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Functional Inferences of Environmental Coccolithovirus Biodiversity

Virologica Sinica 2013年第5期28卷 291-302页

作者： jozef I Nissimov Mark jones johnathan A Napier Colin B Munn Susan A Kimmance michael j allen Plymouth Marine Laboratory Prospect Place University of Nottingham School of BiosciencesSutton Bonington Campus Department of Biological Chemistry Rothamsted Research School of Marine Science & Engineering Plymouth University

The cosmopolitan calcifying alga Emiliania huxleyi is one of the most abundant bloom forming coccolithophore species in the oceans and plays an important role in global biogeochemical cycling. Coccolithoviruses are a major cause of coccolithophore bloom termination and have been studied in laboratory, mesocosm and open ocean studies. However, little is known about the dynamic interactions between the host and its viruses, and less is known about the natural diversity and role of functionally important genes within natural coccolithovirus communities. Here, we investigate the temporal and spatial distribution of coccolithoviruses by the use of molecular fingerprinting techniques PCR, DGGE and genomie sequencing. The natural biodiversity of the virus genes encoding the major capsid protein （MCP） and serine palmitoyltransferase （SPT） were analysed in samples obtained from the Atlantic Meridional Transect （AMT）, the North Sea and the L4 site in the Westem Channel Observatory. We discovered nine new coccolithovirus genotypes across the AMT and L4 site, with the majority of MCP sequences observed at the deep chlorophyll maximum layer of the sampled sites on the transect. We also found four new SPT gene variations in the North Sea and at L4. Their translated fragments and the full protein sequence of SPT from laboratory strains EhV-86 and EhV-99B 1 were modelled and revealed that the theoretical fold differs among strains. Variation identified in the structural distance between the two domains of the SPT protein may have an impact on the catalytic capabilities of its active site. In summary, the combined use of ＇standard＇ markers （i.e. MCP）, in combination with metabolically relevant markers （i.e. SPT） are useful in the study of the phylogeny and functional biodiversity of coccolithoviruses, and can provide an interesting intracellular insight into the evolution of these viruses and their ability to infect and replicate within their algal hosts.

关键词： Coccolithovirus Major capsid protein Serine palmitoyltransferase Functional biodiversity

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阳离子型抗菌剂聚六亚甲基双胍与核酸结合的协同作用

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中国皮革 2011年第17期40卷 45-51页

作者： michael j. allen Andrew P. Morby Graham F. White 江正武(译) 赵春霞(译) 刘白玲(校) Cardiff School of Biosciences Cardiff University Cardiff CFIO 3US UK 中国科学院研究生院北京100039 中国科学院成都有机化学研究所四川成都610041

研究了广谱抗菌剂聚六亚甲基双胍(PHMB)与各类核酸的相互作用。通过滴定反应研究了PHMB与具有100个碱基(对)的单(双)链DNA、混合长度的标准DNA、tRNA相互作用形成的复合物沉淀。试验发现:PHMB与核酸之间是核苷酸/双胍基团以单元比相结... 详细信息

研究了广谱抗菌剂聚六亚甲基双胍(PHMB)与各类核酸的相互作用。通过滴定反应研究了PHMB与具有100个碱基(对)的单(双)链DNA、混合长度的标准DNA、tRNA相互作用形成的复合物沉淀。试验发现:PHMB与核酸之间是核苷酸/双胍基团以单元比相结合的。它们之间的这种结合具有很强的协同性,其表观Hill系数为10.3～14.6。用核酸滴定PHMB的荧光衍生物时,四类核酸的作用都显示了很强的荧光偏振强度,表明了核酸与PHMB之间的结合作用。PHMB与各类核酸之间强烈而广泛的结合作用,对这类抗菌剂的作用机理有着重要意义。

关键词：抗菌剂聚六亚甲基双胍阳离子表面活性剂 DNA结合协同性

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Linking water and nutrients through the vadose zone: a fungal interface between the soil and plant systems

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journal of Arid Land 2011年第3期3卷 155-163页

作者： michael F allen Center for Conservation Biology University of California

Plant water availability, use, and management have largely focused on physical processes of infiltration and the role of roots in uptake and transpiration. However, roots and mycorrhizal fungi redistribute water in complex patterns. Here I describe some of our observations and experiments showing that mycorrhizal fungi play key roles in moving water for both transpiration and to facilitate nutrient acquisition under dry conditions. Mycorrhizal fungal hyphae grow from both surface and deep roots even into bedrock to help extract water under dry conditions. In both deep and surface roots, mycorrhizal fungi acquire water from pores too small for roots and root hairs to access, and at distances from roots and root hairs. Mycorrhizal fungi are also able to utilize hydraulic-lifted water from plants to obtain nutrients in extremely dry surface soils. The importance of these root symbionts in water and nutrient dynamics, and as integrators of surface and deeper water dynamics need further investigation.

