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高纬度地震台网数据对地球内核各向异性的约束

2014年中国地球科学联合学术年会——专题7：核幔边界和地核的结构及动力学

作者：马晓龙孙新蕾 wiens,d.a. Nyblade,A. Anandakrishnan,S. Aster,R. Huerta,A. Wilson,T. 中国科学院广州地球化学研究所同位素地球化学国家重点实验室 department of Earth and Planetary Sciences Washington University (St.Louis) department of Geosciences Pennsylvania State University department of Earth & Environmental Science New Mexico Tech department of Geological Sciences Central Washington University department of Geological Sciences Ohio State University

PKP前导波早在1930年代就已经被发现(Gutenberg and Richter,1934)。全球台网的PKP前导波研究表明它们是由于整个地幔,主要是下地幔均匀分布的%速度不均匀结构引起的(Hedlin and Shearer,2000)。近年来,随着局部密集台网的增加,研究表...

PKP前导波早在1930年代就已经被发现(Gutenberg and Richter,1934)。全球台网的PKP前导波研究表明它们是由于整个地幔,主要是下地幔均匀分布的%速度不均匀结构引起的(Hedlin and Shearer,2000)。近年来,随着局部密集台网的增加,研究表明这些台网记录到的PKP前导波主要是由于核幔边界附近的不均匀结构引起的,并且这些结构的速度异常可以达到5-6%甚至10%(e.g.,Niu and Wen,2001;Vidale and Hedlin,1998)。PKP前导波的到时和振幅,可以为核幔边界不均匀结构的位置,形态,速度和密度异常提供有用的信息,有利于我们更好地理解核幔边界的性质和动力学过

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高纬度地震台网数据对地球内核各向异性的约束

Phenotypic plasticity is maintained despite geographical isolation in an African cichlid fish,Pseudocrenilabrus multicolor

2014年中国地球科学联合学术年会——专题7：核幔边界和地核的结构及动力学

作者：秦加岭孙新蕾 wiens,d.a. Nyblade,A. Anandakrishnan,S. Aster,R. Huerta,A. Wilson,T. 中国科学院广州地球化学研究所同位素地球化学国家重点实验室 department of Earth and Planetary Sciences Washington University (St.Louis) department of Geosciences Pennsylvania State University department of Earth & Environmental Science New Mexico Tech department of Geological Sciences Central Washington University department of Geological Sciences Ohio State University

了解地球内核的结构以及组分,对研究地球的演化和地球动力学有着重要意义。之前的地震学研究已经表明,地球内核的各向异性是复杂的三维结构(Sun and Song,2008a;Isshi and dziewonski,2002)。然而,由于地震数据的分布不均匀性,穿过地核...

了解地球内核的结构以及组分,对研究地球的演化和地球动力学有着重要意义。之前的地震学研究已经表明,地球内核的各向异性是复杂的三维结构(Sun and Song,2008a;Isshi and dziewonski,2002)。然而,由于地震数据的分布不均匀性,穿过地核中心部分以及靠近内核边界部分的南北向PKP数据明显不足,使得这些区域的结构存在一定的争议和空白(deuss et al,2013;Sun and Song,2008b;Niu and Wen 2001)。要获得穿过内核深部的近南北向的PKP数据,要求地震和台站分别位于地球的两极附近。近年来

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Integrative Zoology 2014年第1期9卷 85-96页

作者： Kirsten E.wiens Erika CRISPO Lauren J.CHAPMAN department of Pathology New York University School of MedicineNew YorkNYUSA department of Biology and Health Sciences Pace UniversityNew YorkNYUSA department of Biology McGill UniversityMontrealQuebecCanada Wildlife Conservation Society BronxNew YorkUSA

Gene flow among populations in different selective environments should favor the evolution of phenotypic plasticity over local *** in development is a common response to long-term hypoxia in some widespread.a.rican fishes,including Pseudocrenilabrus multicolor,a cichlid that exploits both normoxic(high oxygen)rivers/lakes and hypoxic(low oxygen)*** studies have shown that fish from normoxic and hypoxic sites differ in many traits,including gill size,brain size and body shape,and that much of this vari-ation reflects developmental ***,these earlier studies focused on areas in Uganda where gene flow between swamp and river or lake populations is *** this study we tested the hypothesis that ***-color from a relatively isolated lake population(Lake Saka,Uganda)exhibit low levels of plasticity in traits re-lated to oxygen *** broods of *** from Lake Saka were reared under low and high dis-solved oxygen,and traits related to gill size,brain mass and body shape were ***,both gill size and brain mass showed high levels of developmental *** suggest that high levels of plasticity,particularly in the gill size of ***,reflects low costs of maintaining the plastic response,even in rela-tively isolated populations.

