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Saturn＇s gravitational field induced by its equatorially antisymmetric zonal winds

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

作者： dali Kong Keke Zhang Gerald Schubert john d.Anderson 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 department 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 winds of Saturn are marked by a substantial equatorially antisymmetric component with a speed of about 50 m s^-1 which, if they are sufficiently deep, can produce measurable odd zonal gravitational coefficients △J2 k＋1, k = 1, 2, 3, 4. This study, based on solutions of the thermal-gravitational wind equation, provides a theoretical basis for interpreting the odd gravitational coefficients of Saturn in terms of its equatorially antisymmetric zonal flow. We adopt a Saturnian model comprising an ice-rock core, a metallic dynamo 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 condition required for the thermal-gravitational wind equation. The structure and amplitude of the zonal flow at the cloud level are chosen to be consistent with observations of *** calculate the odd zonal gravitational coefficients △J2k＋1, k = 1, 2, 3, 4 by regarding the depth of the equatorially antisymmetric winds as a parameter. It is found that △J3 is-4.197 × 10^-8 if the zonal winds extend about 13 000 km downward from the cloud tops while it is-0.765 × 10^-8 if the depth is about 4000 km. The depth/profile of the equatorially antisymmetric zonal winds can eventually be estimated when the high-precision measurements of the Cassini Grand Finale become available.

关键词： gravitation - planets and satellites individual (Saturn) - planets and satellites interiors

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A model 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

We present an interior model 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 determined fully self-consistently by the required equilibrium *** the ice-rock core is assumed to have a uniform density,three different equations of state are adopted for the metallic,molecular and transition *** Saturnian model is constrained by its known mass,its known equatorial and polar radii,and its known zonal gravitational coefficients,J_（2n）,n=1,2,*** model produces an ice-rock core with equatorial radius 0.203 R_S,where R_S is the equatorial radius of Saturn at the 1-bar pressure surface;the core densityρ_c=10388.1 kgm^（3）corresponding to 13.06 Earth masses;and an analytical expression describing the Saturnian irregular shape of the 1-bar pressure *** model also predicts the values of the higher-order gravitational coefficients,J_8,J_10 and J_12,for the hydrostatic Saturn and suggests that Saturn’s convective dynamo operates in the metallic region approximately defined by 0.2 R_S

关键词： gravitation — planets and satellites individual(Saturn) — planets and satellites interiors

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Acute coronary syndromes： an old age problem

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Journal of Geriatric Cardiology 2012年第2期9卷 192-196页

作者： Alexander d Simms Philip d Batin john Kurian Nigel durham Christopher P Gale Centre for Epidemiology and Biostatistics Level 8 Worsley Building University of Leeds Clarendon Way West Yorkshire Leeds LS2 9JT UK Hull and York Medical School York Teaching Hospital NHS Foundation Trust York Y031 8HE UK department of Cardiology York Teaching Hospital NHS Foundation Trust York Y031 8HE UK department of Cardiology Mid Yorkshire NHS Trust Wakefield WF1 4DG UK department of Cardiology Bradford Teaching Hospital NHS Foundation Trust Bradford UK

The increasing population in older age will lead to greater numbers of them presenting with acute coronary syndromes （ACS）. This has implications on global healthcare resources and necessitates better management and selection for evidenced-based therapies. The elderly 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 discrepancy in care, to some extent, is explained by the higher frequency of atypical and delayed presentations in the elderly, and less diagnostic electrocardiograms at presentation, potentiating a delay in ACS diagnosis. Under estimation of mortality risk in the elderly due to limited consideration for physiological tiailty, co-morbidity, cognitive/psychological impairment and physical disability, less input by cardiology specialists and lack of randomised, controlled trials data to guide management in the elderly 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 elderly patients for specific therapies and medication regimens are unanswered. There is a growing need for randomised, controlled trial data to be more representative of the population and enroll those of advanced age with co-morbidity. A lack of reporting of adverse events, such as renal impairment post coronary angiography, in the elderly further limit risk benefit decisions. Substantial improvements in care of elderly ACS patients are required and should be advocated. 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-modifiable factors of age-related risk.

关键词： Acute coronary syndromes Elderly patients Inequalities of care Evidenced-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 Education(LORE)of dalhousie 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 department 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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Evolution-aided 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 Paride Rizzo john C.d'Auria Gaurav d.Moghe Plant Biology Section School of Integrative Plant ScienceCornell UniversityIthacaNYUSA Metabolic diversity 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 drift,and *** processes that have resulted in the immense biol ogical diversity on our planet are also being employed in metabolic engineering to optimize enzymes and pathways,create new-to-nature reactions,and synthesize complex natural products in heterologous *** this review,we discuss two evolution-aided strategies for metabolic engineering-directed evolution,which improves upon existing genetic templates using the evolutionary process,and combinatorial pathway reconstruction,which brings together genes evolved in different organisms into a single heterol ogous *** discuss the general principles of these strategies,describe the technologies involved and the molecular traits they influence,provide examples of their use,and discuss the roadblocks that need to be addressed for their wider adoption.A better understanding of these strategies can provide an impetus to research on gene function discovery and biochemical evolution,which is foundational for improved metabolic *** evolution-aided approaches thus have a substantial potential for improving our understanding of plant metabolism in general,for enhancing the production of plant metabolites,and in sustainable agriculture.

