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基于决策树法分析在成年早期和中年期维持正常血压的因素：年轻人冠状动脉风险发展研究结果

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中华高血压杂志(中英文) 2022年第5期 500-500页

作者：袁源周卫郑武洪 Reges O Krefman AE Hardy ST Yano Y Muntner P Lloyd-Jones DM allen nb

对于大多数人来说，血压与多种危险因素有关。本研究旨在应用决策树法确定与维持正常血压时间>30年的相关因素及各因素之间的相互作用，并揭示哪类人群维持正常血压的概率更高。方法：纳入中青年人冠状动脉危险因素研究（coronary arter...

对于大多数人来说，血压与多种危险因素有关。本研究旨在应用决策树法确定与维持正常血压时间>30年的相关因素及各因素之间的相互作用，并揭示哪类人群维持正常血压的概率更高。方法：纳入中青年人冠状动脉危险因素研究（coronary artery risk development in young adults study,CARDIA）中基线检查（Y0,1985-1986）时血压水平正常的年龄18～30岁参与者。结果：在参与者3 156人中，在随访期间维持正常血压水平1 132人（35.9%），血压升高2 024人（64.1%）。中年时期正常血压者与血压升高者间差异有统计学意义的因素包括正常范围内的收缩压、种族和体质量指数（body mass index,BMI）。

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综合代谢特征可改善年轻人的心血管病风险预测

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中华高血压杂志 2020年第11期28卷 1099-1099页

作者： Murthy VL Reis JP Pico AR Kitchen R Lima JAC Lloyd-Jones D allen nb Carnethon M Lewis GD Nayor M Vasan RS Freedman JE Clish CB Shah RV 刘青(译) 刘莉(摘/审校) 不详

虽然心血管病指标定义了年龄≥40岁个体的风险,但心血管病的最早期病变在40岁以前就出现了。尽管代谢在心血管病先兆中起重要作用,然而在年轻、混血人群中确定精确代谢风险的研究尚缺乏。研究者获取青年冠状动脉风险发展(coronary arter... 详细信息

虽然心血管病指标定义了年龄≥40岁个体的风险,但心血管病的最早期病变在40岁以前就出现了。尽管代谢在心血管病先兆中起重要作用,然而在年轻、混血人群中确定精确代谢风险的研究尚缺乏。研究者获取青年冠状动脉风险发展(coronary artery risk development in young adults,CARDIA)研究中的2330名白人和非洲裔青年(平均年龄32岁,45%为非洲裔)资料进行分析,以确定代谢情况与20年后不良心血管病现象(心肌结构/功能、适应性、血管钙化)、机制及预后的相关性。

关键词：早期病变代谢情况心血管病心肌结构血管钙化代谢特征指标定义 artery

Potentially dangerous glacial lakes across the Tibetan Plateau revealed using a large-scale automated assessment approach

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Science Bulletin 2019年第7期64卷 435-445页

作者： Simon Keith allen Guoqing Zhang Weicai Wang TANDong Yao Tobias Bolch Department of Geography University of Zurich Key Laboratory of Tibetan Environmental Changes and Land Surface Processes Institute of Tibetan Plateau Research Chinese Academy of Sciences Center for Excellence in Tibetan Plateau Earth Sciences Chinese Academy of Sciences School of Geography and Sustainable Development University of St Andrews

Glacial lake outburst floods(GLOFs) are a major concern in the Himalaya and on the Tibetan Plateau(TP),where several disasters occurring over the past century have caused significant loss of life and damage to infrastructure. This study responds directly to the needs of local authorities to provide guidance on the most dangerous glacial lakes across TP where local monitoring and other risk reduction strategies can subsequently be targeted. Specifically, the study aims to establish a first comprehensive prioritisation ranking of lake danger for TP, considering both the likelihood and possible magnitude of any outburst event(hazard), and the exposure of downstream communities. A composite inventory of 1,291 glacial lakes(>0.1 km^2) was derived from recent remote sensing studies, and a fully automated and object assessment scheme was implemented using customised GIS tools. Based on four core determinates of GLOF hazard(lake size, watershed area, topographic potential for ice/rock avalanching, and dam steepness), the scheme accurately distinguishes the high to very high hazard level of 19 out of 20 lakes that have previously generated GLOFs. Notably, 16% of all glacial lakes threaten human settlements, with a hotspot of GLOF danger identified in the central Himalayan counties of Jilong, Nyalam, and Dingri, where the potential trans-boundary threat to communities located downstream in Nepal is also recognised. The results provide an important and object scientific basis for decision-making, and the methodological approach is ideally suited for replication across other mountainous regions where such first-order studies are lacking.

