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From the Early Paleozoic Platforms of Baltica and Laurentia to the Caledonide Orogen of Scandinavia and Greenland

Episodes 2008年第1期31卷 44-51页

作者： David G. Gee Haakon Fossen niels Henriksen Anthony K. Higgins Department of Earth Sciences Uppsala University Villavagen Villavaeigen 16 Uppsala SE-752 36 Sweden. Department of Earth Science University of Bergen Allegaten 41 N-5007 Bergen Norway. The Geological Survey of Denmark and Greenland Фster Voldgade 10 Dk 1350 Copenhagen Denmark.

The Caledonide Orogen in the Nordic countries is exposed in Norway, western Sweden, westernmost Finland, on Svalbard and in northeast Greenland. In the mountains of western Scandinavia, the structure is dominated by E-vergent thrusts with allochthons derived from the Baltoscandian platform and margin, from outboard oceanic （lapetus） terranes and with the highest thrust sheets having Laurentian affinities. The other side of this bivergent orogen is well exposed in northeastern Greenland, where W-vergent thrust sheets emplace Laurentian continental margin assemblages onto the platform. Svalbard＇s Caledonides are disrupted by late Caledonian faults, but have close affinity with the Laurentian margin in Northeast Greenland. Only Svalbard＇s Southwestern terrane is foreign to this margin, showing affinity, to the Pearya terrane of northern Ellesmere Island in arctic Canada. Between the margins of western Scandinavia and eastern Greenland, the wide continental shelves, now covered by late Paleozoic and younger successions, are inferred to be underlain by the Caledonide hinterland, probably incorporating substantial Grenville-age basement. In northernmost Norway, the NE-trending Caledonian thrust front truncates the NW-trending Neoproterozoic Timanide orogen of northwest Russia. Much of the central and eastern parts of the Barents Shelf are thought to be underlain by Caledonian-deformed Timanide basement. Caledonian orogeny in Norden resulted from the closure of the Iapetus Ocean and Scandian collision of continent Baltica with Laurentia. Partial subduction of the Baltoscandian margin beneath Laurentia in the midlate Silurian was followed by rapid exhumation of the highly metamorphosed hinterland in the early Devonian, and deposition of Old Red Sandstones in intramontane basins. Late Scandian collapse of the orogen occurred on major extensional detachments, with defor mation persisting into the late Devonian.

关键词：古生代平台劳伦古大陆斯堪的纳维亚造山地带格陵兰岛

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Is the Export-led Growth Hypothesis Enough to Account for China's Growth?

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China & World Economy 2010年第4期18卷 34-51页

作者： María jesús Herrerias Vicente Orts Department of Economics and lnstitut of International Economics Universitat Jaume I Department of Economics Universitat Jaume I

One of the missing pieces preventing us from understanding recent Chinese economic development is the role played by openness and capital accumulation in this process. The question is whether the sharp economic＇ growth that the Chinese economy has experienced is another case of export-led growth due to the open-door policy or whether, on the contrary, this growth has been caused by high domestic savings and investment rates （and the consequent capital accumulation）. To answer this question, we employed an empirical framework of the cointegrated vector autoregressive model. The empirical results show that both investment （in physieal capital and R＆D） and exports, as well as the exchange rate policy, are relevant factors in explaining China＇s long-run economic growth over the past 4 decades.

关键词： investment labor productivity openness output

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Control of tendon cell fate in the embryonic limb: A molecular perspective

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BIOCELL 2023年第3期47卷 465-471页

作者： jesSICA CRISTINA MARÍN-LLERA CARLOS AMAURY JIMÉNEZ-CÁRDENAS jesÚS CHIMAL-MONROY Departamento de Medicina Genómica y Toxicología Ambiental Instituto de Investigaciones BiomédicasUniversidad Nacional Autónoma de México Ciudad UniversitariaApartado Postal 70228MéxicoDF 04510México

The molecular cascade underlying tendon formation starts when progenitor cells begin to express the Scleraxis(Scx)*** knockout mice develop some but not all tendons,suggesting that additional factors are necessary for tendon commitment,maintenance,and *** transcription factors,such as Mohawk(Mkx)or early growth response(Egr),maintain Scx expression and extracellular matrix formation during *** inhibition of wingless and int-related protein signaling is necessary and sufficient to induce the expression of *** the commitment of tenogenic lineage occurs,transforming growth factor-beta(TGFβ)induces the Scx gene expression,becoming involved in the maintenance of tendon cell *** this point of view,we discussed two phases of the tenogenic process during limb development:dependent and independent of mechanical ***,we highlight the importance of understanding embryonic tendon development to improve therapeutic strategies in regenerative medicines for tendons.

