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trade-offs between ecosystem service provision and the predisposition to disturbances: a NFI-based scenario analysis

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Forest Ecosystems 2020年第3期7卷 349-365页

作者： Christian temperli Clemens Blattert Golo Stadelmann Urs-Beat Brändli Esther thürig Swiss Federal Institute for Forest Snow and Landscape Research WSL8903BirmensdorfSwitzerland University of Jyväskylä FI-40014JyväskyläFinland

Background: Scenario analyses that evaluate management effects on the long-term provision and sustainability of forest ecosystem services and biodiversity(ESB) also need to account for disturbances. the objectives of this study were to reveal potential trade-offs and synergies between ESB provision and disturbance predisposition at the scale of a whole ***: the empirical scenario model MASSIMO was used to simulate forest development and management from years 2016 to 2106 on 5086 sample plots of the Swiss National Forest Inventory(NFI). We included a businessas-usual(BAU) scenario and four scenarios of increased timber harvesting. Model output was evaluated with indicators for 1) ESB provision including a) timber production, b) old-growth forest characteristics as biodiversity proxies and c) protection against rockfall and avalanches and 2) for a) storm and b) bark beetle ***: the predisposition indicators corresponded well(AUC: 0.71–0.86) to storm and insect(mostly bark beetle)damage observations in logistic regression models. Increased timber production was generally accompanied with decreased predisposition(storm: >-11%, beetle: >-37%, depending on region and scenario), except for a scenario that promoted conifers where beetle predisposition increased(e.g. + 61% in the Southern Alps). Decreased disturbance predisposition and decreases in old-growth forest indicators in scenarios of increased timber production revealed a trade-off situation. In contrast, growing stock increased under BAU management along with a reduction in conifer proportions, resulting in a reduction of beetle predisposition that in turn was accompanied by increasing old-growth forest indicators. Disturbance predisposition was elevated in NFI plots with high avalanche and rockfall protection ***: By evaluating ESB and disturbance predisposition based on single-tree data at a national scale we bridged a gap between detailed, stand-scale assessments and

关键词： Disturbance Ecosystem services Empirical model Forest inventory Scenario analysis

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沥青自修复微胶囊研究进展

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材料导报 2020年第15期34卷 15092-15101页

作者：何亮黄胡端 Wim Van den bergh tóth Csaba 高杰 Karol Kowalski Jan Valentin 重庆交通大学交通土建材料国家地方联合实验室重庆400074 长安大学特殊地区公路工程教育部重点实验室西安710061 安特卫普大学应用工程学院比利时安特卫普G.Z.352 布达佩斯技术与经济大学土木工程学院匈牙利布达佩斯H-1521 华沙理工大学土木工程学院波兰华沙00-637 捷克理工大学土木工程学院捷克布拉格16629

微胶囊技术在世界上已应用于多个领域,包括医药、食品和化工等,具有广阔的应用前景。将微胶囊引入到沥青材料自修复中,可提高沥青材料的自修复能力并在裂缝产生初期即可自我修复,延长路面使用寿命。与传统的裂缝修补方法相比,微胶囊自... 详细信息

微胶囊技术在世界上已应用于多个领域,包括医药、食品和化工等,具有广阔的应用前景。将微胶囊引入到沥青材料自修复中,可提高沥青材料的自修复能力并在裂缝产生初期即可自我修复,延长路面使用寿命。与传统的裂缝修补方法相比,微胶囊自修复技术具有节能减排、降低养护成本和防止微裂缝扩展至宏观裂缝等优势。然而,沥青自修复微胶囊技术仍处于初步探索阶段,将微米级微胶囊应用于沥青材料自修复领域还存在着微胶囊强度控制范围不够明确,微胶囊破裂理论尚不成熟,且微胶囊制备工艺参数设计尚不统一等问题。因此,研究者们除研究制备工艺的影响外,还主要从选择合适的制备工艺影响参数和微胶囊的结构与性能方面不断尝试,并取得了丰硕的成果。随着制备工艺的不断成熟和影响参数的不断优化,经原位聚合法制备的微胶囊结构致密、性能优良。目前对掺微胶囊的沥青材料自修复的研究仍存在对沥青材料自修复提升效果的评价方法和评价指标尚不统一等问题。掺微胶囊的沥青材料自修复效果主要通过不同的指标来体现,包括延度、复数模量、拉伸强度、试件的载荷和沥青混合料的疲劳寿命等。其中,还对掺微胶囊的沥青混合料进行了路用性能研究。通过不同的评价指标表明,微胶囊显著提升了沥青材料的自修复效果;掺微胶囊的沥青混合料的水稳定性和高温稳定性略有下降,低温抗裂性下降较大,但仍满足规范要求。为总结沥青自修复微胶囊的研究进展,本文对比分析了多种自修复微胶囊制备方法的优势和特点,解析了影响微胶囊质量的主要因素(芯壁比、反应温度、终点pH值、乳化转速、酸化时间),总结了微胶囊的结构与性能的表征方法,介绍了掺微胶囊沥青材料自修复性能的评价方法与提升效果,阐述了微胶囊对沥青混合料路用性能的影响,探讨了借助分子动力学手段研究掺微胶囊的沥青材料自修复行为理论的可行性并展望了其未来发展前景,以期为微米级微胶囊的应用与发展提供参考。

