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Geochemistry of Middle Holocene Sediments from South Yellow Sea: Implications to Provenance and Climate Change

Journal of Earth Science 2016年第5期27卷 751-762页

作者： Xiaoxia Lii gerard J. M. Versteegh Jinming Song Xuegang Li Huamao Yuan Ning Li Faculty of Marine Sciences China University of Geosciences State Key Laboratory of Biogeology and Environmental Geology China University of Geosciences Heisenberg Group on Marine Kerogen Center for Marine Environmental Sciences (MARUM) Bremen University Institute of Oceanology Chinese Academy of Sciences

From a large number of case studies on terrestrial deposits we know that Late Holocene climate fluctuations have an important impact on the terrestrial environments. However, it is hitherto not clear how the marine sediments can be used to shed light on the environment and climate change of the catchment. To provide such insight, we used the major element, trace element and rare earth element（REE） compositions in the southern Yellow Sea（SYS） sediments to reconstruct the changes in weathering and erosion of their source regions. The sediments originate predominantly from the upper crust of East China and are transported into the basin especially by the Yellow River（Huanghe） and to a lesser extent by the Yangtze River（Changjiang）. The chemical index of alteration（CIA; 53.7–59.7） suggests low chemical weathering of the source rocks since the Middle Holocene. This is consistent with the relatively cool and arid climate in North China after the Holocene Megathermal. Comparison of element ratios, including Al/Ca, K/Ca, Al/Na, K/Na, Rb/Sr, Li/Ba and the CIA shows that we can use the latter as a robust proxy for climate change. The CIA-based mean annual precipitation and mean annual temperature show a series of climate fluctuations in the catchment. A relatively warm and humid Period I（5.3–2.9 cal. ka BP）, a relatively cool and dry Period II（2.9–0.9 cal. ka BP） and an increasingly cool and dry Period III（0.9–0.3 cal. ka BP）. These periods can be linked to climate intervals recognized elsewhere.

关键词： geochemical composition elemental ratio climate change provenance South YellowSea sediment.

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Evolution of the East China Sea sedimentary environment in the past 14 kyr: Insights from tetraethers-based proxies

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Science China Earth Sciences 2016年第5期59卷 927-938页

作者： GE HuangMin ZHANG ChuanLun VERSTEEGH gerard J.M. CHEN LingLing FAN DaiDu DONG Liang LIU JingJing State Key Laboratory of Marine Geology Tongji University Hadal Science and Technology Research Center (Shanghai Engineering Research Center of Hadal Science and Technology) Shanghai Ocean University Heisenberg Group on Marine Kerogen Center for Marine Environmental Sciences (MARUM) Bremen University

We reconstruct the environmental evolution of the East China Sea in the past 14 kyr based on glycerol dialkyl glycerol tetraethers(GDGTs) in a sediment core from the subaqueous Yangtze River Delta. Two primary phases are recognized. Phase I(13.8–8 cal kyr BP) reflects a predominantly continental influence, showing distinctly higher concentrations of branched GDGTs(averaged 143 ng/g dry sediment weight, dsw) than isoprenoid GDGTs(averaged 36 ng/g dsw), high BIT index(branched vs. isoprenoid tetraethers) values(>0.78) and a fluctuating GDGT-0/crenarchaeol ratio(R_(0/5), varied from 0.52 to 3.81). Within this interval, temporal increases of terrestrial and marine influence are attributed to Younger Dryas(YD)(ca. 12.9–12.2 cal kyr BP) cold event and melt-water pulse(MWP)-1B(11.5–11.1 cal kyr BP), respectively. The prominent transition from 8 to 7.9 cal kyr BP shows a sharp decrease in BIT index value(<0.4) and increase in crenarchaeol, which marks the beginning of phase II. Afterwards, the proxies remain relatively constant, which indicates that phase II(7.9 cal kyr BP-present) is a shelf sedimentary environment with high stand of sea level. Overall, the BIT index in our record serves as a good marker for terrestrial influence at the site, and likely reflects the flooding history of the region. The TEX_(86)(Tetra Ether Index of tetraethers consisting of 86 carbons) proxy is not applicable in phase I because of an excess terrestrial influence; but it seems to be valid for revealing the annual SST in phase II(21.6±0.9°C, n=49). In contrast, the MBT'/CBT(Methylation of Branched Tetraethers and Cyclization of Branched Tetraethers) proxy appears to faithfully record the annual mean air temperature(MAT)(14.3±0.63°C, n=68) and presents an integrated signal over the middle and lower Yangtze River drainage basin.