关键词： Evolution Metabolic engineering Plant biotechnology Synthetic biology

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Structural health monitoring of bridges in the State of Connecticut

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Earthquake Engineering and Engineering Vibration 2008年第4期7卷 427-437页

作者： Chengyin Liu Joshua Olund Alan Cardini Paul d＇Attilio Eric Feldblum john deWolf SP-SELLS Inc. Briarcliff Manor NY 10510 USA department of Civil and Environmental Engineering University of Connecticut 261 Glenbrook Rd Unit 2037 Storrs CT06269 USA dMJM Harris Boston MA 02110 USA Connecticut department of Transportation 280 West Street Rocky Hill CT 06067 USA

A joint effort between the Connecticut department of Transportation and the University of Connecticut has been underway for more than 20 years to utilize various structural monitoring approaches to assess different bridges in Connecticut. This has been done to determine the performance of existing bridges, refine techniques needed to evaluate different bridge components, and develop approaches that can be used to provide a continuous status of a bridge＇s structural integrity. This paper briefly introduces the background of these studies, with emphasis on recent research and the development of structural health monitoring concepts. This paper presents the results from three different bridge types： a post-tensioned curved concrete box girder bridge, a curved steel box-girder bridge, and a steel multi-girder bridge. The structural health monitoring approaches to be discussed have been successfully tested using field data collected during multi-year monitoring periods, and are based on vibrations, rotations and strains. The goal has been to develop cost-effective strategies to provide critical information needed to manage the State of Connecticut＇s bridge infrastructure.

关键词： structural integrity structural health monitoring field data vibrations

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Quantifying spatiotemporal variability in occupant exposure to an indoor airborne contaminant with an uncertain source location

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Building Simulation 2023年第6期16卷 889-913页

作者： john E.Castellini Jr Cary A.Faulkner Wangda Zuo Michael d.Sohn department of Mechanical Engineering University of Colorado BoulderUCB 427BoulderCO80309USA department Architectural Engineering The Pennsylvania State UniversityUniversity ParkPA16802USA National Renewable Energy National Laboratory GoldenCO80401USA Energy Analysis and Environmental Impacts division Lawrence Berkeley National Laboratory1 Cyclotron RoadBerkeleyCA94720USA

Well-mixed zone models are often employed to compute indoor air quality and occupant *** effective,a potential downside to assuming instantaneous,perfect mixing is underpredicting exposures to high intermittent concentrations within a *** such cases are of concern,more spatially resolved models,like computational-fluid dynamics methods,are used for some or all of the ***,these models have higher computational costs and require more input information.A preferred compromise would be to continue with a multi-zone modeling approach for all rooms,but with a better assessment of the spatial variability within a *** do so,we present a quantitative method for estimating a room’s spatiotemporal variability,based on influential room *** proposed method disaggregates variability into the variability in a room’s average concentration,and the spatial variability within the room relative to that *** enables a detailed assessment of how variability in particular room parameters impacts the uncertain occupant *** demonstrate the utility of this method,we simulate contaminant dispersion for a variety of possible source *** compute breathing-zone exposure during the releasing(source is active)and decaying(source is removed)*** CFd methods,we found after a 30 minutes release the average standard deviation in the spatial distribution of exposure was approximately 28%of the source average exposure,whereas variability in the different average exposures was lower,only 10%of the total *** also find that although uncertainty in the source location leads to variability in the average magnitude of transient exposure,it does not have a particularly large influence on the spatial distribution during the decaying period,or on the average contaminant removal *** systematically characterizing a room’s average concentration,its variability,and the spatial variability within the room important insights can be gain

关键词： uncertainty variability airborne contaminant spatiotemporal variability well-mixed heterogeneity

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development,validation,and transportability of several machine-learned,non-exercise-based VO_(2max)prediction models for older adults

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Journal of Sport and Health Science 2024年第5期13卷 611-620页

作者： Benjamin T.Schumacher Michael J.LaMonte Andrea Z.LaCroix Eleanor M.Simonsick Steven P.Hooker Humberto Parada Jr. john Bellettiere Arun Kumar Herbert Wertheim School of Public Health and Human Longevity Science University of California San DiegoLa JollaCA 92093USA department of Epidemiology and Environmental Health School of Public Health and Health ProfessionsUniversity at BuffaloState University of New YorkBuffaloNY 14214USA Translational Gerontology Branch Intramural Research ProgramNational Institute on AgingNational Institutes of HealthBaltimoreMD 21225USA College of Health and Human Services San Diego State UniversitySan DiegoCA 92182USA division of Epidemiology and Biostatistics School of Public HealthSan Diego State UniversitySan DiegoCA 92182USA University of California San diego Moores Cancer Center La JollaCA 92093USA Computer Science and Engineering and Halicioglu data Science Institute University of California San DiegoLa JollaCA 92093USA

