplasm, proteins containing classical nuclear localization signals （cNLSs） are recognized by a hetero-dimeric transport receptor （importin-α （Impα）：importin-β （Impl3） complex）. Impa is employed as an adaptor protein that specifically rec-ognizes the classical nuclear localization signal （cNLS） from the cargo protein （Marfori et al., 2011）. Translocation of the trimeric cargo：transport receptor import complex through the NPCs is mediated by transient interactions between Impβ and nucleoporins in the NPC. The directionality of the trans- port is imparted by the asymmetric distribution, between the cytoplasm and the nucleus, of the distinct nucleotide-bound （GTP/GDP） states of the small GTPase Ran （Tran et al., 2007）.

关键词： AGROBACTERIUM RESEARCH PLANT proteins PLANT proteins -- Structure PLANT cell nuclei CRYSTAL structure CARRIER proteins -- Molecular structure CARRIER proteins RICE -- Research

Kingfisher Attacks the China Market

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Frontiers of Business Research in China 2012年第1期6卷 156-168页

作者： M j.foster C S Tseng Kingston Business School Kingston Upon Thames KT2 7LB UK Department of Marketing City University of Hong Kong Hong Kong China

This article examines the entry to the Chinese market of Kingfisher plc under its B＆Q brand, operating in the DIY or home improvement market. It is a pedagogically oriented case in the international strategy area, which deals with both the mode of market development by the company in China and some of the softer issues arising from that process relating to HR in the company and the inevitable cultural challenges it faced. The story begins in the mid-1990s and goes through to the early summer of 2010. On the one hand, the entry has been successful： B＆Q is now a significant presence in China, holding number one position in their chosen market, which is primarily highly fragmented; there is some concentration in four key cities in the wealthy east coast region; and it has made profits over a fair portion over the last decade. Lessons were learned from the initial mistakes and the core sales proposition in China has been crafted to differ from that in the original UK home base. However, for the last three completed financial years, losses have been booked and significant changes have been made or were planned at the time of writing. Some changes were inevitable, but which were they （other than those where the Chinese government changed its rules）？

关键词： Multinational Corporation (MNC) retailing do-it-yourself (DIY) China regulation market development