关键词： Tendon differentiation Tenocyte Scleraxis Mohawk Early growth response Tendon development WNT TGFβ

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Implications of tree species–environment relationships for the responsiveness of Himalayan krummholz treelines to climate change

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Journal of Mountain Science 2017年第3期14卷 453-473页

作者： niels SCHWAB Udo SCHICKHOFF Birgit BURZLE Michael MULLER Jurgen BOHNER Ram Prasad CHAUDHARY Thomas SCHOLTEN Jens OLDELAND CEN Center for Earth System Research and Sustainability Institute of GeographyUniversity of HamburgBundesstrafle 5520146 HamburgGermany Department of Geosciences Chair of Soil Science and CeomorphologyUniversity of TübingenGermany Research Centre for Applied Science and Technology&Central Department of Botany Tribhuvan UniversityNepal Biocentre Klein Flottbek University of HamburgOhnhorststr.1822609 HamburgGermany

Climate warming is expected to advance treelines to higher elevations. However, empirical studies in diverse mountain ranges give evidence of both advancing alpine treelines as well as rather insignificant responses. In this context, we aim at investigating the sensitivity and responsiveness of the near-natural treeline ecotone in Rolwaling Himal, Nepal, to climate warming. We analysed population densities of tree species along the treeline ecotone from closed forest stands via the krummholz belt to alpine dwarf shrub heaths （3700-4200 m） at 50 plots in 2013 and 2014. We quantified species - environment relationships, i.e. the change of environmental conditions （e.g., nutrient and thermal deficits, plant interactions） across the ecotone by means of redundancy analyses, variation partitioning and distance-based Moran＇s eigenvector maps. In particular, we focus on explaining the high competitiveness of Rhododendron campanulatum forming a dense krummholz belt and on the implications for the responsiveness of Himalayan krummholz treelines to climate change. Results indicate that treeline trees in the ecotone show species-specific responses to the influence of environmental parameters, and that juvenile and adult tree responses are modulated by environmental constraints in differing intensity. Moreover, the species - environment relationships suggest that the investigated krummholz belt will largely prevent the upward migration of other tree constrain the future response species and thus of Himalayan krummholz treelines to climate warming.

关键词： Himalaya Nepal Population structure Rhododendron campanulatum Spatial patterns Species-environment relationships Stand density Variation partitioning

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Software Vulnerabilities Overview:A Descriptive Study

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Tsinghua Science and Technology 2020年第2期25卷 270-280页

作者： Mario Calín Sánchez Juan Manuel Carrillo de Gea José Luis Fernández-Alemán jesús Garcerán Ambrosio Toval the Department of Informatics and Systems Faculty of Computer ScienceUniversity of Murcia

Computer security is a matter of great *** the last decade there have been numerous cases of cybercrime based on the exploitation of software *** fact has generated a great social concern and a greater importance of computer security as a *** this work,the most important vulnerabilities of recent years are identified,classified,and categorized individually.A measure of the impact of each vulnerability is used to carry out this classification,considering the number of products affected by each vulnerability,as well as its *** addition,the categories of vulnerabilities that have the greatest presence are *** on the results obtained in this study,we can understand the consequences of the most common vulnerabilities,which software products are affected,how to counteract these vulnerabilities,and what their current trend is.

关键词： descriptive study software security software vulnerabilities vulnerability databases

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Emerging bisphenol a replacements(colour developers)in indoor dust from Spain

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Emerging Contaminants 2019年第1期5卷 168-172页

作者： María jesús Duenas-Mas Ana Ballesteros-Gomez Soledad Rubio Department of Analytical Chemistry Institute of Fine Chemistry and NanochemistryMarie Curie Building AnnexCampus of RabanalesUniversity of Cordoba14071CordobaSpain

Bisphenol A(BPA)and replacements,such as bisphenol S(BPS)and F(BPF)and other substitutes(BPSMAE,D-8 and TGSA)have been recently reported in thermal *** this study,BPA,BPS,BPF;BPS-MAE,D-8 and TGSA were analysed in indoor dust collected in Spain from different microenvironments(living rooms,bedrooms,cars and offices).Levels were compared with those reported in our previous study(shops and other public microenvironments,where frequent use of thermal paper is expected).We investigated the differences between microenvironments,possible correlations between compounds and estimated the ingestion ***-MAE,D-8 and TGSA were present at levels up to 529,128 and 356 ng g^-1,respectively,in all the *** highest levels were measured in cars.

关键词： Bisphenol A Bisphenol F Bisphenol S BPS-MAE D-8 TGSA Indoor dust

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Complex patterns of environmental niche evolution in Iberian columbines (genus Aquilegia, ranunculaceae)

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Journal of Plant Ecology 2015年第5期8卷 457-467页

作者： Rafael Jaime Julio M.Alcántara jesús M.Bastida Pedro J.Rey Departamento de Biología Animal Biología Vegetal y EcologíaUniversidad de JaénCampus Las Lagunillass/n.Jaén E-23071Spain