Background:There exist few maximal oxygen uptake(VO_(2max))non-exercise-based prediction equations,fewer using machine learning(ML),and none specifically for older *** direct measurement of VO_(2max)is infeasible in large epidemiologic cohort studies,we sought to develop,validate,compare,and assess the transportability of several ML VO_(2max)prediction ***:The Baltimore Longitudinal Study of Aging(BLSA)participants with valid VO2_(max)tests were included(n=1080).Least absolute shrinkage and selection operator,linear-and tree-boosted extreme gradient boosting,random forest,and support vector machine(SVM)algorithms were trained to predict VO_(2max)*** developed these algorithms for:(a)the overall BLSA,(b)by sex,(c)using all BLSA variables,and(d)variables common in aging ***,we quantified the associations between measured and predicted VO_(2max)and ***:The age was 69.0±10.4 years(mean±Sd)and the measured VO_(2max)was 21.6±5.9 mL/kg/*** absolute shrinkage and selection operator,linear-and tree-boosted extreme gradient boosting,random forest,and support vector machine yielded root mean squared errors of 3.4 mL/kg/min,3.6 mL/kg/min,3.4 mL/kg/min,3.6 mL/kg/min,and 3.5 mL/kg/min,*** quartiles of measured VO_(2max)showed an inverse gradient in mortality *** VO_(2max)variables yielded similar effect estimates but were not robust to ***:Measured VO_(2max)is a strong predictor of *** ML can improve the accuracy of prediction as compared to simpler approaches but estimates of association with mortality remain sensitive to *** studies should seek to reproduce these results so that VO_(2max),an important vital sign,can be more broadly studied as a modifiable target for promoting functional resiliency and healthy aging.

关键词： Cardiorespiratory fitness Prediction algorithms Epidemiology Mortality

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Regression of recurrent granulosa cell tumor liver metastases following selective internal radiation therapy

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Hepatobiliary & Pancreatic diseases International 2023年第4期22卷 406-408页

作者： Omar A Mownah john d Leahy Jeffrey Summers Stephen M Gregory Nigel d Heaton Institute of Liver Studies King’s Healthcare PartnersKing’s College Hospital NHS Foundation TrustDenmark HillLondon SE59RSUK department of Oncology Maidstone and Tunbridge Wells NHS TrustMaidstone ME169QQUK

Granulosa cell tumor(GCT)is the most common sex cordstromal tumor,comprising 5%of all ovarian malignancies[1].The disease course is indolent,and the majority of cases present at stage ***,metastases may develop with potential sites being peritoneum,lung,brain,liver and bone[2].due to the rarity of the disease,published evidence for management of granulosa cell tumor liver metastases(GCTLM)is *** resection is the optimal treatment in instances where there is a high chance of achieving complete resection[3].With regards to unresectable GCTLM there is a paucity of evidence to guide treatment strategy.

关键词： metastases liver lung

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Wafer-scale quasi-layered tungstate-doped polypyrrole film with high volumetric capacitance

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Nano Research 2023年第4期16卷 4895-4900页

作者： Huabo Liu Jiaxing Liang john Watt Richard d.Tilley Rose Amal da-Wei Wang School of Chemical Engineering University of New South WalesSydneyNSW 2052Australia 2 Center for Integrated NanotechnologiesLos Alamos National LaboratoryLos AlamosNW 87545USA 3 School of ChemistryUniversity of New South WalesSydneyNSW 2052Australia

Layered materials are particularly attractive for supercapacitors because of their unique physical,electrical and chemical ***,we demonstrate a facile and scalable electrochemical deposition method for wafer-scale synthesis of quasilayered tungstate-doped polypyrrole films(named TALPy)with controllable thickness and *** as-prepared TALPy film exhibits a high gravimetric density and excellent volumetric capacitance,exceeding many high-performing carbon-and polymerbased film *** on combined results of ex-situ X-ray diffraction(XRd),Raman and X-ray photoelectron spectroscopy(XPS),it is determined that TALPy stores charge through an ion intercalation process accompanied by change in oxidation states of polypyrrole backbone,which is referred as intercalation *** these results suggest the great promise of electrochemical deposition as a scalable and controllable bottom-up approach for synthesizing quasi-layered conductive organic-inorganic hybrid films for electrochemical energy storage applications with high volumetric performance.

关键词： electrochemical deposition conductive polymer polypyrrole organic-inorganic hybrid supercapacitor intercalation pseudocapacitance

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