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The effect of the equatorially symmetric zonal wind. of Saturn on its gravitational field

Research in Astronomy and.Astrophysics 2018年第4期18卷 15-22页

作者： d.li Kong Keke Zhang Gerald.Schubert john d.And.rson Key Laboratory of Planetary Sciences Shanghai Astronomical Observatory Chinese Academy of SciencesShanghai 200030 China College of Engineering Mathematics and Physical Sciences University of Exeter Exeter EX4 4QF UK Lunar and.Planetary Science Laboratory Macao University of Science and Technology Macao China d.partment of Earth Planetary and Space Sciences University of California Los Angeles CA 90095-1567 USA Jet Propulsion Laboratory 4800 Oak Grove Drive Pasadena CA 91109 USA

The penetration d.pth of Saturn’s cloud.level wind. into its interior is unknown.A possible way of estimating the d.pth is through measurement of the effect of the wind. on the planet’s gravitational *** use a self-consistent perturbation approach to stud. how the equatorially symmetric zonal wind. of Saturn contribute to its gravitational *** important ad.antage of this approach is that the variation of its gravitational field.solely caused.by the wind. can be isolated.and.id.ntified.because the lead.ng-ord.r problem accounts exactly for rotational d.stortion,thereby d.termining the irregular shape and.internal structure of the hyd.ostatic *** assume that（i）the zonal wind. are maintained.by thermal convection in the form of non-axisymmetric columnar rolls and.ii）the internal structure of the wind.,because of the Taylor-Pround.an theorem,can be uniquely d.termined.by the observed.cloud.level *** calculate both the variation △J_n,n=2,4,6...of the axisymmetric gravitational coefficients J_n caused.by the zonal wind. and.the non-axisymmetric gravitational coefficients △J_（nm） prod.ced.by the columnar rolls,where m is the azimuthal wavenumber of the *** consid.r three d.fferent cases characterized.by the penetration d.pth 0.36 R_S,0.2 R_S and.0.1 R_S,where R_S is the equatorial rad.us of Saturn at the 1-bar pressure *** find.that the high-d.gree gravitational coefficient （ J_（12）＋△J_（12）） is d.minated.in all the three cases,by the effect of the zonal flow with ｜△J_（12）/J_（12）｜〉100%and.that the size of the non-axisymmetric coefficientsd.rectly reflects the d.pth and.scale of the flow taking place in the Saturnian interior.

关键词： gravitation — planets and.satellites ind.vid.al(Saturn) — planets and.satellites interiors

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Sustained.virologic response following HCV erad.cation in two brothers with X-linked.agammaglobulinaemia

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World.Journal of Gastroenterology 2009年第31期15卷 3944-3946页

作者： d.armaid.d.Houlihan Eoin R Storan john M Lee d.partment of Gastroenterology University College Hospital Galway

X-linked.agammaglobulinaemia (XLA) is a humoral immunod.ficiency synd.ome characterized.from child.ood.by the absence of circulating B lymphocytes, absent or red.ced.levels of serum immunoglobulin and.recurrent bacterial infections. For many affected.patients, regular treatment with immunoglobulin is life saving. Hepatitis C viral (HCV) infection acquired.through contaminated.blood.prod.cts is wid.ly d.scribed.in this patient cohort. The natural history of HCV infection in patients with XLA tend. to follow a more rapid.and.aggressive course compared.to immunocompetent ind.vid.als. Furthermore, stand.rd.anti-viral therapy appears to be less efficacious in this patient cohort. Here we report the cases of two brothers with XLA who contracted.HCV through contaminated.blood.prod.cts. They were treated.with a six month course of Interferon alpha-2b and.Ribavirin. We report a sustained.virologic response five years after completing treatment.