关键词： mycorrhiza vadose zone hydraulic redistribution drought

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Approximate ballistics formulas for spherical pellets in free flight

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Defence Technology（防务技术） 2018年第1期14卷 1-11页

作者： E.j.allen Department of Mathematics and Statistics Texas Tech University

The ballistics equations for spherical pellets in free flight are simplified through appropriate scaling of the pellet velocity and pellet distance. Two different drag coefficient curves are averaged to yield a single curve applicable to shot pellets and round balls. The resulting S-shaped drag coefficient curve is approximated by three straight-line segments. The scaled ballistics equations are then solved exactly and simple formulas are found for the velocity and flight time with respect to trajectory distance. The formulas are applicable to spherical shot pellets and round balls of any composition under any atmospheric conditions. The formulas are amenable to quick and easy computation and may also serve as an aid in understanding and comparing black-box ballistics calculators. For shotshell ballistics, an important assumption in the present investigation is that the pellets are moving as single, free spheres and not as a dense cloud or in a shot column, in particular, the pellets are not interacting during flight. Therefore, the formulas are most appropriate for single round balls, for large shot sizes, and for pellets of small shot size fired from open chokes. The formulas are clear and accessible, and can be implemented by military or law enforcement personnel as well as hunters and shooters. This work differs from previous investigations in that accurate ballistics formulas are derived for spherical projectiles of shotguns and muzzleloaders using realistic drag coefficients.

关键词： Ballistics Sphere Drag Shotgun Muzzleloader Nondimensionalization

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A RECONSIDERATION OF THE ACCURACY OF THE REISNER CATEGORISATION SYSTEM OF EGYPTIAN WATERCRAFT HULL TYPES Ⅵ–Ⅷ

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journal of Ancient Civilizations 2019年第1期34卷 1-19,125页

作者： michael allen Stephens Monash University

In 2012,I proposed an expansion of the accepted range of hull types utilized by the Egyptians during the Old and Middle Kingdoms,a range based initially on the models and surviving hulls published by Reisner.1 This series expansion ceased at Type V,as Type VI were“Solar”and VII“Divine”vessels,while Type VIII was known only from the New *** V,identifiable as the Manedjet(mand.t),the Day Boat,was included in this expansion due to the discovery and re-assembly of the Old Kingdom vessel of this type,found buried alongside the Great Pyramid,suggestive of its having been a functioning craft,and not *** the hull types Reisner had not categorized,being known only from iconographic depictions,I allocated temporary typological labels–ETH,an abbreviation for“Expedient Type Hull,”with a category and/or a sub category number or *** both the Reisner and the ETH forms,sub categories were developed,utilizing variations of such features as bow and stern finials or variations in hull shape,within the context of their category.

关键词： utilizing expansion abbreviation

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A plant-based diet and heart failure： case report and literature review

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journal of Geriatric Cardiology 2017年第5期14卷 375-378页

作者： Evan Y Choi Kathleen allen michael McDonnough Daniele Massera Robert j Ostfeld Department of Medicine Montefiore Medical Center Bronx NY USA Department of Nutrition & Food Studies New York University NY NY USA Department of Nutrition New York-Presbyterian Hospital NY NY USA Division of Cardiology Montefiore Medical Center Bronx NY USA

Heart failure is associated with high rates of morbidityand mortality, and is a burden to the healthcare *** is a growing appreciation for the role diet may play inthe development and treatment of heart failure.

关键词： Heart failure Lifestyle Plant-based diet Vegetarian

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The supernova remnant CTB 37B and its associated magnetar CXOU j171405.7-381031:evidence for a magnetar-driven remnant

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Research in Astronomy and Astrophysics 2011年第6期11卷 625-630页

作者： j.E.Horvath M.P.allen Instituto de Astronomia Geofísica e Ciências Atmosféricas-Universidade de So PauloRua do Mato122605508-900 Cidade Universitria So Paulo SPBrazil CEFET So Paulo Rua Pedro Vicente 62501109-010Caninde'So Paulo SPBrazil

We discuss the association between the candidate magnetar CXOU j171405.7-381031 and the supernova remnant CTB *** recent detection of the period derivative of the object allowed an estimation of a young characteristic age of only ～ *** value is too small to be compatible even with the minimum radius of the remnant being ≥ 10 pc,the value corresponding to the lower limit of the estimated distance of 10.2 ± 3.5 kpc,unless the true distance happens to be even smaller than the lower *** argue that a consistent scenario for the remnant＇s origin,in which the latter is powered by the energy injected by a young magnetar,is indeed more accurate to explain the young age,and demonstrates its non-standard（***-driven） nature.