关键词： brain geometric morphometrics gills hypoxia riverine fish

A new focus on risk reduction: an ad hoc decision support system for humanitarian relief logistics

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Ecosystem Health and Sustainability 2015年第3期1卷 1-12页

作者： Frank Schatter Marcus wiens Frank Schultmann Karlsruhe Instilute of Technology(KIT) Institute for Industrial Production(IIP)HertzstraBe 16Karlsruhe 76187 Germany University of Adelaide EntrepreneurshipCommercialisationand Innovation Centre(ECIC).Level 510 Pulteney StretAdelaideSouth Australia 5005 Australia

Particularly in the early phases of a disaster,logistical decisions are needed to be made quickly and under high pressure for the decision-makers,knowing that their decisions may have direct consequences on the affected society and.a.l future *** risk reduction may be helpful in providing decision-makers with optimal strategies in ***,disasters are characterized by severe uncertainty and complexity,limited knowledge about the causes of the disaster,and continuous change of the situation in unpredicted *** these assumptions,we believe that adequate proactive risk reduction measures are not *** propose strengthening the focus on ad hoc decision support to capture information in almost real time and to process information efficiently to reveal uncertainties that had not been previously ***,we present an ad hoc decision support system that uses scenario techniques to capture uncertainty by future developments of a situation and.a. optimization model to compute promising decision *** combining these aspects in a dynamic manner and integrating new information continuously,it can be ensured that a decision is always based on the best currently available and processed *** finally,to identify a robust decision option that is provided.a. a decision recommendation to the decision-makers,methods of multi-attribute decision making(MAdM)are *** approach is illustrated for a facility location decision problem arising in humanitarian relief logistics where the objective is to identify robust locations for tent hospitals to serve injured people in the immed.a.e aftermath of the Haiti Earthquake 2010.

关键词： ad hoc decision support humanitarian relief logistics information and communication tecmology multi-criteria decision analysis public safety-critical supply chains robustness scenario techniques

Missing data and the accuracy of Bayesian phylogenetics

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植物分类学报 2008年第3期46卷 307-314页

作者： John J. wiens daniel S. MOEN department of Ecology and Evolution Stony Brook University Stony Brook NY 11794-5245 USA

The effect of missing data on phylogenetic methods is a potentially important issue in our attempts to reconstruct the Tree of Life. If missing data are truly problematic, then it may be unwise to include species in an analysis that lack data for some characters (incomplete taxa) or to include characters that lack data for some species. Given the difficulty of obtaining data from all characters for all taxa (e.g., fossils), missing data might seriously impede efforts to reconstruct a comprehensive phylogeny that includes all species. Fortunately, recent simulations and empirical analyses suggest that missing data cells are not themselves problematic, and that in-complete taxa can be accurately placed.a. long as the overall number of characters in the analysis is large. How-ever, these studies have so far only been conducted on parsimony, likelihood, and neighbor-joining methods. Although Bayesian phylogenetic methods have become widely used in recent years, the effects of missing data on Bayesian analysis have not been adequately studied. Here, we conduct simulations to test whether Bayesian analyses can accurately place incomplete taxa despite extensive missing data. In agreement with previous studies of other methods, we find that Bayesian analyses can accurately reconstruct the position of highly incomplete taxa (i.e., 95% missing data), as long as the overall number of characters in the analysis is large. These results suggest that highly incomplete taxa can be safely included in many Bayesian phylogenetic analyses.

关键词：贝叶斯定理系统发生学数据缺失准确度

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富氯造岩矿物中溴的分子结构

地学前缘 2020年第5期27卷 10-22页

作者： Yuanming Pan Ning Chen Jianfeng Zhu Neelege Hopps Eli wiens Jinru Lin department of Geological Sciences University of SaskatchewanSaskatoonSK S7N 5E2Canada Canad.a. Light Source University of SaskatchewanSaskatoonSK S7N 0X4Canada Saskatchewan Structural Sciences Centre University of SaskatchewanSK S7N 5C9Canada Key Laboratory of Pollution Ecology and Environmental Engineering Institute of Applied EcologyChinese Academy of SciencesShenyangLiaoning 110016P.R.China

卤族元素诸如氯和溴作为地球化学示踪剂,常用于指示岩浆、变质岩和热液的来源和演化过程。而认清溴在造岩矿物中的形态和结构有助于丰富和完善其在地质环境演变中的示踪作用。但是,溴在造岩矿物中的含量极低导致大多数结构分析方法都无... 详细信息

卤族元素诸如氯和溴作为地球化学示踪剂,常用于指示岩浆、变质岩和热液的来源和演化过程。而认清溴在造岩矿物中的形态和结构有助于丰富和完善其在地质环境演变中的示踪作用。但是,溴在造岩矿物中的含量极低导致大多数结构分析方法都无法使用,因此造岩矿物中微量溴的结构研究极具挑战性。本文采用81Br魔角旋转核磁共振(MAS NMR)光谱和同步辐射吸收光谱(XAS)技术,首次对富氯造岩矿物中的微量溴进行了结构分析。结果表明溴离子在方硼石中的微区结构不同于该矿物中三配位Cl原子的结构环境,而与Mg3B7O13Br中八面体配位的溴离子相似,表明即使在微量条件下也存在域偏析。而对其他富氯造岩矿物的Br K边X光吸收近边结构(XANES)光谱白线峰的位置和扩展X射线吸收精细结构(EXAFS)分析表明微量溴离子替代了这些矿物中氯的位置,导致局部结构扭曲膨胀。溴离子在造岩矿物中的这一微观结构研究结果可为探索氯和溴在地质演变过程的指示作用提供新的科学依据。