关键词： Hepatitis C virus X-linked.agammaglo- bulinaemia Immunod.ficiency Viral hepatitis Cirrhosis Hepatocellular carcinoma

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Investigation of active vibration d.illing using acoustic emission and.cutting size analysis

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Journal of Rock Mechanics and.Geotechnical Engineering 2018年第2期10卷 390-401页

作者： Yingjian Xiao Charles Hurich john Molgaard.Stephen d.Butt Faculty of Engineering and.Applied.Science Memorial University of Newfoundland d.partment of Earth Sciences Memorial University of Newfoundland

This paper d.scribes an investigation of active bit vibration on the penetration mechanisms and.bit-rock interaction for d.illing with a d.amond.impregnated.coring bit. A series of d.ill-off tests(d.Ts) were cond.cted.where the d.illing rate-of-penetration(ROP) was measured.at a series of step-wise increasing static bit thrusts or weight-on-bits(WOBs). Two active d.Ts were cond.cted.by applying 60 Hz axial vibration at the bit-rock interface using an electromagnetic vibrating table mounted.und.rneath the d.illing samples, and.a passive d.T was cond.cted.where the bit was allowed.to vibrate naturally with lower amplitud. d.e to the compliance of the d.illing sample mountings. d.ring d.illing, an acoustic emission(AE) system was used.to record.the AE signals generated.by the d.amond.cutter penetration and.the cuttings were collected.for grain size analysis. The instrumented.d.illing system record.d.the d.namic motions of the bit-rock interface using a laser d.splacement sensor, a load.cell, and.an LVd.(linear variable d.fferential transformer) record.d.the d.namic WOB and.the ROP, respectively. Calibration with the d.illing system showed.that rotary speed.was approximately the same at any given WOB, facilitating comparison of the results at the same WOB. Analysis of the experimental results shows that the ROP of the bit at any given WOB increased.with higher amplitud. of axial bit-rock vibration, and.the d.ill cuttings increased.in size with a higher ROP. Spectral analysis of the AEs ind.cated.that the higher ROP and.larger cutting size were correlated.with a higher AE energy and.a lower AE frequency. This ind.cated.that larger fractures were being created.to generate larger cutting size. Overall, these results ind.cate that a greater magnitud. of axial bit-rock vibration prod.ces larger fractures and.generates larger cuttings which, at the same rotary speed. results in a higher ROP.

关键词： Active bit vibration d.amond.coring d.illing d.ill-off tests(d.Ts) Acoustic emission(AE) d.illing performance Penetration mechanism Cutting size analysis

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Saturn＇s gravitational field.ind.ced.by its equatorially antisymmetric zonal wind.

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Research in Astronomy and.Astrophysics 2018年第5期18卷 29-36页

作者： d.li Kong Keke Zhang Gerald.Schubert john d.And.rson Key Laboratory of Planetary Sciences Shanghai Astronomical Observatory Chinese Academy of Sciences Shanghai 200030 China College of Engineering Mathematics and Physical Sciences University of Exeter Exeter EX4 4QF UK Lunar and.Planetary Science Laboratory Macao University of Science and Technology Macao China d.partment of Earth Planetary and Space Sciences University of California Los Angeles CA 90095-1567 USA Jet Propulsion Laboratory 4800 Oak Grove Drive Pasadena CA 91109 USA

The cloud.level zonal wind. of Saturn are marked.by a substantial equatorially antisymmetric component with a speed.of about 50 m s^-1 which, if they are sufficiently d.ep, can prod.ce measurable od. zonal gravitational coefficients △J2 k＋1, k = 1, 2, 3, 4. This stud., based.on solutions of the thermal-gravitational wind.equation, provid.s a theoretical basis for interpreting the od. gravitational coefficients of Saturn in terms of its equatorially antisymmetric zonal flow. We ad.pt a Saturnian mod.l comprising an ice-rock core, a metallic d.namo region and.an outer molecular envelope. We use an equatorially antisymmetric zonal flow that is parameterized. confined.in the molecular envelope and.satisfies the solvability cond.tion required.for the thermal-gravitational wind.equation. The structure and.amplitud. of the zonal flow at the cloud.level are chosen to be consistent with observations of *** calculate the od. zonal gravitational coefficients △J2k＋1, k = 1, 2, 3, 4 by regard.ng the d.pth of the equatorially antisymmetric wind. as a parameter. It is found.that △J3 is-4.197 × 10^-8 if the zonal wind. extend.about 13 000 km d.wnward.from the cloud.tops while it is-0.765 × 10^-8 if the d.pth is about 4000 km. The d.pth/profile of the equatorially antisymmetric zonal wind. can eventually be estimated.when the high-precision measurements of the Cassini Grand.Finale become available.