关键词： stars:supernova — stars:neutron

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Relationships between regulated DBPs and emerging DBPs of health concern in U.S. drinking water

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journal of Environmental Sciences 2022年第7期34卷 161-172页

作者： Stuart W.Krasner Ai jia Chih-Fen T.Lee Raha Shirkhani joshua M.allen Susan D.Richardson michael j.Plewa Metropolitan Water District of Southern California Water Quality LaboratoryCA 91750USA Department of Chemistry and Biochemistry University of South CarolinaSC 29208USA Department of Crop Sciences University of Illinois at Urbana-ChampaignIL 61801USA Safe Global Water Institute University of Illinois at Urbana-ChampaignIL 61801USA

A survey was conducted at eight U.S. drinking water plants, that spanned a wide range of water qualities and treatment/disinfection practices. Plants that treated heavily-wastewaterimpacted source waters had lower trihalomethane to dihaloacetonitrile ratios due to the presence of more organic nitrogen and HAN precursors. As the bromide to total organic carbon ratio increased, there was more bromine incorporation into DBPs. This has been shown in other studies for THMs and selected emerging DBPs(HANs), whereas this study examined bromine incorporation for a wider group of emerging DBPs(haloacetaldehydes, halonitromethanes). Moreover, bromine incorporation into the emerging DBPs was, in general, similar to that of the THMs. Epidemiology studies that show an association between adverse health effects and brominated THMs may be due to the formation of brominated emerging DBPs of heath concern. Plants with higher free chlorine contact times before ammonia addition to form chloramines had less iodinated DBP formation in chloraminated distribution systems, where there was more oxidation of the iodide to iodate(a sink for the iodide) by the chlorine. This has been shown in many bench-scale studies(primarily for iodinated THMs), but seldom in full-scale studies(where this study also showed the impact on total organic iodine. Collectively, the THMs, haloacetic acids, and emerging DBPs accounted for a significant portion of the TOCl, TOBr, and TOI;however, ~50% of the TOCl and TOBr is still unknown. The correlation of the sum of detected DBPs with the TOCl and TOBr suggests that they can be used as reliable surrogates.

关键词： Disinfection by-products Total organic bromine Total organic iodine Trihalomethanes Haloacetonitriles Haloacetaldehydes Iodo-trihalomethanes Iodoacetic acids

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Coordination chemistry of surface-associated ligands for solid-liquid adsorption of rare-earth elements

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journal of Rare Earths 2023年第1期41卷 1-18页

作者： jessica L.Hovey Timothy M.Dittrich Matthew j.allen Department of Chemistry Wayne State University5101 Cass AvenueDetroitMI48202USA Department of Civil and Environmental Engineering 5050 Anthony Wayne DriveWayne State UniversityDetroitMIl48202USA

General guidelines for the design of ligands for the enrichment of rare-earth elements by solid-liquid adsorption are described using coordination *** properties of ligands include selectivity of metal ions based on adjustment of donor atom polarizability,denticity,and the pKarange of the binding *** selectivity of solid-phase materials for the enrichment of rare-earth ions by the ligand design guidelines is outlined,with special consideration of additional variable factors including steric hindrance,saturated binding sites,variability in speciation caused by the identity of counterions and ionic strength,and size-exclusivity in ligands stemming from differences in bite angle,preo rganization of ligands,or intraligand *** review analyzes some principles of selectivity of rare-earth elements with ligands organized by donor type from examples collected from reports published between 2009 and 2021.

关键词： Chelating ligand Coordination chemistry Solid-phase material Rare-earth element Separation Solid-liquid extraction

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Pico-washing:simultaneous liquid addition and removal for continuous-flow washing of microdroplets

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Microsystems & Nanoengineering 2022年第2期8卷 249-261页

作者： michael j.Siedlik David Issadore Department of Bioengineering University of PennsylvaniaPhiladelphiaPA 19104United States

Droplet microfluidics is based on a toolbox of several established unit operations,including droplet generation,incubation,mixing,pico-injection,and *** the last two decades,the development of droplet microfluidic systems,which incorporate these multiple unit operations into a workflow,has demonstrated unique capabilities in fields ranging from single-cell transcriptomic analyses to materials *** unit operation that is sorely underdeveloped in droplet microfluidics is washing,exchange of the fluid in a droplet with a different ***,we demonstrate what we name the"pico-washer,"a unit operation capable of simultaneously adding fluid to and removing fluid from droplets in flow while requiring only a small footprint on a microfluidic *** describe the fabrication strategy,device architecture,and process parameters required for stable operation of this technology,which is capable of operating with kHz droplet ***,we provide an image processing workflow to characterize the washing process with microsecond and micrometer ***,we demonstrate the potential for integrated droplet workflows by arranging two of these unit operations in series with a droplet generator,describe a design rule for stable operation of the pico-washer when integrated into a system,and validate this design rule *** anticipate that this technology will contribute to continued development of the droplet microfluidics toolbox and the realization of novel droplet-based,multistep biological and chemical assays.

关键词： operations simultaneous removing

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