关键词： GDGTs Proxies Sedimentary environment evolution Holocene East China Sea

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Ultrasound Pulse Emission Spectroscopy Method to Characterize Xylem Conduits in Plant Stems

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Research 2023年第1期2022卷 139-152页

作者： Satadal Dutta Zhiyi Chen Elias Kaiser Priscilla Malcolm Matamoros Peter G.Steeneken gerard J.Verbiest Department of Precision and Microsystems Engineering Faculty of 3METU DelfMekelweg 22628CD DelfNetherlands Horticulture and Product Physiology Department of Plant SciencesWageningen University and ResearchDroevendaalsesteeg 6708PB WageningenNetherlands

Although it is well known that plants emit acoustic pulses under drought stress,the exact origin of the waveform of these ultrasound pulses has remained ***,we present evidence for a correlation between the characteristics of the waveform of these pulses and the dimensions of xylem conduits in *** a model that relates the resonant vibrations of a vessel to its dimension and viscoelasticity,we extract the xylem radi from the waveforms of ultrasound pulses and show that these are correlated and in good agreement with optical *** demonstrate the versatility of the method by applying it to shoots of ten different vascular plant *** particular,for Hydrangea quercifolia,we further extract vessel element lengths with our model and compare them with scanning electron *** ultrasonic,noninvasive characterization of internal conduit dimensions enables a breakthrough in speed and accuracy in plant phenotyping and stress detection.

关键词： dimensions breakthrough Pulse

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Classifying Groups of Small Order

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Advances in Pure Mathematics 2016年第2期6卷 58-65页

作者： gerard Thompson Department of Mathematics and Statistics The University of Toledo Toledo OH USA

The classification of groups of order less than 16 is reconsidered. The goal of the paper is partly historical and partly pedagogical and aims to achieve the classification as simply as possible in a way which can be easily incorporated into a first course in abstract algebra and without appealing to the Sylow Theorems. The paper concludes with some exercises for students.

关键词： Finite Group Dihedral Group Historical Pedagogical

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Social Myths： A New Approach

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Journal of Philosophy Study 2016年第6期6卷 356-366页

作者： gerard Bouchard Universite du Quebec a Chicoutimi

Nowadays, the study of myths is rather neglected as a field of research in sociology. There is a void that this paper would like to contribute to filling. It outlines a theoretical and empirical sociological approach to social myths as a major component of collective imaginaries and a universal sociological mechanism through time and space. The article recalls the major functions performed by myths in every society （modem as well as ＂primitive＂）, introduces new concepts, and sets forth an analytical framework designed to account for the emergence, the reproduction, and the decline of myths, as sacralised collective representations.

关键词： social myths archemyths mythification process discursive strategies

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基于递归最小二乘支持向量机的动态系统建模研究

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控制与决策 2009年第11期24卷 1663-1667,1672页

作者：瞿海妮许维胜 DREYFUS gerard 同济大学电子信息工程学院上海201804 巴黎高等理工化工学校巴黎75005

针对递归最小二乘支持向量机的递归性易导致建模中偏微分方程组求解困难的问题,提出用解析法求解偏微分方程组,实现了完整的递归最小二乘支持向量机模型.首先分析了各参数的相关性,然后推导出偏微分方程的解析表达式并求解.仿真实例表明... 详细信息

针对递归最小二乘支持向量机的递归性易导致建模中偏微分方程组求解困难的问题,提出用解析法求解偏微分方程组,实现了完整的递归最小二乘支持向量机模型.首先分析了各参数的相关性,然后推导出偏微分方程的解析表达式并求解.仿真实例表明,在动态系统建模中,该模型的性能比常用的串并联模型以及现有不完整递归最小二乘支持向量机模型的精度更高、性能更好.

关键词：递归最小二乘支持向量机非线性偏微分方程

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Experimental models of metabolic and alcoholic fatty liver disease

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World Journal of Gastroenterology 2021年第1期27卷 1-18页

作者： Delfin gerard Buyco Jasmin Martin Sookyoung Jeon Royce Hooks Chelsea Lin Rotonya Carr Division of Gastroenterology University of PennsylvaniaPhiladelphiaPA 19104United States

Non-alcoholic fatty liver disease(NAFLD)is a multi-systemic disease that is considered the hepatic manifestation of metabolic syndrome(MetS).Because alcohol consumption in NAFLD patients is common,there is a significant overlap in the pathogenesis of NAFLD and alcoholic liver disease(ALD).Indeed,MetS also significantly contributes to liver injury in ALD ***“syndrome of metabolic and alcoholic steatohepatitis”(SMASH)is thus expected to be a more prevalent presentation in liver patients,as the obesity epidemic *** pre-clinical experimental models that couple alcohol consumption with NAFLDinducing diet or genetic obesity have been developed to better understand the pathogenic mechanisms of *** models indicate that concomitant MetS and alcohol contribute to lipid dysregulation,oxidative stress,and the induction of innate immune *** are significant limitations in the applicability of these models to human disease,such as the ability to induce advanced liver injury or replicate patterns in human food/alcohol ***,there remains a need to develop models that accurately replicate patterns of obesogenic diet and alcohol consumption in SMASH patients.