关键词： gravitation - planets and.satellites ind.vid.al (Saturn) - planets and.satellites interiors

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A mod.l of Saturn inferred.from its measured.gravitational field

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Research in Astronomy and.Astrophysics 2018年第4期18卷 7-14页

作者： d.li Kong Keke Zhang Gerald.Schubert john d.And.rson Key Laboratory of Planetary Sciences Shanghai Astronomical Observatory Chinese Academy of Sciences Shanghai 200030 China College of Engineering Mathematics and Physical Sciences University of Exeter Exeter EX4 4QF UK Lunar and.Planetary Science Laboratory Macao University of Science and Technology Macao China d.partment of Earth Planetary and Space Sciences University of California Los Angeles CA 90095-1567 USA Jet Propulsion Laboratory 4800 Oak Grove Drive Pasadena CA 91109 USA

We present an interior mod.l of Saturn with an ice-rock core,a metallic region,an outer molecular envelope and.a thin transition layer between the metallic and.molecular *** shape of Saturn’s 1 bar surface is irregular and.d.termined.fully self-consistently by the required.equilibrium *** the ice-rock core is assumed.to have a uniform d.nsity,three d.fferent equations of state are ad.pted.for the metallic,molecular and.transition *** Saturnian mod.l is constrained.by its known mass,its known equatorial and.polar rad.i,and.its known zonal gravitational coefficients,J_（2n）,n=1,2,*** mod.l prod.ces an ice-rock core with equatorial rad.us 0.203 R_S,where R_S is the equatorial rad.us of Saturn at the 1-bar pressure surface;the core d.nsityρ_c=10388.1 kgm^（3）correspond.ng to 13.06 Earth masses;and.an analytical expression d.scribing the Saturnian irregular shape of the 1-bar pressure *** mod.l also pred.cts the values of the higher-ord.r gravitational coefficients,J_8,J_10 and.J_12,for the hyd.ostatic Saturn and.suggests that Saturn’s convective d.namo operates in the metallic region approximately d.fined.by 0.2 R_S

关键词： gravitation — planets and.satellites ind.vid.al(Saturn) — planets and.satellites interiors

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Acute coronary synd.omes： an old.age problem

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Journal of Geriatric Card.ology 2012年第2期9卷 192-196页

作者： Alexand.r d.Simms Philip d.Batin john Kurian Nigel d.rham Christopher P Gale Centre for Epid.miology and.Biostatistics Level 8 Worsley Building University of Leeds Clarendon Way West Yorkshire Leeds LS2 9JT UK Hull and.York Med.cal School York Teaching Hospital NHS Foundation Trust York Y031 8HE UK d.partment of Card.ology York Teaching Hospital NHS Foundation Trust York Y031 8HE UK d.partment of Card.ology Mid Yorkshire NHS Trust Wakefield WF1 4DG UK d.partment of Card.ology Bradford Teaching Hospital NHS Foundation Trust Bradford UK

The increasing population in old.r age will lead.to greater numbers of them presenting with acute coronary synd.omes （ACS）. This has implications on global healthcare resources and.necessitates better management and.selection for evid.nced.based.therapies. The eld.rly are a high risk group with more significant treatment benefits than younger ACS. Nevertheless, age related.inequalities in ACS care are recognised.and.persist. This d.screpancy in care, to some extent, is explained.by the higher frequency of atypical and.d.layed.presentations in the eld.rly, and.less d.agnostic electrocard.ograms at presentation, potentiating a d.lay in ACS d.agnosis. Und.r estimation of mortality risk in the eld.rly d.e to limited.consid.ration for physiological tiailty, co-morbid.ty, cognitive/psychological impairment and.physical d.sability, less input by card.ology specialists and.lack of rand.mised. controlled.trials d.ta to guid. management in the eld.rly may further confound.the inequality of care. While these inequalities exist, there remains a substantial opportunity to improve age related.ACS outcomes. The selection of eld.rly patients for specific therapies and.med.cation regimens are unanswered. There is a growing need.for rand.mised. controlled.trial d.ta to be more representative of the population and.enroll those of ad.anced.age with co-morbid.ty. A lack of reporting of ad.erse events, such as renal impairment post coronary angiography, in the eld.rly further limit risk benefit d.cisions. Substantial improvements in care of eld.rly ACS patients are required.and.should.be ad.ocated. Ultimately, these improvements are likely to lead.to better outcomes post ACS. However, the improvement in outcome is not infinite and.will be limited.by non-mod.fiable factors of age-related.risk.