关键词：沥青材料自修复微米级微胶囊制备与性能分子动力学

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the Challenging Place of Natural Hazards in Disaster Risk Reduction Conceptual Models:Insights from Central Africa and the European Alps

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International Journal of Disaster Risk Science 2020年第3期11卷 316-332页

作者： Caroline Michellier Patrick Pigeon André Paillet théodore trefon Olivier Dewitte Francois Kervyn Natural Hazards Service Royal Museum for Central Africa3080 TervurenBelgium EDYtEM Laboratory Universite de Savoie-Mont-Blanc73376 Le Bourget du lacFrance Geodynamics and Mineral Resources Service Royal Museum for Central Africa3080 TervurenBelgium

Based on a literature review and two case studies,this article presents the difficulties inherent in the main disaster risk reduction conceptual *** method used to highlight such evidence is to compare two programs on disaster risk reduction with mainstream conceptual *** authors participated in these programs,which were confronted with the need to integrate contributions and insights from both earth and social *** analysis found that the existing main conceptual models were unable to do justice to disaster risk reduction *** finding encouraged us to critique these *** effort led us to present possible solutions to compensate for the shortcomings of current models while taking into account the contextualization and dynamics of phenomena,as well as grappling with the more explicit integration of hazards and hazard risk into model design.

关键词： Central Africa Conceptual models Disaster risk reduction Natural hazards Northern French Alps

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Iterative signal reconstruction of deliberately clipped SMt signals

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Science China(Information Sciences) 2014年第2期57卷 5-17页

作者： KOLLR Zsolt GAZDA Juraj HORVth Pter VARGA Lajos KOCUR Duan Budapest University of technology and Economics technical University of Koice

Staggered Multitone(SMt)is a modulation technique showing significantly reduced Adjacent Channel Leakage Ratio(ACLR)resulting in a more compact Power Spectrum Density(PSD)for the transmitted signal,than the well-known and already widely adopted Orthogonal Frequency Division Multiple Access(OFDMA)***,the unique spectral properties of an SMt signal could be degraded by a non-linear element(e.g.a Power Amplifier(PA))in the *** baseband clipping can be applied to the transmitted signal,reducing the notable high Peak-to-Average Power Ratio(PAPR).the objective of this paper is to give a brief introduction to the SMt scheme,with a special emphasis on deliberate clipping efects and their *** paper introduces two receiver-oriented iterative methods aiming at the restoration of the baseband Bit Error Rate(BER)performance of a non-clipped *** methods are evaluated and compared based on numerical *** paper concludes with the selection of a possible candidate for use in systems applying deliberately clipped SMt signals.

关键词： clipping SMt iterative decoding nonlinear distortion PAPR

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Evolutionary history and phylogeography of Scots pine (Pinus sylvestris L.) in Europe based on molecular markers

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Journal of Forestry Research 2017年第4期28卷 637-651页

作者： Endre Gy. to′th Zolta′n A. Kobolkuti Andrzej Pedryc Ma′ria Hohn Department of Botany Szent Istva′n University Me′nesi u′t 44Budapest 1118 Hungary Department of Genetics and Plant Breeding Szent Istva′n UniversityMe′nesi u′t 44Budapest 1118Hungary