关键词：卤族元素溴造岩矿物魔角旋转核磁共振 X光吸收光谱地球化学示踪

A frozen collision belt beneath ice:an overview of seismic studies around the Gamburtsev Subglacial Mountains,East Antarctica

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Ad.a.ces in Polar Science 2016年第2期27卷 78-89页

作者： AN Meijian douglas A.wiens ZHAO Yue Institute of Geomechanics Chinese Academy of Geological SciencesBeijing 100081China department of Earth and Planetary Science Washington UniversitySt.LouisMO 63130MissouriUSA

The Gamburtsev Antarctic Mountains Seismic Experiment （GAMSEIS, 2007-2010） was jointly conducted by the United States, China, and Japan during and.a.ter the International Polar Year 2007-2008. Broad.a.d seismic stations were deployed.a.ross the ice-covered Gamburtsev Subglacial Mountains （GSM） and other previously unexplored.a.eas in the interior of East Antarctica. Using GAMSEIS data, published results not only have revealed the deep structure of Antarctica, but also improved our understanding of the tectonic evolution of Antarctica and the supercontinent Gond.a.a, and of the relationship between geothermal heat flux and glaciers. This contribution d.a.s together the major findings from recent studies, and.a.so offers further investigation into the relationship between tectonic history and the East Antarctic Ice Sheet. The elevation of the GSM is largely supported by thickened crust, with Moho depths of ~60 km near the crest of the range. The GSM are underlain by thick （〉200 km） and cold continental lithosphere that likely formed.a.ter collision of two ancient crustal blocks during the pan-African orogeny. Heat flux results obtained from seismic inversion support a model of ice sheet basal melting that depends more strongly on bedrock topography than on geothermal heat flux, while ice surface and ice thickness are inversely correlated with heat flux.

关键词： GAMSEIS crust lithosphere ice sheet Gond.a.a International Polar Year

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南极中山站-昆仑站间地壳厚度分布

极地研究 2014年第2期26卷 177-185页

作者：冯梅安美建安春雷史贵涛赵越李院生 douglas wiens 中国地质科学院地质力学研究所北京100081 中国极地研究中心上海200136 department of Earth and Planetary Science Washington University

自第4个国际极地年2007/2008开始至2013年,中国南极内陆冰盖科考队相继在自南极大陆边缘的中山站至东南极地形最高点昆仑站(dome A)一线进行了低温甚宽频地震观测。本文对7个天然地震台站数据进行了分析,提取了这些台站的S波接收函数,... 详细信息

自第4个国际极地年2007/2008开始至2013年,中国南极内陆冰盖科考队相继在自南极大陆边缘的中山站至东南极地形最高点昆仑站(dome A)一线进行了低温甚宽频地震观测。本文对7个天然地震台站数据进行了分析,提取了这些台站的S波接收函数,据此反演获得了这些台站下的地壳厚度分布。结果显示:随着纬度的升高,地壳厚度由大陆边缘的中山站下的约38 km逐渐增加至CHNB台下的58 km,随后又于CHNA台站下方减薄至47 km,然后快速增大到南极地形最高点昆仑站(dome A)下的62 km。昆仑站或dome A是南极大陆地壳最厚的地方。从中山站至昆仑站之间地壳厚度的变化与冰下地貌变化存在明显的相关性,它们都说明了从中山站至CHNB之间地壳构造相对均匀。在距昆仑站约200 km的CHNA台下的地壳厚度(约47 km)明显比临近台站地壳偏薄,这可能说明了甘伯采夫山脉地壳侧向变化较大,即其形成时所遭受的构造作用较复杂。

关键词：地壳厚度接收函数昆仑站东南极南极内陆科考

Biosilica-glass formation using enzymes from sponges [silicatein]： Basic aspects and.a.plication in biomedicine [bone reconstitution material and osteoporosis]

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Frontiers of Computer Science 2011年第3期5卷 266-281页

作者： Shun-Feng WANG Xiao-Hong WANG Lu GAN Matthias wiens Heinz C. SCHROdER Werner E, G. MOLLER Werner E. G. MOLLER National Research Center for Geoanalysis Chinese Academy of Geological Sciences 26 Baiwanzhuang Dajie Beijing 100037 China Institute of Physiological Chemistry University Medical Center of the Johannes Gutenberg University Mainz Duesbergweg 6 D-55128 Mainz Germany

In the last 15 years biomineralization, in particular biosilicification （i.e., the formation of biogenic silica, SiO2）, has become an exciting source of inspiration for the development of novel bionic approaches, following ＂Nature as model＂. Among the silica forming organisms there are the sponges that have the unique property to catalyze their silica skeletons by a specific enzyme termed silicatein. In the present review we summarize the present state of knowledge on silicatein-med.a.ed ＂biosilica＂ formation in marine sponges, the involvement of further molecules in silica metabolism and their potential application in biomedicine. Recent ad.a.cements in the production of bone replacement material and in the potential use as a component in the treatment of osteoporosis are highlighted.

关键词： biomineralization biosilica medicine biomaterials osteoporosis