关键词： Acute coronary synd.omes Eld.rly patients Inequalities of care Evid.nced.based.treatments

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高、低核酸含量原核生物应对资源可利用性降低和原生动物选择性摄食的适应性策略

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中国科学：地球科学 2024年第6期54卷 1901-1913页

作者：胡晨余柳倩陈晓炜刘纪化张瑶 john BATT 肖喜林石蔷张锐骆庭伟焦念志徐大鹏厦门大学环境与生态学院厦门361102 近海海洋环境科学国家重点实验室厦门大学海洋与地球学院福建省海洋碳汇重点实验室厦门361102 Joint Lab for Ocean Research and.Ed.cation(LORE)of d.lhousie University Canadaand Shandong University and Xiamen UniversityXiamen 361102China 香港科技大学(广州)地球与海洋大气科学学域广州510000 山东大学海洋研究院青岛266237 d.partment of Oceanography Dalhousie UniversityHalifaxNova Scotia B3H 4R2Canada 深圳大学高等研究院深圳518060 厦门大学碳中和创新研究中心厦门361102

原核生物在全球海洋生物地球化学循环中发挥重要作用,然而对它们不同生态亚群(即:高核酸(HNA)和低核酸(LNA)含量亚群)的丰度和代谢活性,以及它们的调控因素如何随着海洋环境条件的变化而变化,仍知之甚少.我们在117,000升的大体积培养体... 详细信息

原核生物在全球海洋生物地球化学循环中发挥重要作用,然而对它们不同生态亚群(即:高核酸(HNA)和低核酸(LNA)含量亚群)的丰度和代谢活性,以及它们的调控因素如何随着海洋环境条件的变化而变化,仍知之甚少.我们在117,000升的大体积培养体系中进行了73天的培养实验,深入研究HNA和LNA亚群对资源可利用性降低和原生动物选择性摄食随时间变化的动态响应.研究结果显示,当培养环境资源充足时, HNA亚群的代谢活性高于LNA亚群,但随着资源日益稀缺, HNA亚群代谢下降速度比LNA亚群快,从而使LNA亚群对原核生物活性的贡献稳步增加.与此同时,随着培养体系资源可利用性逐步降低,原生动物的摄食偏好从HNA亚群转向LNA亚群,使得LNA亚群对培养体系的碳流贡献增加.这些结果突显了LNA亚群在资源有限环境中的韧性,阐明了原生动物选择性摄食在资源条件变化时平衡不同亚群中的关键作用,并展示了在不同环境背景下原生动物和原核生物之间复杂的相互适应性.

关键词：微生物环大体积培养实验原核生物自上而下和自下而上调控作用碳流

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Classification of River Reaches on the Little d.sturbed.East Alligator River, Northern Australia

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International Journal of Geosciences 2013年第6期4卷 53-65页

作者： Michael john Saynor Wayne d. Erskine 1Environmental Research Institute of the Supervising Scientist Darwin Australia 2School of Environmental and Life Sciences The University of Newcastle Ourimbah Campus Ourimbah Australia 3Research Institute for the Environment and Livelihoods Charles Darwin University Darwin Australia Environmental Research Institute of the Supervising Scientist Darwin Australia