关键词： GLOF Hazard Exposure Danger Tibetan Plateau Himalaya

Convergent plate boundary environments for formation of≥3800 Ma mafic-ultramafic assemblages(Isua area,Greenland):Implications for early global geodynamics

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Geoscience Frontiers 2024年第3期15卷 119-136页

作者： allen P.Nutman Clark R.L.Friend Vickie C.Bennett School of Earth Atmospheric and Life SciencesUniversity of WollongongWollongongNSW 2522Australia Glendale TiddingtonOxon OX92LQUK Research School of Earth Sciences Australian National UniversityCanberraACT 2601Australia

In the gneiss terrane on the south side of the Eoarchean Isua supracrustal belt,ultramafic rocks with relict abyssal peridotite mineralogy(Bennett et al.,2002;Friend et al.,2002;Nutman et al.,2007;Rollinson,2007;van de Löcht et al.,2020),layered gabbros with cumulate ultramafic rocks,basalts and associated siliceous sedimentary rocks were tectonically-imbricated,prior to and during intrusion of ca.3800 Ma *** with3800 Ma basalts in the Outer Arc Group of the nearby Isua supracrustal belt,the composition of all these mafic rocks(e.g.,Th-Hf-nb systematics,high Th/Yb,Ba/nb,Ba/Yb ratios and negative nb and Ti anomalies)shows affinity with modern suprasubduction rocks whose genesis involved fluid fluxing of the upper ***,the majority of these samples have Ba/nb and Ba/Yb values less than in modern island arc magmas,but similar to many backarc basin magmas(e.g.,Pearce and Stern,2006).It is unknown whether these ca.3800 Ma mafic rocks are,(i)arc rocks where the Ba/nb and Ba/Yb signatures reflect lower surficial Ba in Eoarchean oceanic settings,or(ii)in direct comparison with Phanerozoic suites,these signatures reflect a back-arc setting with interplay between fluid fluxing and decompressional *** tectonic intercalation of upper mantle with lower and upper crustal rocks,combined with the fluid-fluxing influences seen in chemistry of all the mafic rocks is best accommodated in a compressional Eoarchean convergent plate boundary setting within a mobile-lid *** stagnant lid scenarios of crust formation,if operative,must have co-existed or alternated with mobile-lid regimes by 3800 Ma.

关键词： Eoarchean Fluid-fluxing Plate tectonics Suprasubduction Crustal evolution

Mercury bioaccumulation in aquatic biota along a salinity gradient in the Saint John River estuary

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Journal of Environmental Sciences 2018年第6期30卷 41-54页

作者： Bethany L.Reinhart Karen A.Kidd R.allen Curry Nelson J.O’Driscoll Scott A.Pavey Department of Biology and Canadian Rivers Institute University of New Brunswick Saint John Saint John New Brunswick E2L4L5 Canada Department of Biology Forestry and Environmental Management and Canadian Rivers Institute University of New Brunswick Fredericton New Brunswick E3B4A3 Canada Department of Earth and Environmental Sciences Acadia University Wolfville Nova Scotia B4P2R6 Canada Department of Biology and School of Geography & Earth Sciences McMaster University Hamilton Ontario LSS 4K1 Canada

Although estuaries are critical habitats for many aquatic species, the spatial trends of toxic methylmercury（MeHg） in biota from fresh to marine waters are poorly understood. Our objective was to determine if MeHg concentrations in biota changed along a salinity gradient in an estuary. Fourspine Stickleback（Apeltes quadracus）, invertebrates（snails,amphipods, and chironomids）, sediments, and water were collected from ten sites along the Saint John River estuary, New Brunswick, Canada in 2015 and 2016, with salinities ranging from 0.06 to 6.96. Total mercury（proxy for MeHg） was measured in whole fish and MeHg was measured in a subset of fish, pooled invertebrates, sediments, and water. Stable sulfur（δ34S）, carbon（δ13 C）, and nitrogen（δ15N） isotope values were measured to assess energy sources（S, C） and relative trophic level（N）. There were increases in biotic δ13C and δ34S from fresh to more saline sites and these measures were correlated with *** aqueous MeHg was higher at the freshwater than more saline sites, only chironomid MeHg increased significantly with salinity. In the Saint John River estuary, there was little evidence that MeHg and its associated risks increased along a salinity gradient.