In this review we summarized recent historical records and molecular studies on evolutionary history and phylogeography of Scots pine with focus on the European highly fragmented distribution area of the species. Fossilized pollen, plant micro- and macrofossil records provided evidences on the large-scale species’ range shifts and demographic changes during the Quaternary. Populations of Scots pine were documented both in the glacial (incl. full glaciation) and interglacial periods. Recolonization of Europe after the glaciation originated from the (Sub) Mediterranean areas like the Balkan Peninsula but also from around the Eastern Alps and the surroundings of the Danube plain. Fennoscandia and northern European Baltic regions were most probably colonized from two main directions, from Western Europe and from the Russian Plain. Modern history of Scots pine was hardly affected by anthropogenic activities that started to strengthen in the Bronze and Iron Age. Along with the fossil records, molecular genetic tools were used to infer the origin and putative history including migration, differentiation and demography of the species. In this paper we compiled the major publications (30) of molecular genetic studies of the past 20 years derived from distinctly inherited organelle genomes (mitochondrial, chloroplast, nuclear) revealed by different marker systems (mtDNA-cox1, -nad1, -nad3, -nad7, ISSR, cpSSR, nSSR, B-SAP, SNP). It is important to consider that different phylogeographic patterns can be drawn by the analysis of different DNA marker types. Accordingly the use of more than one marker simultaneously outlines the most sophisticated phylogeographical pattern on the genetic lineages and can reveal high differentiation of the European distribution. Combined marker systems and markers derived from coding sequences have also been used to detect species’ phylogeographic patterns, but these were rarely applied to Scots pine. Although new molecular techniques can provide h

关键词： Molecular genetic markers Phylogeography Pinus sylvestris Quaternary history Refugia

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SYNthESIS OF MESOPOROUS CHROMIUM SILICAtE

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Chinese Chemical Letters 1995年第12期6卷 1091-1094页

作者： Yuan, ZY Chen, th Wang, JZ Li, HX Liu, SQ Nankai Univ Dept Chem Catalysis Lab Tianjin 300071 Peoples R China Nankai Univ Catalyst Plant Tianjin 300071 Peoples R China

A mesoporous chromium silicate molecular sieve with MCM-41 structure has beers prepared by direct hydrothermal synthesis; XRD; framework IR, ESR and DR-UV spectroscopies provided evidence of the presence of framework ...

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tracking market and non-traditional sources of risks in procyclical and countercyclical hedge fund strategies under extreme scenarios:a nonlinear VAR approach

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Financial Innovation 2022年第1期8卷 696-751页

作者： François-Éric Racicot Raymond théoret telfer School of Management University of Ottawa55 Laurier Avenue EastOttawaONCanada IPAG Business School ParisFrance École des Sciences de la Gestion Universitédu Québec(Montréal)315 est Ste-CatherineR2915MontréalQCCanada Chaire d’Information Financière et Organisationnelle ESG-UQAMMonntréalQuébecUniversitédu Québec(Outaouais)MontréalCanada

the subprime crisis was quite damaging for hedge *** the local projection method(Jordà2004,2005,2009),we forecast the dynamic responses of the betas of hedge fund strategies to macroeconomic and financial shocks—especially volatility and illiquidity shocks—over the subprime crisis in order to investigate their market timing *** a robustness check,using tVAR(Balke 2000),we simulate the reaction of hedge fund strategies’betas in extreme scenarios allowing moderate and strong adverse *** results show that the behavior of hedge fund strategies regarding the monitoring of systematic risk is highly nonlinear in extreme scenarios—especially during the subprime *** find that countercyclical strategies have an investment technology which differs from procyclical *** crises,the former seek to capture non-traditional risk premia by deliberately increasing their systematic risk while the later focus more on minimizing *** results suggest that the hedge fund strategies’betas respond more to illiquidity uncertainty than to illiquidity risk during *** find that illiquidity and VIX shocks are the major drivers of systemic risk in the hedge fund industry.

关键词： Hedge fund Procyclicality Illiquidity risk shock Illiquidity uncertainty shock Local projection model tVAR Optimal forecast Measurement errors

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Water-Soluble Gd(III)−Porphyrin Complexes Capable of Both Photosensitization and Relaxation Enhancement

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Chemical & Biomedical Imaging 2023年第2期1卷 157-167页

作者： tamas Nemeth Naoko Yoshizawa-Sugata Agnes Pallier Youichi tajima Yue Ma Éva tóth Hisao Masai Yoko Yamakoshi Department of Chemistry and Applied Biosciences ETH ZürichCH8093 ZürichSwitzerland Research Center for Genome&Medical Sciences Tokyo Metropolitan Institute of Medical ScienceSetagayaTokyo 156-8506Japan Centre de Biophysique Moléculaire CNRS UPR 4301University of Orléans45071 Cedex 2 OrléansFrance Department of Basic Medical Sciences Tokyo Metropolitan Institute of Medical ScienceSetagayaTokyo 156-8506Japan