The East Alligator River d.ains a 7000 km2 catchment in northern Australia comprised.largely of Aboriginal land.and.has a very low average population d.nsity of about 0.15 persons per km2. River reaches were classified.accord.ng to geomorphic features on both the East Alligator River and.its major tributary, Magela Creek, next to which is located.the Ranger uranium mine. Sixteen reaches were d.scribed.for the 241.4 km of the East Alligator River and.ten reaches were d.scribed.for the 118.8 km of Magela Creek. The d.minant river types on the East Alligator River were various types of anabranching rivers, sand.tone gorges and.cuspate tid.l meand.rs. On Magela Creek the d.minant river types were wetland. and.channel billabongs, island.anabranching and.sand.tone gorges. It is unusual for anabranching rivers and.gorges to be so d.minant. Current river classification schemes could.not accommod.te all the various river types and.need.to be mod.fied.so that tid.l channels are covered.in more d.tail and.so that the classification of anabranching rivers recognises that sand.bed.varieties occur in partly confined.valley settings.

关键词： River Reaches River Types Sand.tone Gorge Anabranching Rivers Cuspate Tid.l Meand.rs Wetland. and Channel Billabongs

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Evolution-aid.d.engineering of plant specialized.metabolism

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aBIOTECH 2021年第3期2卷 240-263页

作者： Mohammad.Irfan Benjamin Chavez Parid. Rizzo john C.d.Auria Gaurav d.Moghe Plant Biology Section School of Integrative Plant ScienceCornell UniversityIthacaNYUSA Metabolic d.versity Group Leibniz Institute of Plant Genetics and Crop Plant Research(IPK)06466 SeelandGermany

The evolution of new traits in living organisms occurs via the processes of mutation,recombination,genetic d.ift,and.*** processes that have resulted.in the immense biol ogical d.versity on our planet are also being employed.in metabolic engineering to optimize enzymes and.pathways,create new-to-nature reactions,and.synthesize complex natural prod.cts in heterologous *** this review,we d.scuss two evolution-aid.d.strategies for metabolic engineering-d.rected.evolution,which improves upon existing genetic templates using the evolutionary process,and.combinatorial pathway reconstruction,which brings together genes evolved.in d.fferent organisms into a single heterol ogous *** d.scuss the general principles of these strategies,d.scribe the technologies involved.and.the molecular traits they influence,provid. examples of their use,and.d.scuss the road.locks that need.to be ad.ressed.for their wid.r ad.ption.A better und.rstand.ng of these strategies can provid. an impetus to research on gene function d.scovery and.biochemical evolution,which is found.tional for improved.metabolic *** evolution-aid.d.approaches thus have a substantial potential for improving our und.rstand.ng of plant metabolism in general,for enhancing the prod.ction of plant metabolites,and.in sustainable agriculture.

关键词： Evolution Metabolic engineering Plant biotechnology Synthetic biology

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d.tection of Borrelia americana in the Avian Coastal Tick, Ixod.s auritulus (Acari: Ixod.d.e), Collected.from a Bird.Captured.in Canad.

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Open Journal of Animal Sciences 2016年第3期6卷 207-216页

作者： john d. Scott Janet E. Foley Research d.vision Lyme Ontario Fergus Canada d.partment of Med.cine and.Epid.miology School of Veterinary Medicine University of California Davis CA USA

We d.cument the first record.of Borrelia americana in Canad.. This Borrelia was d.tected.in an avian coast tick, Ixod.s auritulus (Acari: Ixod.d.e), collected.from a Varied.Thrush, Ixoreus naevius, along coastal British Columbia. Using real-time PCR and.d.A sequencing of the flagellin gene, we d.termined.that the borrelial amplicon from the I. auritulus nymph was 99% homologous with B. americana type strain SCW-41. Because patients infected.with B. americana can be seronegative for Lyme d.sease, med.cal professionals should.be willing to pursue molecular analyses and.consid.r treatment for patients with Lyme d.sease-like symptoms.

关键词： Borrelia americana Lyme d.sease Avian Coastal Tick Ixod.s auritulus Varied.Thrush Songbird Bird.Parasitism Canad.

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