关键词： Stickleback Amphipod Methylmercury Biomagnification Stable isotopes Food web

The Pushtashan juvenile suprasubduction zone assemblage of Kurdistan (northeastern Iraq): A Cretaceous (Cenomanian) Neo-Tethys missing link

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Geoscience Frontiers 2017年第5期8卷 1073-1087页

作者： Sabah A.Ismail Sarmad A.Ali allen P.Nutman Vickie C.Bennett Brain G.Jones Department of Applied Geology College of Sciences Kirkuk University Kirkuk 36001 Iraq GeoQuEST Research Centre School of Earth & Environmental Sciences University of Wollongong Wollongong NSW 2522 Australia Research School of Earth Sciences Australian National University ACT 0200 Australia

The Pushtashan suprasubduction zone assemblage of volcanic rocks, gabbros, norites and peridotites occurs in the Zagros suture zone, Kurdistan region, northeastern Iraq. Volcanic rocks are dominant in the assemblage and consist mainly of basalt and basaltic andesite flows with interlayered red shale and limestone horizons. Earlier lavas tend to be MORB-like, whereas later lavas display island arc tholeiite to boninitic geochemical characteristics. Tholeiitic gabbros intrude the norites and display fractionation trends typical of crystallisation under low-pressure conditions, whereas the norites display calc-alkaline traits, suggesting their source included mantle metasomatised by fluids released from subducted oceanic crust. Enrichment of Rb, Ba, Sr, Th and the presence of negative nb anomalies indicate generation in a suprasubduction zone setting. Trondhjemite and granodiorite intrusions are present in the volcanic rocks, gabbros and norites. SHRIMP U-Pb dating of magmatic zircons from a granodiorite yields a mean^(206)Pb/^(238)U age of 96.0 ±2.0 Ma(Cenomanian). The initial ε_(Hf) value for the zircons show a narrow range from +12.8 to+15.6, with a weighted mean of + 13.90±0.96. This initial value is within error of model depleted mantle at 96 Ma or slightly below that, in the field of arc rocks with minimal contamination by older continental crust. The compositional bimodality of the Pushtashan suprasubduction sequence suggests seafloor spreading during the initiation of subduction, with a lava stratigraphy from earlyerupted MORB transitioning into calc-alkaline lavas and finally by 96 Ma intrusion of granodioritic and trondhjemitic bodies with juvenile crustal isotopic signatures. The results confirm another Cretaceous arc remnant preserved as an allochthon within the Iraqi segment of the Cenozoic Zagros suture zone. Implications for the closure of Neo-Tethys are discussed.

关键词： Pushtashan suprasubduction assemblage Cretaceous Zircon U-Pb dating Hf isotopes Kurdistan region lraq Neo-Terhys

广东龙窝花岗闪长质岩体的年代学、地球化学及岩石成因

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岩石学报 2004年第6期20卷 1363-1374页

作者：邱检生胡建 McInnes B I A 蒋少涌徐夕生 allen C M 南京大学成矿作用国家重点实验室南京210093 南京大学地球科学系南京210093 CSIRO Exploration & Mining Australian Resources Research Centre Kensington WA 6151 Research School of Earth Sciences Australian National University Canberra ACT 0200

龙窝岩体是南岭地区燕山早期具幔源组分贡献的花岗岩的典型代表,其主体岩性为花岗闪长岩,岩体中含有深色闪长质包体,锆石ELA-ICP-MS定年结果表明花岗闪长岩的形成年龄为169.1±2.5Ma,属中侏罗世岩浆活动的产物。地球化学特征上,该岩体... 详细信息

龙窝岩体是南岭地区燕山早期具幔源组分贡献的花岗岩的典型代表,其主体岩性为花岗闪长岩,岩体中含有深色闪长质包体,锆石ELA-ICP-MS定年结果表明花岗闪长岩的形成年龄为169.1±2.5Ma,属中侏罗世岩浆活动的产物。地球化学特征上,该岩体铝弱过饱和(A/NKC=1.0～1.1),相对贫碱,富钾(K_2O/Na_2O=1.15～1.45),富轻稀土和大离子亲石元素(如Rb、Cs、Th、U),贫高场强元素(如nb、Ti)。闪长质包体具有与寄主岩相似的矿物组合,但铁镁矿物含量及过渡族元素(V、CR、Co、Ni)丰度相对偏高,二者的主量和微量元素表现出混合成因的演化趋势。寄主岩与包体具有相近的Sr、Nd同位素组成,I_(Sr)和ε_(Nd)(t)值分别为0.70843～0.70995、-6.53～-8.89和0.70797～0.70882、-4.71～-9.24,均表现出壳幔混源花岗岩类岩石的特点。二元混合模拟计算显示寄主岩与包体成岩过程中地幔物质的混入比例分别为32.9％～40.4％和 31.8％～46.4％。通过对岩石产出构造背景及地质地球化学特征的综合分析,表明龙窝花岗闪长岩及其中的闪长质包体是在伸展-引张环境下,由幔源基性岩浆及其诱发的壳源长英质岩浆混合作用的产物。

关键词：花岗闪长岩闪长质包体锆石ELA-ICP-MS定年地球化学岩石成因广东龙窝岩体