关键词： Non-alcoholic fatty liver disease Alcoholic liver disease Non-alcoholic steatohepatitis Animal models Insulin resistance Oxidative stress

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计及分布式电源和负荷静态特性的最优低频减载

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华南理工大学学报（自然科学版） 2011年第10期39卷 139-145页

作者：刘志鹏文福拴 gerard Ledwich 华南理工大学电力学院广东广州510640 浙江大学电气工程学院浙江杭州310027 昆士兰科技大学工程系统系

低频减载被认为是当电力系统发生频率严重下降事故时所能采取的最后一项补救措施.针对配电系统中的低频减载问题,文中提出了计及分布式电源和负荷静态特性的最优低频减载策略.该策略以频率及频率变化率为执行依据,并由几个基本轮和一个... 详细信息

低频减载被认为是当电力系统发生频率严重下降事故时所能采取的最后一项补救措施.针对配电系统中的低频减载问题,文中提出了计及分布式电源和负荷静态特性的最优低频减载策略.该策略以频率及频率变化率为执行依据,并由几个基本轮和一个特殊轮组成.在基本轮中,按反馈控制律分轮次快速切除负荷,以保证频率摆脱紧急状态.而在特殊轮中,则优化分布式电源的出力和调整部分负荷,以保证频率恢复到安全状态并使系统运行参数最优.最后,以修改的IEEE 37节点配电系统为例来验证所提出的最优低频减载策略的有效性.

关键词：配电系统分布式电源低频减载基本轮特殊轮负荷静态特性

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Impact of fine particles in ambient air on lung cancer

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Chinese Journal of Cancer 2014年第4期33卷 197-203页

作者： gerard Hoek Ole Raaschou-Nielsen Institute for Risk Assessment Sciences Utrecht University Danish Cancer Society Research Center

Recently,the International Agency for Research on Cancer(IARC)has classified outdoor air pollution and the particulate matter component of outdoor air pollution as class I *** pollution is consistently associated with lung cancer in epidemiologic and experimental *** IARC assessment is specifically designed as hazard identification,and it does not quantify the magnitude of the cancer *** article addresses the magnitude of the lung cancer risk in the population due to ambient air pollution exposure.

关键词：环境空气污染肺癌微粒研究机构流行病学危害识别癌症颗粒物

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Changes in ecosystem carbon stocks in a grassland ash (Fraxinus excelsior) afforestation chronosequence in Ireland

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Journal of Plant Ecology 2014年第5期7卷 429-438页

作者： Michael L.Wellock Rashad Rafique Christina M.LaPerle Matthias Peichl gerard Kiely Centre for Hydrology Micrometeorology and Climate ChangeDepartment of Civil and Environmental EngineeringUniversity College CorkCorkIreland Department of Microbiology and Plant Biology University of OklahomaNormanOK 73019USA Department of Forest Ecology and Management Swedish University of Agricultural SciencesUmeåSweden

Aims Government policy in Ireland is to increase the national forest cover from the current 10%to 18%of the total land area by *** represents a major land use change that is expected to impact on the national carbon(C)*** the C stocks of ecosystem bio-mass and soils of Irish grasslands and coniferous forests have been quantified,little work has been done to assess the impact of broad-leaf afforestation on C *** In this study,we sampled a chronosequence of ash(Fraxinus excel-sior)forests aged 12,20,27,40 and 47 years on brown earth soils.A grassland site,representative of the pre-afforestation land use,was sampled as a *** Findings Our results show that there was a significant decline(P<0.05)in the carbon density of the soil(0-30 cm)following afforestation from the grassland(90.2 Mg C ha^(−1))to the 27-year-old forest(66.7 Mg C ha^(−1)).Subsequently,the forest soils switched from being a C source to a C sink and began to sequester C to 71.3 Mg C ha^(−1) at the 47-year-old *** found the amount of C stored in the above-and belowground biomass increased with age of the forest stands and offset the amount of C lost from the *** amount of C stored in the above-and belowground biomass increased on average by 1.83 Mg C ha^(−1) year^(−1).The increased storage of C in the biomass led to an increase in the total ecosystem C,from 90.2 Mg C ha^(−1) at the grassland site to 162.6 Mg C ha^(−1) at the 47-year-old *** a national scale,projected rates of ash afforestation to the year 2020 may cause a loss of 290752 Mg C from the soil compared to 2525936 Mg C sequestered into the tree *** effects of harvesting and reforestation may further modify the development of ecosystem C stocks over an entire ash rotation.

关键词： ash(Fraxinus excelsior L.) chronosequence soil biomass carbon ecosystem

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