With the aim of developing more stable Gd(III)−porphyrin complexes,two types of ligands 1 and 2 with carboxylic acid anchors were *** to the N-substituted pyridyl cation attached to the porphyrin core,these porphyrin ligands were highly water-soluble and formed the corresponding Gd(III)chelates,Gd-1 and ***-1 was sufficiently stable in neutral buffer,presumably due to the preferred conformation of the carboxylateterminated anchors connected to nitrogen in the meta position of the pyridyl group helping to stabilize Gd(III)complexation by the porphyrin center.1H NMRD(nuclear magnetic relaxation dispersion)measurements on Gd-1 revealed high longitudinal water proton relaxivity(r1=21.2 mM^(−1)s^(−1)at 60 MHz and 25℃),which originates from slow rotational motion resulting from aggregation in aqueous *** visible light irradiation,Gd-1 showed extensive photoinduced DNA cleavage in line with efficient photoinduced singlet oxygen ***-based assays revealed no significant dark cytotoxicity of Gd-1,while it showed sufficient photocytotoxicity on cancer cell lines under visible light *** results indicate the potential of this Gd(III)−porphyrin complex(Gd-1)as a core for the development of bifunctional systems acting as an efficient photodynamic therapy photosensitizer(PDt-PS)with magnetic resonance imaging(MRI)detection capabilities.

关键词： Singlet oxygen generation relaxivity Gd(III)chelate water-soluble porphyrin photocytotoxicity

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Study of the germanium dead layer influence on HP(Ge)detector efficiency by Monte Carlo simulation

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Radiation Detection technology and Methods 2018年第2期2卷 108-113页

作者： Ahmed Azbouche Mohamed Belamri théophile tchakoua Nuclear Research Center of Algiers 2 Bd Frantz FanonAlgiersAlgeria National Radiation Protection Agency of Cameroon P.O.Box 33732YaoundéCameroon

Introduction the dead layer thickness provided by the manufacturer increases with the aging of the HPGe detector;the increase of dead layer thickness leads to the decrease in the detector’s efficiency,not only due to gamma rays attenuation in the dead layer but also due to the reduction of the active volume of the *** In this work,the dead layer influence on HPGe detector efficiency was studied by Monte Carlo *** and methods the detector model was developed using Monte Carlo N Particle(MCNP5)code for adjustment of the dead layer thickness;the adjustment was performed according to a specific irradiation configuration by collimation approach using three reference point sources:^(241)Am(59.5 keV),^(137)Cs(661.6 keV)and ^(60)Co(1173.2 keV;1332.5 keV).Result the calculated efficiencies were compared to the measured intrinsic efficiency ones for these point sources;a good agreement between Monte Carlo and measurements results was found after the experimental *** the results confirm the variation in the dead layer thickness according to aging of the detector;the average change of dead layer is in order of 1.30±0.05 mm after 9 years.

关键词： HPGe detector Dead layer thickness Detector efficiency Point sources Monte Carlo simulation

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MECHANISMS INVOLVED IN thE REDUCtION OF INFARCt SIZE BY ACE INHIBItIOR AFtER LEFt CORONARY ARtERY LIGAtION IN RAtS

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Chinese Medical Journal 1995年第3期 80-81页

作者： Zhu YC Stauss HM Redlich th Adamiak D Mott A Unger th Department of Pharmacology University of Heidelberg Heidelberg GermanyDepartment of Pharmacology University of Heidelberg Heidelberg GermanyDepartment of Pharmacology University of Heidelberg Heidelberg GermanyDepartment of Pharmacology University of Heidelberg Heidelberg GermanyDepartment of Pharmacology University of Heidelberg Heidelberg GermanyDepartment of Pharmacology University of Heidelberg Heidelberg Germany

the contribution of the inhibition of angiotensin Ⅱ (ANGⅡ) synthesis and bradykinin (BK) breakdown to the effects of ACE inhibition on infarct size, cardiac hypertrophy and blood supply to the marginal zone of the i... 详细信息

关键词： ACE BK MECHANISMS INVOLVED IN thE REDUCtION OF INFARCt SIZE BY ACE INHIBItIOR AFtER LEFt CORONARY ARtERY LIGAtION IN RAtS AtI LCA

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