Aims This study explores the patterns of niche differentiation in a group of seven closely related columbines(genus Aquilegia,ranunculaceae)from the Iberian *** of these columbines are subject to complex patterns of divergent selection across environ-ments,which partly explain the taxonomic structure of the *** suggests the hypothesis that niche divergence must have occurred along the process of diversification of the *** We used maxEnt to build environmental niche models of seven subspecies belonging to the three species of Aquilegia present in the Iberian *** these models,we compared the envi-ronmental niches through two different approaches:ENmtools and multivariate *** FindingsmaxEnt distributions conformed closely to the actual distribution of the study *** methods failed to uncover any clear patterns of niche differentiation or conservatism in Iberian *** analyses indicate the existence of dif-ferentiation along altitudinal gradients and along a gradient of climatic conditions determined by the summer precipitation and ***,climatic conditions related to winter tem-perature and precipitation,as well as soil properties,were equally likely to show conservatism or *** complex patterns of niche evolution we found suggest that Iberian Columbines have not been significantly constrained by forces of niche conservatism,so they could respond adaptively to the fast and profound climate changes in the Iberian Peninsula through the glacial cycles of the Pleistocene.

关键词： Aquilegia ecological niche modelling niche divergence niche conservatism evolution maxEnt ENmTools

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Therapy with stem cells in inflammatory bowel disease

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World Journal of Gastroenterology 2014年第5期20卷 1211-1227页

作者： María del Pilar Martínez-Montiel Gonzalo jesús Gómez-Gómez Ana Isabel Flores IBD Unit Department of Gastroenterology Universitary Hospital 12 Octubre Medicine Regenerative Group Investigation Center 12 Octubre Investigation Institute

Inflammatory bowel disease (IBD) affects a part of the young population and has a strong impact upon quality of life. The underlying etiology is not known, and the existing treatments are not curative. Furthermore, a significant percentage of patients are refractory to therapy. In recent years there have been great advances in our knowledge of stem cells and their therapeutic applications. In this context, autologous hematopoietic stem cell transplantation (HSCT) has been used in application to severe refractory Crohn’s disease (CD), with encouraging results. Allogenic HSCT would correct the genetic defects of the immune system, but is currently not accepted for the treatment of IBD because of its considerable risks. Mesenchymal stem cells (MSCs) have immune regulatory and regenerative properties, and low immunogenicity (both autologous and allogenic MSCs). Based on these properties, MSCs have been used via the systemic route in IBD with promising results, though it is still too soon to draw firm conclusions. Their local administration in perianal CD is the field where most progress has been made in recent years, with encouraging results. The next few years will be decisive for defining the role of such therapy in the management of IBD.

关键词： Mesenchymal stem cell, Inflammatory bowel disease, Crohn’ s disease, Ulcerative colitis, Haematopoietic stem cell transplantation

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Proton Exchange Membranes for Fuel Cells Challenges and Recent Developments

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复旦学报（自然科学版） 2005年第5期44卷 666-667页

作者： Jens Oluf Jensen Pernille P. Noyé niels J. Bjerrum Materials Science Group Department of Chemistry Technical University of DenmarkMaterials Science Group Department of Chemistry Technical University of DenmarkMaterials Science Group Department of Chemistry Technical University of Denmark

The current technology of proton exchange membrane fuel cells (PEMFC) is based on perfluorosulfonic acid (PFSA) membranes (e. g. Nafion(R)) as electrolyte. It operates on pure hydrogen and oxygen/air at typically 80℃ with high power density and long-term durability. For the membranes to be conductive, a minimum threshold of absorbed water molecules is about 6 to 7 mole per sulfonic site. The highest conductivity is only obtained under fully hydrated conductions, i.e. 21 - 22 mole water per sulfonic acid site. In other words, the proton conductivity is achieved by the locally liquid-like hydrophilic domain of the *** strong dependence of conductivity on the water content in membranes limits the operational temperatureof PEMFC below 100℃.

关键词：质子交换燃料电池隔膜电化学电解液

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Exploiting Additive Manufacturing Infill in Topology Optimization for Improved Buckling Load

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Engineering 2016年第2期2卷 250-257页

作者： Anders Clausen niels Aage Ole Sigmund Section of Solid Mechanics Department of Mechanical Engineering Technical University of Denmark Lyngby DK-2800 Denmark

Additive manufacturing （AM） permits the fabrication of functionally optimized components with high geometrical complexity. The opportunity of using porous infill as an integrated part of the manufactur- ing process is an example of a unique AM feature. Automated design methods are still incapable of fully exploiting this design freedom. In this work, we show how the so-called coating approach to topology optimization provides a means for designing infill-based components that possess a strongly improved buckling load and, as a result, improved structural stability. The suggested approach thereby addresses an important inadequacy of the standard minimum compliance topology optimization approach, in which buckling is rarely accounted for; rather, a satisfactory buckling load is usually assured through a post-processing step that may lead to sub-optimal components. The present work compares the stan- dard and coating approaches to topology optimization for the MBB beam benchmark case. The opti- mized structures are additively manufactured using a filamentary technique. This experimental study validates the numerical model used in the coating approach. Depending on the properties of the infill material, the buckling load may be more than four times higher than that of solid structures optimized under the same conditions.

关键词： Additive manufacturingIn fillTopology optimizationBuckling

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